Science.gov

Sample records for absolute time accuracy

  1. The Impact of Strategy Instruction and Timing of Estimates on Low and High Working-Memory Capacity Readers' Absolute Monitoring Accuracy

    ERIC Educational Resources Information Center

    Linderholm, Tracy; Zhao, Qin

    2008-01-01

    Working-memory capacity, strategy instruction, and timing of estimates were investigated for their effects on absolute monitoring accuracy, which is the difference between estimated and actual reading comprehension test performance. Participants read two expository texts under one of two randomly assigned reading strategy instruction conditions…

  2. Achieving Climate Change Absolute Accuracy in Orbit

    NASA Technical Reports Server (NTRS)

    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.; Bowman, K.; Brindley, H.; Butler, J. J.; Collins, W.; Dykema, J. A.; Doelling, D. R.; Feldman, D. R.; Fox, N.; Huang, X.; Holz, R.; Huang, Y.; Jennings, D.; Jin, Z.; Johnson, D. G.; Jucks, K.; Kato, S.; Kratz, D. P.; Liu, X.; Lukashin, C.; Mannucci, A. J.; Phojanamongkolkij, N.; Roithmayr, C. M.; Sandford, S.; Taylor, P. C.; Xiong, X.

    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.

  3. Individual Differences in Absolute and Relative Metacomprehension Accuracy

    ERIC Educational Resources Information Center

    Maki, Ruth H.; Shields, Micheal; Wheeler, Amanda Easton; Zacchilli, Tammy Lowery

    2005-01-01

    The authors investigated absolute and relative metacomprehension accuracy as a function of verbal ability in college students. Students read hard texts, revised texts, or a mixed set of texts. They then predicted their performance, took a multiple-choice test on the texts, and made posttest judgments about their performance. With hard texts,…

  4. Simultaneously improving the sensitivity and absolute accuracy of CPT magnetometer.

    PubMed

    Liang, Shang-Qing; Yang, Guo-Qing; Xu, Yun-Fei; Lin, Qiang; Liu, Zhi-Heng; Chen, Zheng-Xiang

    2014-03-24

    A new method to improve the sensitivity and absolute accuracy simultaneously for coherent population trapping (CPT) magnetometer based on the differential detection method is presented. Two modulated optical beams with orthogonal circular polarizations are applied, in one of which two magnetic resonances are excited simultaneously by modulating a 3.4GHz microwave with Larmor frequency. When a microwave frequency shift is introduced, the difference in the power transmitted through the cell in each beam shows a low noise resonance. The sensitivity of 2pT/Hz @ 10Hz is achieved. Meanwhile, the absolute accuracy of ± 0.5nT within the magnetic field ranging from 20000nT to 100000nT is realized.

  5. Combined Use of Absolute and Differential Seismic Arrival Time Data to Improve Absolute Event Location

    NASA Astrophysics Data System (ADS)

    Myers, S.; Johannesson, G.

    2012-12-01

    Arrival time measurements based on waveform cross correlation are becoming more common as advanced signal processing methods are applied to seismic data archives and real-time data streams. Waveform correlation can precisely measure the time difference between the arrival of two phases, and differential time data can be used to constrain relative location of events. Absolute locations are needed for many applications, which generally requires the use of absolute time data. Current methods for measuring absolute time data are approximately two orders of magnitude less precise than differential time measurements. To exploit the strengths of both absolute and differential time data, we extend our multiple-event location method Bayesloc, which previously used absolute time data only, to include the use of differential time measurements that are based on waveform cross correlation. Fundamentally, Bayesloc is a formulation of the joint probability over all parameters comprising the multiple event location system. The Markov-Chain Monte Carlo method is used to sample from the joint probability distribution given arrival data sets. The differential time component of Bayesloc includes scaling a stochastic estimate of differential time measurement precision based the waveform correlation coefficient for each datum. For a regional-distance synthetic data set with absolute and differential time measurement error of 0.25 seconds and 0.01 second, respectively, epicenter location accuracy is improved from and average of 1.05 km when solely absolute time data are used to 0.28 km when absolute and differential time data are used jointly (73% improvement). The improvement in absolute location accuracy is the result of conditionally limiting absolute location probability regions based on the precise relative position with respect to neighboring events. Bayesloc estimates of data precision are found to be accurate for the synthetic test, with absolute and differential time measurement

  6. Constraint on Absolute Accuracy of Metacomprehension Assessments: The Anchoring and Adjustment Model vs. the Standards Model

    ERIC Educational Resources Information Center

    Kwon, Heekyung

    2011-01-01

    The objective of this study is to provide a systematic account of three typical phenomena surrounding absolute accuracy of metacomprehension assessments: (1) the absolute accuracy of predictions is typically quite low; (2) there exist individual differences in absolute accuracy of predictions as a function of reading skill; and (3) postdictions…

  7. Absolute vs. relative error characterization of electromagnetic tracking accuracy

    NASA Astrophysics Data System (ADS)

    Matinfar, Mohammad; Narayanasamy, Ganesh; Gutierrez, Luis; Chan, Raymond; Jain, Ameet

    2010-02-01

    Electromagnetic (EM) tracking systems are often used for real time navigation of medical tools in an Image Guided Therapy (IGT) system. They are specifically advantageous when the medical device requires tracking within the body of a patient where line of sight constraints prevent the use of conventional optical tracking. EM tracking systems are however very sensitive to electromagnetic field distortions. These distortions, arising from changes in the electromagnetic environment due to the presence of conductive ferromagnetic surgical tools or other medical equipment, limit the accuracy of EM tracking, in some cases potentially rendering tracking data unusable. We present a mapping method for the operating region over which EM tracking sensors are used, allowing for characterization of measurement errors, in turn providing physicians with visual feedback about measurement confidence or reliability of localization estimates. In this instance, we employ a calibration phantom to assess distortion within the operating field of the EM tracker and to display in real time the distribution of measurement errors, as well as the location and extent of the field associated with minimal spatial distortion. The accuracy is assessed relative to successive measurements. Error is computed for a reference point and consecutive measurement errors are displayed relative to the reference in order to characterize the accuracy in near-real-time. In an initial set-up phase, the phantom geometry is calibrated by registering the data from a multitude of EM sensors in a non-ferromagnetic ("clean") EM environment. The registration results in the locations of sensors with respect to each other and defines the geometry of the sensors in the phantom. In a measurement phase, the position and orientation data from all sensors are compared with the known geometry of the sensor spacing, and localization errors (displacement and orientation) are computed. Based on error thresholds provided by the

  8. Clock time is absolute and universal

    NASA Astrophysics Data System (ADS)

    Shen, Xinhang

    2015-09-01

    A critical error is found in the Special Theory of Relativity (STR): mixing up the concepts of the STR abstract time of a reference frame and the displayed time of a physical clock, which leads to use the properties of the abstract time to predict time dilation on physical clocks and all other physical processes. Actually, a clock can never directly measure the abstract time, but can only record the result of a physical process during a period of the abstract time such as the number of cycles of oscillation which is the multiplication of the abstract time and the frequency of oscillation. After Lorentz Transformation, the abstract time of a reference frame expands by a factor gamma, but the frequency of a clock decreases by the same factor gamma, and the resulting multiplication i.e. the displayed time of a moving clock remains unchanged. That is, the displayed time of any physical clock is an invariant of Lorentz Transformation. The Lorentz invariance of the displayed times of clocks can further prove within the framework of STR our earth based standard physical time is absolute, universal and independent of inertial reference frames as confirmed by both the physical fact of the universal synchronization of clocks on the GPS satellites and clocks on the earth, and the theoretical existence of the absolute and universal Galilean time in STR which has proved that time dilation and space contraction are pure illusions of STR. The existence of the absolute and universal time in STR has directly denied that the reference frame dependent abstract time of STR is the physical time, and therefore, STR is wrong and all its predictions can never happen in the physical world.

  9. Using AIRS and IASI Data to Evaluate Absolute Radiometric Accuracy and Stability for Climate Applications

    NASA Technical Reports Server (NTRS)

    Aumann, Hartmut H.; Pagano, Thomas S.

    2008-01-01

    The creation of multi-decadal data sets for climate research requires better than 100 mK absolute calibration accuracy for the full range of spectral temperatures encountered under global conditions. Validation that this accuracy is achieved by the operational hyperspectral sounders from polar orbit is facilitated by comparing data from two instruments. Extreme radiometric calibration stability is critical to allow a long time series of noisy, but presumably long-term accurate truth measurements to be used for the validation of absolute accuracy at the 100 mK level. We use the RTGSST in the tropical oceans as ground truth. The difference between the AIRS derived sst2616 and the RTGSST based on six years of data shows a systematic cold bias of about 250 mK, but better than 4 mK/year stability. The double difference between AIRS and the RTGSST and IASI and the RTGSST with less than one year of data already allows statements at the 100 mK absolute level. It shows a 60 mK difference between the AIRS and the IASI calibration at 2616 cm-(sup 1) and 300 K, with a statistically insignificant 20 mK shift in six months.

  10. High accuracy absolute laser powermeter calibrated over the whole range

    SciTech Connect

    Miron, N.; Korony, G.; Velculescu, V.G.

    1994-12-31

    The main contribution to this laser powermeter is the capability of its detector to be electrically calibrated over the whole measuring range (0 ... 100W), with an accuracy better than 1%. This allows an improved accuracy in determining the second-order polynomial coefficients describing thermocouple electric response.

  11. MSTAR: an absolute metrology sensor with sub-micron accuracy for space-based applications

    NASA Technical Reports Server (NTRS)

    Peters, Robert D.; Lay, Oliver P.; Dubovitsky, Serge; Burger, Johan P.; Jeganathan, Muthu

    2004-01-01

    The MSTAR sensor is a new system for measuring absolute distance, capable of resolving the integer cycle ambiguity of standard interferometers, and making it possible to measure distance with subnanometer accuracy.

  12. Confidence-Accuracy Calibration in Absolute and Relative Face Recognition Judgments

    ERIC Educational Resources Information Center

    Weber, Nathan; Brewer, Neil

    2004-01-01

    Confidence-accuracy (CA) calibration was examined for absolute and relative face recognition judgments as well as for recognition judgments from groups of stimuli presented simultaneously or sequentially (i.e., simultaneous or sequential mini-lineups). When the effect of difficulty was controlled, absolute and relative judgments produced…

  13. Accuracy of the Residual Delay Absolute Phase Algorithm

    NASA Technical Reports Server (NTRS)

    Imel, D. A.

    1996-01-01

    Interferometric synthetic aperture radar (IFSAR) has become a useful technology for producing high-quality topographic maps. These measurements are required to reconstruct the three-dimensional coordinate of a point in an IFSAR image: the range, azimuth and elevation. The first is obtained by timing the return of the radar pulse, the second by measuring the doppler shift, and the last by measuring the phase difference between the signals received at two displaced antennae.

  14. High accuracy time transfer synchronization

    NASA Technical Reports Server (NTRS)

    Wheeler, Paul J.; Koppang, Paul A.; Chalmers, David; Davis, Angela; Kubik, Anthony; Powell, William M.

    1995-01-01

    In July 1994, the U.S. Naval Observatory (USNO) Time Service System Engineering Division conducted a field test to establish a baseline accuracy for two-way satellite time transfer synchronization. Three Hewlett-Packard model 5071 high performance cesium frequency standards were transported from the USNO in Washington, DC to Los Angeles, California in the USNO's mobile earth station. Two-Way Satellite Time Transfer links between the mobile earth station and the USNO were conducted each day of the trip, using the Naval Research Laboratory(NRL) designed spread spectrum modem, built by Allen Osborne Associates(AOA). A Motorola six channel GPS receiver was used to track the location and altitude of the mobile earth station and to provide coordinates for calculating Sagnac corrections for the two-way measurements, and relativistic corrections for the cesium clocks. This paper will discuss the trip, the measurement systems used and the results from the data collected. We will show the accuracy of using two-way satellite time transfer for synchronization and the performance of the three HP 5071 cesium clocks in an operational environment.

  15. High accuracy time transfer synchronization

    NASA Astrophysics Data System (ADS)

    Wheeler, Paul J.; Koppang, Paul A.; Chalmers, David; Davis, Angela; Kubik, Anthony; Powell, William M.

    1995-05-01

    In July 1994, the U.S. Naval Observatory (USNO) Time Service System Engineering Division conducted a field test to establish a baseline accuracy for two-way satellite time transfer synchronization. Three Hewlett-Packard model 5071 high performance cesium frequency standards were transported from the USNO in Washington, DC to Los Angeles, California in the USNO's mobile earth station. Two-Way Satellite Time Transfer links between the mobile earth station and the USNO were conducted each day of the trip, using the Naval Research Laboratory(NRL) designed spread spectrum modem, built by Allen Osborne Associates(AOA). A Motorola six channel GPS receiver was used to track the location and altitude of the mobile earth station and to provide coordinates for calculating Sagnac corrections for the two-way measurements, and relativistic corrections for the cesium clocks. This paper will discuss the trip, the measurement systems used and the results from the data collected. We will show the accuracy of using two-way satellite time transfer for synchronization and the performance of the three HP 5071 cesium clocks in an operational environment.

  16. Absolute calibration accuracy of L4 TM and L5 TM sensor image pairs

    USGS Publications Warehouse

    Chander, G.; Micijevic, E.

    2006-01-01

    The Landsat suite of satellites has collected the longest continuous archive of multispectral data of any land-observing space program. From the Landsat program's inception in 1972 to the present, the Earth science user community has benefited from a historical record of remotely sensed data. However, little attention has been paid to ensuring that the data are calibrated and comparable from mission to mission, Launched in 1982 and 1984 respectively, the Landsat 4 (L4) and Landsat 5 (L5) Thematic Mappers (TM) are the backbone of an extensive archive of moderate resolution Earth imagery. To evaluate the "current" absolute accuracy of these two sensors, image pairs from the L5 TM and L4 TM sensors were compared. The approach involves comparing image statistics derived from large common areas observed eight days apart by the two sensors. The average percent differences in reflectance estimates obtained from the L4 TM agree with those from the L5 TM to within 15 percent. Additional work to characterize the absolute differences between the two sensors over the entire mission is in progress.

  17. Henry More and the development of absolute time.

    PubMed

    Thomas, Emily

    2015-12-01

    This paper explores the nature, development and influence of the first English account of absolute time, put forward in the mid-seventeenth century by the 'Cambridge Platonist' Henry More. Against claims in the literature that More does not have an account of time, this paper sets out More's evolving account and shows that it reveals the lasting influence of Plotinus. Further, this paper argues that More developed his views on time in response to his adoption of Descartes' vortex cosmology and cosmogony, providing new evidence of More's wider project to absorb Cartesian natural philosophy into his Platonic metaphysics. Finally, this paper argues that More should be added to the list of sources that later English thinkers - including Newton and Samuel Clarke - drew on in constructing their absolute accounts of time. PMID:26568082

  18. Absolute Binding Free Energy Calculations: On the Accuracy of Computational Scoring of Protein-ligand Interactions

    PubMed Central

    Singh, Nidhi; Warshel, Arieh

    2010-01-01

    Calculating the absolute binding free energies is a challenging task. Reliable estimates of binding free energies should provide a guide for rational drug design. It should also provide us with deeper understanding of the correlation between protein structure and its function. Further applications may include identifying novel molecular scaffolds and optimizing lead compounds in computer-aided drug design. Available options to evaluate the absolute binding free energies range from the rigorous but expensive free energy perturbation to the microscopic Linear Response Approximation (LRA/β version) and its variants including the Linear Interaction Energy (LIE) to the more approximated and considerably faster scaled Protein Dipoles Langevin Dipoles (PDLD/S-LRA version), as well as the less rigorous Molecular Mechanics Poisson–Boltzmann/Surface Area (MM/PBSA) and Generalized Born/Surface Area (MM/GBSA) to the less accurate scoring functions. There is a need for an assessment of the performance of different approaches in terms of computer time and reliability. We present a comparative study of the LRA/β, the LIE, the PDLD/S-LRA/β and the more widely used MM/PBSA and assess their abilities to estimate the absolute binding energies. The LRA and LIE methods perform reasonably well but require specialized parameterization for the non-electrostatic term. On the average, the PDLD/S-LRA/β performs effectively. Our assessment of the MM/PBSA is less optimistic. This approach appears to provide erroneous estimates of the absolute binding energies due to its incorrect entropies and the problematic treatment of electrostatic energies. Overall, the PDLD/S-LRA/β appears to offer an appealing option for the final stages of massive screening approaches. PMID:20186976

  19. Handheld Reflective Foil Emissometer with 0.007 Absolute Accuracy at 0.05

    NASA Astrophysics Data System (ADS)

    van der Ham, E. W. M.; Ballico, M. J.

    2014-07-01

    The development and performance of a handheld emissometer for the measurement of the emissivity of highly reflective metallic foils used for the insulation of domestic and commercial buildings are described. Reflective roofing insulation based on a thin coating of metal on a more robust substrate is very widely used in hotter climates to reduce the radiant heat transfer between the ceiling and roof in commercial and residential buildings. The required normal emissivity of these foils is generally below 0.05, so stray reflected ambient infrared radiation (IR) makes traditional reflectance-based measurements of emissivity very difficult to achieve with the required accuracy. Many manufacturers apply additional coatings onto the metallic foil to reduce visible glare during installation on a roof, and to provide protection to the thin reflective layer; however, this layer can also substantially increase the IR emissivity. The system as developed at the National Measurement Institute, Australia (NMIA) is based on the principle of measurement of the modulation in thermal infrared radiation, as the sample is thermally modulated by hot and cold air streams. A commercial infrared to band radiation thermometer with a highly specialized stray and reflected radiation shroud attachment is used as the detector system, allowing for convenient handheld field measurements. The performance and accuracy of the system have been compared with NMIA's reference emissometer systems for a number of typical material samples, demonstrating its capability to measure the absolute thermal emissivity of these very highly reflective foils with an uncertainty of better than.

  20. Precision and accuracy in the quantitative analysis of biological samples by accelerator mass spectrometry: application in microdose absolute bioavailability studies.

    PubMed

    Gao, Lan; Li, Jing; Kasserra, Claudia; Song, Qi; Arjomand, Ali; Hesk, David; Chowdhury, Swapan K

    2011-07-15

    Determination of the pharmacokinetics and absolute bioavailability of an experimental compound, SCH 900518, following a 89.7 nCi (100 μg) intravenous (iv) dose of (14)C-SCH 900518 2 h post 200 mg oral administration of nonradiolabeled SCH 900518 to six healthy male subjects has been described. The plasma concentration of SCH 900518 was measured using a validated LC-MS/MS system, and accelerator mass spectrometry (AMS) was used for quantitative plasma (14)C-SCH 900518 concentration determination. Calibration standards and quality controls were included for every batch of sample analysis by AMS to ensure acceptable quality of the assay. Plasma (14)C-SCH 900518 concentrations were derived from the regression function established from the calibration standards, rather than directly from isotopic ratios from AMS measurement. The precision and accuracy of quality controls and calibration standards met the requirements of bioanalytical guidance (U.S. Department of Health and Human Services, Food and Drug Administration, Center for Drug Evaluation and Research, Center for Veterinary Medicine. Guidance for Industry: Bioanalytical Method Validation (ucm070107), May 2001. http://www.fda.gov/downloads/Drugs/GuidanceCompilanceRegulatoryInformation/Guidances/ucm070107.pdf ). The AMS measurement had a linear response range from 0.0159 to 9.07 dpm/mL for plasma (14)C-SCH 900158 concentrations. The CV and accuracy were 3.4-8.5% and 94-108% (82-119% for the lower limit of quantitation (LLOQ)), respectively, with a correlation coefficient of 0.9998. The absolute bioavailability was calculated from the dose-normalized area under the curve of iv and oral doses after the plasma concentrations were plotted vs the sampling time post oral dose. The mean absolute bioavailability of SCH 900518 was 40.8% (range 16.8-60.6%). The typical accuracy and standard deviation in AMS quantitative analysis of drugs from human plasma samples have been reported for the first time, and the impact of these

  1. Accuracy metrics for judging time scale algorithms

    NASA Technical Reports Server (NTRS)

    Douglas, R. J.; Boulanger, J.-S.; Jacques, C.

    1994-01-01

    Time scales have been constructed in different ways to meet the many demands placed upon them for time accuracy, frequency accuracy, long-term stability, and robustness. Usually, no single time scale is optimum for all purposes. In the context of the impending availability of high-accuracy intermittently-operated cesium fountains, we reconsider the question of evaluating the accuracy of time scales which use an algorithm to span interruptions of the primary standard. We consider a broad class of calibration algorithms that can be evaluated and compared quantitatively for their accuracy in the presence of frequency drift and a full noise model (a mixture of white PM, flicker PM, white FM, flicker FM, and random walk FM noise). We present the analytic techniques for computing the standard uncertainty for the full noise model and this class of calibration algorithms. The simplest algorithm is evaluated to find the average-frequency uncertainty arising from the noise of the cesium fountain's local oscillator and from the noise of a hydrogen maser transfer-standard. This algorithm and known noise sources are shown to permit interlaboratory frequency transfer with a standard uncertainty of less than 10(exp -15) for periods of 30-100 days.

  2. Inertial Measures of Motion for Clinical Biomechanics: Comparative Assessment of Accuracy under Controlled Conditions – Changes in Accuracy over Time

    PubMed Central

    Lebel, Karina; Boissy, Patrick; Hamel, Mathieu; Duval, Christian

    2015-01-01

    Background Interest in 3D inertial motion tracking devices (AHRS) has been growing rapidly among the biomechanical community. Although the convenience of such tracking devices seems to open a whole new world of possibilities for evaluation in clinical biomechanics, its limitations haven’t been extensively documented. The objectives of this study are: 1) to assess the change in absolute and relative accuracy of multiple units of 3 commercially available AHRS over time; and 2) to identify different sources of errors affecting AHRS accuracy and to document how they may affect the measurements over time. Methods This study used an instrumented Gimbal table on which AHRS modules were carefully attached and put through a series of velocity-controlled sustained motions including 2 minutes motion trials (2MT) and 12 minutes multiple dynamic phases motion trials (12MDP). Absolute accuracy was assessed by comparison of the AHRS orientation measurements to those of an optical gold standard. Relative accuracy was evaluated using the variation in relative orientation between modules during the trials. Findings Both absolute and relative accuracy decreased over time during 2MT. 12MDP trials showed a significant decrease in accuracy over multiple phases, but accuracy could be enhanced significantly by resetting the reference point and/or compensating for initial Inertial frame estimation reference for each phase. Interpretation The variation in AHRS accuracy observed between the different systems and with time can be attributed in part to the dynamic estimation error, but also and foremost, to the ability of AHRS units to locate the same Inertial frame. Conclusions Mean accuracies obtained under the Gimbal table sustained conditions of motion suggest that AHRS are promising tools for clinical mobility assessment under constrained conditions of use. However, improvement in magnetic compensation and alignment between AHRS modules are desirable in order for AHRS to reach their

  3. Absolute thickness metrology with submicrometer accuracy using a low-coherence distance measuring interferometer.

    PubMed

    Zhao, Yang; Schmidt, Greg; Moore, Duncan T; Ellis, Jonathan D

    2015-09-01

    Absolute physical thickness across the sample aperture is critical in determining the index of a refraction profile from the optical path length profile for gradient index (GRIN) materials, which have a designed inhomogeneous refractive index. Motivated by this application, instrumentation was established to measure the absolute thickness of samples with nominally plane-parallel surfaces up to 50 mm thick. The current system is capable of measuring absolute thickness with 120 nm (1σ) repeatability and submicrometer expanded measurement uncertainty. Beside GRIN materials, this method is also capable of measuring other inhomogeneous and opaque materials. PMID:26368894

  4. Absolute Timing of the Crab Pulsar with RXTE

    NASA Technical Reports Server (NTRS)

    Rots, Arnold H.; Jahoda, Keith; Lyne, Andrew G.

    2004-01-01

    We have monitored the phase of the main X-ray pulse of the Crab pulsar with the Rossi X-ray Timing Explorer (RXTE) for almost eight years, since the start of the mission in January 1996. The absolute time of RXTE's clock is sufficiently accurate to allow this phase to be compared directly with the radio profile. Our monitoring observations of the pulsar took place bi-weekly (during the periods when it was at least 30 degrees from the Sun) and we correlated the data with radio timing ephemerides derived from observations made at Jodrell Bank. We have determined the phase of the X-ray main pulse for each observation with a typical error in the individual data points of 50 microseconds. The total ensemble is consistent with a phase that is constant over the monitoring period, with the X-ray pulse leading the radio pulse by 0.01025 plus or minus 0.00120 period in phase, or 344 plus or minus 40 microseconds in time. The error estimate is dominated by a systematic error of 40 microseconds, most likely constant, arising from uncertainties in the instrumental calibration of the radio data. The statistical error is 0.00015 period, or 5 microseconds. The separation of the main pulse and interpulse appears to be unchanging at time scales of a year or less, with an average value of 0.4001 plus or minus 0.0002 period. There is no apparent variation in these values with energy over the 2-30 keV range. The lag between the radio and X-ray pulses ma be constant in phase (i.e., rotational in nature) or constant in time (i.e., due to a pathlength difference). We are not (yet) able to distinguish between these two interpretations.

  5. Time-resolved Absolute Velocity Quantification with Projections

    PubMed Central

    Langham, Michael C.; Jain, Varsha; Magland, Jeremy F.; Wehrli, Felix W.

    2010-01-01

    Quantitative information on time-resolved blood velocity along the femoral/popliteal artery can provide clinical information on peripheral arterial disease and complement MR angiography since not all stenoses are hemodynamically significant. The key disadvantages of the most widely used approach to time-resolve pulsatile blood flow by cardiac-gated velocity-encoded gradient-echo imaging are gating errors and long acquisition time. Here we demonstrate a rapid non-triggered method that quantifies absolute velocity on the basis of phase difference between successive velocity-encoded projections after selectively removing the background static tissue signal via a reference image. The tissue signal from the reference image’s center k-space line is isolated by masking out the vessels in the image domain. The performance of the technique, in terms of reproducibility and agreement with results obtained with conventional phase contrast (PC)-MRI was evaluated at 3T field strength with a variable-flow rate phantom and in vivo of the triphasic velocity waveforms at several segments along the femoral and popliteal arteries. Additionally, time-resolved flow velocity was quantified in five healthy subjects and compared against gated PC-MRI results. To illustrate clinical feasibility the proposed method was shown to be able to identify hemodynamic abnormalities and impaired reactivity in a diseased femoral artery. For both phantom and in vivo studies, velocity measurements were within 1.5 cm/s and the coefficient of variation was less than 5% in an in vivo reproducibility study. In five healthy subjects, the average differences in mean peak velocities and their temporal locations were within 1 cm/s and 10 ms compared to gated PC-MRI. In conclusion, the proposed method provides temporally-resolved arterial velocity with a temporal resolution of 20 ms with minimal post-processing. PMID:20677235

  6. Multi-channel data acquisition system with absolute time synchronization

    NASA Astrophysics Data System (ADS)

    Włodarczyk, Przemysław; Pustelny, Szymon; Budker, Dmitry; Lipiński, Marcin

    2014-11-01

    We present a low-cost, stand-alone global-time-synchronized data acquisition system. Our prototype allows recording up to four analog signals with a 16-bit resolution in variable ranges and a maximum sampling rate of 1000 S/s. The system simultaneously acquires readouts of external sensors e.g. magnetometer or thermometer. A complete data set, including a header containing timestamp, is stored on a Secure Digital (SD) card or transmitted to a computer using Universal Serial Bus (USB). The estimated time accuracy of the data acquisition is better than ±200 ns. The device is intended for use in a global network of optical magnetometers (the Global Network of Optical Magnetometers for Exotic physics - GNOME), which aims to search for signals heralding physics beyond the Standard Model, that can be generated by ordinary spin coupling to exotic particles or anomalous spin interactions.

  7. Improved Strategies and Optimization of Calibration Models for Real-time PCR Absolute Quantification

    EPA Science Inventory

    Real-time PCR absolute quantification applications rely on the use of standard curves to make estimates of DNA target concentrations in unknown samples. Traditional absolute quantification approaches dictate that a standard curve must accompany each experimental run. However, t...

  8. Time and position accuracy using codeless GPS

    NASA Technical Reports Server (NTRS)

    Dunn, C. E.; Jefferson, D. C.; Lichten, S. M.; Thomas, J. B.; Vigue, Y.; Young, L. E.

    1994-01-01

    The Global Positioning System has allowed scientists and engineers to make measurements having accuracy far beyond the original 15 meter goal of the system. Using global networks of P-Code capable receivers and extensive post-processing, geodesists have achieved baseline precision of a few parts per billion, and clock offsets have been measured at the nanosecond level over intercontinental distances. A cloud hangs over this picture, however. The Department of Defense plans to encrypt the P-Code (called Anti-Spoofing, or AS) in the fall of 1993. After this event, geodetic and time measurements will have to be made using codeless GPS receivers. However, there appears to be a silver lining to the cloud. In response to the anticipated encryption of the P-Code, the geodetic and GPS receiver community has developed some remarkably effective means of coping with AS without classified information. We will discuss various codeless techniques currently available and the data noise resulting from each. We will review some geodetic results obtained using only codeless data, and discuss the implications for time measurements. Finally, we will present the status of GPS research at JPL in relation to codeless clock measurements.

  9. Approximating relational observables by absolute quantities: a quantum accuracy-size trade-off

    NASA Astrophysics Data System (ADS)

    Miyadera, Takayuki; Loveridge, Leon; Busch, Paul

    2016-05-01

    The notion that any physical quantity is defined and measured relative to a reference frame is traditionally not explicitly reflected in the theoretical description of physical experiments where, instead, the relevant observables are typically represented as ‘absolute’ quantities. However, the emergence of the resource theory of quantum reference frames as a new branch of quantum information science in recent years has highlighted the need to identify the physical conditions under which a quantum system can serve as a good reference. Here we investigate the conditions under which, in quantum theory, an account in terms of absolute quantities can provide a good approximation of relative quantities. We find that this requires the reference system to be large in a suitable sense.

  10. Absolute GPS Time Event Generation and Capture for Remote Locations

    NASA Astrophysics Data System (ADS)

    HIRES Collaboration

    The HiRes experiment operates fixed location and portable lasers at remote desert locations to generate calibration events. One physics goal of HiRes is to search for unusual showers. These may appear similar to upward or horizontally pointing laser tracks used for atmospheric calibration. It is therefore necessary to remove all of these calibration events from the HiRes detector data stream in a physics blind manner. A robust and convenient "tagging" method is to generate the calibration events at precisely known times. To facilitate this tagging method we have developed the GPSY (Global Positioning System YAG) module. It uses a GPS receiver, an embedded processor and additional timing logic to generate laser triggers at arbitrary programmed times and frequencies with better than 100nS accuracy. The GPSY module has two trigger outputs (one microsecond resolution) to trigger the laser flash-lamp and Q-switch and one event capture input (25nS resolution). The GPSY module can be programmed either by a front panel menu based interface or by a host computer via an RS232 serial interface. The latter also allows for computer logging of generated and captured event times. Details of the design and the implementation of these devices will be presented. 1 Motivation Air Showers represent a small fraction, much less than a percent, of the total High Resolution Fly's Eye data sample. The bulk of the sample is calibration data. Most of this calibration data is generated by two types of systems that use lasers. One type sends light directly to the detectors via optical fibers to monitor detector gains (Girard 2001). The other sends a beam of light into the sky and the scattered light that reaches the detectors is used to monitor atmospheric effects (Wiencke 1998). It is important that these calibration events be cleanly separated from the rest of the sample both to provide a complete set of monitoring information, and more

  11. Absolute accuracy of the Cyberware WB4 whole-body scanner

    NASA Astrophysics Data System (ADS)

    Daanen, Hein A. M.; Taylor, Stacie E.; Brunsman, Matthew A.; Nurre, Joseph H.

    1997-03-01

    The Cyberware WB4 whole body scanner is one of the first scanning systems in the world that generates a high resolution data set of the outer surface of the human body. The Computerized Anthropometric Research and Design (CARD) Laboratory of Wright-Patterson AFB intends to use the scanner to enable quick and reliable acquisition of anthropometric data. For this purpose, a validation study was initiated to check the accuracy, reliability and errors of the system. A calibration object, consisting of two boxes and a cylinder, was scanned in several locations in the scanning space. The object dimensions in the resulting scans compared favorably to the actual dimensions of the calibration object.

  12. Correction to Method of Establishing the Absolute Radiometric Accuracy of Remote Sensing Systems While On-orbit Using Characterized Stellar Sources

    NASA Technical Reports Server (NTRS)

    Bowen, Howard S.; Cunningham, Douglas M.

    2007-01-01

    The contents include: 1) Brief history of related events; 2) Overview of original method used to establish absolute radiometric accuracy of remote sensing instruments using stellar sources; and 3) Considerations to improve the stellar calibration approach.

  13. Time-series modeling and prediction of global monthly absolute temperature for environmental decision making

    NASA Astrophysics Data System (ADS)

    Ye, Liming; Yang, Guixia; Van Ranst, Eric; Tang, Huajun

    2013-03-01

    A generalized, structural, time series modeling framework was developed to analyze the monthly records of absolute surface temperature, one of the most important environmental parameters, using a deterministicstochastic combined (DSC) approach. Although the development of the framework was based on the characterization of the variation patterns of a global dataset, the methodology could be applied to any monthly absolute temperature record. Deterministic processes were used to characterize the variation patterns of the global trend and the cyclic oscillations of the temperature signal, involving polynomial functions and the Fourier method, respectively, while stochastic processes were employed to account for any remaining patterns in the temperature signal, involving seasonal autoregressive integrated moving average (SARIMA) models. A prediction of the monthly global surface temperature during the second decade of the 21st century using the DSC model shows that the global temperature will likely continue to rise at twice the average rate of the past 150 years. The evaluation of prediction accuracy shows that DSC models perform systematically well against selected models of other authors, suggesting that DSC models, when coupled with other ecoenvironmental models, can be used as a supplemental tool for short-term (˜10-year) environmental planning and decision making.

  14. Time dependent corrections to absolute gravity determinations in the establishment of modern gravity control

    NASA Astrophysics Data System (ADS)

    Dykowski, Przemyslaw; Krynski, Jan

    2015-04-01

    The establishment of modern gravity control with the use of exclusively absolute method of gravity determination has significant advantages as compared to the one established mostly with relative gravity measurements (e.g. accuracy, time efficiency). The newly modernized gravity control in Poland consists of 28 fundamental stations (laboratory) and 168 base stations (PBOG14 - located in the field). Gravity at the fundamental stations was surveyed with the FG5-230 gravimeter of the Warsaw University of Technology, and at the base stations - with the A10-020 gravimeter of the Institute of Geodesy and Cartography, Warsaw. This work concerns absolute gravity determinations at the base stations. Although free of common relative measurement errors (e.g. instrumental drift) and effects of network adjustment, absolute gravity determinations for the establishment of gravity control require advanced corrections due to time dependent factors, i.e. tidal and ocean loading corrections, atmospheric corrections and hydrological corrections that were not taken into account when establishing the previous gravity control in Poland. Currently available services and software allow to determine high accuracy and high temporal resolution corrections for atmospheric (based on digital weather models, e.g. ECMWF) and hydrological (based on hydrological models, e.g. GLDAS/Noah) gravitational and loading effects. These corrections are mostly used for processing observations with Superconducting Gravimeters in the Global Geodynamics Project. For the area of Poland the atmospheric correction based on weather models can differ from standard atmospheric correction by even ±2 µGal. The hydrological model shows the annual variability of ±8 µGal. In addition the standard tidal correction may differ from the one obtained from the local tidal model (based on tidal observations). Such difference at Borowa Gora Observatory reaches the level of ±1.5 µGal. Overall the sum of atmospheric and

  15. SU-E-T-189: First Experimental Verification of the Accuracy of Absolute Dose Reconstruction From PET-CT Imaging of Yttrium 90 Microspheres

    SciTech Connect

    Veltchev, I; Fourkal, E; Doss, M; Ma, C; Meyer, J; Yu, M; Horwitz, E

    2014-06-01

    Purpose: In the past few years there have been numerous proposals for 3D dose reconstruction from the PET-CT imaging of patients undergoing radioembolization treatment of the liver with yttrium-90 microspheres. One of the most promising techniques uses convolution of the measured PET activity distribution with a pre-calculated Monte Carlo dose deposition kernel. The goal of the present study is to experimentally verify the accuracy of this method and to analyze the significance of various error sources. Methods: Optically stimulated luminescence detectors (OSLD) were used (NanoDot, Landauer) in this experiment. Two detectors were mounted on the central axis of a cylinder filled with water solution of yttrium-90 chloride. The total initial activity was 90mCi. The cylinder was inserted in a larger water phantom and scanned on a Siemens Biograph 16 Truepoint PET-CT scanner. Scans were performed daily over a period of 20 days to build a calibration curve for the measured absolute activity spanning 7 yttrium-90 half-lives. The OSLDs were mounted in the phantom for a predetermined period of time in order to record 2Gy dose. The measured dose was then compared to the dose reconstructed from the activity density at the location of each dosimeter. Results: Thorough error analysis of the dose reconstruction algorithm takes into account the uncertainties in the absolute PET activity, branching ratios, and nonlinearity of the calibration curve. The measured dose for 105-minute exposure on day 10 of the experiment was 219(11)cGy, while the reconstructed dose at the location of the detector was 215(47)cGy. Conclusion: We present the first experimental verification of the accuracy of the convolution algorithm for absolute dose reconstruction of yttrium-90 microspheres. The excellent agreement between the measured and calculated point doses will encourage the broad clinical adoption of the convolution-based dose reconstruction algorithm, making future quantitative dose

  16. Improvement in absolute calibration accuracy of Landsat-5 TM with Landsat-7 ETM+ data

    NASA Astrophysics Data System (ADS)

    Chander, Gyanesh; Markham, Brian L.; Micijevic, Esad; Teillet, Philippe M.; Helder, Dennis L.

    2005-08-01

    The ability to detect and quantify changes in the Earth's environment depends on satellites sensors that can provide calibrated, consistent measurements of Earth's surface features through time. A critical step in this process is to put image data from subsequent generations of sensors onto a common radiometric scale. To evaluate Landsat-5 (L5) Thematic Mapper's (TM) utility in this role, image pairs from the L5 TM and Landsat-7 (L7) Enhanced Thematic Mapper Plus (ETM+) sensors were compared. This approach involves comparison of surface observations based on image statistics from large common areas observed eight days apart by the two sensors. The results indicate a significant improvement in the consistency of L5 TM data with respect to L7 ETM+ data, achieved using a revised Look-Up-Table (LUT) procedure as opposed to the historical Internal Calibrator (IC) procedure previously used in the L5 TM product generation system. The average percent difference in reflectance estimates obtained from the L5 TM agree with those from the L7 ETM+ in the Visible and Near Infrared (VNIR) bands to within four percent and in the Short Wave Infrared (SWIR) bands to within six percent.

  17. Improvement in absolute calibration accuracy of Landsat-5 TM with Landsat-7 ETM+ data

    USGS Publications Warehouse

    Chander, G.; Markham, B.L.; Micijevic, E.; Teillet, P.M.; Helder, D.L.; ,

    2005-01-01

    The ability to detect and quantify changes in the Earth's environment depends on satellites sensors that can provide calibrated, consistent measurements of Earth's surface features through time. A critical step in this process is to put image data from subsequent generations of sensors onto a common radiometric scale. To evaluate Landsat-5 (L5) Thematic Mapper's (TM) utility in this role, image pairs from the L5 TM and Landsat-7 (L7) Enhanced Thematic Mapper Plus (ETM+) sensors were compared. This approach involves comparison of surface observations based on image statistics from large common areas observed eight days apart by the two sensors. The results indicate a significant improvement in the consistency of L5 TM data with respect to L7 ETM+ data, achieved using a revised Look-Up-Table (LUT) procedure as opposed to the historical Internal Calibrator (IC) procedure previously used in the L5 TM product generation system. The average percent difference in reflectance estimates obtained from the L5 TM agree with those from the L7 ETM+ in the Visible and Near Infrared (VNIR) bands to within four percent and in the Short Wave Infrared (SWIR) bands to within six percent.

  18. Speed-Accuracy Response Models: Scoring Rules Based on Response Time and Accuracy

    ERIC Educational Resources Information Center

    Maris, Gunter; van der Maas, Han

    2012-01-01

    Starting from an explicit scoring rule for time limit tasks incorporating both response time and accuracy, and a definite trade-off between speed and accuracy, a response model is derived. Since the scoring rule is interpreted as a sufficient statistic, the model belongs to the exponential family. The various marginal and conditional distributions…

  19. Modeling Individual Differences in Response Time and Accuracy in Numeracy

    PubMed Central

    Ratcliff, Roger; Thompson, Clarissa A.; McKoon, Gail

    2015-01-01

    In the study of numeracy, some hypotheses have been based on response time (RT) as a dependent variable and some on accuracy, and considerable controversy has arisen about the presence or absence of correlations between RT and accuracy, between RT or accuracy and individual differences like IQ and math ability, and between various numeracy tasks. In this article, we show that an integration of the two dependent variables is required, which we accomplish with a theory-based model of decision making. We report data from four tasks: numerosity discrimination, number discrimination, memory for two-digit numbers, and memory for three-digit numbers. Accuracy correlated across tasks, as did RTs. However, the negative correlations that might be expected between RT and accuracy were not obtained; if a subject was accurate, it did not mean that they were fast (and vice versa). When the diffusion decision-making model was applied to the data (Ratcliff, 1978), we found significant correlations across the tasks between the quality of the numeracy information (drift rate) driving the decision process and between the speed/ accuracy criterion settings, suggesting that similar numeracy skills and similar speed-accuracy settings are involved in the four tasks. In the model, accuracy is related to drift rate and RT is related to speed-accuracy criteria, but drift rate and criteria are not related to each other across subjects. This provides a theoretical basis for understanding why negative correlations were not obtained between accuracy and RT. We also manipulated criteria by instructing subjects to maximize either speed or accuracy, but still found correlations between the criteria settings between and within tasks, suggesting that the settings may represent an individual trait that can be modulated but not equated across subjects. Our results demonstrate that a decision-making model may provide a way to reconcile inconsistent and sometimes contradictory results in numeracy

  20. COMPASS time synchronization and dissemination—Toward centimetre positioning accuracy

    NASA Astrophysics Data System (ADS)

    Wang, ZhengBo; Zhao, Lu; Wang, ShiGuang; Zhang, JianWei; Wang, Bo; Wang, LiJun

    2014-09-01

    In this paper we investigate methods to achieve highly accurate time synchronization among the satellites of the COMPASS global navigation satellite system (GNSS). Owing to the special design of COMPASS which implements several geo-stationary satellites (GEO), time synchronization can be highly accurate via microwave links between ground stations to the GEO satellites. Serving as space-borne relay stations, the GEO satellites can further disseminate time and frequency signals to other satellites such as the inclined geo-synchronous (IGSO) and mid-earth orbit (MEO) satellites within the system. It is shown that, because of the accuracy in clock synchronization, the theoretical accuracy of COMPASS positioning and navigation will surpass that of the GPS. In addition, the COMPASS system can function with its entire positioning, navigation, and time-dissemination services even without the ground link, thus making it much more robust and secure. We further show that time dissemination using the COMPASS-GEO satellites to earth-fixed stations can achieve very high accuracy, to reach 100 ps in time dissemination and 3 cm in positioning accuracy, respectively. In this paper, we also analyze two feasible synchronization plans. All special and general relativistic effects related to COMPASS clocks frequency and time shifts are given. We conclude that COMPASS can reach centimeter-level positioning accuracy and discuss potential applications.

  1. Distinguishing Fast and Slow Processes in Accuracy - Response Time Data.

    PubMed

    Coomans, Frederik; Hofman, Abe; Brinkhuis, Matthieu; van der Maas, Han L J; Maris, Gunter

    2016-01-01

    We investigate the relation between speed and accuracy within problem solving in its simplest non-trivial form. We consider tests with only two items and code the item responses in two binary variables: one indicating the response accuracy, and one indicating the response speed. Despite being a very basic setup, it enables us to study item pairs stemming from a broad range of domains such as basic arithmetic, first language learning, intelligence-related problems, and chess, with large numbers of observations for every pair of problems under consideration. We carry out a survey over a large number of such item pairs and compare three types of psychometric accuracy-response time models present in the literature: two 'one-process' models, the first of which models accuracy and response time as conditionally independent and the second of which models accuracy and response time as conditionally dependent, and a 'two-process' model which models accuracy contingent on response time. We find that the data clearly violates the restrictions imposed by both one-process models and requires additional complexity which is parsimoniously provided by the two-process model. We supplement our survey with an analysis of the erroneous responses for an example item pair and demonstrate that there are very significant differences between the types of errors in fast and slow responses. PMID:27167518

  2. The movement speed-accuracy relation in space-time.

    PubMed

    Hsieh, Tsung-Yu; Liu, Yeou-Teh; Mayer-Kress, Gottfried; Newell, Karl M

    2013-02-01

    Two experiments investigated a new approach to decomposing the contributions of spatial and temporal constraints to an integrated single space-time performance score in the movement speed-accuracy relation of a line drawing task. The mean and variability of the space-time performance error score were lowest when the task space and time constraint contributions to the performance score were comparable (i.e., middle range of velocities). As the contribution of either space or time to the performance score became increasingly asymmetrical at lower and higher average velocities, the mean performance error score and its variability increased with a greater trade-off between spatial and temporal movement properties. The findings revealed a new U-shaped space-time speed-accuracy function for performance outcome in tasks that have both spatial and temporal demands. The traditional speed-accuracy functions for spatial error and temporal error considered independently map to this integrated space-time movement speed-accuracy function.

  3. Accuracy of Pedometer Steps and Time for Youth with Disabilities

    ERIC Educational Resources Information Center

    Beets, Michael W.; Combs, Cindy; Pitetti, Kenneth H.; Morgan, Melinda; Bryan, Rebecca R.; Foley, John T.

    2007-01-01

    The purpose of the study was to examine the accuracy of pedometer steps and activity time (Walk4Life, WL) for youth with developmental disabilities. Eighteen youth (11 girls, 7 boys) 4-14 years completed six 80-meter self-paced walking trials while wearing a pedometer at five waist locations (front right, front left, back right, back left, middle…

  4. An evaluation of the accuracy of geomagnetic data obtained from an unattended, automated, quasi-absolute station

    USGS Publications Warehouse

    Herzog, D.C.

    1990-01-01

    A comparison is made of geomagnetic calibration data obtained from a high-sensitivity proton magnetometer enclosed within an orthogonal bias coil system, with data obtained from standard procedures at a mid-latitude U.S. Geological Survey magnetic observatory using a quartz horizontal magnetometer, a Ruska magnetometer, and a total field magnetometer. The orthogonal coil arrangement is used with the proton magnetometer to provide Deflected-Inclination-Deflected-Declination (DIDD) data from which quasi-absolute values of declination, horizontal intensity, and vertical intensity can be derived. Vector magnetometers provide the ordinate values to yield baseline calibrations for both the DIDD and standard observatory processes. Results obtained from a prototype system over a period of several months indicate that the DIDD unit can furnish adequate absolute field values for maintaining observatory calibration data, thus providing baseline control for unattended, remote stations. ?? 1990.

  5. Timing of spacecraft date: Time accuracy requirements and timing facilities of the European Space Agency (ESA)

    NASA Astrophysics Data System (ADS)

    Dworak, H. P.

    1985-04-01

    The time accuracy requirements for various European Space Agency (ESA) missions are analyzed; the requirements are grouped by the type of mission. The evolution of satellite timing techniques since 1968 is shown, and the requirements for future ESA missions (until the late 1980's) are assessed. Timing systems and their configuration at various ESA ground stations and the operations control centers are described. Two studies on future techniques in the field of time dissemination and time synchronization conclude this paper: The LASSO mission (Laser Synchronization from Stationary Orbit) and a low-cost time dissemination technique using METEOSAT, the European meteorological satellites, are briefly outlined.

  6. High-accuracy interferometer with a prism pair for measurement of the absolute refractive index of glass

    SciTech Connect

    Hori, Yasuaki; Hirai, Akiko; Minoshima, Kaoru; Matsumoto, Hirokazu

    2009-04-10

    We propose a variable-path interferometric technique for the measurement of the absolute refractive index of optical glasses. We use two interferometers to decide the ratio between changes in the optical path in a prism-shaped sample glass and in air resulting from displacement of the sample. The method allows precise measurements to be made without prior knowledge of the properties of the sample. The combined standard uncertainty of the proposed method is 1.6x10{sup -6}.

  7. Effects of Accuracy Feedback on Fractal Characteristics of Time Estimation

    PubMed Central

    Kuznetsov, Nikita A.; Wallot, Sebastian

    2011-01-01

    The current experiment investigated the effect of visual accuracy feedback on the structure of variability of time interval estimates in the continuation tapping paradigm. Participants were asked to repeatedly estimate a 1-s interval for a prolonged period of time by tapping their index finger. In some conditions, participants received accuracy feedback after every estimate, whereas in other conditions, no feedback was given. Also, the likelihood of receiving visual feedback was manipulated by adjusting the tolerance band around the 1-s target interval so that feedback was displayed only if the temporal estimate deviated from the target interval by more than 50, 100, or 200 ms respectively. We analyzed the structure of variability of the inter-tap intervals with fractal and multifractal methods that allow for a quantification of complex long-range correlation patterns in the timing performance. Our results indicate that feedback changes the long-range correlation structure of time estimates: Increased amounts of feedback lead to a decrease in fractal long-range correlations, as well to a decrease in the magnitude of local fluctuations in the performance. The multifractal characteristics of the time estimates were not impacted by the presence of accuracy feedback. Nevertheless, most of the data sets show significant multifractal signatures. We interpret these findings as showing that feedback acts to constrain and possibly reorganize timing performance. Implications for mechanistic and complex systems-based theories of timing behavior are discussed. PMID:22046149

  8. Absolute frequency measurement at 10-16 level based on the international atomic time

    NASA Astrophysics Data System (ADS)

    Hachisu, H.; Fujieda, M.; Kumagai, M.; Ido, T.

    2016-06-01

    Referring to International Atomic Time (TAI), we measured the absolute frequency of the 87Sr lattice clock with its uncertainty of 1.1 x 10-15. Unless an optical clock is continuously operated for the five days of the TAI grid, it is required to evaluate dead time uncertainty in order to use the available five-day average of the local frequency reference. We homogeneously distributed intermittent measurements over the five-day grid of TAI, by which the dead time uncertainty was reduced to low 10-16 level. Three campaigns of the five (or four)-day consecutive measurements have resulted in the absolute frequency of the 87Sr clock transition of 429 228 004 229 872.85 (47) Hz, where the systematic uncertainty of the 87Sr optical frequency standard amounts to 8.6 x 10-17.

  9. Absolute value optimization to estimate phase properties of stochastic time series

    NASA Technical Reports Server (NTRS)

    Scargle, J. D.

    1977-01-01

    Most existing deconvolution techniques are incapable of determining phase properties of wavelets from time series data; to assure a unique solution, minimum phase is usually assumed. It is demonstrated, for moving average processes of order one, that deconvolution filtering using the absolute value norm provides an estimate of the wavelet shape that has the correct phase character when the random driving process is nonnormal. Numerical tests show that this result probably applies to more general processes.

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

    NASA Astrophysics Data System (ADS)

    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.

  11. Improved time-domain accuracy standards for model gravitational waveforms

    SciTech Connect

    Lindblom, Lee; Baker, John G.

    2010-10-15

    Model gravitational waveforms must be accurate enough to be useful for detection of signals and measurement of their parameters, so appropriate accuracy standards are needed. Yet these standards should not be unnecessarily restrictive, making them impractical for the numerical and analytical modelers to meet. The work of Lindblom, Owen, and Brown [Phys. Rev. D 78, 124020 (2008)] is extended by deriving new waveform accuracy standards which are significantly less restrictive while still ensuring the quality needed for gravitational-wave data analysis. These new standards are formulated as bounds on certain norms of the time-domain waveform errors, which makes it possible to enforce them in situations where frequency-domain errors may be difficult or impossible to estimate reliably. These standards are less restrictive by about a factor of 20 than the previously published time-domain standards for detection, and up to a factor of 60 for measurement. These new standards should therefore be much easier to use effectively.

  12. Operating a real time high accuracy positioning system

    NASA Astrophysics Data System (ADS)

    Johnston, G.; Hanley, J.; Russell, D.; Vooght, A.

    2003-04-01

    The paper shall review the history and development of real time DGPS services prior to then describing the design of a high accuracy GPS commercial augmentation system and service currently delivering over a wide area to users of precise positioning products. The infrastructure and system shall be explained in relation to the need for high accuracy and high integrity of positioning for users. A comparison of the different techniques for the delivery of data shall be provided to outline the technical approach taken. Examples of the performance of the real time system shall be shown in various regions and modes to outline the current achievable accuracies. Having described and established the current GPS based situation, a review of the potential of the Galileo system shall be presented. Following brief contextual information relating to the Galileo project, core system and services, the paper will identify possible key applications and the main user communities for sub decimetre level precise positioning. The paper will address the Galileo and modernised GPS signals in space that are relevant to commercial precise positioning for the future and will discuss the implications for precise positioning performance. An outline of the proposed architecture shall be described and associated with pointers towards a successful implementation. Central to this discussion will be an assessment of the likely evolution of system infrastructure and user equipment implementation, prospects for new applications and their effect upon the business case for precise positioning services.

  13. Improve the Absolute Accuracy of Ozone Intensities in the 9-11 μm Region via Mw/ir Multi-Wavelength Spectroscopy

    NASA Astrophysics Data System (ADS)

    Yu, Shanshan; Drouin, Brian

    2016-06-01

    Ozone (O_3) is crucial for studies of air quality, human and crop health, and radiative forcing. Spectroscopic remote sensing techniques have been extensively employed to investigate ozone globally and regionally. Infrared intensities of ≤1% accuracy are desired by the remote sensing community. The accuracy of the current state-of-the-art infrared ozone intensities is on the order of 4-10%, resulting in ad hoc intensity scaling factors for consistent atmospheric retrievals. The large uncertainties on the infrared ozone intensities arise from the fact that pure ozone is very difficult to generate and sustain in the laboratory. Best estimates have employed IR/UV cross beam experiments to determine the accurate O_3 volume mixing ratio of the sample through its standard cross section value at 254 nm. This presentation reports our effort to improve the absolute accuracy of ozone intensities in the 9-11 μm region via a transfer of the precision of the rotational dipole moment onto the infrared measurement (MW/IR). Our approach was to use MW/IR cross beam experiments and determine the O_3 mixing ratio through alternately measuring pure rotation ozone lines from 692 to 779 GHz. The uncertainty of these pure rotation line intensities is better than 0.1%. The sample cell was a slow flow cross cell and the total pressure inside the sample cell was maintained constant through a proportional-integral-derivative (PID) flow control. Five infrared O_3 spectra were obtained, with a path length of 3.74 m, pressures ranging from 30 to 120 mTorr, and mixing ratio ranging from 0.5 to 0.9. A multi spectrum fitting technique was employed to fit all the FTS spectra simultaneously. The results show that we can determine intensities of the 9.6μm band with absolute accuracy better than 4%.

  14. Accuracy Assessment in rainfall upscaling in multiple time scales

    NASA Astrophysics Data System (ADS)

    Yu, H.; Wang, C.; Lin, Y.

    2008-12-01

    Long-term hydrologic parameters, e.g. annual precipitations, are usually used to represent the general hydrologic characteristics in a region. Recently, the analysis of the impact of climate change to hydrological patterns primarily relies on the measurement and/or the estimations in long time scales, e.g. year. Under the general condition of the prevalence of short-term measurements, therefore, it is important to understand the accuracy of upscaling for the long-term estimations of hydrologic parameters. This study applies spatiotemporal geostatistical method to analyze and discuss the accuracy of precipitation upscaling in Taiwan under the different time scales, and also quantifies the uncertainty in the upscaled long-term precipitations. In this study, two space-time upscaling approaches developed by Bayesian Maximum Entropy method (BME) are presented 1) UM1: data aggregation followed by BME estimation and 2) UM2: BME estimation followed by aggregation. The investigation and comparison are also implemented to assess the performance of the rainfall estimations in multiple time scales in Taiwan by the two upscaling. Keywords: upscaling, geostatistics, BME, uncertainty analysis

  15. Comparison of different standards for real-time PCR-based absolute quantification.

    PubMed

    Dhanasekaran, S; Doherty, T Mark; Kenneth, John

    2010-03-31

    Quantitative real-time PCR (qPCR) is a powerful tool used for both research and diagnostic, which has the advantage, compared to relative quantification, of providing an absolute copy number for a particular target. However, reliable standards are essential for qPCR. In this study, we have compared four types of commonly-used standards--PCR products (with and without purification) and cloned target sequences (circular and linear plasmid) for their stability during storage (using percentage of variance in copy numbers, PCR efficiency and regression curve correlation coefficient (R(2))) using hydrolysis probe (TaqMan) chemistry. Results, expressed as copy numbers/microl, are presented from a sample human system in which absolute levels of HuPO (reference gene) and the cytokine gene IFN-gamma were measured. To ensure the suitability and stability of the four standards, the experiments were performed at 0, 7 and 14 day intervals and repeated 6 times. We have found that the copy numbers vary (due to degradation of standards) over the period of time during storage at 4 degrees C and -20 degrees C, which affected PCR efficiency significantly. The cloned target sequences were noticeably more stable than the PCR product, which could lead to substantial variance in results using standards constructed by different routes. Standard quality and stability should be routinely tested for assays using qPCR.

  16. Evaluation of absolute quantitation by nonlinear regression in probe-based real-time PCR

    PubMed Central

    Goll, Rasmus; Olsen, Trine; Cui, Guanglin; Florholmen, Jon

    2006-01-01

    Background In real-time PCR data analysis, the cycle threshold (CT) method is currently the gold standard. This method is based on an assumption of equal PCR efficiency in all reactions, and precision may suffer if this condition is not met. Nonlinear regression analysis (NLR) or curve fitting has therefore been suggested as an alternative to the cycle threshold method for absolute quantitation. The advantages of NLR are that the individual sample efficiency is simulated by the model and that absolute quantitation is possible without a standard curve, releasing reaction wells for unknown samples. However, the calculation method has not been evaluated systematically and has not previously been applied to a TaqMan platform. Aim: To develop and evaluate an automated NLR algorithm capable of generating batch production regression analysis. Results Total RNA samples extracted from human gastric mucosa were reverse transcribed and analysed for TNFA, IL18 and ACTB by TaqMan real-time PCR. Fluorescence data were analysed by the regular CT method with a standard curve, and by NLR with a positive control for conversion of fluorescence intensity to copy number, and for this purpose an automated algorithm was written in SPSS syntax. Eleven separate regression models were tested, and the output data was subjected to Altman-Bland analysis. The Altman-Bland analysis showed that the best regression model yielded quantitative data with an intra-assay variation of 58% vs. 24% for the CT derived copy numbers, and with a mean inter-method deviation of × 0.8. Conclusion NLR can be automated for batch production analysis, but the CT method is more precise for absolute quantitation in the present setting. The observed inter-method deviation is an indication that assessment of the fluorescence conversion factor used in the regression method can be improved. However, the versatility depends on the level of precision required, and in some settings the increased cost effectiveness of NLR

  17. Accuracy of real time radiography burning rate measurement

    NASA Astrophysics Data System (ADS)

    Olaniyi, Bisola

    The design of a solid propellant rocket motor requires the determination of a propellant's burning-rate and its dependency upon environmental parameters. The requirement that the burning-rate be physically measured, establishes the need for methods and equipment to obtain such data. A literature review reveals that no measurement has provided the desired burning rate accuracy. In the current study, flash x-ray modeling and digitized film-density data were employed to predict motor-port area to length ratio. The pre-fired port-areas and base burning rate were within 2.5% and 1.2% of their known values, respectively. To verify the accuracy of the method, a continuous x-ray and a solid propellant rocket motor model (Plexiglas cylinder) were used. The solid propellant motor model was translated laterally through a real-time radiography system at different speeds simulating different burning rates. X-ray images were captured and the burning-rate was then determined. The measured burning rate was within 1.65% of the known values.

  18. Calculation of Retention Time Tolerance Windows with Absolute Confidence from Shared Liquid Chromatographic Retention Data

    PubMed Central

    Boswell, Paul G.; Abate-Pella, Daniel; Hewitt, Joshua T.

    2015-01-01

    Compound identification by liquid chromatography-mass spectrometry (LC-MS) is a tedious process, mainly because authentic standards must be run on a user’s system to be able to confidently reject a potential identity from its retention time and mass spectral properties. Instead, it would be preferable to use shared retention time/index data to narrow down the identity, but shared data cannot be used to reject candidates with an absolute level of confidence because the data are strongly affected by differences between HPLC systems and experimental conditions. However, a technique called “retention projection” was recently shown to account for many of the differences. In this manuscript, we discuss an approach to calculate appropriate retention time tolerance windows for projected retention times, potentially making it possible to exclude candidates with an absolute level of confidence, without needing to have authentic standards of each candidate on hand. In a range of multi-segment gradients and flow rates run among seven different labs, the new approach calculated tolerance windows that were significantly more appropriate for each retention projection than global tolerance windows calculated for retention projections or linear retention indices. Though there were still some small differences between the labs that evidently were not taken into account, the calculated tolerance windows only needed to be relaxed by 50% to make them appropriate for all labs. Even then, 42% of the tolerance windows calculated in this study without standards were narrower than those required by WADA for positive identification, where standards must be run contemporaneously. PMID:26292624

  19. Tracking Accuracy of a Real-Time Fiducial Tracking System for Patient Positioning and Monitoring in Radiation Therapy

    SciTech Connect

    Shchory, Tal; Schifter, Dan; Lichtman, Rinat; Neustadter, David; Corn, Benjamin W.

    2010-11-15

    Purpose: In radiation therapy there is a need to accurately know the location of the target in real time. A novel radioactive tracking technology has been developed to answer this need. The technology consists of a radioactive implanted fiducial marker designed to minimize migration and a linac mounted tracking device. This study measured the static and dynamic accuracy of the new tracking technology in a clinical radiation therapy environment. Methods and Materials: The tracking device was installed on the linac gantry. The radioactive marker was located in a tissue equivalent phantom. Marker location was measured simultaneously by the radioactive tracking system and by a Microscribe G2 coordinate measuring machine (certified spatial accuracy of 0.38 mm). Localization consistency throughout a volume and absolute accuracy in the Fixed coordinate system were measured at multiple gantry angles over volumes of at least 10 cm in diameter centered at isocenter. Dynamic accuracy was measured with the marker located inside a breathing phantom. Results: The mean consistency for the static source was 0.58 mm throughout the tested region at all measured gantry angles. The mean absolute position error in the Fixed coordinate system for all gantry angles was 0.97 mm. The mean real-time tracking error for the dynamic source within the breathing phantom was less than 1 mm. Conclusions: This novel radioactive tracking technology has the potential to be useful in accurate target localization and real-time monitoring for radiation therapy.

  20. The Question of Absolute Space and Time Directions in Relation to Molecular Chirality, Parity Violation, and Biomolecular Homochirality

    SciTech Connect

    Quack, Martin

    2001-03-21

    The questions of the absolute directions of space and time or the “observability” of absolute time direction as well as absolute handedness-left or right- are related to the fundamental symmetries of physics C, P, T as well as their combinations, in particular CPT, and their violations, such as parity violation. At the same time there is a relation to certain still open questions in chemistry concerning the fundamental physical- chemical principles of molecular chirality and in biochemistry concerning the selection of homochirality in evolution. In the lecture we shall introduce the concepts and then report new theoretical results from our work on parity violation in chiral molecules, showing order of magnitude increases with respect to previously accepted values. We discus as well our current experimental efforts. We shall briefly mention the construction of an absolute molecular clock.

  1. The Question of Absolute Space and Time Directions in Relation to Molecular Chirality, Parity Violation, and Biomolecular Homochirality

    SciTech Connect

    Quack, Martin

    2001-03-21

    The questions of the absolute directions of space and time or the 'observability' of absolute time direction as well as absolute handedness - left or right - are related to the fundamental symmetries of physics C, P, T as well as their combinations, in particular CPT, and their violations, such as parity violation. At the same time there is a relation to certain still open questions in chemistry concerning the fundamental physical-chemical principles of molecular chirality and in biochemistry concerning the selection of homochirality in evolution. In the lecture we shall introduce the concepts and then report new theoretical results from our work on parity violation in chiral molecules, showing order of magnitude increases with respect to previously accepted values. We discuss as well our current experimental efforts. We shall briefly mention the construction of an absolute molecular clock.

  2. Alignment between seafloor spreading directions and absolute plate motions through time

    NASA Astrophysics Data System (ADS)

    Williams, Simon E.; Flament, Nicolas; Müller, R. Dietmar

    2016-02-01

    The history of seafloor spreading in the ocean basins provides a detailed record of relative motions between Earth's tectonic plates since Pangea breakup. Determining how tectonic plates have moved relative to the Earth's deep interior is more challenging. Recent studies of contemporary plate motions have demonstrated links between relative plate motion and absolute plate motion (APM), and with seismic anisotropy in the upper mantle. Here we explore the link between spreading directions and APM since the Early Cretaceous. We find a significant alignment between APM and spreading directions at mid-ocean ridges; however, the degree of alignment is influenced by geodynamic setting, and is strongest for mid-Atlantic spreading ridges between plates that are not directly influenced by time-varying slab pull. In the Pacific, significant mismatches between spreading and APM direction may relate to a major plate-mantle reorganization. We conclude that spreading fabric can be used to improve models of APM.

  3. A California statewide three-dimensional seismic velocity model from both absolute and differential times

    USGS Publications Warehouse

    Lin, G.; Thurber, C.H.; Zhang, H.; Hauksson, E.; Shearer, P.M.; Waldhauser, F.; Brocher, T.M.; Hardebeck, J.

    2010-01-01

    We obtain a seismic velocity model of the California crust and uppermost mantle using a regional-scale double-difference tomography algorithm. We begin by using absolute arrival-time picks to solve for a coarse three-dimensional (3D) P velocity (VP) model with a uniform 30 km horizontal node spacing, which we then use as the starting model for a finer-scale inversion using double-difference tomography applied to absolute and differential pick times. For computational reasons, we split the state into 5 subregions with a grid spacing of 10 to 20 km and assemble our final statewide VP model by stitching together these local models. We also solve for a statewide S-wave model using S picks from both the Southern California Seismic Network and USArray, assuming a starting model based on the VP results and a VP=VS ratio of 1.732. Our new model has improved areal coverage compared with previous models, extending 570 km in the SW-NE directionand 1320 km in the NW-SE direction. It also extends to greater depth due to the inclusion of substantial data at large epicentral distances. Our VP model generally agrees with previous separate regional models for northern and southern California, but we also observe some new features, such as high-velocity anomalies at shallow depths in the Klamath Mountains and Mount Shasta area, somewhat slow velocities in the northern Coast Ranges, and slow anomalies beneath the Sierra Nevada at midcrustal and greater depths. This model can be applied to a variety of regional-scale studies in California, such as developing a unified statewide earthquake location catalog and performing regional waveform modeling.

  4. Time-resolved spectral imaging: better photon economy, higher accuracy

    NASA Astrophysics Data System (ADS)

    Fereidouni, Farzad; Reitsma, Keimpe; Blab, Gerhard A.; Gerritsen, Hans C.

    2015-03-01

    Lifetime and spectral imaging are complementary techniques that offer a non-invasive solution for monitoring metabolic processes, identifying biochemical compounds, and characterizing their interactions in biological tissues, among other tasks. Newly developed instruments that perform time-resolved spectral imaging can provide even more information and reach higher sensitivity than either modality alone. Here we report a multispectral lifetime imaging system based on a field-programmable gate array (FPGA), capable of operating at high photon count rates (12 MHz) per spectral detection channel, and with time resolution of 200 ps. We performed error analyses to investigate the effect of gate width and spectral-channel width on the accuracy of estimated lifetimes and spectral widths. Temporal and spectral phasors were used for analysis of recorded data, and we demonstrated blind un-mixing of the fluorescent components using information from both modalities. Fractional intensities, spectra, and decay curves of components were extracted without need for prior information. We further tested this approach with fluorescently doubly-labeled DNA, and demonstrated its suitability for accurately estimating FRET efficiency in the presence of either non-interacting or interacting donor molecules.

  5. Absolute calibration method for nanosecond-resolved, time-streaked, fiber optic light collection, spectroscopy systems

    NASA Astrophysics Data System (ADS)

    Johnston, Mark D.; Oliver, Bryan V.; Droemer, Darryl W.; Frogget, Brent; Crain, Marlon D.; Maron, Yitzhak

    2012-08-01

    This paper describes a convenient and accurate method to calibrate fast (<1 ns resolution) streaked, fiber optic light collection, spectroscopy systems. Such systems are inherently difficult to calibrate due to the lack of sufficiently intense, calibrated light sources. Such a system is used to collect spectral data on plasmas generated in electron beam diodes fielded on the RITS-6 accelerator (8-12MV, 140-200kA) at Sandia National Laboratories. On RITS, plasma light is collected through a small diameter (200 μm) optical fiber and recorded on a fast streak camera at the output of a 1 meter Czerny-Turner monochromator. For this paper, a 300 W xenon short arc lamp (Oriel Model 6258) was used as the calibration source. Since the radiance of the xenon arc varies from cathode to anode, just the area around the tip of the cathode ("hotspot") was imaged onto the fiber, to produce the highest intensity output. To compensate for chromatic aberrations, the signal was optimized at each wavelength measured. Output power was measured using 10 nm bandpass interference filters and a calibrated photodetector. These measurements give power at discrete wavelengths across the spectrum, and when linearly interpolated, provide a calibration curve for the lamp. The shape of the spectrum is determined by the collective response of the optics, monochromator, and streak tube across the spectral region of interest. The ratio of the spectral curve to the measured bandpass filter curve at each wavelength produces a correction factor (Q) curve. This curve is then applied to the experimental data and the resultant spectra are given in absolute intensity units (photons/sec/cm2/steradian/nm). Error analysis shows this method to be accurate to within +/- 20%, which represents a high level of accuracy for this type of measurement.

  6. Absolute calibration method for nanosecond-resolved, time-streaked, fiber optic light collection, spectroscopy systems.

    PubMed

    Johnston, Mark D; Oliver, Bryan V; Droemer, Darryl W; Frogget, Brent; Crain, Marlon D; Maron, Yitzhak

    2012-08-01

    This paper describes a convenient and accurate method to calibrate fast (<1 ns resolution) streaked, fiber optic light collection, spectroscopy systems. Such systems are inherently difficult to calibrate due to the lack of sufficiently intense, calibrated light sources. Such a system is used to collect spectral data on plasmas generated in electron beam diodes fielded on the RITS-6 accelerator (8-12MV, 140-200kA) at Sandia National Laboratories. On RITS, plasma light is collected through a small diameter (200 μm) optical fiber and recorded on a fast streak camera at the output of a 1 meter Czerny-Turner monochromator. For this paper, a 300 W xenon short arc lamp (Oriel Model 6258) was used as the calibration source. Since the radiance of the xenon arc varies from cathode to anode, just the area around the tip of the cathode ("hotspot") was imaged onto the fiber, to produce the highest intensity output. To compensate for chromatic aberrations, the signal was optimized at each wavelength measured. Output power was measured using 10 nm bandpass interference filters and a calibrated photodetector. These measurements give power at discrete wavelengths across the spectrum, and when linearly interpolated, provide a calibration curve for the lamp. The shape of the spectrum is determined by the collective response of the optics, monochromator, and streak tube across the spectral region of interest. The ratio of the spectral curve to the measured bandpass filter curve at each wavelength produces a correction factor (Q) curve. This curve is then applied to the experimental data and the resultant spectra are given in absolute intensity units (photons/sec/cm(2)/steradian/nm). Error analysis shows this method to be accurate to within +∕- 20%, which represents a high level of accuracy for this type of measurement. PMID:22938275

  7. An Integrated Model of Choices and Response Times in Absolute Identification

    ERIC Educational Resources Information Center

    Brown, Scott D.; Marley, A. A. J.; Donkin, Christopher; Heathcote, Andrew

    2008-01-01

    Recent theoretical developments in the field of absolute identification have stressed differences between relative and absolute processes, that is, whether stimulus magnitudes are judged relative to a shorter term context provided by recently presented stimuli or a longer term context provided by the entire set of stimuli. The authors developed a…

  8. Model-based evaluation of microbial mass fractions: effect of absolute anaerobic reaction time on microbial mass fractions.

    PubMed

    Tunçal, Tolga

    2010-04-14

    Although enhanced biological phosphorus removal processes (EBPR) are popular methods for nutrient control, unstable treatment performances of full-scale systems are still not well understood. In this study, the interaction between electron acceptors present at the start of the anaerobic phase of an EBPR system and the amount of organic acids generated from simple substrate (rbsCOD) was investigated in a full-scale wastewater treatment plant. Quantification of microbial groups including phosphorus-accumulating microorganisms (PAOs), denitrifying PAOs (DPAOs), glycogen-accumulating microorganisms (GAOs) and ordinary heterotrophic microorganisms (OHOs) was based on a modified dynamic model. The intracellular phosphorus content of PAOs was also determined by the execution of mass balances for the biological stages of the plant. The EBPR activities observed in the plant and in batch tests (under idealized conditions) were compared with each other statistically as well. Modelling efforts indicated that the use of absolute anaerobic reaction (eta1) instead of nominal anaerobic reaction time (eta), to estimate the amount of available substrate for PAOs, significantly improved model accuracy. Another interesting result of the study was the differences in EBPR characteristics observed in idealized and real conditions. PMID:20480829

  9. Easy Absolute Values? Absolutely

    ERIC Educational Resources Information Center

    Taylor, Sharon E.; Mittag, Kathleen Cage

    2015-01-01

    The authors teach a problem-solving course for preservice middle-grades education majors that includes concepts dealing with absolute-value computations, equations, and inequalities. Many of these students like mathematics and plan to teach it, so they are adept at symbolic manipulations. Getting them to think differently about a concept that they…

  10. Supercontinent cycles and the calculation of absolute palaeolongitude in deep time.

    PubMed

    Mitchell, Ross N; Kilian, Taylor M; Evans, David A D

    2012-02-08

    Traditional models of the supercontinent cycle predict that the next supercontinent--'Amasia'--will form either where Pangaea rifted (the 'introversion' model) or on the opposite side of the world (the 'extroversion' models). Here, by contrast, we develop an 'orthoversion' model whereby a succeeding supercontinent forms 90° away, within the great circle of subduction encircling its relict predecessor. A supercontinent aggregates over a mantle downwelling but then influences global-scale mantle convection to create an upwelling under the landmass. We calculate the minimum moment of inertia about which oscillatory true polar wander occurs owing to the prolate shape of the non-hydrostatic Earth. By fitting great circles to each supercontinent's true polar wander legacy, we determine that the arc distances between successive supercontinent centres (the axes of the respective minimum moments of inertia) are 88° for Nuna to Rodinia and 87° for Rodinia to Pangaea--as predicted by the orthoversion model. Supercontinent centres can be located back into Precambrian time, providing fixed points for the calculation of absolute palaeolongitude over billion-year timescales. Palaeogeographic reconstructions additionally constrained in palaeolongitude will provide increasingly accurate estimates of ancient plate motions and palaeobiogeographic affinities.

  11. Supercontinent cycles and the calculation of absolute palaeolongitude in deep time.

    PubMed

    Mitchell, Ross N; Kilian, Taylor M; Evans, David A D

    2012-02-01

    Traditional models of the supercontinent cycle predict that the next supercontinent--'Amasia'--will form either where Pangaea rifted (the 'introversion' model) or on the opposite side of the world (the 'extroversion' models). Here, by contrast, we develop an 'orthoversion' model whereby a succeeding supercontinent forms 90° away, within the great circle of subduction encircling its relict predecessor. A supercontinent aggregates over a mantle downwelling but then influences global-scale mantle convection to create an upwelling under the landmass. We calculate the minimum moment of inertia about which oscillatory true polar wander occurs owing to the prolate shape of the non-hydrostatic Earth. By fitting great circles to each supercontinent's true polar wander legacy, we determine that the arc distances between successive supercontinent centres (the axes of the respective minimum moments of inertia) are 88° for Nuna to Rodinia and 87° for Rodinia to Pangaea--as predicted by the orthoversion model. Supercontinent centres can be located back into Precambrian time, providing fixed points for the calculation of absolute palaeolongitude over billion-year timescales. Palaeogeographic reconstructions additionally constrained in palaeolongitude will provide increasingly accurate estimates of ancient plate motions and palaeobiogeographic affinities. PMID:22318605

  12. A quantitative method for evaluating numerical simulation accuracy of time-transient Lamb wave propagation with its applications to selecting appropriate element size and time step.

    PubMed

    Wan, Xiang; Xu, Guanghua; Zhang, Qing; Tse, Peter W; Tan, Haihui

    2016-01-01

    Lamb wave technique has been widely used in non-destructive evaluation (NDE) and structural health monitoring (SHM). However, due to the multi-mode characteristics and dispersive nature, Lamb wave propagation behavior is much more complex than that of bulk waves. Numerous numerical simulations on Lamb wave propagation have been conducted to study its physical principles. However, few quantitative studies on evaluating the accuracy of these numerical simulations were reported. In this paper, a method based on cross correlation analysis for quantitatively evaluating the simulation accuracy of time-transient Lamb waves propagation is proposed. Two kinds of error, affecting the position and shape accuracies are firstly identified. Consequently, two quantitative indices, i.e., the GVE (group velocity error) and MACCC (maximum absolute value of cross correlation coefficient) derived from cross correlation analysis between a simulated signal and a reference waveform, are proposed to assess the position and shape errors of the simulated signal. In this way, the simulation accuracy on the position and shape is quantitatively evaluated. In order to apply this proposed method to select appropriate element size and time step, a specialized 2D-FEM program combined with the proposed method is developed. Then, the proper element size considering different element types and time step considering different time integration schemes are selected. These results proved that the proposed method is feasible and effective, and can be used as an efficient tool for quantitatively evaluating and verifying the simulation accuracy of time-transient Lamb wave propagation. PMID:26315506

  13. Vehicle Position Estimation Based on Magnetic Markers: Enhanced Accuracy by Compensation of Time Delays

    PubMed Central

    Byun, Yeun-Sub; Jeong, Rag-Gyo; Kang, Seok-Won

    2015-01-01

    The real-time recognition of absolute (or relative) position and orientation on a network of roads is a core technology for fully automated or driving-assisted vehicles. This paper presents an empirical investigation of the design, implementation, and evaluation of a self-positioning system based on a magnetic marker reference sensing method for an autonomous vehicle. Specifically, the estimation accuracy of the magnetic sensing ruler (MSR) in the up-to-date estimation of the actual position was successfully enhanced by compensating for time delays in signal processing when detecting the vertical magnetic field (VMF) in an array of signals. In this study, the signal processing scheme was developed to minimize the effects of the distortion of measured signals when estimating the relative positional information based on magnetic signals obtained using the MSR. In other words, the center point in a 2D magnetic field contour plot corresponding to the actual position of magnetic markers was estimated by tracking the errors between pre-defined reference models and measured magnetic signals. The algorithm proposed in this study was validated by experimental measurements using a test vehicle on a pilot network of roads. From the results, the positioning error was found to be less than 0.04 m on average in an operational test. PMID:26580622

  14. Vehicle Position Estimation Based on Magnetic Markers: Enhanced Accuracy by Compensation of Time Delays.

    PubMed

    Byun, Yeun-Sub; Jeong, Rag-Gyo; Kang, Seok-Won

    2015-01-01

    The real-time recognition of absolute (or relative) position and orientation on a network of roads is a core technology for fully automated or driving-assisted vehicles. This paper presents an empirical investigation of the design, implementation, and evaluation of a self-positioning system based on a magnetic marker reference sensing method for an autonomous vehicle. Specifically, the estimation accuracy of the magnetic sensing ruler (MSR) in the up-to-date estimation of the actual position was successfully enhanced by compensating for time delays in signal processing when detecting the vertical magnetic field (VMF) in an array of signals. In this study, the signal processing scheme was developed to minimize the effects of the distortion of measured signals when estimating the relative positional information based on magnetic signals obtained using the MSR. In other words, the center point in a 2D magnetic field contour plot corresponding to the actual position of magnetic markers was estimated by tracking the errors between pre-defined reference models and measured magnetic signals. The algorithm proposed in this study was validated by experimental measurements using a test vehicle on a pilot network of roads. From the results, the positioning error was found to be less than 0.04 m on average in an operational test. PMID:26580622

  15. Real-Time Determination of Absolute Frequency in Continuous-Wave Terahertz Radiation with a Photocarrier Terahertz Frequency Comb Induced by an Unstabilized Femtosecond Laser

    NASA Astrophysics Data System (ADS)

    Minamikawa, Takeo; Hayashi, Kenta; Mizuguchi, Tatsuya; Hsieh, Yi-Da; Abdelsalam, Dahi Ghareab; Mizutani, Yasuhiro; Yamamoto, Hirotsugu; Iwata, Tetsuo; Yasui, Takeshi

    2016-05-01

    A practical method for the absolute frequency measurement of continuous-wave terahertz (CW-THz) radiation uses a photocarrier terahertz frequency comb (PC-THz comb) because of its ability to realize real-time, precise measurement without the need for cryogenic cooling. However, the requirement for precise stabilization of the repetition frequency ( f rep) and/or use of dual femtosecond lasers hinders its practical use. In this article, based on the fact that an equal interval between PC-THz comb modes is always maintained regardless of the fluctuation in f rep, the PC-THz comb induced by an unstabilized laser was used to determine the absolute frequency f THz of CW-THz radiation. Using an f rep-free-running PC-THz comb, the f THz of the frequency-fixed or frequency-fluctuated active frequency multiplier chain CW-THz source was determined at a measurement rate of 10 Hz with a relative accuracy of 8.2 × 10-13 and a relative precision of 8.8 × 10-12 to a rubidium frequency standard. Furthermore, f THz was correctly determined even when fluctuating over a range of 20 GHz. The proposed method enables the use of any commercial femtosecond laser for the absolute frequency measurement of CW-THz radiation.

  16. Interference peak detection based on FPGA for real-time absolute distance ranging with dual-comb lasers

    NASA Astrophysics Data System (ADS)

    Ni, Kai; Dong, Hao; Zhou, Qian; Xu, Mingfei; Li, Xinghui; Wu, Guanhao

    2015-08-01

    Absolute distance measurement using dual femtosecond comb lasers can achieve higher accuracy and faster measurement speed, which makes it more and more attractive. The data processing flow consists of four steps: interference peak detection, fast Fourier transform (FFT), phase fitting and compensation of index of refraction. A realtime data processing system based on Field-Programmable Gate Array (FPGA) for dual-comb ranging has been newly developed. The design and implementation of the interference peak detection algorithm by FPGA and Verilog language is introduced in this paper, which is viewed as the most complicated part and an important guarantee for system precision and reliability. An adaptive sliding window for scanning is used to detect peaks. In the process of detection, the algorithm stores 16 sample data as a detection unit and calculates the average of each unit. The average result is used to determine the vertical center height of the sliding window. The algorithm estimates the noise intensity of each detection unit, and then calculates the average of the noise strength of successive 128 units. The noise average is used to calculate the signal to noise ratio of the current working environment, which is used to adjust the height of the sliding window. This adaptive sliding window helps to eliminate fake peaks caused by noise. The whole design is based on the way of pipeline, which can improves the real-time throughput of the overall peak detection module. Its execution speed is up to 140MHz in the FPGA, and the peak can be detected in 16 clock cycle when it appears.

  17. Measurement of the Absolute Magnitude and Time Courses of Mitochondrial Membrane Potential in Primary and Clonal Pancreatic Beta-Cells.

    PubMed

    Gerencser, Akos A; Mookerjee, Shona A; Jastroch, Martin; Brand, Martin D

    2016-01-01

    The aim of this study was to simplify, improve and validate quantitative measurement of the mitochondrial membrane potential (ΔψM) in pancreatic β-cells. This built on our previously introduced calculation of the absolute magnitude of ΔψM in intact cells, using time-lapse imaging of the non-quench mode fluorescence of tetramethylrhodamine methyl ester and a bis-oxonol plasma membrane potential (ΔψP) indicator. ΔψM is a central mediator of glucose-stimulated insulin secretion in pancreatic β-cells. ΔψM is at the crossroads of cellular energy production and demand, therefore precise assay of its magnitude is a valuable tool to study how these processes interplay in insulin secretion. Dispersed islet cell cultures allowed cell type-specific, single-cell observations of cell-to-cell heterogeneity of ΔψM and ΔψP. Glucose addition caused hyperpolarization of ΔψM and depolarization of ΔψP. The hyperpolarization was a monophasic step increase, even in cells where the ΔψP depolarization was biphasic. The biphasic response of ΔψP was associated with a larger hyperpolarization of ΔψM than the monophasic response. Analysis of the relationships between ΔψP and ΔψM revealed that primary dispersed β-cells responded to glucose heterogeneously, driven by variable activation of energy metabolism. Sensitivity analysis of the calibration was consistent with β-cells having substantial cell-to-cell variations in amounts of mitochondria, and this was predicted not to impair the accuracy of determinations of relative changes in ΔψM and ΔψP. Finally, we demonstrate a significant problem with using an alternative ΔψM probe, rhodamine 123. In glucose-stimulated and oligomycin-inhibited β-cells the principles of the rhodamine 123 assay were breached, resulting in misleading conclusions.

  18. A BAYESIAN METHOD FOR CALCULATING REAL-TIME QUANTITATIVE PCR CALIBRATION CURVES USING ABSOLUTE PLASMID DNA STANDARDS

    EPA Science Inventory

    In real-time quantitative PCR studies using absolute plasmid DNA standards, a calibration curve is developed to estimate an unknown DNA concentration. However, potential differences in the amplification performance of plasmid DNA compared to genomic DNA standards are often ignore...

  19. Influence of GPS/GLONASS differential code biases on the determination accuracy of the absolute total electron content in the ionosphere

    NASA Astrophysics Data System (ADS)

    Yasyukevich, Yu. V.; Mylnikova, A. A.; Kunitsyn, V. E.; Padokhin, A. M.

    2015-11-01

    Systematic error arises when the total electron content (TEC) is estimated with the simultaneous use of phase and code GPS/GLONASS measurements. This is related to the different signal propagation times at L1 and L2 frequencies in the radio frequency path of the transmitting and receiving equipment, the so-called differential code biases. A differential code bias of 1 ns results in an error of ~2.9 TECU when TEC is determined. Differential code bias variations on a long time interval, which were obtained at the CODE laboratory, were analyzed. It has been found that the systematic variation in these biases and considerable seasonal variations apparently caused by the environmental state (temperature and humidity), which sometimes reach 20 TECU (in TEC units), are observed for several stations. The algorithm for determining differential code biases at an individual station and the results of correction for absolute slant TEC are also presented. Presented results show algorithm effectiveness for various geographical regions and solar activity.

  20. Advantages of improved timing accuracy in PET cameras using LSOscintillator

    SciTech Connect

    Moses, William W.

    2002-12-02

    PET scanners based on LSO have the potential forsignificantly better coincidence timing resolution than the 6 ns fwhmtypically achieved with BGO. This study analyzes the performanceenhancements made possible by improved timing as a function of thecoincidence time resolution. If 500 ps fwhm coincidence timing resolutioncan be achieved in a complete PET camera, the following four benefits canbe realized for whole-body FDG imaging: 1) The random event rate can bereduced by using a narrower coincidence timing window, increasing thepeak NECR by~;50 percent. 2) Using time-of-flight in the reconstructionalgorithm will reduce the noise variance by a factor of 5. 3) Emissionand transmission data can be acquired simultaneously, reducing the totalscan time. 4) Axial blurring can be reduced by using time-of-flight todetermine the correct axial plane that each event originated from. Whiletime-of-flight was extensively studied in the 1980's, practical factorslimited its effectiveness at that time and little attention has been paidto timing in PET since then. As these potential improvements aresubstantial and the advent of LSO PET cameras gives us the means toobtain them without other sacrifices, efforts to improve PET timingshould resume after their long dormancy.

  1. Accuracy Study of the Space-Time CE/SE Method for Computational Aeroacoustics Problems Involving Shock Waves

    NASA Technical Reports Server (NTRS)

    Wang, Xiao Yen; Chang, Sin-Chung; Jorgenson, Philip C. E.

    1999-01-01

    The space-time conservation element and solution element(CE/SE) method is used to study the sound-shock interaction problem. The order of accuracy of numerical schemes is investigated. The linear model problem.govemed by the 1-D scalar convection equation, sound-shock interaction problem governed by the 1-D Euler equations, and the 1-D shock-tube problem which involves moving shock waves and contact surfaces are solved to investigate the order of accuracy of numerical schemes. It is concluded that the accuracy of the CE/SE numerical scheme with designed 2nd-order accuracy becomes 1st order when a moving shock wave exists. However, the absolute error in the CE/SE solution downstream of the shock wave is on the same order as that obtained using a fourth-order accurate essentially nonoscillatory (ENO) scheme. No special techniques are used for either high-frequency low-amplitude waves or shock waves.

  2. Accuracy in Recalling Interest Inventory Information at Three Time Intervals

    ERIC Educational Resources Information Center

    Swanson, Jane L.; Gore, Paul A., Jr.; Leuwerke, Wade; D'Achiardi, Catalina; Edwards, Jorie Hitch; Edwards, Jared

    2006-01-01

    Rates of accurate recall of the Strong Interest Inventory (SII; L. W. Harmon, J. C. Hansen, F. H. Borgen, & A. L. Hammer, 1994) profile information varied with the amount of time elapsed since the interpretation, the type of SII scale, and whether immediate recall was elicited, but rates did not vary with the strategy used to provide the…

  3. Measurement of the Absolute Magnitude and Time Courses of Mitochondrial Membrane Potential in Primary and Clonal Pancreatic Beta-Cells.

    PubMed

    Gerencser, Akos A; Mookerjee, Shona A; Jastroch, Martin; Brand, Martin D

    2016-01-01

    The aim of this study was to simplify, improve and validate quantitative measurement of the mitochondrial membrane potential (ΔψM) in pancreatic β-cells. This built on our previously introduced calculation of the absolute magnitude of ΔψM in intact cells, using time-lapse imaging of the non-quench mode fluorescence of tetramethylrhodamine methyl ester and a bis-oxonol plasma membrane potential (ΔψP) indicator. ΔψM is a central mediator of glucose-stimulated insulin secretion in pancreatic β-cells. ΔψM is at the crossroads of cellular energy production and demand, therefore precise assay of its magnitude is a valuable tool to study how these processes interplay in insulin secretion. Dispersed islet cell cultures allowed cell type-specific, single-cell observations of cell-to-cell heterogeneity of ΔψM and ΔψP. Glucose addition caused hyperpolarization of ΔψM and depolarization of ΔψP. The hyperpolarization was a monophasic step increase, even in cells where the ΔψP depolarization was biphasic. The biphasic response of ΔψP was associated with a larger hyperpolarization of ΔψM than the monophasic response. Analysis of the relationships between ΔψP and ΔψM revealed that primary dispersed β-cells responded to glucose heterogeneously, driven by variable activation of energy metabolism. Sensitivity analysis of the calibration was consistent with β-cells having substantial cell-to-cell variations in amounts of mitochondria, and this was predicted not to impair the accuracy of determinations of relative changes in ΔψM and ΔψP. Finally, we demonstrate a significant problem with using an alternative ΔψM probe, rhodamine 123. In glucose-stimulated and oligomycin-inhibited β-cells the principles of the rhodamine 123 assay were breached, resulting in misleading conclusions. PMID:27404273

  4. Measurement of the Absolute Magnitude and Time Courses of Mitochondrial Membrane Potential in Primary and Clonal Pancreatic Beta-Cells

    PubMed Central

    Gerencser, Akos A.; Mookerjee, Shona A.; Jastroch, Martin; Brand, Martin D.

    2016-01-01

    The aim of this study was to simplify, improve and validate quantitative measurement of the mitochondrial membrane potential (ΔψM) in pancreatic β-cells. This built on our previously introduced calculation of the absolute magnitude of ΔψM in intact cells, using time-lapse imaging of the non-quench mode fluorescence of tetramethylrhodamine methyl ester and a bis-oxonol plasma membrane potential (ΔψP) indicator. ΔψM is a central mediator of glucose-stimulated insulin secretion in pancreatic β-cells. ΔψM is at the crossroads of cellular energy production and demand, therefore precise assay of its magnitude is a valuable tool to study how these processes interplay in insulin secretion. Dispersed islet cell cultures allowed cell type-specific, single-cell observations of cell-to-cell heterogeneity of ΔψM and ΔψP. Glucose addition caused hyperpolarization of ΔψM and depolarization of ΔψP. The hyperpolarization was a monophasic step increase, even in cells where the ΔψP depolarization was biphasic. The biphasic response of ΔψP was associated with a larger hyperpolarization of ΔψM than the monophasic response. Analysis of the relationships between ΔψP and ΔψM revealed that primary dispersed β-cells responded to glucose heterogeneously, driven by variable activation of energy metabolism. Sensitivity analysis of the calibration was consistent with β-cells having substantial cell-to-cell variations in amounts of mitochondria, and this was predicted not to impair the accuracy of determinations of relative changes in ΔψM and ΔψP. Finally, we demonstrate a significant problem with using an alternative ΔψM probe, rhodamine 123. In glucose-stimulated and oligomycin-inhibited β-cells the principles of the rhodamine 123 assay were breached, resulting in misleading conclusions. PMID:27404273

  5. A mixture hierarchical model for response times and response accuracy.

    PubMed

    Wang, Chun; Xu, Gongjun

    2015-11-01

    In real testing, examinees may manifest different types of test-taking behaviours. In this paper we focus on two types that appear to be among the more frequently occurring behaviours – solution behaviour and rapid guessing behaviour. Rapid guessing usually happens in high-stakes tests when there is insufficient time, and in low-stakes tests when there is lack of effort. These two qualitatively different test-taking behaviours, if ignored, will lead to violation of the local independence assumption and, as a result, yield biased item/person parameter estimation. We propose a mixture hierarchical model to account for differences among item responses and response time patterns arising from these two behaviours. The model is also able to identify the specific behaviour an examinee engages in when answering an item. A Monte Carlo expectation maximization algorithm is proposed for model calibration. A simulation study shows that the new model yields more accurate item and person parameter estimates than a non-mixture model when the data indeed come from two types of behaviour. The model also fits real, high-stakes test data better than a non-mixture model, and therefore the new model can better identify the underlying test-taking behaviour an examinee engages in on a certain item. PMID:25873487

  6. Real-time lens distortion correction: speed, accuracy and efficiency

    NASA Astrophysics Data System (ADS)

    Bax, Michael R.; Shahidi, Ramin

    2014-11-01

    Optical lens systems suffer from nonlinear geometrical distortion. Optical imaging applications such as image-enhanced endoscopy and image-based bronchoscope tracking require correction of this distortion for accurate localization, tracking, registration, and measurement of image features. Real-time capability is desirable for interactive systems and live video. The use of a texture-mapping graphics accelerator, which is standard hardware on current motherboard chipsets and add-in video graphics cards, to perform distortion correction is proposed. Mesh generation for image tessellation, an error analysis, and performance results are presented. It is shown that distortion correction using commodity graphics hardware is substantially faster than using the main processor and can be performed at video frame rates (faster than 30 frames per second), and that the polar-based method of mesh generation proposed here is more accurate than a conventional grid-based approach. Using graphics hardware to perform distortion correction is not only fast and accurate but also efficient as it frees the main processor for other tasks, which is an important issue in some real-time applications.

  7. The accuracy of telling time via oscillatory signals

    NASA Astrophysics Data System (ADS)

    Monti, Michele; Rein ten Wolde, Pieter

    2016-06-01

    Circadian clocks are the central timekeepers of life, allowing cells to anticipate changes between day and night. Experiments in recent years have revealed that circadian clocks can be highly stable, raising the question how reliably they can be read out. Here, we combine mathematical modeling with information theory to address the question how accurately a cell can infer the time from an ensemble of protein oscillations, which are driven by a circadian clock. We show that the precision increases with the number of oscillations and their amplitude relative to their noise. Our analysis also reveals that their exists an optimal phase relation that minimizes the error in the estimate of time, which depends on the relative noise levels of the protein oscillations. Lastly, our work shows that cross-correlations in the noise of the protein oscillations can enhance the mutual information, which suggests that cross-regulatory interactions between the proteins that read out the clock can be beneficial for temporal information transmission.

  8. Modeling Reaction Time and Accuracy of Multiple-Alternative Decisions

    PubMed Central

    Leite, Fábio P.; Ratcliff, Roger

    2009-01-01

    Several sequential sampling models using racing diffusion processes for multiple-alternative decisions were evaluated using data from two perceptual discrimination experiments. The structures of the models differed on a number of dimensions, including whether there was lateral inhibition between accumulators, whether there was decay in evidence, whether evidence could be negative, and whether there was variability in starting points. Data were collected from a letter discrimination task in which stimulus difficulty and probability of the response alternatives were varied along with number of response alternatives. Model fitting results ruled out a large number of model classes in favor of a smaller number of specific models, most of which showed a moderate to high degree of mimicking. The best-fitting models had zero to moderate values of decay, no inhibition, and assumed that the addition of alternatives either affected the subprocesses contributing to the nondecisional time, the degree of caution, or the quality of evidence extracted from stimuli. PMID:20045893

  9. Accuracy vs. computational time: translating aortic simulations to the clinic.

    PubMed

    Brown, Alistair G; Shi, Yubing; Marzo, Alberto; Staicu, Cristina; Valverde, Isra; Beerbaum, Philipp; Lawford, Patricia V; Hose, D Rodney

    2012-02-01

    State of the art simulations of aortic haemodynamics feature full fluid-structure interaction (FSI) and coupled 0D boundary conditions. Such analyses require not only significant computational resource but also weeks to months of run time, which compromises the effectiveness of their translation to a clinical workflow. This article employs three computational fluid methodologies, of varying levels of complexity with coupled 0D boundary conditions, to simulate the haemodynamics within a patient-specific aorta. The most comprehensive model is a full FSI simulation. The simplest is a rigid walled incompressible fluid simulation while an alternative middle-ground approach employs a compressible fluid, tuned to elicit a response analogous to the compliance of the aortic wall. The results demonstrate that, in the context of certain clinical questions, the simpler analysis methods may capture the important characteristics of the flow field.

  10. Posterior Predictive Checks for Conditional Independence between Response Time and Accuracy

    ERIC Educational Resources Information Center

    Bolsinova, Maria; Tijmstra, Jesper

    2016-01-01

    Conditional independence (CI) between response time and response accuracy is a fundamental assumption of many joint models for time and accuracy used in educational measurement. In this study, posterior predictive checks (PPCs) are proposed for testing this assumption. These PPCs are based on three discrepancy measures reflecting different…

  11. A Joint Modeling Approach for Reaction Time and Accuracy in Psycholinguistic Experiments

    ERIC Educational Resources Information Center

    Loeys, T.; Rosseel, Y.; Baten, K.

    2011-01-01

    In the psycholinguistic literature, reaction times and accuracy can be analyzed separately using mixed (logistic) effects models with crossed random effects for item and subject. Given the potential correlation between these two outcomes, a joint model for the reaction time and accuracy may provide further insight. In this paper, a Bayesian…

  12. Verification of concentration time formulae accuracy in Southern Brazil

    NASA Astrophysics Data System (ADS)

    Freitas Ferreira, Pedro; Allasia, Daniel; Herbstrith Froemming, Gabriel; Ribeiro Fontoura, Jessica; Tassi, Rutineia

    2016-04-01

    The time of concentration (TC) of an urban catchment is a fundamental watershed parameter used to compute the peak discharge and/or in the hydrological simulation of sewer systems. In the lack of hydrological data for its estimative, several empirical formulae are used, however, almost none of them have been verified in Brazil leading to large uncertainties in the correct value. In this light, were tested several formulae such as the proposed by Kirpich (and a modifications of this equation proposed by the National Transport Bureau of Brazil (DNIT)), U.S. Corps. Of Engineers, Pasini, Dooge , Johnstone , Ventura and Ven T Chow as they are used in Brazil. The verification was accomplished against measured data in 5 sub-basins situated in the Dilúvio basin, a semi urbanized watershed that contains the most developed area of the city of Porto Alegre. All the rainfall stations were active in the period from late 1970's until early 1980's due to the existence of Projeto Dilúvio but today, however, only two of them are still in operation. Porto Alegre is the capital and largest city in the Brazilian southernmost state of Rio Grande do Sul with a population of approximately 1.6 million inhabitants, the tenth most populous city in the country and the centre of Brazil's fourth largest metropolitan area, with almost 4,5 million inhabitants (IBGE, 2010). The city is situated in a humid subtropical climate with high and regular precipitation throughout the year. Most summer rainfall occurs during thunderstorms and an occasional tropical storm, hurricane or cyclone. The results showed an error of around 70% for half of the formulas, with a tendency to underestimate TC values. Among the tested methods, Johnstone had the best overall result, with an average error of 25%, well far from the second, Dooge, with 43% of average error. The best results were obtained in only one basin, Dilúvio, the largest one, with an area of 25km², with an error of just 3% for Modified Kirpich, and

  13. Estimation Accuracy on Execution Time of Run-Time Tasks in a Heterogeneous Distributed Environment.

    PubMed

    Liu, Qi; Cai, Weidong; Jin, Dandan; Shen, Jian; Fu, Zhangjie; Liu, Xiaodong; Linge, Nigel

    2016-01-01

    Distributed Computing has achieved tremendous development since cloud computing was proposed in 2006, and played a vital role promoting rapid growth of data collecting and analysis models, e.g., Internet of things, Cyber-Physical Systems, Big Data Analytics, etc. Hadoop has become a data convergence platform for sensor networks. As one of the core components, MapReduce facilitates allocating, processing and mining of collected large-scale data, where speculative execution strategies help solve straggler problems. However, there is still no efficient solution for accurate estimation on execution time of run-time tasks, which can affect task allocation and distribution in MapReduce. In this paper, task execution data have been collected and employed for the estimation. A two-phase regression (TPR) method is proposed to predict the finishing time of each task accurately. Detailed data of each task have drawn interests with detailed analysis report being made. According to the results, the prediction accuracy of concurrent tasks' execution time can be improved, in particular for some regular jobs. PMID:27589753

  14. Estimation Accuracy on Execution Time of Run-Time Tasks in a Heterogeneous Distributed Environment.

    PubMed

    Liu, Qi; Cai, Weidong; Jin, Dandan; Shen, Jian; Fu, Zhangjie; Liu, Xiaodong; Linge, Nigel

    2016-08-30

    Distributed Computing has achieved tremendous development since cloud computing was proposed in 2006, and played a vital role promoting rapid growth of data collecting and analysis models, e.g., Internet of things, Cyber-Physical Systems, Big Data Analytics, etc. Hadoop has become a data convergence platform for sensor networks. As one of the core components, MapReduce facilitates allocating, processing and mining of collected large-scale data, where speculative execution strategies help solve straggler problems. However, there is still no efficient solution for accurate estimation on execution time of run-time tasks, which can affect task allocation and distribution in MapReduce. In this paper, task execution data have been collected and employed for the estimation. A two-phase regression (TPR) method is proposed to predict the finishing time of each task accurately. Detailed data of each task have drawn interests with detailed analysis report being made. According to the results, the prediction accuracy of concurrent tasks' execution time can be improved, in particular for some regular jobs.

  15. Estimation Accuracy on Execution Time of Run-Time Tasks in a Heterogeneous Distributed Environment

    PubMed Central

    Liu, Qi; Cai, Weidong; Jin, Dandan; Shen, Jian; Fu, Zhangjie; Liu, Xiaodong; Linge, Nigel

    2016-01-01

    Distributed Computing has achieved tremendous development since cloud computing was proposed in 2006, and played a vital role promoting rapid growth of data collecting and analysis models, e.g., Internet of things, Cyber-Physical Systems, Big Data Analytics, etc. Hadoop has become a data convergence platform for sensor networks. As one of the core components, MapReduce facilitates allocating, processing and mining of collected large-scale data, where speculative execution strategies help solve straggler problems. However, there is still no efficient solution for accurate estimation on execution time of run-time tasks, which can affect task allocation and distribution in MapReduce. In this paper, task execution data have been collected and employed for the estimation. A two-phase regression (TPR) method is proposed to predict the finishing time of each task accurately. Detailed data of each task have drawn interests with detailed analysis report being made. According to the results, the prediction accuracy of concurrent tasks’ execution time can be improved, in particular for some regular jobs. PMID:27589753

  16. Stimulus probability effects in absolute identification.

    PubMed

    Kent, Christopher; Lamberts, Koen

    2016-05-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of presentation probability on both proportion correct and response times. The effects were moderated by the ubiquitous stimulus position effect. The accuracy and response time data were predicted by an exemplar-based model of perceptual cognition (Kent & Lamberts, 2005). The bow in discriminability was also attenuated when presentation probability for middle items was relatively high, an effect that will constrain future model development. The study provides evidence for item-specific learning in absolute identification. Implications for other theories of absolute identification are discussed. (PsycINFO Database Record

  17. Cued Speech Transliteration: Effects of Speaking Rate and Lag Time on Production Accuracy.

    PubMed

    Krause, Jean C; Tessler, Morgan P

    2016-10-01

    Many deaf and hard-of-hearing children rely on interpreters to access classroom communication. Although the exact level of access provided by interpreters in these settings is unknown, it is likely to depend heavily on interpreter accuracy (portion of message correctly produced by the interpreter) and the factors that govern interpreter accuracy. In this study, the accuracy of 12 Cued Speech (CS) transliterators with varying degrees of experience was examined at three different speaking rates (slow, normal, fast). Accuracy was measured with a high-resolution, objective metric in order to facilitate quantitative analyses of the effect of each factor on accuracy. Results showed that speaking rate had a large negative effect on accuracy, caused primarily by an increase in omitted cues, whereas the effect of lag time on accuracy, also negative, was quite small and explained just 3% of the variance. Increased experience level was generally associated with increased accuracy; however, high levels of experience did not guarantee high levels of accuracy. Finally, the overall accuracy of the 12 transliterators, 54% on average across all three factors, was low enough to raise serious concerns about the quality of CS transliteration services that (at least some) children receive in educational settings. PMID:27221370

  18. Accuracy, security, and processing time comparisons of biometric fingerprint recognition system using digital and optical enhancements

    NASA Astrophysics Data System (ADS)

    Alsharif, Salim; El-Saba, Aed; Jagapathi, Rajendarreddy

    2011-06-01

    Fingerprint recognition is one of the most commonly used forms of biometrics and has been widely used in daily life due to its feasibility, distinctiveness, permanence, accuracy, reliability, and acceptability. Besides cost, issues related to accuracy, security, and processing time in practical biometric recognition systems represent the most critical factors that makes these systems widely acceptable. Accurate and secure biometric systems often require sophisticated enhancement and encoding techniques that burdens the overall processing time of the system. In this paper we present a comparison between common digital and optical enhancementencoding techniques with respect to their accuracy, security and processing time, when applied to biometric fingerprint systems.

  19. Stimulus Probability Effects in Absolute Identification

    ERIC Educational Resources Information Center

    Kent, Christopher; Lamberts, Koen

    2016-01-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of…

  20. Absolute nuclear material assay

    DOEpatents

    Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.

    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.

  1. Absolute nuclear material assay

    DOEpatents

    Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.

    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.

  2. Measures of spatio-temporal accuracy for time series land cover data

    NASA Astrophysics Data System (ADS)

    Tsutsumida, Narumasa; Comber, Alexis J.

    2015-09-01

    Remote sensing is a useful tool for monitoring changes in land cover over time. The accuracy of such time-series analyses has hitherto only been assessed using confusion matrices. The matrix allows global measures of user, producer and overall accuracies to be generated, but lacks consideration of any spatial aspects of accuracy. It is well known that land cover errors are typically spatially auto-correlated and can have a distinct spatial distribution. As yet little work has considered the temporal dimension and investigated the persistence or errors in both geographic and temporal dimensions. Spatio-temporal errors can have a profound impact on both change detection and on environmental monitoring and modelling activities using land cover data. This study investigated methods for describing the spatio-temporal characteristics of classification accuracy. Annual thematic maps were created using a random forest classification of MODIS data over the Jakarta metropolitan areas for the period of 2001-2013. A logistic geographically weighted model was used to estimate annual spatial measures of user, producer and overall accuracies. A principal component analysis was then used to extract summaries of the multi-temporal accuracy. The results showed how the spatial distribution of user and producer accuracy varied over space and time, and overall spatial variance was confirmed by the principal component analysis. The results indicated that areas of homogeneous land cover were mapped with relatively high accuracy and low variability, and areas of mixed land cover with the opposite characteristics. A multi-temporal spatial approach to accuracy is shown to provide more informative measures of accuracy, allowing map producers and users to evaluate time series thematic maps more comprehensively than a standard confusion matrix approach. The need to identify suitable properties for a temporal kernel are discussed.

  3. A Systematic Investigation of Accuracy and Response Time Based Measures Used to Index ANS Acuity

    PubMed Central

    Dietrich, Julia Felicitas; Huber, Stefan; Klein, Elise; Willmes, Klaus; Pixner, Silvia; Moeller, Korbinian

    2016-01-01

    The approximate number system (ANS) was proposed to be a building block for later mathematical abilities. Several measures have been used interchangeably to assess ANS acuity. Some of these measures were based on accuracy data, whereas others relied on response time (RT) data or combined accuracy and RT data. Previous studies challenged the view that all these measures can be used interchangeably, because low correlations between some of the measures had been observed. These low correlations might be due to poor reliability of some of the measures, since the majority of these measures are mathematically related. Here we systematically investigated the relationship between common ANS measures while avoiding the potential confound of poor reliability. Our first experiment revealed high correlations between all accuracy based measures supporting the assumption that all of them can be used interchangeably. In contrast, not all RT based measures were highly correlated. Additionally, our results revealed a speed-accuracy trade-off. Thus, accuracy and RT based measures provided conflicting conclusions regarding ANS acuity. Therefore, we investigated in two further experiments which type of measure (accuracy or RT) is more informative about the underlying ANS acuity, depending on participants’ preferences for accuracy or speed. To this end, we manipulated participants’ preferences for accuracy or speed both explicitly using different task instructions and implicitly varying presentation duration. Accuracy based measures were more informative about the underlying ANS acuity than RT based measures. Moreover, the influence of the underlying representations on accuracy data was more pronounced when participants preferred accuracy over speed after the accuracy instruction as well as for long or unlimited presentation durations. Implications regarding the diffusion model as a theoretical framework of dot comparison as well as regarding the relationship between ANS acuity and

  4. A Systematic Investigation of Accuracy and Response Time Based Measures Used to Index ANS Acuity.

    PubMed

    Dietrich, Julia Felicitas; Huber, Stefan; Klein, Elise; Willmes, Klaus; Pixner, Silvia; Moeller, Korbinian

    2016-01-01

    The approximate number system (ANS) was proposed to be a building block for later mathematical abilities. Several measures have been used interchangeably to assess ANS acuity. Some of these measures were based on accuracy data, whereas others relied on response time (RT) data or combined accuracy and RT data. Previous studies challenged the view that all these measures can be used interchangeably, because low correlations between some of the measures had been observed. These low correlations might be due to poor reliability of some of the measures, since the majority of these measures are mathematically related. Here we systematically investigated the relationship between common ANS measures while avoiding the potential confound of poor reliability. Our first experiment revealed high correlations between all accuracy based measures supporting the assumption that all of them can be used interchangeably. In contrast, not all RT based measures were highly correlated. Additionally, our results revealed a speed-accuracy trade-off. Thus, accuracy and RT based measures provided conflicting conclusions regarding ANS acuity. Therefore, we investigated in two further experiments which type of measure (accuracy or RT) is more informative about the underlying ANS acuity, depending on participants' preferences for accuracy or speed. To this end, we manipulated participants' preferences for accuracy or speed both explicitly using different task instructions and implicitly varying presentation duration. Accuracy based measures were more informative about the underlying ANS acuity than RT based measures. Moreover, the influence of the underlying representations on accuracy data was more pronounced when participants preferred accuracy over speed after the accuracy instruction as well as for long or unlimited presentation durations. Implications regarding the diffusion model as a theoretical framework of dot comparison as well as regarding the relationship between ANS acuity and

  5. Improved Motor-Timing: Effects of Synchronized Metro-Nome Training on Golf Shot Accuracy

    PubMed Central

    Sommer, Marius; Rönnqvist, Louise

    2009-01-01

    This study investigates the effect of synchronized metronome training (SMT) on motor timing and how this training might affect golf shot accuracy. Twenty-six experienced male golfers participated (mean age 27 years; mean golf handicap 12.6) in this study. Pre- and post-test investigations of golf shots made by three different clubs were conducted by use of a golf simulator. The golfers were randomized into two groups: a SMT group and a Control group. After the pre-test, the golfers in the SMT group completed a 4-week SMT program designed to improve their motor timing, the golfers in the Control group were merely training their golf-swings during the same time period. No differences between the two groups were found from the pre-test outcomes, either for motor timing scores or for golf shot accuracy. However, the post-test results after the 4-weeks SMT showed evident motor timing improvements. Additionally, significant improvements for golf shot accuracy were found for the SMT group and with less variability in their performance. No such improvements were found for the golfers in the Control group. As with previous studies that used a SMT program, this study’s results provide further evidence that motor timing can be improved by SMT and that such timing improvement also improves golf accuracy. Key points This study investigates the effect of synchronized metronome training (SMT) on motor timing and how this training might affect golf shot accuracy. A randomized control group design was used. The 4 week SMT intervention showed significant improvements in motor timing, golf shot accuracy, and lead to less variability. We conclude that this study’s results provide further evidence that motor timing can be improved by SMT training and that such timing improvement also improves golf accuracy. PMID:24149608

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

    DOEpatents

    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.

  7. Effects of knowledge of results (KR) frequency in the learning of a timing skill: absolute versus relative KR frequency.

    PubMed

    Vieira, Márcio M; Ugrinowitsch, Herbert; Oliveira, Fernanda S; Gallo, Lívia G; Benda, Rodolfo N

    2012-10-01

    The interaction between the amount of practice and frequency of Knowledge of Results (KR) was investigated in a timing skill. In the acquisition phase the task involved 90 trials of releasing a knob and transporting three tennis balls from three near recipients to three far ones in a specific sequence and target time. The retention test performed 24 hr. later had the same sequence of transport but a new target time was required. In both phases, absolute error and standard deviation plus constant error was measured. The five groups differed in relation to frequency of KR and amount of practice. The results showed that intermediate frequencies as well as higher frequencies of KR elicited better performance during the retention test. PMID:23265002

  8. Effects of knowledge of results (KR) frequency in the learning of a timing skill: absolute versus relative KR frequency.

    PubMed

    Vieira, Márcio M; Ugrinowitsch, Herbert; Oliveira, Fernanda S; Gallo, Lívia G; Benda, Rodolfo N

    2012-10-01

    The interaction between the amount of practice and frequency of Knowledge of Results (KR) was investigated in a timing skill. In the acquisition phase the task involved 90 trials of releasing a knob and transporting three tennis balls from three near recipients to three far ones in a specific sequence and target time. The retention test performed 24 hr. later had the same sequence of transport but a new target time was required. In both phases, absolute error and standard deviation plus constant error was measured. The five groups differed in relation to frequency of KR and amount of practice. The results showed that intermediate frequencies as well as higher frequencies of KR elicited better performance during the retention test.

  9. Prism-pair interferometry by homodyne interferometers with a common light source for high-accuracy measurement of the absolute refractive index of glasses

    SciTech Connect

    Hori, Yasuaki; Hirai, Akiko; Minoshima, Kaoru

    2011-03-10

    A prism-pair interferometer comprising two homodyne interferometers with a common light source was developed for high-precision measurements of the refractive index of optical glasses with an uncertainty of the order of 10{sup -6}. The two interferometers measure changes in the optical path length in the glass sample and in air, respectively. Uncertainties in the absolute wavelength of the common light source are cancelled out by calculating a ratio between the results from the interferometers. Uncertainties in phase measurement are suppressed by a quadrature detection system. The combined standard uncertainty of the developed system is evaluated as 1.1x10{sup -6}.

  10. Absolute perfusion measurements and associated iodinated contrast agent time course in brain metastasis: a study for contrast-enhanced radiotherapy.

    PubMed

    Obeid, Layal; Deman, Pierre; Tessier, Alexandre; Balosso, Jacques; Estève, François; Adam, Jean-François

    2014-04-01

    Contrast-enhanced radiotherapy is an innovative treatment that combines the selective accumulation of heavy elements in tumors with stereotactic irradiations using medium energy X-rays. The radiation dose enhancement depends on the absolute amount of iodine reached in the tumor and its time course. Quantitative, postinfusion iodine biodistribution and associated brain perfusion parameters were studied in human brain metastasis as key parameters for treatment feasibility and quality. Twelve patients received an intravenous bolus of iodinated contrast agent (CA) (40 mL, 4 mL/s), followed by a steady-state infusion (160 mL, 0.5 mL/s) to ensure stable intratumoral amounts of iodine during the treatment. Absolute iodine concentrations and quantitative perfusion maps were derived from 40 multislice dynamic computed tomography (CT) images of the brain. The postinfusion mean intratumoral iodine concentration (over 30 minutes) reached 1.94 ± 0.12 mg/mL. Reasonable correlations were obtained between these concentrations and the permeability surface area product and the cerebral blood volume. To our knowledge, this is the first quantitative study of CA biodistribution versus time in brain metastasis. The study shows that suitable and stable amounts of iodine can be reached for contrast-enhanced radiotherapy. Moreover, the associated perfusion measurements provide useful information for the patient recruitment and management processes.

  11. A novel double-focusing time-of-flight mass spectrometer for absolute recoil ion cross sections measurements.

    PubMed

    Sigaud, L; de Jesus, V L B; Ferreira, Natalia; Montenegro, E C

    2016-08-01

    In this work, the inclusion of an Einzel-like lens inside the time-of-flight drift tube of a standard mass spectrometer coupled to a gas cell-to study ionization of atoms and molecules by electron impact-is described. Both this lens and a conical collimator are responsible for further focalization of the ions and charged molecular fragments inside the spectrometer, allowing a much better resolution at the time-of-flight spectra, leading to a separation of a single mass-to-charge unit up to 100 a.m.u. The procedure to obtain the overall absolute efficiency of the spectrometer and micro-channel plate detector is also discussed. PMID:27587105

  12. A novel double-focusing time-of-flight mass spectrometer for absolute recoil ion cross sections measurements.

    PubMed

    Sigaud, L; de Jesus, V L B; Ferreira, Natalia; Montenegro, E C

    2016-08-01

    In this work, the inclusion of an Einzel-like lens inside the time-of-flight drift tube of a standard mass spectrometer coupled to a gas cell-to study ionization of atoms and molecules by electron impact-is described. Both this lens and a conical collimator are responsible for further focalization of the ions and charged molecular fragments inside the spectrometer, allowing a much better resolution at the time-of-flight spectra, leading to a separation of a single mass-to-charge unit up to 100 a.m.u. The procedure to obtain the overall absolute efficiency of the spectrometer and micro-channel plate detector is also discussed.

  13. A novel double-focusing time-of-flight mass spectrometer for absolute recoil ion cross sections measurements

    NASA Astrophysics Data System (ADS)

    Sigaud, L.; de Jesus, V. L. B.; Ferreira, Natalia; Montenegro, E. C.

    2016-08-01

    In this work, the inclusion of an Einzel-like lens inside the time-of-flight drift tube of a standard mass spectrometer coupled to a gas cell—to study ionization of atoms and molecules by electron impact—is described. Both this lens and a conical collimator are responsible for further focalization of the ions and charged molecular fragments inside the spectrometer, allowing a much better resolution at the time-of-flight spectra, leading to a separation of a single mass-to-charge unit up to 100 a.m.u. The procedure to obtain the overall absolute efficiency of the spectrometer and micro-channel plate detector is also discussed.

  14. Accuracy and computational efficiency of real-time subspace propagation schemes for the time-dependent density functional theory

    NASA Astrophysics Data System (ADS)

    Russakoff, Arthur; Li, Yonghui; He, Shenglai; Varga, Kalman

    2016-05-01

    Time-dependent Density Functional Theory (TDDFT) has become successful for its balance of economy and accuracy. However, the application of TDDFT to large systems or long time scales remains computationally prohibitively expensive. In this paper, we investigate the numerical stability and accuracy of two subspace propagation methods to solve the time-dependent Kohn-Sham equations with finite and periodic boundary conditions. The bases considered are the Lánczos basis and the adiabatic eigenbasis. The results are compared to a benchmark fourth-order Taylor expansion of the time propagator. Our results show that it is possible to use larger time steps with the subspace methods, leading to computational speedups by a factor of 2-3 over Taylor propagation. Accuracy is found to be maintained for certain energy regimes and small time scales.

  15. ABSOLUTE TIMING OF THE CRAB PULSAR WITH THE INTEGRAL/SPI TELESCOPE

    SciTech Connect

    Molkov, S.; Jourdain, E.; Roques, J. P.

    2010-01-01

    We have investigated the pulse shape evolution of the Crab pulsar emission in the hard X-ray domain of the electromagnetic spectrum. In particular, we have studied the alignment of the Crab pulsar phase profiles measured in the hard X-rays and in other wavebands. To obtain the hard X-ray pulse profiles, we have used six years (2003-2009, with a total exposure of about 4 Ms) of publicly available data of the SPI telescope on-board the International Gamma-Ray Astrophysics Laboratory observatory, folded with the pulsar time solution derived from the Jodrell Bank Crab Pulsar Monthly Ephemeris. We found that the main pulse in the hard X-ray 20-100 keV energy band leads the radio one by 8.18 +- 0.46 milliperiods in phase, or 275 +- 15 mus in time. Quoted errors represent only statistical uncertainties. Our systematic error is estimated to be approx40 mus and is mainly caused by the radio measurement uncertainties. In hard X-rays, the average distance between the main pulse and interpulse on the phase plane is 0.3989 +- 0.0009. To compare our findings in hard X-rays with the soft 2-20 keV X-ray band, we have used data of quasi-simultaneous Crab observations with the proportional counter array monitor on-board the Rossi X-Ray Timing Explorer mission. The time lag and the pulses separation values measured in the 3-20 keV band are 0.00933 +- 0.00016 (corresponding to 310 +- 6 mus) and 0.40016 +- 0.00028 parts of the cycle, respectively. While the pulse separation values measured in soft X-rays and hard X-rays agree, the time lags are statistically different. Additional analysis show that the delay between the radio and X-ray signals varies with energy in the 2-300 keV energy range. We explain such a behavior as due to the superposition of two independent components responsible for the Crab pulsed emission in this energy band.

  16. Neither One-Time Negative Screening Tests nor Negative Colposcopy Provides Absolute Reassurance against Cervical Cancer

    PubMed Central

    Castle, Philip E.; Rodríguez, Ana C.; Burk, Robert D.; Herrero, Rolando; Hildesheim, Allan; Solomon, Diane; Sherman, Mark E.; Jeronimo, Jose; Alfaro, Mario; Morales, Jorge; Guillén, Diego; Hutchinson, Martha L.; Wacholder, Sholom; Schiffman, Mark

    2009-01-01

    A population sample of 10,049 women living in Guanacaste, Costa Rica was recruited into a natural history of human papillomavirus (HPV) and cervical neoplasia study in 1993–4. At the enrollment visit, we applied multiple state-of-the-art cervical cancer screening methods to detect prevalent cervical cancer and to prevent subsequent cervical cancers by the timely detection and treatment of precancerous lesions. Women were screened at enrollment with 3 kinds of cytology (often reviewed by more than one pathologist), visual inspection, and Cervicography. Any positive screening test led to colposcopic referral and biopsy and/or excisional treatment of CIN2 or worse. We retrospectively tested stored specimens with an early HPV test (Hybrid Capture Tube Test) and for >40 HPV genotypes using a research PCR assay. We followed women typically 5–7 years and some up to 11 years. Nonetheless, sixteen cases of invasive cervical cancer were diagnosed during follow-up. Six cancer cases were failures at enrollment to detect abnormalities by cytology screening; three of the six were also negative at enrollment by sensitive HPV DNA testing. Seven cancers represent failures of colposcopy to diagnose cancer or a precancerous lesion in screen-positive women. Finally, three cases arose despite attempted excisional treatment of precancerous lesions. Based on this evidence, we suggest that no current secondary cervical cancer prevention technologies applied once in a previously under-screened population is likely to be 100% efficacious in preventing incident diagnoses of invasive cervical cancer. PMID:19569231

  17. Absolute rate constant determinations for the deactivation of O/1D/ by time resolved decay of O/1D/ yields O/3P/ emission

    NASA Technical Reports Server (NTRS)

    Davidson, J. A.; Sadowski, C. M.; Schiff, H. I.; Howard, C. J.; Schmeltekopf, A. L.; Jennings, D. A.; Streit, G. E.

    1976-01-01

    Absolute rate constants for the deactivation of O(1D) atoms by some atmospheric gases have been determined by observing the time-resolved emission of O(1D) at 630 nm. O(1D) atoms were produced by the dissociation of ozone via repetitive laser pulses at 266 nm. Absolute rate constants for the relaxation of O(1D) at 298 K are reported for N2, O2, CO2, O3, H2, D2, CH4, HCl, NH3, H2O, N2O, and Ne. The results obtained are compared with previous relative and absolute measurements reported in the literature.

  18. An effective timing characterization method for an accuracy-proved VLSI standard cell library

    NASA Astrophysics Data System (ADS)

    Jianhua, Jiang; Man, Liang; Lei, Wang; Yumei, Zhou

    2014-02-01

    This paper presents a method of tailoring the characterization and modeling timing of a VLSI standard cell library. The paper also presents a method to validate the reasonability of the value through accuracy analysis. In the process of designing a standard cell library, this method is applied to characterize the cell library. In addition, the error calculations of some simple circuit path delays are compared between using the characterization file and an Hspice simulation. The comparison results demonstrate the accuracy of the generated timing library file.

  19. Leptin in whales: validation and measurement of mRNA expression by absolute quantitative real-time PCR.

    PubMed

    Ball, Hope C; Holmes, Robert K; Londraville, Richard L; Thewissen, Johannes G M; Duff, Robert Joel

    2013-01-01

    Leptin is the primary hormone in mammals that regulates adipose stores. Arctic adapted cetaceans maintain enormous adipose depots, suggesting possible modifications of leptin or receptor function. Determining expression of these genes is the first step to understanding the extreme physiology of these animals, and the uniqueness of these animals presents special challenges in estimating and comparing expression levels of mRNA transcripts. Here, we compare expression of two model genes, leptin and leptin-receptor gene-related product (OB-RGRP), using two quantitative real-time PCR (qPCR) methods: "relative" and "absolute". To assess the expression of leptin and OB-RGRP in cetacean tissues, we first examined how relative expression of those genes might differ when normalized to four common endogenous control genes. We performed relative expression qPCR assays measuring the amplification of these two model target genes relative to amplification of 18S ribosomal RNA (18S), ubiquitously expressed transcript (Uxt), ribosomal protein 9 (Rs9) and ribosomal protein 15 (Rs15) endogenous controls. Results demonstrated significant differences in the expression of both genes when different control genes were employed; emphasizing a limitation of relative qPCR assays, especially in studies where differences in physiology and/or a lack of knowledge regarding levels and patterns of expression of common control genes may possibly affect data interpretation. To validate the absolute quantitative qPCR methods, we evaluated the effects of plasmid structure, the purity of the plasmid standard preparation and the influence of type of qPCR "background" material on qPCR amplification efficiencies and copy number determination of both model genes, in multiple tissues from one male bowhead whale. Results indicate that linear plasmids are more reliable than circular plasmid standards, no significant differences in copy number estimation based upon background material used, and that the use of

  20. Absolute accuracy and sensitivity analysis of OP-FTIR retrievals of CO2, CH4 and CO over concentrations representative of "clean air" and "polluted plumes"

    NASA Astrophysics Data System (ADS)

    Smith, T. E. L.; Wooster, M. J.; Tattaris, M.; Griffith, D. W. T.

    2011-01-01

    When compared to established point-sampling methods, Open-Path Fourier Transform Infrared (OP-FTIR) spectroscopy can provide path-integrated concentrations of multiple gases simultaneously, in situ and near-continuously. The trace gas pathlength amounts can be retrieved from the measured IR spectra using a forward model coupled to a non-linear least squares fitting procedure, without requiring "background" spectral measurements unaffected by the gases of interest. However, few studies have investigated the accuracy of such retrievals for CO2, CH4 and CO, particularly across broad concentration ranges covering those characteristic of ambient to highly polluted air (e.g. from biomass burning or industrial plumes). Here we perform such an assessment using data collected by a field-portable FTIR spectrometer. The FTIR was positioned to view a fixed IR source placed at the other end of an IR-transparent cell filled with the gases of interest, whose target concentrations were varied by more than two orders of magnitude. Retrievals made using the model are complicated by absorption line pressure broadening, the effects of temperature on absorption band shape, and by convolution of the gas absorption lines and the instrument line shape (ILS). Despite this, with careful model parameterisation (i.e. the optimum wavenumber range, ILS, and assumed gas temperature and pressure for the retrieval), concentrations for all target gases were able to be retrieved to within 5%. Sensitivity to the aforementioned model inputs was also investigated. CO retrievals were shown to be most sensitive to the ILS (a function of the assumed instrument field-of-view), which is due to the narrow nature of CO absorption lines and their consequent sensitivity to convolution with the ILS. Conversely, CO2 retrievals were most sensitive to assumed atmospheric parameters, particularly gas temperature. Our findings provide confidence that FTIR-derived trace gas retrievals of CO2, CH4 and CO based on

  1. The Effect of Intervention on Accuracy of Students' Responses and Reaction Times to Geometry Problems

    ERIC Educational Resources Information Center

    Babai, Reuven; Zilber, Hanna; Stavy, Ruth; Tirosh, Dina

    2010-01-01

    This study investigates the effect on student performance in drawing their attention to relevant task variables, focusing on accuracy of responses and reaction times. We chose this methodology in order to better understand how such interventions affect the reasoning process. The study employs a geometry task in which the irrelevant salient…

  2. An Accuracy--Response Time Capacity Assessment Function that Measures Performance against Standard Parallel Predictions

    ERIC Educational Resources Information Center

    Townsend, James T.; Altieri, Nicholas

    2012-01-01

    Measures of human efficiency under increases in mental workload or attentional limitations are vital in studying human perception, cognition, and action. Assays of efficiency as workload changes have typically been confined to either reaction times (RTs) or accuracy alone. Within the realm of RTs, a nonparametric measure called the "workload…

  3. Beyond Test Accuracy: Benefits of Measuring Response Time in Computerised Testing

    ERIC Educational Resources Information Center

    Gvozdenko, Eugene; Chambers, Dianne

    2007-01-01

    This paper investigates how monitoring the time spent on a question in a test of basic mathematics skills can provide insights into learning processes, the quality of test takers' knowledge, and cognitive demands and performance of test items that otherwise would remain undiscovered if the usual test outcome of accuracy only format…

  4. Studies of the accuracy of time integration methods for reaction-diffusion equations

    NASA Astrophysics Data System (ADS)

    Ropp, David L.; Shadid, John N.; Ober, Curtis C.

    2004-03-01

    In this study we present numerical experiments of time integration methods applied to systems of reaction-diffusion equations. Our main interest is in evaluating the relative accuracy and asymptotic order of accuracy of the methods on problems which exhibit an approximate balance between the competing component time scales. Nearly balanced systems can produce a significant coupling of the physical mechanisms and introduce a slow dynamical time scale of interest. These problems provide a challenging test for this evaluation and tend to reveal subtle differences between the various methods. The methods we consider include first- and second-order semi-implicit, fully implicit, and operator-splitting techniques. The test problems include a prototype propagating nonlinear reaction-diffusion wave, a non-equilibrium radiation-diffusion system, a Brusselator chemical dynamics system and a blow-up example. In this evaluation we demonstrate a "split personality" for the operator-splitting methods that we consider. While operator-splitting methods often obtain very good accuracy, they can also manifest a serious degradation in accuracy due to stability problems.

  5. Determining Stroke Onset Time Using Quantitative MRI: High Accuracy, Sensitivity and Specificity Obtained from Magnetic Resonance Relaxation Times

    PubMed Central

    McGarry, Bryony L.; Rogers, Harriet J.; Knight, Michael J.; Jokivarsi, Kimmo T.; Gröhn, Olli H.J.; Kauppinen, Risto A.

    2016-01-01

    Many ischaemic stroke patients are ineligible for thrombolytic therapy due to unknown onset time. Quantitative MRI (qMRI) is a potential surrogate for stroke timing. Rats were subjected to permanent middle cerebral artery occlusion and qMRI parameters including hemispheric differences in apparent diffusion coefficient, T2-weighted signal intensities, T1 and T2 relaxation times (qT1, qT2) and f1, f2 and Voverlap were measured at hourly intervals at 4.7 or 9.4 T. Accuracy and sensitivity for identifying strokes scanned within and beyond 3 h of onset was determined. Accuracy for Voverlap, f2 and qT2 (>90%) was significantly higher than other parameters. At a specificity of 1, sensitivity was highest for Voverlap (0.90) and f2 (0.80), indicating promise of these qMRI indices in the clinical assessment of stroke onset time.

  6. Absolute accuracy and sensitivity analysis of OP-FTIR retrievals of CO2, CH4 and CO over concentrations representative of ''clean air'' and ''polluted plumes''

    NASA Astrophysics Data System (ADS)

    Smith, T. E. L.; Wooster, M. J.; Tattaris, M.; Griffith, D. W. T.

    2010-08-01

    When compared to established point-sampling methods, Open-Path Fourier Transform Infrared (OP-FTIR) spectroscopy can provide path-integrated concentrations of multiple gases simultaneously, in situ and near-continuously. Concentrations can be retrieved from the measured IR spectra using a forward model coupled to a non-linear least squares fitting procedure, without requiring ''background'' spectral measurements unaffected by the gases of interest. However, few studies have investigated the accuracy of such retrievals for CO2, CH4 and CO, particularly across a broad concentration range covering ambient to highly polluted air (e.g. from biomass burning or industrial plumes). Here we perform such an assessment using data collected by a field-portable FTIR spectrometer. The FTIR was positioned to view a fixed IR source placed at the other end of an IR-transparent cell filled with the gases of interest, whose target concentrations were varied by up to two orders of magnitude. Retrievals made using the forward model are complicated by absorption line pressure broadening, the effects of temperature on absorption band shape and by convolution of the gas absorption lines and the instrument line shape (ILS). Despite this, with optimal forward model parameterisation (i.e. the wavenumber range used in the retrieval, gas temperature, pressure and ILS), concentration retrievals for all gases were able to be made to within 5% of the true value. Sensitivity to the aforementioned model inputs was also investigated. CO retrievals were shown to be most sensitive to the ILS (a function of the assumed instrument FOV), which is due to the narrow nature of CO absorption lines and their consequent sensitivity to convolution with the ILS. Conversely, CO2 retrievals were most sensitive to assumed atmospheric parameters, particularly temperature. The analysis suggests that trace gas concentration retrieval errors can remain well below 10%, even with the uncertainties in atmospheric pressure

  7. Detection and absolute quantitation of Tomato torrado virus (ToTV) by real time RT-PCR.

    PubMed

    Herrera-Vásquez, José Angel; Rubio, Luis; Alfaro-Fernández, Ana; Debreczeni, Diana Elvira; Font-San-Ambrosio, Isabel; Falk, Bryce W; Ferriol, Inmaculada

    2015-09-01

    Tomato torrado virus (ToTV) causes serious damage to the tomato industry and significant economic losses. A quantitative real-time reverse-transcription polymerase chain reaction (RT-qPCR) method using primers and a specific TaqMan(®) MGB probe for ToTV was developed for sensitive detection and quantitation of different ToTV isolates. A standard curve using RNA transcripts enabled absolute quantitation, with a dynamic range from 10(4) to 10(10) ToTV RNA copies/ng of total RNA. The specificity of the RT-qPCR was tested with twenty-three ToTV isolates from tomato (Solanum lycopersicum L.), and black nightshade (Solanum nigrum L.) collected in Spain, Australia, Hungary and France, which covered the genetic variation range of this virus. This new RT-qPCR assay enables a reproducible, sensitive and specific detection and quantitation of ToTV, which can be a valuable tool in disease management programs and epidemiological studies.

  8. A space system for high-accuracy global time and frequency comparison of clocks

    NASA Technical Reports Server (NTRS)

    Decher, R.; Allan, D. W.; Alley, C. O.; Vessot, R. F. C.; Winkler, G. M. R.

    1981-01-01

    A Space Shuttle experiment in which a hydrogen maser clock on board the Space Shuttle will be compared with clocks on the ground using two-way microwave and short pulse laser signals is described. The accuracy goal for the experiment is 1 nsec or better for the time transfer and 10 to the minus 14th power for the frequency comparison. A direct frequency comparison of primary standards at the 10 to the minus 14th power accuracy level is a unique feature of the proposed system. Both time and frequency transfer will be accomplished by microwave transmission, while the laser signals provide calibration of the system as well as subnanosecond time transfer.

  9. An effective approach to improving low-cost GPS positioning accuracy in real-time navigation.

    PubMed

    Islam, Md Rashedul; Kim, Jong-Myon

    2014-01-01

    Positioning accuracy is a challenging issue for location-based applications using a low-cost global positioning system (GPS). This paper presents an effective approach to improving the positioning accuracy of a low-cost GPS receiver for real-time navigation. The proposed method precisely estimates position by combining vehicle movement direction, velocity averaging, and distance between waypoints using coordinate data (latitude, longitude, time, and velocity) of the GPS receiver. The previously estimated precious reference point, coordinate translation, and invalid data check also improve accuracy. In order to evaluate the performance of the proposed method, we conducted an experiment using a GARMIN GPS 19xHVS receiver attached to a car and used Google Maps to plot the processed data. The proposed method achieved improvement of 4-10 meters in several experiments. In addition, we compared the proposed approach with two other state-of-the-art methods: recursive averaging and ARMA interpolation. The experimental results show that the proposed approach outperforms other state-of-the-art methods in terms of positioning accuracy.

  10. Advanced video extensometer for non-contact, real-time, high-accuracy strain measurement.

    PubMed

    Pan, Bing; Tian, Long

    2016-08-22

    We developed an advanced video extensometer for non-contact, real-time, high-accuracy strain measurement in material testing. In the established video extensometer, a "near perfect and ultra-stable" imaging system, combining the idea of active imaging with a high-quality bilateral telecentric lens, is constructed to acquire high-fidelity video images of the test sample surface, which is invariant to ambient lighting changes and small out-of-plane motions occurred between the object surface and image plane. In addition, an efficient and accurate inverse compositional Gauss-Newton algorithm incorporating a temporal initial guess transfer scheme and a high-accuracy interpolation method is employed to achieve real-time, high-accuracy displacement tracking with negligible bias error. Tensile tests of an aluminum sample and a carbon fiber filament sample were performed to demonstrate the efficiency, repeatability and accuracy of the developed advanced video extensometer. The results indicate that longitudinal and transversal strains can be estimated and plotted at a rate of 117 fps and with a maximum strain error less than 30 microstrains. PMID:27557188

  11. An Effective Approach to Improving Low-Cost GPS Positioning Accuracy in Real-Time Navigation

    PubMed Central

    Islam, Md. Rashedul; Kim, Jong-Myon

    2014-01-01

    Positioning accuracy is a challenging issue for location-based applications using a low-cost global positioning system (GPS). This paper presents an effective approach to improving the positioning accuracy of a low-cost GPS receiver for real-time navigation. The proposed method precisely estimates position by combining vehicle movement direction, velocity averaging, and distance between waypoints using coordinate data (latitude, longitude, time, and velocity) of the GPS receiver. The previously estimated precious reference point, coordinate translation, and invalid data check also improve accuracy. In order to evaluate the performance of the proposed method, we conducted an experiment using a GARMIN GPS 19xHVS receiver attached to a car and used Google Maps to plot the processed data. The proposed method achieved improvement of 4–10 meters in several experiments. In addition, we compared the proposed approach with two other state-of-the-art methods: recursive averaging and ARMA interpolation. The experimental results show that the proposed approach outperforms other state-of-the-art methods in terms of positioning accuracy. PMID:25136679

  12. Accuracy of sea level predictions with lead time of one week: a comparison between Prognocean and MyOcean

    NASA Astrophysics Data System (ADS)

    Swierczynska, Malgorzata; Mizinski, Bartlomiej; Niedzielski, Tomasz

    2015-04-01

    There exist several systems which produce sea level forecasts in real time, with lead times ranging from hours to two weeks in the future. One of the recently developed solutions is Prognocean, the system that has been built and implemented at the University of Wroclaw, Poland. Its main feature is that it uses simple time series models to predict sea level anomaly maps, and does it for lead times ranging from 1 to 14 days with daily update. The empirical data-based models are fitted in real time both to individual grids (polynomial-harmonic model, polynomial-harmonic model combined with autoregressive model, polynomial-harmonic model combined with threshold autoregressive model) and to numerous grids forming a spatial latitude x longitude window of 3˚ x 5˚ (polynomial-harmonic model combined with multivariate autoregressive model). Although their simplicity, the approaches have already been shown to produce sea level anomaly predictions of reasonable accuracy. However, none of the analyses targeted at the comparative study which would present the skills of the Prognocean system against a background of the performance of other systems that use physically-based models. This study aims to fill this gap by comparing Prognocean-based predictions for one week into the future with the corresponding prognoses calculated by MyOcean. The reader is provided with the objectively-calculated set of statistics, presented as maps, which describes prediction errors (mean absolute error, root mean square error, index of agreement) and prediction skills (prediction efficiency, coefficient of determination) of the two systems. The exercise enables to compare the skills of the approaches, and the gridwise comparison allows one to identify areas of superior performance of each system.

  13. Accuracy of Pedometer Steps and Time for Youth with Intellectual Disabilities during Dynamic Movements

    ERIC Educational Resources Information Center

    Pitetti, Kenneth H.; Beets, Michael W.; Flaming, Judy

    2009-01-01

    Pedometer accuracy for steps and activity time during dynamic movement for youth with intellectual disabilities (ID) were examined. Twenty-four youth with ID (13 girls, 13.1 [plus or minus] 3.2 yrs; 11 boys, 14.7 [plus or minus] 2.7 yrs) were videotaped during adapted physical education class while wearing a Walk4Life 2505 pedometer in five…

  14. Interpersonal variability in timing strategy and temporal accuracy in rapid interception task with variable time-to-contact.

    PubMed

    Ijiri, Tetsuya; Shinya, Masahiro; Nakazawa, Kimitaka

    2015-01-01

    In rapid interceptive actions such as hitting a baseball, cricket ball or tennis ball, ball speed varies between trials, and players have to compensate the time lag by controlling the moment of movement onset and movement duration. Previous studies have found that these two variables can flexibly co-vary and are robustly influenced by target speed (i.e. velocity-coupling effect: faster movement for faster target). However, some studies reported an interpersonal variability in the timing control strategy and the relationship between the strategy and temporal accuracy in rapid interception is unclear. We used a baseball-simulated rapid interceptive task to assess this issue. Under relatively easy time constraints, there was a large interpersonal variability, and participants were distinctively divided into two groups: those who mainly modulated their movement duration and those who mainly controlled their movement onset. When the time constraint became severe, the second strategy shifted to the first strategy in most of the second group participants. In the both cases, being able to mainly control movement onset resulted in higher temporal accuracy. These results suggest that minimising the velocity-coupling effect is an important factor to achieve high temporal accuracy in rapid interception. PMID:25277080

  15. Interpersonal variability in timing strategy and temporal accuracy in rapid interception task with variable time-to-contact.

    PubMed

    Ijiri, Tetsuya; Shinya, Masahiro; Nakazawa, Kimitaka

    2015-01-01

    In rapid interceptive actions such as hitting a baseball, cricket ball or tennis ball, ball speed varies between trials, and players have to compensate the time lag by controlling the moment of movement onset and movement duration. Previous studies have found that these two variables can flexibly co-vary and are robustly influenced by target speed (i.e. velocity-coupling effect: faster movement for faster target). However, some studies reported an interpersonal variability in the timing control strategy and the relationship between the strategy and temporal accuracy in rapid interception is unclear. We used a baseball-simulated rapid interceptive task to assess this issue. Under relatively easy time constraints, there was a large interpersonal variability, and participants were distinctively divided into two groups: those who mainly modulated their movement duration and those who mainly controlled their movement onset. When the time constraint became severe, the second strategy shifted to the first strategy in most of the second group participants. In the both cases, being able to mainly control movement onset resulted in higher temporal accuracy. These results suggest that minimising the velocity-coupling effect is an important factor to achieve high temporal accuracy in rapid interception.

  16. A phase transition model for the speed-accuracy trade-off in response time experiments.

    PubMed

    Dutilh, Gilles; Wagenmakers, Eric-Jan; Visser, Ingmar; van der Maas, Han L J

    2011-03-01

    Most models of response time (RT) in elementary cognitive tasks implicitly assume that the speed-accuracy trade-off is continuous: When payoffs or instructions gradually increase the level of speed stress, people are assumed to gradually sacrifice response accuracy in exchange for gradual increases in response speed. This trade-off presumably operates over the entire range from accurate but slow responding to fast but chance-level responding (i.e., guessing). In this article, we challenge the assumption of continuity and propose a phase transition model for RTs and accuracy. Analogous to the fast guess model (Ollman, 1966), our model postulates two modes of processing: a guess mode and a stimulus-controlled mode. From catastrophe theory, we derive two important predictions that allow us to test our model against the fast guess model and against the popular class of sequential sampling models. The first prediction--hysteresis in the transitions between guessing and stimulus-controlled behavior--was confirmed in an experiment that gradually changed the reward for speed versus accuracy. The second prediction--bimodal RT distributions--was confirmed in an experiment that required participants to respond in a way that is intermediate between guessing and accurate responding.

  17. Travel-time source-specific station correction improves location accuracy

    NASA Astrophysics Data System (ADS)

    Giuntini, Alessandra; Materni, Valerio; Chiappini, Stefano; Carluccio, Roberto; Console, Rodolfo; Chiappini, Massimo

    2013-04-01

    Accurate earthquake locations are crucial for investigating seismogenic processes, as well as for applications like verifying compliance to the Comprehensive Test Ban Treaty (CTBT). Earthquake location accuracy is related to the degree of knowledge about the 3-D structure of seismic wave velocity in the Earth. It is well known that modeling errors of calculated travel times may have the effect of shifting the computed epicenters far from the real locations by a distance even larger than the size of the statistical error ellipses, regardless of the accuracy in picking seismic phase arrivals. The consequences of large mislocations of seismic events in the context of the CTBT verification is particularly critical in order to trigger a possible On Site Inspection (OSI). In fact, the Treaty establishes that an OSI area cannot be larger than 1000 km2, and its larger linear dimension cannot be larger than 50 km. Moreover, depth accuracy is crucial for the application of the depth event screening criterion. In the present study, we develop a method of source-specific travel times corrections based on a set of well located events recorded by dense national seismic networks in seismically active regions. The applications concern seismic sequences recorded in Japan, Iran and Italy. We show that mislocations of the order of 10-20 km affecting the epicenters, as well as larger mislocations in hypocentral depths, calculated from a global seismic network and using the standard IASPEI91 travel times can be effectively removed by applying source-specific station corrections.

  18. Accuracy and time requirements of a bar-code inventory system for medical supplies.

    PubMed

    Hanson, L B; Weinswig, M H; De Muth, J E

    1988-02-01

    The effects of implementing a bar-code system for issuing medical supplies to nursing units at a university teaching hospital were evaluated. Data on the time required to issue medical supplies to three nursing units at a 480-bed, tertiary-care teaching hospital were collected (1) before the bar-code system was implemented (i.e., when the manual system was in use), (2) one month after implementation, and (3) four months after implementation. At the same times, the accuracy of the central supply perpetual inventory was monitored using 15 selected items. One-way analysis of variance tests were done to determine any significant differences between the bar-code and manual systems. Using the bar-code system took longer than using the manual system because of a significant difference in the time required for order entry into the computer. Multiple-use requirements of the central supply computer system made entering bar-code data a much slower process. There was, however, a significant improvement in the accuracy of the perpetual inventory. Using the bar-code system for issuing medical supplies to the nursing units takes longer than using the manual system. However, the accuracy of the perpetual inventory was significantly improved with the implementation of the bar-code system.

  19. Entropy of space-time outcome in a movement speed-accuracy task.

    PubMed

    Hsieh, Tsung-Yu; Pacheco, Matheus Maia; Newell, Karl M

    2015-12-01

    The experiment reported was set-up to investigate the space-time entropy of movement outcome as a function of a range of spatial (10, 20 and 30 cm) and temporal (250-2500 ms) criteria in a discrete aiming task. The variability and information entropy of the movement spatial and temporal errors considered separately increased and decreased on the respective dimension as a function of an increment of movement velocity. However, the joint space-time entropy was lowest when the relative contribution of spatial and temporal task criteria was comparable (i.e., mid-range of space-time constraints), and it increased with a greater trade-off between spatial or temporal task demands, revealing a U-shaped function across space-time task criteria. The traditional speed-accuracy functions of spatial error and temporal error considered independently mapped to this joint space-time U-shaped entropy function. The trade-off in movement tasks with joint space-time criteria is between spatial error and timing error, rather than movement speed and accuracy.

  20. Presentation and response timing accuracy in Adobe Flash and HTML5/JavaScript Web experiments.

    PubMed

    Reimers, Stian; Stewart, Neil

    2015-06-01

    Web-based research is becoming ubiquitous in the behavioral sciences, facilitated by convenient, readily available participant pools and relatively straightforward ways of running experiments: most recently, through the development of the HTML5 standard. Although in most studies participants give untimed responses, there is a growing interest in being able to record response times online. Existing data on the accuracy and cross-machine variability of online timing measures are limited, and generally they have compared behavioral data gathered on the Web with similar data gathered in the lab. For this article, we took a more direct approach, examining two ways of running experiments online-Adobe Flash and HTML5 with CSS3 and JavaScript-across 19 different computer systems. We used specialist hardware to measure stimulus display durations and to generate precise response times to visual stimuli in order to assess measurement accuracy, examining effects of duration, browser, and system-to-system variability (such as across different Windows versions), as well as effects of processing power and graphics capability. We found that (a) Flash and JavaScript's presentation and response time measurement accuracy are similar; (b) within-system variability is generally small, even in low-powered machines under high load; (c) the variability of measured response times across systems is somewhat larger; and (d) browser type and system hardware appear to have relatively small effects on measured response times. Modeling of the effects of this technical variability suggests that for most within- and between-subjects experiments, Flash and JavaScript can both be used to accurately detect differences in response times across conditions. Concerns are, however, noted about using some correlational or longitudinal designs online.

  1. Presentation and response timing accuracy in Adobe Flash and HTML5/JavaScript Web experiments.

    PubMed

    Reimers, Stian; Stewart, Neil

    2015-06-01

    Web-based research is becoming ubiquitous in the behavioral sciences, facilitated by convenient, readily available participant pools and relatively straightforward ways of running experiments: most recently, through the development of the HTML5 standard. Although in most studies participants give untimed responses, there is a growing interest in being able to record response times online. Existing data on the accuracy and cross-machine variability of online timing measures are limited, and generally they have compared behavioral data gathered on the Web with similar data gathered in the lab. For this article, we took a more direct approach, examining two ways of running experiments online-Adobe Flash and HTML5 with CSS3 and JavaScript-across 19 different computer systems. We used specialist hardware to measure stimulus display durations and to generate precise response times to visual stimuli in order to assess measurement accuracy, examining effects of duration, browser, and system-to-system variability (such as across different Windows versions), as well as effects of processing power and graphics capability. We found that (a) Flash and JavaScript's presentation and response time measurement accuracy are similar; (b) within-system variability is generally small, even in low-powered machines under high load; (c) the variability of measured response times across systems is somewhat larger; and (d) browser type and system hardware appear to have relatively small effects on measured response times. Modeling of the effects of this technical variability suggests that for most within- and between-subjects experiments, Flash and JavaScript can both be used to accurately detect differences in response times across conditions. Concerns are, however, noted about using some correlational or longitudinal designs online. PMID:24903687

  2. Leptin in Whales: Validation and Measurement of mRNA Expression by Absolute Quantitative Real-Time PCR

    PubMed Central

    Ball, Hope C.; Holmes, Robert K.; Londraville, Richard L.; Thewissen, Johannes G. M.; Duff, Robert Joel

    2013-01-01

    Leptin is the primary hormone in mammals that regulates adipose stores. Arctic adapted cetaceans maintain enormous adipose depots, suggesting possible modifications of leptin or receptor function. Determining expression of these genes is the first step to understanding the extreme physiology of these animals, and the uniqueness of these animals presents special challenges in estimating and comparing expression levels of mRNA transcripts. Here, we compare expression of two model genes, leptin and leptin-receptor gene-related product (OB-RGRP), using two quantitative real-time PCR (qPCR) methods: “relative” and “absolute”. To assess the expression of leptin and OB-RGRP in cetacean tissues, we first examined how relative expression of those genes might differ when normalized to four common endogenous control genes. We performed relative expression qPCR assays measuring the amplification of these two model target genes relative to amplification of 18S ribosomal RNA (18S), ubiquitously expressed transcript (Uxt), ribosomal protein 9 (Rs9) and ribosomal protein 15 (Rs15) endogenous controls. Results demonstrated significant differences in the expression of both genes when different control genes were employed; emphasizing a limitation of relative qPCR assays, especially in studies where differences in physiology and/or a lack of knowledge regarding levels and patterns of expression of common control genes may possibly affect data interpretation. To validate the absolute quantitative qPCR methods, we evaluated the effects of plasmid structure, the purity of the plasmid standard preparation and the influence of type of qPCR “background” material on qPCR amplification efficiencies and copy number determination of both model genes, in multiple tissues from one male bowhead whale. Results indicate that linear plasmids are more reliable than circular plasmid standards, no significant differences in copy number estimation based upon background material used, and

  3. Absolute Summ

    NASA Astrophysics Data System (ADS)

    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. .

  4. Trading Speed and Accuracy by Coding Time: A Coupled-circuit Cortical Model

    PubMed Central

    Standage, Dominic; You, Hongzhi; Wang, Da-Hui; Dorris, Michael C.

    2013-01-01

    Our actions take place in space and time, but despite the role of time in decision theory and the growing acknowledgement that the encoding of time is crucial to behaviour, few studies have considered the interactions between neural codes for objects in space and for elapsed time during perceptual decisions. The speed-accuracy trade-off (SAT) provides a window into spatiotemporal interactions. Our hypothesis is that temporal coding determines the rate at which spatial evidence is integrated, controlling the SAT by gain modulation. Here, we propose that local cortical circuits are inherently suited to the relevant spatial and temporal coding. In simulations of an interval estimation task, we use a generic local-circuit model to encode time by ‘climbing’ activity, seen in cortex during tasks with a timing requirement. The model is a network of simulated pyramidal cells and inhibitory interneurons, connected by conductance synapses. A simple learning rule enables the network to quickly produce new interval estimates, which show signature characteristics of estimates by experimental subjects. Analysis of network dynamics formally characterizes this generic, local-circuit timing mechanism. In simulations of a perceptual decision task, we couple two such networks. Network function is determined only by spatial selectivity and NMDA receptor conductance strength; all other parameters are identical. To trade speed and accuracy, the timing network simply learns longer or shorter intervals, driving the rate of downstream decision processing by spatially non-selective input, an established form of gain modulation. Like the timing network's interval estimates, decision times show signature characteristics of those by experimental subjects. Overall, we propose, demonstrate and analyse a generic mechanism for timing, a generic mechanism for modulation of decision processing by temporal codes, and we make predictions for experimental verification. PMID:23592967

  5. Single Particle-Photon Imaging Detector With 4-Dimensional Output: Absolute Time-of-hit, X-Y Position, and PHA: Applications in Space Science Instruments

    NASA Astrophysics Data System (ADS)

    Paschalidis, N. P.; Mitchell, D. G.; Brandt, P. C.

    2006-12-01

    A detector that can simultaneously measure time, position, and pulse high analysis (PHA) of single particle/photons with high resolutions and speeds, is a strong enabling technology for many space science instruments such as: energetic neutral atom imagers, low energy neutrals, energetic particle spectrometers, ion/electron plasma analyzers, UV spectrographs, mass spectrometers, laser range finding imagers, X-ray imagers. This presentation describes one such 4-dimentional detector based on micro-channel plates (MCPs), delay line anodes, and precise time of flight, and charge integration electronics for PHA. More specifically the detector includes: a) An MCP in 2-stack or Z-stack configuration for the particle/photon detection. b) Option for a thin foil or photo-cathode in front of the MCP to increase the detection efficiency of particles or photons respectively. c) Novel 1D or 2D delay line anode adaptable to almost any geometry and physical size of common instruments mentioned above. d) Fast time of flight (TOF) electronics for the absolute time of hit and the X-Y position determination. e) Fast charge integration electronics for PHA of the total charge released by the MCP. Under certain circumstances the PHA gives information about the particle mass such as for protons, He and Oxygen, cross calibrated against UV light which typically gives a single electron distribution. f) FPGA electronics for digital data acquisition and handling. e) Standard mat lab SW for data analysis and visualization in a stand alone application. The detector achieves time of hit accuracy <50ps, X-Y position resolution <20um in a field of 2048 x 2048 pixels (2048 for 1D) and adjustable speeds of: 10MHz at 256 x 256 pixels to 1MHz at 2048 x 2048 pixels. The total-charge analysis is at 10-bits. The detector can be used in its full 4D configuration such as in TOF imaging particle analyzer (i.e ENA), or in a reduced configuration such as in a UV spectrograph with X-Y position only. Typical

  6. A simple method for improving the time-stepping accuracy in atmosphere and ocean models

    NASA Astrophysics Data System (ADS)

    Williams, P. D.

    2012-12-01

    In contemporary numerical simulations of the atmosphere and ocean, evidence suggests that time-stepping errors may be a significant component of total model error, on both weather and climate time-scales. This presentation will review the available evidence, and will then suggest a simple but effective method for substantially improving the time-stepping numerics at no extra computational expense. A common time-stepping method in atmosphere and ocean models is the leapfrog scheme combined with the Robert-Asselin (RA) filter. This method is used in the following models (and many more): ECHAM, MAECHAM, MM5, CAM, MESO-NH, HIRLAM, KMCM, LIMA, SPEEDY, IGCM, PUMA, COSMO, FSU-GSM, FSU-NRSM, NCEP-GFS, NCEP-RSM, NSEAM, NOGAPS, RAMS, and CCSR/NIES-AGCM. Although the RA filter controls the time-splitting instability, it also introduces non-physical damping and reduces the accuracy. This presentation proposes a simple modification to the RA filter, which has become known as the RAW filter (Williams 2009, 2011). When used in conjunction with the leapfrog scheme, the RAW filter eliminates the non-physical damping and increases the amplitude accuracy by two orders, yielding third-order accuracy. (The phase accuracy remains second-order.) The RAW filter can easily be incorporated into existing models, typically via the insertion of just a single line of code. Better simulations are obtained at no extra computational expense. Results will be shown from recent implementations of the RAW filter in various models, including SPEEDY and COSMO. For example, in SPEEDY, the skill of weather forecasts is found to be significantly improved. In particular, in tropical surface pressure predictions, five-day forecasts made using the RAW filter have approximately the same skill as four-day forecasts made using the RA filter (Amezcua, Kalnay & Williams 2011). These improvements are encouraging for the use of the RAW filter in other atmosphere and ocean models. References PD Williams (2009) A

  7. Time lapse imaging of water content with geoelectrical methods: on the interest of working with absolute water content data

    NASA Astrophysics Data System (ADS)

    Dumont, Gaël; Pilawski, Tamara; Robert, Tanguy; Hermans, Thomas; Garré, Sarah; Nguyen, Frederic

    2016-04-01

    The electrical resistivity tomography is a suitable method to estimate the water content of a waste material and detect changes in water content. Various ERT profiles, both static data and time-lapse, where acquired on a landfill during the Minerve project. In the literature, the relative change of resistivity (Δρ/ρ) is generally computed. For saline or heat tracer tests in the saturated zone, the Δρ/ρ can be easily translated into pore water conductivity or underground temperature changes (provided that the initial salinity or temperature condition is homogeneous over the ERT panel extension). For water content changes in the vadose zone resulting of an infiltration event or injection experiment, many authors also work with the Δρ/ρ or relative changes of water content Δθ/θ (linked to the change of resistivity through one single parameter: the Archie's law exponent "m"). This parameter is not influenced by the underground temperature and pore fluid conductivity (ρ¬w) condition but is influenced by the initial water content distribution. Therefore, you never know if the loss of Δθ/θ signal is representative of the limit of the infiltration front or more humid initial condition. Another approach for the understanding of the infiltration process is the assessment of the absolute change of water content (Δθ). This requires the direct computation of the water content of the waste from the resistivity data. For that purpose, we used petrophysical laws calibrated with laboratory experiments and our knowledge of the in situ temperature and pore fluid conductivity parameters. Then, we investigated water content changes in the waste material after a rainfall event (Δθ= Δθ/θ* θ). This new observation is really representatives of the quantity of water infiltrated in the waste material. However, the uncertainty in the pore fluid conductivity value may influence the computed water changes (Δθ=k*m√(ρw) ; where "m" is the Archie's law exponent

  8. Accuracy of the Timed Up and Go test for predicting sarcopenia in elderly hospitalized patients

    PubMed Central

    Martinez, Bruno Prata; Gomes, Isabela Barboza; de Oliveira, Carolina Santana; Ramos, Isis Resende; Rocha, Mônica Diniz Marques; Júnior, Luiz Alberto Forgiarini; Camelier, Fernanda Warken Rosa; Camelier, Aquiles Assunção

    2015-01-01

    OBJECTIVES: The ability of the Timed Up and Go test to predict sarcopenia has not been evaluated previously. The objective of this study was to evaluate the accuracy of the Timed Up and Go test for predicting sarcopenia in elderly hospitalized patients. METHODS: This cross-sectional study analyzed 68 elderly patients (≥60 years of age) in a private hospital in the city of Salvador-BA, Brazil, between the 1st and 5th day of hospitalization. The predictive variable was the Timed Up and Go test score, and the outcome of interest was the presence of sarcopenia (reduced muscle mass associated with a reduction in handgrip strength and/or weak physical performance in a 6-m gait-speed test). After the descriptive data analyses, the sensitivity, specificity and accuracy of a test using the predictive variable to predict the presence of sarcopenia were calculated. RESULTS: In total, 68 elderly individuals, with a mean age 70.4±7.7 years, were evaluated. The subjects had a Charlson Comorbidity Index score of 5.35±1.97. Most (64.7%) of the subjects had a clinical admission profile; the main reasons for hospitalization were cardiovascular disorders (22.1%), pneumonia (19.1%) and abdominal disorders (10.2%). The frequency of sarcopenia in the sample was 22.1%, and the mean length of time spent performing the Timed Up and Go test was 10.02±5.38 s. A time longer than or equal to a cutoff of 10.85 s on the Timed Up and Go test predicted sarcopenia with a sensitivity of 67% and a specificity of 88.7%. The accuracy of this cutoff for the Timed Up and Go test was good (0.80; IC=0.66-0.94; p=0.002). CONCLUSION: The Timed Up and Go test was shown to be a predictor of sarcopenia in elderly hospitalized patients. PMID:26039955

  9. Accuracy of gantry rotation time of less than 300 ms for modern MDCT systems.

    PubMed

    Fukuda, Atsushi; Lin, Pei-Jan Paul; Matsubara, Kosuke; Miyati, Tosiaki

    2015-01-01

    The accuracy of gantry rotation times of less than 300 ms has been assessed for two "state-of-the art" MDCT systems. The rotation time was measured at selected nominal rotation times (275 and 280 ms) with a solid-state detector; Unfors Xi probe. The detector was positioned on the inner bottom of the gantry bore. Because a pair of two successive radiation peaks is necessary for determination of the rotation time, the radiation detection was performed with the helical scan mode of operation. Upon completion of the data acquisition, we determined the peak times with the Unfors Xi View software program to obtain the rotation time. The means and standard deviations of the measured rotation times were 275.3 ± 0.5 and 285.1 ± 0.4 ms, respectively. The inaccuracy of the rotation time was approximately 5 ms at most, which was comparable to that previously reported for slower rotation times.

  10. Improved time efficiency and accuracy in diffusion tensor microimaging with multiple-echo acquisition

    NASA Astrophysics Data System (ADS)

    Gulani, Vikas; Weber, Thomas; Neuberger, Thomas; Webb, Andrew G.

    2005-12-01

    In high-field NMR microscopy rapid single-shot imaging methods, for example, echo planar imaging, cannot be used for determination of the apparent diffusion tensor (ADT) due to large magnetic susceptibility effects. We propose a pulse sequence in which a diffusion-weighted spin-echo is followed by multiple gradient-echoes with additional diffusion weighting. These additional echoes can be used to calculate the ADT and T2∗ maps. We show here that this results in modest but consistent improvements in the accuracy of ADT determination within a given total data acquisition time. The method is tested on excised, chemically fixed rat spinal cords.

  11. Sex differences in accuracy and precision when judging time to arrival: data from two Internet studies.

    PubMed

    Sanders, Geoff; Sinclair, Kamila

    2011-12-01

    We report two Internet studies that investigated sex differences in the accuracy and precision of judging time to arrival. We used accuracy to mean the ability to match the actual time to arrival and precision to mean the consistency with which each participant made their judgments. Our task was presented as a computer game in which a toy UFO moved obliquely towards the participant through a virtual three-dimensional space on route to a docking station. The UFO disappeared before docking and participants pressed their space bar at the precise moment they thought the UFO would have docked. Study 1 showed it was possible to conduct quantitative studies of spatiotemporal judgments in virtual reality via the Internet and confirmed reports that men are more accurate because women underestimate, but found no difference in precision measured as intra-participant variation. Study 2 repeated Study 1 with five additional presentations of one condition to provide a better measure of precision. Again, men were more accurate than women but there were no sex differences in precision. However, within the coincidence-anticipation timing (CAT) literature, of those studies that report sex differences, a majority found that males are both more accurate and more precise than females. Noting that many CAT studies report no sex differences, we discuss appropriate interpretations of such null findings. While acknowledging that CAT performance may be influenced by experience we suggest that the sex difference may have originated among our ancestors with the evolutionary selection of men for hunting and women for gathering.

  12. Comprehensive Numerical Analysis of Finite Difference Time Domain Methods for Improving Optical Waveguide Sensor Accuracy

    PubMed Central

    Samak, M. Mosleh E. Abu; Bakar, A. Ashrif A.; Kashif, Muhammad; Zan, Mohd Saiful Dzulkifly

    2016-01-01

    This paper discusses numerical analysis methods for different geometrical features that have limited interval values for typically used sensor wavelengths. Compared with existing Finite Difference Time Domain (FDTD) methods, the alternating direction implicit (ADI)-FDTD method reduces the number of sub-steps by a factor of two to three, which represents a 33% time savings in each single run. The local one-dimensional (LOD)-FDTD method has similar numerical equation properties, which should be calculated as in the previous method. Generally, a small number of arithmetic processes, which result in a shorter simulation time, are desired. The alternating direction implicit technique can be considered a significant step forward for improving the efficiency of unconditionally stable FDTD schemes. This comparative study shows that the local one-dimensional method had minimum relative error ranges of less than 40% for analytical frequencies above 42.85 GHz, and the same accuracy was generated by both methods.

  13. Absolutely calibrated, time-resolved measurements of soft x rays using transmission grating spectrometers at the Nike Laser Facility

    NASA Astrophysics Data System (ADS)

    Weaver, J. L.; Feldman, U.; Seely, J. F.; Holland, G.; Serlin, V.; Klapisch, M.; Columbant, D.; Mostovych, A.

    2001-12-01

    Accurate simulation of pellet implosions for direct drive inertial confinement fusion requires benchmarking the codes with experimental data. The Naval Research Laboratory (NRL) has begun to measure the absolute intensity of radiation from laser irradiated targets to provide critical information for the radiatively preheated pellet designs developed by the Nike laser group. Two main diagnostics for this effort are two spectrometers incorporating three detection systems. While both spectrometers use 2500 lines/mm transmission gratings, one instrument is coupled to a soft x-ray streak camera and the other is coupled to both an absolutely calibrated Si photodiode array and a charge coupled device (CCD) camera. Absolute calibration of spectrometer components has been undertaken at the National Synchrotron Light Source at Brookhaven National Laboratories. Currently, the system has been used to measure the spatially integrated soft x-ray flux as a function of target material, laser power, and laser spot size. A comparison between measured and calculated flux for Au and CH targets shows reasonable agreement to one-dimensional modeling for two laser power densities.

  14. SU-E-T-346: Validation of Beam Accuracy of a Gated Spot-Scanning Proton Therapy System with Real-Time Tumor-Tracking at Hokkaido University

    SciTech Connect

    Yamada, T; Matsuura, T; Toramatsu, C; Takao, S; Nihongi, H; Miyamoto, N; Shimizu, S; Shirato, H; Takayanagi, T; Umezawa, M; Matsuda, K; Umegaki, K

    2014-06-01

    Purpose: At Hokkaido University, we have developed a gated spot scanning proton beam therapy system with real-time tumor-tracking under collaborative work with Hitachi Ltd. This system has the ability to gate proton beams from the synchrotron, turning the beam on only when the actual positions of inserted fiducial markers monitored by two fluoroscopic X-ray systems are within the planned positions [Shirato, 2012]. In this research, we validated the accuracy of the proton beams while utilizing external gating signals. Methods: The accuracy of spot positions, spot dose, absolute dose at the center of the SOBP, and range were measured while utilizing external gating signals. The following external gating signals were generated by an arbitrary waveform generator: (1) ON at all times (without gating), (2) an OFF period of 4 s followed by an ON period of 1 s, (3) two ON periods of 0.5 s with a 0.15 s OFF interval, (4) signals recorded during the treatment of real-time tumor-tracking X-ray therapy in Hokkaido University. The spot positions and spot dose were measured by beam monitors in the nozzle. The ranges were measured with a multi-layer ion chamber made by Hitachi Ltd. The absolute dose was measured with a Farmer ionization chamber and a RFA300 water phantom system. Results: The maximum error of the beam position in the isocenter plane was 0.8 mm without the gating signal and 1.0 mm with the gating signal. The maximum error of the spot dose was 0.0029 MU, below the criterion of 0.0032 MU. The maximum error of the absolute dose was 0.4% and the maximum variation of the range was 0.1 mm. Conclusion: It was confirmed with measurements of the beam that the accuracy of the proton beam met the criteria with external gating signals. This research was supported by the Cabinet Office, Government of Japan and the Japan Society for the Promotion of Science (JSPS) through the Funding Program for World-Leading Innovative R and D on Science and Technology (FIRST Program

  15. Effects of training and simulated combat stress on leg tourniquet application accuracy, time, and effectiveness.

    PubMed

    Schreckengaust, Richard; Littlejohn, Lanny; Zarow, Gregory J

    2014-02-01

    The lower extremity tourniquet failure rate remains significantly higher in combat than in preclinical testing, so we hypothesized that tourniquet placement accuracy, speed, and effectiveness would improve during training and decline during simulated combat. Navy Hospital Corpsman (N = 89), enrolled in a Tactical Combat Casualty Care training course in preparation for deployment, applied Combat Application Tourniquet (CAT) and the Special Operations Forces Tactical Tourniquet (SOFT-T) on day 1 and day 4 of classroom training, then under simulated combat, wherein participants ran an obstacle course to apply a tourniquet while wearing full body armor and avoiding simulated small arms fire (paint balls). Application time and pulse elimination effectiveness improved day 1 to day 4 (p < 0.005). Under simulated combat, application time slowed significantly (p < 0.001), whereas accuracy and effectiveness declined slightly. Pulse elimination was poor for CAT (25% failure) and SOFT-T (60% failure) even in classroom conditions following training. CAT was more quickly applied (p < 0.005) and more effective (p < 0.002) than SOFT-T. Training fostered fast and effective application of leg tourniquets while performance declined under simulated combat. The inherent efficacy of tourniquet products contributes to high failure rates under combat conditions, pointing to the need for superior tourniquets and for rigorous deployment preparation training in simulated combat scenarios.

  16. The Study of the Tether Motion with Time-Varying Length Using the Absolute Nodal Coordinate Formulation with Multiple Nonlinear Time Scales

    NASA Astrophysics Data System (ADS)

    Kawaguti, Keisuke; Terumichi, Yoshiaki; Takehara, Shoichiro; Kaczmarczyk, Stefan; Sogabe, Kiyoshi

    In this study, the modeling and formulation for tether motion with time-varying length, large rotation, large displacement and large deformation are proposed. A tether or cable is an important element in lift systems, construction machines for transportation and often is used with a time-varying length. In some cases, these systems are large and the tether has a long length, large deformation and large displacement. The dynamic behavior of a tether in extension and retraction using the proposed method is discussed in this paper. In the passage through resonance, significant tether motions with large rotation and large deformation result. In the analysis of this phenomenon, the transient fluctuations of the motion amplitudes are examined and compared with the corresponding steady state motions. The accuracy and the cost of the calculations are also verified by comparison with the experimental results.

  17. A PC parallel port button box provides millisecond response time accuracy under Linux.

    PubMed

    Stewart, Neil

    2006-02-01

    For psychologists, it is sometimes necessary to measure people's reaction times to the nearest millisecond. This article describes how to use the PC parallel port to receive signals from a button box to achieve millisecond response time accuracy. The workings of the parallel port, the corresponding port addresses, and a simple Linux program for controlling the port are described. A test of the speed and reliability of button box signal detection is reported. If the reader is moderately familiar with Linux, this article should provide sufficient instruction for him or her to build and test his or her own parallel port button box. This article also describes how the parallel port could be used to control an external apparatus.

  18. Temporal Dynamics of Microbial Rhodopsin Fluorescence Reports Absolute Membrane Voltage

    PubMed Central

    Hou, Jennifer H.; Venkatachalam, Veena; Cohen, Adam E.

    2014-01-01

    Plasma membrane voltage is a fundamentally important property of a living cell; its value is tightly coupled to membrane transport, the dynamics of transmembrane proteins, and to intercellular communication. Accurate measurement of the membrane voltage could elucidate subtle changes in cellular physiology, but existing genetically encoded fluorescent voltage reporters are better at reporting relative changes than absolute numbers. We developed an Archaerhodopsin-based fluorescent voltage sensor whose time-domain response to a stepwise change in illumination encodes the absolute membrane voltage. We validated this sensor in human embryonic kidney cells. Measurements were robust to variation in imaging parameters and in gene expression levels, and reported voltage with an absolute accuracy of 10 mV. With further improvements in membrane trafficking and signal amplitude, time-domain encoding of absolute voltage could be applied to investigate many important and previously intractable bioelectric phenomena. PMID:24507604

  19. Precision goniometer equipped with a 22-bit absolute rotary encoder.

    PubMed

    Xiaowei, Z; Ando, M; Jidong, W

    1998-05-01

    The calibration of a compact precision goniometer equipped with a 22-bit absolute rotary encoder is presented. The goniometer is a modified Huber 410 goniometer: the diffraction angles can be coarsely generated by a stepping-motor-driven worm gear and precisely interpolated by a piezoactuator-driven tangent arm. The angular accuracy of the precision rotary stage was evaluated with an autocollimator. It was shown that the deviation from circularity of the rolling bearing utilized in the precision rotary stage restricts the angular positioning accuracy of the goniometer, and results in an angular accuracy ten times larger than the angular resolution of 0.01 arcsec. The 22-bit encoder was calibrated by an incremental rotary encoder. It became evident that the accuracy of the absolute encoder is approximately 18 bit due to systematic errors.

  20. Accuracy of prospective space-time surveillance in detecting tuberculosis transmission.

    PubMed

    Verma, Aman; Schwartzman, Kevin; Behr, Marcel A; Zwerling, Alice; Allard, Robert; Rochefort, Christian M; Buckeridge, David L

    2014-04-01

    To improve detection of tuberculosis transmission, public health can supplement contact tracing with space-time surveillance. However, investigation of space-time clusters not due to transmission (false alarms), may lead to costly, unnecessary interventions. We measured the accuracy of prospective space-time surveillance in detecting tuberculosis transmission, assessing the number of clusters containing transmission and the false alarm rate. We simulated monthly prospective applications of a scan statistic using the home addresses and diagnosis dates of all 1566 culture-positive TB cases reported in Montreal during 1996-2007. We verified transmission within the space-time clusters by analyzing the TB genotype. Over 11.5 years, at 1.3 false alarms per month, we detected 89 transmission chains; at 0.05 false alarms per month we detected 5 transmission chains. We found evidence that prospective space-time surveillance for TB leads to a high false alarm rate, limiting its practical utility in settings with TB epidemiology similar to Montreal.

  1. Accuracy validation of T2L2 time transfer in co-location.

    PubMed

    Laas-Bourez, Myrtille; Courde, Clément; Samain, Etienne; Exertier, Pierre; Guillemot, Philippe; Torre, Jean-Marie; Martin, Nicolas; Foussard, Claude

    2015-02-01

    The Time Transfer by Laser Link (T2L2) experiment has been developed in close collaboration between Centre National d'Etudes Spatiales and Observatoire de la Côte d'Azur. The aim is to synchronize remote ultra-stable clocks over large-scale distances using two laser ranging stations. This ground to space time transfer has been derived from laser telemetry technology with dedicated space equipment designed to record arrival time of laser pulses on board the satellite. For 3 years, specific campaigns have been organized to prove T2L2 performance. In April 2012, we performed a 2-week campaign with our two laser ranging stations, Métrologie Optique and French Transportable Laser Ranging Station, to demonstrate the T2L2 time transfer accuracy in co-location. We have compared three independent time transfer techniques: T2L2, GPS, and direct measurement, with both an event timer and an interval counter. The most important result obtained in this campaign was a mean agreement between T2L2 and a direct comparison better than 200 ps. This is the first major step to validate the uncertainty budget of the entire T2L2 experiment. This paper focuses on this campaign setup and the obtained results. PMID:25643076

  2. Accuracy validation of T2L2 time transfer in co-location.

    PubMed

    Laas-Bourez, Myrtille; Courde, Clément; Samain, Etienne; Exertier, Pierre; Guillemot, Philippe; Torre, Jean-Marie; Martin, Nicolas; Foussard, Claude

    2015-02-01

    The Time Transfer by Laser Link (T2L2) experiment has been developed in close collaboration between Centre National d'Etudes Spatiales and Observatoire de la Côte d'Azur. The aim is to synchronize remote ultra-stable clocks over large-scale distances using two laser ranging stations. This ground to space time transfer has been derived from laser telemetry technology with dedicated space equipment designed to record arrival time of laser pulses on board the satellite. For 3 years, specific campaigns have been organized to prove T2L2 performance. In April 2012, we performed a 2-week campaign with our two laser ranging stations, Métrologie Optique and French Transportable Laser Ranging Station, to demonstrate the T2L2 time transfer accuracy in co-location. We have compared three independent time transfer techniques: T2L2, GPS, and direct measurement, with both an event timer and an interval counter. The most important result obtained in this campaign was a mean agreement between T2L2 and a direct comparison better than 200 ps. This is the first major step to validate the uncertainty budget of the entire T2L2 experiment. This paper focuses on this campaign setup and the obtained results.

  3. More than accuracy: Nonverbal dialects modulate the time course of vocal emotion recognition across cultures.

    PubMed

    Jiang, Xiaoming; Paulmann, Silke; Robin, Jessica; Pell, Marc D

    2015-06-01

    Using a gating paradigm, this study investigated the nature of the in-group advantage in vocal emotion recognition by comparing 2 distinct cultures. Pseudoutterances conveying 4 basic emotions, expressed in English and Hindi, were presented to English and Hindi listeners. In addition to hearing full utterances, each stimulus was gated from its onset to construct 5 processing intervals to pinpoint when the in-group advantage emerges, and whether this differs when listening to a foreign language (English participants judging Hindi) or a second language (Hindi participants judging English). An index of the mean emotion identification point for each group and unbiased measures of accuracy at each time point was calculated. Results showed that in each language condition, native listeners were faster and more accurate than non-native listeners to recognize emotions. The in-group advantage emerged in both conditions after processing 400 ms to 500 ms of acoustic information. In the bilingual Hindi group, greater oral proficiency in English predicted faster and more accurate recognition of English emotional expressions. Consistent with dialect theory, our findings provide new evidence that nonverbal dialects impede both the accuracy and the efficiency of vocal emotion processing in cross-cultural settings, even when individuals are highly proficient in the out-group target language.

  4. Intracranial aneurysms: Diagnostics accuracy of three-dimensional, fourier transform, time-of-flight MR angiography

    SciTech Connect

    Korogi, Yukunori; Takahashi, Mutsumasa; Mabuchi, Nobuhisa; Miki, Hitoshi; Fujiwara, Satoru; Horikawa, Yoshiharu; Nakagawa, Toshio; O`Uchi, Toshihiro; Watabe, Tsuneya; Shiga, Hayao

    1994-10-01

    To assess the accuracy of three-dimensional, Fourier transform, time-of-flight magnetic resonance (MR) angiography in the identification of intracranial aneurysms. MR angiograms of 126 patients (59 male and 67 female patients, aged 12-77 years) with various intracranial vascular lesions were evaluated. Seventy-eight aneurysms, including 60 less than 5 mm in diameter, in 61 patients were depicted at conventional angiography. Eight projection images, as well as one axial collapsed MR angiogram obtained with a maximum-intensity projection algorithm, were used for evaluation. Sensitivity for the five observers ranged from 58% to 68% (mean, 63%). Higher sensitivity was achieved for anterior communicating and middle cerebral artery aneurysms, while that for internal carotid artery aneurysms was poor. Sensitivities for small and medium aneurysms ranged from 50% to 60% (mean, 56%) and from 77% to 94% (mean, 85%), respectively. MR angiography can depict intracranial aneurysms 5 mm or larger with good accuracy but is less useful for the identification of smaller aneurysms. 12 refs., 5 figs., 5 tabs.

  5. Sex differences in accuracy and precision when judging time to arrival: data from two Internet studies.

    PubMed

    Sanders, Geoff; Sinclair, Kamila

    2011-12-01

    We report two Internet studies that investigated sex differences in the accuracy and precision of judging time to arrival. We used accuracy to mean the ability to match the actual time to arrival and precision to mean the consistency with which each participant made their judgments. Our task was presented as a computer game in which a toy UFO moved obliquely towards the participant through a virtual three-dimensional space on route to a docking station. The UFO disappeared before docking and participants pressed their space bar at the precise moment they thought the UFO would have docked. Study 1 showed it was possible to conduct quantitative studies of spatiotemporal judgments in virtual reality via the Internet and confirmed reports that men are more accurate because women underestimate, but found no difference in precision measured as intra-participant variation. Study 2 repeated Study 1 with five additional presentations of one condition to provide a better measure of precision. Again, men were more accurate than women but there were no sex differences in precision. However, within the coincidence-anticipation timing (CAT) literature, of those studies that report sex differences, a majority found that males are both more accurate and more precise than females. Noting that many CAT studies report no sex differences, we discuss appropriate interpretations of such null findings. While acknowledging that CAT performance may be influenced by experience we suggest that the sex difference may have originated among our ancestors with the evolutionary selection of men for hunting and women for gathering. PMID:21125324

  6. Prismatic displacement effect of progressive multifocal glasses on reaction time and accuracy in elderly people

    PubMed Central

    Ellison, Ashton C; Campbell, A John; Robertson, M Clare; Sanderson, Gordon F

    2014-01-01

    Background Multifocal glasses (bifocals, trifocals, and progressives) increase the risk of falling in elderly people, but how they do so is unclear. To explain why glasses with progressive addition lenses increase the risk of falls and whether this can be attributed to false projection, this study aimed to 1) map the prismatic displacement of a progressive lens, and 2) test whether this displacement impaired reaction time and accuracy. Methods The reaction times of healthy ≥75-year-olds (31 participants) were measured when grasping for a bar and touching a black line. Participants performed each test twice, wearing their progressives and new, matched single vision (distance) glasses in random order. The line and bar targets were positioned according to the maximum and minimum prismatic displacement effect through the progressive lens, mapped using a focimeter. Results Progressive spectacle lenses have large areas of prismatic displacement in the central visual axis and edges. Reaction time was faster for progressives compared with single vision glasses with a centrally-placed horizontal grab bar (mean difference 101 ms, P=0.011 [repeated measures analysis]) and a horizontal black line placed 300 mm below center (mean difference 80 ms, P=0.007). There was no difference in accuracy between the two types of glasses. Conclusion Older people appear to adapt to the false projection of progressives in the central visual axis. This adaptation means that swapping to new glasses or a large change in prescription may lead to a fall. Frequently updating glasses may be more beneficial. PMID:24872674

  7. Effect of Variations in IRU Integration Time Interval On Accuracy of Aqua Attitude Estimation

    NASA Technical Reports Server (NTRS)

    Natanson, G. A.; Tracewell, Dave

    2003-01-01

    During Aqua launch support, attitude analysts noticed several anomalies in Onboard Computer (OBC) rates and in rates computed by the ground Attitude Determination System (ADS). These included: 1) periodic jumps in the OBC pitch rate every 2 minutes; 2) spikes in ADS pitch rate every 4 minutes; 3) close agreement between pitch rates computed by ADS and those derived from telemetered OBC quaternions (in contrast to the step-wise pattern observed for telemetered OBC rates); 4) spikes of +/- 10 milliseconds in telemetered IRU integration time every 4 minutes (despite the fact that telemetered time tags of any two sequential IRU measurements were always 1 second apart from each other). An analysis presented in the paper explains this anomalous behavior by a small average offset of about 0.5 +/- 0.05 microsec in the time interval between two sequential accumulated angle measurements. It is shown that errors in the estimated pitch angle due to neglecting the aforementioned variations in the integration time interval by the OBC is within +/- 2 arcseconds. Ground attitude solutions are found to be accurate enough to see the effect of the variations on the accuracy of the estimated pitch angle.

  8. Deconvolution improves the accuracy and depth sensitivity of time-resolved measurements

    NASA Astrophysics Data System (ADS)

    Diop, Mamadou; St. Lawrence, Keith

    2013-03-01

    Time-resolved (TR) techniques have the potential to distinguish early- from late-arriving photons. Since light travelling through superficial tissue is detected earlier than photons that penetrate the deeper layers, time-windowing can in principle be used to improve the depth sensitivity of TR measurements. However, TR measurements also contain instrument contributions - referred to as the instrument-response-function (IRF) - which cause temporal broadening of the measured temporal-point-spread-function (TPSF). In this report, we investigate the influence of the IRF on pathlength-resolved absorption changes (Δμa) retrieved from TR measurements using the microscopic Beer-Lambert law (MBLL). TPSFs were acquired on homogeneous and two-layer tissue-mimicking phantoms with varying optical properties. The measured IRF and TPSFs were deconvolved to recover the distribution of time-of-flights (DTOFs) of the detected photons. The microscopic Beer-Lambert law was applied to early and late time-windows of the TPSFs and DTOFs to access the effects of the IRF on pathlength-resolved Δμa. The analysis showed that the late part of the TPSFs contains substantial contributions from early-arriving photons, due to the smearing effects of the IRF, which reduced its sensitivity to absorption changes occurring in deep layers. We also demonstrated that the effects of the IRF can be efficiently eliminated by applying a robust deconvolution technique, thereby improving the accuracy and sensitivity of TR measurements to deep-tissue absorption changes.

  9. Improving Accuracy in Arrhenius Models of Cell Death: Adding a Temperature-Dependent Time Delay.

    PubMed

    Pearce, John A

    2015-12-01

    The Arrhenius formulation for single-step irreversible unimolecular reactions has been used for many decades to describe the thermal damage and cell death processes. Arrhenius predictions are acceptably accurate for structural proteins, for some cell death assays, and for cell death at higher temperatures in most cell lines, above about 55 °C. However, in many cases--and particularly at hyperthermic temperatures, between about 43 and 55 °C--the particular intrinsic cell death or damage process under study exhibits a significant "shoulder" region that constant-rate Arrhenius models are unable to represent with acceptable accuracy. The primary limitation is that Arrhenius calculations always overestimate the cell death fraction, which leads to severely overoptimistic predictions of heating effectiveness in tumor treatment. Several more sophisticated mathematical model approaches have been suggested and show much-improved performance. But simpler models that have adequate accuracy would provide useful and practical alternatives to intricate biochemical analyses. Typical transient intrinsic cell death processes at hyperthermic temperatures consist of a slowly developing shoulder region followed by an essentially constant-rate region. The shoulder regions have been demonstrated to arise chiefly from complex functional protein signaling cascades that generate delays in the onset of the constant-rate region, but may involve heat shock protein activity as well. This paper shows that acceptably accurate and much-improved predictions in the simpler Arrhenius models can be obtained by adding a temperature-dependent time delay. Kinetic coefficients and the appropriate time delay are obtained from the constant-rate regions of the measured survival curves. The resulting predictions are seen to provide acceptably accurate results while not overestimating cell death. The method can be relatively easily incorporated into numerical models. Additionally, evidence is presented

  10. Improving Accuracy in Arrhenius Models of Cell Death: Adding a Temperature-Dependent Time Delay.

    PubMed

    Pearce, John A

    2015-12-01

    The Arrhenius formulation for single-step irreversible unimolecular reactions has been used for many decades to describe the thermal damage and cell death processes. Arrhenius predictions are acceptably accurate for structural proteins, for some cell death assays, and for cell death at higher temperatures in most cell lines, above about 55 °C. However, in many cases--and particularly at hyperthermic temperatures, between about 43 and 55 °C--the particular intrinsic cell death or damage process under study exhibits a significant "shoulder" region that constant-rate Arrhenius models are unable to represent with acceptable accuracy. The primary limitation is that Arrhenius calculations always overestimate the cell death fraction, which leads to severely overoptimistic predictions of heating effectiveness in tumor treatment. Several more sophisticated mathematical model approaches have been suggested and show much-improved performance. But simpler models that have adequate accuracy would provide useful and practical alternatives to intricate biochemical analyses. Typical transient intrinsic cell death processes at hyperthermic temperatures consist of a slowly developing shoulder region followed by an essentially constant-rate region. The shoulder regions have been demonstrated to arise chiefly from complex functional protein signaling cascades that generate delays in the onset of the constant-rate region, but may involve heat shock protein activity as well. This paper shows that acceptably accurate and much-improved predictions in the simpler Arrhenius models can be obtained by adding a temperature-dependent time delay. Kinetic coefficients and the appropriate time delay are obtained from the constant-rate regions of the measured survival curves. The resulting predictions are seen to provide acceptably accurate results while not overestimating cell death. The method can be relatively easily incorporated into numerical models. Additionally, evidence is presented

  11. ABSOLUTE POLARIMETRY AT RHIC.

    SciTech Connect

    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.

  12. Accuracy of spirometric and flow-volume indices obtained by digitizing volume-time tracings.

    PubMed

    O'Donnell, C R; Sneddon, S L; Schenker, M; Garshick, E; Speizer, F E; Mead, J

    1987-07-01

    We tested the accuracy of a new system for deriving standard spirometric indices, maximal expiratory flow rates, and slope ratios from volume-time tracings. A computer-based technique employing a hand-operated cursor was used to put discrete values of volume and time into a memory array. Spirometric values obtained on 102 subjects using the computer system were compared with the corresponding "hand-read" values. The difference between the 2 measuring techniques were not significant for the FVC, the FEV75, and the FEF25-75; however, the average FEV1 differed by 6.7 ml (SD, 20.3 ml), which was significant. In addition, 10 subjects performed FVC maneuvers through a spirometer and flowmeter connected in series. Flows and slope ratios obtained from the volume-time tracings were compared with those obtained directly from the flowmeter. There was a high degree of correlation between the 2 types of flow measurements (r = 0.989), whereas slope ratios were less well correlated (r = 0.589). Configurational detail such as the presence of "bumps" on slope ratio versus volume plots were recovered with the computer technique. Using this new system, it is possible for 1 operator to process 10 to 12 sets of spirometry tracings per hour. PMID:3605826

  13. High-accuracy time- and space-resolved Stark shift measurements

    SciTech Connect

    Bailey, J.E.; Adams, R.; Carlson, A.L.; Ching, C.H.; Filuk, A.B.; Lake, P.

    1996-07-01

    Stark-shift measurements using emission spectroscopy are a powerful tool for advancing understanding in many plasma physics experiments. The authors use simultaneous 2-D-spatial and time-resolved spectra to study the electric field evolution in the 20 TW Particle Beam Fusion Accelerator II ion diode acceleration gap. Fiber optic arrays transport light from the gap to remote streaked spectrographs operated in a multiplexed mode that enables recording time-resolved spectra from eight spatial locations on a single instrument. Design optimization and characterization measurements of the multiplexed spectrograph properties include the astigmatism, resolution, dispersion variation, and sensitivity. A semi-automated line-fitting procedure determines the Stark shift and the related uncertainties. Fields up to 10 MV/cm are measured with an accuracy {+-}2--4%. Detailed tests of the fitting procedure confirm that the wavelength shift uncertainties are accurate to better than {+-}20%. Development of an active spectroscopy probe technique that uses laser-induced fluorescence from an injected atomic beam to obtain 3-D space- and time-resolved measurements of the electric and magnetic fields is in progress.

  14. Using precise word timing information improves decoding accuracy in a multiband-accelerated multimodal reading experiment.

    PubMed

    Vu, An T; Phillips, Jeffrey S; Kay, Kendrick; Phillips, Matthew E; Johnson, Matthew R; Shinkareva, Svetlana V; Tubridy, Shannon; Millin, Rachel; Grossman, Murray; Gureckis, Todd; Bhattacharyya, Rajan; Yacoub, Essa

    2016-01-01

    The blood-oxygen-level-dependent (BOLD) signal measured in functional magnetic resonance imaging (fMRI) experiments is generally regarded as sluggish and poorly suited for probing neural function at the rapid timescales involved in sentence comprehension. However, recent studies have shown the value of acquiring data with very short repetition times (TRs), not merely in terms of improvements in contrast to noise ratio (CNR) through averaging, but also in terms of additional fine-grained temporal information. Using multiband-accelerated fMRI, we achieved whole-brain scans at 3-mm resolution with a TR of just 500 ms at both 3T and 7T field strengths. By taking advantage of word timing information, we found that word decoding accuracy across two separate sets of scan sessions improved significantly, with better overall performance at 7T than at 3T. The effect of TR was also investigated; we found that substantial word timing information can be extracted using fast TRs, with diminishing benefits beyond TRs of 1000 ms. PMID:27686111

  15. Using precise word timing information improves decoding accuracy in a multiband-accelerated multimodal reading experiment.

    PubMed

    Vu, An T; Phillips, Jeffrey S; Kay, Kendrick; Phillips, Matthew E; Johnson, Matthew R; Shinkareva, Svetlana V; Tubridy, Shannon; Millin, Rachel; Grossman, Murray; Gureckis, Todd; Bhattacharyya, Rajan; Yacoub, Essa

    2016-01-01

    The blood-oxygen-level-dependent (BOLD) signal measured in functional magnetic resonance imaging (fMRI) experiments is generally regarded as sluggish and poorly suited for probing neural function at the rapid timescales involved in sentence comprehension. However, recent studies have shown the value of acquiring data with very short repetition times (TRs), not merely in terms of improvements in contrast to noise ratio (CNR) through averaging, but also in terms of additional fine-grained temporal information. Using multiband-accelerated fMRI, we achieved whole-brain scans at 3-mm resolution with a TR of just 500 ms at both 3T and 7T field strengths. By taking advantage of word timing information, we found that word decoding accuracy across two separate sets of scan sessions improved significantly, with better overall performance at 7T than at 3T. The effect of TR was also investigated; we found that substantial word timing information can be extracted using fast TRs, with diminishing benefits beyond TRs of 1000 ms.

  16. Time-dependent classification accuracy curve under marker-dependent sampling.

    PubMed

    Zhu, Zhaoyin; Wang, Xiaofei; Saha-Chaudhuri, Paramita; Kosinski, Andrzej S; George, Stephen L

    2016-07-01

    Evaluating the classification accuracy of a candidate biomarker signaling the onset of disease or disease status is essential for medical decision making. A good biomarker would accurately identify the patients who are likely to progress or die at a particular time in the future or who are in urgent need for active treatments. To assess the performance of a candidate biomarker, the receiver operating characteristic (ROC) curve and the area under the ROC curve (AUC) are commonly used. In many cases, the standard simple random sampling (SRS) design used for biomarker validation studies is costly and inefficient. In order to improve the efficiency and reduce the cost of biomarker validation, marker-dependent sampling (MDS) may be used. In a MDS design, the selection of patients to assess true survival time is dependent on the result of a biomarker assay. In this article, we introduce a nonparametric estimator for time-dependent AUC under a MDS design. The consistency and the asymptotic normality of the proposed estimator is established. Simulation shows the unbiasedness of the proposed estimator and a significant efficiency gain of the MDS design over the SRS design. PMID:27119599

  17. Absolute transition probabilities of phosphorus.

    NASA Technical Reports Server (NTRS)

    Miller, M. H.; Roig, R. A.; Bengtson, R. D.

    1971-01-01

    Use of a gas-driven shock tube to measure the absolute strengths of 21 P I lines and 126 P II lines (from 3300 to 6900 A). Accuracy for prominent, isolated neutral and ionic lines is estimated to be 28 to 40% and 18 to 30%, respectively. The data and the corresponding theoretical predictions are examined for conformity with the sum rules.-

  18. The accuracy of current methods in determining the timing of epiphysiodesis.

    PubMed

    Lee, S C; Shim, J S; Seo, S W; Lim, K S; Ko, K R

    2013-07-01

    We compared the accuracy of the growth remaining method of assessing leg-length discrepancy (LLD) with the straight-line graph method, the multiplier method and their variants. We retrospectively reviewed the records of 44 patients treated by percutaneous epiphysiodesis for LLD. All were followed up until maturity. We used the modified Green-Anderson growth-remaining method (Method 1) to plan the timing of epiphysiodesis. Then we presumed that the other four methods described below were used pre-operatively for calculating the timing of epiphysiodesis. We then assumed that these four methods were used pre-operatively. Method 2 was the original Green-Anderson growth-remaining method; Method 3, Paley's multiplier method using bone age; Method 4, Paley's multiplier method using chronological age; and Method 5, Moseley's straight-line graph method. We compared 'Expected LLD at maturity with surgery' with 'Final LLD at maturity with surgery' for each method. Statistical analysis revealed that 'Expected LLD at maturity with surgery' was significantly different from 'Final LLD at maturity with surgery'. Method 2 was the most accurate. There was a significant correlation between 'Expected LLD at maturity with surgery' and 'Final LLD at maturity with surgery', the greatest correlation being with Method 2. Generally all the methods generated an overcorrected value. No method generates the precise 'Expected LLD at maturity with surgery'. It is essential that an analysis of the pattern of growth is taken into account when predicting final LLD. As many additional data as possible are required.

  19. Standardization of Gene Expression Quantification by Absolute Real-Time qRT-PCR System Using a Single Standard for Marker and Reference Genes.

    PubMed

    Zhou, Yi-Hong; Raj, Vinay R; Siegel, Eric; Yu, Liping

    2010-08-16

    In the last decade, genome-wide gene expression data has been collected from a large number of cancer specimens. In many studies utilizing either microarray-based or knowledge-based gene expression profiling, both the validation of candidate genes and the identification and inclusion of biomarkers in prognosis-modeling has employed real-time quantitative PCR on reverse transcribed mRNA (qRT-PCR) because of its inherent sensitivity and quantitative nature. In qRT-PCR data analysis, an internal reference gene is used to normalize the variation in input sample quantity. The relative quantification method used in current real-time qRT-PCR analysis fails to ensure data comparability pivotal in identification of prognostic biomarkers. By employing an absolute qRT-PCR system that uses a single standard for marker and reference genes (SSMR) to achieve absolute quantification, we showed that the normalized gene expression data is comparable and independent of variations in the quantities of sample as well as the standard used for generating standard curves. We compared two sets of normalized gene expression data with same histological diagnosis of brain tumor from two labs using relative and absolute real-time qRT-PCR. Base-10 logarithms of the gene expression ratio relative to ACTB were evaluated for statistical equivalence between tumors processed by two different labs. The results showed an approximate comparability for normalized gene expression quantified using a SSMR-based qRT-PCR. Incomparable results were seen for the gene expression data using relative real-time qRT-PCR, due to inequality in molar concentration of two standards for marker and reference genes. Overall results show that SSMR-based real-time qRT-PCR ensures comparability of gene expression data much needed in establishment of prognostic/predictive models for cancer patients-a process that requires large sample sizes by combining independent sets of data.

  20. Impact of time-variable vegetation on accuracy of rapid hydrologic predictions

    NASA Astrophysics Data System (ADS)

    Stec, Magdalena; Niedzielski, Tomasz

    2016-04-01

    It is crucial to identify the processes that impact errors of hydrologic forecasts. Since existence of vegetation and its ability to store precipitation is an important element of water distribution in the catchment, especially at the beginning of a rainfall event, it may be considered as one of the processes influencing skills of hydrological forecasts. The main objective of the study is to verify the hypothesis that water level predictions are controlled by vegetation dynamics in the contributing mountainous basins. The analysis is conducted for the upper Nysa Klodzka catchment with the outlet in Bardo (SW Poland). The basin includes a mid-mountain abasement covered with crops, while surrounding medium-altitude mountain ranges are mainly covered with forests. We focus on the entire year, from autumn 2013 to summer 2014. Herein, we analyze prediction errors and efficiency measures of hydrologic forecasts provided by two stochastic models - uni- and multivariate autoregressive models as well as their two-model ensemble prediction. In addition, we use the satellite-derived Leaf Area Index (LAI) images from the Moderate Resolution Imaging Spectroradiometer (MODIS). Hydrological prognoses are derived by the HydroProg real-time rapid forecasting system, built at the University of Wroclaw (Poland) in frame of the research project 2011/01/D/ST10/04171 of the National Science Centre of Poland. Correlation analysis between the plant maximum water storage capacity and prediction error/skill statistics (mean absolute error, root mean square error, Nash-Sutcliffe efficiency , index of agreement) is conducted. To cope with small sample size, the bootstrap simulation is performed. We conclude that there is a strong negative association between mean or median prediction errors and vegetation state for all meteorological seasons of a year. This result implies that basins with higher interception potential are more vulnerable to forecast inaccuracy than those with sparse natural

  1. A high accuracy broadband measurement system for time resolved complex bioimpedance measurements.

    PubMed

    Kaufmann, S; Malhotra, A; Ardelt, G; Ryschka, M

    2014-06-01

    Bioimpedance measurements are useful tools in biomedical engineering and life science. Bioimpedance is the electrical impedance of living tissue and can be used in the analysis of various physiological parameters. Bioimpedance is commonly measured by injecting a small well known alternating current via surface electrodes into an object under test and measuring the resultant surface voltages. It is non-invasive, painless and has no known hazards. This work presents a field programmable gate array based high accuracy broadband bioimpedance measurement system for time resolved bioimpedance measurements. The system is able to measure magnitude and phase of complex impedances under test in a frequency range of about 10-500 kHz with excitation currents from 10 µA to 5 mA. The overall measurement uncertainties stay below 1% for the impedance magnitude and below 0.5° for the phase in most measurement ranges. Furthermore, the described system has a sample rate of up to 3840 impedance spectra per second. The performance of the bioimpedance measurement system is demonstrated with a resistor based system calibration and with measurements on biological samples.

  2. Curbside radiology consults: how does the time allotted for review, level of training, and subspecialization affect interpretation accuracy?

    PubMed

    Jordanov, Martin; Bregman, Jana; Montgomery, Kathleen; Heidel, Mark

    2015-01-01

    The interpretation accuracy of resident and attending radiologists was assessed based on time allotted for study review, level of training, and subspecialization. Twelve cases were presented in a time-constrained and a time-unconstrained fashion to eight residents and six attendings. Overall, timed and untimed diagnostic accuracy was similar for all groups tested. Attendings sometimes performed worse than residents and in-field attendings when reviewing out-of-field studies. Residents often had greater specialty-specific accuracy than out-of-field attendings. Residents are capable of providing accurate "curbside" consultations to referring clinicians even under time-constrained conditions. Highly subspecialized attending radiologists should be cognizant of their out-of-field limitations. PMID:25725945

  3. Absolute optical metrology : nanometers to kilometers

    NASA Technical Reports Server (NTRS)

    Dubovitsky, Serge; Lay, O. P.; Peters, R. D.; Liebe, C. C.

    2005-01-01

    We provide and overview of the developments in the field of high-accuracy absolute optical metrology with emphasis on space-based applications. Specific work on the Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor is described along with novel applications of the sensor.

  4. Factors Affecting Accuracy and Time Requirements of a Glucose Oxidase-Peroxidase Assay for Determination of Glucose

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate and rapid assays for glucose are desirable for analysis of glucose and starch in food and feedstuffs. An established colorimetric glucose oxidase-peroxidase method for glucose was modified to reduce analysis time, and evaluated for factors that affected accuracy. Time required to perform t...

  5. A method for in situ absolute DD yield calibration of neutron time-of-flight detectors on OMEGA using CR-39-based proton detectors.

    PubMed

    Waugh, C J; Rosenberg, M J; Zylstra, A B; Frenje, J A; Séguin, F H; Petrasso, R D; Glebov, V Yu; Sangster, T C; Stoeckl, C

    2015-05-01

    Neutron time of flight (nTOF) detectors are used routinely to measure the absolute DD neutron yield at OMEGA. To check the DD yield calibration of these detectors, originally calibrated using indium activation systems, which in turn were cross-calibrated to NOVA nTOF detectors in the early 1990s, a direct in situ calibration method using CR-39 range filter proton detectors has been successfully developed. By measuring DD neutron and proton yields from a series of exploding pusher implosions at OMEGA, a yield calibration coefficient of 1.09 ± 0.02 (relative to the previous coefficient) was determined for the 3m nTOF detector. In addition, comparison of these and other shots indicates that significant reduction in charged particle flux anisotropies is achieved when bang time occurs significantly (on the order of 500 ps) after the trailing edge of the laser pulse. This is an important observation as the main source of the yield calibration error is due to particle anisotropies caused by field effects. The results indicate that the CR-39-nTOF in situ calibration method can serve as a valuable technique for calibrating and reducing the uncertainty in the DD absolute yield calibration of nTOF detector systems on OMEGA, the National Ignition Facility, and laser megajoule. PMID:26026524

  6. A method for in situ absolute DD yield calibration of neutron time-of-flight detectors on OMEGA using CR-39-based proton detectors

    SciTech Connect

    Waugh, C. J. Zylstra, A. B.; Frenje, J. A.; Séguin, F. H.; Petrasso, R. D.; Rosenberg, M. J.; Glebov, V. Yu.; Sangster, T. C.; Stoeckl, C.

    2015-05-15

    Neutron time of flight (nTOF) detectors are used routinely to measure the absolute DD neutron yield at OMEGA. To check the DD yield calibration of these detectors, originally calibrated using indium activation systems, which in turn were cross-calibrated to NOVA nTOF detectors in the early 1990s, a direct in situ calibration method using CR-39 range filter proton detectors has been successfully developed. By measuring DD neutron and proton yields from a series of exploding pusher implosions at OMEGA, a yield calibration coefficient of 1.09 ± 0.02 (relative to the previous coefficient) was determined for the 3m nTOF detector. In addition, comparison of these and other shots indicates that significant reduction in charged particle flux anisotropies is achieved when bang time occurs significantly (on the order of 500 ps) after the trailing edge of the laser pulse. This is an important observation as the main source of the yield calibration error is due to particle anisotropies caused by field effects. The results indicate that the CR-39-nTOF in situ calibration method can serve as a valuable technique for calibrating and reducing the uncertainty in the DD absolute yield calibration of nTOF detector systems on OMEGA, the National Ignition Facility, and laser megajoule.

  7. A method for in situ absolute DD yield calibration of neutron time-of-flight detectors on OMEGA using CR-39-based proton detectors

    DOE PAGES

    Waugh, C. J.; Rosenberg, M. J.; Zylstra, A. B.; Frenje, J. A.; Seguin, F. H.; Petrasso, R. D.; Glebov, V. Yu.; Sangster, T. C.; Stoeckl, C.

    2015-05-27

    Neutron time of flight (nTOF) detectors are used routinely to measure the absolute DD neutron yield at OMEGA. To check the DD yield calibration of these detectors, originally calibrated using indium activation systems, which in turn were cross-calibrated to NOVA nTOF detectors in the early 1990s, a direct in situ calibration method using CR-39 range filter proton detectors has been successfully developed. By measuring DD neutron and proton yields from a series of exploding pusher implosions at OMEGA, a yield calibration coefficient of 1.09 ± 0.02 (relative to the previous coefficient) was determined for the 3m nTOF detector. In addition,more » comparison of these and other shots indicates that significant reduction in charged particle flux anisotropies is achieved when bang time occurs significantly (on the order of 500 ps) after the trailing edge of the laser pulse. This is an important observation as the main source of the yield calibration error is due to particle anisotropies caused by field effects. The results indicate that the CR-39-nTOF in situ calibration method can serve as a valuable technique for calibrating and reducing the uncertainty in the DD absolute yield calibration of nTOF detector systems on OMEGA, the National Ignition Facility, and laser megajoule.« less

  8. A method for in situ absolute DD yield calibration of neutron time-of-flight detectors on OMEGA using CR-39-based proton detectors

    SciTech Connect

    Waugh, C. J.; Rosenberg, M. J.; Zylstra, A. B.; Frenje, J. A.; Seguin, F. H.; Petrasso, R. D.; Glebov, V. Yu.; Sangster, T. C.; Stoeckl, C.

    2015-05-27

    Neutron time of flight (nTOF) detectors are used routinely to measure the absolute DD neutron yield at OMEGA. To check the DD yield calibration of these detectors, originally calibrated using indium activation systems, which in turn were cross-calibrated to NOVA nTOF detectors in the early 1990s, a direct in situ calibration method using CR-39 range filter proton detectors has been successfully developed. By measuring DD neutron and proton yields from a series of exploding pusher implosions at OMEGA, a yield calibration coefficient of 1.09 ± 0.02 (relative to the previous coefficient) was determined for the 3m nTOF detector. In addition, comparison of these and other shots indicates that significant reduction in charged particle flux anisotropies is achieved when bang time occurs significantly (on the order of 500 ps) after the trailing edge of the laser pulse. This is an important observation as the main source of the yield calibration error is due to particle anisotropies caused by field effects. The results indicate that the CR-39-nTOF in situ calibration method can serve as a valuable technique for calibrating and reducing the uncertainty in the DD absolute yield calibration of nTOF detector systems on OMEGA, the National Ignition Facility, and laser megajoule.

  9. Influence of alginate impression materials and storage time on surface detail reproduction and dimensional accuracy of stone models.

    PubMed

    Guiraldo, Ricardo D; Moreti, Ana F F; Martinelli, Julia; Berger, Sandrine B; Meneghel, Luciana L; Caixeta, Rodrigo V; Sinhoreti, Mário A C

    2015-01-01

    This study compared the surface detail reproduction and dimensional accuracy of stone models obtained from molds prepared using different alginate impression materials (Cavex ColorChange, Hydrogum 5, or Jeltrate Plus) and with different storage times (1, 3, and 5 days) to models from molds that were filled immediately with no storage time. The molds were prepared over a matrix containing 50-μm line, (ISO 1563 standard) under pressure with a perforated metal tray. The molds were removed 2 minutes after loss of sticky consistency and either filled immediately or stored in closed jars at 100% relative humidity and 37°C for 1, 3, or 5 days. The molds were filled with dental plaster (Durone IV). Surface detail reproduction and dimensional accuracy were evaluated using optical microscopy on the 50-μm wide line, which was 25 mm in length, according to ISO 1563 standard. The dimensional accuracy results (%) were subjected to analysis of variance. The 50-μm wide line (ISO 1563 standard) was completely reproduced by all alginate impression materials regardless of the storage time. There was no statistically significant difference in the mean dimensional accuracy values of stone models made from molds composed of different alginate impression materials and with different storage times (p = 0.989). In conclusion, storing the mold for five days prior to filling did not change the surface detail reproduction or dimensional accuracy of the alginates examined in this study.

  10. High-accuracy real-time automatic thresholding for centroid tracker

    NASA Astrophysics Data System (ADS)

    Zhang, Ye; Wang, Yanjie

    2006-01-01

    Many of the video image trackers today use the centroid as the tracking point. In engineering, a target's centroid is computed from a binary image to reduce the processing time. Hence thresholding of gray level image to binary image is a decisive step in centroid tracking. How to choose the feat thresholds in clutter is still an intractability problem unsolved today. This paper introduces a high-accuracy real-time automatic thresholding method for centroid tracker. It works well for variety types of target tracking in clutter. The core of this method is to get the entire information contained in the histogram, such as the number of the peaks, their height, position and other properties in the histogram. Combine with this histogram analysis; we can get several key pairs of peaks which can include the target and the background around it and use the method of Otsu to get intensity thresholds from them. According to the thresholds, we can gain the binary image and get the centroid from it. To track the target, the paper also suggests subjoining an eyeshot-window, just like our eyes focus on a target, we will not miss it unless it is out of our eyeshot, the impression will help us to extract the target in clutter and track it and we will wait its emergence since it has been covered. To obtain the impression, the paper offers a idea comes from the method of Snakes; it give a great help for us to get a glancing size, so that we can compare the size of the object in the current frame with the former. If the change is little, we consider the object has been tracked well. Otherwise, if the change is bigger than usual, we should analyze the inflection in the histogram to find out what happened to the object. In general, what we have to do is turning the analysis into codes for the tracker to determine a feat threshold. The paper will show the steps in detail. The paper also discusses the hardware architecture which can meet the speed requirement.

  11. Teaching Absolute Value Meaningfully

    ERIC Educational Resources Information Center

    Wade, Angela

    2012-01-01

    What is the meaning of absolute value? And why do teachers teach students how to solve absolute value equations? Absolute value is a concept introduced in first-year algebra and then reinforced in later courses. Various authors have suggested instructional methods for teaching absolute value to high school students (Wei 2005; Stallings-Roberts…

  12. Assessment of fine motor skill in musicians and nonmusicians: differences in timing versus sequence accuracy in a bimanual fingering task.

    PubMed

    Kincaid, Anthony E; Duncan, Scott; Scott, Samuel A

    2002-08-01

    While professional musicians are generally considered to possess better control of finger movements than nonmusicians, relatively few reports have experimentally addressed the nature of this discrepancy in fine motor skills. For example, it is unknown whether musicians perform with greater skill than control subjects in all aspects of different types of fine motor activities. More specifically, it is not known whether musicians perform better than control subjects on a fine motor task that is similar, but not identical, to the playing of their primary instrument. The purpose of this study was to examine the accuracy of finger placement and accuracy of timing in professional musicians and nonmusicians using a simple, rhythmical, bilateral fingering pattern and the technology that allowed separate assessment of these two parameters. Professional musicians (other than pianists) and nonmusicians were given identical, detailed and explicit instructions but not allowed physically to practice the finger pattern. After verbally repeating the correct pattern for the investigator, subjects performed the task on an electric keyboard with both hands simultaneously. Each subject's performance was then converted to a numerical score. While musicians clearly demonstrated better accuracy in timing, no significant difference was found between the groups in their finger placement scores. These findings were not correlated with subjects' age, sex, limb dominance, or primary instrument (for the professional musicians). This study indicates that professional musicians perform better in timing accuracy but not spatial accuracy while executing a simple, novel, bimanual motor sequence. PMID:12365261

  13. Real-time diagnosis of H. pylori infection during endoscopy: Accuracy of an innovative tool (EndoFaster)

    PubMed Central

    Costamagna, Guido; Zullo, Angelo; Bizzotto, Alessandra; Hassan, Cesare; Riccioni, Maria Elena; Marmo, Clelia; Strangio, Giuseppe; Di Rienzo, Teresa Antonella; Cammarota, Giovanni; Gasbarrini, Antonio; Repici, Alessandro

    2015-01-01

    Background EndoFaster is novel device able to perform real-time ammonium measurement in gastric juice allowing H. pylori diagnosis during endoscopy. This large study aimed to validate the accuracy of EndoFaster for real-time H. pylori detection. Methods Consecutive patients who underwent upper endoscopy in two centres were prospectively enrolled. During endoscopy, 4 ml of gastric juice were aspirated to perform automatic analysis by EndoFaster within 90 seconds, and H. pylori was considered present (>62 ppm/ml) or absent (≤62 ppm/ml). Accuracy was measured by using histology as gold standard, and 13C-urea breath test (UBT) in discordant cases. Accuracy, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) were calculated. Results Overall, 189 patients were enrolled, but in seven (3.4%) the aspirated gastric juice amount was insufficient to perform the test. The accuracy, sensitivity, specificity, PPV, and NPV were 87.4%, 90.3%, 85.5%, 80.2%, 93.1%, respectively, and 92.6%, 97.1%, 89.7%, 85.9%, 98.0%, respectively, when H. pylori status was reclassified according to the UBT result in discordant cases. Conclusions This study found a high accuracy/feasibility of EndoFaster for real-time H. pylori diagnosis. Use of EndoFaster may allow selecting those patients in whom routine gastric biopsies could be avoided. PMID:27403299

  14. Sub-micron absolute distance measurements in sub-millisecond times with dual free-running femtosecond Er fiber-lasers.

    PubMed

    Liu, Tze-An; Newbury, Nathan R; Coddington, Ian

    2011-09-12

    We demonstrate a simplified dual-comb LIDAR setup for precision absolute ranging that can achieve a ranging precision of 2 μm in 140 μs acquisition time. With averaging, the precision drops below 1 μm at 0.8 ms and below 200 nm at 20 ms. The system can measure the distance to multiple targets with negligible dead zones and a ranging ambiguity of 1 meter. The system is much simpler than a previous coherent dual-comb LIDAR because the two combs are replaced by free-running, saturable-absorber-based femtosecond Er fiber lasers, rather than tightly phase-locked combs, with the entire time base provided by a single 10-digit frequency counter. Despite the simpler design, the system provides a factor of three improved performance over the previous coherent dual comb LIDAR system.

  15. Sub-micron absolute distance measurements in sub-millisecond times with dual free-running femtosecond Er fiber-lasers.

    PubMed

    Liu, Tze-An; Newbury, Nathan R; Coddington, Ian

    2011-09-12

    We demonstrate a simplified dual-comb LIDAR setup for precision absolute ranging that can achieve a ranging precision of 2 μm in 140 μs acquisition time. With averaging, the precision drops below 1 μm at 0.8 ms and below 200 nm at 20 ms. The system can measure the distance to multiple targets with negligible dead zones and a ranging ambiguity of 1 meter. The system is much simpler than a previous coherent dual-comb LIDAR because the two combs are replaced by free-running, saturable-absorber-based femtosecond Er fiber lasers, rather than tightly phase-locked combs, with the entire time base provided by a single 10-digit frequency counter. Despite the simpler design, the system provides a factor of three improved performance over the previous coherent dual comb LIDAR system. PMID:21935219

  16. Comprehensive panel of real-time TaqMan polymerase chain reaction assays for detection and absolute quantification of filoviruses, arenaviruses, and New World hantaviruses.

    PubMed

    Trombley, Adrienne R; Wachter, Leslie; Garrison, Jeffrey; Buckley-Beason, Valerie A; Jahrling, Jordan; Hensley, Lisa E; Schoepp, Randal J; Norwood, David A; Goba, Augustine; Fair, Joseph N; Kulesh, David A

    2010-05-01

    Viral hemorrhagic fever is caused by a diverse group of single-stranded, negative-sense or positive-sense RNA viruses belonging to the families Filoviridae (Ebola and Marburg), Arenaviridae (Lassa, Junin, Machupo, Sabia, and Guanarito), and Bunyaviridae (hantavirus). Disease characteristics in these families mark each with the potential to be used as a biological threat agent. Because other diseases have similar clinical symptoms, specific laboratory diagnostic tests are necessary to provide the differential diagnosis during outbreaks and for instituting acceptable quarantine procedures. We designed 48 TaqMan-based polymerase chain reaction (PCR) assays for specific and absolute quantitative detection of multiple hemorrhagic fever viruses. Forty-six assays were determined to be virus-specific, and two were designated as pan assays for Marburg virus. The limit of detection for the assays ranged from 10 to 0.001 plaque-forming units (PFU)/PCR. Although these real-time hemorrhagic fever virus assays are qualitative (presence of target), they are also quantitative (measure a single DNA/RNA target sequence in an unknown sample and express the final results as an absolute value (e.g., viral load, PFUs, or copies/mL) on the basis of concentration of standard samples and can be used in viral load, vaccine, and antiviral drug studies.

  17. Recognition accuracy and reaction time of vocal expressions of emotion by African-American and Euro-American college women.

    PubMed

    Weathers, Monica D; Kitsantas, Panagiota; Lever, Teresa; O'Brien, Patrick; Campbell, Stacy; Rastatter, Michael

    2004-10-01

    This study examined the relationship of racial group membership and vocal expressions of emotion. Recognition accuracy and reaction time were examined using the Diagnostic Assessment of Nonverbal Accuracy 2 Receptive Paralanguage subtests with 18 young Euro-American and African-American women. Participants listened to Euro-American children and adults speaking a neutral sentence, and identified the emotion as happy, sad, angry, or fearful. Analysis identified a significant effect for race on reaction time. Euro-American participants had faster mean RT than the African-American women for the recognition of vocal expression of emotion portrayed by Euro-Americans. However, no significant differences were found in mean accurate identification between the two groups. The finding of a significant difference in recognition RT but not in accuracy between the stimuli spoken by an adult and a child was unexpected. Both racial groups had faster mean RT in response to vocal expression of emotion by children. PMID:15560358

  18. Global absolut gravity reference system as replacement of IGSN 71

    NASA Astrophysics Data System (ADS)

    Wilmes, Herbert; Wziontek, Hartmut; Falk, Reinhard

    2015-04-01

    The determination of precise gravity field parameters is of great importance in a period in which earth sciences are achieving the necessary accuracy to monitor and document global change processes. This is the reason why experts from geodesy and metrology joined in a successful cooperation to make absolute gravity observations traceable to SI quantities, to improve the metrological kilogram definition and to monitor mass movements and smallest height changes for geodetic and geophysical applications. The international gravity datum is still defined by the International Gravity Standardization Net adopted in 1971 (IGSN 71). The network is based upon pendulum and spring gravimeter observations taken in the 1950s and 60s supported by the early free fall absolute gravimeters. Its gravity values agreed in every case to better than 0.1 mGal. Today, more than 100 absolute gravimeters are in use worldwide. The series of repeated international comparisons confirms the traceability of absolute gravity measurements to SI quantities and confirm the degree of equivalence of the gravimeters in the order of a few µGal. For applications in geosciences where e.g. gravity changes over time need to be analyzed, the temporal stability of an absolute gravimeter is most important. Therefore, the proposition is made to replace the IGSN 71 by an up-to-date gravity reference system which is based upon repeated absolute gravimeter comparisons and a global network of well controlled gravity reference stations.

  19. Note: electronic circuit for two-way time transfer via a single coaxial cable with picosecond accuracy and precision.

    PubMed

    Prochazka, Ivan; Kodet, Jan; Panek, Petr

    2012-11-01

    We have designed, constructed, and tested the overall performance of the electronic circuit for the two-way time transfer between two timing devices over modest distances with sub-picosecond precision and a systematic error of a few picoseconds. The concept of the electronic circuit enables to carry out time tagging of pulses of interest in parallel to the comparison of the time scales of these timing devices. The key timing parameters of the circuit are: temperature change of the delay is below 100 fs/K, timing stability time deviation better than 8 fs for averaging time from minutes to hours, sub-picosecond time transfer precision, and a few picoseconds time transfer accuracy.

  20. Absolute concentrations of highly vibrationally excited OH(υ = 9 + 8) in the mesopause region derived from the TIMED/SABER instrument

    NASA Astrophysics Data System (ADS)

    Mast, Jeffrey; Mlynczak, Martin G.; Hunt, Linda A.; Marshall, B. Thomas; Mertens, Christoper J.; Russell, James M.; Thompson, R. Earl; Gordley, Larry L.

    2013-02-01

    Abstract <span class="hlt">Absolute</span> concentrations (cm-3) of highly vibrationally excited hydroxyl (OH) are derived from measurements of the volume emission rate of the υ = 9 + 8 states of the OH radical made by the SABER instrument on the <span class="hlt">TIMED</span> satellite. SABER has exceptionally sensitive measurement precision that corresponds to an ability to detect changes in volume emission rate on the order of ~5 excited OH molecules per cm3. Peak zonal annual mean concentrations observed by SABER exceed 1000 cm-3 at night and 225 cm-3 during the day. Measurements since 2002 show an apparent altitude-dependent variation of the night OH(υ = 9 + 8) concentrations with the 11 year solar cycle, with concentrations decreasing below ~ 95 km from 2002 to 2008. These observations provide a global database for evaluating photochemical model computations of OH abundance, reaction kinetics, and rates and mechanisms responsible for maintaining vibrationally excited OH in the mesopause region.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_8");'>8</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li class="active"><span>10</span></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_10 --> <div id="page_11" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="201"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016EGUGA..1812195W','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016EGUGA..1812195W"><span id="translatedtitle">Continuous Gravity Monitoring in South America with Superconducting and <span class="hlt">Absolute</span> Gravimeters: More than 12 years <span class="hlt">time</span> series at station TIGO/Concepcion (Chile)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Wziontek, Hartmut; Falk, Reinhard; Hase, Hayo; Armin, Böer; Andreas, Güntner; Rongjiang, Wang</p> <p>2016-04-01</p> <p>As part of the Transportable Integrated Geodetic Observatory (TIGO) of BKG, the superconducting gravimeter SG 038 was set up in December 2002 at station Concepcion / Chile to record temporal gravity variations with highest precision. Since May 2006 the <span class="hlt">time</span> series was supported by weekly observations with the <span class="hlt">absolute</span> gravimeter FG5-227, proving the large seasonal variations of up to 30 μGal and establishing a gravity reference station in South America. With the move of the whole observatory to the new location near to La Plata / Argentina the series was terminated. Results of almost continuously monitoring gravity variations for more than 12 years are presented. Seasonal variations are interpreted with respect of global and local water storage changes and the impact of the 8.8 Maule Earthquake in February 2010 is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ASPC..503..233C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ASPC..503..233C"><span id="translatedtitle">SkyProbe: Real-<span class="hlt">Time</span> Precision Monitoring in the Optical of the <span class="hlt">Absolute</span> Atmospheric Absorption on the Telescope Science and Calibration Fields</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cuillandre, J.-C.; Magnier, E.; Sabin, D.; Mahoney, B.</p> <p>2016-05-01</p> <p>Mauna Kea is known for its pristine seeing conditions but sky transparency can be an issue for science operations since at least 25% of the observable (i.e. open dome) nights are not photometric, an effect mostly due to high-altitude cirrus. Since 2001, the original single channel SkyProbe mounted in parallel on the Canada-France-Hawaii Telescope (CFHT) has gathered one V-band exposure every minute during each observing night using a small CCD camera offering a very wide field of view (35 sq. deg.) encompassing the region pointed by the telescope for science operations, and exposures long enough (40 seconds) to capture at least 100 stars of Hipparcos' Tycho catalog at high galactic latitudes (and up to 600 stars at low galactic latitudes). The measurement of the true atmospheric absorption is achieved within 2%, a key advantage over all-sky direct thermal infrared imaging detection of clouds. The <span class="hlt">absolute</span> measurement of the true atmospheric absorption by clouds and particulates affecting the data being gathered by the telescope's main science instrument has proven crucial for decision making in the CFHT queued service observing (QSO) representing today all of the telescope <span class="hlt">time</span>. Also, science exposures taken in non-photometric conditions are automatically registered for a new observation at a later date at 1/10th of the original exposure <span class="hlt">time</span> in photometric conditions to ensure a proper final <span class="hlt">absolute</span> photometric calibration. Photometric standards are observed only when conditions are reported as being perfectly stable by SkyProbe. The more recent dual color system (simultaneous B & V bands) will offer a better characterization of the sky properties above Mauna Kea and should enable a better detection of the thinnest cirrus (absorption down to 0.01 mag., or 1%).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26132165','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26132165"><span id="translatedtitle">Using a Novel <span class="hlt">Absolute</span> Ontogenetic Age Determination Technique to Calculate the <span class="hlt">Timing</span> of Tooth Eruption in the Saber-Toothed Cat, Smilodon fatalis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wysocki, M Aleksander; Feranec, Robert S; Tseng, Zhijie Jack; Bjornsson, Christopher S</p> <p>2015-01-01</p> <p>Despite the superb fossil record of the saber-toothed cat, Smilodon fatalis, ontogenetic age determination for this and other ancient species remains a challenge. The present study utilizes a new technique, a combination of data from stable oxygen isotope analyses and micro-computed tomography, to establish the eruption rate for the permanent upper canines in Smilodon fatalis. The results imply an eruption rate of 6.0 millimeters per month, which is similar to a previously published average enamel growth rate of the S. fatalis upper canines (5.8 millimeters per month). Utilizing the upper canine growth rate, the upper canine eruption rate, and a previously published tooth replacement sequence, this study calculates <span class="hlt">absolute</span> ontogenetic age ranges of tooth development and eruption in S. fatalis. The <span class="hlt">timing</span> of tooth eruption is compared between S. fatalis and several extant conical-toothed felids, such as the African lion (Panthera leo). Results suggest that the permanent dentition of S. fatalis, except for the upper canines, was fully erupted by 14 to 22 months, and that the upper canines finished erupting at about 34 to 41 months. Based on these developmental age calculations, S. fatalis individuals less than 4 to 7 months of age were not typically preserved at Rancho La Brea. On the whole, S. fatalis appears to have had delayed dental development compared to dental development in similar-sized extant felids. This technique for <span class="hlt">absolute</span> ontogenetic age determination can be replicated in other ancient species, including non-saber-toothed taxa, as long as the <span class="hlt">timing</span> of growth initiation and growth rate can be determined for a specific feature, such as a tooth, and that growth period overlaps with the development of the other features under investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4489498','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4489498"><span id="translatedtitle">Using a Novel <span class="hlt">Absolute</span> Ontogenetic Age Determination Technique to Calculate the <span class="hlt">Timing</span> of Tooth Eruption in the Saber-Toothed Cat, Smilodon fatalis</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wysocki, M. Aleksander; Feranec, Robert S.; Tseng, Zhijie Jack; Bjornsson, Christopher S.</p> <p>2015-01-01</p> <p>Despite the superb fossil record of the saber-toothed cat, Smilodon fatalis, ontogenetic age determination for this and other ancient species remains a challenge. The present study utilizes a new technique, a combination of data from stable oxygen isotope analyses and micro-computed tomography, to establish the eruption rate for the permanent upper canines in Smilodon fatalis. The results imply an eruption rate of 6.0 millimeters per month, which is similar to a previously published average enamel growth rate of the S. fatalis upper canines (5.8 millimeters per month). Utilizing the upper canine growth rate, the upper canine eruption rate, and a previously published tooth replacement sequence, this study calculates <span class="hlt">absolute</span> ontogenetic age ranges of tooth development and eruption in S. fatalis. The <span class="hlt">timing</span> of tooth eruption is compared between S. fatalis and several extant conical-toothed felids, such as the African lion (Panthera leo). Results suggest that the permanent dentition of S. fatalis, except for the upper canines, was fully erupted by 14 to 22 months, and that the upper canines finished erupting at about 34 to 41 months. Based on these developmental age calculations, S. fatalis individuals less than 4 to 7 months of age were not typically preserved at Rancho La Brea. On the whole, S. fatalis appears to have had delayed dental development compared to dental development in similar-sized extant felids. This technique for <span class="hlt">absolute</span> ontogenetic age determination can be replicated in other ancient species, including non-saber-toothed taxa, as long as the <span class="hlt">timing</span> of growth initiation and growth rate can be determined for a specific feature, such as a tooth, and that growth period overlaps with the development of the other features under investigation. PMID:26132165</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27039281','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27039281"><span id="translatedtitle">Lunch-<span class="hlt">time</span> food choices in preschoolers: Relationships between <span class="hlt">absolute</span> and relative intakes of different food categories, and appetitive characteristics and weight.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Carnell, S; Pryor, K; Mais, L A; Warkentin, S; Benson, L; Cheng, R</p> <p>2016-08-01</p> <p>Children's appetitive characteristics measured by parent-report questionnaires are reliably associated with body weight, as well as behavioral tests of appetite, but relatively little is known about relationships with food choice. As part of a larger preloading study, we served 4-5year olds from primary school classes five school lunches at which they were presented with the same standardized multi-item meal. Parents completed Child Eating Behavior Questionnaire (CEBQ) sub-scales assessing satiety responsiveness (CEBQ-SR), food responsiveness (CEBQ-FR) and enjoyment of food (CEBQ-EF), and children were weighed and measured. Despite differing preload conditions, children showed remarkable consistency of intake patterns across all five meals with day-to-day intra-class correlations in <span class="hlt">absolute</span> and percentage intake of each food category ranging from 0.78 to 0.91. Higher CEBQ-SR was associated with lower mean intake of all food categories across all five meals, with the weakest association apparent for snack foods. Higher CEBQ-FR was associated with higher intake of white bread and fruits and vegetables, and higher CEBQ-EF was associated with greater intake of all categories, with the strongest association apparent for white bread. Analyses of intake of each food group as a percentage of total intake, treated here as an index of the child's choice to consume relatively more or relatively less of each different food category when composing their total lunch-<span class="hlt">time</span> meal, further suggested that children who were higher in CEBQ-SR ate relatively more snack foods and relatively less fruits and vegetables, while children with higher CEBQ-EF ate relatively less snack foods and relatively more white bread. Higher <span class="hlt">absolute</span> intakes of white bread and snack foods were associated with higher BMI z score. CEBQ sub-scale associations with food intake variables were largely unchanged by controlling for daily metabolic needs. However, descriptive comparisons of lunch intakes with</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/9183178','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/9183178"><span id="translatedtitle">Functional wave <span class="hlt">time</span>-lag focusing matrix-assisted laser desorption/ionization in a linear <span class="hlt">time</span>-of-flight mass spectrometer: improved mass <span class="hlt">accuracy</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Whittal, R M; Russon, L M; Weinberger, S R; Li, L</p> <p>1997-06-01</p> <p>A strength of matrix-assisted laser desorption/ionization (MALDI) mass spectrometry is its ability to analyze mixtures without separation. MALDI mass spectrometers capable of providing a linear mass calibration over a broad mass range should find wide use in these applications. This work addresses issues pertinent to mass measurement <span class="hlt">accuracy</span> of a <span class="hlt">time</span>-lag focusing MALDI <span class="hlt">time</span>-of-flight instrument and presents a new approach to improving mass <span class="hlt">accuracy</span> by using a functional wave extraction pulse, instead of a square wave, for <span class="hlt">time</span>-lag focusing. A model is described of an ideal extraction pulse shape that provides constant total kinetic energy for all ions. If total kinetic energy is constant, then there is an exact linear correlation between ion mass and flight <span class="hlt">time</span> raised to the second power. Using a descending wave extraction pulse, it is demonstrated that mass <span class="hlt">accuracy</span> of better than 30 ppm using two internal calibrants and better than 70 ppm using external calibrants can be obtained over a 25 ku mass range. The practical aspects of an instrument needed to obtain consistent mass <span class="hlt">accuracy</span> is discussed. It is found that ion flight <span class="hlt">time</span> shows a small dependence upon laser flux; flight <span class="hlt">times</span> increase slightly as the flux increases. But this dependence is much smaller than is observed in continuous-extraction MALDI.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://medlineplus.gov/ency/article/003649.htm','NIH-MEDLINEPLUS'); return false;" href="https://medlineplus.gov/ency/article/003649.htm"><span id="translatedtitle">Eosinophil count - <span class="hlt">absolute</span></span></a></p> <p><a target="_blank" href="http://medlineplus.gov/">MedlinePlus</a></p> <p></p> <p></p> <p>Eosinophils; <span class="hlt">Absolute</span> eosinophil count ... the white blood cell count to give the <span class="hlt">absolute</span> eosinophil count. ... than 500 cells per microliter (cells/mcL). Normal value ranges may vary slightly among different laboratories. Talk ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160004689','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160004689"><span id="translatedtitle">Assessing and Ensuring GOES-R Magnetometer <span class="hlt">Accuracy</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kronenwetter, Jeffrey; Carter, Delano R.; Todirita, Monica; Chu, Donald</p> <p>2016-01-01</p> <p>The GOES-R magnetometer <span class="hlt">accuracy</span> requirement is 1.7 nanoteslas (nT). During quiet <span class="hlt">times</span> (100 nT), <span class="hlt">accuracy</span> is defined as <span class="hlt">absolute</span> mean plus 3 sigma. During storms (300 nT), <span class="hlt">accuracy</span> is defined as <span class="hlt">absolute</span> mean plus 2 sigma. To achieve this, the sensor itself has better than 1 nT <span class="hlt">accuracy</span>. Because zero offset and scale factor drift over <span class="hlt">time</span>, it is also necessary to perform annual calibration maneuvers. To predict performance, we used covariance analysis and attempted to corroborate it with simulations. Although not perfect, the two generally agree and show the expected behaviors. With the annual calibration regimen, these predictions suggest that the magnetometers will meet their <span class="hlt">accuracy</span> requirements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160004691','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160004691"><span id="translatedtitle">Assessing and Ensuring GOES-R Magnetometer <span class="hlt">Accuracy</span></span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Carter, Delano R.; Todirita, Monica; Kronenwetter, Jeffrey; Chu, Donald</p> <p>2016-01-01</p> <p>The GOES-R magnetometer subsystem <span class="hlt">accuracy</span> requirement is 1.7 nanoteslas (nT). During quiet <span class="hlt">times</span> (100 nT), <span class="hlt">accuracy</span> is defined as <span class="hlt">absolute</span> mean plus 3 sigma. During storms (300 nT), <span class="hlt">accuracy</span> is defined as <span class="hlt">absolute</span> mean plus 2 sigma. Error comes both from outside the magnetometers, e.g. spacecraft fields and misalignments, as well as inside, e.g. zero offset and scale factor errors. Because zero offset and scale factor drift over <span class="hlt">time</span>, it will be necessary to perform annual calibration maneuvers. To predict performance before launch, we have used Monte Carlo simulations and covariance analysis. Both behave as expected, and their <span class="hlt">accuracy</span> predictions agree within 30%. With the proposed calibration regimen, both suggest that the GOES-R magnetometer subsystem will meet its <span class="hlt">accuracy</span> requirements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=5S&pg=4&id=EJ734761','ERIC'); return false;" href="http://eric.ed.gov/?q=5S&pg=4&id=EJ734761"><span id="translatedtitle">The Effects of Spatial Stimulus-Response Compatibility on Choice <span class="hlt">Time</span> Production <span class="hlt">Accuracy</span> and Variability</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Rakitin, Brian C.</p> <p>2005-01-01</p> <p>Five experiments examined the relations between <span class="hlt">timing</span> and attention using a choice <span class="hlt">time</span> production task in which the latency of a spatial choice response is matched to a target interval (3 or 5 s). Experiments 1 and 2 indicated that spatial stimulus-response incompatibility increased nonscalar <span class="hlt">timing</span> variability without affecting <span class="hlt">timing</span> accuracy…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26737821','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26737821"><span id="translatedtitle">Estimation of the reaction <span class="hlt">times</span> in tasks of varying difficulty from the phase coherence of the auditory steady-state response using the least <span class="hlt">absolute</span> shrinkage and selection operator analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yokota, Yusuke; Igarashi, Yasuhiko; Okada, Masato; Naruse, Yasushi</p> <p>2015-01-01</p> <p>Quantitative estimation of the workload in the brain is an important factor for helping to predict the behavior of humans. The reaction <span class="hlt">time</span> when performing a difficult task is longer than that when performing an easy task. Thus, the reaction <span class="hlt">time</span> reflects the workload in the brain. In this study, we employed an N-back task in order to regulate the degree of difficulty of the tasks, and then estimated the reaction <span class="hlt">times</span> from the brain activity. The brain activity that we used to estimate the reaction <span class="hlt">time</span> was the auditory steady-state response (ASSR) evoked by a 40-Hz click sound. Fifteen healthy participants participated in the present study and magnetoencephalogram (MEG) responses were recorded using a 148-channel magnetometer system. The least <span class="hlt">absolute</span> shrinkage and selection operator (LASSO), which is a type of sparse modeling, was employed to estimate the reaction <span class="hlt">times</span> from the ASSR recorded by MEG. The LASSO showed higher estimation <span class="hlt">accuracy</span> than the least squares method. This result indicates that LASSO overcame the over-fitting to the learning data. Furthermore, the LASSO selected channels in not only the parietal region, but also in the frontal and occipital regions. Since the ASSR is evoked by auditory stimuli, it is usually large in the parietal region. However, since LASSO also selected channels in regions outside the parietal region, this suggests that workload-related neural activity occurs in many brain regions. In the real world, it is more practical to use a wearable electroencephalography device with a limited number of channels than to use MEG. Therefore, determining which brain areas should be measured is essential. The channels selected by the sparse modeling method are informative for determining which brain areas to measure. PMID:26737821</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23287833','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23287833"><span id="translatedtitle">The <span class="hlt">accuracy</span> of simulated indoor <span class="hlt">time</span> trials utilizing a CompuTrainer and GPS data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Peveler, Willard W</p> <p>2013-10-01</p> <p>The CompuTrainer is commonly used to measure cycling <span class="hlt">time</span> trial performance in a laboratory setting. Previous research has demonstrated that the CompuTrainer tends toward underestimating power at higher workloads but provides reliable measures. The extent to which the CompuTrainer is capable of simulating outdoor <span class="hlt">time</span> trials in a laboratory setting has yet to be examined. The purpose of this study was to examine the validity of replicating an outdoor <span class="hlt">time</span> trial course indoors by comparing completion <span class="hlt">times</span> between the actual <span class="hlt">time</span> trial course and the replicated outdoor <span class="hlt">time</span> trial course on the CompuTrainer. A global positioning system was used to collect data points along a local outdoor <span class="hlt">time</span> trial course. Data were then downloaded and converted into a <span class="hlt">time</span> trial course for the CompuTrainer. Eleven recreational to highly trained cyclists participated in this study. To participate in this study, subjects had to have completed a minimum of 2 of the local Cleves <span class="hlt">time</span> trial races. Subjects completed 2 simulated indoor <span class="hlt">time</span> trials on the CompuTrainer. Mean finishing <span class="hlt">times</span> for the mean indoor performance trial (34.58 ± 8.63 minutes) were significantly slower in relation to the mean outdoor performance <span class="hlt">time</span> (26.24 ± 3.23 minutes). Cyclists' finish <span class="hlt">times</span> increased (performance decreased) by 24% on the indoor <span class="hlt">time</span> trials in relation to the mean outdoor <span class="hlt">times</span>. There were no significant differences between CompuTrainer trial 1 (34.77 ± 8.54 minutes) and CompuTrainer trial 1 (34.37 ± 8.76 minutes). Because of the significant differences in <span class="hlt">times</span> between the indoor and outdoor <span class="hlt">time</span> trials, meaningful comparisons of performance <span class="hlt">times</span> cannot be made between the two. However, there were no significant differences found between the 2 CompuTrainer trials, and therefore the CompuTrainer can still be recommended for laboratory testing between trials.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011AGUFMSA41A1834M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011AGUFMSA41A1834M&link_type=ABSTRACT"><span id="translatedtitle"><span class="hlt">Absolute</span> Populations of Highly Vibrationally Excited OH(υ=8 + υ=9) in the Night Mesopause Region Derived from the <span class="hlt">TIMED</span>/SABER Instrument from 2002 to 2010</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mast, J. C.; Mlynczak, M. G.; Marshall, B. T.; Thompson, R. E.; Mertens, C. J.; Hunt, L. A.; Russell, J. M.; Gordley, L. L.</p> <p>2011-12-01</p> <p>We present global distributions of v = 9 + v = 8 nighttime vibrationally excited hydroxyl concentrations as measured by the SABER instrument on board the <span class="hlt">TIMED</span> spacecraft. These states are formed directly by the reaction of atomic hydrogen and ozone in the terrestrial mesopause region. SABER measures the limb radiance from the delta-v = 2 transitions in a channel centered near 2.0 um, specifically the sum of the 9 -> 7 and 8 -> 6 transitions. The limb radiances are inverted to yield the volume emission rates from the sum of the v = 8 and 9 states of the hydroxyl molecule. The Einstein coefficients for spontaneous emission for these two transitions are essentially identical. Thus dividing the derived volume emission rate by the Einstein coefficient yields the <span class="hlt">absolute</span> populations of these states (molecules per cubic cm). Nine full years of data are presented in this paper. Over this <span class="hlt">time</span> the globally averaged OH(v = 8 + v = 9) populations have varied relative to the nine year mean by only a few percent. We conclude that despite substantial solar variability over this <span class="hlt">time</span> period, the apparently small variation of the highly vibrationally excited hydroxyl populations implies that atomic hydrogen, atomic oxygen, temperature, and density adjust in such a way so as to keep the product of the atomic hydrogen concentration, the ozone concentration, and the rate coefficient for their reaction essentially constant.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21611867','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21611867"><span id="translatedtitle"><span class="hlt">Absolute</span> neutrino mass measurements</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wolf, Joachim</p> <p>2011-10-06</p> <p>The neutrino mass plays an important role in particle physics, astrophysics and cosmology. In recent years the detection of neutrino flavour oscillations proved that neutrinos carry mass. However, oscillation experiments are only sensitive to the mass-squared difference of the mass eigenvalues. In contrast to cosmological observations and neutrino-less double beta decay (0v2{beta}) searches, single {beta}-decay experiments provide a direct, model-independent way to determine the <span class="hlt">absolute</span> neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high <span class="hlt">accuracy</span>.Currently the best kinematic upper limits on the neutrino mass of 2.2eV have been set by two experiments in Mainz and Troitsk, using tritium as beta emitter. The next generation tritium {beta}-experiment KATRIN is currently under construction in Karlsruhe/Germany by an international collaboration. KATRIN intends to improve the sensitivity by one order of magnitude to 0.2eV. The investigation of a second isotope ({sup 137}Rh) is being pursued by the international MARE collaboration using micro-calorimeters to measure the beta spectrum. The technology needed to reach 0.2eV sensitivity is still in the R and D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2{beta} decay and single {beta}-decay.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19900039320&hterms=Standards+laboratory&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DStandards%2Blaboratory','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19900039320&hterms=Standards+laboratory&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3DStandards%2Blaboratory"><span id="translatedtitle">Cryogenic <span class="hlt">absolute</span> radiometers as laboratory irradiance standards, remote sensing detectors, and pyroheliometers</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Foukal, Peter V.; Hoyt, C.; Kochling, H.; Miller, P.</p> <p>1990-01-01</p> <p>The dramatic improvement in heat diffusivity of pure Cu at liquid-He temperatures makes possible very important advances in the <span class="hlt">absolute</span> <span class="hlt">accuracy</span>, reproducibility, sensitivity, and <span class="hlt">time</span> constant of cryogenic electrical substitution radiometers (ESRs), relative to conventional ESRs. The design and characterization of a table-top cryogenic ESR now available for detector calibration work to the 0.01-percent level of <span class="hlt">absolute</span> <span class="hlt">accuracy</span> under laser illumination is discussed. A sensitive cryogenic ESR recently delivered to the NIST for radiometric calibrations of black bodies is also described, along with the design and testing of a very fast cryogenic ESR developed for NASA remote-sensing studies of the earth's radiation budget.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22792243','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22792243"><span id="translatedtitle">Climatic associations of British species distributions show good transferability in <span class="hlt">time</span> but low predictive <span class="hlt">accuracy</span> for range change.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rapacciuolo, Giovanni; Roy, David B; Gillings, Simon; Fox, Richard; Walker, Kevin; Purvis, Andy</p> <p>2012-01-01</p> <p>Conservation planners often wish to predict how species distributions will change in response to environmental changes. Species distribution models (SDMs) are the primary tool for making such predictions. Many methods are widely used; however, they all make simplifying assumptions, and predictions can therefore be subject to high uncertainty. With global change well underway, field records of observed range shifts are increasingly being used for testing SDM transferability. We used an unprecedented distribution dataset documenting recent range changes of British vascular plants, birds, and butterflies to test whether correlative SDMs based on climate change provide useful approximations of potential distribution shifts. We modelled past species distributions from climate using nine single techniques and a consensus approach, and projected the geographical extent of these models to a more recent <span class="hlt">time</span> period based on climate change; we then compared model predictions with recent observed distributions in order to estimate the temporal transferability and prediction <span class="hlt">accuracy</span> of our models. We also evaluated the relative effect of methodological and taxonomic variation on the performance of SDMs. Models showed good transferability in <span class="hlt">time</span> when assessed using widespread metrics of <span class="hlt">accuracy</span>. However, models had low <span class="hlt">accuracy</span> to predict where occupancy status changed between <span class="hlt">time</span> periods, especially for declining species. Model performance varied greatly among species within major taxa, but there was also considerable variation among modelling frameworks. Past climatic associations of British species distributions retain a high explanatory power when transferred to recent <span class="hlt">time</span>--due to their <span class="hlt">accuracy</span> to predict large areas retained by species--but fail to capture relevant predictors of change. We strongly emphasize the need for caution when using SDMs to predict shifts in species distributions: high explanatory power on temporally-independent records--as assessed using</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/976087','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/976087"><span id="translatedtitle">Unstructured grids in 3D and 4D for a <span class="hlt">time</span>-dependent interface in front tracking with improved <span class="hlt">accuracy</span></span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Glimm, J.; Grove, J. W.; Li, X. L.; Li, Y.; Xu, Z.</p> <p>2002-01-01</p> <p>Front tracking traces the dynamic evolution of an interface separating differnt materials or fluid components. In this paper, they describe three types of the grid generation methods used in the front tracking method. One is the unstructured surface grid. The second is a structured grid-based reconstruction method. The third is a <span class="hlt">time</span>-space grid, also grid based, for a conservative tracking algorithm with improved <span class="hlt">accuracy</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3746027','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3746027"><span id="translatedtitle"><span class="hlt">Accuracy</span> of a Mitral Valve Segmentation Method Using J-Splines for Real-<span class="hlt">Time</span> 3D Echocardiography Data</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Siefert, Andrew W.; Icenogle, David A.; Rabbah, Jean-Pierre; Saikrishnan, Neelakantan; Rossignac, Jarek; Lerakis, Stamatios; Yoganathan, Ajit P.</p> <p>2013-01-01</p> <p>Patient-specific models of the heart’s mitral valve (MV) exhibit potential for surgical planning. While advances in 3D echocardiography (3DE) have provided adequate resolution to extract MV leaflet geometry, no study has quantitatively assessed the <span class="hlt">accuracy</span> of their modeled leaflets versus a ground-truth standard for temporal frames beyond systolic closure or for differing valvular dysfunctions. The <span class="hlt">accuracy</span> of a 3DE-based segmentation methodology based on J-splines was assessed for porcine MVs with known 4D leaflet coordinates within a pulsatile simulator during closure, peak closure, and opening for a control, prolapsed, and billowing MV model. For all <span class="hlt">time</span> points, the mean distance error between the segmented models and ground-truth data were 0.40±0.32 mm, 0.52±0.51 mm, and 0.74±0.69 mm for the control, flail, and billowing models. For all models and temporal frames, 95% of the distance errors were below 1.64 mm. When applied to a patient data set, segmentation was able to confirm a regurgitant orifice and post-operative improvements in coaptation. This study provides an experimental platform for assessing the <span class="hlt">accuracy</span> of an MV segmentation methodology at phases beyond systolic closure and for differing MV dysfunctions. Results demonstrate the <span class="hlt">accuracy</span> of a MV segmentation methodology for the development of future surgical planning tools. PMID:23460042</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=markov-chain+AND+monte-carlo+AND+analysis&pg=2&id=EJ1015250','ERIC'); return false;" href="http://eric.ed.gov/?q=markov-chain+AND+monte-carlo+AND+analysis&pg=2&id=EJ1015250"><span id="translatedtitle">A Semiparametric Model for Jointly Analyzing Response <span class="hlt">Times</span> and <span class="hlt">Accuracy</span> in Computerized Testing</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Wang, Chun; Fan, Zhewen; Chang, Hua-Hua; Douglas, Jeffrey A.</p> <p>2013-01-01</p> <p>The item response <span class="hlt">times</span> (RTs) collected from computerized testing represent an underutilized type of information about items and examinees. In addition to knowing the examinees' responses to each item, we can investigate the amount of <span class="hlt">time</span> examinees spend on each item. Current models for RTs mainly focus on parametric models, which have the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27007339','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27007339"><span id="translatedtitle">Effect of <span class="hlt">Time</span> Lapse on the Diagnostic <span class="hlt">Accuracy</span> of Cone Beam Computed Tomography for Detection of Vertical Root Fractures.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Eskandarloo, Amir; Asl, Amin Mahdavi; Jalalzadeh, Mohsen; Tayari, Maryam; Hosseinipanah, Mohammad; Fardmal, Javad; Shokri, Abbas</p> <p>2016-01-01</p> <p>Accurate and early diagnosis of vertical root fractures (VRFs) is imperative to prevent extensive bone loss and unnecessary endodontic and prosthodontic treatments. The aim of this study was to assess the effect of <span class="hlt">time</span> lapse on the diagnostic <span class="hlt">accuracy</span> of cone beam computed tomography (CBCT) for VRFs in endodontically treated dog's teeth. Forty-eight incisors and premolars of three adult male dogs underwent root canal therapy. The teeth were assigned to two groups: VRFs were artificially induced in the first group (n=24) while the teeth in the second group remained intact (n=24). The CBCT scans were obtained by NewTom 3G unit immediately after inducing VRFs and after one, two, three, four, eight, 12 and 16 weeks. Three oral and maxillofacial radiologists blinded to the date of radiographs assessed the presence/absence of VRFs on CBCT scans. The sensitivity, specificity and <span class="hlt">accuracy</span> values were calculated and data were analyzed using SPSS v.16 software and ANOVA. The total <span class="hlt">accuracy</span> of detection of VRFs immediately after surgery, one, two, three, four, eight, 12 and 16 weeks was 67.3%, 68.7%, 66.6%, 64.6%, 64.5%, 69.4%, 68.7%, 68% respectively. The effect of <span class="hlt">time</span> lapse on detection of VRFs was not significant (p>0.05). Overall sensitivity, specificity and <span class="hlt">accuracy</span> of CBCT for detection of VRFs were 74.3%, 62.2%, 67.2% respectively. Cone beam computed tomography is a valuable tool for detection of VRFs. <span class="hlt">Time</span> lapse (four months) had no effect on detection of VRFs on CBCT scans. PMID:27007339</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_9");'>9</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li class="active"><span>11</span></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_11 --> <div id="page_12" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="221"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27007339','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27007339"><span id="translatedtitle">Effect of <span class="hlt">Time</span> Lapse on the Diagnostic <span class="hlt">Accuracy</span> of Cone Beam Computed Tomography for Detection of Vertical Root Fractures.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Eskandarloo, Amir; Asl, Amin Mahdavi; Jalalzadeh, Mohsen; Tayari, Maryam; Hosseinipanah, Mohammad; Fardmal, Javad; Shokri, Abbas</p> <p>2016-01-01</p> <p>Accurate and early diagnosis of vertical root fractures (VRFs) is imperative to prevent extensive bone loss and unnecessary endodontic and prosthodontic treatments. The aim of this study was to assess the effect of <span class="hlt">time</span> lapse on the diagnostic <span class="hlt">accuracy</span> of cone beam computed tomography (CBCT) for VRFs in endodontically treated dog's teeth. Forty-eight incisors and premolars of three adult male dogs underwent root canal therapy. The teeth were assigned to two groups: VRFs were artificially induced in the first group (n=24) while the teeth in the second group remained intact (n=24). The CBCT scans were obtained by NewTom 3G unit immediately after inducing VRFs and after one, two, three, four, eight, 12 and 16 weeks. Three oral and maxillofacial radiologists blinded to the date of radiographs assessed the presence/absence of VRFs on CBCT scans. The sensitivity, specificity and <span class="hlt">accuracy</span> values were calculated and data were analyzed using SPSS v.16 software and ANOVA. The total <span class="hlt">accuracy</span> of detection of VRFs immediately after surgery, one, two, three, four, eight, 12 and 16 weeks was 67.3%, 68.7%, 66.6%, 64.6%, 64.5%, 69.4%, 68.7%, 68% respectively. The effect of <span class="hlt">time</span> lapse on detection of VRFs was not significant (p>0.05). Overall sensitivity, specificity and <span class="hlt">accuracy</span> of CBCT for detection of VRFs were 74.3%, 62.2%, 67.2% respectively. Cone beam computed tomography is a valuable tool for detection of VRFs. <span class="hlt">Time</span> lapse (four months) had no effect on detection of VRFs on CBCT scans.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3412274','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3412274"><span id="translatedtitle">Precise and Continuous <span class="hlt">Time</span> and Frequency Synchronisation at the 5×10-19 <span class="hlt">Accuracy</span> Level</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Wang, B.; Gao, C.; Chen, W. L.; Miao, J.; Zhu, X.; Bai, Y.; Zhang, J. W.; Feng, Y. Y.; Li, T. C.; Wang, L. J.</p> <p>2012-01-01</p> <p>The synchronisation of <span class="hlt">time</span> and frequency between remote locations is crucial for many important applications. Conventional <span class="hlt">time</span> and frequency dissemination often makes use of satellite links. Recently, the communication fibre network has become an attractive option for long-distance <span class="hlt">time</span> and frequency dissemination. Here, we demonstrate accurate frequency transfer and <span class="hlt">time</span> synchronisation via an 80 km fibre link between Tsinghua University (THU) and the National Institute of Metrology of China (NIM). Using a 9.1 GHz microwave modulation and a <span class="hlt">timing</span> signal carried by two continuous-wave lasers and transferred across the same 80 km urban fibre link, frequency transfer stability at the level of 5×10−19/day was achieved. <span class="hlt">Time</span> synchronisation at the 50 ps precision level was also demonstrated. The system is reliable and has operated continuously for several months. We further discuss the feasibility of using such frequency and <span class="hlt">time</span> transfer over 1000 km and its applications to long-baseline radio astronomy. PMID:22870385</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3654687','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3654687"><span id="translatedtitle">Association Between <span class="hlt">Time</span> Spent Interpreting, Level of Confidence and <span class="hlt">Accuracy</span> of Screening Mammography</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Carney, Patricia A.; Bogart, Andy; Geller, Berta M.; Haneuse, Sebastian; Kerlikowske, Karla; Buist, Diana SM; Smith, Robert; Rosenberg, Robert; Yankaskas, Bonnie C.; Onega, Tracy; Miglioretti, Diana L.</p> <p>2013-01-01</p> <p>Purpose To examine the effect of <span class="hlt">time</span> spent viewing images and level of confidence on a screening mammography test set on interpretive performance. Materials and Methods Radiologists from six mammography registries participated in the study and were randomized to interpret one of four test sets and complete 12 survey questions. Each test set had 109 cases of digitized four-view screening film-screen mammograms with prior comparison screening views. Viewing <span class="hlt">time</span> for each case was defined as the cumulative <span class="hlt">time</span> spent viewing all mammographic images before recording which visible feature, if any, was the “most significant finding”. Log-linear regression fit via GEE was used to test the effect of viewing <span class="hlt">time</span> and level of confidence in the interpretation on test set sensitivity and false-positive rate. Results 119 radiologists completed a test set and contributed data on 11,484 interpretations. Radiologists spent more <span class="hlt">time</span> viewing cases that had significant findings or for which they had less confidence in interpretation. Each additional minute of viewing <span class="hlt">time</span> increased the probability of a true positive interpretation among cancer cases by 1.12 (95% CI: 1.06, 1.19, p<0.001), regardless of confidence in the assessment. Among radiologists who were ‘very confident’ in their assessment, each additional minute of viewing <span class="hlt">time</span> increased the adjusted risk of a false positive interpretation among non-cancer cases by 1.42 (95% CI 1.21, 1.68), and this viewing-<span class="hlt">time</span> effect diminished with decreasing confidence. Conclusions Longer interpretation <span class="hlt">times</span> and higher levels of confidence in the interpretation are both associated with higher sensitivity and false positive rates in mammography screening. PMID:22451568</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013SPIE.9046E..1DY','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013SPIE.9046E..1DY"><span id="translatedtitle"><span class="hlt">Accuracy</span> study of <span class="hlt">time</span> delay estimation techniques in laser pulse ranger</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Jinliang; Wang, Xingshu; Gao, Yang</p> <p>2013-12-01</p> <p><span class="hlt">Time</span>-of-flight measurement by using laser pulses is an alternative method in laser range finding and laser scanning, the echo pulses originating from backscattering of the emitted laser pulse on targets is detected by optical receiver. The distance of target can be obtained by measuring the round-trip <span class="hlt">time</span>. <span class="hlt">Time</span>-of-arrival estimation may be based on schemes such as constant-fraction discriminator (CFD) in analog electronics. In contrast, as sampled signals are available, <span class="hlt">time</span> delay estimation may be based on schemes like direct cross-correlation function (CCF) and average square difference function (ASDF) in digital electronics. By the way, constant-fraction discriminator can also be used in digital electronics. All this three methods are analyzed and compared with each other. It is shown that estimators based on CCF and ASDF are more precise than conventional CFD based estimator.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21084736','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21084736"><span id="translatedtitle">Two- and three-dimensional <span class="hlt">accuracy</span> of dental impression materials: effects of storage <span class="hlt">time</span> and moisture contamination.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chandran, Deepa T; Jagger, Daryll C; Jagger, Robert G; Barbour, Michele E</p> <p>2010-01-01</p> <p>Dental impression materials are used to create an inverse replica of the dental hard and soft tissues, and are used in processes such as the fabrication of crowns and bridges. The <span class="hlt">accuracy</span> and dimensional stability of impression materials are of paramount importance to the <span class="hlt">accuracy</span> of fit of the resultant prosthesis. Conventional methods for assessing the dimensional stability of impression materials are two-dimensional (2D), and assess shrinkage or expansion between selected fixed points on the impression. In this study, dimensional changes in four impression materials were assessed using an established 2D and an experimental three-dimensional (3D) technique. The former involved measurement of the distance between reference points on the impression; the latter a contact scanning method for producing a computer map of the impression surface showing localised expansion, contraction and warpage. Dimensional changes were assessed as a function of storage <span class="hlt">times</span> and moisture contamination comparable to that found in clinical situations. It was evident that dimensional changes observed using the 3D technique were not always apparent using the 2D technique, and that the former offers certain advantages in terms of assessing dimensional <span class="hlt">accuracy</span> and predictability of impression methods. There are, however, drawbacks associated with 3D techniques such as the more <span class="hlt">time</span>-consuming nature of the data acquisition and difficulty in statistically analysing the data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23409592','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23409592"><span id="translatedtitle">Movement imagery for speech in healthy women: influences on articulation <span class="hlt">accuracy</span> and fluidity, imagery <span class="hlt">times</span>, and expectations of success.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mantie-Kozlowski, Alana; Netsell, Ronald; Daniel, Todd</p> <p>2012-12-01</p> <p>The use of movement imagery in speech performance has received less attention than it has in many other professional disciplines. 30 healthy monolingual native English speakers participated in this within-subjects study. Participants' speech <span class="hlt">accuracy</span> and fluidity was compared when they used movement imagery and when they did not. The <span class="hlt">timing</span> of imagery and articulation were compared using a chronometric paradigm. Participants' expectations of improvement when using movement imagery for speech were compared to their actual performance. The results from this study support the use of movement imagery for speech with a single imaging event for the purpose of improving speech fluidity, but not for improving articulation <span class="hlt">accuracy</span>. The chronometric system as a tool for monitoring adherence to the movement imagery protocol for speech proved valuable. Finally, while estimation inflation has been reported by some using movement imagery techniques, this was not the case for the participants of this study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012SPIE.8441E..1FS&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012SPIE.8441E..1FS&link_type=ABSTRACT"><span id="translatedtitle">A novel mask proximity correction software combining <span class="hlt">accuracy</span> and reduced writing <span class="hlt">time</span> for the manufacturing of advanced photomasks</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schiavone, Patrick; Martin, Luc; Browning, Clyde; Farys, Vincent; Sundermann, Frank; Narukawa, Shogo; Takikawa, Tadahiko; Hayashi, Naoya</p> <p>2012-06-01</p> <p>The new generations of photomasks are seen to bring more and more challenges to the mask manufacturer. Maskshops face two conflicting requirements, namely improving pattern fidelity and reducing or at least maintaining acceptable writing <span class="hlt">time</span>. These requirements are getting more and more challenging since pattern size continuously shrinks and data volumes continuously grows. Although the classical dose modulation Proximity Effect Correction is able to provide sufficient process control to the mainstream products, an increased number of published and wafer data show that the mask process is becoming a nonnegligible contributor to the 28nm technology yield. We will show in this paper that a novel approach of mask proximity effect correction is able to meet the dual challenge of the new generation of masks. Unlike the classical approach, the technique presented in this paper is based on a concurrent optimization of the dose and geometry of the fractured shots. Adding one more parameter allows providing the best possible compromise between <span class="hlt">accuracy</span> and writing <span class="hlt">time</span> since energy latitude can be taken into account as well. This solution is implemented in the Inscale software package from Aselta Nanographics. We have assessed the capability of this technology on several levels of a 28nm technology. On this set, the writing <span class="hlt">time</span> has been reduced up to 25% without sacrificing the <span class="hlt">accuracy</span> which at the same <span class="hlt">time</span> has been improved significantly compared to the existing process. The experiments presented in the paper confirm that a versatile proximity effect correction strategy, combining dose and geometry modulation helps the users to tradeoff between resolution/<span class="hlt">accuracy</span> and e-beam write <span class="hlt">time</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4147194','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4147194"><span id="translatedtitle">Reduced temporal sampling effect on <span class="hlt">accuracy</span> of <span class="hlt">time</span>-domain fluorescence lifetime Förster resonance energy transfer</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Omer, Travis; Zhao, Lingling; Intes, Xavier; Hahn, Juergen</p> <p>2014-01-01</p> <p>Abstract. Fluorescence lifetime imaging (FLIM) aims at quantifying the exponential decay rate of fluorophores to yield lifetime maps over the imaged sample. When combined with Förster resonance energy transfer (FRET), the technique can be used to indirectly sense interactions at the nanoscale such as protein–protein interactions, protein–DNA interactions, and protein conformational changes. In the case of FLIM-FRET, the fluorescence intensity decays are fitted to a biexponential model in order to estimate the lifetime and fractional amplitude coefficients of each component of the population of the donor fluorophore (quenched and nonquenched). Numerous <span class="hlt">time</span> data points, also called temporal or <span class="hlt">time</span> gates, are typically employed for accurately estimating the model parameters, leading to lengthy acquisition <span class="hlt">times</span> and significant computational demands. This work investigates the effect of the number and location of <span class="hlt">time</span> gates on model parameter estimation <span class="hlt">accuracy</span>. A detailed model of a FLIM-FRET imaging system is used for the investigation, and the simulation outcomes are validated with in vitro and in vivo experimental data. In all cases investigated, it is found that 10 equally spaced <span class="hlt">time</span> gates allow robust estimation of model-based parameters with <span class="hlt">accuracy</span> similar to that of full temporal datasets (90 gates). PMID:25166472</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23536060','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23536060"><span id="translatedtitle">Parsing the phonological loop: activation <span class="hlt">timing</span> in the dorsal speech stream determines <span class="hlt">accuracy</span> in speech reproduction.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Herman, Alexander B; Houde, John F; Vinogradov, Sophia; Nagarajan, Srikantan S</p> <p>2013-03-27</p> <p>Despite significant research and important clinical correlates, direct neural evidence for a phonological loop linking speech perception, short-term memory and production remains elusive. To investigate these processes, we acquired whole-head magnetoencephalographic (MEG) recordings from human subjects performing a variable-length syllable sequence reproduction task. The MEG sensor data were source localized using a <span class="hlt">time</span>-frequency optimized spatially adaptive filter, and we examined the <span class="hlt">time</span> courses of cortical oscillatory power and the correlations of oscillatory power with behavior between onset of the audio stimulus and the overt speech response. We found dissociations between <span class="hlt">time</span> courses of behaviorally relevant activations in a network of regions falling primarily within the dorsal speech stream. In particular, verbal working memory load modulated high gamma power in both Sylvian-parietal-temporal and Broca's areas. The <span class="hlt">time</span> courses of the correlations between high gamma power and subject performance clearly alternated between these two regions throughout the task. Our results provide the first evidence of a reverberating input-output buffer system in the dorsal stream underlying speech sensorimotor integration, consistent with recent phonological loop, competitive queuing, and speech-motor control models. These findings also shed new light on potential sources of speech dysfunction in aphasia and neuropsychiatric disorders, identifying anatomically and behaviorally dissociable activation <span class="hlt">time</span> windows critical for successful speech reproduction. PMID:23536060</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25637542','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25637542"><span id="translatedtitle"><span class="hlt">Accuracy</span> of patient's turnover <span class="hlt">time</span> prediction using RFID technology in an academic ambulatory surgery center.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Marchand-Maillet, Florence; Debes, Claire; Garnier, Fanny; Dufeu, Nicolas; Sciard, Didier; Beaussier, Marc</p> <p>2015-02-01</p> <p>Patients flow in outpatient surgical unit is a major issue with regards to resource utilization, overall case load and patient satisfaction. An electronic Radio Frequency Identification Device (RFID) was used to document the overall <span class="hlt">time</span> spent by the patients between their admission and discharge from the unit. The objective of this study was to evaluate how a RFID-based data collection system could provide an accurate prediction of the actual <span class="hlt">time</span> for the patient to be discharged from the ambulatory surgical unit after surgery. This is an observational prospective evaluation carried out in an academic ambulatory surgery center (ASC). Data on length of stay at each step of the patient care, from admission to discharge, were recorded by a RFID device and analyzed according to the type of surgical procedure, the surgeon and the anesthetic technique. Based on these initial data (n = 1520), patients were scheduled in a sequential manner according to the expected duration of the previous case. The primary endpoint was the difference between actual and predicted <span class="hlt">time</span> of discharge from the unit. A total of 414 consecutive patients were prospectively evaluated. One hundred seventy four patients (42%) were discharged at the predicted <span class="hlt">time</span> ± 30 min. Only 24% were discharged behind predicted schedule. Using an automatic record of patient's length of stay would allow an accurate prediction of the discharge <span class="hlt">time</span> according to the type of surgery, the surgeon and the anesthetic procedure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/24512176','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/24512176"><span id="translatedtitle"><span class="hlt">Accuracy</span> of an UWB-based position tracking system used for <span class="hlt">time</span>-motion analyses in game sports.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Leser, Roland; Schleindlhuber, Armin; Lyons, Keith; Baca, Arnold</p> <p>2014-01-01</p> <p>The main aim of this study was to determine the <span class="hlt">accuracy</span> of the ultra-wideband (UWB)-based positioning system Ubisense, which is used for <span class="hlt">time</span>-motion analysis in sports. Furthermore, some alternatives for positioning the system's transponders on the atheletes, as well as the <span class="hlt">accuracy</span> depending on the location of measurement, were tested. Therefore, in a pre-study, some basic issues were examined (measurement assumptions and consistency and location of the system's transponder used for position detection), and position measurements at the borders and in the centre of a basketball field were performed. In the main study, 13 male basketball players (15.8 years ± 0.6; 187.9 height ± 3.4; 77.5 weight ± 3.7), equipped with a Ubisense transponder mounted on top of their heads, handled a trundle wheel during simulated match play. The players with the trundle wheel participated passively in the match by following one of the ten competing players. The distance measurements of the trundle wheel were used as reference values and compared to the Ubisense distance estimations. Best results were found with the measurements of a single mounted transponder on top of the athlete's heads. No differences were detectable in the <span class="hlt">accuracy</span> between measurements in the centre and at the borders of the basketball field. The (Ubisense) system's difference to the (trundle wheel) reference was 3.45 ± 1.99%, resulting in 95% limits of agreement of -0.46-7.35%. The study indicates the examined system's sufficient <span class="hlt">accuracy</span> for <span class="hlt">time</span>-motion analysis in basketball. PMID:24512176</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24512176','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24512176"><span id="translatedtitle"><span class="hlt">Accuracy</span> of an UWB-based position tracking system used for <span class="hlt">time</span>-motion analyses in game sports.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Leser, Roland; Schleindlhuber, Armin; Lyons, Keith; Baca, Arnold</p> <p>2014-01-01</p> <p>The main aim of this study was to determine the <span class="hlt">accuracy</span> of the ultra-wideband (UWB)-based positioning system Ubisense, which is used for <span class="hlt">time</span>-motion analysis in sports. Furthermore, some alternatives for positioning the system's transponders on the atheletes, as well as the <span class="hlt">accuracy</span> depending on the location of measurement, were tested. Therefore, in a pre-study, some basic issues were examined (measurement assumptions and consistency and location of the system's transponder used for position detection), and position measurements at the borders and in the centre of a basketball field were performed. In the main study, 13 male basketball players (15.8 years ± 0.6; 187.9 height ± 3.4; 77.5 weight ± 3.7), equipped with a Ubisense transponder mounted on top of their heads, handled a trundle wheel during simulated match play. The players with the trundle wheel participated passively in the match by following one of the ten competing players. The distance measurements of the trundle wheel were used as reference values and compared to the Ubisense distance estimations. Best results were found with the measurements of a single mounted transponder on top of the athlete's heads. No differences were detectable in the <span class="hlt">accuracy</span> between measurements in the centre and at the borders of the basketball field. The (Ubisense) system's difference to the (trundle wheel) reference was 3.45 ± 1.99%, resulting in 95% limits of agreement of -0.46-7.35%. The study indicates the examined system's sufficient <span class="hlt">accuracy</span> for <span class="hlt">time</span>-motion analysis in basketball.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3130590','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3130590"><span id="translatedtitle">Calibration of diffuse correlation spectroscopy with a <span class="hlt">time</span>-resolved near-infrared technique to yield <span class="hlt">absolute</span> cerebral blood flow measurements</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Diop, Mamadou; Verdecchia, Kyle; Lee, Ting-Yim; St Lawrence, Keith</p> <p>2011-01-01</p> <p>A primary focus of neurointensive care is the prevention of secondary brain injury, mainly caused by ischemia. A noninvasive bedside technique for continuous monitoring of cerebral blood flow (CBF) could improve patient management by detecting ischemia before brain injury occurs. A promising technique for this purpose is diffuse correlation spectroscopy (DCS) since it can continuously monitor relative perfusion changes in deep tissue. In this study, DCS was combined with a <span class="hlt">time</span>-resolved near-infrared technique (TR-NIR) that can directly measure CBF using indocyanine green as a flow tracer. With this combination, the TR-NIR technique can be used to convert DCS data into <span class="hlt">absolute</span> CBF measurements. The agreement between the two techniques was assessed by concurrent measurements of CBF changes in piglets. A strong correlation between CBF changes measured by TR-NIR and changes in the scaled diffusion coefficient measured by DCS was observed (R2 = 0.93) with a slope of 1.05 ± 0.06 and an intercept of 6.4 ± 4.3% (mean ± standard error). PMID:21750781</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1012660','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1012660"><span id="translatedtitle">Method and computer product to increase <span class="hlt">accuracy</span> of <span class="hlt">time</span>-based software verification for sensor networks</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Foo Kune, Denis; Mahadevan, Karthikeyan</p> <p>2011-01-25</p> <p>A recursive verification protocol to reduce the <span class="hlt">time</span> variance due to delays in the network by putting the subject node at most one hop from the verifier node provides for an efficient manner to test wireless sensor nodes. Since the software signatures are <span class="hlt">time</span> based, recursive testing will give a much cleaner signal for positive verification of the software running on any one node in the sensor network. In this protocol, the main verifier checks its neighbor, who in turn checks its neighbor, and continuing this process until all nodes have been verified. This ensures minimum <span class="hlt">time</span> delays for the software verification. Should a node fail the test, the software verification downstream is halted until an alternative path (one not including the failed node) is found. Utilizing techniques well known in the art, having a node tested twice, or not at all, can be avoided.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvB..93x1118Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvB..93x1118Z"><span id="translatedtitle">Boosting the <span class="hlt">accuracy</span> and speed of quantum Monte Carlo: Size consistency and <span class="hlt">time</span> step</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zen, Andrea; Sorella, Sandro; Gillan, Michael J.; Michaelides, Angelos; Alfè, Dario</p> <p>2016-06-01</p> <p>Diffusion Monte Carlo (DMC) simulations for fermions are becoming the standard for providing high-quality reference data in systems that are too large to be investigated via quantum chemical approaches. DMC with the fixed-node approximation relies on modifications of the Green's function to avoid singularities near the nodal surface of the trial wave function. Here we show that these modifications affect the DMC energies in a way that is not size consistent, resulting in large <span class="hlt">time</span>-step errors. Building on the modifications of Umrigar et al. and DePasquale et al. we propose a simple Green's function modification that restores size consistency to large values of the <span class="hlt">time</span> step, which substantially reduces <span class="hlt">time</span>-step errors. This algorithm also yields remarkable speedups of up to two orders of magnitude in the calculation of molecule-molecule binding energies and crystal cohesive energies, thus extending the horizons of what is possible with DMC.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25612627','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25612627"><span id="translatedtitle">Validating the <span class="hlt">Accuracy</span> of Reaction <span class="hlt">Time</span> Assessment on Computer-Based Tablet Devices.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schatz, Philip; Ybarra, Vincent; Leitner, Donald</p> <p>2015-08-01</p> <p>Computer-based assessment has evolved to tablet-based devices. Despite the availability of tablets and "apps," there is limited research validating their use. We documented <span class="hlt">timing</span> delays between stimulus presentation and (simulated) touch response on iOS devices (3rd- and 4th-generation Apple iPads) and Android devices (Kindle Fire, Google Nexus, Samsung Galaxy) at response intervals of 100, 250, 500, and 1,000 milliseconds (ms). Results showed significantly greater <span class="hlt">timing</span> error on Google Nexus and Samsung tablets (81-97 ms), than Kindle Fire and Apple iPads (27-33 ms). Within Apple devices, iOS 7 obtained significantly lower <span class="hlt">timing</span> error than iOS 6. Simple reaction <span class="hlt">time</span> (RT) trials (250 ms) on tablet devices represent 12% to 40% error (30-100 ms), depending on the device, which decreases considerably for choice RT trials (3-5% error at 1,000 ms). Results raise implications for using the same device for serial clinical assessment of RT using tablets, as well as the need for calibration of software and hardware. PMID:25612627</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=monitoring+AND+performance&pg=2&id=EJ864667','ERIC'); return false;" href="http://eric.ed.gov/?q=monitoring+AND+performance&pg=2&id=EJ864667"><span id="translatedtitle">Monitoring Rater Performance over <span class="hlt">Time</span>: A Framework for Detecting Differential <span class="hlt">Accuracy</span> and Differential Scale Category Use</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Myford, Carol M.; Wolfe, Edward W.</p> <p>2009-01-01</p> <p>In this study, we describe a framework for monitoring rater performance over <span class="hlt">time</span>. We present several statistical indices to identify raters whose standards drift and explain how to use those indices operationally. To illustrate the use of the framework, we analyzed rating data from the 2002 Advanced Placement English Literature and Composition…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3818346','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3818346"><span id="translatedtitle">State-Based Metacognition: How <span class="hlt">Time</span> of Day Affects the <span class="hlt">Accuracy</span> of Metamemory</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Hourihan, Kathleen L.; Benjamin, Aaron S.</p> <p>2013-01-01</p> <p>Though there is an abundance of research on how stimulus characteristics and encoding conditions affect metamemory, and how those effects either successfully do or do not mirror effects on memory, there is little research on whether and how characteristics of participants’ states—like mood, fatigue, or hunger—affect metamemory. The present study examined whether metamemory ability fluctuates with <span class="hlt">time</span> of day. Specifically, we evaluated whether learners can successfully account for the effects of <span class="hlt">time</span> of day on their memory, and whether metacognitive monitoring is more accurate at an individual’s optimal <span class="hlt">time</span> of day. Young adults studied and recalled lists of words in both the morning and the afternoon, providing various metamemory judgments during each test session. We replicated the finding that young participants recalled more words in the afternoon than in the morning. Prior to study, participants did not predict superior recall in the afternoon, but they did after they had an opportunity to study the list (but before the test on that material). We also found that item-by-item predictions were more accurate in the afternoon, suggesting that self-regulated learning may benefit from being scheduled during <span class="hlt">times</span> of day that accord with individuals’ peak arousal. PMID:23742008</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25612627','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25612627"><span id="translatedtitle">Validating the <span class="hlt">Accuracy</span> of Reaction <span class="hlt">Time</span> Assessment on Computer-Based Tablet Devices.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schatz, Philip; Ybarra, Vincent; Leitner, Donald</p> <p>2015-08-01</p> <p>Computer-based assessment has evolved to tablet-based devices. Despite the availability of tablets and "apps," there is limited research validating their use. We documented <span class="hlt">timing</span> delays between stimulus presentation and (simulated) touch response on iOS devices (3rd- and 4th-generation Apple iPads) and Android devices (Kindle Fire, Google Nexus, Samsung Galaxy) at response intervals of 100, 250, 500, and 1,000 milliseconds (ms). Results showed significantly greater <span class="hlt">timing</span> error on Google Nexus and Samsung tablets (81-97 ms), than Kindle Fire and Apple iPads (27-33 ms). Within Apple devices, iOS 7 obtained significantly lower <span class="hlt">timing</span> error than iOS 6. Simple reaction <span class="hlt">time</span> (RT) trials (250 ms) on tablet devices represent 12% to 40% error (30-100 ms), depending on the device, which decreases considerably for choice RT trials (3-5% error at 1,000 ms). Results raise implications for using the same device for serial clinical assessment of RT using tablets, as well as the need for calibration of software and hardware.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27029102','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27029102"><span id="translatedtitle">There Is <span class="hlt">Time</span> for Calculation in Speed Chess, and Calculation <span class="hlt">Accuracy</span> Increases With Expertise.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chang, Yu-Hsuan A; Lane, David M</p> <p>2016-01-01</p> <p>The recognition-action theory of chess skill holds that expertise in chess is due primarily to the ability to recognize familiar patterns of pieces. Despite its widespread acclaim, empirical evidence for this theory is indirect. One source of indirect evidence is that there is a high correlation between speed chess and standard chess. Assuming that there is little or no <span class="hlt">time</span> for calculation in speed chess, this high correlation implies that calculation is not the primary factor in standard chess. Two studies were conducted analyzing 100 games of speed chess. In Study 1, we examined the distributions of move <span class="hlt">times</span>, and the key finding was that players often spent considerable <span class="hlt">time</span> on a few moves. Moreover, stronger players were more likely than weaker players to do so. Study 2 examined skill differences in calculation by examining poor moves. The stronger players made proportionally fewer blunders (moves that a 2-ply search would have revealed to be errors). Overall, the poor moves made by the weaker players would have required a less extensive search to be revealed as poor moves than the poor moves made by the stronger players. Apparently, the stronger players are searching deeper and more accurately. These results are difficult to reconcile with the view that speed chess does not allow players <span class="hlt">time</span> to calculate extensively and call into question the assertion that the high correlation between speed chess and standard chess supports recognition-action theory. PMID:27029102</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_10");'>10</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li class="active"><span>12</span></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_12 --> <div id="page_13" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="241"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2003JCoPh.191..206G&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2003JCoPh.191..206G&link_type=ABSTRACT"><span id="translatedtitle">Design and analysis of ALE schemes with provable second-order <span class="hlt">time-accuracy</span> for inviscid and viscous flow simulations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Geuzaine, Philippe; Grandmont, Céline; Farhat, Charbel</p> <p>2003-10-01</p> <p>We consider the solution of inviscid as well as viscous unsteady flow problems with moving boundaries by the arbitrary Lagrangian-Eulerian (ALE) method. We present two computational approaches for achieving formal second-order <span class="hlt">time-accuracy</span> on moving grids. The first approach is based on flux <span class="hlt">time</span>-averaging, and the second one on mesh configuration <span class="hlt">time</span>-averaging. In both cases, we prove that formally second-order <span class="hlt">time</span>-accurate ALE schemes can be designed. We illustrate our theoretical findings and highlight their impact on practice with the solution of inviscid as well as viscous, unsteady, nonlinear flow problems associated with the AGARD Wing 445.6 and a complete F-16 configuration.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFMEP52A..05D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFMEP52A..05D"><span id="translatedtitle">Placing <span class="hlt">Absolute</span> <span class="hlt">Timing</span> on Basin Incision Adjacent to the Colorado Front Range: Results from Meteoric and in Situ 10BE Dating</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Duehnforth, M.; Anderson, R. S.; Ward, D.</p> <p>2010-12-01</p> <p>A sequence of six levels of gravel-capped surfaces, mapped as Pliocene to Holocene in age, are cut into Cretaceous shale in the northwestern part of the Denver Basin immediately adjacent to the Colorado Front Range (CFR). The existing relative age constraints and terrace correlations suggest that the incision of the Denver Basin occurred at a steady and uniform rate of 0.1 mm yr-1 since the Pliocene. As <span class="hlt">absolute</span> ages in this landscape are rare, they have the potential to test the reliability of the existing chronology, and to illuminate the detailed history of incision. We explore the <span class="hlt">timing</span> of basin incision and the variability of geomorphic process rates through <span class="hlt">time</span> by dating the three highest surfaces at the northwestern edge of the Denver Basin using both in situ and meteoric 10Be concentrations. As the tectonic conditions have not changed since the Pliocene, much of the variability of generation and abandonment of alluvial surfaces likely reflects the influence of glacial-interglacial climate variations. We selected Gunbarrel Hill (mapped as pre-Rocky Flats (Pliocene)), Table Mountain (mapped as Rocky Flats (early Pleistocene)), and the Pioneer surface (mapped as Verdos (Pleistocene, ~640 ka)) as sample locations. We took two amalgamated clast samples on the Gunbarrel Hill surface, and dated depth profiles using meteoric and in situ 10Be on the Table Mountain and Pioneer surfaces. In addition, we measured the in situ 10Be concentrations of 6 boulder samples from the Table Mountain surface. We find that all three surfaces are significantly younger than expected and that in situ and meteoric age measurements largely agree with each other. The samples from the pre-Rocky Flats site (Gunbarrel Hill) show ages of 250 and 310 ka, ignoring post-depositional surface erosion. The ages of the Table Mountain and Pioneer sites fall within the 120 to 150 ka window. These <span class="hlt">absolute</span> ages overlap with the <span class="hlt">timing</span> of the penultimate glaciation during marine isotope stage (MIS) 6</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012Metro..49..706S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012Metro..49..706S"><span id="translatedtitle">Frequency-domain analysis of <span class="hlt">absolute</span> gravimeters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Svitlov, S.</p> <p>2012-12-01</p> <p>An <span class="hlt">absolute</span> gravimeter is analysed as a linear <span class="hlt">time</span>-invariant system in the frequency domain. Frequency responses of <span class="hlt">absolute</span> gravimeters are derived analytically based on the propagation of the complex exponential signal through their linear measurement functions. Depending on the model of motion and the number of <span class="hlt">time</span>-distance coordinates, an <span class="hlt">absolute</span> gravimeter is considered as a second-order (three-level scheme) or third-order (multiple-level scheme) low-pass filter. It is shown that the behaviour of an atom <span class="hlt">absolute</span> gravimeter in the frequency domain corresponds to that of the three-level corner-cube <span class="hlt">absolute</span> gravimeter. Theoretical results are applied for evaluation of random and systematic measurement errors and optimization of an experiment. The developed theory agrees with known results of an <span class="hlt">absolute</span> gravimeter analysis in the <span class="hlt">time</span> and frequency domains and can be used for measurement uncertainty analyses, building of vibration-isolation systems and synthesis of digital filtering algorithms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19790013324','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19790013324"><span id="translatedtitle">The AFGL <span class="hlt">absolute</span> gravity program</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hammond, J. A.; Iliff, R. L.</p> <p>1978-01-01</p> <p>A brief discussion of the AFGL's (Air Force Geophysics Laboratory) program in <span class="hlt">absolute</span> gravity is presented. Support of outside work and in-house studies relating to gravity instrumentation are discussed. A description of the current transportable system is included and the latest results are presented. These results show good agreement with measurements at the AFGL site by an Italian system. The <span class="hlt">accuracy</span> obtained by the transportable apparatus is better than 0.1 microns sq sec 10 microgal and agreement with previous measurements is within the combined uncertainties of the measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE.9881E..2FC','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE.9881E..2FC"><span id="translatedtitle">Assessing and ensuring GOES-R magnetometer <span class="hlt">accuracy</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Carter, Delano; Todirita, Monica; Kronenwetter, Jeffrey; Dahya, Melissa; Chu, Donald</p> <p>2016-05-01</p> <p>The GOES-R magnetometer subsystem <span class="hlt">accuracy</span> requirement is 1.7 nanoteslas (nT). During quiet <span class="hlt">times</span> (100 nT), <span class="hlt">accuracy</span> is defined as <span class="hlt">absolute</span> mean plus 3 sigma error per axis. During storms (300 nT), <span class="hlt">accuracy</span> is defined as <span class="hlt">absolute</span> mean plus 2 sigma error per axis. Error comes both from outside the magnetometers, e.g. spacecraft fields and misalignments, as well as inside, e.g. zero offset and scale factor errors. Because zero offset and scale factor drift over <span class="hlt">time</span>, it will be necessary to perform annual calibration maneuvers. To predict performance before launch, we have used Monte Carlo simulations and covariance analysis. With the proposed calibration regimen, both suggest that the magnetometer subsystem will meet its <span class="hlt">accuracy</span> requirements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011PMB....56..557M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011PMB....56..557M"><span id="translatedtitle"><span class="hlt">Accuracy</span> and optimal <span class="hlt">timing</span> of activity measurements in estimating the absorbed dose of radioiodine in the treatment of Graves' disease</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Merrill, S.; Horowitz, J.; Traino, A. C.; Chipkin, S. R.; Hollot, C. V.; Chait, Y.</p> <p>2011-02-01</p> <p>Calculation of the therapeutic activity of radioiodine 131I for individualized dosimetry in the treatment of Graves' disease requires an accurate estimate of the thyroid absorbed radiation dose based on a tracer activity administration of 131I. Common approaches (Marinelli-Quimby formula, MIRD algorithm) use, respectively, the effective half-life of radioiodine in the thyroid and the <span class="hlt">time</span>-integrated activity. Many physicians perform one, two, or at most three tracer dose activity measurements at various <span class="hlt">times</span> and calculate the required therapeutic activity by ad hoc methods. In this paper, we study the <span class="hlt">accuracy</span> of estimates of four 'target variables': <span class="hlt">time</span>-integrated activity coefficient, <span class="hlt">time</span> of maximum activity, maximum activity, and effective half-life in the gland. Clinical data from 41 patients who underwent 131I therapy for Graves' disease at the University Hospital in Pisa, Italy, are used for analysis. The radioiodine kinetics are described using a nonlinear mixed-effects model. The distributions of the target variables in the patient population are characterized. Using minimum root mean squared error as the criterion, optimal 1-, 2-, and 3-point sampling schedules are determined for estimation of the target variables, and probabilistic bounds are given for the errors under the optimal <span class="hlt">times</span>. An algorithm is developed for computing the optimal 1-, 2-, and 3-point sampling schedules for the target variables. This algorithm is implemented in a freely available software tool. Taking into consideration 131I effective half-life in the thyroid and measurement noise, the optimal 1-point <span class="hlt">time</span> for <span class="hlt">time</span>-integrated activity coefficient is a measurement 1 week following the tracer dose. Additional measurements give only a slight improvement in <span class="hlt">accuracy</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3510712','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3510712"><span id="translatedtitle">"Right <span class="hlt">Time</span>, Right Place" Health Communication on Twitter: Value and <span class="hlt">Accuracy</span> of Location Information</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Burton, Scott H; Tanner, Kesler W; West, Joshua H; Barnes, Michael D</p> <p>2012-01-01</p> <p>Background Twitter provides various types of location data, including exact Global Positioning System (GPS) coordinates, which could be used for infoveillance and infodemiology (ie, the study and monitoring of online health information), health communication, and interventions. Despite its potential, Twitter location information is not well understood or well documented, limiting its public health utility. Objective The objective of this study was to document and describe the various types of location information available in Twitter. The different types of location data that can be ascertained from Twitter users are described. This information is key to informing future research on the availability, usability, and limitations of such location data. Methods Location data was gathered directly from Twitter using its application programming interface (API). The maximum tweets allowed by Twitter were gathered (1% of the total tweets) over 2 separate weeks in October and November 2011. The final dataset consisted of 23.8 million tweets from 9.5 million unique users. Frequencies for each of the location options were calculated to determine the prevalence of the various location data options by region of the world, <span class="hlt">time</span> zone, and state within the United States. Data from the US Census Bureau were also compiled to determine population proportions in each state, and Pearson correlation coefficients were used to compare each state’s population with the number of Twitter users who enable the GPS location option. Results The GPS location data could be ascertained for 2.02% of tweets and 2.70% of unique users. Using a simple text-matching approach, 17.13% of user profiles in the 4 continental US <span class="hlt">time</span> zones were able to be used to determine the user’s city and state. Agreement between GPS data and data from the text-matching approach was high (87.69%). Furthermore, there was a significant correlation between the number of Twitter users per state and the 2010 US Census state</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1148992','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1148992"><span id="translatedtitle">A <span class="hlt">Time</span> Projection Chamber for High <span class="hlt">Accuracy</span> and Precision Fission Cross-Section Measurements</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>T. Hill; K. Jewell; M. Heffner; D. Carter; M. Cunningham; V. Riot; J. Ruz; S. Sangiorgio; B. Seilhan; L. Snyder; D. M. Asner; S. Stave; G. Tatishvili; L. Wood; R. G. Baker; J. L. Klay; R. Kudo; S. Barrett; J. King; M. Leonard; W. Loveland; L. Yao; C. Brune; S. Grimes; N. Kornilov; T. N. Massey; J. Bundgaard; D. L. Duke; U. Greife; U. Hager; E. Burgett; J. Deaven; V. Kleinrath; C. McGrath; B. Wendt; N. Hertel; D. Isenhower; N. Pickle; H. Qu; S. Sharma; R. T. Thornton; D. Tovwell; R. S. Towell; S.</p> <p>2014-09-01</p> <p>The fission <span class="hlt">Time</span> Projection Chamber (fissionTPC) is a compact (15 cm diameter) two-chamber MICROMEGAS TPC designed to make precision cross-section measurements of neutron-induced fission. The actinide targets are placed on the central cathode and irradiated with a neutron beam that passes axially through the TPC inducing fission in the target. The 4p acceptance for fission fragments and complete charged particle track reconstruction are powerful features of the fissionTPC which will be used to measure fission cross-sections and examine the associated systematic errors. This paper provides a detailed description of the design requirements, the design solutions, and the initial performance of the fissionTPC.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=serial+AND+production&id=EJ961248','ERIC'); return false;" href="http://eric.ed.gov/?q=serial+AND+production&id=EJ961248"><span id="translatedtitle">Bottom-Up Mechanisms Are Involved in the Relation between <span class="hlt">Accuracy</span> in <span class="hlt">Timing</span> Tasks and Intelligence--Further Evidence Using Manipulations of State Motivation</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ullen, Fredrik; Soderlund, Therese; Kaaria, Lenita; Madison, Guy</p> <p>2012-01-01</p> <p>Intelligence correlates with <span class="hlt">accuracy</span> in various <span class="hlt">timing</span> tasks. Such correlations could be due to both bottom-up mechanisms, e.g. neural properties that influence both temporal <span class="hlt">accuracy</span> and cognitive processing, and differences in top-down control. We have investigated the <span class="hlt">timing</span>-intelligence relation using a simple temporal motor task, isochronous…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4490812','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4490812"><span id="translatedtitle">Estimating the <span class="hlt">absolute</span> wealth of households</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Gerkey, Drew; Hadley, Craig</p> <p>2015-01-01</p> <p>Abstract Objective To estimate the <span class="hlt">absolute</span> wealth of households using data from demographic and health surveys. Methods We developed a new metric, the <span class="hlt">absolute</span> wealth estimate, based on the rank of each surveyed household according to its material assets and the assumed shape of the distribution of wealth among surveyed households. Using data from 156 demographic and health surveys in 66 countries, we calculated <span class="hlt">absolute</span> wealth estimates for households. We validated the method by comparing the proportion of households defined as poor using our estimates with published World Bank poverty headcounts. We also compared the <span class="hlt">accuracy</span> of <span class="hlt">absolute</span> versus relative wealth estimates for the prediction of anthropometric measures. Findings The median <span class="hlt">absolute</span> wealth estimates of 1 403 186 households were 2056 international dollars per capita (interquartile range: 723–6103). The proportion of poor households based on <span class="hlt">absolute</span> wealth estimates were strongly correlated with World Bank estimates of populations living on less than 2.00 United States dollars per capita per day (R2 = 0.84). <span class="hlt">Absolute</span> wealth estimates were better predictors of anthropometric measures than relative wealth indexes. Conclusion <span class="hlt">Absolute</span> wealth estimates provide new opportunities for comparative research to assess the effects of economic resources on health and human capital, as well as the long-term health consequences of economic change and inequality. PMID:26170506</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22220483','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22220483"><span id="translatedtitle">Improving the <span class="hlt">accuracy</span> and efficiency of <span class="hlt">time</span>-resolved electronic spectra calculations: Cellular dephasing representation with a prefactor</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zambrano, Eduardo; Šulc, Miroslav; Vaníček, Jiří</p> <p>2013-08-07</p> <p><span class="hlt">Time</span>-resolved electronic spectra can be obtained as the Fourier transform of a special type of <span class="hlt">time</span> correlation function known as fidelity amplitude, which, in turn, can be evaluated approximately and efficiently with the dephasing representation. Here we improve both the <span class="hlt">accuracy</span> of this approximation—with an amplitude correction derived from the phase-space propagator—and its efficiency—with an improved cellular scheme employing inverse Weierstrass transform and optimal scaling of the cell size. We demonstrate the advantages of the new methodology by computing dispersed <span class="hlt">time</span>-resolved stimulated emission spectra in the harmonic potential, pyrazine, and the NCO molecule. In contrast, we show that in strongly chaotic systems such as the quartic oscillator the original dephasing representation is more appropriate than either the cellular or prefactor-corrected methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009ams..book..145K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009ams..book..145K"><span id="translatedtitle"><span class="hlt">Absolute</span> High-Precision Localisation of an Unmanned Ground Vehicle by Using Real-<span class="hlt">Time</span> Aerial Video Imagery for Geo-referenced Orthophoto Registration</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kuhnert, Lars; Ax, Markus; Langer, Matthias; Nguyen van, Duong; Kuhnert, Klaus-Dieter</p> <p></p> <p>This paper describes an <span class="hlt">absolute</span> localisation method for an unmanned ground vehicle (UGV) if GPS is unavailable for the vehicle. The basic idea is to combine an unmanned aerial vehicle (UAV) to the ground vehicle and use it as an external sensor platform to achieve an <span class="hlt">absolute</span> localisation of the robotic team. Beside the discussion of the rather naive method directly using the GPS position of the aerial robot to deduce the ground robot's position the main focus of this paper lies on the indirect usage of the telemetry data of the aerial robot combined with live video images of an onboard camera to realise a registration of local video images with apriori registered orthophotos. This yields to a precise driftless <span class="hlt">absolute</span> localisation of the unmanned ground vehicle. Experiments with our robotic team (AMOR and PSYCHE) successfully verify this approach.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AGUFM.G51B0368C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AGUFM.G51B0368C"><span id="translatedtitle"><span class="hlt">Absolute</span> Gravity Datum in the Age of Cold Atom Gravimeters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Childers, V. A.; Eckl, M. C.</p> <p>2014-12-01</p> <p>The international gravity datum is defined today by the International Gravity Standardization Net of 1971 (IGSN-71). The data supporting this network was measured in the 1950s and 60s using pendulum and spring-based gravimeter ties (plus some new ballistic <span class="hlt">absolute</span> meters) to replace the prior protocol of referencing all gravity values to the earlier Potsdam value. Since this <span class="hlt">time</span>, gravimeter technology has advanced significantly with the development and refinement of the FG-5 (the current standard of the industry) and again with the soon-to-be-available cold atom interferometric <span class="hlt">absolute</span> gravimeters. This latest development is anticipated to provide improvement in the range of two orders of magnitude as compared to the measurement <span class="hlt">accuracy</span> of technology utilized to develop ISGN-71. In this presentation, we will explore how the IGSN-71 might best be "modernized" given today's requirements and available instruments and resources. The National Geodetic Survey (NGS), along with other relevant US Government agencies, is concerned about establishing gravity control to establish and maintain high order geodetic networks as part of the nation's essential infrastructure. The need to modernize the nation's geodetic infrastructure was highlighted in "Precise Geodetic Infrastructure, National Requirements for a Shared Resource" National Academy of Science, 2010. The NGS mission, as dictated by Congress, is to establish and maintain the National Spatial Reference System, which includes gravity measurements. <span class="hlt">Absolute</span> gravimeters measure the total gravity field directly and do not involve ties to other measurements. Periodic "intercomparisons" of multiple <span class="hlt">absolute</span> gravimeters at reference gravity sites are used to constrain the behavior of the instruments to ensure that each would yield reasonably similar measurements of the same location (i.e. yield a sufficiently consistent datum when measured in disparate locales). New atomic interferometric gravimeters promise a significant</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4610435','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4610435"><span id="translatedtitle">A Long Distance Phase-Sensitive Optical <span class="hlt">Time</span> Domain Reflectometer with Simple Structure and High Locating <span class="hlt">Accuracy</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Shi, Yi; Feng, Hao; Zeng, Zhoumo</p> <p>2015-01-01</p> <p>A phase-sensitive optical <span class="hlt">time</span> domain reflectometer (Φ-OTDR) can be used for pipeline security. However, the sensing distance (less than 20 km) of traditional Φ-OTDR is too short for the needs of typical oil and gas pipeline monitoring applications (30–50 km). A simple structure Φ-OTDR system utilizing long pulse, balanced amplified detector and heterodyne detection is proposed in this paper and the sensing range is thereby increased to 60 km. Through analyzing the sensing principle of Φ-OTDR, a novel locating strategy is proposed to maintain the locating <span class="hlt">accuracy</span> at a few meters when a long pulse (5 µs) is used. The increased pulse width deteriorates the <span class="hlt">time</span> series of each sensing point seriously. In order to eliminate the deterioration, a data processing technique combining wavelet and empirical mode decomposition is applied in this system. The experiment results show that the sensing distance can be increased to 60 km and the locating <span class="hlt">accuracy</span> is maintained at 6.8 m. PMID:26340628</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26340628','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26340628"><span id="translatedtitle">A Long Distance Phase-Sensitive Optical <span class="hlt">Time</span> Domain Reflectometer with Simple Structure and High Locating <span class="hlt">Accuracy</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Shi, Yi; Feng, Hao; Zeng, Zhoumo</p> <p>2015-09-02</p> <p>A phase-sensitive optical <span class="hlt">time</span> domain reflectometer (Φ-OTDR) can be used for pipeline security. However, the sensing distance (less than 20 km) of traditional Φ-OTDR is too short for the needs of typical oil and gas pipeline monitoring applications (30-50 km). A simple structure Φ-OTDR system utilizing long pulse, balanced amplified detector and heterodyne detection is proposed in this paper and the sensing range is thereby increased to 60 km. Through analyzing the sensing principle of Φ-OTDR, a novel locating strategy is proposed to maintain the locating <span class="hlt">accuracy</span> at a few meters when a long pulse (5 µs) is used. The increased pulse width deteriorates the <span class="hlt">time</span> series of each sensing point seriously. In order to eliminate the deterioration, a data processing technique combining wavelet and empirical mode decomposition is applied in this system. The experiment results show that the sensing distance can be increased to 60 km and the locating <span class="hlt">accuracy</span> is maintained at 6.8 m.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25761394','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25761394"><span id="translatedtitle">A reminder on millisecond <span class="hlt">timing</span> <span class="hlt">accuracy</span> and potential replication failure in computer-based psychology experiments: An open letter.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Plant, Richard R</p> <p>2016-03-01</p> <p>There is an ongoing 'replication crisis' across the field of psychology in which researchers, funders, and members of the public are questioning the results of some scientific studies and the validity of the data they are based upon. However, few have considered that a growing proportion of research in modern psychology is conducted using a computer. Could it simply be that the hardware and software, or experiment generator, being used to run the experiment itself be a cause of millisecond <span class="hlt">timing</span> error and subsequent replication failure? This article serves as a reminder that millisecond <span class="hlt">timing</span> <span class="hlt">accuracy</span> in psychology studies remains an important issue and that care needs to be taken to ensure that studies can be replicated on current computer hardware and software. PMID:25761394</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AdSpR..58.1390T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AdSpR..58.1390T"><span id="translatedtitle">Improvement of orbit determination <span class="hlt">accuracy</span> for Beidou Navigation Satellite System with Two-way Satellite <span class="hlt">Time</span> Frequency Transfer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tang, Chengpan; Hu, Xiaogong; Zhou, Shanshi; Guo, Rui; He, Feng; Liu, Li; Zhu, Lingfeng; Li, Xiaojie; Wu, Shan; Zhao, Gang; Yu, Yang; Cao, Yueling</p> <p>2016-10-01</p> <p>The Beidou Navigation Satellite System (BDS) manages to estimate simultaneously the orbits and clock offsets of navigation satellites, using code and carrier phase measurements of a regional network within China. The satellite clock offsets are also directly measured with Two-way Satellite <span class="hlt">Time</span> Frequency Transfer (TWSTFT). Satellite laser ranging (SLR) residuals and comparisons with the precise ephemeris indicate that the radial error of GEO satellites is much larger than that of IGSO and MEO satellites and that the BDS orbit <span class="hlt">accuracy</span> is worse than GPS. In order to improve the orbit determination <span class="hlt">accuracy</span> for BDS, a new orbit determination strategy is proposed, in which the satellite clock measurements from TWSTFT are fixed as known values, and only the orbits of the satellites are solved. However, a constant systematic error at the nanosecond level can be found in the clock measurements, which is obtained and then corrected by differencing the clock measurements and the clock estimates from orbit determination. The effectiveness of the new strategy is verified by a GPS regional network orbit determination experiment. With the IGS final clock products fixed, the orbit determination and prediction <span class="hlt">accuracy</span> for GPS satellites improve by more than 50% and the 12-h prediction User Range Error (URE) is better than 0.12 m. By processing a 25-day of measurement from the BDS regional network, an optimal strategy for the satellite-clock-fixed orbit determination is identified. User Equivalent Ranging Error is reduced by 27.6% for GEO satellites, but no apparent reduction is found for IGSO/MEO satellites. The SLR residuals exhibit reductions by 59% and 32% for IGSO satellites but no reductions for GEO and MEO satellites.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EGUGA..17.7826G','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EGUGA..17.7826G"><span id="translatedtitle">Estimating subsurface water volumes and transit <span class="hlt">times</span> in Hokkaido river catchments, Japan, using high-<span class="hlt">accuracy</span> tritium analysis</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Gusyev, Maksym; Yamazaki, Yusuke; Morgenstern, Uwe; Stewart, Mike; Kashiwaya, Kazuhisa; Hirai, Yasuyuki; Kuribayashi, Daisuke; Sawano, Hisaya</p> <p>2015-04-01</p> <p>The goal of this study is to estimate subsurface water transit <span class="hlt">times</span> and volumes in headwater catchments of Hokkaido, Japan, using the New Zealand high-<span class="hlt">accuracy</span> tritium analysis technique. Transit <span class="hlt">time</span> provides insights into the subsurface water storage and therefore provides a robust and quick approach to quantifying the subsurface groundwater volume. Our method is based on tritium measurements in river water. Tritium is a component of meteoric water, decays with a half-life of 12.32 years, and is inert in the subsurface after the water enters the groundwater system. Therefore, tritium is ideally suited for characterization of the catchment's responses and can provide information on mean water transit <span class="hlt">times</span> up to 200 years. Only in recent years has it become possible to use tritium for dating of stream and river water, due to the fading impact of the bomb-tritium from thermo-nuclear weapons testing, and due to improved measurement <span class="hlt">accuracy</span> for the extremely low natural tritium concentrations. Transit <span class="hlt">time</span> of the water discharge is one of the most crucial parameters for understanding the response of catchments and estimating subsurface water volume. While many tritium transit <span class="hlt">time</span> studies have been conducted in New Zealand, only a limited number of tritium studies have been conducted in Japan. In addition, the meteorological, orographic and geological conditions of Hokkaido Island are similar to those in parts of New Zealand, allowing for comparison between these regions. In 2014, three field trips were conducted in Hokkaido in June, July and October to sample river water at river gauging stations operated by the Ministry of Land, Infrastructure, Transport and Tourism (MLIT). These stations have altitudes between 36 m and 860 m MSL and drainage areas between 45 and 377 km2. Each sampled point is located upstream of MLIT dams, with hourly measurements of precipitation and river water levels enabling us to distinguish between the snow melt and baseflow contributions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/23586876','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/23586876"><span id="translatedtitle"><span class="hlt">Absolute</span> biological needs.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>McLeod, Stephen</p> <p>2014-07-01</p> <p><span class="hlt">Absolute</span> needs (as against instrumental needs) are independent of the ends, goals and purposes of personal agents. Against the view that the only needs are instrumental needs, David Wiggins and Garrett Thomson have defended <span class="hlt">absolute</span> needs on the grounds that the verb 'need' has instrumental and <span class="hlt">absolute</span> senses. While remaining neutral about it, this article does not adopt that approach. Instead, it suggests that there are <span class="hlt">absolute</span> biological needs. The <span class="hlt">absolute</span> nature of these needs is defended by appeal to: their objectivity (as against mind-dependence); the universality of the phenomenon of needing across the plant and animal kingdoms; the impossibility that biological needs depend wholly upon the exercise of the abilities characteristic of personal agency; the contention that the possession of biological needs is prior to the possession of the abilities characteristic of personal agency. Finally, three philosophical usages of 'normative' are distinguished. On two of these, to describe a phenomenon or claim as 'normative' is to describe it as value-dependent. A description of a phenomenon or claim as 'normative' in the third sense does not entail such value-dependency, though it leaves open the possibility that value depends upon the phenomenon or upon the truth of the claim. It is argued that while survival needs (or claims about them) may well be normative in this third sense, they are normative in neither of the first two. Thus, the idea of <span class="hlt">absolute</span> need is not inherently normative in either of the first two senses. PMID:23586876</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23586876','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23586876"><span id="translatedtitle"><span class="hlt">Absolute</span> biological needs.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>McLeod, Stephen</p> <p>2014-07-01</p> <p><span class="hlt">Absolute</span> needs (as against instrumental needs) are independent of the ends, goals and purposes of personal agents. Against the view that the only needs are instrumental needs, David Wiggins and Garrett Thomson have defended <span class="hlt">absolute</span> needs on the grounds that the verb 'need' has instrumental and <span class="hlt">absolute</span> senses. While remaining neutral about it, this article does not adopt that approach. Instead, it suggests that there are <span class="hlt">absolute</span> biological needs. The <span class="hlt">absolute</span> nature of these needs is defended by appeal to: their objectivity (as against mind-dependence); the universality of the phenomenon of needing across the plant and animal kingdoms; the impossibility that biological needs depend wholly upon the exercise of the abilities characteristic of personal agency; the contention that the possession of biological needs is prior to the possession of the abilities characteristic of personal agency. Finally, three philosophical usages of 'normative' are distinguished. On two of these, to describe a phenomenon or claim as 'normative' is to describe it as value-dependent. A description of a phenomenon or claim as 'normative' in the third sense does not entail such value-dependency, though it leaves open the possibility that value depends upon the phenomenon or upon the truth of the claim. It is argued that while survival needs (or claims about them) may well be normative in this third sense, they are normative in neither of the first two. Thus, the idea of <span class="hlt">absolute</span> need is not inherently normative in either of the first two senses.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_11");'>11</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li class="active"><span>13</span></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_13 --> <div id="page_14" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="261"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4944798','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4944798"><span id="translatedtitle"><span class="hlt">Accuracy</span> of Perceived Estimated Travel <span class="hlt">Time</span> by EMS to a Trauma Center in San Bernardino County, California</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Neeki, Michael M.; MacNeil, Colin; Toy, Jake; Dong, Fanglong; Vara, Richard; Powell, Joe; Pennington, Troy; Kwong, Eugene</p> <p>2016-01-01</p> <p>Introduction Mobilization of trauma resources has the potential to cause ripple effects throughout hospital operations. One major factor affecting efficient utilization of trauma resources is a discrepancy between the prehospital estimated <span class="hlt">time</span> of arrival (ETA) as communicated by emergency medical services (EMS) personnel and their actual <span class="hlt">time</span> of arrival (TOA). The current study aimed to assess the <span class="hlt">accuracy</span> of the perceived prehospital estimated arrival <span class="hlt">time</span> by EMS personnel in comparison to their actual arrival <span class="hlt">time</span> at a Level II trauma center in San Bernardino County, California. Methods This retrospective study included traumas classified as alerts or activations that were transported to Arrowhead Regional Medical Center in 2013. We obtained estimated arrival <span class="hlt">time</span> and actual arrival <span class="hlt">time</span> for each transport from the Surgery Department Trauma Registry. The difference between the median of ETA and actual TOA by EMS crews to the trauma center was calculated for these transports. Additional variables assessed included <span class="hlt">time</span> of day and month during which the transport took place. Results A total of 2,454 patients classified as traumas were identified in the Surgery Department Trauma Registry. After exclusion of trauma consults, walk-ins, handoffs between agencies, downgraded traumas, traumas missing information, and traumas transported by agencies other than American Medical Response, Ontario Fire, Rialto Fire or San Bernardino County Fire, we included a final sample size of 555 alert and activation classified traumas in the final analysis. When combining all transports by the included EMS agencies, the median of the ETA was 10 minutes and the median of the actual TOA was 22 minutes (median of difference=9 minutes, p<0.0001). Furthermore, when comparing the difference between trauma alerts and activations, trauma activations demonstrated an equal or larger difference in the median of the estimated and actual <span class="hlt">time</span> of arrival (p<0.0001). We also found month and <span class="hlt">time</span> of</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2009PhDT.......273S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2009PhDT.......273S"><span id="translatedtitle"><span class="hlt">Accuracy</span> of sign interpreting and real-<span class="hlt">time</span> captioning of science videos for the delivery of instruction to deaf students</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sadler, Karen L.</p> <p>2009-04-01</p> <p>The purpose of this study was to quantitatively examine the impact of third-party support service providers on the quality of science information available to deaf students in regular science classrooms. Three different videotapes that were developed by NASA for high school science classrooms were selected for the study, allowing for different concepts and vocabulary to be examined. The focus was on the <span class="hlt">accuracy</span> of translation as measured by the number of key science words included in the transcripts (captions) or videos (interpreted). Data were collected via transcripts completed by CART (computer assisted real-<span class="hlt">time</span> captionists) or through videos of sign language interpreters. All participants were required to listen to and translate these NASA educational videos with no prior experience with this information so as not to influence their delivery. CART personnel using captions were found to be significantly more accurate in the delivery of science words as compared to the sign language interpreters in this study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23527146','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23527146"><span id="translatedtitle">Eye exercises enhance <span class="hlt">accuracy</span> and letter recognition, but not reaction <span class="hlt">time</span>, in a modified rapid serial visual presentation task.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Di Noto, Paula; Uta, Sorin; DeSouza, Joseph F X</p> <p>2013-01-01</p> <p>Eye exercises have been prescribed to resolve a multitude of eye-related problems. However, studies on the efficacy of eye exercises are lacking, mainly due to the absence of simple assessment tools in the clinic. Because similar regions of the brain are responsible for eye movements and visual attention, we used a modified rapid serial visual presentation (RSVP) to assess any measurable effect of short-term eye exercise in improvements within these domains. In the present study, twenty subjects were equally divided into control and experimental groups, each of which performed a pre-training RSVP assessment where target letters, to which subjects were asked to respond to by pressing a spacebar, were serially and rapidly presented. Response <span class="hlt">time</span> to target letters, <span class="hlt">accuracy</span> of correctly responding to target letters, and correct identification of target letters in each of 12 sessions was measured. The experimental group then performed active eye exercises, while the control group performed a task that minimized eye movements for 18.5 minutes. A final post-training RSVP assessment was performed by both groups and response <span class="hlt">time</span>, <span class="hlt">accuracy</span>, and letter identification were compared between and within subject groups both pre- and post-training. Subjects who performed eye exercises were more accurate in responding to target letters separated by one distractor and in letter identification in the post-training RSVP assessment, while latency of responses were unchanged between and within groups. This suggests that eye exercises may prove useful in enhancing cognitive performance on tasks related to attention and memory over a very brief course of training, and RSVP may be a useful measure of this efficacy. Further research is needed on eye exercises to determine whether they are an effective treatment for patients with cognitive and eye-related disorders.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4678543','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4678543"><span id="translatedtitle">Effect of storage <span class="hlt">time</span> and framework design on the <span class="hlt">accuracy</span> of maxillary cobalt-chromium cast removable partial dentures</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Viswambaran, M.; Sundaram, R. K.</p> <p>2015-01-01</p> <p>Statement of Problem: Inaccuracies in the fit of palatal major connectors may be related to distortion of the wax pattern due to prolonged storage <span class="hlt">time</span> and faulty major connector design. Purpose: This in vitro study was carried out to find out the effect of storage <span class="hlt">time</span> and major connector design on the <span class="hlt">accuracy</span> of cobalt-chromium cast removable partial dentures (RPDs). Materials and Methods: A brass metal die with a Kennedy Class III, modification 1, the partially edentulous arch was used as a master die. Thirty-six refractory casts were fabricated from the master die. The refractory casts were divided into three groups (Group I: Anterior-posterior palatal bar, Group II: Palatal strap and Group III: Palatal plate) based on the design of maxillary major connector and subdivided into four groups (sub Group A: 01 h, sub Group B: 03 h, Sub Group C: 06 h, and sub Group D: 24 h) based on the storage <span class="hlt">time</span>. For each group, 12 frameworks were fabricated. The influence of wax pattern storage <span class="hlt">time</span> and the <span class="hlt">accuracy</span> of the fit palatal major connector designs on the master die were compared. Casting defects (nodules/incompleteness) of the frameworks were also evaluated before finishing and polishing. Repeated measures analysis of variance was used to analyze the data. Results: The gap discrepancy was least in sub Group A (01 h) followed by sub Group B (03 h) and C (06 h) and most in sub Group D (24 h). Statistically significant differences (P < 0.05 in all locations L1–L5) in the fit of the framework were related to the design of the major connector. The gap discrepancy was least in Group I (anterior-posterior palatal bar) followed by Group II (palatal strap) and most in Group II (palatal plate). Conclusions: It is recommended that the wax patterns for RPD to be invested immediately on completion of the wax procedure. The selection of a major connector design is crucial for an accurate fit of RPD. PMID:26681850</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5049779','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5049779"><span id="translatedtitle"><span class="hlt">Accuracy</span> of a Real-<span class="hlt">Time</span>, Computerized, Binocular, Three-Dimensional Trajectory-Tracking Device for Recording Functional Mandibular Movements</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhao, Tian; Yang, Huifang; Sui, Huaxin; Salvi, Satyajeet Sudhir; Wang, Yong; Sun, Yuchun</p> <p>2016-01-01</p> <p>Objective Developments in digital technology have permitted researchers to study mandibular movements. Here, the <span class="hlt">accuracy</span> of a real-<span class="hlt">time</span>, computerized, binocular, three-dimensional (3D) trajectory-tracking device for recording functional mandibular movements was evaluated. Methods An occlusal splint without the occlusal region was created based on a plaster cast of the lower dentition. The splint was rigidly connected with a target on its labial side and seated on the cast. The cast was then rigidly attached to the stage of a high-precision triaxial electronic translator, which was used to move the target-cast-stage complex. Half-circular movements (5.00-mm radius) in three planes (XOY, XOZ, YOZ) and linear movements along the x-axis were performed at 5.00 mm/s. All trajectory points were recorded with the binocular 3D trajectory-tracking device and fitted to arcs or lines, respectively, with the Imageware software. To analyze the <span class="hlt">accuracy</span> of the trajectory-tracking device, the mean distances between the trajectory points and the fitted arcs or lines were measured, and the mean differences between the lengths of the fitted arcs’ radii and a set value (5.00 mm) were then calculated. A one-way analysis of variance was used to evaluate the spatial consistency of the recording <span class="hlt">accuracy</span> in three different planes. Results The mean distances between the trajectory points and fitted arcs or lines were 0.076 ± 0.033 mm or 0.089 ± 0.014 mm. The mean difference between the lengths of the fitted arcs’ radii and the set value (5.00 mm) was 0.025 ± 0.071 mm. A one-way ANOVA showed that the recording errors in three different planes were not statistically significant. Conclusion These results suggest that the device can record certain movements at 5.00 mm/s, which is similar to the speed of functional mandibular movements. In addition, the recordings had an error of <0.1 mm and good spatial consistency. Thus, the device meets some of the requirements necessary for</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70117138','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70117138"><span id="translatedtitle"><span class="hlt">Accuracy</span> of travel <span class="hlt">time</span> distribution (TTD) models as affected by TTD complexity, observation errors, and model and tracer selection</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Green, Christopher T.; Zhang, Yong; Jurgens, Bryant C.; Starn, J. Jeffrey; Landon, Matthew K.</p> <p>2014-01-01</p> <p>Analytical models of the travel <span class="hlt">time</span> distribution (TTD) from a source area to a sample location are often used to estimate groundwater ages and solute concentration trends. The <span class="hlt">accuracies</span> of these models are not well known for geologically complex aquifers. In this study, synthetic datasets were used to quantify the <span class="hlt">accuracy</span> of four analytical TTD models as affected by TTD complexity, observation errors, model selection, and tracer selection. Synthetic TTDs and tracer data were generated from existing numerical models with complex hydrofacies distributions for one public-supply well and 14 monitoring wells in the Central Valley, California. Analytical TTD models were calibrated to synthetic tracer data, and prediction errors were determined for estimates of TTDs and conservative tracer (NO3−) concentrations. Analytical models included a new, scale-dependent dispersivity model (SDM) for two-dimensional transport from the watertable to a well, and three other established analytical models. The relative influence of the error sources (TTD complexity, observation error, model selection, and tracer selection) depended on the type of prediction. Geological complexity gave rise to complex TTDs in monitoring wells that strongly affected errors of the estimated TTDs. However, prediction errors for NO3− and median age depended more on tracer concentration errors. The SDM tended to give the most accurate estimates of the vertical velocity and other predictions, although TTD model selection had minor effects overall. Adding tracers improved predictions if the new tracers had different input histories. Studies using TTD models should focus on the factors that most strongly affect the desired predictions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27513452','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27513452"><span id="translatedtitle">The effect of pain on task switching: pain reduces <span class="hlt">accuracy</span> and increases reaction <span class="hlt">times</span> across multiple switching paradigms.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Attridge, Nina; Keogh, Edmund; Eccleston, Christopher</p> <p>2016-10-01</p> <p>Pain disrupts attention, which may have negative consequences for daily life for people with acute or chronic pain. It has been suggested that switching between tasks may leave us particularly susceptible to pain-related attentional disruption, because we need to disengage our attention from one task before shifting it onto another. Switching tasks typically elicit lower <span class="hlt">accuracies</span> and/or longer reaction <span class="hlt">times</span> when participants switch to a new task compared with repeating the same task, and pain may exacerbate this effect. We present 3 studies to test this hypothesis. In study 1, participants completed 2 versions of an alternating runs switching task under pain-free and thermal pain-induction conditions. Pain did not affect performance on either task. In studies 2 and 3, we examined 7 versions of the switching task using large general population samples, experiencing a variety of naturally occurring pain conditions, recruited and tested on the internet. On all tasks, participants with pain had longer reaction <span class="hlt">times</span> on both switch and repeat trials compared with participants without pain, but pain did not increase switch costs. In studies 2 and 3, we also investigated the effects of type of pain, duration of pain, and analgesics on task performance. We conclude that pain has a small dampening effect on performance overall on switching tasks. This suggests that pain interrupts attention even when participants are engaged in a trial, not only when attention has been disengaged for shifting to a new task set.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1231575-absolute-path-command','SCIGOV-ESTSC'); return false;" href="http://www.osti.gov/scitech/biblio/1231575-absolute-path-command"><span id="translatedtitle">The <span class="hlt">absolute</span> path command</span></a></p> <p><a target="_blank" href=""></a></p> <p></p> <p>2012-05-11</p> <p>The ap command traveres all symlinks in a given file, directory, or executable name to identify the final <span class="hlt">absolute</span> path. It can print just the final path, each intermediate link along with the symlink chan, and the permissions and ownership of each directory component in the final path. It has functionality similar to "which", except that it shows the final path instead of the first path. It is also similar to "pwd", but it canmore » provide the <span class="hlt">absolute</span> path to a relative directory from the current working directory.« less</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/1231575','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/1231575"><span id="translatedtitle">The <span class="hlt">absolute</span> path command</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Moody, A.</p> <p>2012-05-11</p> <p>The ap command traveres all symlinks in a given file, directory, or executable name to identify the final <span class="hlt">absolute</span> path. It can print just the final path, each intermediate link along with the symlink chan, and the permissions and ownership of each directory component in the final path. It has functionality similar to "which", except that it shows the final path instead of the first path. It is also similar to "pwd", but it can provide the <span class="hlt">absolute</span> path to a relative directory from the current working directory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4281187','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4281187"><span id="translatedtitle">Effect of Storage <span class="hlt">Time</span> of Extended-Pour and Conventional Alginate Impressions on Dimensional <span class="hlt">Accuracy</span> of Casts</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Rohanian, Ahmad; Ommati Shabestari, Ghasem; Zeighami, Somayeh; Samadi, Mohammad Javad; Shamshiri, Ahmad Reza</p> <p>2014-01-01</p> <p>Objectives: Some manufacturers claim to have produced new irreversible hydro-colloids that are able to maintain their dimensional stability during storage. The present study evaluated the effect of storage <span class="hlt">time</span> on dimensional stability of three alginates: Hydrogum 5, Tropicalgin and Alginoplast. Materials and Methods: In this experimental in-vitro trial, a total of 90 alginate impressions were made from a Dentoform model using Hydrogum 5, Tropicalgin and Alginoplast alginates. The impressions were stored in a sealed plastic bag without a damp paper towel for 0, 24, 48, 72 and 120 hours and then poured with type III dental stone. Cross-arch (facial of 6 to facial of 6 on the opposite side) and antero-posterior (distal of right first molar to the ipsilateral central incisor) measurements were made with a digital caliper on the casts. Data were analyzed by two-way and one-way ANOVA and Tukey’s post-hoc test (P<0.05). Results: Alginate type and the pouring <span class="hlt">time</span> significantly affected the dimensional stability of alginate impressions (both Ps<0.001). Pouring of Hydrogum 5 impressions can be delayed for up to 120 hours without significant dimensional changes. Alginoplast impressions may be poured after 72 hours, but Tropicalgin should be poured immediately and the storage <span class="hlt">time</span> should not be more than 24 hours. Conclusion: Immediate pouring of alginate impressions provides the highest <span class="hlt">accuracy</span> in reproducing the teeth and adjacent tissues; however, this study demonstrated that pouring may be delayed for up to five days using extended-pour (Hydrogum 5) alginates. PMID:25628695</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016AIPC.1706t0003E','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016AIPC.1706t0003E"><span id="translatedtitle">Structural health monitoring ultrasonic thickness measurement <span class="hlt">accuracy</span> and reliability of various <span class="hlt">time</span>-of-flight calculation methods</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Eason, Thomas J.; Bond, Leonard J.; Lozev, Mark G.</p> <p>2016-02-01</p> <p>The <span class="hlt">accuracy</span>, precision, and reliability of ultrasonic thickness structural health monitoring systems are discussed in-cluding the influence of systematic and environmental factors. To quantify some of these factors, a compression wave ultrasonic thickness structural health monitoring experiment is conducted on a flat calibration block at ambient temperature with forty four thin-film sol-gel transducers and various <span class="hlt">time</span>-of-flight thickness calculation methods. As an initial calibration, the voltage response signals from each sensor are used to determine the common material velocity as well as the signal offset unique to each calculation method. Next, the measurement precision of the thickness error of each method is determined with a proposed weighted censored relative maximum likelihood analysis technique incorporating the propagation of asymmetric measurement uncertainty. The results are presented as upper and lower confidence limits analogous to the a90/95 terminology used in industry recognized Probability-of-Detection assessments. Future work is proposed to apply the statistical analysis technique to quantify measurement precision of various thickness calculation methods under different environmental conditions such as high temperature, rough back-wall surface, and system degradation with an intended application to monitor naphthenic acid corrosion in oil refineries.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26677827','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26677827"><span id="translatedtitle"><span class="hlt">Accuracy</span> of PARTwear Inertial Sensor and Optojump Optical Measurement System for Measuring Ground Contact <span class="hlt">Time</span> During Running.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ammann, Rahel; Taube, Wolfgang; Wyss, Thomas</p> <p>2016-07-01</p> <p>Ammann, R, Taube, W, and Wyss, T. <span class="hlt">Accuracy</span> of PARTwear inertial sensor and Optojump optical measurement system for measuring ground contact <span class="hlt">time</span> during running. J Strength Cond Res 30(7): 2057-2063, 2016-The aim of this study was to validate the detection of ground contact <span class="hlt">time</span> (GCT) during running in 2 differently working systems: a small inertial measurement sensor, PARTwear (PW), worn on the shoe laces, and the optical measurement system, Optojump (OJ), placed on the track. Twelve well-trained subjects performed 12 runs each on an indoor track at speeds ranging from 3.0 to 9.0 m·s. GCT of one step per run (total 144) was simultaneously obtained by the PW, the OJ, and a high-speed video camera (HSC), whereby the latter served as reference system. The sampling rate was 1,000 Hz for all methods. Compared with the HSC, the PW and the OJ systems underestimated GCT by -1.3 ± 6.1% and -16.5 ± 6.7% (p-values ≤ 0.05), respectively. The intraclass correlation coefficients between PW and HSC and between OJ and HSC were 0.984 and 0.853 (p-values < 0.001), respectively. Despite the constant systematic underestimation of GCT, analyses indicated that PW successfully recorded GCT over a wide range of speeds. However, results showed only moderate validity for the OJ system, with increasing errors when speed decreased. In conclusion, the PW proved to be a highly useful and valid application, and its use can be recommended not only for laboratory settings but also for field applications. In contrast, data on GCT obtained by OJ during running must be treated with caution, specifically when running speed changes or when comparisons are made with GCT data collected by other measurement systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24322224','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24322224"><span id="translatedtitle"><span class="hlt">Absolute</span> photoacoustic thermometry in deep tissue.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Yao, Junjie; Ke, Haixin; Tai, Stephen; Zhou, Yong; Wang, Lihong V</p> <p>2013-12-15</p> <p>Photoacoustic thermography is a promising tool for temperature measurement in deep tissue. Here we propose an <span class="hlt">absolute</span> temperature measurement method based on the dual temperature dependences of the Grüneisen parameter and the speed of sound in tissue. By taking ratiometric measurements at two adjacent temperatures, we can eliminate the factors that are temperature irrelevant but difficult to correct for in deep tissue. To validate our method, <span class="hlt">absolute</span> temperatures of blood-filled tubes embedded ~9 mm deep in chicken tissue were measured in a biologically relevant range from 28°C to 46°C. The temperature measurement <span class="hlt">accuracy</span> was ~0.6°C. The results suggest that our method can be potentially used for <span class="hlt">absolute</span> temperature monitoring in deep tissue during thermotherapy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25321248','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25321248"><span id="translatedtitle">Effect of <span class="hlt">time</span> discretization of the imaging process on the <span class="hlt">accuracy</span> of trajectory estimation in fluorescence microscopy.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wong, Yau; Chao, Jerry; Lin, Zhiping; Ober, Raimund J</p> <p>2014-08-25</p> <p>In fluorescence microscopy, high-speed imaging is often necessary for the proper visualization and analysis of fast subcellular dynamics. Here, we examine how the speed of image acquisition affects the <span class="hlt">accuracy</span> with which parameters such as the starting position and speed of a microscopic non-stationary fluorescent object can be estimated from the resulting image sequence. Specifically, we use a Fisher information-based performance bound to investigate the detector-dependent effect of frame rate on the <span class="hlt">accuracy</span> of parameter estimation. We demonstrate that when a charge-coupled device detector is used, the estimation <span class="hlt">accuracy</span> deteriorates as the frame rate increases beyond a point where the detector's readout noise begins to overwhelm the low number of photons detected in each frame. In contrast, we show that when an electron-multiplying charge-coupled device (EMCCD) detector is used, the estimation <span class="hlt">accuracy</span> improves with increasing frame rate. In fact, at high frame rates where the low number of photons detected in each frame renders the fluorescent object difficult to detect visually, imaging with an EMCCD detector represents a natural implementation of the Ultrahigh <span class="hlt">Accuracy</span> Imaging Modality, and enables estimation with an <span class="hlt">accuracy</span> approaching that which is attainable only when a hypothetical noiseless detector is used. PMID:25321248</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014GeoJI.197.1250T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014GeoJI.197.1250T"><span id="translatedtitle">An efficient finite-difference method with high-order <span class="hlt">accuracy</span> in both <span class="hlt">time</span> and space domains for modelling scalar-wave propagation</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tan, Sirui; Huang, Lianjie</p> <p>2014-05-01</p> <p>For modelling large-scale 3-D scalar-wave propagation, the finite-difference (FD) method with high-order <span class="hlt">accuracy</span> in space but second-order <span class="hlt">accuracy</span> in <span class="hlt">time</span> is widely used because of its relatively low requirements of computer memory. We develop a novel staggered-grid (SG) FD method with high-order <span class="hlt">accuracy</span> not only in space, but also in <span class="hlt">time</span>, for solving 2- and 3-D scalar-wave equations. We determine the coefficients of the FD operator in the joint <span class="hlt">time</span>-space domain to achieve high-order <span class="hlt">accuracy</span> in <span class="hlt">time</span> while preserving high-order <span class="hlt">accuracy</span> in space. Our new FD scheme is based on a stencil that contains a few more grid points than the standard stencil. It is 2M-th-order accurate in space and fourth-order accurate in <span class="hlt">time</span> when using 2M grid points along each axis and wavefields at one <span class="hlt">time</span> step as the standard SGFD method. We validate the <span class="hlt">accuracy</span> and efficiency of our new FD scheme using dispersion analysis and numerical modelling of scalar-wave propagation in 2- and 3-D complex models with a wide range of velocity contrasts. For media with a velocity contrast up to five, our new FD scheme is approximately two <span class="hlt">times</span> more computationally efficient than the standard SGFD scheme with almost the same computer-memory requirement as the latter. Further numerical experiments demonstrate that our new FD scheme loses its advantages over the standard SGFD scheme if the velocity contrast is 10. However, for most large-scale geophysical applications, the velocity contrasts often range approximately from 1 to 3. Our new method is thus particularly useful for large-scale 3-D scalar-wave modelling and full-waveform inversion.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27301704','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27301704"><span id="translatedtitle"><span class="hlt">Time</span>-resolved <span class="hlt">absolute</span> measurements by electro-optic effect of giant electromagnetic pulses due to laser-plasma interaction in nanosecond regime.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Consoli, F; De Angelis, R; Duvillaret, L; Andreoli, P L; Cipriani, M; Cristofari, G; Di Giorgio, G; Ingenito, F; Verona, C</p> <p>2016-01-01</p> <p>We describe the first electro-optical <span class="hlt">absolute</span> measurements of electromagnetic pulses (EMPs) generated by laser-plasma interaction in nanosecond regime. Laser intensities are inertial-confinement-fusion (ICF) relevant and wavelength is 1054 nm. These are the first direct EMP amplitude measurements with the detector rather close and in direct view of the plasma. A maximum field of 261 kV/m was measured, two orders of magnitude higher than previous measurements by conductive probes on nanosecond regime lasers with much higher energy. The analysis of measurements and of particle-in-cell simulations indicates that signals match the emission of charged particles detected in the same experiment, and suggests that anisotropic particle emission from target, X-ray photoionization and charge implantation on surfaces directly exposed to plasma, could be important EMP contributions. Significant information achieved on EMP features and sources is crucial for future plants of laser-plasma acceleration and inertial-confinement-fusion and for the use as effective plasma diagnostics. It also opens to remarkable applications of laser-plasma interaction as intense source of RF-microwaves for studies on materials and devices, EMP-radiation-hardening and electromagnetic compatibility. The demonstrated extreme effectivity of electric-fields detection in laser-plasma context by electro-optic effect, leads to great potential for characterization of laser-plasma interaction and generated Terahertz radiation. PMID:27301704</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4908660','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4908660"><span id="translatedtitle"><span class="hlt">Time</span>-resolved <span class="hlt">absolute</span> measurements by electro-optic effect of giant electromagnetic pulses due to laser-plasma interaction in nanosecond regime</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Consoli, F.; De Angelis, R.; Duvillaret, L.; Andreoli, P. L.; Cipriani, M.; Cristofari, G.; Di Giorgio, G.; Ingenito, F.; Verona, C.</p> <p>2016-01-01</p> <p>We describe the first electro-optical <span class="hlt">absolute</span> measurements of electromagnetic pulses (EMPs) generated by laser-plasma interaction in nanosecond regime. Laser intensities are inertial-confinement-fusion (ICF) relevant and wavelength is 1054 nm. These are the first direct EMP amplitude measurements with the detector rather close and in direct view of the plasma. A maximum field of 261 kV/m was measured, two orders of magnitude higher than previous measurements by conductive probes on nanosecond regime lasers with much higher energy. The analysis of measurements and of particle-in-cell simulations indicates that signals match the emission of charged particles detected in the same experiment, and suggests that anisotropic particle emission from target, X-ray photoionization and charge implantation on surfaces directly exposed to plasma, could be important EMP contributions. Significant information achieved on EMP features and sources is crucial for future plants of laser-plasma acceleration and inertial-confinement-fusion and for the use as effective plasma diagnostics. It also opens to remarkable applications of laser-plasma interaction as intense source of RF-microwaves for studies on materials and devices, EMP-radiation-hardening and electromagnetic compatibility. The demonstrated extreme effectivity of electric-fields detection in laser-plasma context by electro-optic effect, leads to great potential for characterization of laser-plasma interaction and generated Terahertz radiation. PMID:27301704</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NatSR...627889C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NatSR...627889C"><span id="translatedtitle"><span class="hlt">Time</span>-resolved <span class="hlt">absolute</span> measurements by electro-optic effect of giant electromagnetic pulses due to laser-plasma interaction in nanosecond regime</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Consoli, F.; de Angelis, R.; Duvillaret, L.; Andreoli, P. L.; Cipriani, M.; Cristofari, G.; di Giorgio, G.; Ingenito, F.; Verona, C.</p> <p>2016-06-01</p> <p>We describe the first electro-optical <span class="hlt">absolute</span> measurements of electromagnetic pulses (EMPs) generated by laser-plasma interaction in nanosecond regime. Laser intensities are inertial-confinement-fusion (ICF) relevant and wavelength is 1054 nm. These are the first direct EMP amplitude measurements with the detector rather close and in direct view of the plasma. A maximum field of 261 kV/m was measured, two orders of magnitude higher than previous measurements by conductive probes on nanosecond regime lasers with much higher energy. The analysis of measurements and of particle-in-cell simulations indicates that signals match the emission of charged particles detected in the same experiment, and suggests that anisotropic particle emission from target, X-ray photoionization and charge implantation on surfaces directly exposed to plasma, could be important EMP contributions. Significant information achieved on EMP features and sources is crucial for future plants of laser-plasma acceleration and inertial-confinement-fusion and for the use as effective plasma diagnostics. It also opens to remarkable applications of laser-plasma interaction as intense source of RF-microwaves for studies on materials and devices, EMP-radiation-hardening and electromagnetic compatibility. The demonstrated extreme effectivity of electric-fields detection in laser-plasma context by electro-optic effect, leads to great potential for characterization of laser-plasma interaction and generated Terahertz radiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27301704','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27301704"><span id="translatedtitle"><span class="hlt">Time</span>-resolved <span class="hlt">absolute</span> measurements by electro-optic effect of giant electromagnetic pulses due to laser-plasma interaction in nanosecond regime.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Consoli, F; De Angelis, R; Duvillaret, L; Andreoli, P L; Cipriani, M; Cristofari, G; Di Giorgio, G; Ingenito, F; Verona, C</p> <p>2016-06-15</p> <p>We describe the first electro-optical <span class="hlt">absolute</span> measurements of electromagnetic pulses (EMPs) generated by laser-plasma interaction in nanosecond regime. Laser intensities are inertial-confinement-fusion (ICF) relevant and wavelength is 1054 nm. These are the first direct EMP amplitude measurements with the detector rather close and in direct view of the plasma. A maximum field of 261 kV/m was measured, two orders of magnitude higher than previous measurements by conductive probes on nanosecond regime lasers with much higher energy. The analysis of measurements and of particle-in-cell simulations indicates that signals match the emission of charged particles detected in the same experiment, and suggests that anisotropic particle emission from target, X-ray photoionization and charge implantation on surfaces directly exposed to plasma, could be important EMP contributions. Significant information achieved on EMP features and sources is crucial for future plants of laser-plasma acceleration and inertial-confinement-fusion and for the use as effective plasma diagnostics. It also opens to remarkable applications of laser-plasma interaction as intense source of RF-microwaves for studies on materials and devices, EMP-radiation-hardening and electromagnetic compatibility. The demonstrated extreme effectivity of electric-fields detection in laser-plasma context by electro-optic effect, leads to great potential for characterization of laser-plasma interaction and generated Terahertz radiation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20000064542&hterms=alexander+bruce&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dalexander%2Bbruce','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20000064542&hterms=alexander+bruce&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D10%26Ntt%3Dalexander%2Bbruce"><span id="translatedtitle">Issues in <span class="hlt">Absolute</span> Spectral Radiometric Calibration: Intercomparison of Eight Sources</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Goetz, Alexander F. H.; Kindel, Bruce; Pilewskie, Peter</p> <p>1998-01-01</p> <p>The application of atmospheric models to AVIRIS and other spectral imaging data to derive surface reflectance requires that the sensor output be calibrated to <span class="hlt">absolute</span> radiance. Uncertainties in <span class="hlt">absolute</span> calibration are to be expected, and claims of 92% <span class="hlt">accuracy</span> have been published. Measurements of accurate surface albedos and cloud absorption to be used in radiative balance calculations depend critically on knowing the <span class="hlt">absolute</span> spectral-radiometric response of the sensor. The Earth Observing System project is implementing a rigorous program of <span class="hlt">absolute</span> radiometric calibration for all optical sensors. Since a number of imaging instruments that provide output in terms of <span class="hlt">absolute</span> radiance are calibrated at different sites, it is important to determine the errors that can be expected among calibration sites. Another question exists about the errors in the <span class="hlt">absolute</span> knowledge of the exoatmospheric spectral solar irradiance.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_12");'>12</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li class="active"><span>14</span></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_14 --> <div id="page_15" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="281"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9677E..2FL','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9677E..2FL"><span id="translatedtitle">The correction of vibration in frequency scanning interferometry based <span class="hlt">absolute</span> distance measurement system for dynamic measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lu, Cheng; Liu, Guodong; Liu, Bingguo; Chen, Fengdong; Zhuang, Zhitao; Xu, Xinke; Gan, Yu</p> <p>2015-10-01</p> <p><span class="hlt">Absolute</span> distance measurement systems are of significant interest in the field of metrology, which could improve the manufacturing efficiency and <span class="hlt">accuracy</span> of large assemblies in fields such as aircraft construction, automotive engineering, and the production of modern windmill blades. Frequency scanning interferometry demonstrates noticeable advantages as an <span class="hlt">absolute</span> distance measurement system which has a high precision and doesn't depend on a cooperative target. In this paper , the influence of inevitable vibration in the frequency scanning interferometry based <span class="hlt">absolute</span> distance measurement system is analyzed. The distance spectrum is broadened as the existence of Doppler effect caused by vibration, which will bring in a measurement error more than 103 <span class="hlt">times</span> bigger than the changes of optical path difference. In order to decrease the influence of vibration, the changes of the optical path difference are monitored by a frequency stabilized laser, which runs parallel to the frequency scanning interferometry. The experiment has verified the effectiveness of this method.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24634064','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24634064"><span id="translatedtitle">Brief report: <span class="hlt">accuracy</span> and response <span class="hlt">time</span> for the recognition of facial emotions in a large sample of children with autism spectrum disorders.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Fink, Elian; de Rosnay, Marc; Wierda, Marlies; Koot, Hans M; Begeer, Sander</p> <p>2014-09-01</p> <p>The empirical literature has presented inconsistent evidence for deficits in the recognition of basic emotion expressions in children with autism spectrum disorders (ASD), which may be due to the focus on research with relatively small sample sizes. Additionally, it is proposed that although children with ASD may correctly identify emotion expression they rely on more deliberate, more <span class="hlt">time</span>-consuming strategies in order to accurately recognize emotion expressions when compared to typically developing children. In the current study, we examine both emotion recognition <span class="hlt">accuracy</span> and response <span class="hlt">time</span> in a large sample of children, and explore the moderating influence of verbal ability on these findings. The sample consisted of 86 children with ASD (M age = 10.65) and 114 typically developing children (M age = 10.32) between 7 and 13 years of age. All children completed a pre-test (emotion word-word matching), and test phase consisting of basic emotion recognition, whereby they were required to match a target emotion expression to the correct emotion word; <span class="hlt">accuracy</span> and response <span class="hlt">time</span> were recorded. Verbal IQ was controlled for in the analyses. We found no evidence of a systematic deficit in emotion recognition <span class="hlt">accuracy</span> or response <span class="hlt">time</span> for children with ASD, controlling for verbal ability. However, when controlling for children's <span class="hlt">accuracy</span> in word-word matching, children with ASD had significantly lower emotion recognition <span class="hlt">accuracy</span> when compared to typically developing children. The findings suggest that the social impairments observed in children with ASD are not the result of marked deficits in basic emotion recognition <span class="hlt">accuracy</span> or longer response <span class="hlt">times</span>. However, children with ASD may be relying on other perceptual skills (such as advanced word-word matching) to complete emotion recognition tasks at a similar level as typically developing children.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=memory+AND+fMRI&pg=4&id=EJ1000145','ERIC'); return false;" href="http://eric.ed.gov/?q=memory+AND+fMRI&pg=4&id=EJ1000145"><span id="translatedtitle">The Episodic Engram Transformed: <span class="hlt">Time</span> Reduces Retrieval-Related Brain Activity but Correlates It with Memory <span class="hlt">Accuracy</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Furman, Orit; Mendelsohn, Avi; Dudai, Yadin</p> <p>2012-01-01</p> <p>We took snapshots of human brain activity with fMRI during retrieval of realistic episodic memory over several months. Three groups of participants were scanned during a memory test either hours, weeks, or months after viewing a documentary movie. High recognition <span class="hlt">accuracy</span> after hours decreased after weeks and remained at similar levels after…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGC32C..03C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGC32C..03C"><span id="translatedtitle">Prospects for the Moon as an SI-Traceable <span class="hlt">Absolute</span> Spectroradiometric Standard for Satellite Remote Sensing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Cramer, C. E.; Stone, T. C.; Lykke, K.; Woodward, J. T.</p> <p>2015-12-01</p> <p>The Earth's Moon has many physical properties that make it suitable for use as a reference light source for radiometric calibration of remote sensing satellite instruments. Lunar calibration has been successfully applied to many imagers in orbit, including both MODIS instruments and NPP-VIIRS, using the USGS ROLO model to predict the reference exoatmospheric lunar irradiance. Sensor response trending was developed for SeaWIFS with a relative <span class="hlt">accuracy</span> better than 0.1 % per year with lunar calibration techniques. However, the Moon rarely is used as an <span class="hlt">absolute</span> reference for on-orbit calibration, primarily due to uncertainties in the ROLO model <span class="hlt">absolute</span> scale of 5%-10%. But this limitation lies only with the models - the Moon itself is radiometrically stable, and development of a high-<span class="hlt">accuracy</span> <span class="hlt">absolute</span> lunar reference is inherently feasible. A program has been undertaken by NIST to collect <span class="hlt">absolute</span> measurements of the lunar spectral irradiance with <span class="hlt">absolute</span> <span class="hlt">accuracy</span> <1 % (k=2), traceable to SI radiometric units. Initial Moon observations were acquired from the Whipple Observatory on Mt. Hopkins, Arizona, elevation 2367 meters, with continuous spectral coverage from 380 nm to 1040 nm at ~3 nm resolution. The lunar spectrometer acquired calibration measurements several <span class="hlt">times</span> each observing night by pointing to a calibrated integrating sphere source. The lunar spectral irradiance at the top of the atmosphere was derived from a <span class="hlt">time</span> series of ground-based measurements by a Langley analysis that incorporated measured atmospheric conditions and ROLO model predictions for the change in irradiance resulting from the changing Sun-Moon-Observer geometry throughout each night. Two nights were selected for further study. An extensive error analysis, which includes instrument calibration and atmospheric correction terms, shows a combined standard uncertainty under 1 % over most of the spectral range. Comparison of these two nights' spectral irradiance measurements with predictions</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015EPSC...10..717D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015EPSC...10..717D"><span id="translatedtitle"><span class="hlt">Absolute</span> magnitudes of trans-neptunian objects</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Duffard, R.; Alvarez-candal, A.; Pinilla-Alonso, N.; Ortiz, J. L.; Morales, N.; Santos-Sanz, P.; Thirouin, A.</p> <p>2015-10-01</p> <p>Accurate measurements of diameters of trans- Neptunian objects are extremely complicated to obtain. Radiomatric techniques applied to thermal measurements can provide good results, but precise <span class="hlt">absolute</span> magnitudes are needed to constrain diameters and albedos. Our objective is to measure accurate <span class="hlt">absolute</span> magnitudes for a sample of trans- Neptunian objects, many of which have been observed, and modelled, by the "TNOs are cool" team, one of Herschel Space Observatory key projects grantes with ~ 400 hours of observing <span class="hlt">time</span>. We observed 56 objects in filters V and R, if possible. These data, along with data available in the literature, was used to obtain phase curves and to measure <span class="hlt">absolute</span> magnitudes by assuming a linear trend of the phase curves and considering magnitude variability due to rotational light-curve. In total we obtained 234 new magnitudes for the 56 objects, 6 of them with no reported previous measurements. Including the data from the literature we report a total of 109 <span class="hlt">absolute</span> magnitudes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20160006426','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20160006426"><span id="translatedtitle">Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory (CLARREO)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Leckey, John P.</p> <p>2015-01-01</p> <p>The Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory (CLARREO) is a mission, led and developed by NASA, that will measure a variety of climate variables with an unprecedented <span class="hlt">accuracy</span> to quantify and attribute climate change. CLARREO consists of three separate instruments: an infrared (IR) spectrometer, a reflected solar (RS) spectrometer, and a radio occultation (RO) instrument. The mission will contain orbiting radiometers with sufficient <span class="hlt">accuracy</span>, including on orbit verification, to calibrate other space-based instrumentation, increasing their respective <span class="hlt">accuracy</span> by as much as an order of magnitude. The IR spectrometer is a Fourier Transform spectrometer (FTS) working in the 5 to 50 microns wavelength region with a goal of 0.1 K (k = 3) <span class="hlt">accuracy</span>. The FTS will achieve this <span class="hlt">accuracy</span> using phase change cells to verify thermistor <span class="hlt">accuracy</span> and heated halos to verify blackbody emissivity, both on orbit. The RS spectrometer will measure the reflectance of the atmosphere in the 0.32 to 2.3 microns wavelength region with an <span class="hlt">accuracy</span> of 0.3% (k = 2). The status of the instrumentation packages and potential mission options will be presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20040110742','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20040110742"><span id="translatedtitle"><span class="hlt">Absolute</span> Equilibrium Entropy</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shebalin, John V.</p> <p>1997-01-01</p> <p>The entropy associated with <span class="hlt">absolute</span> equilibrium ensemble theories of ideal, homogeneous, fluid and magneto-fluid turbulence is discussed and the three-dimensional fluid case is examined in detail. A sigma-function is defined, whose minimum value with respect to global parameters is the entropy. A comparison is made between the use of global functions sigma and phase functions H (associated with the development of various H-theorems of ideal turbulence). It is shown that the two approaches are complimentary though conceptually different: H-theorems show that an isolated system tends to equilibrium while sigma-functions allow the demonstration that entropy never decreases when two previously isolated systems are combined. This provides a more complete picture of entropy in the statistical mechanics of ideal fluids.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24227878','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24227878"><span id="translatedtitle">Prospective evaluation of the VITEK MS for the routine identification of bacteria and yeast in the clinical microbiology laboratory: assessment of <span class="hlt">accuracy</span> of identification and turnaround <span class="hlt">time</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Charnot-Katsikas, Angella; Tesic, Vera; Boonlayangoor, Sue; Bethel, Cindy; Frank, Karen M</p> <p>2014-02-01</p> <p>This study assessed the <span class="hlt">accuracy</span> of bacterial and yeast identification using the VITEK MS, and the <span class="hlt">time</span> to reporting of isolates before and after its implementation in routine clinical practice. Three hundred and sixty-two isolates of bacteria and yeast, consisting of a variety of clinical isolates and American Type Culture Collection strains, were tested. Results were compared with reference identifications from the VITEK 2 system and with 16S rRNA sequence analysis. The VITEK MS provided an acceptable identification to species level for 283 (78 %) isolates. Considering organisms for which genus-level identification is acceptable for routine clinical care, 315 isolates (87 %) had an acceptable identification. Six isolates (2 %) were identified incorrectly, five of which were Shigella species. Finally, the <span class="hlt">time</span> for reporting the identifications was decreased significantly after implementation of the VITEK MS for a total mean reduction in <span class="hlt">time</span> of 10.52 h (P<0.0001). Overall, <span class="hlt">accuracy</span> of the VITEK MS was comparable or superior to that from the VITEK 2. The findings were also comparable to other studies examining the <span class="hlt">accuracy</span> of the VITEK MS, although differences exist, depending on the diversity of species represented as well as on the versions of the databases used. The VITEK MS can be incorporated effectively into routine use in a clinical microbiology laboratory and future expansion of the database should provide improved <span class="hlt">accuracy</span> for the identification of micro-organisms.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22340056','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22340056"><span id="translatedtitle"><span class="hlt">Absolute</span> properties of the triple star HP Aurigae</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Lacy, Claud H. Sandberg; Burks, Charles L.; Torres, Guillermo; Wolf, Marek E-mail: clburks@email.uark.edu E-mail: wolf@cesnet.cz</p> <p>2014-01-01</p> <p>New photometric, spectroscopic, and eclipse <span class="hlt">timing</span> observations of the eclipsing binary star HP Aur allow for very accurate orbital determinations, even in the presence of a third body and transient starspot activity. The eclipsing binary masses are determined to an <span class="hlt">accuracy</span> of ±0.4% and the radii to ±0.6%. The masses are 0.9543 ± 0.0041 and 0.8094 ± 0.0036 solar masses, and the radii are 1.0278 ± 0.0042 and 0.7758 ± 0.0034 solar radii, respectively. The orbital period in the outer orbit is accurately determined for the first <span class="hlt">time</span>: 4.332 ± 0.011 yr. A comparison with current theories of stellar evolution shows that the components' <span class="hlt">absolute</span> properties can be well-matched by the current models at an age of about 7 billion years.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4270426','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4270426"><span id="translatedtitle">An Extra Dimension to Decision-Making in Animals: The Three-way Trade-off between Speed, Effort per-Unit-<span class="hlt">Time</span> and <span class="hlt">Accuracy</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>de Froment, Adrian J.; Rubenstein, Daniel I.; Levin, Simon A.</p> <p>2014-01-01</p> <p>The standard view in biology is that all animals, from bumblebees to human beings, face a trade-off between speed and <span class="hlt">accuracy</span> as they search for resources and mates, and attempt to avoid predators. For example, the more <span class="hlt">time</span> a forager spends out of cover gathering information about potential food sources the more likely it is to make accurate decisions about which sources are most rewarding. However, when the cost of <span class="hlt">time</span> spent out of cover rises (e.g. in the presence of a predator) the optimal strategy is for the forager to spend less <span class="hlt">time</span> gathering information and to accept a corresponding decline in the <span class="hlt">accuracy</span> of its decisions. We suggest that this familiar picture is missing a crucial dimension: the amount of effort an animal expends on gathering information in each unit of <span class="hlt">time</span>. This is important because an animal that can respond to changing <span class="hlt">time</span> costs by modulating its level of effort per-unit-<span class="hlt">time</span> does not have to accept the same decrease in <span class="hlt">accuracy</span> that an animal limited to a simple speed-<span class="hlt">accuracy</span> trade-off must bear in the same situation. Instead, it can direct additional effort towards (i) reducing the frequency of perceptual errors in the samples it gathers or (ii) increasing the number of samples it gathers per-unit-<span class="hlt">time</span>. Both of these have the effect of allowing it to gather more accurate information within a given period of <span class="hlt">time</span>. We use a modified version of a canonical model of decision-making (the sequential probability ratio test) to show that this ability to substitute effort for <span class="hlt">time</span> confers a fitness advantage in the face of changing <span class="hlt">time</span> costs. We predict that the ability to modulate effort levels will therefore be widespread in nature, and we lay out testable predictions that could be used to detect adaptive modulation of effort levels in laboratory and field studies. Our understanding of decision-making in all species, including our own, will be improved by this more ecologically-complete picture of the three-way tradeoff between <span class="hlt">time</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25522281','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25522281"><span id="translatedtitle">An extra dimension to decision-making in animals: the three-way trade-off between speed, effort per-unit-<span class="hlt">time</span> and <span class="hlt">accuracy</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>de Froment, Adrian J; Rubenstein, Daniel I; Levin, Simon A</p> <p>2014-12-01</p> <p>The standard view in biology is that all animals, from bumblebees to human beings, face a trade-off between speed and <span class="hlt">accuracy</span> as they search for resources and mates, and attempt to avoid predators. For example, the more <span class="hlt">time</span> a forager spends out of cover gathering information about potential food sources the more likely it is to make accurate decisions about which sources are most rewarding. However, when the cost of <span class="hlt">time</span> spent out of cover rises (e.g. in the presence of a predator) the optimal strategy is for the forager to spend less <span class="hlt">time</span> gathering information and to accept a corresponding decline in the <span class="hlt">accuracy</span> of its decisions. We suggest that this familiar picture is missing a crucial dimension: the amount of effort an animal expends on gathering information in each unit of <span class="hlt">time</span>. This is important because an animal that can respond to changing <span class="hlt">time</span> costs by modulating its level of effort per-unit-<span class="hlt">time</span> does not have to accept the same decrease in <span class="hlt">accuracy</span> that an animal limited to a simple speed-<span class="hlt">accuracy</span> trade-off must bear in the same situation. Instead, it can direct additional effort towards (i) reducing the frequency of perceptual errors in the samples it gathers or (ii) increasing the number of samples it gathers per-unit-<span class="hlt">time</span>. Both of these have the effect of allowing it to gather more accurate information within a given period of <span class="hlt">time</span>. We use a modified version of a canonical model of decision-making (the sequential probability ratio test) to show that this ability to substitute effort for <span class="hlt">time</span> confers a fitness advantage in the face of changing <span class="hlt">time</span> costs. We predict that the ability to modulate effort levels will therefore be widespread in nature, and we lay out testable predictions that could be used to detect adaptive modulation of effort levels in laboratory and field studies. Our understanding of decision-making in all species, including our own, will be improved by this more ecologically-complete picture of the three-way tradeoff between <span class="hlt">time</span></p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/2823338','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/2823338"><span id="translatedtitle">[Real-<span class="hlt">time</span> sonography of cholangiolithiasis. Dependence of the diagnostic <span class="hlt">accuracy</span> on the competence of the operator].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Schafroth, E; Saltzman, J; Probst, P</p> <p>1987-09-01</p> <p>The reliability of sonography for demonstrating bile duct stones depends on technical factors and on the experience of the operator. The pick up rate of an experienced operator has been compared with that of three other doctors who had performed sonography only briefly and intermittently. This was based on the results of surgery in 142 patients. The sensitivity of the experienced operator was 72.4% and almost twice that of the other doctors, who showed an <span class="hlt">accuracy</span> of 37.5 and 44%. The competence of the operator depends not only on adequate training, but also on continuous practice.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22218280','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22218280"><span id="translatedtitle"><span class="hlt">Absolute</span> and relative dosimetry for ELIMED</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Cirrone, G. A. P.; Schillaci, F.; Scuderi, V.; Cuttone, G.; Candiano, G.; Musumarra, A.; Pisciotta, P.; Romano, F.; Carpinelli, M.; Presti, D. Lo; Raffaele, L.; Tramontana, A.; Cirio, R.; Sacchi, R.; Monaco, V.; Marchetto, F.; Giordanengo, S.</p> <p>2013-07-26</p> <p>The definition of detectors, methods and procedures for the <span class="hlt">absolute</span> and relative dosimetry of laser-driven proton beams is a crucial step toward the clinical use of this new kind of beams. Hence, one of the ELIMED task, will be the definition of procedures aiming to obtain an <span class="hlt">absolute</span> dose measure at the end of the transport beamline with an <span class="hlt">accuracy</span> as close as possible to the one required for clinical applications (i.e. of the order of 5% or less). Relative dosimetry procedures must be established, as well: they are necessary in order to determine and verify the beam dose distributions and to monitor the beam fluence and the energetic spectra during irradiations. Radiochromic films, CR39, Faraday Cup, Secondary Emission Monitor (SEM) and transmission ionization chamber will be considered, designed and studied in order to perform a fully dosimetric characterization of the ELIMED proton beam.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19890000284&hterms=Hilbert&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DHilbert','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19890000284&hterms=Hilbert&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DHilbert"><span id="translatedtitle"><span class="hlt">Absolute</span> Stability And Hyperstability In Hilbert Space</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Wen, John Ting-Yung</p> <p>1989-01-01</p> <p>Theorems on stabilities of feedback control systems proved. Paper presents recent developments regarding theorems of <span class="hlt">absolute</span> stability and hyperstability of feedforward-and-feedback control system. Theorems applied in analysis of nonlinear, adaptive, and robust control. Extended to provide sufficient conditions for stability in system including nonlinear feedback subsystem and linear <span class="hlt">time</span>-invariant (LTI) feedforward subsystem, state space of which is Hilbert space, and input and output spaces having finite numbers of dimensions. (In case of <span class="hlt">absolute</span> stability, feedback subsystem memoryless and possibly <span class="hlt">time</span> varying. For hyperstability, feedback system dynamical system.)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70015817','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70015817"><span id="translatedtitle">What do we mean by <span class="hlt">accuracy</span> in geomagnetic measurements?</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Green, A.W.</p> <p>1990-01-01</p> <p>High <span class="hlt">accuracy</span> is what distinguishes measurements made at the world's magnetic observatories from other types of geomagnetic measurements. High <span class="hlt">accuracy</span> in determining the <span class="hlt">absolute</span> values of the components of the Earth's magnetic field is essential to studying geomagnetic secular variation and processes at the core mantle boundary, as well as some magnetospheric processes. In some applications of geomagnetic data, precision (or resolution) of measurements may also be important. In addition to <span class="hlt">accuracy</span> and resolution in the amplitude domain, it is necessary to consider these same quantities in the frequency and space domains. New developments in geomagnetic instruments and communications make real-<span class="hlt">time</span>, high <span class="hlt">accuracy</span>, global geomagnetic observatory data sets a real possibility. There is a growing realization in the scientific community of the unique relevance of geomagnetic observatory data to the principal contemporary problems in solid Earth and space physics. Together, these factors provide the promise of a 'renaissance' of the world's geomagnetic observatory system. ?? 1990.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70024269','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70024269"><span id="translatedtitle"><span class="hlt">Absolute</span> <span class="hlt">timing</span> of sulfide and gold mineralization: A comparison of Re-Os molybdenite and Ar-Ar mica methods from the Tintina Gold Belt, Alaska</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Selby, D.; Creaser, R.A.; Hart, C.J.R.; Rombach, C.S.; Thompson, J.F.H.; Smith, M.T.; Bakke, A.A.; Goldfarb, R.J.</p> <p>2002-01-01</p> <p>New Re-Os molybdenite dates from two lode gold deposits of the Tintina Gold Belt, Alaska, provide direct <span class="hlt">timing</span> constraints for sulfide and gold mineralization. At Fort Knox, the Re-Os molybdenite date is identical to the U-Pb zircon age for the host intrusion, supporting an intrusive-related origin for the deposit. However, 40Ar/39Ar dates from hydrothermal and igneous mica are considerably younger. At the Pogo deposit, Re-Os molybdenite dates are also much older than 40Ar/39Ar dates from hydrothermal mica, but dissimilar to the age of local granites. These age relationships indicate that the Re-Os molybdenite method records the <span class="hlt">timing</span> of sulfide and gold mineralization, whereas much younger 40Ar/39Ar dates are affected by post-ore thermal events, slow cooling, and/or systemic analytical effects. The results of this study complement a growing body of evidence to indicate that the Re-Os chronometer in molybdenite can be an accurate and robust tool for establishing <span class="hlt">timing</span> relations in ore systems.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014cos..rept....9M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014cos..rept....9M"><span id="translatedtitle">Updated <span class="hlt">Absolute</span> Flux Calibration of the COS FUV Modes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Massa, D.; Ely, J.; Osten, R.; Penton, S.; Aloisi, A.; Bostroem, A.; Roman-Duval, J.; Proffitt, C.</p> <p>2014-03-01</p> <p>We present newly derived point source <span class="hlt">absolute</span> flux calibrations for the COS FUV modes at both the original and second lifetime positions. The analysis includes observa- tions through the Primary Science Aperture (PSA) of the standard stars WD0308-565, GD71, WD1057+729 and WD0947+857 obtained as part of two calibration programs. Data were were obtained for all of the gratings at all of the original CENWAVE settings at both the original and second lifetime positions and for the G130M CENWAVE = 1222 at the second lifetime position. Data were also obtained with the FUVB segment for the G130M CENWAVE = 1055 and 1096 setting at the second lifetime position. We also present the derivation of L-flats that were used in processing the data and show that the internal consistency of the primary standards is 1%. The <span class="hlt">accuracy</span> of the <span class="hlt">absolute</span> flux calibrations over the UV are estimated to be 1-2% for the medium resolution gratings, and 2-3% over most of the wavelength range of the G140L grating, although the uncertainty can be as large as 5% or more at some G140L wavelengths. We note that these errors are all relative to the optical flux near the V band and small additional errors may be present due to inaccuracies in the V band calibration. In addition, these error estimates are for the <span class="hlt">time</span> at which the flux calibration data were obtained; the <span class="hlt">accuracy</span> of the flux calibration at other <span class="hlt">times</span> can be affected by errors in the <span class="hlt">time</span> dependent sensitivity (TDS) correction.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22149739','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22149739"><span id="translatedtitle"><span class="hlt">Accuracy</span> of Real-<span class="hlt">time</span> Couch Tracking During 3-dimensional Conformal Radiation Therapy, Intensity Modulated Radiation Therapy, and Volumetric Modulated Arc Therapy for Prostate Cancer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wilbert, Juergen; Baier, Kurt; Hermann, Christian; Flentje, Michael; Guckenberger, Matthias</p> <p>2013-01-01</p> <p>Purpose: To evaluate the <span class="hlt">accuracy</span> of real-<span class="hlt">time</span> couch tracking for prostate cancer. Methods and Materials: Intrafractional motion trajectories of 15 prostate cancer patients were the basis for this phantom study; prostate motion had been monitored with the Calypso System. An industrial robot moved a phantom along these trajectories, motion was detected via an infrared camera system, and the robotic HexaPOD couch was used for real-<span class="hlt">time</span> counter-steering. Residual phantom motion during real-<span class="hlt">time</span> tracking was measured with the infrared camera system. Film dosimetry was performed during delivery of 3-dimensional conformal radiation therapy (3D-CRT), step-and-shoot intensity modulated radiation therapy (IMRT), and volumetric modulated arc therapy (VMAT). Results: Motion of the prostate was largest in the anterior-posterior direction, with systematic ( N-Ary-Summation ) and random ({sigma}) errors of 2.3 mm and 2.9 mm, respectively; the prostate was outside a threshold of 5 mm (3D vector) for 25.0%{+-}19.8% of treatment <span class="hlt">time</span>. Real-<span class="hlt">time</span> tracking reduced prostate motion to N-Ary-Summation =0.01 mm and {sigma} = 0.55 mm in the anterior-posterior direction; the prostate remained within a 1-mm and 5-mm threshold for 93.9%{+-}4.6% and 99.7%{+-}0.4% of the <span class="hlt">time</span>, respectively. Without real-<span class="hlt">time</span> tracking, pass rates based on a {gamma} index of 2%/2 mm in film dosimetry ranged between 66% and 72% for 3D-CRT, IMRT, and VMAT, on average. Real-<span class="hlt">time</span> tracking increased pass rates to minimum 98% on average for 3D-CRT, IMRT, and VMAT. Conclusions: Real-<span class="hlt">time</span> couch tracking resulted in submillimeter <span class="hlt">accuracy</span> for prostate cancer, which transferred into high dosimetric <span class="hlt">accuracy</span> independently of whether 3D-CRT, IMRT, or VMAT was used.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3787418','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3787418"><span id="translatedtitle">An All Fiber White Light Interferometric <span class="hlt">Absolute</span> Temperature Measurement System</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Kim, Jeonggon Harrison</p> <p>2008-01-01</p> <p>Recently the author of this article proposed a new signal processing algorithm for an all fiber white light interferometer. In this article, an all fiber white light interferometric <span class="hlt">absolute</span> temperature measurement system is presented using the previously proposed signal processing algorithm. Stability and <span class="hlt">absolute</span> temperature measurement were demonstrated. These two tests demonstrated the feasibility of <span class="hlt">absolute</span> temperature measurement with an <span class="hlt">accuracy</span> of 0.015 fringe and 0.0005 fringe, respectively. A hysteresis test from 373K to 873K was also presented. Finally, robustness of the sensor system towards laser diode temperature drift, AFMZI temperature drift and PZT non-linearity was demonstrated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/20798358','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/20798358"><span id="translatedtitle">Measurement of Disintegration Rates and <span class="hlt">Absolute</span> {gamma}-ray Intensities</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>DeVries, Daniel J.; Griffin, Henry C.</p> <p>2006-03-13</p> <p>The majority of practical radioactive materials decay by modes that include {gamma}-ray emission. For questions of 'how much' or 'how pure', one must know the <span class="hlt">absolute</span> intensities of the major radiations. We are using liquid scintillation counting (LSC) to measurements of disintegration rates, coupled with {gamma}-ray spectroscopy to measure <span class="hlt">absolute</span> {gamma}-ray emission probabilities. Described is a study of the 227Th chain yielding <span class="hlt">absolute</span> {gamma}-ray intensities with {approx}0.5% <span class="hlt">accuracy</span> and information on LSC efficiencies.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_13");'>13</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li class="active"><span>15</span></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_15 --> <div id="page_16" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="301"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2005AcAau..56..181J','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2005AcAau..56..181J"><span id="translatedtitle">In-flight quality and <span class="hlt">accuracy</span> of attitude measurements from the CHAMP advanced stellar compass</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Jørgensen, Peter S.; Jørgensen, John L.; Denver, Troelz; Betto, Maurizio</p> <p>2005-01-01</p> <p>The German geo-observations satellite CHAMP carries highly accurate vector instruments. The orientation of these relative to the inertial reference frame is obtained using star trackers. These advanced stellar compasses (ASC) are fully autonomous units, which provide, in real <span class="hlt">time</span>, the <span class="hlt">absolute</span> attitude with <span class="hlt">accuracy</span> in the arc second range. In order to investigate the in-flight <span class="hlt">accuracy</span> of the ASC, the terminology to characterize noise and biases is introduced. Relative instrument <span class="hlt">accuracy</span> (RIA) and <span class="hlt">absolute</span> instrument <span class="hlt">accuracy</span> (AIA) can in principle be determined in-flight. However problems with modeling external noise sources often arise. The special CHAMP configuration with two star tracker cameras mounted fixed together provides an excellent opportunity to determine the AIA in-flight using the inter boresight angle.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1227359','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1227359"><span id="translatedtitle"><span class="hlt">Absolute</span> nuclear material assay using count distribution (LAMBDA) space</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Prasad, Mano K.; Snyderman, Neal J.; Rowland, Mark S.</p> <p>2015-12-01</p> <p>A method of <span class="hlt">absolute</span> nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an <span class="hlt">absolute</span> nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an <span class="hlt">absolute</span> nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous <span class="hlt">time</span>-evolving sequence of event-counts by spreading the fission chain distribution in <span class="hlt">time</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1055713','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1055713"><span id="translatedtitle"><span class="hlt">Absolute</span> nuclear material assay using count distribution (LAMBDA) space</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.</p> <p>2012-06-05</p> <p>A method of <span class="hlt">absolute</span> nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an <span class="hlt">absolute</span> nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an <span class="hlt">absolute</span> nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous <span class="hlt">time</span>-evolving sequence of event-counts by spreading the fission chain distribution in <span class="hlt">time</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24110000','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24110000"><span id="translatedtitle">Investigation of the trade-off between <span class="hlt">time</span> window length, classifier update rate and classification <span class="hlt">accuracy</span> for restorative brain-computer interfaces.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Darvishi, Sam; Ridding, Michael C; Abbott, Derek; Baumert, Mathias</p> <p>2013-01-01</p> <p>Recently, the application of restorative brain-computer interfaces (BCIs) has received significant interest in many BCI labs. However, there are a number of challenges, that need to be tackled to achieve efficient performance of such systems. For instance, any restorative BCI needs an optimum trade-off between <span class="hlt">time</span> window length, classification <span class="hlt">accuracy</span> and classifier update rate. In this study, we have investigated possible solutions to these problems by using a dataset provided by the University of Graz, Austria. We have used a continuous wavelet transform and the Student t-test for feature extraction and a support vector machine (SVM) for classification. We find that improved results, for restorative BCIs for rehabilitation, may be achieved by using a 750 milliseconds <span class="hlt">time</span> window with an average classification <span class="hlt">accuracy</span> of 67% that updates every 32 milliseconds.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1044234','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1044234"><span id="translatedtitle">X-ray Streak Camera Cathode Development and <span class="hlt">Timing</span> <span class="hlt">Accuracy</span> of the 4w UV Fiducial System at the National Ignition Facility</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Opachich, Y P; Palmer, N; Homoelle, D; Hatch, B W; Bell, P; Bradley, D; Kalantar, D; Browning, D; Landen, O</p> <p>2012-05-02</p> <p>The convergent ablator experiments at the National Ignition Facility (NIF) are designed to measure the peak velocity and remaining ablator mass of an indirectly driven imploding capsule. Such a measurement can be performed using an x-ray source to backlight the capsule and an x-ray streak camera to record the capsule as it implodes. The ultimate goal of this experiment is to achieve an <span class="hlt">accuracy</span> of 2% in the velocity measurement, which translates to a {+-}2 ps temporal <span class="hlt">accuracy</span> over any 300 ps interval for the streak camera. In order to achieve this, a 4-{omega} (263nm) temporal fiducial system has been implemented for the x-ray streak camera at NIF. Aluminum, Titanium, Gold and Silver photocathode materials have been tested. Aluminum showed the highest quantum efficiency, with five <span class="hlt">times</span> more peak signal counts per fiducial pulse when compared to Gold. The fiducial pulse data was analyzed to determine the centroiding a statistical <span class="hlt">accuracy</span> for incident laser pulse energies of 1 and 10 nJ, showing an <span class="hlt">accuracy</span> of {+-}1.6 ps and {+-}0.7 ps respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=H+AND+36&pg=3&id=EJ1000510','ERIC'); return false;" href="http://eric.ed.gov/?q=H+AND+36&pg=3&id=EJ1000510"><span id="translatedtitle">Monitoring Ambulation of Patients in Geriatric Rehabilitation Wards: The <span class="hlt">Accuracy</span> of Clinicians' Prediction of Patients' Walking <span class="hlt">Time</span></span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Cheung, Vivian H. Y.; Salih, Salih A.; Crouch, Alisa; Karunanithi, Mohanraj K.; Gray, Len</p> <p>2012-01-01</p> <p>The aim of this study is to determine whether clinicians' estimates of patients' walking <span class="hlt">time</span> agree with those determined by accelerometer devices. The walking <span class="hlt">time</span> was measured using a waist-mounted accelerometer device everyday during the patients' waking hours. At each weekly meeting, clinicians estimated the patients' average daily walking…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=serial+AND+position+AND+effect&id=EJ735377','ERIC'); return false;" href="http://eric.ed.gov/?q=serial+AND+position+AND+effect&id=EJ735377"><span id="translatedtitle"><span class="hlt">Absolute</span> Identification by Relative Judgment</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Stewart, Neil; Brown, Gordon D. A.; Chater, Nick</p> <p>2005-01-01</p> <p>In unidimensional <span class="hlt">absolute</span> identification tasks, participants identify stimuli that vary along a single dimension. Performance is surprisingly poor compared with discrimination of the same stimuli. Existing models assume that identification is achieved using long-term representations of <span class="hlt">absolute</span> magnitudes. The authors propose an alternative…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=VALUE+AND+ABSOLUTE&id=EJ765743','ERIC'); return false;" href="http://eric.ed.gov/?q=VALUE+AND+ABSOLUTE&id=EJ765743"><span id="translatedtitle">Be Resolute about <span class="hlt">Absolute</span> Value</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Kidd, Margaret L.</p> <p>2007-01-01</p> <p>This article explores how conceptualization of <span class="hlt">absolute</span> value can start long before it is introduced. The manner in which <span class="hlt">absolute</span> value is introduced to students in middle school has far-reaching consequences for their future mathematical understanding. It begins to lay the foundation for students' understanding of algebra, which can change…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.G11B0924M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.G11B0924M"><span id="translatedtitle"><span class="hlt">Absolute</span> Antenna Calibration at the US National Geodetic Survey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mader, G. L.; Bilich, A. L.</p> <p>2012-12-01</p> <p>Geodetic GNSS applications routinely demand millimeter precision and extremely high levels of <span class="hlt">accuracy</span>. To achieve these <span class="hlt">accuracies</span>, measurement and instrument biases at the centimeter to millimeter level must be understood. One of these biases is the antenna phase center, the apparent point of signal reception for a GNSS antenna. It has been well established that phase center patterns differ between antenna models and manufacturers; additional research suggests that the addition of a radome or the choice of antenna mount can significantly alter those a priori phase center patterns. For the more demanding GNSS positioning applications and especially in cases of mixed-antenna networks, it is all the more important to know antenna phase center variations as a function of both elevation and azimuth in the antenna reference frame and incorporate these models into analysis software. Determination of antenna phase center behavior is known as "antenna calibration". Since 1994, NGS has computed relative antenna calibrations for more than 350 antennas. In recent years, the geodetic community has moved to <span class="hlt">absolute</span> calibrations - the IGS adopted <span class="hlt">absolute</span> antenna phase center calibrations in 2006 for use in their orbit and clock products, and NGS's CORS group began using <span class="hlt">absolute</span> antenna calibration upon the release of the new CORS coordinates in IGS08 epoch 2005.00 and NAD 83(2011,MA11,PA11) epoch 2010.00. Although NGS relative calibrations can be and have been converted to <span class="hlt">absolute</span>, it is considered best practice to independently measure phase center characteristics in an <span class="hlt">absolute</span> sense. Consequently, NGS has developed and operates an <span class="hlt">absolute</span> calibration system. These <span class="hlt">absolute</span> antenna calibrations accommodate the demand for greater <span class="hlt">accuracy</span> and for 2-dimensional (elevation and azimuth) parameterization. NGS will continue to provide calibration values via the NGS web site www.ngs.noaa.gov/ANTCAL, and will publish calibrations in the ANTEX format as well as the legacy ANTINFO</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010SPIE.7726E..0TL','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010SPIE.7726E..0TL"><span id="translatedtitle">Low cost varying synthetic wavelength technique for <span class="hlt">absolute</span> distance measurement</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Le Floch, S.; Salvadé, Y.</p> <p>2010-04-01</p> <p>A new low-cost superheterodyne configuration, without acousto-optic modulator, is applied to the two-wavelength interferometry for <span class="hlt">absolute</span> distance measurement. The principle relies on a synchronized frequency sweep of two optical signals, but with different frequency excursions. The frequency difference between the two optical waves is highly accurate. This is realized by injecting a frequency modulated laser signal in an intensity modulator that is biased at halfwave voltage and driven by a digitally swept radio-frequency signal between 13 and 15 GHz. This latter is a continuous up and down ramp. The two synchronized optical signals emerging from the modulator produce in a Michelson interferometer a distance dependent superheterodyne signal, with a variable synthetic wavelength of about 10 mm. The superheterodyne frequency depends linearly on distance and on the radio-frequency excursion. The integration <span class="hlt">time</span> for a distance measurement point corresponds to the duration of single sweep (i.e. one millisecond in our case). <span class="hlt">Absolute</span> distance measurements from 1 to 15 meters yield an <span class="hlt">accuracy</span> of +/-50 μm, showing the validity of the technique.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19770000329&hterms=MIDAS&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMIDAS','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19770000329&hterms=MIDAS&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3DMIDAS"><span id="translatedtitle">Classification <span class="hlt">accuracy</span> improvement</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kistler, R.; Kriegler, F. J.</p> <p>1977-01-01</p> <p>Improvements made in processing system designed for MIDAS (prototype multivariate interactive digital analysis system) effects higher <span class="hlt">accuracy</span> in classification of pixels, resulting in significantly-reduced processing <span class="hlt">time</span>. Improved system realizes cost reduction factor of 20 or more.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22230136','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22230136"><span id="translatedtitle">Evaluation of the <span class="hlt">accuracy</span> of articular cartilage thickness measurement by B-mode ultrasonography with conventional imaging and real-<span class="hlt">time</span> spatial compound ultrasonography imaging.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ohashi, Satoru; Ohnishi, Isao; Matsumoto, Takuya; Bessho, Masahiko; Matsuyama, Juntaro; Tobita, Kenji; Kaneko, Masako; Nakamura, Kozo</p> <p>2012-02-01</p> <p>The present study aimed to quantify the thickness of articular cartilage (Tc) in vitro using both conventional and real-<span class="hlt">time</span> spatial compound B-mode ultrasonography (US) with a clinically used transducer and to evaluate the <span class="hlt">accuracy</span> of measurement by comparing the results with values obtained microscopically. Femoral condyle samples were obtained from a 6-month-old pig and a 3-year-old pig. B-mode US images with conventional imaging and real-<span class="hlt">time</span> spatial compound imaging (RTSCI) of osteochondral blocks were acquired. Tc determined using US (Tc-US) was measured from line data parallel to US beam direction acquired from B-mode images with an objective method for determining cartilage surface and bone-cartilage interfaces at the peak brightness values. Tc was also determined under microscopy (Tc-optical) using the corresponding points from US measurement. Tc-US was compared with Tc-optical to assess <span class="hlt">accuracy</span>. Tc-US correlated significantly with Tc in both conventional imaging and RTSCI (r = 0.961, 0.976, respectively). Bland-Altman plots showed mean differences between Tc-optical and Tc-US were -0.0073 mm and 0.0139 mm with standard deviations of 0.171 mm and 0.131 mm for conventional imaging and RTSCI, respectively. Our results show that Tc-US measurement using B-mode US allows accurate measurement of Tc. Considering correlation coefficients between Tc-US and Tc-optical, RTSCI US may offer higher <span class="hlt">accuracy</span> for measuring Tc than conventional methods when an objective tissue border determination algorithm is used, even though both showed good <span class="hlt">accuracy</span> in our study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2003MmSAI..74..884C','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2003MmSAI..74..884C"><span id="translatedtitle">The Carina Project: <span class="hlt">Absolute</span> and Relative Calibrations</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Corsi, C. E.; Bono, G.; Walker, A. R.; Brocato, E.; Buonanno, R.; Caputo, F.; Castellani, M.; Castellani, V.; Dall'Ora, M.; Marconi, M.; Monelli, M.; Nonino, M.; Pulone, L.; Ripepi, V.; Smith, H. A.</p> <p></p> <p>We discuss the reduction strategy adopted to perform the relative and the <span class="hlt">absolute</span> calibration of the Wide Field Imager (WFI) available at the 2.2m ESO/MPI telescope and of the Mosaic Camera (MC) available at the 4m CTIO Blanco telescope. To properly constrain the occurrence of deceptive systematic errors in the relative calibration we observed with each chip the same set of stars. Current photometry seems to suggest that the WFI shows a positional effect when moving from the top to the bottom of individual chips. Preliminary results based on an independent data set collected with the MC suggest that this camera is only marginally affected by the same problem. To perform the <span class="hlt">absolute</span> calibration we observed with each chip the same set of standard stars. The sample covers a wide color range and the <span class="hlt">accuracy</span> both in the B and in the V-band appears to be of the order of a few hundredths of magnitude. Finally, we briefly outline the observing strategy to improve both relative and <span class="hlt">absolute</span> calibrations of mosaic CCD cameras.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2002AGUFMOS52A0201L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2002AGUFMOS52A0201L"><span id="translatedtitle"><span class="hlt">Accuracy</span> Assessment of Altimeter Derived Geostrophic Velocities</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leben, R. R.; Powell, B. S.; Born, G. H.; Guinasso, N. L.</p> <p>2002-12-01</p> <p>Along track sea surface height anomaly gradients are proportional to cross track geostrophic velocity anomalies allowing satellite altimetry to provide much needed satellite observations of changes in the geostrophic component of surface ocean currents. Often, surface height gradients are computed from altimeter data archives that have been corrected to give the most accurate <span class="hlt">absolute</span> sea level, a practice that may unnecessarily increase the error in the cross track velocity anomalies and thereby require excessive smoothing to mitigate noise. Because differentiation along track acts as a high-pass filter, many of the path length corrections applied to altimeter data for <span class="hlt">absolute</span> height <span class="hlt">accuracy</span> are unnecessary for the corresponding gradient calculations. We report on a study to investigate appropriate altimetric corrections and processing techniques for improving geostrophic velocity <span class="hlt">accuracy</span>. <span class="hlt">Accuracy</span> is assessed by comparing cross track current measurements from two moorings placed along the descending TOPEX/POSEIDON ground track number 52 in the Gulf of Mexico to the corresponding altimeter velocity estimates. The buoys are deployed and maintained by the Texas Automated Buoy System (TABS) under Interagency Contracts with Texas A&M University. The buoys telemeter observations in near real-<span class="hlt">time</span> via satellite to the TABS station located at the Geochemical and Environmental Research Group (GERG) at Texas A&M. Buoy M is located in shelf waters of 57 m depth with a second, Buoy N, 38 km away on the shelf break at 105 m depth. Buoy N has been operational since the beginning of 2002 and has a current meter at 2m depth providing in situ measurements of surface velocities coincident with Jason and TOPEX/POSEIDON altimeter over flights. This allows one of the first detailed comparisons of shallow water near surface current meter <span class="hlt">time</span> series to coincident altimetry.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27034831','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27034831"><span id="translatedtitle">Diffusion-Weighted Imaging with Color-Coded Images: Towards a Reduction in Reading <span class="hlt">Time</span> While Keeping a Similar <span class="hlt">Accuracy</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Campos Kitamura, Felipe; de Medeiros Alves, Srhael; Antônio Tobaru Tibana, Luis; Abdala, Nitamar</p> <p>2016-01-01</p> <p>The aim of this study was to develop a diagnostic tool capable of providing diffusion and apparent diffusion coefficient (ADC) map information in a single color-coded image and to assess the performance of color-coded images compared with their corresponding diffusion and ADC map. The institutional review board approved this retrospective study, which sequentially enrolled 36 head MRI scans. Diffusion-weighted images (DWI) and ADC maps were compared to their corresponding color-coded images. Four raters had their interobserver agreement measured for both conventional (DWI) and color-coded images. Differences between conventional and color-coded images were also estimated for each of the 4 raters. Cohen's kappa and percent agreement were used. Also, paired-samples t-test was used to compare reading <span class="hlt">time</span> for rater 1. Conventional and color-coded images had substantial or almost perfect agreement for all raters. Mean reading <span class="hlt">time</span> of rater 1 was 47.4 seconds for DWI and 27.9 seconds for color-coded images (P = .00007). These findings are important because they support the role of color-coded images as being equivalent to that of the conventional DWI in terms of diagnostic capability. Reduction in reading <span class="hlt">time</span> (which makes the reading easier) is also demonstrated for one rater in this study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19950025918','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19950025918"><span id="translatedtitle">Prospects for high <span class="hlt">accuracy</span> <span class="hlt">time</span> dissemination and synchronization using coded radar pulses from a low-earth orbiting spacecraft</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Detoma, Edoardo V.; Dionisio, C.</p> <p>1995-01-01</p> <p>The radar (an acronym for radio detection and ranging) is an instrument developed just before the WW-II to precisely measure the position of an object (target) in space. This is done by emitting a narrow pulse of electromagnetic energy in the RF spectrum, receiving the return echo and measuring the <span class="hlt">time</span> of flight in the two-way path from the emitter to the target. The propagation delay provides a measure of the range to the target, which is not in itself sufficient to uniquely locate the position of the same in space. However, if a directional antenna is used, the direction of the echo can be assessed by the antenna pointing angles. In this way the position of the target can be uniquely determined in space. How well this can be done is a function of the resolution of the measurements performed (range and direction, i.e.: angles); in turn, the resolution will dictate the <span class="hlt">time</span> and frequency requirements of the reference oscillator.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4663807','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4663807"><span id="translatedtitle">Effectiveness of slow motion video compared to real <span class="hlt">time</span> video in improving the <span class="hlt">accuracy</span> and consistency of subjective gait analysis in dogs</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Lane, D.M.; Hill, S.A.; Huntingford, J.L.; Lafuente, P.; Wall, R.; Jones, K.A.</p> <p>2015-01-01</p> <p>Objective measures of canine gait quality via force plates, pressure mats or kinematic analysis are considered superior to subjective gait assessment (SGA). Despite research demonstrating that SGA does not accurately detect subtle lameness, it remains the most commonly performed diagnostic test for detecting lameness in dogs. This is largely because the financial, temporal and spatial requirements for existing objective gait analysis equipment makes this technology impractical for use in general practice. The utility of slow motion video as a potential tool to augment SGA is currently untested. To evaluate a more accessible way to overcome the limitations of SGA, a slow motion video study was undertaken. Three experienced veterinarians reviewed video footage of 30 dogs, 15 with a diagnosis of primary limb lameness based on history and physical examination, and 15 with no indication of limb lameness based on history and physical examination. Four different videos were made for each dog, demonstrating each dog walking and trotting in real <span class="hlt">time</span>, and then again walking and trotting in 50% slow motion. For each video, the veterinary raters assessed both the degree of lameness, and which limb(s) they felt represented the source of the lameness. Spearman’s rho, Cramer’s V, and t-tests were performed to determine if slow motion video increased either the <span class="hlt">accuracy</span> or consistency of raters’ SGA relative to real <span class="hlt">time</span> video. Raters demonstrated no significant increase in consistency or <span class="hlt">accuracy</span> in their SGA of slow motion video relative to real <span class="hlt">time</span> video. Based on these findings, slow motion video does not increase the consistency or <span class="hlt">accuracy</span> of SGA values. Further research is required to determine if slow motion video will benefit SGA in other ways. PMID:26623383</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.V14B..02S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.V14B..02S"><span id="translatedtitle">Progress integrating ID-TIMS U-Pb geochronology with accessory mineral geochemistry: towards better <span class="hlt">accuracy</span> and higher precision <span class="hlt">time</span></span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Schoene, B.; Samperton, K. M.; Crowley, J. L.; Cottle, J. M.</p> <p>2012-12-01</p> <p>It is increasingly common that hand samples of plutonic and volcanic rocks contain zircon with dates that span between zero and >100 ka. This recognition comes from the increased application of U-series geochronology on young volcanic rocks and the increased precision to better than 0.1% on single zircons by the U-Pb ID-TIMS method. It has thus become more difficult to interpret such complicated datasets in terms of ashbed eruption or magma emplacement, which are critical constraints for geochronologic applications ranging from biotic evolution and the stratigraphic record to magmatic and metamorphic processes in orogenic belts. It is important, therefore, to develop methods that aid in interpreting which minerals, if any, date the targeted process. One promising tactic is to better integrate accessory mineral geochemistry with high-precision ID-TIMS U-Pb geochronology. These dual constraints can 1) identify cogenetic populations of minerals, and 2) record magmatic or metamorphic fluid evolution through <span class="hlt">time</span>. Goal (1) has been widely sought with in situ geochronology and geochemical analysis but is limited by low-precision dates. Recent work has attempted to bridge this gap by retrieving the typically discarded elution from ion exchange chemistry that precedes ID-TIMS U-Pb geochronology and analyzing it by ICP-MS (U-Pb TIMS-TEA). The result integrates geochemistry and high-precision geochronology from the exact same volume of material. The limitation of this method is the relatively coarse spatial resolution compared to in situ techniques, and thus averages potentially complicated trace element profiles through single minerals or mineral fragments. In continued work, we test the effect of this on zircon by beginning with CL imaging to reveal internal zonation and growth histories. This is followed by in situ LA-ICPMS trace element transects of imaged grains to reveal internal geochemical zonation. The same grains are then removed from grain-mount, fragmented, and</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22811242','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22811242"><span id="translatedtitle">Clock <span class="hlt">accuracy</span> and precision evolve as a consequence of selection for adult emergence in a narrow window of <span class="hlt">time</span> in fruit flies Drosophila melanogaster.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kannan, Nisha N; Vaze, Koustubh M; Sharma, Vijay Kumar</p> <p>2012-10-15</p> <p>Although circadian clocks are believed to have evolved under the action of periodic selection pressures (selection on phasing) present in the geophysical environment, there is very little rigorous and systematic empirical evidence to support this. In the present study, we examined the effect of selection for adult emergence in a narrow window of <span class="hlt">time</span> on the circadian rhythms of fruit flies Drosophila melanogaster. Selection was imposed in every generation by choosing flies that emerged during a 1 h window of <span class="hlt">time</span> close to the emergence peak of baseline/control flies under 12 h:12 h light:dark cycles. To study the effect of selection on circadian clocks we estimated several quantifiable features that reflect inter- and intra-individual variance in adult emergence and locomotor activity rhythms. The results showed that with increasing generations, incidence of adult emergence and activity of adult flies during the 1 h selection window increased gradually in the selected populations. Flies from the selected populations were more homogenous in their clock period, were more coherent in their phase of entrainment, and displayed enhanced <span class="hlt">accuracy</span> and precision in their emergence and activity rhythms compared with controls. These results thus suggest that circadian clocks in D. melanogaster evolve enhanced <span class="hlt">accuracy</span> and precision when subjected to selection for emergence in a narrow window of <span class="hlt">time</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4338538','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4338538"><span id="translatedtitle">Camera-based three-dimensional real-<span class="hlt">time</span> particle tracking at kHz rates and Ångström <span class="hlt">accuracy</span></span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Daldrop, Peter; Joo, Sihwa; Otto, Oliver; Keyser, Ulrich F.; Seidel, Ralf</p> <p>2014-01-01</p> <p>Optical and magnetic tweezers are widely employed to probe the mechanics and activity of individual biomolecular complexes. They rely on micrometer-sized particles to detect molecular conformational changes from the particle position. Real-<span class="hlt">time</span> particle tracking with Ångström <span class="hlt">accuracy</span> has so far been only achieved using laser detection through photodiodes. Here we demonstrate that camera-based imaging can provide a similar performance for all three dimensions. Particle imaging at kHz rates is combined with real-<span class="hlt">time</span> data processing being accelerated by a graphics processing unit. For particles that are fixed in the sample cell we can detect 3 Å sized steps that are introduced by cell translations at rates of 10 Hz, while for DNA-tethered particles 5 Å steps at 1 Hz can be resolved. Moreover, 20 particles can be tracked in parallel with comparable <span class="hlt">accuracy</span>. Our approach provides a simple and robust way for high-resolution tweezers experiments using multiple particles at a <span class="hlt">time</span>. PMID:25565216</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_14");'>14</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li class="active"><span>16</span></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_16 --> <div id="page_17" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="321"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4940374','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4940374"><span id="translatedtitle">Effects of Age and Task Load on Drivers’ Response <span class="hlt">Accuracy</span> and Reaction <span class="hlt">Time</span> When Responding to Traffic Lights</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Salvia, Emilie; Petit, Claire; Champely, Stéphane; Chomette, René; Di Rienzo, Franck; Collet, Christian</p> <p>2016-01-01</p> <p>Due to population aging, elderly drivers represent an increasing proportion of car drivers. Yet, how aging alters sensorimotor functions and impacts driving safety remains poorly understood. This paper aimed at assessing to which extent elderly drivers are sensitive to various task loads and how this affects the reaction <span class="hlt">time</span> (RT) in a driving context. Old and middle-aged people completed RT tasks which reproduced cognitive demands encountered while driving. Participants had to detect and respond to traffic lights or traffic light arrows as quickly as possible, under three experimental conditions of incremental difficulty. In both groups, we hypothesized that decision-making would be impacted by the number of cues to be processed. The first test was a simple measure of RT. The second and third tests were choice RT tasks requiring the processing of 3 and 5 cues, respectively. Responses were collected within a 2 s <span class="hlt">time</span>-window. Otherwise, the trial was considered a no-response. In both groups, the data revealed that RT, error rate (incorrect answers), and no-response rate increased along with task difficulty. However, the middle-aged group outperformed the elderly group. The RT difference between the two groups increased drastically along with task difficulty. In the third test, the rate of no-response suggested that elderly drivers needed more than 2 s to process complex information and respond accurately. Both prolonged RT and increased no-response rate, especially for difficult tasks, might attest an impairment of cognitive abilities in relation to aging. Accordingly, casual driving conditions for young drivers may be particularly complex and stressful for elderly people who should thus be informed about the effects of normal aging upon driving. PMID:27462266</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27462490','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27462490"><span id="translatedtitle">An improved generalized Newton method for <span class="hlt">absolute</span> value equations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Feng, Jingmei; Liu, Sanyang</p> <p>2016-01-01</p> <p>In this paper, we suggest and analyze an improved generalized Newton method for solving the NP-hard <span class="hlt">absolute</span> value equations [Formula: see text] when the singular values of A exceed 1. We show that the global and local quadratic convergence of the proposed method. Numerical experiments show the efficiency of the method and the high <span class="hlt">accuracy</span> of calculation. PMID:27462490</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19720059878&hterms=rights+author&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Drights%2Bauthor','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19720059878&hterms=rights+author&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Drights%2Bauthor"><span id="translatedtitle">Singular perturbation of <span class="hlt">absolute</span> stability.</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Siljak, D. D.</p> <p>1972-01-01</p> <p>It was previously shown (author, 1969) that the regions of <span class="hlt">absolute</span> stability in the parameter space can be determined when the parameters appear on the right-hand side of the system equations, i.e., the regular case. Here, the effect on <span class="hlt">absolute</span> stability of a small parameter attached to higher derivatives in the equations (the singular case) is studied. The Lur'e-Postnikov class of nonlinear systems is considered.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26717367','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26717367"><span id="translatedtitle">Comparison of Diagnostic <span class="hlt">Accuracy</span> of Real-<span class="hlt">Time</span> Elastography and Shear Wave Elastography in Differentiation Malignant From Benign Thyroid Nodules.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Tian, Wuguo; Hao, Shuai; Gao, Bo; Jiang, Yan; Zhang, Shu; Guo, Lingji; Gu, Lingji; Luo, Donglin</p> <p>2015-12-01</p> <p>Thyroid nodules are relatively more prevalent in iodine-deficiency area, and the incidence increased sharply in the past decade in these areas. Workup of malignant from benign nodules in clinic was the main problem for managing thyroid nodules.An overall search for the articles about the diagnostic performance of real-<span class="hlt">time</span> elastography (RTE) and shear wave elastography (SWE) before April 2015 in the databases of PubMed, Embase, and Google scholar. The pooled sensitivity, specificity, and summary receiver operating characteristic (SROC) curve were obtained from individual studies with a random-effects model. Subgroup and meta-regression analysis were also performed.Fifty-six studies involved in 2621 malignant nodules and 7380 benign nodules were contained in our meta-analysis. The pooled sensitivity and specificity of RTE was 83.0% and 81.2%, which is higher than SWE (sensitivity: 78.7%, specificity: 80.5%). The areas under the SROC curve of RTE and SWE were 0.885 and 0.842 respectively. RTE had higher diagnostic value for Caucasians than Asians. Stran ratio (SR) assessment had higher diagnostic performance than elasticity score (ES) system. Similarly, it had higher diagnostic value when malignant nodules were more than 50.In summary, the results revealed that RTE had higher diagnostic performance than SWE in differentiating malignant from benign nodules. However, future international multicenter studies in the region of thyroid risk need to further assess the diagnostic performance of RTE. PMID:26717367</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24829234','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24829234"><span id="translatedtitle"><span class="hlt">Accuracy</span> of matrix-assisted laser desorption ionization-<span class="hlt">time</span> of flight mass spectrometry for identification of clinical pathogenic fungi: a meta-analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Ling, Huazhi; Yuan, Zhijie; Shen, Jilu; Wang, Zhongxin; Xu, Yuanhong</p> <p>2014-07-01</p> <p>Fungal infections in the clinic have become increasingly serious. In many cases, the identification of clinically relevant fungi remains <span class="hlt">time</span>-consuming and may also be unreliable. Matrix-assisted laser desorption ionization-<span class="hlt">time</span> of flight mass spectroscopy (MALDI-TOF MS) is a newly developed diagnostic tool that is increasingly being employed to rapidly and accurately identify clinical pathogenic microorganisms. The present meta-analysis aimed to systematically evaluate the <span class="hlt">accuracy</span> of MALDI-TOF MS for the identification of clinical pathogenic fungi. After a rigorous selection process, 33 articles, involving 38 trials and a total of 9,977 fungal isolates, were included in the meta-analysis. The random-effects pooled identification <span class="hlt">accuracy</span> of MALDI-TOF MS increased from 0.955 (95% confidence interval [CI], 0.939 to 0.969) at the species level to 0.977 (95% CI, 0.955 to 0.993) at the genus level (P < 0.001; χ(2) = 15.452). Subgroup analyses were performed at the species level for several categories, including strain, source of strain, system, system database, and modified outcomes, to calculate the <span class="hlt">accuracy</span> and to investigate heterogeneity. These analyses revealed significant differences between the overall meta-analysis and some of the subanalyses. In parallel, significant differences in heterogeneity among different systems and among different methods for calculating the identification ratios were found by multivariate metaregression, but none of the factors, except for the moderator of outcome, was significantly associated with heterogeneity by univariate metaregression. In summary, the MALDI-TOF MS method is highly accurate for the identification of clinically pathogenic fungi; future studies should analyze the comprehensive capability of this technology for clinical diagnostic microbiology.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110015245','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110015245"><span id="translatedtitle">Calibration of the Reflected Solar Instrument for the Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thome, Kurtis; Barnes, Robert; Baize, Rosemary; O'Connell, Joseph; Hair, Jason</p> <p>2010-01-01</p> <p>The Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory (CLARREO) plans to observe climate change trends over decadal <span class="hlt">time</span> scales to determine the <span class="hlt">accuracy</span> of climate projections. The project relies on spaceborne earth observations of SI-traceable variables sensitive to key decadal change parameters. The mission includes a reflected solar instrument retrieving at-sensor reflectance over the 320 to 2300 nm spectral range with 500-m spatial resolution and 100-km swath. Reflectance is obtained from the ratio of measurements of the earth s surface to those while viewing the sun relying on a calibration approach that retrieves reflectance with uncertainties less than 0.3%. The calibration is predicated on heritage hardware, reduction of sensor complexity, adherence to detector-based calibration standards, and an ability to simulate in the laboratory on-orbit sources in both size and brightness to provide the basis of a transfer to orbit of the laboratory calibration including a link to <span class="hlt">absolute</span> solar irradiance measurements.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/5184149','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/5184149"><span id="translatedtitle"><span class="hlt">Absolutely</span> calibrated soft-x-ray streak camera for laser-fusion applications</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kauffman, R.L.; Medecki, H.; Stradling, G.</p> <p>1982-01-01</p> <p>The intensity output of a soft-x-ray streak camera was calibrated (SXRSC) in order to make <span class="hlt">absolute</span> flux measurements of x rays emitted from laser-produced plasmas. The SXRSC developed at LLNL is used to <span class="hlt">time</span>-resolve x-ray pulses to better than 20 ps. The SXRSC uses a Au photocathode on a thin carbon substrate which is sensitive to x rays from 100 eV to greater than 10 keV. Calibrations are done in the dynamic mode using a small laser-produced x-ray source. The SXRSC is calibrated by comparing its integrated signal to the output of calibrated x-ray diodes monitoring the source strength. The measured SXRSC response is linear over greater than two orders of magnitude. Using these calibrations, <span class="hlt">absolute</span> intensities can be measured to an <span class="hlt">accuracy</span> of +-30%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22058693','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22058693"><span id="translatedtitle">High <span class="hlt">accuracy</span> wavelength calibration for a scanning visible spectrometer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Scotti, Filippo; Bell, Ronald E.</p> <p>2010-10-15</p> <p>Spectroscopic applications for plasma velocity measurements often require wavelength <span class="hlt">accuracies</span> {<=}0.2 A. An automated calibration, which is stable over <span class="hlt">time</span> and environmental conditions without the need to recalibrate after each grating movement, was developed for a scanning spectrometer to achieve high wavelength <span class="hlt">accuracy</span> over the visible spectrum. This method fits all relevant spectrometer parameters using multiple calibration spectra. With a stepping-motor controlled sine drive, an <span class="hlt">accuracy</span> of {approx}0.25 A has been demonstrated. With the addition of a high resolution (0.075 arc sec) optical encoder on the grating stage, greater precision ({approx}0.005 A) is possible, allowing <span class="hlt">absolute</span> velocity measurements within {approx}0.3 km/s. This level of precision requires monitoring of atmospheric temperature and pressure and of grating bulk temperature to correct for changes in the refractive index of air and the groove density, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/984472','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/984472"><span id="translatedtitle">High <span class="hlt">Accuracy</span> Wavelength Calibration For A Scanning Visible Spectrometer</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Filippo Scotti and Ronald Bell</p> <p>2010-07-29</p> <p>Spectroscopic applications for plasma velocity measurements often require wavelength <span class="hlt">accuracies</span> ≤ 0.2Â. An automated calibration for a scanning spectrometer has been developed to achieve a high wavelength <span class="hlt">accuracy</span> overr the visible spectrum, stable over <span class="hlt">time</span> and environmental conditions, without the need to recalibrate after each grating movement. The method fits all relevant spectrometer paraameters using multiple calibration spectra. With a steping-motor controlled sine-drive, <span class="hlt">accuracies</span> of ~0.025  have been demonstrated. With the addition of high resolution (0.075 aresec) optical encoder on the grading stage, greater precision (~0.005 Â) is possible, allowing <span class="hlt">absolute</span> velocity measurements with ~0.3 km/s. This level of precision requires monitoring of atmospheric temperature and pressure and of grating bulk temperature to correct for changes in the refractive index of air and the groove density, respectively.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22351072','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22351072"><span id="translatedtitle">SU-E-T-248: Near Real-<span class="hlt">Time</span> Analysis of Radiation Delivery and Imaging, <span class="hlt">Accuracy</span> to Ensure Patient Safety</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Wijesooriya, K; Seitter, K; Desai, V; Read, P; Larner, J</p> <p>2014-06-01</p> <p>Purpose: To develop and optimize an effective software method for comparing planned to delivered control point machine parameters for all VARIAN TrueBeam treatments so as to permit (1) assessment of a large patient pool throughout their treatment course to quantify treatment technique specific systematic and random uncertainty of observables, (2) quantify the site specific daily imaging shifts required for target alignment, and (3) define tolerance levels for mechanical parameters and imaging parameters based on statistical analysis data gathered, and the dosimetric impact of variations. Methods: Treatment and imaging log files were directly compared to plan parameters for Eclipse and Pinnacle planned treatments via 3D, IMRT, control point, RapidArc, and electrons. Each control point from all beams/arcs (7984) for all fractions (1940) of all patients treated over six months were analyzed. At each control point gantry angle, collimator angle, couch angle, jaw positions, MLC positions, MU were compared. Additionally per-treatment isocenter shifts were calculated. Results were analyzed as a whole in treatment type subsets: IMRT, 3D, RapidArc; and in treatment site subsets: brain, chest/mediastinum, esophagus, H and N, lung, pelvis, prostate. Results: Daily imaging isocenter shifts from initial external tattoo alignment were dependent on the treatment site with < 0.5 cm translational shifts for H and N, Brain, and lung SBRT, while pelvis, esophagus shifts were ∼1 cm. Mechanical delivery parameters were within tolerance levels for all sub-beams. The largest variations were for RapidArc plans: gantry angle 0.11±0.12,collimator angle 0.00±0.00, jaw positions 0.48±0.26, MLC leaf positions 0.66±0.08, MU 0.14±0.34. Conclusion: Per-control point validation reveals deviations between planned and delivered parameters. If used in a near real-<span class="hlt">time</span> error checking system, patient safety can be improved by equipping the treatment delivery system with additional forcing</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22218327','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22218327"><span id="translatedtitle">A general strategy for performing temperature-programming in high performance liquid chromatography--further improvements in the <span class="hlt">accuracy</span> of retention <span class="hlt">time</span> predictions of segmented temperature gradients.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wiese, Steffen; Teutenberg, Thorsten; Schmidt, Torsten C</p> <p>2012-01-27</p> <p>In the present work it is shown that the linear elution strength (LES) model which was adapted from temperature-programming gas chromatography (GC) can also be employed for systematic method development in high-temperature liquid chromatography (HT-HPLC). The ability to predict isothermal retention <span class="hlt">times</span> based on temperature-gradient as well as isothermal input data was investigated. For a small temperature interval of ΔT=40°C, both approaches result in very similar predictions. Average relative errors of predicted retention <span class="hlt">times</span> of 2.7% and 1.9% were observed for simulations based on isothermal and temperature-gradient measurements, respectively. Concurrently, it was investigated whether the <span class="hlt">accuracy</span> of retention <span class="hlt">time</span> predictions of segmented temperature gradients can be further improved by temperature dependent calculation of the parameter S(T) of the LES relationship. It was found that the <span class="hlt">accuracy</span> of retention <span class="hlt">time</span> predictions of multi-step temperature gradients can be improved to around 1.5%, if S(T) was also calculated temperature dependent. The adjusted experimental design making use of four temperature-gradient measurements was applied for systematic method development of selected food additives by high-temperature liquid chromatography. Method development was performed within a temperature interval from 40°C to 180°C using water as mobile phase. Two separation methods were established where selected food additives were baseline separated. In addition, a good agreement between simulation and experiment was observed, because an average relative error of predicted retention <span class="hlt">times</span> of complex segmented temperature gradients less than 5% was observed. Finally, a schedule of recommendations to assist the practitioner during systematic method development in high-temperature liquid chromatography was established.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12873123','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12873123"><span id="translatedtitle">Effect of processing variables (different compression packing processes and investment material types) and <span class="hlt">time</span> on the dimensional <span class="hlt">accuracy</span> of polymethyl methacrylate denture bases.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Baydas, Seyfettin; Bayindir, Funda; Akyil, M Samil</p> <p>2003-06-01</p> <p>In this study we determined the effect of different compression packing processes, investment materials (a hemihydrate and dental stone) and <span class="hlt">time</span> on the dimensional <span class="hlt">accuracy</span> of polymethyl metacrylate denture bases. Square stainless steel plates (15 mm x 15 mm x 5 mm) were prepared to make an acrylic resin specimen. The linear dimensional changes of acrylic resin were determined by measuring the distances of fix points. Measurements were made at 24 hours, 48 hours, 12 days and 30 days after setting with a digital compass. Dimensional changes of test specimens that were obtained with three different flasks and two press techniques were compared by univariate analysis. Measurements of the linear dimensions of specimens cured by different compression packing techniques suggested that differences existed. The <span class="hlt">time</span> interval differences were not significant. According to the results; flask and investment material types affect the dimensional <span class="hlt">accuracy</span> of test specimens (p < 0.05). The least dimensional change observed in the specimens was obtained with Type 1 flask-dental stone-manual press combinations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/12112258','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/12112258"><span id="translatedtitle">A simple algorithm improves mass <span class="hlt">accuracy</span> to 50-100 ppm for delayed extraction linear matrix-assisted laser desorption/ionization <span class="hlt">time</span>-of-flight mass spectrometry.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Hack, Christopher A; Benner, W Henry</p> <p>2002-01-01</p> <p>A simple mathematical technique for improving mass calibration <span class="hlt">accuracy</span> of linear delayed extraction matrix-assisted laser desorption/ionization <span class="hlt">time</span>-of-flight mass spectrometry (DE MALDI-TOFMS) spectra is presented. The method involves fitting a parabola to a plot of Delta(m) vs. mass data where Delta(m) is the difference between the theoretical mass of calibrants and the mass obtained from a linear relationship between the square root of m/z and ion <span class="hlt">time</span> of flight. The quadratic equation that describes the parabola is then used to correct the mass of unknowns by subtracting the deviation predicted by the quadratic equation from measured data. By subtracting the value of the parabola at each mass from the calibrated data, the <span class="hlt">accuracy</span> of mass data points can be improved by factors of 10 or more. This method produces highly similar results whether or not initial ion velocity is accounted for in the calibration equation; consequently, there is no need to depend on that uncertain parameter when using the quadratic correction. This method can be used to correct the internally calibrated masses of protein digest peaks. The effect of nitrocellulose as a matrix additive is also briefly discussed, and it is shown that using nitrocellulose as an additive to the alpha-cyano-4-hydroxycinnamic acid (alphaCHCA) matrix does not significantly change initial ion velocity but does change the average position of ions relative to the sample electrode at the instant the extraction voltage is applied.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25569889','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25569889"><span id="translatedtitle">The effect of window size and lead <span class="hlt">time</span> on pre-impact fall detection <span class="hlt">accuracy</span> using support vector machine analysis of waist mounted inertial sensor data.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Aziz, Omar; Russell, Colin M; Park, Edward J; Robinovitch, Stephen N</p> <p>2014-01-01</p> <p>Falls are a major cause of death and morbidity in older adults. In recent years many researchers have examined the role of wearable inertial sensors (accelerometers and/or gyroscopes) to automatically detect falls. The primary goal of such fall monitors is to alert care providers of the fall event, who can then commence earlier treatment. Although such fall detection systems may reduce <span class="hlt">time</span> until the arrival of medical assistance, they cannot help to prevent or reduce the severity of traumatic injury caused by the fall. In the current study, we extend the application of wearable inertial sensors beyond post-impact fall detection, by developing and evaluating the <span class="hlt">accuracy</span> of a sensor system for detecting falls prior to the fall impact. We used support vector machine (SVM) analysis to classify 7 fall and 8 non-fall events. In particular, we focused on the effect of data window size and lead <span class="hlt">time</span> on the <span class="hlt">accuracy</span> of our pre-impact fall detection system using signals from a single waist sensor. We found that our system was able to detect fall events at between 0.0625-0.1875 s prior to the impact with at least 95% sensitivity and at least 90% specificity for window sizes between 0.125-1 s.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4201312','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4201312"><span id="translatedtitle">A Clinical Trial of the <span class="hlt">Accuracy</span> and Treatment Experience of the Dexcom G4 Sensor (Dexcom G4 System) and Enlite Sensor (Guardian REAL-<span class="hlt">Time</span> System) Tested Simultaneously in Ambulatory Patients with Type 1 Diabetes</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Matuleviciene, Viktorija; Joseph, Jeffrey I.; Andelin, Mervi; Hirsch, Irl B.; Attvall, Stig; Pivodic, Aldina; Dahlqvist, Sofia; Klonoff, David; Haraldsson, Börje</p> <p>2014-01-01</p> <p>Abstract Background: Continuous glucose monitoring (CGM) is a tool widely used in the treatment of patients with type 1 diabetes. The purpose of the current study was to evaluate whether <span class="hlt">accuracy</span> and patient treatment satisfaction differ between the Enlite™ (Medtronic MiniMed, Inc., Northridge, CA) and Dexcom® (San Diego, CA) G4 PLATINUM CGM sensors. Subjects and Methods: Thirty-eight ambulatory patients with type 1 diabetes used the Dexcom G4 and Enlite sensors simultaneously for a minimum of 4 and maximum of 6 days. Patients measured capillary glucose levels with a HemoCue® (Ängelholm, Sweden) system six to 10 <span class="hlt">times</span> a day. In addition, two inpatient studies were performed between Days 1–3 and 4–6. Results: The mean <span class="hlt">absolute</span> relative difference (MARD) in blood glucose for the Dexcom G4 was significantly lower (13.9%) than for the Enlite sensor (17.8%) (P<0.0001). The corresponding MARDs for Days 1–3 were 15.0% versus 19.4% (P=0.0027) and 13.6% versus 15.9% (P=0.026) for Days 4–6. For glucose levels in the hypoglycemic range (<4.0 mmol/L), the MARD for the Dexcom G4 was 20.0% compared with 34.7% for the Enlite (P=0.0041). On a visual analog scale (VAS) (0–100), patients rated the Dexcom G4 more favorably than the Enlite in 12 out of the 13 user experience questions. For example, more patients rated their experience with the Dexcom G4 as positive (VAS, 79.7 vs. 46.6; P<0.0001) and preferred to use it in their daily lives (VAS, 79.1 vs. 42.1; P<0.0001). Conclusions: The Dexcom G4 sensor was associated with greater overall <span class="hlt">accuracy</span> than the Enlite sensor during initial (Days 1–3) and later (Days 4–6) use and for glucose levels in the hypoglycemic range. Patients reported a significantly more positive experience using the Dexcom G4 than the Enlite. PMID:25233297</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016Metro..53..754N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016Metro..53..754N"><span id="translatedtitle">Improving <span class="hlt">absolute</span> gravity estimates by the L p -norm approximation of the ballistic trajectory</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nagornyi, V. D.; Svitlov, S.; Araya, A.</p> <p>2016-04-01</p> <p>Iteratively re-weighted least squares (IRLS) were used to simulate the L p -norm approximation of the ballistic trajectory in <span class="hlt">absolute</span> gravimeters. Two iterations of the IRLS delivered sufficient <span class="hlt">accuracy</span> of the approximation without a significant bias. The simulations were performed on different samplings and perturbations of the trajectory. For the platykurtic distributions of the perturbations, the L p -approximation with 3  <  p  <  4 was found to yield several <span class="hlt">times</span> more precise gravity estimates compared to the standard least-squares. The simulation results were confirmed by processing real gravity observations performed at the excessive noise conditions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4781461','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4781461"><span id="translatedtitle">Rapid detection of health-care-associated bloodstream infection in critical care using multipathogen real-<span class="hlt">time</span> polymerase chain reaction technology: a diagnostic <span class="hlt">accuracy</span> study and systematic review.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Warhurst, Geoffrey; Dunn, Graham; Chadwick, Paul; Blackwood, Bronagh; McAuley, Daniel; Perkins, Gavin D; McMullan, Ronan; Gates, Simon; Bentley, Andrew; Young, Duncan; Carlson, Gordon L; Dark, Paul</p> <p>2015-01-01</p> <p>BACKGROUND There is growing interest in the potential utility of real-<span class="hlt">time</span> polymerase chain reaction (PCR) in diagnosing bloodstream infection by detecting pathogen deoxyribonucleic acid (DNA) in blood samples within a few hours. SeptiFast (Roche Diagnostics GmBH, Mannheim, Germany) is a multipathogen probe-based system targeting ribosomal DNA sequences of bacteria and fungi. It detects and identifies the commonest pathogens causing bloodstream infection. As background to this study, we report a systematic review of Phase III diagnostic <span class="hlt">accuracy</span> studies of SeptiFast, which reveals uncertainty about its likely clinical utility based on widespread evidence of deficiencies in study design and reporting with a high risk of bias. OBJECTIVE Determine the <span class="hlt">accuracy</span> of SeptiFast real-<span class="hlt">time</span> PCR for the detection of health-care-associated bloodstream infection, against standard microbiological culture. DESIGN Prospective multicentre Phase III clinical diagnostic <span class="hlt">accuracy</span> study using the standards for the reporting of diagnostic <span class="hlt">accuracy</span> studies criteria. SETTING Critical care departments within NHS hospitals in the north-west of England. PARTICIPANTS Adult patients requiring blood culture (BC) when developing new signs of systemic inflammation. MAIN OUTCOME MEASURES SeptiFast real-<span class="hlt">time</span> PCR results at species/genus level compared with microbiological culture in association with independent adjudication of infection. Metrics of diagnostic <span class="hlt">accuracy</span> were derived including sensitivity, specificity, likelihood ratios and predictive values, with their 95% confidence intervals (CIs). Latent class analysis was used to explore the diagnostic performance of culture as a reference standard. RESULTS Of 1006 new patient episodes of systemic inflammation in 853 patients, 922 (92%) met the inclusion criteria and provided sufficient information for analysis. Index test assay failure occurred on 69 (7%) occasions. Adult patients had been exposed to a median of 8 days (interquartile range 4</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2004SPIE.5373..331D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2004SPIE.5373..331D"><span id="translatedtitle">Assessment of visual quality and spatial <span class="hlt">accuracy</span> of fast anisotropic diffusion and scan conversion algorithms for real-<span class="hlt">time</span> three-dimensional spherical ultrasound</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Duan, Qi; Angelini, Elsa D.; Laine, Andrew</p> <p>2004-04-01</p> <p>Three-dimensional ultrasound machines based on matrix phased-array transducers are gaining predominance for real-<span class="hlt">time</span> dynamic screening in cardiac and obstetric practice. These transducers array acquire three-dimensional data in spherical coordinates along lines tiled in azimuth and elevation angles at incremental depth. This study aims at evaluating fast filtering and scan conversion algorithms applied in the spherical domain prior to visualization into Cartesian coordinates for visual quality and spatial measurement <span class="hlt">accuracy</span>. Fast 3d scan conversion algorithms were implemented and with different order interpolation kernels. Downsizing and smoothing of sampling artifacts were integrated in the scan conversion process. In addition, a denoising scheme for spherical coordinate data with 3d anisotropic diffusion was implemented and applied prior to scan conversion to improve image quality. Reconstruction results under different parameter settings, such as different interpolation kernels, scaling factor, smoothing options, and denoising, are reported. Image quality was evaluated on several data sets via visual inspections and measurements of cylinder objects dimensions. Error measurements of the cylinder's radius, reported in this paper, show that the proposed fast scan conversion algorithm can correctly reconstruct three-dimensional ultrasound in Cartesian coordinates under tuned parameter settings. Denoising via three-dimensional anisotropic diffusion was able to greatly improve the quality of resampled data without affecting the <span class="hlt">accuracy</span> of spatial information after the modification of the introduction of a variable gradient threshold parameter.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/7023362','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/7023362"><span id="translatedtitle"><span class="hlt">Absolute</span> flux scale for radioastronomy</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Ivanov, V.P.; Stankevich, K.S.</p> <p>1986-07-01</p> <p>The authors propose and provide support for a new <span class="hlt">absolute</span> flux scale for radio astronomy, which is not encumbered with the inadequacies of the previous scales. In constructing it the method of relative spectra was used (a powerful tool for choosing reference spectra). A review is given of previous flux scales. The authors compare the AIS scale with the scale they propose. Both scales are based on <span class="hlt">absolute</span> measurements by the ''artificial moon'' method, and they are practically coincident in the range from 0.96 to 6 GHz. At frequencies above 6 GHz, 0.96 GHz, the AIS scale is overestimated because of incorrect extrapolation of the spectra of the primary and secondary standards. The major results which have emerged from this review of <span class="hlt">absolute</span> scales in radio astronomy are summarized.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.H24F..01S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.H24F..01S"><span id="translatedtitle"><span class="hlt">Absolute</span> Humidity and the Seasonality of Influenza (Invited)</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shaman, J. L.; Pitzer, V.; Viboud, C.; Grenfell, B.; Goldstein, E.; Lipsitch, M.</p> <p>2010-12-01</p> <p>Much of the observed wintertime increase of mortality in temperate regions is attributed to seasonal influenza. A recent re-analysis of laboratory experiments indicates that <span class="hlt">absolute</span> humidity strongly modulates the airborne survival and transmission of the influenza virus. Here we show that the onset of increased wintertime influenza-related mortality in the United States is associated with anomalously low <span class="hlt">absolute</span> humidity levels during the prior weeks. We then use an epidemiological model, in which observed <span class="hlt">absolute</span> humidity conditions temper influenza transmission rates, to successfully simulate the seasonal cycle of observed influenza-related mortality. The model results indicate that direct modulation of influenza transmissibility by <span class="hlt">absolute</span> humidity alone is sufficient to produce this observed seasonality. These findings provide epidemiological support for the hypothesis that <span class="hlt">absolute</span> humidity drives seasonal variations of influenza transmission in temperate regions. In addition, we show that variations of the basic and effective reproductive numbers for influenza, caused by seasonal changes in <span class="hlt">absolute</span> humidity, are consistent with the general <span class="hlt">timing</span> of pandemic influenza outbreaks observed for 2009 A/H1N1 in temperate regions. Indeed, <span class="hlt">absolute</span> humidity conditions correctly identify the region of the United States vulnerable to a third, wintertime wave of pandemic influenza. These findings suggest that the <span class="hlt">timing</span> of pandemic influenza outbreaks is controlled by a combination of <span class="hlt">absolute</span> humidity conditions, levels of susceptibility and changes in population mixing and contact rates.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_15");'>15</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li class="active"><span>17</span></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_17 --> <div id="page_18" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="341"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20070032798&hterms=radiometric+calibration&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dradiometric%2Bcalibration','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20070032798&hterms=radiometric+calibration&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D20%26Ntt%3Dradiometric%2Bcalibration"><span id="translatedtitle"><span class="hlt">Absolute</span> Radiometric Calibration of EUNIS-06</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thomas, R. J.; Rabin, D. M.; Kent, B. J.; Paustian, W.</p> <p>2007-01-01</p> <p>The Extreme-Ultraviolet Normal-Incidence Spectrometer (EUNIS) is a soundingrocket payload that obtains imaged high-resolution spectra of individual solar features, providing information about the Sun's corona and upper transition region. Shortly after its successful initial flight last year, a complete end-to-end calibration was carried out to determine the instrument's <span class="hlt">absolute</span> radiometric response over its Longwave bandpass of 300 - 370A. The measurements were done at the Rutherford-Appleton Laboratory (RAL) in England, using the same vacuum facility and EUV radiation source used in the pre-flight calibrations of both SOHO/CDS and Hinode/EIS, as well as in three post-flight calibrations of our SERTS sounding rocket payload, the precursor to EUNIS. The unique radiation source provided by the Physikalisch-Technische Bundesanstalt (PTB) had been calibrated to an <span class="hlt">absolute</span> <span class="hlt">accuracy</span> of 7% (l-sigma) at 12 wavelengths covering our bandpass directly against the Berlin electron storage ring BESSY, which is itself a primary radiometric source standard. Scans of the EUNIS aperture were made to determine the instrument's <span class="hlt">absolute</span> spectral sensitivity to +- 25%, considering all sources of error, and demonstrate that EUNIS-06 was the most sensitive solar E W spectrometer yet flown. The results will be matched against prior calibrations which relied on combining measurements of individual optical components, and on comparisons with theoretically predicted 'insensitive' line ratios. Coordinated observations were made during the EUNIS-06 flight by SOHO/CDS and EIT that will allow re-calibrations of those instruments as well. In addition, future EUNIS flights will provide similar calibration updates for TRACE, Hinode/EIS, and STEREO/SECCHI/EUVI.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20000000444','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20000000444"><span id="translatedtitle">Micron Accurate <span class="hlt">Absolute</span> Ranging System: Range Extension</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Smalley, Larry L.; Smith, Kely L.</p> <p>1999-01-01</p> <p>The purpose of this research is to investigate Fresnel diffraction as a means of obtaining <span class="hlt">absolute</span> distance measurements with micron or greater <span class="hlt">accuracy</span>. It is believed that such a system would prove useful to the Next Generation Space Telescope (NGST) as a non-intrusive, non-contact measuring system for use with secondary concentrator station-keeping systems. The present research attempts to validate past experiments and develop ways to apply the phenomena of Fresnel diffraction to micron accurate measurement. This report discusses past research on the phenomena, and the basis of the use Fresnel diffraction distance metrology. The apparatus used in the recent investigations, experimental procedures used, preliminary results are discussed in detail. Continued research and equipment requirements on the extension of the effective range of the Fresnel diffraction systems is also described.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFMGP51B..07L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFMGP51B..07L"><span id="translatedtitle">Swarm's <span class="hlt">Absolute</span> Scalar Magnetometer metrological performances</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leger, J.; Fratter, I.; Bertrand, F.; Jager, T.; Morales, S.</p> <p>2012-12-01</p> <p>The <span class="hlt">Absolute</span> Scalar Magnetometer (ASM) has been developed for the ESA Earth Observation Swarm mission, planned for launch in November 2012. As its Overhauser magnetometers forerunners flown on Oersted and Champ satellites, it will deliver high resolution scalar measurements for the in-flight calibration of the Vector Field Magnetometer manufactured by the Danish Technical University. Latest results of the ground tests carried out to fully characterize all parameters that may affect its <span class="hlt">accuracy</span>, both at instrument and satellite level, will be presented. In addition to its baseline function, the ASM can be operated either at a much higher sampling rate (burst mode at 250 Hz) or in a dual mode where it also delivers vector field measurements as a by-product. The calibration procedure and the relevant vector performances will be discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19820002595','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19820002595"><span id="translatedtitle">MAGSAT: Vector magnetometer <span class="hlt">absolute</span> sensor alignment determination</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Acuna, M. H.</p> <p>1981-01-01</p> <p>A procedure is described for accurately determining the <span class="hlt">absolute</span> alignment of the magnetic axes of a triaxial magnetometer sensor with respect to an external, fixed, reference coordinate system. The method does not require that the magnetic field vector orientation, as generated by a triaxial calibration coil system, be known to better than a few degrees from its true position, and minimizes the number of positions through which a sensor assembly must be rotated to obtain a solution. Computer simulations show that <span class="hlt">accuracies</span> of better than 0.4 seconds of arc can be achieved under typical test conditions associated with existing magnetic test facilities. The basic approach is similar in nature to that presented by McPherron and Snare (1978) except that only three sensor positions are required and the system of equations to be solved is considerably simplified. Applications of the method to the case of the MAGSAT Vector Magnetometer are presented and the problems encountered discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9639E..06L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9639E..06L"><span id="translatedtitle">Sentinel-2/MSI <span class="hlt">absolute</span> calibration: first results</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Lonjou, V.; Lachérade, S.; Fougnie, B.; Gamet, P.; Marcq, S.; Raynaud, J.-L.; Tremas, T.</p> <p>2015-10-01</p> <p>Sentinel-2 is an optical imaging mission devoted to the operational monitoring of land and coastal areas. It is developed in partnership between the European Commission and the European Space Agency. The Sentinel-2 mission is based on a satellites constellation deployed in polar sun-synchronous orbit. It will offer a unique combination of global coverage with a wide field of view (290km), a high revisit (5 days with two satellites), a high resolution (10m, 20m and 60m) and multi-spectral imagery (13 spectral bands in visible and shortwave infra-red domains). CNES is involved in the instrument commissioning in collaboration with ESA. This paper reviews all the techniques that will be used to insure an <span class="hlt">absolute</span> calibration of the 13 spectral bands better than 5% (target 3%), and will present the first results if available. First, the nominal calibration technique, based on an on-board sun diffuser, is detailed. Then, we show how vicarious calibration methods based on acquisitions over natural targets (oceans, deserts, and Antarctica during winter) will be used to check and improve the <span class="hlt">accuracy</span> of the <span class="hlt">absolute</span> calibration coefficients. Finally, the verification scheme, exploiting photometer in-situ measurements over Lacrau plain, is described. A synthesis, including spectral coherence, inter-methods agreement and temporal evolution, will conclude the paper.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014SPIE.9206E..0ER','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014SPIE.9206E..0ER"><span id="translatedtitle">Experimental results for <span class="hlt">absolute</span> cylindrical wavefront testing</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Reardon, Patrick J.; Alatawi, Ayshah</p> <p>2014-09-01</p> <p>Applications for Cylindrical and near-cylindrical surfaces are ever-increasing. However, fabrication of high quality cylindrical surfaces is limited by the difficulty of accurate and affordable metrology. <span class="hlt">Absolute</span> testing of such surfaces represents a challenge to the optical testing community as cylindrical reference wavefronts are difficult to produce. In this paper, preliminary results for a new method of <span class="hlt">absolute</span> testing of cylindrical wavefronts are presented. The method is based on the merging of the random ball test method with the fiber optic reference test. The random ball test assumes a large number of interferograms of a good quality sphere with errors that are statistically distributed such that the average of the errors goes to zero. The fiber optic reference test utilizes a specially processed optical fiber to provide a clean high quality reference wave from an incident line focus from the cylindrical wave under test. By taking measurements at different rotation and translations of the fiber, an analogous procedure can be employed to determine the quality of the converging cylindrical wavefront with high <span class="hlt">accuracy</span>. This paper presents and discusses the results of recent tests of this method using a null optic formed by a COTS cylindrical lens and a free-form polished corrector element.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1996AAS...188.0803D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1996AAS...188.0803D"><span id="translatedtitle"><span class="hlt">Absolute</span> Proper Motions of Southern Globular Clusters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Dinescu, D. I.; Girard, T. M.; van Altena, W. F.</p> <p>1996-05-01</p> <p>Our program involves the determination of <span class="hlt">absolute</span> proper motions with respect to galaxies for a sample of globular clusters situated in the southern sky. The plates cover a 6(deg) x 6(deg) area and are taken with the 51-cm double astrograph at Cesco Observatory in El Leoncito, Argentina. We have developed special methods to deal with the modelling error of the plate transformation and we correct for magnitude equation using the cluster stars. This careful astrometric treatment leads to <span class="hlt">accuracies</span> of from 0.5 to 1.0 mas/yr for the <span class="hlt">absolute</span> proper motion of each cluster, depending primarily on the number of measurable cluster stars which in turn is related to the cluster's distance. Space velocities are then derived which, in association with metallicities, provide key information for the formation scenario of the Galaxy, i.e. accretion and/or dissipational collapse. Here we present results for NGC 1851, NGC 6752, NGC 6584, NGC 6362 and NGC 288.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17022461','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17022461"><span id="translatedtitle">[<span class="hlt">Accuracy</span> of a real-<span class="hlt">time</span> polymerase-chain-reaction assay for a quantitative estimation of genetically modified sources in food products].</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Abramov, D D; Trofimov, D Iu; Rebrikov, D V</p> <p>2006-01-01</p> <p>The <span class="hlt">accuracy</span> of a real-<span class="hlt">time</span> polymerase-chain-reaction assay for genetically modified sources in food products was determined using two official test systems (kits) of primers and samples. These kits were recommended by the Federal Center of State Sanitary and Epidemiological Surveillance (Russian Ministry of Health) and the European Commission. We used the following three models of thermocyclers: iCycler iQ (BioRad, United States), Rotor-Gene 3000 (Corbett Research, Australia), and DT-322 (DNA-Technology, Russia). Studies of samples that contained 1% genetically modified sources showed that the error of a quantitative assay for genetically modified sources in food products corresponds to 20-30% and does not depend on the kit type and the thermocycler model used.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016CG.....90..144Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016CG.....90..144Y"><span id="translatedtitle">A method to improve the stability and <span class="hlt">accuracy</span> of ANN- and SVM-based <span class="hlt">time</span> series models for long-term groundwater level predictions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yoon, Heesung; Hyun, Yunjung; Ha, Kyoochul; Lee, Kang-Kun; Kim, Gyoo-Bum</p> <p>2016-05-01</p> <p>The prediction of long-term groundwater level fluctuations is necessary to effectively manage groundwater resources and to assess the effects of changes in rainfall patterns on groundwater resources. In the present study, a weighted error function approach was utilised to improve the performance of artificial neural network (ANN)- and support vector machine (SVM)-based recursive prediction models for the long-term prediction of groundwater levels in response to rainfall. The developed <span class="hlt">time</span> series models were applied to groundwater level data from 5 groundwater-monitoring stations in South Korea. The results demonstrated that the weighted error function approach can improve the stability and <span class="hlt">accuracy</span> of recursive prediction models, especially for ANN models. The comparison of the model performance showed that the recursive prediction performance of the SVM was superior to the performance of the ANN in this case study.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014PhyA..407...15O','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014PhyA..407...15O"><span id="translatedtitle">An <span class="hlt">absolute</span> measure for a key currency</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Oya, Shunsuke; Aihara, Kazuyuki; Hirata, Yoshito</p> <p></p> <p>It is generally considered that the US dollar and the euro are the key currencies in the world and in Europe, respectively. However, there is no <span class="hlt">absolute</span> general measure for a key currency. Here, we investigate the 24-hour periodicity of foreign exchange markets using a recurrence plot, and define an <span class="hlt">absolute</span> measure for a key currency based on the strength of the periodicity. Moreover, we analyze the <span class="hlt">time</span> evolution of this measure. The results show that the credibility of the US dollar has not decreased significantly since the Lehman shock, when the Lehman Brothers bankrupted and influenced the economic markets, and has increased even relatively better than that of the euro and that of the Japanese yen.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Absolutism&pg=3&id=EJ265369','ERIC'); return false;" href="http://eric.ed.gov/?q=Absolutism&pg=3&id=EJ265369"><span id="translatedtitle">Relativistic <span class="hlt">Absolutism</span> in Moral Education.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Vogt, W. Paul</p> <p>1982-01-01</p> <p>Discusses Emile Durkheim's "Moral Education: A Study in the Theory and Application of the Sociology of Education," which holds that morally healthy societies may vary in culture and organization but must possess <span class="hlt">absolute</span> rules of moral behavior. Compares this moral theory with current theory and practice of American educators. (MJL)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/15010495','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/15010495"><span id="translatedtitle">High Mass Measurement <span class="hlt">Accuracy</span> Determination for Proteomics using Multivariate Regression Fitting: Application to Electrospray Ionization <span class="hlt">Time</span>-Of-Flight Mass Spectrometry</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Strittmatter, Eric F.; Rodriguez, Nestor; Smith, Richard D.</p> <p>2003-02-01</p> <p>Important factors that limit the mass measurement <span class="hlt">accuracy</span> from a mass spectrometer are related to (1) the type of mass analyzer used and (2) the data processing/calibration methods used to obtain mass values from the raw data. Here, two data processing methods are presented that correct for systematic deviations when measuring the mass of ions using a <span class="hlt">time</span>-of-flight (TOF) mass spectrometer. The first fitting method is one where m/z values are obtained from fitting peak distributions using double Gaussian functions. A second calibration method takes into account the slight non-linear response of the <span class="hlt">time</span>-of-flight analyzer in addition to the drift in the calibration over <span class="hlt">time</span>. Using multivariate regression, both of these two effects can be corrected for using a single calibration formula. Achievable performance was evaluated with a trypsin digestion of serum albumin and proteins from the organism D. radiodurans that were analyzed using gradient reverse-phase liquid chromatography combined with electrospray ionization orthogonal TOF mass spectrometer. The root mean square deviation between the theoretical and experimental m/z for serum albumin was found to be 8 ppm using the double Gaussian-multivariate method compared to 29 ppm determined using linear calibration and normal peak centroiding. An advantage of the methods presented here is that no calibrant compounds need to be added to the mobile phase, thereby avoiding interference effects and signal suppression of analytes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22878565','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22878565"><span id="translatedtitle">Computerized assessment of pedophilic sexual interest through self-report and viewing <span class="hlt">time</span>: reliability, validity, and classification <span class="hlt">accuracy</span> of the affinity program.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Mokros, Andreas; Gebhard, Michael; Heinz, Volker; Marschall, Roland W; Nitschke, Joachim; Glasgow, David V; Gress, Carmen L Z; Laws, D Richard</p> <p>2013-06-01</p> <p>Affinity is a computerized assessment tool that combines viewing <span class="hlt">time</span> and self-report measures of sexual interest. The present study was designed to assess the diagnostic properties of Affinity with respect to sexual interest in prepubescent children. Reliability of both self-report and viewing <span class="hlt">time</span> components was estimated to be high. The group profile of a sample of pedophilic adult male child molesters (n = 42, all of whom admitted their offenses) differed from the group profiles of male community controls (n = 95) and male nonsexual offenders (n = 27), respectively. More specifically, both ratings and viewing <span class="hlt">times</span> for images showing small children or prejuvenile children were significantly higher within the child molester sample than in either of the other two groups, attesting to the validity of the measures. Overall classification <span class="hlt">accuracy</span>, however, was mediocre: A multivariate classification routine yielded 50% sensitivity for child molester status at the cost of 13% false positives. The implications for forensic use of Affinity are discussed. PMID:22878565</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19820012627','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19820012627"><span id="translatedtitle">High <span class="hlt">accuracy</span> OMEGA timekeeping</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Imbier, E. A.</p> <p>1982-01-01</p> <p>The Smithsonian Astrophysical Observatory (SAO) operates a worldwide satellite tracking network which uses a combination of OMEGA as a frequency reference, dual <span class="hlt">timing</span> channels, and portable clock comparisons to maintain accurate epoch <span class="hlt">time</span>. Propagational charts from the U.S. Coast Guard OMEGA monitor program minimize diurnal and seasonal effects. Daily phase value publications of the U.S. Naval Observatory provide corrections to the field collected <span class="hlt">timing</span> data to produce an averaged <span class="hlt">time</span> line comprised of straight line segments called a <span class="hlt">time</span> history file (station clock minus UTC). Depending upon clock location, reduced <span class="hlt">time</span> data <span class="hlt">accuracies</span> of between two and eight microseconds are typical.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21385585','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21385585"><span id="translatedtitle">Measurement of <span class="hlt">absolute</span> T cell receptor rearrangement diversity.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Baum, Paul D; Young, Jennifer J; McCune, Joseph M</p> <p>2011-05-31</p> <p>T cell receptor (TCR) diversity is critical for adaptive immunity. Existing methods for measuring such diversity are qualitative, expensive, and/or of uncertain <span class="hlt">accuracy</span>. Here, we describe a method and associated reagents for estimating the <span class="hlt">absolute</span> number of unique TCR Vβ rearrangements present in a given number of cells or volume of blood. Compared to next generation sequencing, this method is rapid, reproducible, and affordable. Diversity of a sample is calculated based on three independent measurements of one Vβ-Jβ family of TCR rearrangements at a <span class="hlt">time</span>. The percentage of receptors using the given Vβ gene is determined by flow cytometric analysis of T cells stained with anti-Vβ family antibodies. The percentage of receptors using the Vβ gene in combination with the chosen Jβ gene is determined by quantitative PCR. Finally, the <span class="hlt">absolute</span> clonal diversity of the Vβ-Jβ family is determined with the AmpliCot method of DNA hybridization kinetics, by interpolation relative to PCR standards of known sequence diversity. These three component measurements are reproducible and linear. Using titrations of known numbers of input cells, we show that the TCR diversity estimates obtained by this approach approximate expected values within a two-fold error, have a coefficient of variation of 20%, and yield similar results when different Vβ-Jβ pairs are chosen. The ability to obtain accurate measurements of the total number of different TCR gene rearrangements in a cell sample should be useful for basic studies of the adaptive immune system as well as in clinical studies of conditions such as HIV disease, transplantation, aging, and congenital immunodeficiencies. PMID:21385585</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3191580','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3191580"><span id="translatedtitle">The clinical diagnostic <span class="hlt">accuracy</span> of rapid detection of healthcare-associated bloodstream infection in intensive care using multipathogen real-<span class="hlt">time</span> PCR technology</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Dunn, Graham; Chadwick, Paul; Young, Duncan; Bentley, Andrew; Carlson, Gordon; Warhurst, Geoffrey</p> <p>2011-01-01</p> <p>Background There is growing interest in the potential utility of real-<span class="hlt">time</span> PCR in diagnosing bloodstream infection by detecting pathogen DNA in blood samples within a few hours. SeptiFast is a multipathogen probe-based real-<span class="hlt">time</span> PCR system targeting ribosomal DNA sequences of bacteria and fungi. It detects and identifies the commonest pathogens causing bloodstream infection and has European regulatory approval. The SeptiFast pathogen panel is suited to identifying healthcare-associated bloodstream infection acquired during complex healthcare, and the authors report here the protocol for the first detailed health-technology assessment of multiplex real-<span class="hlt">time</span> PCR in this setting. Methods/design A Phase III multicentre double-blinded diagnostic study will determine the clinical validity of SeptiFast for the rapid detection of healthcare-associated bloodstream infection, against the current service standard of microbiological culture, in an adequately sized population of critically ill adult patients. Results from SeptiFast and standard microbiological culture procedures in each patient will be compared at study conclusion and the metrics of clinical diagnostic <span class="hlt">accuracy</span> of SeptiFast determined in this population setting. In addition, this study aims to assess further the preliminary evidence that the detection of pathogen DNA in the bloodstream using SeptiFast may have value in identifying the presence of infection elsewhere in the body. Furthermore, differences in circulating immune-inflammatory markers in patient groups differentiated by the presence/absence of culturable pathogens and pathogen DNA will help elucidate further the patho-physiology of infection developing in the critically ill. Ethics and dissemination Ethical approval has been granted by the North West 6 Research Ethics Committee (09/H1003/109). Based on the results of this first non-commercial study, independent recommendations will be made to The Department of Health (open-access health technology</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2007AGUFM.V41E..01S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2007AGUFM.V41E..01S"><span id="translatedtitle">A Methodology for <span class="hlt">Absolute</span> Isotope Composition Measurement</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shen, J. J.; Lee, D.; Liang, W.</p> <p>2007-12-01</p> <p>Double spike technique was a well defined method for isotope composition measurement by TIMS of samples which have natural mass fractionation effect, but it is still a problem to define the isotope composition for double spike itself. In this study, we modified the old double spike technique and found that we could use the modified technique to solve the ¡§true¡¨ isotope composition of double spike itself. According the true isotope composition of double spike, we can measure the <span class="hlt">absolute</span> isotope composition if the sample has natural fractionation effect. A new vector analytical method has been developed in order to obtain the true isotopic composition of a 42Ca-48Ca double spike, and this is achieved by using two different sample-spike mixtures combined with the double spike and the natural Ca data. Because the natural sample, the two mixtures, and the spike should all lie on a single mixing line, we are able to constrain the true isotopic composition of our double spike using this new approach. This method not only can be used in Ca system but also in Ti, Cr, Fe, Ni, Zn, Mo, Ba and Pb systems. The <span class="hlt">absolute</span> double spike isotopic ratio is important, which can save a lot of <span class="hlt">time</span> to check different reference standards. Especially for Pb, radiogenic isotope system, the decay systems embodied in three of four naturally occurring isotopes induce difficult to obtain true isotopic ratios for <span class="hlt">absolute</span> dating.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24109783','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24109783"><span id="translatedtitle">DT-MRI measurement of myolaminar structure: <span class="hlt">accuracy</span> and sensitivity to <span class="hlt">time</span> post-fixation, b-value and number of directions.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gilbert, Stephen H; Smaill, Bruce H; Walton, Richard D; Trew, Mark L; Bernus, Olivier</p> <p>2013-01-01</p> <p>DT-MRI has been widely used to quantify myocardial fiber and laminar orientations. These structural orientations influence both the spread of excitation and the reorganization of the myocardium during contraction and are altered in disease states. Studies have sought to validate DT-MRI but questions remain about the <span class="hlt">accuracy</span> of the method and its sensitivity to the <span class="hlt">time</span> post-fixation and imaging parameters, including b-value, number of diffusion directions and image voxel size. The advent of high-spatial resolution ex vivo MRI and structure tensor (ST) analysis provides a means of direct validation of DT-MRI and assessment of sensitivity to the b-value, the number of diffusion directions and the image voxel size. We find that, with the fixation method we used, structure does not change with <span class="hlt">time</span> (up to 72 hours). We show that DT-MRI and ST/HR-MRI are markedly similar measures of fiber orientation but DT-MRI and ST are much less similar measures of laminar orientation. DT-MRI performance is not sensitive to the number of directions, with similar structural orientations measured with 6 or 12 directions. Likewise, DT-MRI performance is generally insensitive to b-value, but laminar measurement is moderately more accurate at b = 500 than for higher b-values.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26280315','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26280315"><span id="translatedtitle">Relative errors can cue <span class="hlt">absolute</span> visuomotor mappings.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>van Dam, Loes C J; Ernst, Marc O</p> <p>2015-12-01</p> <p>When repeatedly switching between two visuomotor mappings, e.g. in a reaching or pointing task, adaptation tends to speed up over <span class="hlt">time</span>. That is, when the error in the feedback corresponds to a mapping switch, fast adaptation occurs. Yet, what is learned, the relative error or the <span class="hlt">absolute</span> mappings? When switching between mappings, errors with a size corresponding to the relative difference between the mappings will occur more often than other large errors. Thus, we could learn to correct more for errors with this familiar size (Error Learning). On the other hand, it has been shown that the human visuomotor system can store several <span class="hlt">absolute</span> visuomotor mappings (Mapping Learning) and can use associated contextual cues to retrieve them. Thus, when contextual information is present, no error feedback is needed to switch between mappings. Using a rapid pointing task, we investigated how these two types of learning may each contribute when repeatedly switching between mappings in the absence of task-irrelevant contextual cues. After training, we examined how participants changed their behaviour when a single error probe indicated either the often-experienced error (Error Learning) or one of the previously experienced <span class="hlt">absolute</span> mappings (Mapping Learning). Results were consistent with Mapping Learning despite the relative nature of the error information in the feedback. This shows that errors in the feedback can have a double role in visuomotor behaviour: they drive the general adaptation process by making corrections possible on subsequent movements, as well as serve as contextual cues that can signal a learned <span class="hlt">absolute</span> mapping. PMID:26280315</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016PhRvA..94a3808D&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016PhRvA..94a3808D&link_type=ABSTRACT"><span id="translatedtitle">Optomechanics for <span class="hlt">absolute</span> rotation detection</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Davuluri, Sankar</p> <p>2016-07-01</p> <p>In this article, we present an application of optomechanical cavity for the <span class="hlt">absolute</span> rotation detection. The optomechanical cavity is arranged in a Michelson interferometer in such a way that the classical centrifugal force due to rotation changes the length of the optomechanical cavity. The change in the cavity length induces a shift in the frequency of the cavity mode. The phase shift corresponding to the frequency shift in the cavity mode is measured at the interferometer output to estimate the angular velocity of <span class="hlt">absolute</span> rotation. We derived an analytic expression to estimate the minimum detectable rotation rate in our scheme for a given optomechanical cavity. Temperature dependence of the rotation detection sensitivity is studied.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_16");'>16</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li class="active"><span>18</span></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_18 --> <div id="page_19" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="361"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11262641','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11262641"><span id="translatedtitle">Moral <span class="hlt">absolutism</span> and ectopic pregnancy.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kaczor, C</p> <p>2001-02-01</p> <p>If one accepts a version of <span class="hlt">absolutism</span> that excludes the intentional killing of any innocent human person from conception to natural death, ectopic pregnancy poses vexing difficulties. Given that the embryonic life almost certainly will die anyway, how can one retain one's moral principle and yet adequately respond to a situation that gravely threatens the life of the mother and her future fertility? The four options of treatment most often discussed in the literature are non-intervention, salpingectomy (removal of tube with embryo), salpingostomy (removal of embryo alone), and use of methotrexate (MXT). In this essay, I review these four options and introduce a fifth (the milking technique). In order to assess these options in terms of the <span class="hlt">absolutism</span> mentioned, it will also be necessary to discuss various accounts of the intention/foresight distinction. I conclude that salpingectomy, salpingostomy, and the milking technique are compatible with absolutist presuppositions, but not the use of methotrexate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/11262641','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/11262641"><span id="translatedtitle">Moral <span class="hlt">absolutism</span> and ectopic pregnancy.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kaczor, C</p> <p>2001-02-01</p> <p>If one accepts a version of <span class="hlt">absolutism</span> that excludes the intentional killing of any innocent human person from conception to natural death, ectopic pregnancy poses vexing difficulties. Given that the embryonic life almost certainly will die anyway, how can one retain one's moral principle and yet adequately respond to a situation that gravely threatens the life of the mother and her future fertility? The four options of treatment most often discussed in the literature are non-intervention, salpingectomy (removal of tube with embryo), salpingostomy (removal of embryo alone), and use of methotrexate (MXT). In this essay, I review these four options and introduce a fifth (the milking technique). In order to assess these options in terms of the <span class="hlt">absolutism</span> mentioned, it will also be necessary to discuss various accounts of the intention/foresight distinction. I conclude that salpingectomy, salpingostomy, and the milking technique are compatible with absolutist presuppositions, but not the use of methotrexate. PMID:11262641</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20100014902&hterms=asp&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dasp','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20100014902&hterms=asp&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3Dasp"><span id="translatedtitle">The <span class="hlt">Absolute</span> Spectrum Polarimeter (ASP)</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Kogut, A. J.</p> <p>2010-01-01</p> <p>The <span class="hlt">Absolute</span> Spectrum Polarimeter (ASP) is an Explorer-class mission to map the <span class="hlt">absolute</span> intensity and linear polarization of the cosmic microwave background and diffuse astrophysical foregrounds over the full sky from 30 GHz to 5 THz. The principal science goal is the detection and characterization of linear polarization from an inflationary epoch in the early universe, with tensor-to-scalar ratio r much greater than 1O(raised to the power of { -3}) and Compton distortion y < 10 (raised to the power of{-6}). We describe the ASP instrument and mission architecture needed to detect the signature of an inflationary epoch in the early universe using only 4 semiconductor bolometers.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15831074','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15831074"><span id="translatedtitle">Classification images predict <span class="hlt">absolute</span> efficiency.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Murray, Richard F; Bennett, Patrick J; Sekuler, Allison B</p> <p>2005-02-24</p> <p>How well do classification images characterize human observers' strategies in perceptual tasks? We show mathematically that from the classification image of a noisy linear observer, it is possible to recover the observer's <span class="hlt">absolute</span> efficiency. If we could similarly predict human observers' performance from their classification images, this would suggest that the linear model that underlies use of the classification image method is adequate over the small range of stimuli typically encountered in a classification image experiment, and that a classification image captures most important aspects of human observers' performance over this range. In a contrast discrimination task and in a shape discrimination task, we found that observers' <span class="hlt">absolute</span> efficiencies were generally well predicted by their classification images, although consistently slightly (approximately 13%) higher than predicted. We consider whether a number of plausible nonlinearities can account for the slight under prediction, and of these we find that only a form of phase uncertainty can account for the discrepancy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1175308','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1175308"><span id="translatedtitle"><span class="hlt">Absolute</span> calibration of optical flats</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Sommargren, Gary E.</p> <p>2005-04-05</p> <p>The invention uses the phase shifting diffraction interferometer (PSDI) to provide a true point-by-point measurement of <span class="hlt">absolute</span> flatness over the surface of optical flats. Beams exiting the fiber optics in a PSDI have perfect spherical wavefronts. The measurement beam is reflected from the optical flat and passed through an auxiliary optic to then be combined with the reference beam on a CCD. The combined beams include phase errors due to both the optic under test and the auxiliary optic. Standard phase extraction algorithms are used to calculate this combined phase error. The optical flat is then removed from the system and the measurement fiber is moved to recombine the two beams. The newly combined beams include only the phase errors due to the auxiliary optic. When the second phase measurement is subtracted from the first phase measurement, the <span class="hlt">absolute</span> phase error of the optical flat is obtained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/11921048','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/11921048"><span id="translatedtitle">Prognostic <span class="hlt">accuracy</span> of cerebral blood flow measurement by perfusion computed tomography, at the <span class="hlt">time</span> of emergency room admission, in acute stroke patients.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wintermark, Max; Reichhart, Marc; Thiran, Jean-Philippe; Maeder, Philippe; Chalaron, Marc; Schnyder, Pierre; Bogousslavsky, Julien; Meuli, Reto</p> <p>2002-04-01</p> <p>The purpose of this study was to determine the prognostic <span class="hlt">accuracy</span> of perfusion computed tomography (CT), performed at the <span class="hlt">time</span> of emergency room admission, in acute stroke patients. <span class="hlt">Accuracy</span> was determined by comparison of perfusion CT with delayed magnetic resonance (MR) and by monitoring the evolution of each patient's clinical condition. Twenty-two acute stroke patients underwent perfusion CT covering four contiguous 10mm slices on admission, as well as delayed MR, performed after a median interval of 3 days after emergency room admission. Eight were treated with thrombolytic agents. Infarct size on the admission perfusion CT was compared with that on the delayed diffusion-weighted (DWI)-MR, chosen as the gold standard. Delayed magnetic resonance angiography and perfusion-weighted MR were used to detect recanalization. A potential recuperation ratio, defined as PRR = penumbra size/(penumbra size + infarct size) on the admission perfusion CT, was compared with the evolution in each patient's clinical condition, defined by the National Institutes of Health Stroke Scale (NIHSS). In the 8 cases with arterial recanalization, the size of the cerebral infarct on the delayed DWI-MR was larger than or equal to that of the infarct on the admission perfusion CT, but smaller than or equal to that of the ischemic lesion on the admission perfusion CT; and the observed improvement in the NIHSS correlated with the PRR (correlation coefficient = 0.833). In the 14 cases with persistent arterial occlusion, infarct size on the delayed DWI-MR correlated with ischemic lesion size on the admission perfusion CT (r = 0.958). In all 22 patients, the admission NIHSS correlated with the size of the ischemic area on the admission perfusion CT (r = 0.627). Based on these findings, we conclude that perfusion CT allows the accurate prediction of the final infarct size and the evaluation of clinical prognosis for acute stroke patients at the <span class="hlt">time</span> of emergency evaluation. It may also provide</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ISPAr41B1..601H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ISPAr41B1..601H"><span id="translatedtitle"><span class="hlt">Accuracy</span> Assessment of Mobile Mapping Point Clouds Using the Existing Environment as Terrestrial Reference</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hofmann, S.; Brenner, C.</p> <p>2016-06-01</p> <p>Mobile mapping data is widely used in various applications, what makes it especially important for data users to get a statistically verified quality statement on the geometric <span class="hlt">accuracy</span> of the acquired point clouds or its processed products. The <span class="hlt">accuracy</span> of point clouds can be divided into an <span class="hlt">absolute</span> and a relative quality, where the <span class="hlt">absolute</span> quality describes the position of the point cloud in a world coordinate system such as WGS84 or UTM, whereas the relative <span class="hlt">accuracy</span> describes the <span class="hlt">accuracy</span> within the point cloud itself. Furthermore, the quality of processed products such as segmented features depends on the global <span class="hlt">accuracy</span> of the point cloud but mainly on the quality of the processing steps. Several data sources with different characteristics and quality can be thought of as potential reference data, such as cadastral maps, orthophoto, artificial control objects or terrestrial surveys using a total station. In this work a test field in a selected residential area was acquired as reference data in a terrestrial survey using a total station. In order to reach high <span class="hlt">accuracy</span> the stationing of the total station was based on a newly made geodetic network with a local <span class="hlt">accuracy</span> of less than 3 mm. The global position of the network was determined using a long <span class="hlt">time</span> GNSS survey reaching an <span class="hlt">accuracy</span> of 8 mm. Based on this geodetic network a 3D test field with facades and street profiles was measured with a total station, each point with a two-dimensional position and altitude. In addition, the surface of poles of street lights, traffic signs and trees was acquired using the scanning mode of the total station. Comparing this reference data to the acquired mobile mapping point clouds of several measurement campaigns a detailed quality statement on the <span class="hlt">accuracy</span> of the point cloud data is made. Additionally, the advantages and disadvantages of the described reference data source concerning availability, cost, <span class="hlt">accuracy</span> and applicability are discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21033851','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21033851"><span id="translatedtitle">Strategy for the <span class="hlt">absolute</span> neutron emission measurement on ITER.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Sasao, M; Bertalot, L; Ishikawa, M; Popovichev, S</p> <p>2010-10-01</p> <p><span class="hlt">Accuracy</span> of 10% is demanded to the <span class="hlt">absolute</span> fusion measurement on ITER. To achieve this <span class="hlt">accuracy</span>, a functional combination of several types of neutron measurement subsystem, cross calibration among them, and in situ calibration are needed. Neutron transport calculation shows the suitable calibration source is a DT/DD neutron generator of source strength higher than 10(10) n/s (neutron/second) for DT and 10(8) n/s for DD. It will take eight weeks at the minimum with this source to calibrate flux monitors, profile monitors, and the activation system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22058653','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22058653"><span id="translatedtitle">Strategy for the <span class="hlt">absolute</span> neutron emission measurement on ITER</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sasao, M.; Bertalot, L.; Ishikawa, M.; Popovichev, S.</p> <p>2010-10-15</p> <p><span class="hlt">Accuracy</span> of 10% is demanded to the <span class="hlt">absolute</span> fusion measurement on ITER. To achieve this <span class="hlt">accuracy</span>, a functional combination of several types of neutron measurement subsystem, cross calibration among them, and in situ calibration are needed. Neutron transport calculation shows the suitable calibration source is a DT/DD neutron generator of source strength higher than 10{sup 10} n/s (neutron/second) for DT and 10{sup 8} n/s for DD. It will take eight weeks at the minimum with this source to calibrate flux monitors, profile monitors, and the activation system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20150023302','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20150023302"><span id="translatedtitle">Error Budget for a Calibration Demonstration System for the Reflected Solar Instrument for the Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thome, Kurtis; McCorkel, Joel; McAndrew, Brendan</p> <p>2013-01-01</p> <p>A goal of the Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory (CLARREO) mission is to observe highaccuracy, long-term climate change trends over decadal <span class="hlt">time</span> scales. The key to such a goal is to improving the <span class="hlt">accuracy</span> of SI traceable <span class="hlt">absolute</span> calibration across infrared and reflected solar wavelengths allowing climate change to be separated from the limit of natural variability. The advances required to reach on-orbit <span class="hlt">absolute</span> <span class="hlt">accuracy</span> to allow climate change observations to survive data gaps exist at NIST in the laboratory, but still need demonstration that the advances can move successfully from to NASA and/or instrument vendor capabilities for spaceborne instruments. The current work describes the radiometric calibration error budget for the Solar, Lunar for <span class="hlt">Absolute</span> Reflectance Imaging Spectroradiometer (SOLARIS) which is the calibration demonstration system (CDS) for the reflected solar portion of CLARREO. The goal of the CDS is to allow the 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. The resulting SI-traceable error budget for reflectance retrieval using solar irradiance as a reference and methods for laboratory-based, <span class="hlt">absolute</span> calibration suitable for climatequality data collections is given. Key components in the error budget are geometry differences between the solar and earth views, knowledge of attenuator behavior when viewing the sun, and sensor behavior such as detector linearity and noise behavior. Methods for demonstrating this error budget are also presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016PhRvD..93k3020Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016PhRvD..93k3020Z"><span id="translatedtitle">Improved statistical determination of <span class="hlt">absolute</span> neutrino masses via radiative emission of neutrino pairs from atoms</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zhang, Jue; Zhou, Shun</p> <p>2016-06-01</p> <p>The atomic transition from an excited state |e ⟩ to the ground state |g ⟩ by emitting a neutrino pair and a photon, i.e., |e ⟩→|g ⟩+|γ ⟩+|νi⟩+|ν¯j⟩ with i , j =1 , 2, 3, has been proposed by Yoshimura and his collaborators as an alternative way to determine the <span class="hlt">absolute</span> scale m0 of neutrino masses. More recently, a statistical analysis of the fine structure of the photon spectrum from this atomic process has been performed [N. Song et al. Phys. Rev. D 93, 013020 (2016)] to quantitatively examine the experimental requirements for a realistic determination of <span class="hlt">absolute</span> neutrino masses. In this paper, we show how to improve the statistical analysis and demonstrate that the previously required detection <span class="hlt">time</span> can be reduced by one order of magnitude for the case of a 3 σ determination of m0˜0.01 eV with an <span class="hlt">accuracy</span> better than 10%. Such an improvement is very encouraging for further investigations on measuring <span class="hlt">absolute</span> neutrino masses through atomic processes.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21120798','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21120798"><span id="translatedtitle">Radio frequency controlled synthetic wavelength sweep for <span class="hlt">absolute</span> distance measurement by optical interferometry</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Le Floch, Sebastien; Salvade, Yves; Mitouassiwou, Rostand; Favre, Patrick</p> <p>2008-06-01</p> <p>We present a new technique applied to the variable optical synthetic wavelength generation in optical interferometry. It consists of a chain of optical injection locking among three lasers: first a distributed-feedback laser is used as a master to injection lock an intensity-modulated laser that is directly modulated around 15 GHz by a radio frequency generator on a sideband. A second distributed-feedback laser is injection locked on another sideband of the intensity-modulated laser. The variable synthetic wavelength for <span class="hlt">absolute</span> distance measurement is simply generated by sweeping the radio frequency over a range of several hundred megahertz, which corresponds to the locking range of the two slave lasers. In this condition, the uncertainty of the variable synthetic wavelength is equivalent to the radio frequency uncertainty. This latter has a relative <span class="hlt">accuracy</span> of 10{sup -7} or better, resulting in a resolution of {+-}25 {mu}m for distances exceeding tens of meters. The radio frequency generator produces a linear frequency sweep of 1 ms duration (i.e., exactly equal to one <span class="hlt">absolute</span> distance measurement acquisition <span class="hlt">time</span>), with frequency steps of about 1 MHz. Finally, results of <span class="hlt">absolute</span> distance measurements for ranges up to 10 m are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009acse.book..955S&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009acse.book..955S&link_type=ABSTRACT"><span id="translatedtitle"><span class="hlt">Absolute</span> Priority for a Vehicle in VANET</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Shirani, Rostam; Hendessi, Faramarz; Montazeri, Mohammad Ali; Sheikh Zefreh, Mohammad</p> <p></p> <p>In today's world, traffic jams waste hundreds of hours of our life. This causes many researchers try to resolve the problem with the idea of Intelligent Transportation System. For some applications like a travelling ambulance, it is important to reduce delay even for a second. In this paper, we propose a completely infrastructure-less approach for finding shortest path and controlling traffic light to provide <span class="hlt">absolute</span> priority for an emergency vehicle. We use the idea of vehicular ad-hoc networking to reduce the imposed travelling <span class="hlt">time</span>. Then, we simulate our proposed protocol and compare it with a centrally controlled traffic light system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1287535','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1287535"><span id="translatedtitle">Familial Aggregation of <span class="hlt">Absolute</span> Pitch</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Baharloo, Siamak; Service, Susan K.; Risch, Neil; Gitschier, Jane; Freimer, Nelson B.</p> <p>2000-01-01</p> <p><span class="hlt">Absolute</span> pitch (AP) is a behavioral trait that is defined as the ability to identify the pitch of tones in the absence of a reference pitch. AP is an ideal phenotype for investigation of gene and environment interactions in the development of complex human behaviors. Individuals who score exceptionally well on formalized auditory tests of pitch perception are designated as “AP-1.” As described in this report, auditory testing of siblings of AP-1 probands and of a control sample indicates that AP-1 aggregates in families. The implications of this finding for the mapping of loci for AP-1 predisposition are discussed. PMID:10924408</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016SPIE.9903E..1OF','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016SPIE.9903E..1OF"><span id="translatedtitle">Precision evaluation of calibration factor of a superconducting gravimeter using an <span class="hlt">absolute</span> gravimeter</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Feng, Jin-yang; Wu, Shu-qing; Li, Chun-jian; Su, Duo-wu; Xu, Jin-yi; Yu, Mei</p> <p>2016-01-01</p> <p>The precision of the calibration factor of a superconducting gravimeter (SG) using an <span class="hlt">absolute</span> gravimeter (AG) is analyzed based on linear least square fitting and error propagation theory and factors affecting the <span class="hlt">accuracy</span> are discussed. It can improve the <span class="hlt">accuracy</span> to choose the observation period of solid tide as a significant change or increase the calibration <span class="hlt">time</span>. Simulation is carried out based on synthetic gravity tides calculated with T-soft at observed site from Aug. 14th to Sept. 2nd in 2014. The result indicates that the highest precision using half a day's observation data is below 0.28% and the precision exponentially increases with the increase of peak-to-peak gravity change. The comparison of results obtained from the same observation <span class="hlt">time</span> indicated that using properly selected observation data has more beneficial on the improvement of precision. Finally, the calibration experiment of the SG iGrav-012 is introduced and the calibration factor is determined for the first <span class="hlt">time</span> using AG FG5X-249. With 2.5 days' data properly selected from solid tide period with large tidal amplitude, the determined calibration factor of iGrav-012 is (-92.54423+/-0.13616) μGal/V (1μGal=10-8m/s2), with the relative <span class="hlt">accuracy</span> of about 0.15%.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26627950','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26627950"><span id="translatedtitle">Linear-scaling <span class="hlt">time</span>-dependent density-functional theory beyond the Tamm-Dancoff approximation: Obtaining efficiency and <span class="hlt">accuracy</span> with in situ optimised local orbitals.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zuehlsdorff, T J; Hine, N D M; Payne, M C; Haynes, P D</p> <p>2015-11-28</p> <p>We present a solution of the full <span class="hlt">time</span>-dependent density-functional theory (TDDFT) eigenvalue equation in the linear response formalism exhibiting a linear-scaling computational complexity with system size, without relying on the simplifying Tamm-Dancoff approximation (TDA). The implementation relies on representing the occupied and unoccupied subspaces with two different sets of in situ optimised localised functions, yielding a very compact and efficient representation of the transition density matrix of the excitation with the <span class="hlt">accuracy</span> associated with a systematic basis set. The TDDFT eigenvalue equation is solved using a preconditioned conjugate gradient algorithm that is very memory-efficient. The algorithm is validated on a small test molecule and a good agreement with results obtained from standard quantum chemistry packages is found, with the preconditioner yielding a significant improvement in convergence rates. The method developed in this work is then used to reproduce experimental results of the absorption spectrum of bacteriochlorophyll in an organic solvent, where it is demonstrated that the TDA fails to reproduce the main features of the low energy spectrum, while the full TDDFT equation yields results in good qualitative agreement with experimental data. Furthermore, the need for explicitly including parts of the solvent into the TDDFT calculations is highlighted, making the treatment of large system sizes necessary that are well within reach of the capabilities of the algorithm introduced here. Finally, the linear-scaling properties of the algorithm are demonstrated by computing the lowest excitation energy of bacteriochlorophyll in solution. The largest systems considered in this work are of the same order of magnitude as a variety of widely studied pigment-protein complexes, opening up the possibility of studying their properties without having to resort to any semiclassical approximations to parts of the protein environment. PMID:26627950</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JChPh.143t4107Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JChPh.143t4107Z"><span id="translatedtitle">Linear-scaling <span class="hlt">time</span>-dependent density-functional theory beyond the Tamm-Dancoff approximation: Obtaining efficiency and <span class="hlt">accuracy</span> with in situ optimised local orbitals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zuehlsdorff, T. J.; Hine, N. D. M.; Payne, M. C.; Haynes, P. D.</p> <p>2015-11-01</p> <p>We present a solution of the full <span class="hlt">time</span>-dependent density-functional theory (TDDFT) eigenvalue equation in the linear response formalism exhibiting a linear-scaling computational complexity with system size, without relying on the simplifying Tamm-Dancoff approximation (TDA). The implementation relies on representing the occupied and unoccupied subspaces with two different sets of in situ optimised localised functions, yielding a very compact and efficient representation of the transition density matrix of the excitation with the <span class="hlt">accuracy</span> associated with a systematic basis set. The TDDFT eigenvalue equation is solved using a preconditioned conjugate gradient algorithm that is very memory-efficient. The algorithm is validated on a small test molecule and a good agreement with results obtained from standard quantum chemistry packages is found, with the preconditioner yielding a significant improvement in convergence rates. The method developed in this work is then used to reproduce experimental results of the absorption spectrum of bacteriochlorophyll in an organic solvent, where it is demonstrated that the TDA fails to reproduce the main features of the low energy spectrum, while the full TDDFT equation yields results in good qualitative agreement with experimental data. Furthermore, the need for explicitly including parts of the solvent into the TDDFT calculations is highlighted, making the treatment of large system sizes necessary that are well within reach of the capabilities of the algorithm introduced here. Finally, the linear-scaling properties of the algorithm are demonstrated by computing the lowest excitation energy of bacteriochlorophyll in solution. The largest systems considered in this work are of the same order of magnitude as a variety of widely studied pigment-protein complexes, opening up the possibility of studying their properties without having to resort to any semiclassical approximations to parts of the protein environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22493267','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22493267"><span id="translatedtitle">Linear-scaling <span class="hlt">time</span>-dependent density-functional theory beyond the Tamm-Dancoff approximation: Obtaining efficiency and <span class="hlt">accuracy</span> with in situ optimised local orbitals</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Zuehlsdorff, T. J. Payne, M. C.; Hine, N. D. M.; Haynes, P. D.</p> <p>2015-11-28</p> <p>We present a solution of the full <span class="hlt">time</span>-dependent density-functional theory (TDDFT) eigenvalue equation in the linear response formalism exhibiting a linear-scaling computational complexity with system size, without relying on the simplifying Tamm-Dancoff approximation (TDA). The implementation relies on representing the occupied and unoccupied subspaces with two different sets of in situ optimised localised functions, yielding a very compact and efficient representation of the transition density matrix of the excitation with the <span class="hlt">accuracy</span> associated with a systematic basis set. The TDDFT eigenvalue equation is solved using a preconditioned conjugate gradient algorithm that is very memory-efficient. The algorithm is validated on a small test molecule and a good agreement with results obtained from standard quantum chemistry packages is found, with the preconditioner yielding a significant improvement in convergence rates. The method developed in this work is then used to reproduce experimental results of the absorption spectrum of bacteriochlorophyll in an organic solvent, where it is demonstrated that the TDA fails to reproduce the main features of the low energy spectrum, while the full TDDFT equation yields results in good qualitative agreement with experimental data. Furthermore, the need for explicitly including parts of the solvent into the TDDFT calculations is highlighted, making the treatment of large system sizes necessary that are well within reach of the capabilities of the algorithm introduced here. Finally, the linear-scaling properties of the algorithm are demonstrated by computing the lowest excitation energy of bacteriochlorophyll in solution. The largest systems considered in this work are of the same order of magnitude as a variety of widely studied pigment-protein complexes, opening up the possibility of studying their properties without having to resort to any semiclassical approximations to parts of the protein environment.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21608709','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21608709"><span id="translatedtitle">Clinical Evaluation of Spatial <span class="hlt">Accuracy</span> of a Fusion Imaging Technique Combining Previously Acquired Computed Tomography and Real-<span class="hlt">Time</span> Ultrasound for Imaging of Liver Metastases</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hakime, Antoine Deschamps, Frederic; Garcia Marques de Carvalho, Enio; Teriitehau, Christophe; Auperin, Anne; De Baere, Thierry</p> <p>2011-04-15</p> <p>Purpose: This study was designed to evaluate the spatial <span class="hlt">accuracy</span> of matching volumetric computed tomography (CT) data of hepatic metastases with real-<span class="hlt">time</span> ultrasound (US) using a fusion imaging system (VNav) according to different clinical settings. Methods: Twenty-four patients with one hepatic tumor identified on enhanced CT and US were prospectively enrolled. A set of three landmarks markers was chosen on CT and US for image registration. US and CT images were then superimposed using the fusion imaging display mode. The difference in spatial location between the tumor visible on the CT and the US on the overlay images (reviewer no. 1, comment no. 2) was measured in the lateral, anterior-posterior, and vertical axis. The maximum difference (Dmax) was evaluated for different predictive factors.CT performed 1-30 days before registration versus immediately before. Use of general anesthesia for CT and US versus no anesthesia.Anatomic landmarks versus landmarks that include at least one nonanatomic structure, such as a cyst or a calcificationResultsOverall, Dmax was 11.53 {+-} 8.38 mm. Dmax was 6.55 {+-} 7.31 mm with CT performed immediately before VNav versus 17.4 {+-} 5.18 with CT performed 1-30 days before (p < 0.0001). Dmax was 7.05 {+-} 6.95 under general anesthesia and 16.81 {+-} 6.77 without anesthesia (p < 0.0015). Landmarks including at least one nonanatomic structure increase Dmax of 5.2 mm (p < 0.0001). The lowest Dmax (1.9 {+-} 1.4 mm) was obtained when CT and VNav were performed under general anesthesia, one immediately after the other. Conclusions: VNav is accurate when adequate clinical setup is carefully selected. Only under these conditions (reviewer no. 2), liver tumors not identified on US can be accurately targeted for biopsy or radiofrequency ablation using fusion imaging.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27485709','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27485709"><span id="translatedtitle">Evaluation of real-<span class="hlt">time</span> PCR assays and standard curve optimisation for enhanced <span class="hlt">accuracy</span> in quantification of Campylobacter environmental water isolates.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Gosselin-Théberge, Maxime; Taboada, Eduardo; Guy, Rebecca A</p> <p>2016-10-01</p> <p>Campylobacter is a major public health and economic burden in developed and developing countries. This study evaluated published real-<span class="hlt">time</span> PCR (qPCR) assays for detection of Campylobacter to enable selection of the best assays for quantification of C. spp. and C. jejuni in environmental water samples. A total of 9 assays were compared: three for thermotolerant C. spp. targeting the 16S rRNA and six for C. jejuni targeting different genes. These assays were tested in the wet-lab for specificity and sensitivity against a collection of 60, genetically diverse, Campylobacter isolates from environmental water. All three qPCR assays targeting C. spp. were positive when tested against the 60 isolates, whereas, assays targeting C. jejuni differed among each other in terms of specificity and sensitivity. Three C. jejuni-specific assays that demonstrated good specificity and sensitivity when tested in the wet-lab showed concordant results with in silico-predicted results obtained against a set of 211 C. jejuni and C. coli genome sequences. Two of the assays targeting C. spp. and C. jejuni were selected to compare DNA concentration estimation, using spectrophotometry and digital PCR (dPCR), in order to calibrate standard curves (SC) for greater <span class="hlt">accuracy</span> of qPCR-based quantification. Average differences of 0.56±0.12 and 0.51±0.11 log fold copies were observed between the spectrophotometry-based SC preparation and the dPCR preparation for C. spp. and C. jejuni, respectively, demonstrating an over-estimation of Campylobacter concentration when spectrophotometry was used to calibrate the DNA SCs. Our work showed differences in quantification of aquatic environmental isolates of Campylobacter between qPCR assays and method-specific bias in SC preparation. This study provided an objective analysis of qPCR assays targeting Campylobacter in the literature and provides a framework for evaluating novel assays. PMID:27485709</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_17");'>17</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li class="active"><span>19</span></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_19 --> <div id="page_20" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="381"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011AGUFM.G31A0939M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011AGUFM.G31A0939M&link_type=ABSTRACT"><span id="translatedtitle">GNSS <span class="hlt">Absolute</span> Antenna Calibration at the National Geodetic Survey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mader, G. L.; Bilich, A. L.; Geoghegan, C.</p> <p>2011-12-01</p> <p>Geodetic GNSS applications routinely demand millimeter precision and extremely high levels of <span class="hlt">accuracy</span>. To achieve these <span class="hlt">accuracies</span>, measurement and instrument biases at the centimeter to millimeter level must be understood. One of these biases is the antenna phase center, the apparent point of signal reception for a GNSS antenna. It has been well established that phase center patterns differ between antenna models and manufacturers; additional research suggests that the addition of a radome or the choice of antenna mount can significantly alter those a priori phase center patterns. For the more demanding GNSS positioning applications and especially in cases of mixed-antenna networks, it is all the more important to know antenna phase center variations as a function of both elevation and azimuth in the antenna reference frame and incorporate these models into analysis software. To help meet the needs of the high-precision GNSS community, the National Geodetic Survey (NGS) now operates an <span class="hlt">absolute</span> antenna calibration facility. Located in Corbin, Virginia, this facility uses field measurements and actual GNSS satellite signals to quantitatively determine the carrier phase advance/delay introduced by the antenna element. The NGS facility was built to serve traditional NGS constituents such as the surveying and geodesy communities, however calibration services are open and available to all GNSS users as the calibration schedule permits. All phase center patterns computed by this facility will be publicly available and disseminated in both the ANTEX and NGS formats. We describe the NGS calibration facility, and discuss the observation models and strategy currently used to generate NGS <span class="hlt">absolute</span> calibrations. We demonstrate that NGS <span class="hlt">absolute</span> phase center variation (PCV) patterns are consistent with published values determined by other <span class="hlt">absolute</span> antenna calibration facilities, and compare <span class="hlt">absolute</span> calibrations to the traditional NGS relative calibrations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23350305','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23350305"><span id="translatedtitle">Relational versus <span class="hlt">absolute</span> representation in categorization.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Edwards, Darren J; Pothos, Emmanuel M; Perlman, Amotz</p> <p>2012-01-01</p> <p>This study explores relational-like and <span class="hlt">absolute</span>-like representations in categorization. Although there is much evidence that categorization processes can involve information about both the particular physical properties of studied instances and abstract (relational) properties, there has been little work on the factors that lead to one kind of representation as opposed to the other. We tested 370 participants in 6 experiments, in which participants had to classify new items into predefined artificial categories. In 4 experiments, we observed a predominantly relational-like mode of classification, and in 2 experiments we observed a shift toward an <span class="hlt">absolute</span>-like mode of classification. These results suggest 3 factors that promote a relational-like mode of classification: fewer items per group, more training groups, and the presence of a <span class="hlt">time</span> delay. Overall, we propose that less information about the distributional properties of a category or weaker memory traces for the category exemplars (induced, e.g., by having smaller categories or a <span class="hlt">time</span> delay) can encourage relational-like categorization.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27581485','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27581485"><span id="translatedtitle">Transient <span class="hlt">absolute</span> robustness in stochastic biochemical networks.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Enciso, German A</p> <p>2016-08-01</p> <p><span class="hlt">Absolute</span> robustness allows biochemical networks to sustain a consistent steady-state output in the face of protein concentration variability from cell to cell. This property is structural and can be determined from the topology of the network alone regardless of rate parameters. An important question regarding these systems is the effect of discrete biochemical noise in the dynamical behaviour. In this paper, a variable freezing technique is developed to show that under mild hypotheses the corresponding stochastic system has a transiently robust behaviour. Specifically, after finite <span class="hlt">time</span> the distribution of the output approximates a Poisson distribution, centred around the deterministic mean. The approximation becomes increasingly accurate, and it holds for increasingly long finite <span class="hlt">times</span>, as the total protein concentrations grow to infinity. In particular, the stochastic system retains a transient, <span class="hlt">absolutely</span> robust behaviour corresponding to the deterministic case. This result contrasts with the long-term dynamics of the stochastic system, which eventually must undergo an extinction event that eliminates robustness and is completely different from the deterministic dynamics. The transiently robust behaviour may be sufficient to carry out many forms of robust signal transduction and cellular decision-making in cellular organisms. PMID:27581485</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70046799','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70046799"><span id="translatedtitle">Alaska national hydrography dataset positional <span class="hlt">accuracy</span> assessment study</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Arundel, Samantha; Yamamoto, Kristina H.; Constance, Eric; Mantey, Kim; Vinyard-Houx, Jeremy</p> <p>2013-01-01</p> <p>Initial visual assessments Wide range in the quality of fit between features in NHD and these new image sources. No statistical analysis has been performed to actually quantify <span class="hlt">accuracy</span> Determining <span class="hlt">absolute</span> <span class="hlt">accuracy</span> is cost prohibitive (must collect independent, well defined test points) Quantitative analysis of relative positional error is feasible.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016JCAP...08..060V&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016JCAP...08..060V&link_type=ABSTRACT"><span id="translatedtitle">Cosmology with negative <span class="hlt">absolute</span> temperatures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony</p> <p>2016-08-01</p> <p>Negative <span class="hlt">absolute</span> temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w < ‑1) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19730021662','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19730021662"><span id="translatedtitle">Apparatus for <span class="hlt">absolute</span> pressure measurement</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hecht, R. (Inventor)</p> <p>1969-01-01</p> <p>An <span class="hlt">absolute</span> pressure sensor (e.g., the diaphragm of a capacitance manometer) was subjected to a superimposed potential to effectively reduce the mechanical stiffness of the sensor. This substantially increases the sensitivity of the sensor and is particularly useful in vacuum gauges. An oscillating component of the superimposed potential induced vibrations of the sensor. The phase of these vibrations with respect to that of the oscillating component was monitored, and served to initiate an automatic adjustment of the static component of the superimposed potential, so as to bring the sensor into resonance at the frequency of the oscillating component. This establishes a selected sensitivity for the sensor, since a definite relationship exists between resonant frequency and sensitivity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JCAP...08..060V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JCAP...08..060V"><span id="translatedtitle">Cosmology with negative <span class="hlt">absolute</span> temperatures</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony</p> <p>2016-08-01</p> <p>Negative <span class="hlt">absolute</span> temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w < -1) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFM.T13A2965T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFM.T13A2965T"><span id="translatedtitle">The Application of Optimisation Methods to Constrain <span class="hlt">Absolute</span> Plate Motions</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Tetley, M. G.; Williams, S.; Hardy, S.; Müller, D.</p> <p>2015-12-01</p> <p>Plate tectonic reconstructions are an excellent tool for understanding the configuration and behaviour of continents through <span class="hlt">time</span> on both global and regional scales, and are relatively well understood back to ~200 Ma. However, many of these models represent only relative motions between continents, providing little information of <span class="hlt">absolute</span> tectonic motions and their relationship with the deep Earth. Significant issues exist in solving this problem, including how to combine constraints from multiple, diverse data into a unified model of <span class="hlt">absolute</span> plate motions; and how to address uncertainties both in the available data, and in the assumptions involved in this process (e.g. hotspot motion, true polar wander). In deep <span class="hlt">time</span> (pre-Pangea breakup), plate reconstructions rely more heavily on paleomagnetism, but these data often imply plate velocities much larger than those observed since the breakup of the supercontinent Pangea where plate velocities are constrained by the seafloor spreading record. Here we present two complementary techniques to address these issues, applying parallelized numerical methods to quantitatively investigate <span class="hlt">absolute</span> plate motions through <span class="hlt">time</span>. Firstly, we develop a data-fit optimized global <span class="hlt">absolute</span> reference frame constrained by kinematic reconstruction data, hotspot-trail observations, and trench migration statistics. Secondly we calculate optimized paleomagnetic data-derived apparent polar wander paths (APWPs) for both the Phanerozoic and Precambrian. Paths are generated from raw pole data with optimal spatial and temporal pole configurations calculated using all known uncertainties and quality criteria to produce velocity-optimized <span class="hlt">absolute</span> motion paths through deep <span class="hlt">time</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016APS..APRB16007K&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2016APS..APRB16007K&link_type=ABSTRACT"><span id="translatedtitle"><span class="hlt">Absolute</span> Electron Extraction Efficiency of Liquid Xenon</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kamdin, Katayun; Mizrachi, Eli; Morad, James; Sorensen, Peter</p> <p>2016-03-01</p> <p>Dual phase liquid/gas xenon <span class="hlt">time</span> projection chambers (TPCs) currently set the world's most sensitive limits on weakly interacting massive particles (WIMPs), a favored dark matter candidate. These detectors rely on extracting electrons from liquid xenon into gaseous xenon, where they produce proportional scintillation. The proportional scintillation from the extracted electrons serves to internally amplify the WIMP signal; even a single extracted electron is detectable. Credible dark matter searches can proceed with electron extraction efficiency (EEE) lower than 100%. However, electrons systematically left at the liquid/gas boundary are a concern. Possible effects include spontaneous single or multi-electron proportional scintillation signals in the gas, or charging of the liquid/gas interface or detector materials. Understanding EEE is consequently a serious concern for this class of rare event search detectors. Previous EEE measurements have mostly been relative, not <span class="hlt">absolute</span>, assuming efficiency plateaus at 100%. I will present an <span class="hlt">absolute</span> EEE measurement with a small liquid/gas xenon TPC test bed located at Lawrence Berkeley National Laboratory.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012AGUFM.V11F..06V','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012AGUFM.V11F..06V"><span id="translatedtitle">Measurement of <span class="hlt">Absolute</span> Carbon Isotope Ratios: Mechanisms and Implications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Vogel, J. S.; Giacomo, J. A.; Dueker, S. R.</p> <p>2012-12-01</p> <p>An accelerator mass spectrometer (AMS) produced <span class="hlt">absolute</span> isotope ratio measurements for 14C/13C as tested against >500 samples of NIST SRM-4990-C (OxII 14C standard) to an <span class="hlt">accuracy</span> of 2.2±0.6‰ over a period of one year with measurements made to 1% counting statistics. The spectrometer is not maximized for 13C/12C, but measured ∂13C to 0.4±0.1‰ <span class="hlt">accuracy</span>, with known methods for improvement. An AMS produces elemental anions from a sputter ion source and includes a charge-changing collision in a gas cell to isolate the rare 14C from the common isotopes and molecular isobars. Both these physical processes have been modeled to determine the parameters providing such <span class="hlt">absolute</span> measures. Neutral resonant ionization in a cesium plasma produces mass-independent ionization, while velocity dependent charge-state distributions in gas collisions produce relative ion beam intensities that are linear in mass at specific collision energies. The mechanisms are not specific to carbon isotopes, but stand alone <span class="hlt">absolute</span> IRMS (AIR-MS) instruments have not yet been made. Aside from the obvious applications in metrology, AIR-MS is particularly valuable in coupled separatory MS because no internal or external standards are required. Sample definition processes can be compared, even if no exact standard reference sample exists. Isotope dilution measurements do not require standards matching the dilution end-points and can be made over an extended, even extrapolated, range.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=205388','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=205388"><span id="translatedtitle"><span class="hlt">Accuracy</span>, precision and response <span class="hlt">time</span> of consumer fork, remote digital probe and disposable indicator thermometers for cooked ground beef patties and chicken breasts</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>Nine different commercially available instant-read consumer thermometers (forks, remotes, digital probe and disposable color change indicators) were tested for <span class="hlt">accuracy</span> and precision compared to a calibrated thermocouple in 80 percent and 90 percent lean ground beef patties, and boneless and bone-in...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=no+AND+words+AND+found+OR+water&pg=4&id=EJ1000163','ERIC'); return false;" href="http://eric.ed.gov/?q=no+AND+words+AND+found+OR+water&pg=4&id=EJ1000163"><span id="translatedtitle">Lexical and Sub-Lexical Effects on <span class="hlt">Accuracy</span>, Reaction <span class="hlt">Time</span> and Response Duration: Impaired and Typical Word and Pseudoword Reading in a Transparent Orthography</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Davies, Robert; Rodriguez-Ferreiro, Javier; Suarez, Paz; Cuetos, Fernando</p> <p>2013-01-01</p> <p>In an opaque orthography like English, phonological coding errors are a prominent feature of dyslexia. In a transparent orthography like Spanish, reading difficulties are characterized by slower reading speed rather than reduced <span class="hlt">accuracy</span>. In previous research, the reading speed deficit was revealed by asking children to read lists of words.…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JPhCS.633a2080F','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JPhCS.633a2080F"><span id="translatedtitle">Mathematical Model for <span class="hlt">Absolute</span> Magnetic Measuring Systems in Industrial Applications</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Fügenschuh, Armin; Fügenschuh, Marzena; Ludszuweit, Marina; Mojsic, Aleksandar; Sokół, Joanna</p> <p>2015-09-01</p> <p>Scales for measuring systems are either based on incremental or <span class="hlt">absolute</span> measuring methods. Incremental scales need to initialize a measurement cycle at a reference point. From there, the position is computed by counting increments of a periodic graduation. <span class="hlt">Absolute</span> methods do not need reference points, since the position can be read directly from the scale. The positions on the complete scales are encoded using two incremental tracks with different graduation. We present a new method for <span class="hlt">absolute</span> measuring using only one track for position encoding up to micrometre range. Instead of the common perpendicular magnetic areas, we use a pattern of trapezoidal magnetic areas, to store more complex information. For positioning, we use the magnetic field where every position is characterized by a set of values measured by a hall sensor array. We implement a method for reconstruction of <span class="hlt">absolute</span> positions from the set of unique measured values. We compare two patterns with respect to uniqueness, <span class="hlt">accuracy</span>, stability and robustness of positioning. We discuss how stability and robustness are influenced by different errors during the measurement in real applications and how those errors can be compensated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016NIMPA.812...24S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016NIMPA.812...24S"><span id="translatedtitle">Determination of <span class="hlt">absolute</span> internal conversion coefficients using the SAGE spectrometer</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Sorri, J.; Greenlees, P. T.; Papadakis, P.; Konki, J.; Cox, D. M.; Auranen, K.; Partanen, J.; Sandzelius, M.; Pakarinen, J.; Rahkila, P.; Uusitalo, J.; Herzberg, R.-D.; Smallcombe, J.; Davies, P. J.; Barton, C. J.; Jenkins, D. G.</p> <p>2016-03-01</p> <p>A non-reference based method to determine internal conversion coefficients using the SAGE spectrometer is carried out for transitions in the nuclei of 154Sm, 152Sm and 166Yb. The Normalised-Peak-to-Gamma method is in general an efficient tool to extract internal conversion coefficients. However, in many cases the required well-known reference transitions are not available. The data analysis steps required to determine <span class="hlt">absolute</span> internal conversion coefficients with the SAGE spectrometer are presented. In addition, several background suppression methods are introduced and an example of how ancillary detectors can be used to select specific reaction products is given. The results obtained for ground-state band E2 transitions show that the <span class="hlt">absolute</span> internal conversion coefficients can be extracted using the methods described with a reasonable <span class="hlt">accuracy</span>. In some cases of less intense transitions only an upper limit for the internal conversion coefficient could be given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19910042706&hterms=censorship&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcensorship','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19910042706&hterms=censorship&qs=N%3D0%26Ntk%3DAll%26Ntx%3Dmode%2Bmatchall%26Ntt%3Dcensorship"><span id="translatedtitle"><span class="hlt">Absolute</span> magnitude calibration using trigonometric parallax - Incomplete, spectroscopic samples</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Ratnatunga, Kavan U.; Casertano, Stefano</p> <p>1991-01-01</p> <p>A new numerical algorithm is used to calibrate the <span class="hlt">absolute</span> magnitude of spectroscopically selected stars from their observed trigonometric parallax. This procedure, based on maximum-likelihood estimation, can retrieve unbiased estimates of the intrinsic <span class="hlt">absolute</span> magnitude and its dispersion even from incomplete samples suffering from selection biases in apparent magnitude and color. It can also make full use of low <span class="hlt">accuracy</span> and negative parallaxes and incorporate censorship on reported parallax values. Accurate error estimates are derived for each of the fitted parameters. The algorithm allows an a posteriori check of whether the fitted model gives a good representation of the observations. The procedure is described in general and applied to both real and simulated data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2011stis.rept....1P','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2011stis.rept....1P"><span id="translatedtitle">Wavelength Calibration <span class="hlt">Accuracy</span> for the STIS CCD and MAMA Modes</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Pascucci, Ilaria; Hodge, Phil; Proffitt, Charles R.; Ayres, T.</p> <p>2011-03-01</p> <p>Two calibration programs were carried out to determine the <span class="hlt">accuracy</span> of the wavelength solutions for the most used STIS CCD and MAMA modes after Servicing Mission 4. We report here on the analysis of this dataset and show that the STIS wavelength solution has not changed after SM4. We also show that a typical <span class="hlt">accuracy</span> for the <span class="hlt">absolute</span> wavelength zero-points is 0.1 pixels while the relative wavelength <span class="hlt">accuracy</span> is 0.2 pixels.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012EGUGA..14.3080M&link_type=ABSTRACT','NASAADS'); return false;" href="http://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2012EGUGA..14.3080M&link_type=ABSTRACT"><span id="translatedtitle"><span class="hlt">Absolute</span> GNSS Antenna Calibration at the National Geodetic Survey</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mader, G.; Bilich, A.; Geoghegan, C.</p> <p>2012-04-01</p> <p>Geodetic GNSS applications routinely demand millimeter precision and extremely high levels of <span class="hlt">accuracy</span>. To achieve these <span class="hlt">accuracies</span>, measurement and instrument biases at the centimeter to millimeter level must be understood. One of these biases is the antenna phase center, the apparent point of signal reception for a GNSS antenna. It has been well established that phase center patterns differ between antenna models and manufacturers; additional research suggests that the addition of a radome or the choice of antenna mount can significantly alter those a priori phase center patterns. For the more demanding GNSS positioning applications and especially in cases of mixed-antenna networks, it is all the more important to know antenna phase center variations as a function of both elevation and azimuth in the antenna reference frame and incorporate these models into analysis software. To help meet the needs of the high-precision GNSS community, the National Geodetic Survey (NGS) now operates an <span class="hlt">absolute</span> antenna calibration facility. Located in Corbin, Virginia, this facility uses field measurements and actual GNSS satellite signals to quantitatively determine the carrier phase advance/delay introduced by the antenna element. The NGS facility was built to serve traditional NGS constituents such as the surveying and geodesy communities, however calibration services are open and available to all GNSS users as the calibration schedule permits. All phase center patterns computed by this facility will be publicly available and disseminated in both the ANTEX and NGS formats. We describe the NGS calibration facility, and discuss the observation models and strategy currently used to generate NGS <span class="hlt">absolute</span> calibrations. We demonstrate that NGS <span class="hlt">absolute</span> phase center variation (PCV) patterns are consistent with published values determined by other <span class="hlt">absolute</span> antenna calibration facilities, and outline future planned refinements to the system.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3007289','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3007289"><span id="translatedtitle"><span class="hlt">Absolute</span> configuration of isovouacapenol C</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Fun, Hoong-Kun; Yodsaoue, Orapun; Karalai, Chatchanok; Chantrapromma, Suchada</p> <p>2010-01-01</p> <p>The title compound, C27H34O5 {systematic name: (4aR,5R,6R,6aS,7R,11aS,11bR)-4a,6-dihy­droxy-4,4,7,11b-tetra­methyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodeca­hydro­phenanthro[3,2-b]furan-5-yl benzoate}, is a cassane furan­oditerpene, which was isolated from the roots of Caesalpinia pulcherrima. The three cyclo­hexane rings are trans fused: two of these are in chair conformations with the third in a twisted half-chair conformation, whereas the furan ring is almost planar (r.m.s. deviation = 0.003 Å). An intra­molecular C—H⋯O inter­action generates an S(6) ring. The <span class="hlt">absolute</span> configurations of the stereogenic centres at positions 4a, 5, 6, 6a, 7, 11a and 11b are R, R, R, S, R, S and R, respectively. In the crystal, mol­ecules are linked into infinite chains along [010] by O—H⋯O hydrogen bonds. C⋯O [3.306 (2)–3.347 (2) Å] short contacts and C—H⋯π inter­actions also occur. PMID:21588364</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ChJOL..34.1383Y','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ChJOL..34.1383Y"><span id="translatedtitle"><span class="hlt">Absolute</span> geostrophic currents in global tropical oceans</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Yang, Lina; Yuan, Dongliang</p> <p>2016-11-01</p> <p>A set of <span class="hlt">absolute</span> geostrophic current (AGC) data for the period January 2004 to December 2012 are calculated using the P-vector method based on monthly gridded Argo profiles in the world tropical oceans. The AGCs agree well with altimeter geostrophic currents, Ocean Surface Current Analysis-Real <span class="hlt">time</span> currents, and moored current-meter measurements at 10-m depth, based on which the classical Sverdrup circulation theory is evaluated. Calculations have shown that errors of wind stress calculation, AGC transport, and depth ranges of vertical integration cannot explain non-Sverdrup transport, which is mainly in the subtropical western ocean basins and equatorial currents near the Equator in each ocean basin (except the North Indian Ocean, where the circulation is dominated by monsoons). The identified non-Sverdrup transport is thereby robust and attributed to the joint effect of baroclinicity and relief of the bottom (JEBAR) and mesoscale eddy nonlinearity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140010486','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140010486"><span id="translatedtitle"><span class="hlt">Absolute</span> Calibration of Optical Satellite Sensors Using Libya 4 Pseudo Invariant Calibration Site</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Mishra, Nischal; Helder, Dennis; Angal, Amit; Choi, Jason; Xiong, Xiaoxiong</p> <p>2014-01-01</p> <p>The objective of this paper is to report the improvements in an empirical <span class="hlt">absolute</span> calibration model developed at South Dakota State University using Libya 4 (+28.55 deg, +23.39 deg) pseudo invariant calibration site (PICS). The approach was based on use of the Terra MODIS as the radiometer to develop an <span class="hlt">absolute</span> calibration model for the spectral channels covered by this instrument from visible to shortwave infrared. Earth Observing One (EO-1) Hyperion, with a spectral resolution of 10 nm, was used to extend the model to cover visible and near-infrared regions. A simple Bidirectional Reflectance Distribution function (BRDF) model was generated using Terra Moderate Resolution Imaging Spectroradiometer (MODIS) observations over Libya 4 and the resulting model was validated with nadir data acquired from satellite sensors such as Aqua MODIS and Landsat 7 (L7) Enhanced Thematic Mapper (ETM+). The improvements in the <span class="hlt">absolute</span> calibration model to account for the BRDF due to off-nadir measurements and annual variations in the atmosphere are summarized. BRDF models due to off-nadir viewing angles have been derived using the measurements from EO-1 Hyperion. In addition to L7 ETM+, measurements from other sensors such as Aqua MODIS, UK-2 Disaster Monitoring Constellation (DMC), ENVISAT Medium Resolution Imaging Spectrometer (MERIS) and Operational Land Imager (OLI) onboard Landsat 8 (L8), which was launched in February 2013, were employed to validate the model. These satellite sensors differ in terms of the width of their spectral bandpasses, overpass <span class="hlt">time</span>, off-nadir-viewing capabilities, spatial resolution and temporal revisit <span class="hlt">time</span>, etc. The results demonstrate that the proposed empirical calibration model has <span class="hlt">accuracy</span> of the order of 3% with an uncertainty of about 2% for the sensors used in the study.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_18");'>18</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li class="active"><span>20</span></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_20 --> <div id="page_21" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="401"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26459122','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26459122"><span id="translatedtitle">Stable measures of number sense <span class="hlt">accuracy</span> in math learning disability: Is it <span class="hlt">time</span> to proceed from basic science to clinical application?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Júlio-Costa, Annelise; Starling-Alves, Isabella; Lopes-Silva, Júlia Beatriz; Wood, Guilherme; Haase, Vitor Geraldi</p> <p>2015-12-01</p> <p>Math learning disability (MLD) or developmental dyscalculia is a highly prevalent and persistent difficulty in learning arithmetic that may be explained by different cognitive mechanisms. The <span class="hlt">accuracy</span> of the number sense has been implicated by some evidence as a core deficit in MLD. However, research on this topic has been mainly conducted in demographically selected samples, using arbitrary cut-off scores to characterize MLD. The clinical relevance of the association between number sense and MLD remains to be investigated. In this study, we aimed at assessing the stability of a number sense <span class="hlt">accuracy</span> measure (w) across five experimental sessions, in two clinically defined cases of MLD. Stable measures of number sense <span class="hlt">accuracy</span> estimate are required to clinically characterize subtypes of MLD and to make theoretical inferences regarding the underlying cognitive mechanisms. G. A. was a 10-year-old boy with MLD in the context of dyslexia and phonological processing impairment and his performance remained steadily in the typical scores range. The performance of H. V., a 9-year-old girl with MLD associated with number sense inaccuracy, remained consistently impaired across measurements, with a nonsignificant tendency to worsen. Qualitatively, H. V.'s performance was also characterized by greater variability across sessions. Concomitant clinical observations suggested that H. V.'s difficulties could be aggravated by developing symptoms of mathematics anxiety. Results in these two cases are in line with the hypotheses that at least two reliable patterns of cognitive impairment may underlie math learning difficulties in MLD, one related to number sense inaccuracy and the other to phonological processing impairment. Additionally, it indicates the need for more translational research in order to examine the usefulness and validity of theoretical advances in numerical cognition to the clinical neuropsychological practice with MLD. PMID:26459122</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26459122','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26459122"><span id="translatedtitle">Stable measures of number sense <span class="hlt">accuracy</span> in math learning disability: Is it <span class="hlt">time</span> to proceed from basic science to clinical application?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Júlio-Costa, Annelise; Starling-Alves, Isabella; Lopes-Silva, Júlia Beatriz; Wood, Guilherme; Haase, Vitor Geraldi</p> <p>2015-12-01</p> <p>Math learning disability (MLD) or developmental dyscalculia is a highly prevalent and persistent difficulty in learning arithmetic that may be explained by different cognitive mechanisms. The <span class="hlt">accuracy</span> of the number sense has been implicated by some evidence as a core deficit in MLD. However, research on this topic has been mainly conducted in demographically selected samples, using arbitrary cut-off scores to characterize MLD. The clinical relevance of the association between number sense and MLD remains to be investigated. In this study, we aimed at assessing the stability of a number sense <span class="hlt">accuracy</span> measure (w) across five experimental sessions, in two clinically defined cases of MLD. Stable measures of number sense <span class="hlt">accuracy</span> estimate are required to clinically characterize subtypes of MLD and to make theoretical inferences regarding the underlying cognitive mechanisms. G. A. was a 10-year-old boy with MLD in the context of dyslexia and phonological processing impairment and his performance remained steadily in the typical scores range. The performance of H. V., a 9-year-old girl with MLD associated with number sense inaccuracy, remained consistently impaired across measurements, with a nonsignificant tendency to worsen. Qualitatively, H. V.'s performance was also characterized by greater variability across sessions. Concomitant clinical observations suggested that H. V.'s difficulties could be aggravated by developing symptoms of mathematics anxiety. Results in these two cases are in line with the hypotheses that at least two reliable patterns of cognitive impairment may underlie math learning difficulties in MLD, one related to number sense inaccuracy and the other to phonological processing impairment. Additionally, it indicates the need for more translational research in order to examine the usefulness and validity of theoretical advances in numerical cognition to the clinical neuropsychological practice with MLD.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ISPAr41B7..859N','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ISPAr41B7..859N"><span id="translatedtitle">Evaluation of Relative Geometric <span class="hlt">Accuracy</span> of Terrasar-X by Pixel Matching Methodology</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Nonaka, T.; Asaka, T.; Iwashita, K.</p> <p>2016-06-01</p> <p>Recently, high-resolution commercial SAR satellites with several meters of resolutions are widely utilized for various applications and disaster monitoring is one of the commonly applied areas. The information about the flooding situation and ground displacement was rapidly announced to the public after the Great East Japan Earthquake 2011. One of the studies reported the displacement in Tohoku region by the pixel matching methodology using both pre- and post- event TerraSAR-X data, and the validated <span class="hlt">accuracy</span> was about 30 cm at the GEONET reference points. In order to discuss the spatial distribution of the displacement, we need to evaluate the relative <span class="hlt">accuracy</span> of the displacement in addition to the <span class="hlt">absolute</span> <span class="hlt">accuracy</span>. In the previous studies, our study team evaluated the <span class="hlt">absolute</span> 2D geo-location <span class="hlt">accuracy</span> of the TerraSAR-X ortho-rectified EEC product for both flat and mountain areas. Therefore, the purpose of the current study was to evaluate the spatial and temporal relative geo-location <span class="hlt">accuracies</span> of the product by considering the displacement of the fixed point as the relative geo-location <span class="hlt">accuracy</span>. Firstly, by utilizing TerraSAR-X StripMap dataset, the pixel matching method for estimating the displacement with sub-pixel level was developed. Secondly, the validity of the method was confirmed by comparing with GEONET data. We confirmed that the <span class="hlt">accuracy</span> of the displacement for X and Y direction was in agreement with the previous studies. Subsequently, the methodology was applied to 20 pairs of data set for areas of Tokyo Ota-ku and Kawasaki-shi, and the displacement of each pair was evaluated. It was revealed that the <span class="hlt">time</span> series displacement rate had the seasonal trend and seemed to be related to atmospheric delay.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1981PhDT........23Z','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1981PhDT........23Z"><span id="translatedtitle">a Portable Apparatus for <span class="hlt">Absolute</span> Measurements of the Earth's Gravity.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Zumberge, Mark Andrew</p> <p></p> <p>We have developed a new, portable apparatus for making <span class="hlt">absolute</span> measurements of the acceleration due to the earth's gravity. We use the method of interferometrically determining the acceleration of a freely falling corner -cube prism. The falling object is surrounded by a chamber which is driven vertically inside a fixed vacuum chamber. This falling chamber is servoed to track the falling corner -cube to shield it from drag due to background gas. In addition, the drag-free falling chamber removes the need for a magnetic release, shields the falling object from electrostatic forces, and provides a means of both gently arresting the falling object and quickly returning it to its start position, to allow rapid acquisition of data. A synthesized long period isolation device reduces the noise due to seismic oscillations. A new type of Zeeman laser is used as the light source in the interferometer, and is compared with the wavelength of an iodine stabilized laser. The <span class="hlt">times</span> of occurrence of 45 interference fringes are measured to within 0.2 nsec over a 20 cm drop and are fit to a quadratic by an on-line minicomputer. 150 drops can be made in ten minutes resulting in a value of g having a precision of 3 to 6 parts in 10('9). Systematic errors have been determined to be less than 5 parts in 10('9) through extensive tests. Three months of gravity data have been obtained with a reproducibility ranging from 5 to 10 parts in 10('9). The apparatus has been designed to be easily portable. Field measurements are planned for the immediate future. An <span class="hlt">accuracy</span> of 6 parts in 10('9) corresponds to a height sensitivity of 2 cm. Vertical motions in the earth's crust and tectonic density changes that may precede earthquakes are to be investigated using this apparatus.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70025069','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70025069"><span id="translatedtitle"><span class="hlt">Absolute</span> irradiance of the Moon for on-orbit calibration</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Stone, T.C.; Kieffer, H.H.; ,</p> <p>2002-01-01</p> <p>The recognized need for on-orbit calibration of remote sensing imaging instruments drives the ROLO project effort to characterize the Moon for use as an <span class="hlt">absolute</span> radiance source. For over 5 years the ground-based ROLO telescopes have acquired spatially-resolved lunar images in 23 VNIR (Moon diameter ???500 pixels) and 9 SWIR (???250 pixels) passbands at phase angles within ??90 degrees. A numerical model for lunar irradiance has been developed which fits hundreds of ROLO images in each band, corrected for atmospheric extinction and calibrated to <span class="hlt">absolute</span> radiance, then integrated to irradiance. The band-coupled extinction algorithm uses absorption spectra of several gases and aerosols derived from MODTRAN to fit <span class="hlt">time</span>-dependent component abundances to nightly observations of standard stars. The <span class="hlt">absolute</span> radiance scale is based upon independent telescopic measurements of the star Vega. The fitting process yields uncertainties in lunar relative irradiance over small ranges of phase angle and the full range of lunar libration well under 0.5%. A larger source of uncertainty enters in the <span class="hlt">absolute</span> solar spectral irradiance, especially in the SWIR, where solar models disagree by up to 6%. Results of ROLO model direct comparisons to spacecraft observations demonstrate the ability of the technique to track sensor responsivity drifts to sub-percent precision. Intercomparisons among instruments provide key insights into both calibration issues and the <span class="hlt">absolute</span> scale for lunar irradiance.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19860059673&hterms=ram&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dram','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19860059673&hterms=ram&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D70%26Ntt%3Dram"><span id="translatedtitle">STS-9 Shuttle grow - Ram angle effect and <span class="hlt">absolute</span> intensities</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Swenson, G. R.; Mende, S. B.; Clifton, K. S.</p> <p>1986-01-01</p> <p>Visible imagery from Space Shuttle mission STS-9 (Spacelab 1) has been analyzed for the ram angle effect and the <span class="hlt">absolute</span> intensity of glow. The data are compared with earlier measurements and the anomalous high intensities at large ram angles are confirmed. <span class="hlt">Absolute</span> intensities of the ram glow on the shuttle tile, at 6563 A, are observed to be about 20 <span class="hlt">times</span> more intense than those measured on the AE-E spacecraft. Implications of these observations for an existing theory of glow involving NO2 are presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ars.usda.gov/research/publications/publication/?seqNo115=318935','TEKTRAN'); return false;" href="http://www.ars.usda.gov/research/publications/publication/?seqNo115=318935"><span id="translatedtitle"><span class="hlt">Absolute</span> configurations of zingiberenols isolated from ginger (Zingiber officinale) rhizomes</span></a></p> <p><a target="_blank" href="http://www.ars.usda.gov/services/TekTran.htm">Technology Transfer Automated Retrieval System (TEKTRAN)</a></p> <p></p> <p></p> <p>The sesquiterpene alcohol zingiberenol, or 1,10-bisaboladien-3-ol, was isolated some <span class="hlt">time</span> ago from ginger, Zingiber officinale, rhizomes, but its <span class="hlt">absolute</span> configuration had not been determined. With three chiral centers present in the molecule, zingiberenol can exist in eight stereoisomeric forms. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20060030502&hterms=Herring&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DHerring','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20060030502&hterms=Herring&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DHerring"><span id="translatedtitle">Urey: to measure the <span class="hlt">absolute</span> age of Mars</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Randolph, J. E.; Plescia, J.; Bar-Cohen, Y.; Bartlett, P.; Bickler, D.; Carlson, R.; Carr, G.; Fong, M.; Gronroos, H.; Guske, P. J.; Herring, M.; Javadi, H.; Johnson, D. W.; Larson, T.; Malaviarachchi, K.; Sherrit, S.; Stride, S.; Trebi-Ollennu, A.; Warwick, R.</p> <p>2003-01-01</p> <p>UREY, a proposed NASA Mars Scout mission will, for the first <span class="hlt">time</span>, measure the <span class="hlt">absolute</span> 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.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=Happiness&pg=7&id=EJ804151','ERIC'); return false;" href="http://eric.ed.gov/?q=Happiness&pg=7&id=EJ804151"><span id="translatedtitle"><span class="hlt">Absolute</span> Income, Relative Income, and Happiness</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ball, Richard; Chernova, Kateryna</p> <p>2008-01-01</p> <p>This paper uses data from the World Values Survey to investigate how an individual's self-reported happiness is related to (i) the level of her income in <span class="hlt">absolute</span> terms, and (ii) the level of her income relative to other people in her country. The main findings are that (i) both <span class="hlt">absolute</span> and relative income are positively and significantly…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ853800.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ853800.pdf"><span id="translatedtitle">Investigating <span class="hlt">Absolute</span> Value: A Real World Application</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Kidd, Margaret; Pagni, David</p> <p>2009-01-01</p> <p>Making connections between various representations is important in mathematics. In this article, the authors discuss the numeric, algebraic, and graphical representations of sums of <span class="hlt">absolute</span> values of linear functions. The initial explanations are accessible to all students who have experience graphing and who understand that <span class="hlt">absolute</span> value simply…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=RHS+AND+15&pg=4&id=EJ249107','ERIC'); return false;" href="http://eric.ed.gov/?q=RHS+AND+15&pg=4&id=EJ249107"><span id="translatedtitle">Preschoolers' Success at Coding <span class="hlt">Absolute</span> Size Values.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Russell, James</p> <p>1980-01-01</p> <p>Forty-five 2-year-old and forty-five 3-year-old children coded relative and <span class="hlt">absolute</span> sizes using 1.5-inch, 6-inch, and 18-inch cardboard squares. Results indicate that <span class="hlt">absolute</span> coding is possible for children of this age. (Author/RH)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=standard+AND+deviation&pg=2&id=EJ1050985','ERIC'); return false;" href="http://eric.ed.gov/?q=standard+AND+deviation&pg=2&id=EJ1050985"><span id="translatedtitle">Introducing the Mean <span class="hlt">Absolute</span> Deviation "Effect" Size</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Gorard, Stephen</p> <p>2015-01-01</p> <p>This paper revisits the use of effect sizes in the analysis of experimental and similar results, and reminds readers of the relative advantages of the mean <span class="hlt">absolute</span> deviation as a measure of variation, as opposed to the more complex standard deviation. The mean <span class="hlt">absolute</span> deviation is easier to use and understand, and more tolerant of extreme…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/1261596','DOE-PATENT-XML'); return false;" href="http://www.osti.gov/scitech/servlets/purl/1261596"><span id="translatedtitle">Monolithically integrated <span class="hlt">absolute</span> frequency comb laser system</span></a></p> <p><a target="_blank" href="http://www.osti.gov/doepatents">DOEpatents</a></p> <p>Wanke, Michael C.</p> <p>2016-07-12</p> <p>Rather than down-convert optical frequencies, a QCL laser system directly generates a THz frequency comb in a compact monolithically integrated chip that can be locked to an <span class="hlt">absolute</span> frequency without the need of a frequency-comb synthesizer. The monolithic, <span class="hlt">absolute</span> frequency comb can provide a THz frequency reference and tool for high-resolution broad band spectroscopy.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19880033615&hterms=VALUE+ABSOLUTE&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DVALUE%2BABSOLUTE','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19880033615&hterms=VALUE+ABSOLUTE&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D40%26Ntt%3DVALUE%2BABSOLUTE"><span id="translatedtitle"><span class="hlt">Absolute</span> instability of the Gaussian wake profile</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Hultgren, Lennart S.; Aggarwal, Arun K.</p> <p>1987-01-01</p> <p>Linear parallel-flow stability theory has been used to investigate the effect of viscosity on the local <span class="hlt">absolute</span> instability of a family of wake profiles with a Gaussian velocity distribution. The type of local instability, i.e., convective or <span class="hlt">absolute</span>, is determined by the location of a branch-point singularity with zero group velocity of the complex dispersion relation for the instability waves. The effects of viscosity were found to be weak for values of the wake Reynolds number, based on the center-line velocity defect and the wake half-width, larger than about 400. <span class="hlt">Absolute</span> instability occurs only for sufficiently large values of the center-line wake defect. The critical value of this parameter increases with decreasing wake Reynolds number, thereby indicating a shrinking region of <span class="hlt">absolute</span> instability with decreasing wake Reynolds number. If backflow is not allowed, <span class="hlt">absolute</span> instability does not occur for wake Reynolds numbers smaller than about 38.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5008602','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=5008602"><span id="translatedtitle">The <span class="hlt">accuracy</span> with which the 5 <span class="hlt">times</span> sit-to-stand test, versus gait speed, can identify poor exercise tolerance in patients with COPD</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Bernabeu-Mora, Roberto; Medina-Mirapeix, Francesc; Llamazares-Herrán, Eduardo; de Oliveira-Sousa, Silvana Loana; Sánchez-Martinez, Mª Piedad; Escolar-Reina, Pilar</p> <p>2016-01-01</p> <p>Abstract Identifying those patients who underperform in the 6-minute walk test (6MWT <350 m), and the reasons for their poor performance, is a major concern in the management of chronic obstructive pulmonary disease. To explore the <span class="hlt">accuracy</span> and relevance of the 4-m gait-speed (4MGS) test, and the 5-repetition sit-to-stand (5STS) test, as diagnostic markers, and clinical determinants, of poor performance in the 6MWT. We recruited 137 patients with stable chronic obstructive pulmonary disease to participate in our cross-sectional study. Patients completed the 4MGS and 5STS tests, with quantitative (in seconds) and qualitative ordinal data collected; the latter were categorized using a scale of 0 to 4. The following potential covariates and clinical determinants of poor 6MWT were collated: age, quadriceps muscle-strength (QMS), health status, dyspnea, depression, and airflow limitation. Area under the receiver-operating characteristic curve data (AUC) was used to assess <span class="hlt">accuracy</span>, with logistic regression used to explore relevance as clinical determinants. The AUCs generated using the 4MGS and 5STS tests were comparable, at 0.719 (95% confidence interval [CI] 0.629–0.809) and 0.711 (95% CI 0.613–0.809), respectively. With ordinal data, the 5STS test was most accurate (AUC of 0.732; 95% CI 0.645–0.819); the 4MGS test showed poor discriminatory power (AUC <0.7), although <span class="hlt">accuracy</span> improved (0.726, 95% CI 0.637–0.816) when covariates were included. Unlike the 4MGS test, the 5STS test provided a significant clinical determinant of a poor 6MWT (odds ratio 1.23, 95% CI 1.05–1.44). The 5STS test reliably predicts a poor 6MWT, especially when using ordinal data. Used alone, the 4MGS test is reliable when measured with continuous data. PMID:27583918</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19930030955&hterms=global+positioning+satellites&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dglobal%2Bpositioning%2Bsatellites','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19930030955&hterms=global+positioning+satellites&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3Dglobal%2Bpositioning%2Bsatellites"><span id="translatedtitle"><span class="hlt">Absolute</span> positioning using DORIS tracking of the SPOT-2 satellite</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Watkins, M. M.; Ries, J. C.; Davis, G. W.</p> <p>1992-01-01</p> <p>The ability of the French DORIS system operating on the SPOT-2 satellite to provide <span class="hlt">absolute</span> site positioning at the 20-30-centimeter level using 80 d of data is demonstrated. The <span class="hlt">accuracy</span> of the vertical component is comparable to that of the horizontal components, indicating that residual troposphere error is not a limiting factor. The translation parameters indicate that the DORIS network realizes a geocentric frame to about 50 nm in each component. The considerable amount of data provided by the nearly global, all-weather DORIS network allowed this complex parameterization required to reduce the unmodeled forces acting on the low-earth satellite. Site velocities with <span class="hlt">accuracies</span> better than 10 mm/yr should certainly be possible using the multiyear span of the SPOT series and Topex/Poseidon missions.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/21611785','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/21611785"><span id="translatedtitle"><span class="hlt">Absolute</span> Geodetic Rotation Measurement Using Atom Interferometry</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Stockton, J. K.; Takase, K.; Kasevich, M. A.</p> <p>2011-09-23</p> <p>We demonstrate a cold-atom interferometer gyroscope which overcomes <span class="hlt">accuracy</span> and dynamic range limitations of previous atom interferometer gyroscopes. We show how the instrument can be used for precise determination of latitude, azimuth (true north), and Earth's rotation rate. Spurious noise terms related to multiple-path interferences are suppressed by employing a novel <span class="hlt">time</span>-skewed pulse sequence. Extended versions of this instrument appear capable of meeting the stringent requirements for inertial navigation, geodetic applications of Earth's rotation rate determination, and tests of general relativity.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/18026562','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/18026562"><span id="translatedtitle"><span class="hlt">Absolute</span> Temperature Monitoring Using RF Radiometry in the MRI Scanner.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>El-Sharkawy, Abdel-Monem M; Sotiriadis, Paul P; Bottomley, Paul A; Atalar, Ergin</p> <p>2006-11-01</p> <p>Temperature detection using microwave radiometry has proven value for noninvasively measuring the <span class="hlt">absolute</span> temperature of tissues inside the body. However, current clinical radiometers operate in the gigahertz range, which limits their depth of penetration. We have designed and built a noninvasive radiometer which operates at radio frequencies (64 MHz) with ∼100-kHz bandwidth, using an external RF loop coil as a thermal detector. The core of the radiometer is an accurate impedance measurement and automatic matching circuit of 0.05 Ω <span class="hlt">accuracy</span> to compensate for any load variations. The radiometer permits temperature measurements with <span class="hlt">accuracy</span> of ±0.1°K, over a tested physiological range of 28° C-40° C in saline phantoms whose electric properties match those of tissue. Because 1.5 T magnetic resonance imaging (MRI) scanners also operate at 64 MHz, we demonstrate the feasibility of integrating our radiometer with an MRI scanner to monitor RF power deposition and temperature dosimetry, obtaining coarse, spatially resolved, <span class="hlt">absolute</span> thermal maps in the physiological range. We conclude that RF radiometry offers promise as a direct, noninvasive method of monitoring tissue heating during MRI studies and thereby providing an independent means of verifying patient-safe operation. Other potential applications include titration of hyper- and hypo-therapies. PMID:18026562</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22310860','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22310860"><span id="translatedtitle"><span class="hlt">Absolute</span> analytical prediction of photonic crystal guided mode resonance wavelengths</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Hermannsson, Pétur Gordon; Vannahme, Christoph; Smith, Cameron L. C.; Kristensen, Anders</p> <p>2014-08-18</p> <p>A class of photonic crystal resonant reflectors known as guided mode resonant filters are optical structures that are widely used in the field of refractive index sensing, particularly in biosensing. For the purposes of understanding and design, their behavior has traditionally been modeled numerically with methods such as rigorous coupled wave analysis. Here it is demonstrated how the <span class="hlt">absolute</span> resonance wavelengths of such structures can be predicted by analytically modeling them as slab waveguides in which the propagation constant is determined by a phase matching condition. The model is experimentally verified to be capable of predicting the <span class="hlt">absolute</span> resonance wavelengths to an <span class="hlt">accuracy</span> of within 0.75 nm, as well as resonance wavelength shifts due to changes in cladding index within an <span class="hlt">accuracy</span> of 0.45 nm across the visible wavelength regime in the case where material dispersion is taken into account. Furthermore, it is demonstrated that the model is valid beyond the limit of low grating modulation, for periodically discontinuous waveguide layers, high refractive index contrasts, and highly dispersive media.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4136735','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4136735"><span id="translatedtitle">Relative <span class="hlt">Accuracy</span> Evaluation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhang, Yan; Wang, Hongzhi; Yang, Zhongsheng; Li, Jianzhong</p> <p>2014-01-01</p> <p>The quality of data plays an important role in business analysis and decision making, and data <span class="hlt">accuracy</span> is an important aspect in data quality. Thus one necessary task for data quality management is to evaluate the <span class="hlt">accuracy</span> of the data. And in order to solve the problem that the <span class="hlt">accuracy</span> of the whole data set is low while a useful part may be high, it is also necessary to evaluate the <span class="hlt">accuracy</span> of the query results, called relative <span class="hlt">accuracy</span>. However, as far as we know, neither measure nor effective methods for the <span class="hlt">accuracy</span> evaluation methods are proposed. Motivated by this, for relative <span class="hlt">accuracy</span> evaluation, we propose a systematic method. We design a relative <span class="hlt">accuracy</span> evaluation framework for relational databases based on a new metric to measure the <span class="hlt">accuracy</span> using statistics. We apply the methods to evaluate the precision and recall of basic queries, which show the result's relative <span class="hlt">accuracy</span>. We also propose the method to handle data update and to improve <span class="hlt">accuracy</span> evaluation using functional dependencies. Extensive experimental results show the effectiveness and efficiency of our proposed framework and algorithms. PMID:25133752</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_19");'>19</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li class="active"><span>21</span></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_21 --> <div id="page_22" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="421"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/7900888','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/7900888"><span id="translatedtitle">An ultrasonic system for measurement of <span class="hlt">absolute</span> myocardial thickness using a single transducer.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Pitsillides, K F; Longhurst, J C</p> <p>1995-03-01</p> <p>We have developed an ultrasonic instrument that can measure <span class="hlt">absolute</span> regional myocardial wall motion throughout the cardiac cycle using a single epicardial piezoelectric transducer. The methods in place currently that utilize ultrasound to measure myocardial wall thickness are the transit-<span class="hlt">time</span> sonomicrometer (TTS) and, more recently, the Doppler echo displacement method. Both methods have inherent disadvantages. To address the need for an instrument that can measure <span class="hlt">absolute</span> dimensions of myocardial wall at any depth, an ultrasonic single-crystal sonomicrometer (SCS) system was developed. This system can identify and track the boundary of the endocardial muscle-blood interface. With this instrument, it is possible to obtain, from a single epicardial transducer, measurement of myocardial wall motion that is calibrated in <span class="hlt">absolute</span> dimensional units. The operating principles of the proposed myocardial dimension measurement system are as follows. A short duration ultrasonic burst having a frequency of 10 MHz is transmitted from the piezoelectric transducer. Reflected echoes are sampled at two distinct <span class="hlt">time</span> intervals to generate reference and interface sample volumes. During steady state, the two sample volumes are adjusted so that the reference volume remains entirely within the myocardium, whereas half of the interface sampled volume is located within the myocardium. After amplification and filtering, the true root mean square values of both signals are compared and an error signal is generated. A closed-loop circuit uses the integrated error signal to continuously adjust the position of the two sample volumes. We have compared our system in vitro against a known signal and in vivo against the two-crystal TTS system during control, suppression (ischemia), and enhancement (isoproterenol) of myocardial function. Results were obtained in vitro for <span class="hlt">accuracy</span> (> 99%), signal linearity (r = 0.99), and frequency response to heart rates > 450 beats/min, and in vivo data were</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=20160005178&hterms=Climate&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DClimate','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=20160005178&hterms=Climate&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3DClimate"><span id="translatedtitle">Demonstrating the Error Budget for the Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory Through Solar Irradiance Measurements</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thome, Kurtis; McCorkel, Joel; McAndrew, Brendan</p> <p>2016-01-01</p> <p>The Climate <span class="hlt">Absolute</span> 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 <span class="hlt">accuracy</span> of climate change. A CLARREO objective is to improve the <span class="hlt">accuracy</span> of SI-traceable, <span class="hlt">absolute</span> calibration at infrared and reflected solar wavelengths to reach on-orbit <span class="hlt">accuracies</span> 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 <span class="hlt">Absolute</span> 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. <span class="hlt">Absolute</span> radiometric response is determined using laser-based calibration sources and applied to direct solar views for comparison with accepted solar irradiance models to demonstrate <span class="hlt">accuracy</span> values giving confidence in the error budget for the CLARREO reflectance retrieval.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=stimulus+AND+response+AND+model&pg=7&id=EJ766484','ERIC'); return false;" href="http://eric.ed.gov/?q=stimulus+AND+response+AND+model&pg=7&id=EJ766484"><span id="translatedtitle"><span class="hlt">Absolute</span> Identification Is Relative: A Reply to Brown, Marley, and Lacouture (2007)</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Stewart, Neil</p> <p>2007-01-01</p> <p>N. Stewart, G. D. A. Brown, and N. Chater presented a relative judgment model (RJM) of <span class="hlt">absolute</span> identification, in which the current stimulus is judged relative to the preceding stimulus. S. Brown, A. A. J. Marley, and Y. Lacouture found that the RJM does not predict their finding of increased <span class="hlt">accuracy</span> after large stimulus jumps, except at the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015SPIE.9607E..1CT','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015SPIE.9607E..1CT"><span id="translatedtitle">Demonstrating the error budget for the Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory through solar irradiance measurements</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Thome, Kurtis; McCorkel, Joel; McAndrew, Brendan</p> <p>2015-09-01</p> <p>The Climate <span class="hlt">Absolute</span> 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 <span class="hlt">accuracy</span> of climate change. A CLARREO objective is to improve the <span class="hlt">accuracy</span> of SI-traceable, <span class="hlt">absolute</span> calibration at infrared and reflected solar wavelengths to reach on-orbit <span class="hlt">accuracies</span> 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 <span class="hlt">Absolute</span> 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 testbed 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. <span class="hlt">Absolute</span> radiometric response is determined using laser-based calibration sources and applied to direct solar views for comparison with accepted solar irradiance models to demonstrate <span class="hlt">accuracy</span> values giving confidence in the error budget for the CLARREO reflectance retrieval.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://files.eric.ed.gov/fulltext/EJ1102846.pdf','ERIC'); return false;" href="http://files.eric.ed.gov/fulltext/EJ1102846.pdf"><span id="translatedtitle">The Effect of Using Relative and <span class="hlt">Absolute</span> Criteria to Decide Students' Passing or Failing a Course</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Sayin, Ayfer</p> <p>2016-01-01</p> <p>In the formation education that is carried out within the scope of undergraduate and non-thesis graduate programs within the same university, different criteria are used to evaluate students' success. In this study, classification <span class="hlt">accuracy</span> of letter grades that are generated to evaluate students' success using relative and <span class="hlt">absolute</span> criteria and…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=66684&keyword=Jacobson&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=68463204&CFTOKEN=89801657','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=66684&keyword=Jacobson&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=68463204&CFTOKEN=89801657"><span id="translatedtitle">IMPROVEMENT OF SMVGEAR II ON VECTOR AND SCALAR MACHINES THROUGH <span class="hlt">ABSOLUTE</span> ERROR TOLERANCE CONTROL (R823186)</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The computer speed of SMVGEAR II was improved markedly on scalar and vector machines with relatively little loss in <span class="hlt">accuracy</span>. The improvement was due to a method of frequently recalculating the <span class="hlt">absolute</span> error tolerance instead of keeping it constant for a given set of chemistry. ...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=tungsten&pg=2&id=EJ370999','ERIC'); return false;" href="http://eric.ed.gov/?q=tungsten&pg=2&id=EJ370999"><span id="translatedtitle">Electrical Noise and the Measurement of <span class="hlt">Absolute</span> Temperature, Boltzmann's Constant and Avogadro's Number.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ericson, T. J.</p> <p>1988-01-01</p> <p>Describes an apparatus capable of measuring <span class="hlt">absolute</span> temperatures of a tungsten filament bulb up to normal running temperature and measuring Botzmann's constant to an <span class="hlt">accuracy</span> of a few percent. Shows that electrical noise techniques are convenient to demonstrate how the concept of temperature is related to the micro- and macroscopic world. (CW)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/27140578','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/27140578"><span id="translatedtitle"><span class="hlt">Absolute</span> flatness testing of skip-flat interferometry by matrix analysis in polar coordinates.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Han, Zhi-Gang; Yin, Lu; Chen, Lei; Zhu, Ri-Hong</p> <p>2016-03-20</p> <p>A new method utilizing matrix analysis in polar coordinates has been presented for <span class="hlt">absolute</span> testing of skip-flat interferometry. The retrieval of the <span class="hlt">absolute</span> profile mainly includes three steps: (1) transform the wavefront maps of the two cavity measurements into data in polar coordinates; (2) retrieve the profile of the reflective flat in polar coordinates by matrix analysis; and (3) transform the profile of the reflective flat back into data in Cartesian coordinates and retrieve the profile of the sample. Simulation of synthetic surface data has been provided, showing the capability of the approach to achieve an <span class="hlt">accuracy</span> of the order of 0.01 nm RMS. The <span class="hlt">absolute</span> profile can be retrieved by a set of closed mathematical formulas without polynomial fitting of wavefront maps or the iterative evaluation of an error function, making the new method more efficient for <span class="hlt">absolute</span> testing.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=organic+AND+carbon&pg=5&id=EJ288694','ERIC'); return false;" href="http://eric.ed.gov/?q=organic+AND+carbon&pg=5&id=EJ288694"><span id="translatedtitle">A New Gimmick for Assigning <span class="hlt">Absolute</span> Configuration.</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Ayorinde, F. O.</p> <p>1983-01-01</p> <p>A five-step procedure is provided to help students in making the assignment <span class="hlt">absolute</span> configuration less bothersome. Examples for both single (2-butanol) and multi-chiral carbon (3-chloro-2-butanol) molecules are included. (JN)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=husserl&pg=3&id=EJ118696','ERIC'); return false;" href="http://eric.ed.gov/?q=husserl&pg=3&id=EJ118696"><span id="translatedtitle">The Simplicity Argument and <span class="hlt">Absolute</span> Morality</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Mijuskovic, Ben</p> <p>1975-01-01</p> <p>In this paper the author has maintained that there is a similarity of thought to be found in the writings of Cudworth, Emerson, and Husserl in his investigation of an <span class="hlt">absolute</span> system of morality. (Author/RK)</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2010AGUFM.A43B0203B','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2010AGUFM.A43B0203B"><span id="translatedtitle">On-Orbit <span class="hlt">Absolute</span> Radiance Standard for Future IR Remote Sensing Instruments</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Best, F. A.; Adler, D. P.; Pettersen, C.; Revercomb, H. E.; Gero, P. J.; Taylor, J. K.; Knuteson, R. O.; Perepezko, J. H.</p> <p>2010-12-01</p> <p>Future NASA infrared remote sensing missions, including the climate benchmark CLARREO mission will require better <span class="hlt">absolute</span> measurement <span class="hlt">accuracy</span> than now available, and will most certainly rely on the emerging capability to fly SI traceable standards that provide irrefutable <span class="hlt">absolute</span> measurement <span class="hlt">accuracy</span>. As an example, instrumentation designed to measure spectrally resolved infrared radiances with an <span class="hlt">absolute</span> brightness temperature error of better than 0.1 K will require high-emissivity (>0.999) calibration blackbodies with emissivity uncertainty of better than 0.06%, and <span class="hlt">absolute</span> temperature uncertainties of better than 0.045K (3 sigma). Key elements of an On-Orbit <span class="hlt">Absolute</span> Radiance Standard (OARS) meeting these stringent requirements have been demonstrated in the laboratory at the University of Wisconsin and are undergoing Technology Readiness Level (TRL) advancement under the NASA Instrument Incubator Program (IIP). We present the new technologies that underlie the OARS and the results of laboratory testing that demonstrate the required <span class="hlt">accuracy</span> is being met. The underlying technologies include on-orbit <span class="hlt">absolute</span> temperature calibration using the transient melt signatures of small quantities (<1g) of reference materials (gallium, water, and mercury) imbedded in the blackbody cavity; and on-orbit cavity spectral emissivity measurement using a heated halo. For these emissivity measurements, a carefully baffled heated cylinder is placed in front of a blackbody in the infrared spectrometer system, and the combined radiance of the blackbody and Heated Halo reflection is observed. Knowledge of key temperatures and the viewing geometry allow the blackbody cavity spectral emissivity to be calculated. This work will culminate with an integrated subsystem that can provide on-orbit end-to-end radiometric <span class="hlt">accuracy</span> validation for infrared remote sensing instruments.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19810040393&hterms=schutz&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dschutz','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19810040393&hterms=schutz&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D60%26Ntt%3Dschutz"><span id="translatedtitle">Orbit <span class="hlt">accuracy</span> assessment for Seasat</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Schutz, B. E.; Tapley, B. D.</p> <p>1980-01-01</p> <p>Laser range measurements are used to determine the orbit of Seasat during the period from July 28, 1978, to Aug. 14, 1978, and the influence of the gravity field, atmospheric drag, and solar radiation pressure on the orbit <span class="hlt">accuracy</span> is investigated. It is noted that for the orbits of three-day duration, little distinction can be made between the influence of different atmospheric models. It is found that the special Seasat gravity field PGS-S3 is most consistent with the data for three-day orbits, but an unmodeled systematic effect in radiation pressure is noted. For orbits of 18-day duration, little distinction can be made between the results derived from the PGS gravity fields. It is also found that the geomagnetic field is an influential factor in the atmospheric modeling during this <span class="hlt">time</span> period. Seasat altimeter measurements are used to determine the <span class="hlt">accuracy</span> of the altimeter measurement <span class="hlt">time</span> tag and to evaluate the orbital <span class="hlt">accuracy</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2001ESASP.464..355T','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2001ESASP.464..355T"><span id="translatedtitle">On the <span class="hlt">absolute</span> alignment of GONG images</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Toner, C. G.</p> <p>2001-01-01</p> <p>In order to combine data from the six instruments in the GONG network the alignment of all of the images must be known to a fairly high precision (~0°.1 for GONG Classic and ~0°.01 for GONG+). The relative orientation is obtained using the angular cross-correlation method described by (Toner & Harvey, 1998). To obtain the <span class="hlt">absolute</span> orientation the Project periodically records a day of drift scans, where the image of the Sun is allowed to drift across the CCD repeatedly throughout the day. These data are then analyzed to deduce the direction of Terrestrial East-West as a function of hour angle (i.e., <span class="hlt">time</span>) for that instrument. The transit of Mercury on Nov. 15, 1999, which was recorded by three of the GONG instruments, provided an independent check on the current alignment procedures. Here we present a comparison of the alignment of GONG images as deduced from both drift scans and the Mercury transit for two GONG sites: Tucson (GONG+ camera) and Mauna Loa (GONG Classic camera). The agreement is within ~0°.01 for both cameras, however, the scatter is substantially larger for GONG Classic: ~0°.03 compared to ~0°.01 for GONG+.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15322648','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15322648"><span id="translatedtitle">Effect of packing types on the dimensional <span class="hlt">accuracy</span> of denture base resin cured by the conventional cycle in relation to post-pressing <span class="hlt">times</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Consani, Rafael Leonardo Xediek; Domitti, Saide Sarckis; Mesquita, Marcelo Ferraz; Consani, Simonides</p> <p>2004-01-01</p> <p>This study investigated the dimensional stability of denture bases influenced by packing methods, in relation to post-pressing <span class="hlt">times</span>, in the Clássico acrylic resin which was prepared according to manufacturer recommendations. Forty maxillary wax bases were made and randomly assigned into 2 groups of 20 specimens each according to the conventional and RS system packing methods. In each method, the specimens were subdivided into immediate, 6, 12 and 24 h post-pressing <span class="hlt">times</span>. The dough of the acrylic resin was packed in metallic flasks and processed in a water bath curing cycle at 74 masculine C for 9 h. After cooling at room temperature, the bases were removed from the flasks, finished and fixed on stone casts with instantaneous adhesive. The resin base-stone cast sets were transversally sectioned into 3 sections and the base-stone gap measured at 5 points in each section. The data were submitted to ANOVA and Tukey's test, which showed that the RS system had a smaller base distortion compared to conventional packing, with the exception of the 24-h post-pressing <span class="hlt">time</span>. There was a statistically significant difference between the packing methods only in section C (posterior palatal zone). In the conventional packing method, the immediate and 6 h <span class="hlt">times</span> demonstrated values with no statistically significant difference between them, as well as between the 12 and 24 h post-pressing <span class="hlt">times</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2013ASPC..472..291D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2013ASPC..472..291D"><span id="translatedtitle">PHASES: A Project to Perform <span class="hlt">Absolute</span> Spectrophotometry from Space</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>del Burgo, C.; Vather, D.; Allende Prieto, C.; Murphy, N.</p> <p>2013-04-01</p> <p>This paper presents the current status of the opto-mechanical design of PHASES (Planet Hunting and AsteroSeismology Explorer Spectrophotometer), which is a project to develop a space-borne telescope to obtain <span class="hlt">absolute</span> flux calibrated spectra of bright stars. The science payload is intended to be housed in a micro-satellite launched into a low-earth Sun-synchronous orbit with an inclination to the equator of 98.7° and a local <span class="hlt">time</span> ascending node LTAN of 6:00 AM. PHASES will be able to measure micromagnitude photometric variations due to stellar oscillations/activity and planet/moon transits. It consists of a 20 cm aperture modified Baker telescope feeding two detectors: the tracking detector provides the fine telescope guidance system with a required pointing stability of 0.2″, and the science detector performs spectrophotometry in the wavelength range 370-960 nm with a resolving power between 200 and 900. The spectrograph is designed to provide 1% RMS flux calibrated spectra with signal-to-noise ratios > 100 for stars with V < 10 in short integration <span class="hlt">times</span>. Our strategy to calibrate the system using A type stars is explained. From comparison with model atmospheres it would be possible to determine the stellar angular diameters with an uncertainty of approximately 0.5%. In the case of a star hosting a transiting planet it would be possible to derive its light curve, and then the planet to stellar radius ratio. Bright stars have high precision Hipparcos parallaxes and the expected level of <span class="hlt">accuracy</span> for their fluxes will be propagated to the stellar radii, and more significantly to the planetary radii. The scientific drivers for PHASES give rise to some design challenges, which are particularly related to the opto-mechanics for extreme environmental conditions. The optical design has been developed with the primary goal of avoiding stray light reaching the science detector. Three different proposals for the opto-mechanical design are under investigation.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22036440','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22036440"><span id="translatedtitle">Superheterodyne configuration for two-wavelength interferometry applied to <span class="hlt">absolute</span> distance measurement</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Le Floch, Sebastien; Salvade, Yves; Droz, Nathalie; Mitouassiwou, Rostand; Favre, Patrick</p> <p>2010-02-01</p> <p>We present a new superheterodyne technique for long-distance measurements by two-wavelength interferometry (TWI). While conventional systems use two acousto-optic modulators to generate two different heterodyne frequencies, here the two frequencies result from synchronized sweeps of optical and radio frequencies. A distributed feedback laser source is injected in an intensity modulator that is driven at the half-wave voltage mode. A radio-frequency signal is applied to this intensity modulator to generate two optical sidebands around the optical carrier. This applied radio frequency consists of a digital ramp between 13 and 15 GHz, with 1 ms duration and with an <span class="hlt">accuracy</span> of better than 1 ppm. Simultaneously, the laser source is frequency modulated by a current modulation that is synchronized on the radio-frequency ramp as well as on a triangle waveform. These two frequency-swept optical signals at the output of the modulator illuminate a Michelson interferometer and create two distinct distance-dependent heterodyne frequencies on the photodetector. The superheterodyne signal is then detected and bandpass filtered to retrieve the <span class="hlt">absolute</span> distance measurement. Experiments between 1 and 15 m confirm the validity of this new concept, leading to a distance <span class="hlt">accuracy</span> of {+-} 50 {mu}m for a 1 ms acquisition <span class="hlt">time</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20050028472','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20050028472"><span id="translatedtitle"><span class="hlt">Accuracy</span> of the Cloud Integrating Nephelometer</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Gerber, Hermann E.</p> <p>2004-01-01</p> <p>Potential error sources for measurements with the Cloud Integrating Nephelometer (CIN) are discussed and analyzed, including systematic errors of the measurement approach, flow and particle-trajectory deviations at flight velocity, ice-crystal breakup on probe surfaces, and errors in calibration and developing scaling constants. It is concluded that errors are minimal, and that the <span class="hlt">accuracy</span> of the CIN should be close to the systematic behavior of the CIN derived in Gerber et al (2000). <span class="hlt">Absolute</span> calibration of the CIN with a transmissometer operating co-located in a mountain-top cloud shows that the earlier scaling constant for the optical extinction coefficient obtained by other means is within 5% of the <span class="hlt">absolute</span> calibration value, and that the CIN measurements on the Citation aircraft flights during the CRYSTAL-FACE study are accurate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22981579','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22981579"><span id="translatedtitle">Bayesian estimation of the diagnostic <span class="hlt">accuracy</span> of a multiplex real-<span class="hlt">time</span> PCR assay and bacteriological culture for 4 common bovine intramammary pathogens.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Paradis, M-È; Haine, D; Gillespie, B; Oliver, S P; Messier, S; Comeau, J; Scholl, D T</p> <p>2012-11-01</p> <p>Bacteriological culture (BC) is the traditional method for intramammary infection diagnosis but lacks sensitivity and is <span class="hlt">time</span> consuming. Multiplex real-<span class="hlt">time</span> PCR (mr-PCR) enables testing the presence of several bacteria and reduces diagnosis <span class="hlt">time</span>. Our objective was to estimate bacterial species-specific sensitivity (Se) and specificity of both BC and mr-PCR tests for detecting bacteria in milk samples from clinical mastitis cases and from apparently normal quarters, using a Bayesian latent class model. Milk samples from 1,014 clinical mastitis cases and 1,495 samples from apparently normal quarters were analyzed by BC and mr-PCR. Two positive culture definitions were used: ≥1 cfu/0.01 mL and ≥10 cfu/0.01 mL of the specified bacteria. The mr-PCR was designed to simultaneously detect Staphylococcus aureus, Streptococcus uberis, Escherichia coli, and Streptococcus agalactiae. The priors used in our Bayesian model were weakly informative, with BC priors using the best available error data. Results were compared with those obtained using uniform priors for mr-PCR to test robustness. Weak and uniform priors gave about the same posterior distributions except for Strep. uberis from normal quarters and Strep. agalactiae. Multiplex real-<span class="hlt">time</span> PCR Se on milk from clinical mastitis were lower than mr-PCR Se on milk from normal quarters. Multiplex real-<span class="hlt">time</span> PCR Se was higher than BC on milk from normal quarters. Multiplex real-<span class="hlt">time</span> PCR Se was generally lower than BC on milk from clinical mastitis and it varied by clinical severity. The estimate specificities of detection for all pathogens were ≥99%, regardless of sample type. The effect of milk sample preservation before testing was evaluated and may have been a factor that affected our observed results. A significant association was observed between sample age and mr-PCR results leading to reduced detection of E. coli and Strep. agalactiae in nonclinical samples. Differences in sample age between conduct of BC and of mr</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19940024091&hterms=beers+law&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbeers%2Blaw','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19940024091&hterms=beers+law&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D30%26Ntt%3Dbeers%2Blaw"><span id="translatedtitle"><span class="hlt">Absolute</span> determination of local tropospheric OH concentrations</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Armerding, Wolfgang; Comes, Franz-Josef</p> <p>1994-01-01</p> <p>Long path absorption (LPA) according to Lambert Beer's law is a method to determine <span class="hlt">absolute</span> concentrations of trace gases such as tropospheric OH. We have developed a LPA instrument which is based on a rapid tuning of the light source which is a frequency doubled dye laser. The laser is tuned across two or three OH absorption features around 308 nm with a scanning speed of 0.07 cm(exp -1)/microsecond and a repetition rate of 1.3 kHz. This high scanning speed greatly reduces the fluctuation of the light intensity caused by the atmosphere. To obtain the required high sensitivity the laser output power is additionally made constant and stabilized by an electro-optical modulator. The present sensitivity is of the order of a few <span class="hlt">times</span> 10(exp 5) OH per cm(exp 3) for an acquisition <span class="hlt">time</span> of a minute and an absorption path length of only 1200 meters so that a folding of the optical path in a multireflection cell was possible leading to a lateral dimension of the cell of a few meters. This allows local measurements to be made. Tropospheric measurements have been carried out in 1991 resulting in the determination of OH diurnal variation at specific days in late summer. Comparison with model calculations have been made. Interferences are mainly due to SO2 absorption. The problem of OH self generation in the multireflection cell is of minor extent. This could be shown by using different experimental methods. The minimum-maximum signal to noise ratio is about 8 x 10(exp -4) for a single scan. Due to the small size of the absorption cell the realization of an open air laboratory is possible in which by use of an additional UV light source or by additional fluxes of trace gases the chemistry can be changed under controlled conditions allowing kinetic studies of tropospheric photochemistry to be made in open air.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20070038225','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20070038225"><span id="translatedtitle">Geolocation <span class="hlt">Accuracy</span> Evaluations of OrbView-3, EROS-A, and SPOT-5 Imagery</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Bresnahan, Paul</p> <p>2007-01-01</p> <p>This viewgraph presentation evaluates <span class="hlt">absolute</span> geolocation <span class="hlt">accuracy</span> of OrbView-3, EROS-A, and SPOT-5 by comparing test imagery-derived ground coordinates to Ground Control Points using SOCET set photogrammetric software.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_20");'>20</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li class="active"><span>22</span></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_22 --> <div id="page_23" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="441"> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/19831037','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/19831037"><span id="translatedtitle">Jasminum flexile flower <span class="hlt">absolute</span> from India--a detailed comparison with three other jasmine <span class="hlt">absolutes</span>.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Braun, Norbert A; Kohlenberg, Birgit; Sim, Sherina; Meier, Manfred; Hammerschmidt, Franz-Josef</p> <p>2009-09-01</p> <p>Jasminum flexile flower <span class="hlt">absolute</span> from the south of India and the corresponding vacuum headspace (VHS) sample of the <span class="hlt">absolute</span> were analyzed using GC and GC-MS. Three other commercially available Indian jasmine <span class="hlt">absolutes</span> from the species: J. sambac, J. officinale subsp. grandiflorum, and J. auriculatum and the respective VHS samples were used for comparison purposes. One hundred and twenty-one compounds were characterized in J. flexile flower <span class="hlt">absolute</span>, with methyl linolate, benzyl salicylate, benzyl benzoate, (2E,6E)-farnesol, and benzyl acetate as the main constituents. A detailed olfactory evaluation was also performed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1025472','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1025472"><span id="translatedtitle">Comparison of diagnostic <span class="hlt">accuracy</span>, <span class="hlt">time</span> dependency, and prognostic impact of abnormal Q waves, combined electrocardiographic criteria, and ST segment abnormalities in right ventricular infarction.</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zehender, M; Kasper, W; Kauder, E; Schönthaler, M; Olschewski, M; Just, H</p> <p>1994-01-01</p> <p>OBJECTIVE--To determine the diagnostic and prognostic impact of abnormal Q waves in comparison to or in combination with ST segment abnormalities in the right precordial and inferior leads as indicators of right ventricular infarction during the acute phase of inferior myocardial infarction. DESIGN--Prospective study of a consecutive series of 200 patients with acute inferior myocardial infarction with and without right ventricular infarction. SETTING--Department of internal medicine, university clinic. RESULTS--Right ventricular infarction was diagnosed in 106 (57%) out of 187 patients from the results of coronary angiography, technetium pyrophosphate scanning, and measurement of haemodynamic variables or at necropsy, or both. In the acute phase of inferior infarction ST segment elevation > or = 0.1 mV in any of the right precordial leads V4-6R was the most reliable criterion for right ventricular infarction (sensitivity, 89%; specificity, 83%). Abnormal Q waves in the right precordial leads, the most specific criterion (91%) for right ventricular infarction, were superior to ST segment elevation in patients admitted > 12 hours after the onset of symptoms. Both ST segment elevation in leads V4-6R (increase in in hospital mortality, 6.2-<span class="hlt">times</span>; P < 0.001; major complications, 2.3-<span class="hlt">times</span>; P < 0.01) and abnormal Q waves (2.3-<span class="hlt">times</span>, P < 0.05; 1.8-<span class="hlt">times</span>, P < 0.05) on admission were highly predictive of a worse outcome during the in hospital period. In the presence of inferior myocardial infarction previously proposed combined electrocardiographic criteria were not better diagnostically or prognostically than ST segment abnormalities and abnormal Q waves alone. CONCLUSIONS--During the first 24 hours of inferior myocardial infarction ST segment elevation and abnormal Q waves derived from the right precordial leads are complementary rather than competitive criteria for reliably diagnosing right ventricular infarction, both indicating a worse in hospital course for the</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19910023392','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19910023392"><span id="translatedtitle">The effect of the Earth's oblate spheroid shape on the <span class="hlt">accuracy</span> of a <span class="hlt">time</span>-of-arrival lightning ground strike locating system</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Casper, Paul W.; Bent, Rodney B.</p> <p>1991-01-01</p> <p>The algorithm used in previous technology <span class="hlt">time</span>-of-arrival lightning mapping systems was based on the assumption that the earth is a perfect spheroid. These systems yield highly-accurate lightning locations, which is their major strength. However, extensive analysis of tower strike data has revealed occasionally significant (one to two kilometer) systematic offset errors which are not explained by the usual error sources. It was determined that these systematic errors reduce dramatically (in some cases) when the oblate shape of the earth is taken into account. The oblate spheroid correction algorithm and a case example is presented.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/22346660','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/22346660"><span id="translatedtitle"><span class="hlt">Absolute</span> radiometric calibration of Als intensity data: effects on <span class="hlt">accuracy</span> and target classification.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kaasalainen, Sanna; Pyysalo, Ulla; Krooks, Anssi; Vain, Ants; Kukko, Antero; Hyyppä, Juha; Kaasalainen, Mikko</p> <p>2011-01-01</p> <p>Radiometric calibration of airborne laser scanning (ALS) intensity data aims at retrieving a value related to the target scattering properties, which is independent on the instrument or flight parameters. The aim of a calibration procedure is also to be able to compare results from different flights and instruments, but practical applications are sparsely available, and the performance of calibration methods for this purpose needs to be further assessed. We have studied the radiometric calibration with data from three separate flights and two different instruments using external calibration targets. We find that the intensity data from different flights and instruments can be compared to each other only after a radiometric calibration process using separate calibration targets carefully selected for each flight. The calibration is also necessary for target classification purposes, such as separating vegetation from sand using intensity data from different flights. The classification results are meaningful only for calibrated intensity data.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/22346660','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/22346660"><span id="translatedtitle"><span class="hlt">Absolute</span> radiometric calibration of Als intensity data: effects on <span class="hlt">accuracy</span> and target classification.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kaasalainen, Sanna; Pyysalo, Ulla; Krooks, Anssi; Vain, Ants; Kukko, Antero; Hyyppä, Juha; Kaasalainen, Mikko</p> <p>2011-01-01</p> <p>Radiometric calibration of airborne laser scanning (ALS) intensity data aims at retrieving a value related to the target scattering properties, which is independent on the instrument or flight parameters. The aim of a calibration procedure is also to be able to compare results from different flights and instruments, but practical applications are sparsely available, and the performance of calibration methods for this purpose needs to be further assessed. We have studied the radiometric calibration with data from three separate flights and two different instruments using external calibration targets. We find that the intensity data from different flights and instruments can be compared to each other only after a radiometric calibration process using separate calibration targets carefully selected for each flight. The calibration is also necessary for target classification purposes, such as separating vegetation from sand using intensity data from different flights. The classification results are meaningful only for calibrated intensity data. PMID:22346660</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016ufm..conf..509K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016ufm..conf..509K"><span id="translatedtitle">Universal Cosmic <span class="hlt">Absolute</span> and Modern Science</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kostro, Ludwik</p> <p></p> <p>The official Sciences, especially all natural sciences, respect in their researches the principle of methodic naturalism i.e. they consider all phenomena as entirely natural and therefore in their scientific explanations they do never adduce or cite supernatural entities and forces. The purpose of this paper is to show that Modern Science has its own self-existent, self-acting, and self-sufficient Natural All-in Being or Omni-Being i.e. the entire Nature as a Whole that justifies the scientific methodic naturalism. Since this Natural All-in Being is one and only It should be considered as the own scientifically justified Natural <span class="hlt">Absolute</span> of Science and should be called, in my opinion, the Universal Cosmic <span class="hlt">Absolute</span> of Modern Science. It will be also shown that the Universal Cosmic <span class="hlt">Absolute</span> is ontologically enormously stratified and is in its ultimate i.e. in its most fundamental stratum trans-reistic and trans-personal. It means that in its basic stratum. It is neither a Thing or a Person although It contains in Itself all things and persons with all other sentient and conscious individuals as well, On the turn of the 20th century the Science has begun to look for a theory of everything, for a final theory, for a master theory. In my opinion the natural Universal Cosmic <span class="hlt">Absolute</span> will constitute in such a theory the radical all penetrating Ultimate Basic Reality and will substitute step by step the traditional supernatural personal <span class="hlt">Absolute</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1482457','PMC'); return false;" href="http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1482457"><span id="translatedtitle">Low <span class="hlt">accuracy</span> and low consistency of fourth-graders' school breakfast and school lunch recalls</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>THOMPSON, WILLIAM 0.; LITAKER, MARK S.; FRYE, FRANCESCA H.A.; GUINN, CAROLINE H.</p> <p>2005-01-01</p> <p>Objective To determine the <span class="hlt">accuracy</span> and consistency of fourth-graders' school breakfast and school lunch recalls obtained during 24-hour recalls and compared with observed intake. Design Children were interviewed using a multiple-pass protocol at school the morning after being observed eating school breakfast and school lunch. Subjects 104 children stratified by ethnicity (African-American, white) and gender were randomly selected and interviewed up to 3 <span class="hlt">times</span> each with 4 to 14 weeks between each interview. Statistical analysis Match, omission, and intrusion rates to determine <span class="hlt">accuracy</span> of reporting items; arithmetic and/or <span class="hlt">absolute</span> differences to determine <span class="hlt">accuracy</span> for reporting amounts; total inaccuracy to determine inaccuracy for reporting items and amounts combined; intraclass correlation coefficients (ICC) to determine consistency. Results Means were 51% for omission rate, 39% for intrusion rate, and 7.1 servings for total inaccuracy. Total inaccuracy decreased significantly from the first to the third recall (P=0.006). The ICC was 0.29 for total inaccuracy and 0.15 for omission rate. For all meal components except bread/grain and beverage, there were more omissions than intrusions. Mean arithmetic and <span class="hlt">absolute</span> differences per serving in amount reported for matches were -0.08 and 0.24, respectively. Mean amounts per serving of omissions and intrusions were 0.86 and 0.80, respectively. Applications/conclusions The low <span class="hlt">accuracy</span> and low consistency of children's recalls from this study raise concerns regarding the current uses of dietary recalls obtained from children. To improve the <span class="hlt">accuracy</span> and consistency of children's dietary recalls, validation studies are needed to determine the best way(s) to interview children. PMID:11905461</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20030003723','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20030003723"><span id="translatedtitle">Towards Arbitrary <span class="hlt">Accuracy</span> Inviscid Surface Boundary Conditions</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Dyson, Rodger W.; Hixon, Ray</p> <p>2002-01-01</p> <p>Inviscid nonlinear surface boundary conditions are currently limited to third order <span class="hlt">accuracy</span> in <span class="hlt">time</span> for non-moving surfaces and actually reduce to first order in <span class="hlt">time</span> when the surfaces move. For steady-state calculations it may be possible to achieve higher <span class="hlt">accuracy</span> in space, but high <span class="hlt">accuracy</span> in <span class="hlt">time</span> is required for efficient simulation of multiscale unsteady phenomena. A surprisingly simple technique is shown here that can be used to correct the normal pressure derivatives of the flow at a surface on a Cartesian grid so that arbitrarily high order <span class="hlt">time</span> <span class="hlt">accuracy</span> is achieved in idealized cases. This work demonstrates that nonlinear high order <span class="hlt">time</span> <span class="hlt">accuracy</span> at a solid surface is possible and desirable, but it also shows that the current practice of only correcting the pressure is inadequate.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015PhRvA..92f2125A','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015PhRvA..92f2125A"><span id="translatedtitle">Quantum theory allows for <span class="hlt">absolute</span> maximal contextuality</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Amaral, Barbara; Cunha, Marcelo Terra; Cabello, Adán</p> <p>2015-12-01</p> <p>Contextuality is a fundamental feature of quantum theory and a necessary resource for quantum computation and communication. It is therefore important to investigate how large contextuality can be in quantum theory. Linear contextuality witnesses can be expressed as a sum S of n probabilities, and the independence number α and the Tsirelson-like number ϑ of the corresponding exclusivity graph are, respectively, the maximum of S for noncontextual theories and for the theory under consideration. A theory allows for <span class="hlt">absolute</span> maximal contextuality if it has scenarios in which ϑ /α approaches n . Here we show that quantum theory allows for <span class="hlt">absolute</span> maximal contextuality despite what is suggested by the examination of the quantum violations of Bell and noncontextuality inequalities considered in the past. Our proof is not constructive and does not single out explicit scenarios. Nevertheless, we identify scenarios in which quantum theory allows for almost-<span class="hlt">absolute</span>-maximal contextuality.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/6063303','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/6063303"><span id="translatedtitle"><span class="hlt">Absolute</span> calibration in vivo measurement systems</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Kruchten, D.A.; Hickman, D.P.</p> <p>1991-02-01</p> <p>Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining <span class="hlt">absolute</span> calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. <span class="hlt">Absolute</span> calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The <span class="hlt">absolute</span> calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24117660','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24117660"><span id="translatedtitle">Quantitative standards for <span class="hlt">absolute</span> linguistic universals.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Piantadosi, Steven T; Gibson, Edward</p> <p>2014-01-01</p> <p><span class="hlt">Absolute</span> linguistic universals are often justified by cross-linguistic analysis: If all observed languages exhibit a property, the property is taken to be a likely universal, perhaps specified in the cognitive or linguistic systems of language learners and users. In many cases, these patterns are then taken to motivate linguistic theory. Here, we show that cross-linguistic analysis will very rarely be able to statistically justify <span class="hlt">absolute</span>, inviolable patterns in language. We formalize two statistical methods--frequentist and Bayesian--and show that in both it is possible to find strict linguistic universals, but that the numbers of independent languages necessary to do so is generally unachievable. This suggests that methods other than typological statistics are necessary to establish <span class="hlt">absolute</span> properties of human language, and thus that many of the purported universals in linguistics have not received sufficient empirical justification.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/servlets/purl/371207','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/servlets/purl/371207"><span id="translatedtitle">Molecular iodine <span class="hlt">absolute</span> frequencies. Final report</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Sansonetti, C.J.</p> <p>1990-06-25</p> <p>Fifty specified lines of {sup 127}I{sub 2} were studied by Doppler-free frequency modulation spectroscopy. For each line the classification of the molecular transition was determined, hyperfine components were identified, and one well-resolved component was selected for precise determination of its <span class="hlt">absolute</span> frequency. In 3 cases, a nearby alternate line was selected for measurement because no well-resolved component was found for the specified line. <span class="hlt">Absolute</span> frequency determinations were made with an estimated uncertainty of 1.1 MHz by locking a dye laser to the selected hyperfine component and measuring its wave number with a high-precision Fabry-Perot wavemeter. For each line results of the <span class="hlt">absolute</span> measurement, the line classification, and a Doppler-free spectrum are given.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27586721','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27586721"><span id="translatedtitle"><span class="hlt">Absolute</span> pitch in Costa Rica: Distribution of pitch identification ability and implications for its genetic basis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Chavarria-Soley, Gabriela</p> <p>2016-08-01</p> <p><span class="hlt">Absolute</span> pitch is the unusual ability to recognize a pitch without an external reference. The current view is that both environmental and genetic factors are involved in the acquisition of the trait. In the present study, 127 adult musicians were subjected to a musical tone identification test. Subjects were university music students and volunteers who responded to a newspaper article. The test consisted of the identification of 40 piano and 40 pure tones. Subjects were classified in three categories according to their pitch naming ability: <span class="hlt">absolute</span> pitch (AP), high <span class="hlt">accuracy</span> of tone identification (HA), and non-<span class="hlt">absolute</span> pitch (non-AP). Both the percentage of correct responses and the mean <span class="hlt">absolute</span> deviation showed a statistically significant variation between categories. A very clear pattern of higher <span class="hlt">accuracy</span> for white than for black key notes was observed for the HA and the non-AP groups. Meanwhile, the AP group had an almost perfect pitch naming <span class="hlt">accuracy</span> for both kinds of tones. Each category presented a very different pattern of deviation around the correct response. The age at the beginning of musical training did not differ between categories. The distribution of pitch identification ability in this study suggests a complex inheritance of the trait. PMID:27586721</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20140001056','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20140001056"><span id="translatedtitle">Evaluation of the <span class="hlt">Absolute</span> Regional Temperature Potential</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Shindell, D. T.</p> <p>2012-01-01</p> <p>The <span class="hlt">Absolute</span> Regional Temperature Potential (ARTP) is one of the few climate metrics that provides estimates of impacts at a sub-global scale. The ARTP presented here gives the <span class="hlt">time</span>-dependent temperature response in four latitude bands (90-28degS, 28degS-28degN, 28-60degN and 60-90degN) as a function of emissions based on the forcing in those bands caused by the emissions. It is based on a large set of simulations performed with a single atmosphere-ocean climate model to derive regional forcing/response relationships. Here I evaluate the robustness of those relationships using the forcing/response portion of the ARTP to estimate regional temperature responses to the historic aerosol forcing in three independent climate models. These ARTP results are in good accord with the actual responses in those models. Nearly all ARTP estimates fall within +/-20%of the actual responses, though there are some exceptions for 90-28degS and the Arctic, and in the latter the ARTP may vary with forcing agent. However, for the tropics and the Northern Hemisphere mid-latitudes in particular, the +/-20% range appears to be roughly consistent with the 95% confidence interval. Land areas within these two bands respond 39-45% and 9-39% more than the latitude band as a whole. The ARTP, presented here in a slightly revised form, thus appears to provide a relatively robust estimate for the responses of large-scale latitude bands and land areas within those bands to inhomogeneous radiative forcing and thus potentially to emissions as well. Hence this metric could allow rapid evaluation of the effects of emissions policies at a finer scale than global metrics without requiring use of a full climate model.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120012063','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120012063"><span id="translatedtitle">Orion <span class="hlt">Absolute</span> Navigation System Progress and Challenge</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Holt, Greg N.; D'Souza, Christopher</p> <p>2012-01-01</p> <p>The <span class="hlt">absolute</span> navigation design of NASA's Orion vehicle is described. It has undergone several iterations and modifications since its inception, and continues as a work-in-progress. This paper seeks to benchmark the current state of the design and some of the rationale and analysis behind it. There are specific challenges to address when preparing a <span class="hlt">timely</span> and effective design for the Exploration Flight Test (EFT-1), while still looking ahead and providing software extensibility for future exploration missions. The primary onboard measurements in a Near-Earth or Mid-Earth environment consist of GPS pseudo-range and delta-range, but for future explorations missions the use of star-tracker and optical navigation sources need to be considered. Discussions are presented for state size and composition, processing techniques, and consider states. A presentation is given for the processing technique using the computationally stable and robust UDU formulation with an Agee-Turner Rank-One update. This allows for computational savings when dealing with many parameters which are modeled as slowly varying Gauss-Markov processes. Preliminary analysis shows up to a 50% reduction in computation versus a more traditional formulation. Several state elements are discussed and evaluated, including position, velocity, attitude, clock bias/drift, and GPS measurement biases in addition to bias, scale factor, misalignment, and non-orthogonalities of the accelerometers and gyroscopes. Another consideration is the initialization of the EKF in various scenarios. Scenarios such as single-event upset, ground command, and cold start are discussed as are strategies for whole and partial state updates as well as covariance considerations. Strategies are given for dealing with latent measurements and high-rate propagation using multi-rate architecture. The details of the rate groups and the data ow between the elements is discussed and evaluated.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4013095','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4013095"><span id="translatedtitle">Updates in the real-<span class="hlt">time</span> Dose Tracking System (DTS) to improve the <span class="hlt">accuracy</span> in calculating the radiation dose to the patients skin during fluoroscopic procedures</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Rana, Vijay K.; Rudin, Stephen; Bednarek, Daniel R.</p> <p>2013-01-01</p> <p>We have developed a dose-tracking system (DTS) to manage the risk of deterministic skin effects to the patient during fluoroscopic image-guided interventional cardiac procedures. The DTS calculates the radiation dose to the patient’s skin in real-<span class="hlt">time</span> by acquiring exposure parameters and imaging-system geometry from the digital bus on a Toshiba C-arm unit and displays the cumulative dose values as a color map on a 3D graphic of the patient for immediate feedback to the interventionalist. Several recent updates have been made to the software to improve its function and performance. Whereas the older system needed manual input of pulse rate for dose-rate calculation and used the CPU clock with its potential latency to monitor exposure duration, each x-ray pulse is now individually processed to determine the skin-dose increment and to automatically measure the pulse rate. We also added a correction for the table pad which was found to reduce the beam intensity to the patient for under-table projections by an additional 5–12% over that of the table alone at 80 kVp for the x-ray filters on the Toshiba system. Furthermore, mismatch between the DTS graphic and the patient skin can result in inaccuracies in dose calculation because of inaccurate inverse-square-distance calculation. Therefore, a means for quantitative adjustment of the patient-graphic-model position and a parameterized patient-graphic library have been developed to allow the graphic to more closely match the patient. These changes provide more accurate estimation of the skin-dose which is critical for managing patient radiation risk. PMID:24817801</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/24817801','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/24817801"><span id="translatedtitle">Updates in the real-<span class="hlt">time</span> Dose Tracking System (DTS) to improve the <span class="hlt">accuracy</span> in calculating the radiation dose to the patients skin during fluoroscopic procedures.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Rana, Vijay K; Rudin, Stephen; Bednarek, Daniel R</p> <p>2013-03-01</p> <p>We have developed a dose-tracking system (DTS) to manage the risk of deterministic skin effects to the patient during fluoroscopic image-guided interventional cardiac procedures. The DTS calculates the radiation dose to the patient's skin in real-<span class="hlt">time</span> by acquiring exposure parameters and imaging-system geometry from the digital bus on a Toshiba C-arm unit and displays the cumulative dose values as a color map on a 3D graphic of the patient for immediate feedback to the interventionalist. Several recent updates have been made to the software to improve its function and performance. Whereas the older system needed manual input of pulse rate for dose-rate calculation and used the CPU clock with its potential latency to monitor exposure duration, each x-ray pulse is now individually processed to determine the skin-dose increment and to automatically measure the pulse rate. We also added a correction for the table pad which was found to reduce the beam intensity to the patient for under-table projections by an additional 5-12% over that of the table alone at 80 kVp for the x-ray filters on the Toshiba system. Furthermore, mismatch between the DTS graphic and the patient skin can result in inaccuracies in dose calculation because of inaccurate inverse-square-distance calculation. Therefore, a means for quantitative adjustment of the patient-graphic-model position and a parameterized patient-graphic library have been developed to allow the graphic to more closely match the patient. These changes provide more accurate estimation of the skin-dose which is critical for managing patient radiation risk.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/23832375','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/23832375"><span id="translatedtitle">Ascertainment of medicaid payment for delivery on the iowa birth certificate: is <span class="hlt">accuracy</span> sufficient for <span class="hlt">timely</span> policy and program relevant analysis?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kane, Debra J; Sappenfield, William M</p> <p>2014-05-01</p> <p>The Iowa Department of Public Health annually links Medicaid claims data to the birth certificate. Because the latest version of the birth certificate provides more <span class="hlt">timely</span> and less costly information on delivery payment source, we were interested in assessing the validity and reliability of the birth certificate payment source compared to Medicaid paid claims. We linked Medicaid paid claims to birth certificates for calendar years 2007-2009 (n = 120,626). We measured reliability by Kappa statistic and validity by sensitivity, specificity, predictive value positive and negative. We examined reliability and validity overall and by maternal characteristics (e.g. age, race, ethnicity, education). The Kappa statistic for the birth certificate payment source indicated substantial agreement (0.78; 95 % CL 0.78-0.79). Sensitivity and specificity were also high, 86.3 % (95 % CL 86.0-86 6 %) and 91.9 % (95 % CL 91.7-92.1 %), respectively. The predictive value positive was 87.0 %. The predictive value negative was 91.4 %. Kappa and specificity were lower among women of racial and ethnic minorities, women younger than age 24, and women with less education. The overall Kappa, sensitivity and specificity generally suggest the birth certificate payment source is as valid and reliable as the linked data source. The birth certificate payment source is less valid and reliable for women of racial and ethnic minorities, women younger than age 24, and those with less education. Consequently caution should be exercised when using the birth certificate payment source for monitoring service use by the Medicaid population within specific population subgroups.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4922566','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4922566"><span id="translatedtitle"><span class="hlt">Absolute</span> Cerebral Blood Flow Infarction Threshold for 3-Hour Ischemia <span class="hlt">Time</span> Determined with CT Perfusion and 18F-FFMZ-PET Imaging in a Porcine Model of Cerebral Ischemia</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Cockburn, Neil; Kovacs, Michael</p> <p>2016-01-01</p> <p>CT Perfusion (CTP) derived cerebral blood flow (CBF) thresholds have been proposed as the optimal parameter for distinguishing the infarct core prior to reperfusion. Previous threshold-derivation studies have been limited by uncertainties introduced by infarct expansion between the acute phase of stroke and follow-up imaging, or DWI lesion reversibility. In this study a model is proposed for determining infarction CBF thresholds at 3hr ischemia <span class="hlt">time</span> by comparing contemporaneously acquired CTP derived CBF maps to 18F-FFMZ-PET imaging, with the objective of deriving a CBF threshold for infarction after 3 hours of ischemia. Endothelin-1 (ET-1) was injected into the brain of Duroc-Cross pigs (n = 11) through a burr hole in the skull. CTP images were acquired 10 and 30 minutes post ET-1 injection and then every 30 minutes for 150 minutes. 370 MBq of 18F-FFMZ was injected ~120 minutes post ET-1 injection and PET images were acquired for 25 minutes starting ~155–180 minutes post ET-1 injection. CBF maps from each CTP acquisition were co-registered and converted into a median CBF map. The median CBF map was co-registered to blood volume maps for vessel exclusion, an average CT image for grey/white matter segmentation, and 18F-FFMZ-PET images for infarct delineation. Logistic regression and ROC analysis were performed on infarcted and non-infarcted pixel CBF values for each animal that developed infarct. Six of the eleven animals developed infarction. The mean CBF value corresponding to the optimal operating point of the ROC curves for the 6 animals was 12.6 ± 2.8 mL·min-1·100g-1 for infarction after 3 hours of ischemia. The porcine ET-1 model of cerebral ischemia is easier to implement then other large animal models of stroke, and performs similarly as long as CBF is monitored using CTP to prevent reperfusion. PMID:27347877</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/27347877','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/27347877"><span id="translatedtitle"><span class="hlt">Absolute</span> Cerebral Blood Flow Infarction Threshold for 3-Hour Ischemia <span class="hlt">Time</span> Determined with CT Perfusion and 18F-FFMZ-PET Imaging in a Porcine Model of Cerebral Ischemia.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Wright, Eric A; d'Esterre, Christopher D; Morrison, Laura B; Cockburn, Neil; Kovacs, Michael; Lee, Ting-Yim</p> <p>2016-01-01</p> <p>CT Perfusion (CTP) derived cerebral blood flow (CBF) thresholds have been proposed as the optimal parameter for distinguishing the infarct core prior to reperfusion. Previous threshold-derivation studies have been limited by uncertainties introduced by infarct expansion between the acute phase of stroke and follow-up imaging, or DWI lesion reversibility. In this study a model is proposed for determining infarction CBF thresholds at 3hr ischemia <span class="hlt">time</span> by comparing contemporaneously acquired CTP derived CBF maps to 18F-FFMZ-PET imaging, with the objective of deriving a CBF threshold for infarction after 3 hours of ischemia. Endothelin-1 (ET-1) was injected into the brain of Duroc-Cross pigs (n = 11) through a burr hole in the skull. CTP images were acquired 10 and 30 minutes post ET-1 injection and then every 30 minutes for 150 minutes. 370 MBq of 18F-FFMZ was injected ~120 minutes post ET-1 injection and PET images were acquired for 25 minutes starting ~155-180 minutes post ET-1 injection. CBF maps from each CTP acquisition were co-registered and converted into a median CBF map. The median CBF map was co-registered to blood volume maps for vessel exclusion, an average CT image for grey/white matter segmentation, and 18F-FFMZ-PET images for infarct delineation. Logistic regression and ROC analysis were performed on infarcted and non-infarcted pixel CBF values for each animal that developed infarct. Six of the eleven animals developed infarction. The mean CBF value corresponding to the optimal operating point of the ROC curves for the 6 animals was 12.6 ± 2.8 mL·min-1·100g-1 for infarction after 3 hours of ischemia. The porcine ET-1 model of cerebral ischemia is easier to implement then other large animal models of stroke, and performs similarly as long as CBF is monitored using CTP to prevent reperfusion. PMID:27347877</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li class="active"><span>23</span></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_23 --> <div id="page_24" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="461"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://pubs.er.usgs.gov/publication/70026377','USGSPUBS'); return false;" href="http://pubs.er.usgs.gov/publication/70026377"><span id="translatedtitle">Landsat-5 TM reflective-band <span class="hlt">absolute</span> radiometric calibration</span></a></p> <p><a target="_blank" href="http://pubs.er.usgs.gov/pubs/index.jsp?view=adv">USGS Publications Warehouse</a></p> <p>Chander, G.; Helder, D.L.; Markham, B.L.; Dewald, J.D.; Kaita, E.; Thome, K.J.; Micijevic, E.; Ruggles, T.A.</p> <p>2004-01-01</p> <p>The Landsat-5 Thematic Mapper (TM) sensor provides the longest running continuous dataset of moderate spatial resolution remote sensing imagery, dating back to its launch in March 1984. Historically, the radiometric calibration procedure for this imagery used the instrument's response to the Internal Calibrator (IC) on a scene-by-scene basis to determine the gain and offset of each detector. Due to observed degradations in the IC, a new procedure was implemented for U.S.-processed data in May 2003. This new calibration procedure is based on a lifetime radiometric calibration model for the instrument's reflective bands (1-5 and 7) and is derived, in part, from the IC response without the related degradation effects and is tied to the cross calibration with the Landsat-7 Enhanced Thematic Mapper Plus. Reflective-band <span class="hlt">absolute</span> radiometric <span class="hlt">accuracy</span> of the instrument tends to be on the order of 7% to 10%, based on a variety of calibration methods.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26880597','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26880597"><span id="translatedtitle">Assignment of <span class="hlt">absolute</span> stereostructures through quantum mechanics electronic and vibrational circular dichroism calculations.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Dai, Peng; Jiang, Nan; Tan, Ren-Xiang</p> <p>2016-01-01</p> <p>Elucidation of <span class="hlt">absolute</span> configuration of chiral molecules including structurally complex natural products remains a challenging problem in organic chemistry. A reliable method for assigning the <span class="hlt">absolute</span> stereostructure is to combine the experimental circular dichroism (CD) techniques such as electronic and vibrational CD (ECD and VCD), with quantum mechanics (QM) ECD and VCD calculations. The traditional QM methods as well as their continuing developments make them more applicable with <span class="hlt">accuracy</span>. Taking some chiral natural products with diverse conformations as examples, this review describes the basic concepts and new developments of QM approaches for ECD and VCD calculations in solution and solid states.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2016JPhCS.733a2095D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2016JPhCS.733a2095D"><span id="translatedtitle">Metrological activity determination of 133Ba by sum-peak <span class="hlt">absolute</span> method</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>da Silva, R. L.; de Almeida, M. C. M.; Delgado, J. U.; Poledna, R.; Santos, A.; de Veras, E. V.; Rangel, J.; Trindade, O. L.</p> <p>2016-07-01</p> <p>The National Laboratory for Metrology of Ionizing Radiation provides gamma sources of radionuclide and standardized in activity with reduced uncertainties. Relative methods require standards to determine the sample activity while the <span class="hlt">absolute</span> methods, as sum-peak, not. The activity is obtained directly with good <span class="hlt">accuracy</span> and low uncertainties. 133Ba is used in research laboratories and on calibration of detectors for analysis in different work areas. Classical <span class="hlt">absolute</span> methods don't calibrate 133Ba due to its complex decay scheme. The sum-peak method using gamma spectrometry with germanium detector standardizes 133Ba samples. Uncertainties lower than 1% to activity results were obtained.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014AAS...22324516D','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014AAS...22324516D"><span id="translatedtitle">Enabling Dark Energy and Beyond Science with Precise <span class="hlt">Absolute</span> Photometry</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Deustua, Susana E.; Hines, D. C.; Bohlin, R.; Gordon, K. D.</p> <p>2014-01-01</p> <p>We have obtain WFC3/IR observations of 15 carefully selected stars with the immediate objective of establishing their <span class="hlt">Absolute</span> Physical Flux (ABF), and an ultimate goal of achieving the sub-1% <span class="hlt">absolute</span> photometric <span class="hlt">accuracies</span> required by Dark Energy science with JWST and other facilities. Even with the best data available, the current determination of ABFs is plagued by the reliance on the Vega photometric system, which is known to be problematic primarily due to the fact that Vega is a pole-on rapid rotator with an infrared excess from its circumstellar disk! which makes it difficult to model. Vega is also far too bright for large aperture telescopes. In an effort to remedy these difficulties, teams from the National Institute of Standards (NIST), the University of New Mexico, Johns Hopkins University and STScI have begun to develop a catalog of stars that have spectral energy distributions that are tied directly to NIST (diode) standards with very precisely determined physical characteristics. A key element in this pursuit has been the efforts at STScI to measure the spectra of many of these objects with STIS. We discuss our program to extend this effort into the near-IR which is crucial to reliably extend the SEDs to longer wavelengths, including the mid IR.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26215130','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26215130"><span id="translatedtitle">Real-<span class="hlt">time</span> PCR for detection of Strongyloides stercoralis in human stool samples from Côte d'Ivoire: diagnostic <span class="hlt">accuracy</span>, inter-laboratory comparison and patterns of hookworm co-infection.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Becker, Sören L; Piraisoody, Nivetha; Kramme, Stefanie; Marti, Hanspeter; Silué, Kigbafori D; Panning, Marcus; Nickel, Beatrice; Kern, Winfried V; Herrmann, Mathias; Hatz, Christoph F; N'Goran, Eliézer K; Utzinger, Jürg; von Müller, Lutz</p> <p>2015-10-01</p> <p>Human infections with the helminth species Strongyloides stercoralis encompass a wide clinical spectrum, ranging from asymptomatic carriage to life-threatening disease. The diagnosis of S. stercoralis is cumbersome and the sensitivity of conventional stool microscopy is low. New molecular tools have been developed to increase sensitivity. We compared the diagnostic <span class="hlt">accuracy</span> of real-<span class="hlt">time</span> PCR with microscopy for the detection of S. stercoralis and hookworm in human stool samples, and investigated the inter-laboratory agreement of S. stercoralis-specific real-<span class="hlt">time</span> PCR in two European laboratories. Stool specimens from 256 randomly selected individuals in rural Côte d'Ivoire were examined using three microscopic techniques (i.e. Kato-Katz, Koga agar plate (KAP) and Baermann (BM)). Additionally, ethanol-fixed stool aliquots were subjected to molecular diagnosis. The prevalence of S. stercoralis and hookworm infection was 21.9% and 52.0%, respectively, whilst co-infections were detected in 35 (13.7%) participants. The diagnostic agreement between real-<span class="hlt">time</span> PCR and microscopy was excellent when both KAP and BM tested positive for S. stercoralis, but was considerably lower when only one microscopic technique was positive. The sensitivity of KAP, BM and real-<span class="hlt">time</span> PCR for detection of S. stercoralis as compared to a combination of all diagnostic techniques was 21.4%, 37.5% and 76.8%, respectively. The inter-laboratory agreement of S. stercoralis-specific PCR was substantial (κ=0.63, p<0.001). We conclude that a combination of real-<span class="hlt">time</span> PCR and stool microscopy shows high <span class="hlt">accuracy</span> for S. stercoralis diagnosis. Besides high sensitivity, PCR may also enhance specificity by reducing microscopic misdiagnosis of morphologically similar helminth larvae (i.e. hookworm and S. stercoralis) in settings where both helminth species co-exist.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=84932&keyword=drones+OR+uav+OR+unmanned+AND+aerial+AND+vehicles&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=68444726&CFTOKEN=42852577','EPA-EIMS'); return false;" href="http://cfpub.epa.gov/si/si_public_record_report.cfm?dirEntryId=84932&keyword=drones+OR+uav+OR+unmanned+AND+aerial+AND+vehicles&actType=&TIMSType=+&TIMSSubTypeID=&DEID=&epaNumber=&ntisID=&archiveStatus=Both&ombCat=Any&dateBeginCreated=&dateEndCreated=&dateBeginPublishedPresented=&dateEndPublishedPresented=&dateBeginUpdated=&dateEndUpdated=&dateBeginCompleted=&dateEndCompleted=&personID=&role=Any&journalID=&publisherID=&sortBy=revisionDate&count=50&CFID=68444726&CFTOKEN=42852577"><span id="translatedtitle">GEOSPATIAL DATA <span class="hlt">ACCURACY</span> ASSESSMENT</span></a></p> <p><a target="_blank" href="http://oaspub.epa.gov/eims/query.page">EPA Science Inventory</a></p> <p></p> <p></p> <p>The development of robust <span class="hlt">accuracy</span> assessment methods for the validation of spatial data represent's a difficult scientific challenge for the geospatial science community. The importance and timeliness of this issue is related directly to the dramatic escalation in the developmen...</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20110022504','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20110022504"><span id="translatedtitle">Preliminary Error Budget for the Reflected Solar Instrument for the Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Thome, Kurtis; Gubbels, Timothy; Barnes, Robert</p> <p>2011-01-01</p> <p>The Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory (CLARREO) plans to observe climate change trends over decadal <span class="hlt">time</span> scales to determine the <span class="hlt">accuracy</span> of climate projections. The project relies on spaceborne earth observations of SI-traceable variables sensitive to key decadal change parameters. The mission includes a reflected solar instrument retrieving at-sensor reflectance over the 320 to 2300 nm spectral range with 500-m spatial resolution and 100-km swath. Reflectance is obtained from the ratio of measurements of the earth s surface to those while viewing the sun relying on a calibration approach that retrieves reflectance with uncertainties less than 0.3%. The calibration is predicated on heritage hardware, reduction of sensor complexity, adherence to detector-based calibration standards, and an ability to simulate in the laboratory on-orbit sources in both size and brightness to provide the basis of a transfer to orbit of the laboratory calibration including a link to <span class="hlt">absolute</span> solar irradiance measurements. The Climate <span class="hlt">Absolute</span> Radiance and Refractivity Observatory (CLARREO) mission addresses the need to observe high-<span class="hlt">accuracy</span>, long-term climate change trends and to use decadal change observations as the most critical method to determine the <span class="hlt">accuracy</span> of climate change projections such as those in the IPCC Report. A rigorously known <span class="hlt">accuracy</span> of both decadal change observations as well as climate projections is critical in order to enable sound policy decisions. The CLARREO Project will implement a spaceborne earth observation mission designed to provide rigorous SI traceable observations (i.e., radiance, reflectance, and refractivity) that are sensitive to a wide range of key decadal change variables, including: 1) Surface temperature and atmospheric temperature profile 2) Atmospheric water vapor profile 3) Far infrared water vapor greenhouse 4) Aerosol properties and anthropogenic aerosol direct radiative forcing 5) Total and spectral solar</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26729134','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26729134"><span id="translatedtitle">Bio-Inspired Stretchable <span class="hlt">Absolute</span> Pressure Sensor Network.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Guo, Yue; Li, Yu-Hung; Guo, Zhiqiang; Kim, Kyunglok; Chang, Fu-Kuo; Wang, Shan X</p> <p>2016-01-02</p> <p>A bio-inspired <span class="hlt">absolute</span> pressure sensor network has been developed. <span class="hlt">Absolute</span> pressure sensors, distributed on multiple silicon islands, are connected as a network by stretchable polyimide wires. This sensor network, made on a 4'' wafer, has 77 nodes and can be mounted on various curved surfaces to cover an area up to 0.64 m × 0.64 m, which is 100 <span class="hlt">times</span> larger than its original size. Due to Micro Electro-Mechanical system (MEMS) surface micromachining technology, ultrathin sensing nodes can be realized with thicknesses of less than 100 µm. Additionally, good linearity and high sensitivity (~14 mV/V/bar) have been achieved. Since the MEMS sensor process has also been well integrated with a flexible polymer substrate process, the entire sensor network can be fabricated in a <span class="hlt">time</span>-efficient and cost-effective manner. Moreover, an accurate pressure contour can be obtained from the sensor network. Therefore, this <span class="hlt">absolute</span> pressure sensor network holds significant promise for smart vehicle applications, especially for unmanned aerial vehicles.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4732088','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4732088"><span id="translatedtitle">Bio-Inspired Stretchable <span class="hlt">Absolute</span> Pressure Sensor Network</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Guo, Yue; Li, Yu-Hung; Guo, Zhiqiang; Kim, Kyunglok; Chang, Fu-Kuo; Wang, Shan X.</p> <p>2016-01-01</p> <p>A bio-inspired <span class="hlt">absolute</span> pressure sensor network has been developed. <span class="hlt">Absolute</span> pressure sensors, distributed on multiple silicon islands, are connected as a network by stretchable polyimide wires. This sensor network, made on a 4’’ wafer, has 77 nodes and can be mounted on various curved surfaces to cover an area up to 0.64 m × 0.64 m, which is 100 <span class="hlt">times</span> larger than its original size. Due to Micro Electro-Mechanical system (MEMS) surface micromachining technology, ultrathin sensing nodes can be realized with thicknesses of less than 100 µm. Additionally, good linearity and high sensitivity (~14 mV/V/bar) have been achieved. Since the MEMS sensor process has also been well integrated with a flexible polymer substrate process, the entire sensor network can be fabricated in a <span class="hlt">time</span>-efficient and cost-effective manner. Moreover, an accurate pressure contour can be obtained from the sensor network. Therefore, this <span class="hlt">absolute</span> pressure sensor network holds significant promise for smart vehicle applications, especially for unmanned aerial vehicles. PMID:26729134</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/26729134','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/26729134"><span id="translatedtitle">Bio-Inspired Stretchable <span class="hlt">Absolute</span> Pressure Sensor Network.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Guo, Yue; Li, Yu-Hung; Guo, Zhiqiang; Kim, Kyunglok; Chang, Fu-Kuo; Wang, Shan X</p> <p>2016-01-01</p> <p>A bio-inspired <span class="hlt">absolute</span> pressure sensor network has been developed. <span class="hlt">Absolute</span> pressure sensors, distributed on multiple silicon islands, are connected as a network by stretchable polyimide wires. This sensor network, made on a 4'' wafer, has 77 nodes and can be mounted on various curved surfaces to cover an area up to 0.64 m × 0.64 m, which is 100 <span class="hlt">times</span> larger than its original size. Due to Micro Electro-Mechanical system (MEMS) surface micromachining technology, ultrathin sensing nodes can be realized with thicknesses of less than 100 µm. Additionally, good linearity and high sensitivity (~14 mV/V/bar) have been achieved. Since the MEMS sensor process has also been well integrated with a flexible polymer substrate process, the entire sensor network can be fabricated in a <span class="hlt">time</span>-efficient and cost-effective manner. Moreover, an accurate pressure contour can be obtained from the sensor network. Therefore, this <span class="hlt">absolute</span> pressure sensor network holds significant promise for smart vehicle applications, especially for unmanned aerial vehicles. PMID:26729134</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015JMagR.261..121M','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015JMagR.261..121M"><span id="translatedtitle"><span class="hlt">Absolute</span> phase effects on CPMG-type pulse sequences</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Mandal, Soumyajit; Oh, Sangwon; Hürlimann, Martin D.</p> <p>2015-12-01</p> <p>We describe and analyze the effects of transients within radio-frequency (RF) pulses on multiple-pulse NMR measurements such as the well-known Carr-Purcell-Meiboom-Gill (CPMG) sequence. These transients are functions of the <span class="hlt">absolute</span> RF phases at the beginning and end of the pulse, and are thus affected by the <span class="hlt">timing</span> of the pulse sequence with respect to the period of the RF waveform. Changes in transients between refocusing pulses in CPMG-type sequences can result in signal decay, persistent oscillations, changes in echo shape, and other effects. We have explored such effects by performing experiments in two different low-frequency NMR systems. The first uses a conventional tuned-and-matched probe circuit, while the second uses an ultra-broadband un-tuned or non-resonant probe circuit. We show that there are distinct differences between the <span class="hlt">absolute</span> phase effects in these two systems, and present simple models that explain these differences.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/21241049','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/21241049"><span id="translatedtitle"><span class="hlt">Absolute</span> quantification of allergens from complex mixtures: a new sensitive tool for standardization of allergen extracts for specific immunotherapy.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Seppälä, Ulla; Dauly, Claire; Robinson, Sarah; Hornshaw, Martin; Larsen, Jørgen Nedergaard; Ipsen, Henrik</p> <p>2011-04-01</p> <p>Products for specific diagnosis and immunotherapy of IgE-mediated allergies are currently based on natural extracts. Quantification of major allergen content is an important aspect of standardization as important allergens particularly impact vaccine potency. The aim of the study was to develop a mass spectrometry (MS) based assay for <span class="hlt">absolute</span> quantification of Timothy (Phleum pratense) pollen allergens Phl p 1 and Phl p 5 in P. pratense extract. High-resolution and accurate mass (HRAM) MS was selected for its ability to detect peptides with high selectivity and mass <span class="hlt">accuracy</span> (<3 ppm). Isotope labeled heavy peptides were used for <span class="hlt">absolute</span> quantification of specific isoallergens of Phl p 1 and Phl p 5 at low femtomole level in P. pratense extract. Robustness and linearity of the method was demonstrated with intra day precision ≤ 5% (n = 3). Phl p 1b was shown to be 5 <span class="hlt">times</span> less abundant than its variant Phl p 1a and Phl p 5b was shown to be 9 <span class="hlt">times</span> more abundant than the Phl p 5a. The present study shows that allergen, and/or isoallergen specific, surrogate signature peptides analyzed with HRAM MS is a sensitive and accurate tool for identification and quantification of allergens from complex allergen sources.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/25997164','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/25997164"><span id="translatedtitle">A multilaboratory comparison of calibration <span class="hlt">accuracy</span> and the performance of external references in analytical ultracentrifugation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhao, Huaying; Ghirlando, Rodolfo; Alfonso, Carlos; Arisaka, Fumio; Attali, Ilan; Bain, David L; Bakhtina, Marina M; Becker, Donald F; Bedwell, Gregory J; Bekdemir, Ahmet; Besong, Tabot M D; Birck, Catherine; Brautigam, Chad A; Brennerman, William; Byron, Olwyn; Bzowska, Agnieszka; Chaires, Jonathan B; Chaton, Catherine T; Cölfen, Helmut; Connaghan, Keith D; Crowley, Kimberly A; Curth, Ute; Daviter, Tina; Dean, William L; Díez, Ana I; Ebel, Christine; Eckert, Debra M; Eisele, Leslie E; Eisenstein, Edward; England, Patrick; Escalante, Carlos; Fagan, Jeffrey A; Fairman, Robert; Finn, Ron M; Fischle, Wolfgang; de la Torre, José García; Gor, Jayesh; Gustafsson, Henning; Hall, Damien; Harding, Stephen E; Cifre, José G Hernández; Herr, Andrew B; Howell, Elizabeth E; Isaac, Richard S; Jao, Shu-Chuan; Jose, Davis; Kim, Soon-Jong; Kokona, Bashkim; Kornblatt, Jack A; Kosek, Dalibor; Krayukhina, Elena; Krzizike, Daniel; Kusznir, Eric A; Kwon, Hyewon; Larson, Adam; Laue, Thomas M; Le Roy, Aline; Leech, Andrew P; Lilie, Hauke; Luger, Karolin; Luque-Ortega, Juan R; Ma, Jia; May, Carrie A; Maynard, Ernest L; Modrak-Wojcik, Anna; Mok, Yee-Foong; Mücke, Norbert; Nagel-Steger, Luitgard; Narlikar, Geeta J; Noda, Masanori; Nourse, Amanda; Obsil, Tomas; Park, Chad K; Park, Jin-Ku; Pawelek, Peter D; Perdue, Erby E; Perkins, Stephen J; Perugini, Matthew A; Peterson, Craig L; Peverelli, Martin G; Piszczek, Grzegorz; Prag, Gali; Prevelige, Peter E; Raynal, Bertrand D E; Rezabkova, Lenka; Richter, Klaus; Ringel, Alison E; Rosenberg, Rose; Rowe, Arthur J; Rufer, Arne C; Scott, David J; Seravalli, Javier G; Solovyova, Alexandra S; Song, Renjie; Staunton, David; Stoddard, Caitlin; Stott, Katherine; Strauss, Holger M; Streicher, Werner W; Sumida, John P; Swygert, Sarah G; Szczepanowski, Roman H; Tessmer, Ingrid; Toth, Ronald T; Tripathy, Ashutosh; Uchiyama, Susumu; Uebel, Stephan F W; Unzai, Satoru; Gruber, Anna Vitlin; von Hippel, Peter H; Wandrey, Christine; Wang, Szu-Huan; Weitzel, Steven E; Wielgus-Kutrowska, Beata; Wolberger, Cynthia; Wolff, Martin; Wright, Edward; Wu, Yu-Sung; Wubben, Jacinta M; Schuck, Peter</p> <p>2015-01-01</p> <p>Analytical ultracentrifugation (AUC) is a first principles based method to determine <span class="hlt">absolute</span> sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this multi-laboratory study was to establish the precision and <span class="hlt">accuracy</span> of basic data dimensions in AUC and validate previously proposed calibration techniques. Three kits of AUC cell assemblies containing radial and temperature calibration tools and a bovine serum albumin (BSA) reference sample were shared among 67 laboratories, generating 129 comprehensive data sets. These allowed for an assessment of many parameters of instrument performance, including <span class="hlt">accuracy</span> of the reported scan <span class="hlt">time</span> after the start of centrifugation, the <span class="hlt">accuracy</span> of the temperature calibration, and the <span class="hlt">accuracy</span> of the radial magnification. The range of sedimentation coefficients obtained for BSA monomer in different instruments and using different optical systems was from 3.655 S to 4.949 S, with a mean and standard deviation of (4.304 ± 0.188) S (4.4%). After the combined application of correction factors derived from the external calibration references for elapsed <span class="hlt">time</span>, scan velocity, temperature, and radial magnification, the range of s-values was reduced 7-fold with a mean of 4.325 S and a 6-fold reduced standard deviation of ± 0.030 S (0.7%). In addition, the large data set provided an opportunity to determine the instrument-to-instrument variation of the <span class="hlt">absolute</span> radial positions reported in the scan files, the precision of photometric or refractometric signal magnitudes, and the precision of the calculated apparent molar mass of BSA monomer and the fraction of BSA dimers. These results highlight the necessity and effectiveness of independent calibration of basic AUC data dimensions for reliable quantitative studies.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25997164','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25997164"><span id="translatedtitle">A multilaboratory comparison of calibration <span class="hlt">accuracy</span> and the performance of external references in analytical ultracentrifugation.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Zhao, Huaying; Ghirlando, Rodolfo; Alfonso, Carlos; Arisaka, Fumio; Attali, Ilan; Bain, David L; Bakhtina, Marina M; Becker, Donald F; Bedwell, Gregory J; Bekdemir, Ahmet; Besong, Tabot M D; Birck, Catherine; Brautigam, Chad A; Brennerman, William; Byron, Olwyn; Bzowska, Agnieszka; Chaires, Jonathan B; Chaton, Catherine T; Cölfen, Helmut; Connaghan, Keith D; Crowley, Kimberly A; Curth, Ute; Daviter, Tina; Dean, William L; Díez, Ana I; Ebel, Christine; Eckert, Debra M; Eisele, Leslie E; Eisenstein, Edward; England, Patrick; Escalante, Carlos; Fagan, Jeffrey A; Fairman, Robert; Finn, Ron M; Fischle, Wolfgang; de la Torre, José García; Gor, Jayesh; Gustafsson, Henning; Hall, Damien; Harding, Stephen E; Cifre, José G Hernández; Herr, Andrew B; Howell, Elizabeth E; Isaac, Richard S; Jao, Shu-Chuan; Jose, Davis; Kim, Soon-Jong; Kokona, Bashkim; Kornblatt, Jack A; Kosek, Dalibor; Krayukhina, Elena; Krzizike, Daniel; Kusznir, Eric A; Kwon, Hyewon; Larson, Adam; Laue, Thomas M; Le Roy, Aline; Leech, Andrew P; Lilie, Hauke; Luger, Karolin; Luque-Ortega, Juan R; Ma, Jia; May, Carrie A; Maynard, Ernest L; Modrak-Wojcik, Anna; Mok, Yee-Foong; Mücke, Norbert; Nagel-Steger, Luitgard; Narlikar, Geeta J; Noda, Masanori; Nourse, Amanda; Obsil, Tomas; Park, Chad K; Park, Jin-Ku; Pawelek, Peter D; Perdue, Erby E; Perkins, Stephen J; Perugini, Matthew A; Peterson, Craig L; Peverelli, Martin G; Piszczek, Grzegorz; Prag, Gali; Prevelige, Peter E; Raynal, Bertrand D E; Rezabkova, Lenka; Richter, Klaus; Ringel, Alison E; Rosenberg, Rose; Rowe, Arthur J; Rufer, Arne C; Scott, David J; Seravalli, Javier G; Solovyova, Alexandra S; Song, Renjie; Staunton, David; Stoddard, Caitlin; Stott, Katherine; Strauss, Holger M; Streicher, Werner W; Sumida, John P; Swygert, Sarah G; Szczepanowski, Roman H; Tessmer, Ingrid; Toth, Ronald T; Tripathy, Ashutosh; Uchiyama, Susumu; Uebel, Stephan F W; Unzai, Satoru; Gruber, Anna Vitlin; von Hippel, Peter H; Wandrey, Christine; Wang, Szu-Huan; Weitzel, Steven E; Wielgus-Kutrowska, Beata; Wolberger, Cynthia; Wolff, Martin; Wright, Edward; Wu, Yu-Sung; Wubben, Jacinta M; Schuck, Peter</p> <p>2015-01-01</p> <p>Analytical ultracentrifugation (AUC) is a first principles based method to determine <span class="hlt">absolute</span> sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this multi-laboratory study was to establish the precision and <span class="hlt">accuracy</span> of basic data dimensions in AUC and validate previously proposed calibration techniques. Three kits of AUC cell assemblies containing radial and temperature calibration tools and a bovine serum albumin (BSA) reference sample were shared among 67 laboratories, generating 129 comprehensive data sets. These allowed for an assessment of many parameters of instrument performance, including <span class="hlt">accuracy</span> of the reported scan <span class="hlt">time</span> after the start of centrifugation, the <span class="hlt">accuracy</span> of the temperature calibration, and the <span class="hlt">accuracy</span> of the radial magnification. The range of sedimentation coefficients obtained for BSA monomer in different instruments and using different optical systems was from 3.655 S to 4.949 S, with a mean and standard deviation of (4.304 ± 0.188) S (4.4%). After the combined application of correction factors derived from the external calibration references for elapsed <span class="hlt">time</span>, scan velocity, temperature, and radial magnification, the range of s-values was reduced 7-fold with a mean of 4.325 S and a 6-fold reduced standard deviation of ± 0.030 S (0.7%). In addition, the large data set provided an opportunity to determine the instrument-to-instrument variation of the <span class="hlt">absolute</span> radial positions reported in the scan files, the precision of photometric or refractometric signal magnitudes, and the precision of the calculated apparent molar mass of BSA monomer and the fraction of BSA dimers. These results highlight the necessity and effectiveness of independent calibration of basic AUC data dimensions for reliable quantitative studies. PMID:25997164</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4440767','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=4440767"><span id="translatedtitle">A Multilaboratory Comparison of Calibration <span class="hlt">Accuracy</span> and the Performance of External References in Analytical Ultracentrifugation</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Zhao, Huaying; Ghirlando, Rodolfo; Alfonso, Carlos; Arisaka, Fumio; Attali, Ilan; Bain, David L.; Bakhtina, Marina M.; Becker, Donald F.; Bedwell, Gregory J.; Bekdemir, Ahmet; Besong, Tabot M. D.; Birck, Catherine; Brautigam, Chad A.; Brennerman, William; Byron, Olwyn; Bzowska, Agnieszka; Chaires, Jonathan B.; Chaton, Catherine T.; Cölfen, Helmut; Connaghan, Keith D.; Crowley, Kimberly A.; Curth, Ute; Daviter, Tina; Dean, William L.; Díez, Ana I.; Ebel, Christine; Eckert, Debra M.; Eisele, Leslie E.; Eisenstein, Edward; England, Patrick; Escalante, Carlos; Fagan, Jeffrey A.; Fairman, Robert; Finn, Ron M.; Fischle, Wolfgang; de la Torre, José García; Gor, Jayesh; Gustafsson, Henning; Hall, Damien; Harding, Stephen E.; Cifre, José G. Hernández; Herr, Andrew B.; Howell, Elizabeth E.; Isaac, Richard S.; Jao, Shu-Chuan; Jose, Davis; Kim, Soon-Jong; Kokona, Bashkim; Kornblatt, Jack A.; Kosek, Dalibor; Krayukhina, Elena; Krzizike, Daniel; Kusznir, Eric A.; Kwon, Hyewon; Larson, Adam; Laue, Thomas M.; Le Roy, Aline; Leech, Andrew P.; Lilie, Hauke; Luger, Karolin; Luque-Ortega, Juan R.; Ma, Jia; May, Carrie A.; Maynard, Ernest L.; Modrak-Wojcik, Anna; Mok, Yee-Foong; Mücke, Norbert; Nagel-Steger, Luitgard; Narlikar, Geeta J.; Noda, Masanori; Nourse, Amanda; Obsil, Tomas; Park, Chad K.; Park, Jin-Ku; Pawelek, Peter D.; Perdue, Erby E.; Perkins, Stephen J.; Perugini, Matthew A.; Peterson, Craig L.; Peverelli, Martin G.; Piszczek, Grzegorz; Prag, Gali; Prevelige, Peter E.; Raynal, Bertrand D. E.; Rezabkova, Lenka; Richter, Klaus; Ringel, Alison E.; Rosenberg, Rose; Rowe, Arthur J.; Rufer, Arne C.; Scott, David J.; Seravalli, Javier G.; Solovyova, Alexandra S.; Song, Renjie; Staunton, David; Stoddard, Caitlin; Stott, Katherine; Strauss, Holger M.; Streicher, Werner W.; Sumida, John P.; Swygert, Sarah G.; Szczepanowski, Roman H.; Tessmer, Ingrid; Toth, Ronald T.; Tripathy, Ashutosh; Uchiyama, Susumu; Uebel, Stephan F. W.; Unzai, Satoru; Gruber, Anna Vitlin; von Hippel, Peter H.; Wandrey, Christine; Wang, Szu-Huan; Weitzel, Steven E.; Wielgus-Kutrowska, Beata; Wolberger, Cynthia; Wolff, Martin; Wright, Edward; Wu, Yu-Sung; Wubben, Jacinta M.; Schuck, Peter</p> <p>2015-01-01</p> <p>Analytical ultracentrifugation (AUC) is a first principles based method to determine <span class="hlt">absolute</span> sedimentation coefficients and buoyant molar masses of macromolecules and their complexes, reporting on their size and shape in free solution. The purpose of this multi-laboratory study was to establish the precision and <span class="hlt">accuracy</span> of basic data dimensions in AUC and validate previously proposed calibration techniques. Three kits of AUC cell assemblies containing radial and temperature calibration tools and a bovine serum albumin (BSA) reference sample were shared among 67 laboratories, generating 129 comprehensive data sets. These allowed for an assessment of many parameters of instrument performance, including <span class="hlt">accuracy</span> of the reported scan <span class="hlt">time</span> after the start of centrifugation, the <span class="hlt">accuracy</span> of the temperature calibration, and the <span class="hlt">accuracy</span> of the radial magnification. The range of sedimentation coefficients obtained for BSA monomer in different instruments and using different optical systems was from 3.655 S to 4.949 S, with a mean and standard deviation of (4.304 ± 0.188) S (4.4%). After the combined application of correction factors derived from the external calibration references for elapsed <span class="hlt">time</span>, scan velocity, temperature, and radial magnification, the range of s-values was reduced 7-fold with a mean of 4.325 S and a 6-fold reduced standard deviation of ± 0.030 S (0.7%). In addition, the large data set provided an opportunity to determine the instrument-to-instrument variation of the <span class="hlt">absolute</span> radial positions reported in the scan files, the precision of photometric or refractometric signal magnitudes, and the precision of the calculated apparent molar mass of BSA monomer and the fraction of BSA dimers. These results highlight the necessity and effectiveness of independent calibration of basic AUC data dimensions for reliable quantitative studies. PMID:25997164</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2012SPIE.8324E..17K','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2012SPIE.8324E..17K"><span id="translatedtitle">Overlay <span class="hlt">accuracy</span> fundamentals</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Kandel, Daniel; Levinski, Vladimir; Sapiens, Noam; Cohen, Guy; Amit, Eran; Klein, Dana; Vakshtein, Irina</p> <p>2012-03-01</p> <p>Currently, the performance of overlay metrology is evaluated mainly based on random error contributions such as precision and TIS variability. With the expected shrinkage of the overlay metrology budget to < 0.5nm, it becomes crucial to include also systematic error contributions which affect the <span class="hlt">accuracy</span> of the metrology. Here we discuss fundamental aspects of overlay <span class="hlt">accuracy</span> and a methodology to improve <span class="hlt">accuracy</span> significantly. We identify overlay mark imperfections and their interaction with the metrology technology, as the main source of overlay inaccuracy. The most important type of mark imperfection is mark asymmetry. Overlay mark asymmetry leads to a geometrical ambiguity in the definition of overlay, which can be ~1nm or less. It is shown theoretically and in simulations that the metrology may enhance the effect of overlay mark asymmetry significantly and lead to metrology inaccuracy ~10nm, much larger than the geometrical ambiguity. The analysis is carried out for two different overlay metrology technologies: Imaging overlay and DBO (1st order diffraction based overlay). It is demonstrated that the sensitivity of DBO to overlay mark asymmetry is larger than the sensitivity of imaging overlay. Finally, we show that a recently developed measurement quality metric serves as a valuable tool for improving overlay metrology <span class="hlt">accuracy</span>. Simulation results demonstrate that the <span class="hlt">accuracy</span> of imaging overlay can be improved significantly by recipe setup optimized using the quality metric. We conclude that imaging overlay metrology, complemented by appropriate use of measurement quality metric, results in optimal overlay <span class="hlt">accuracy</span>.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=cell+AND+size&pg=4&id=EJ753903','ERIC'); return false;" href="http://eric.ed.gov/?q=cell+AND+size&pg=4&id=EJ753903"><span id="translatedtitle"><span class="hlt">Absolute</span> Points for Multiple Assignment Problems</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Adlakha, V.; Kowalski, K.</p> <p>2006-01-01</p> <p>An algorithm is presented to solve multiple assignment problems in which a cost is incurred only when an assignment is made at a given cell. The proposed method recursively searches for single/group <span class="hlt">absolute</span> points to identify cells that must be loaded in any optimal solution. Unlike other methods, the first solution is the optimal solution. The…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/927741','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/927741"><span id="translatedtitle"><span class="hlt">Absolute</span> partial photoionization cross sections of ozone.</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Berkowitz, J.; Chemistry</p> <p>2008-04-01</p> <p>Despite the current concerns about ozone, <span class="hlt">absolute</span> partial photoionization cross sections for this molecule in the vacuum ultraviolet (valence) region have been unavailable. By eclectic re-evaluation of old/new data and plausible assumptions, such cross sections have been assembled to fill this void.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=mathematics+AND+inequalities&pg=5&id=EJ945042','ERIC'); return false;" href="http://eric.ed.gov/?q=mathematics+AND+inequalities&pg=5&id=EJ945042"><span id="translatedtitle">Teaching <span class="hlt">Absolute</span> Value Inequalities to Mature Students</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Sierpinska, Anna; Bobos, Georgeana; Pruncut, Andreea</p> <p>2011-01-01</p> <p>This paper gives an account of a teaching experiment on <span class="hlt">absolute</span> value inequalities, whose aim was to identify characteristics of an approach that would realize the potential of the topic to develop theoretical thinking in students enrolled in prerequisite mathematics courses at a large, urban North American university. The potential is…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=VALUE+AND+ABSOLUTE&pg=2&id=EJ726176','ERIC'); return false;" href="http://eric.ed.gov/?q=VALUE+AND+ABSOLUTE&pg=2&id=EJ726176"><span id="translatedtitle">Solving <span class="hlt">Absolute</span> Value Equations Algebraically and Geometrically</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Shiyuan, Wei</p> <p>2005-01-01</p> <p>The way in which students can improve their comprehension by understanding the geometrical meaning of algebraic equations or solving algebraic equation geometrically is described. Students can experiment with the conditions of the <span class="hlt">absolute</span> value equation presented, for an interesting way to form an overall understanding of the concept.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li class="active"><span>24</span></li> <li><a href="#" onclick='return showDiv("page_25");'>25</a></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_24 --> <div id="page_25" class="hiddenDiv"> <div class="row"> <div class="col-sm-12"> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div> </div> <div class="row"> <div class="col-sm-12"> <ol class="result-class" start="481"> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=limit+AND+articles&pg=2&id=EJ933808','ERIC'); return false;" href="http://eric.ed.gov/?q=limit+AND+articles&pg=2&id=EJ933808"><span id="translatedtitle">Increasing Capacity: Practice Effects in <span class="hlt">Absolute</span> Identification</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Dodds, Pennie; Donkin, Christopher; Brown, Scott D.; Heathcote, Andrew</p> <p>2011-01-01</p> <p>In most of the long history of the study of <span class="hlt">absolute</span> identification--since Miller's (1956) seminal article--a severe limit on performance has been observed, and this limit has resisted improvement even by extensive practice. In a startling result, Rouder, Morey, Cowan, and Pfaltz (2004) found substantially improved performance with practice in the…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/1986SPIE..660....2S','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/1986SPIE..660....2S"><span id="translatedtitle"><span class="hlt">Absolute</span> Radiometric Calibration Of The Thematic Mapper</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Slater, P. N.; Biggar, S. F.; Holm, R. G.; Jackson, R. D.; Mao, Y.; Moran, M. S.; Palmer, J. M.; Yuan, B.</p> <p>1986-11-01</p> <p>The results are presented of five in-flight <span class="hlt">absolute</span> radiometric calibrations, made in the period July 1984 to November 1985, at White Sands, New Mexico, of the solar reflective bands of the Landsat-5 Thematic Mapper (TM) . The 23 bandcalibrations made on the five dates show a ± 2.8% RMS variation from the mean as a percentage of the mean.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://eric.ed.gov/?q=mathematics+AND+education&pg=5&id=EJ1070973','ERIC'); return false;" href="http://eric.ed.gov/?q=mathematics+AND+education&pg=5&id=EJ1070973"><span id="translatedtitle">On Relative and <span class="hlt">Absolute</span> Conviction in Mathematics</span></a></p> <p><a target="_blank" href="http://www.eric.ed.gov/ERICWebPortal/search/extended.jsp?_pageLabel=advanced">ERIC Educational Resources Information Center</a></p> <p>Weber, Keith; Mejia-Ramos, Juan Pablo</p> <p>2015-01-01</p> <p>Conviction is a central construct in mathematics education research on justification and proof. In this paper, we claim that it is important to distinguish between <span class="hlt">absolute</span> conviction and relative conviction. We argue that researchers in mathematics education frequently have not done so and this has lead to researchers making unwarranted claims…</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19900017555','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19900017555"><span id="translatedtitle"><span class="hlt">Accuracy</span> analysis of the space shuttle solid rocket motor profile measuring device</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Estler, W. Tyler</p> <p>1989-01-01</p> <p>The Profile Measuring Device (PMD) was developed at the George C. Marshall Space Flight Center following the loss of the Space Shuttle Challenger. It is a rotating gauge used to measure the <span class="hlt">absolute</span> diameters of mating features of redesigned Solid Rocket Motor field joints. Diameter tolerance of these features are typically + or - 0.005 inches and it is required that the PMD <span class="hlt">absolute</span> measurement uncertainty be within this tolerance. In this analysis, the <span class="hlt">absolute</span> <span class="hlt">accuracy</span> of these measurements were found to be + or - 0.00375 inches, worst case, with a potential <span class="hlt">accuracy</span> of + or - 0.0021 inches achievable by improved temperature control.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/19285350','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/19285350"><span id="translatedtitle">Comparable performance of patients with obsessive-compulsive disorder (OCD) and healthy controls for verbal and nonverbal memory <span class="hlt">accuracy</span> and confidence: <span class="hlt">time</span> to forget the forgetfulness hypothesis of OCD?</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Moritz, Steffen; Kloss, Martin; von Eckstaedt, Francesca Vitzthum; Jelinek, Lena</p> <p>2009-04-30</p> <p>The memory deficit or forgetfulness hypothesis of obsessive-compulsive disorder (OCD) has received considerable attention and empirical effort over the past decades. The present study aimed to provide a fair test of its various formulations: (1) memory dysfunction in OCD is ubiquitous, that is, manifests irrespective of modality and material; (2) memory dysfunction is found for nonverbal but not verbal material, (3) memory dysfunction is secondary to executive impairment; and (4) memory dysfunction affects meta-memory rather than memory <span class="hlt">accuracy</span>. Participants comprised 43 OCD patients and 46 healthy controls who were tested on the Picture Word Memory Test (PWMT), which provides several unconfounded parameters for nonverbal and verbal memory <span class="hlt">accuracy</span> and confidence measures across different <span class="hlt">time</span>-points. In addition, the Trail-Making Test B was administered to test assumption number 3. Replicating earlier work of our group, samples displayed similar performance on all indices. None of the different formulations of the memory deficit hypothesis were supported. In view of waning evidence for a global memory deficit in OCD, neuropsychological research on OCD should more thoroughly investigate moderators and triggers of occasional instances of impaired performance, particularly cognitive biases such as perfectionism and an inflated sense of responsibility. PMID:19285350</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2015AGUFMGP43C1255H','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2015AGUFMGP43C1255H"><span id="translatedtitle">The <span class="hlt">Absolute</span> Vector Magnetometers on Board Swarm, Lessons Learned From Two Years in Space.</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Hulot, G.; Leger, J. M.; Vigneron, P.; Brocco, L.; Olsen, N.; Jager, T.; Bertrand, F.; Fratter, I.; Sirol, O.; Lalanne, X.</p> <p>2015-12-01</p> <p>ESA's Swarm satellites carry 4He <span class="hlt">absolute</span> magnetometers (ASM), designed by CEA-Léti and developed in partnership with CNES. These instruments are the first-ever space-born magnetometers to use a common sensor to simultaneously deliver 1Hz independent <span class="hlt">absolute</span> scalar and vector readings of the magnetic field. They have provided the very high <span class="hlt">accuracy</span> scalar field data nominally required by the mission (for both science and calibration purposes, since each satellite also carries a low noise high frequency fluxgate magnetometer designed by DTU), but also very useful experimental <span class="hlt">absolute</span> vector data. In this presentation, we will report on the status of the instruments, as well as on the various tests and investigations carried out using these experimental data since launch in November 2013. In particular, we will illustrate the advantages of flying ASM instruments on space-born magnetic missions for nominal data quality checks, geomagnetic field modeling and science objectives.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/26125394','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/26125394"><span id="translatedtitle">Measurement of <span class="hlt">absolute</span> optical thickness of mask glass by wavelength-tuning Fourier analysis.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Kim, Yangjin; Hbino, Kenichi; Sugita, Naohiko; Mitsuishi, Mamoru</p> <p>2015-07-01</p> <p>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 <span class="hlt">absolute</span> 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 <span class="hlt">absolute</span> 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 <span class="hlt">absolute</span> optical thickness of mask glass was measured with an <span class="hlt">accuracy</span> of 5 nm.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://adsabs.harvard.edu/abs/2014APhy...60..687L','NASAADS'); return false;" href="http://adsabs.harvard.edu/abs/2014APhy...60..687L"><span id="translatedtitle"><span class="hlt">Accuracy</span> in determining voice source parameters</span></a></p> <p><a target="_blank" href="http://adsabs.harvard.edu/abstract_service.html">NASA Astrophysics Data System (ADS)</a></p> <p>Leonov, A. S.; Sorokin, V. N.</p> <p>2014-11-01</p> <p>The paper addresses the <span class="hlt">accuracy</span> of an approximate solution to the inverse problem of retrieving the shape of a voice source from a speech signal for a known signal-to-noise ratio (SNR). It is shown that if the source is found as a function of <span class="hlt">time</span> with the A.N. Tikhonov regularization method, the <span class="hlt">accuracy</span> of the found approximation is worse than the <span class="hlt">accuracy</span> of speech signal recording by an order of magnitude. In contrast, adequate parameterization of the source ensures approximate solution <span class="hlt">accuracy</span> comparable with the <span class="hlt">accuracy</span> of the problem data. A corresponding algorithm is considered. On the basis of linear (in terms of data errors) estimates of approximate parametric solution <span class="hlt">accuracy</span>, parametric models with the best <span class="hlt">accuracy</span> can be chosen. This comparison has been carried out for the known voice source models, i.e., model [17] and the LF model [18]. The advantages of the latter are shown. Thus, for SNR = 40 dB, the relative <span class="hlt">accuracy</span> of an approximate solution found with this algorithm is about 1% for the LF model and about 2% for model [17] as compared to an <span class="hlt">accuracy</span> of 7-8% in the regularization method. The role of <span class="hlt">accuracy</span> estimates found in speaker identification problems is discussed.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22047190','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22047190"><span id="translatedtitle"><span class="hlt">Absolute</span> photoionization cross-section of the propargyl radical</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Savee, John D.; Welz, Oliver; Taatjes, Craig A.; Osborn, David L.; Soorkia, Satchin; Selby, Talitha M.</p> <p>2012-04-07</p> <p>Using synchrotron-generated vacuum-ultraviolet radiation and multiplexed <span class="hlt">time</span>-resolved photoionization mass spectrometry we have measured the <span class="hlt">absolute</span> photoionization cross-section for the propargyl (C{sub 3}H{sub 3}) radical, {sigma}{sub propargyl}{sup ion}(E), relative to the known <span class="hlt">absolute</span> cross-section of the methyl (CH{sub 3}) radical. We generated a stoichiometric 1:1 ratio of C{sub 3}H{sub 3} : CH{sub 3} from 193 nm photolysis of two different C{sub 4}H{sub 6} isomers (1-butyne and 1,3-butadiene). Photolysis of 1-butyne yielded values of {sigma}{sub propargyl}{sup ion}(10.213 eV)=(26.1{+-}4.2) Mb and {sigma}{sub propargyl}{sup ion}(10.413 eV)=(23.4{+-}3.2) Mb, whereas photolysis of 1,3-butadiene yielded values of {sigma}{sub propargyl}{sup ion}(10.213 eV)=(23.6{+-}3.6) Mb and {sigma}{sub propargyl}{sup ion}(10.413 eV)=(25.1{+-}3.5) Mb. These measurements place our relative photoionization cross-section spectrum for propargyl on an <span class="hlt">absolute</span> scale between 8.6 and 10.5 eV. The cross-section derived from our results is approximately a factor of three larger than previous determinations.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/17724340','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/17724340"><span id="translatedtitle">Dichotomy and perceptual distortions in <span class="hlt">absolute</span> pitch ability.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Athos, E Alexandra; Levinson, Barbara; Kistler, Amy; Zemansky, Jason; Bostrom, Alan; Freimer, Nelson; Gitschier, Jane</p> <p>2007-09-11</p> <p><span class="hlt">Absolute</span> pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the <span class="hlt">accuracy</span> of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved to have extraordinary pitch-naming ability. The bimodal distribution in pitch-naming ability signifies AP as a distinct perceptual trait, with possible implications for its genetic basis. The wealth of these data has allowed us to uncover unsuspected note-naming irregularities suggestive of a "perceptual magnet" centered at the note "A." In addition, we document a gradual decline in pitch-naming <span class="hlt">accuracy</span> with age, characterized by a perceptual shift in the "sharp" direction. These findings speak both to the process of acquisition of AP and to its stability.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1959403','PMC'); return false;" href="https://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1959403"><span id="translatedtitle">Dichotomy and perceptual distortions in <span class="hlt">absolute</span> pitch ability</span></a></p> <p><a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pmc">PubMed Central</a></p> <p>Athos, E. Alexandra; Levinson, Barbara; Kistler, Amy; Zemansky, Jason; Bostrom, Alan; Freimer, Nelson; Gitschier, Jane</p> <p>2007-01-01</p> <p><span class="hlt">Absolute</span> pitch (AP) is the rare ability to identify the pitch of a tone without the aid of a reference tone. Understanding both the nature and genesis of AP can provide insights into neuroplasticity in the auditory system. We explored factors that may influence the <span class="hlt">accuracy</span> of pitch perception in AP subjects both during the development of the trait and in later age. We used a Web-based survey and a pitch-labeling test to collect perceptual data from 2,213 individuals, 981 (44%) of whom proved to have extraordinary pitch-naming ability. The bimodal distribution in pitch-naming ability signifies AP as a distinct perceptual trait, with possible implications for its genetic basis. The wealth of these data has allowed us to uncover unsuspected note-naming irregularities suggestive of a “perceptual magnet” centered at the note “A.” In addition, we document a gradual decline in pitch-naming <span class="hlt">accuracy</span> with age, characterized by a perceptual shift in the “sharp” direction. These findings speak both to the process of acquisition of AP and to its stability. PMID:17724340</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/25423049','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/25423049"><span id="translatedtitle">Probing <span class="hlt">absolute</span> spin polarization at the nanoscale.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Eltschka, Matthias; Jäck, Berthold; Assig, Maximilian; Kondrashov, Oleg V; Skvortsov, Mikhail A; Etzkorn, Markus; Ast, Christian R; Kern, Klaus</p> <p>2014-12-10</p> <p>Probing <span class="hlt">absolute</span> values of spin polarization at the nanoscale offers insight into the fundamental mechanisms of spin-dependent transport. Employing the Zeeman splitting in superconducting tips (Meservey-Tedrow-Fulde effect), we introduce a novel spin-polarized scanning tunneling microscopy that combines the probing capability of the <span class="hlt">absolute</span> values of spin polarization with precise control at the atomic scale. We utilize our novel approach to measure the locally resolved spin polarization of magnetic Co nanoislands on Cu(111). We find that the spin polarization is enhanced by 65% when increasing the width of the tunnel barrier by only 2.3 Å due to the different decay of the electron orbitals into vacuum. PMID:25423049</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19750063653&hterms=VALUE+ABSOLUTE&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DVALUE%2BABSOLUTE','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19750063653&hterms=VALUE+ABSOLUTE&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D80%26Ntt%3DVALUE%2BABSOLUTE"><span id="translatedtitle"><span class="hlt">Absolute</span> radiometry and the solar constant</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Willson, R. C.</p> <p>1974-01-01</p> <p>A series of active cavity radiometers (ACRs) are described which have been developed as standard detectors for the accurate measurement of irradiance in <span class="hlt">absolute</span> units. It is noted that the ACR is an electrical substitution calorimeter, is designed for automatic remote operation in any environment, and can make irradiance measurements in the range from low-level IR fluxes up to 30 solar constants with small <span class="hlt">absolute</span> uncertainty. The instrument operates in a differential mode by chopping the radiant flux to be measured at a slow rate, and irradiance is determined from two electrical power measurements together with the instrumental constant. Results are reported for measurements of the solar constant with two types of ACRs. The more accurate measurement yielded a value of 136.6 plus or minus 0.7 mW/sq cm (1.958 plus or minus 0.010 cal/sq cm per min).</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/20120011123','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/20120011123"><span id="translatedtitle">From Hubble's NGSL to <span class="hlt">Absolute</span> Fluxes</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Heap, Sara R.; Lindler, Don</p> <p>2012-01-01</p> <p>Hubble's Next Generation Spectral Library (NGSL) consists of R-l000 spectra of 374 stars of assorted temperature, gravity, and metallicity. Each spectrum covers the wavelength range, 0.18-1.00 microns. The library can be viewed and/or downloaded from the website, http://archive.stsci.edu/prepds/stisngsll. Stars in the NGSL are now being used as <span class="hlt">absolute</span> flux standards at ground-based observatories. However, the uncertainty in the <span class="hlt">absolute</span> flux is about 2%, which does not meet the requirements of dark-energy surveys. We are therefore developing an observing procedure that should yield fluxes with uncertainties less than 1 % and will take part in an HST proposal to observe up to 15 stars using this new procedure.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('https://www.ncbi.nlm.nih.gov/pubmed/15281420','PUBMED'); return false;" href="https://www.ncbi.nlm.nih.gov/pubmed/15281420"><span id="translatedtitle">Impact of Winko on <span class="hlt">absolute</span> discharges.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Balachandra, Krishna; Swaminath, Sam; Litman, Larry C</p> <p>2004-01-01</p> <p>In Canada, case laws have had a significant impact on the way mentally ill offenders are managed, both in the criminal justice system and in the forensic mental health system. The Supreme Court of Canada's decision with respect to Winko has set a major precedent in the application of the test of significant risk to the safety of the public in making dispositions by the Ontario Review Board and granting <span class="hlt">absolute</span> discharges to the mentally ill offenders in the forensic health system. Our study examines the impact of the Supreme Court of Canada's decision before and after Winko. The results show that the numbers of <span class="hlt">absolute</span> discharges have increased post-Winko, which was statistically significant, but there could be other factors influencing this increase.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19920003670','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19920003670"><span id="translatedtitle">Asteroid <span class="hlt">absolute</span> magnitudes and slope parameters</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Tedesco, Edward F.</p> <p>1991-01-01</p> <p>A new listing of <span class="hlt">absolute</span> magnitudes (H) and slope parameters (G) has been created and published in the Minor Planet Circulars; this same listing will appear in the 1992 Ephemerides of Minor Planets. Unlike previous listings, the values of the current list were derived from fits of data at the V band. All observations were reduced in the same fashion using, where appropriate, a single basis default value of 0.15 for the slope parameter. Distances and phase angles were computed for each observation. The data for 113 asteroids was of sufficiently high quality to permit derivation of their H and G. These improved <span class="hlt">absolute</span> magnitudes and slope parameters will be used to deduce the most reliable bias-corrected asteroid size-frequency distribution yet made.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.osti.gov/scitech/biblio/22340250','SCIGOV-STC'); return false;" href="http://www.osti.gov/scitech/biblio/22340250"><span id="translatedtitle"><span class="hlt">Absolute</span>-magnitude distributions of supernovae</span></a></p> <p><a target="_blank" href="http://www.osti.gov/scitech">SciTech Connect</a></p> <p>Richardson, Dean; Wright, John; Jenkins III, Robert L.; Maddox, Larry</p> <p>2014-05-01</p> <p>The <span class="hlt">absolute</span>-magnitude distributions of seven supernova (SN) types are presented. The data used here were primarily taken from the Asiago Supernova Catalogue, but were supplemented with additional data. We accounted for both foreground and host-galaxy extinction. A bootstrap method is used to correct the samples for Malmquist bias. Separately, we generate volume-limited samples, restricted to events within 100 Mpc. We find that the superluminous events (M{sub B} < –21) make up only about 0.1% of all SNe in the bias-corrected sample. The subluminous events (M{sub B} > –15) make up about 3%. The normal Ia distribution was the brightest with a mean <span class="hlt">absolute</span> blue magnitude of –19.25. The IIP distribution was the dimmest at –16.75.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://www.ncbi.nlm.nih.gov/pubmed/21270996','PUBMED'); return false;" href="http://www.ncbi.nlm.nih.gov/pubmed/21270996"><span id="translatedtitle"><span class="hlt">Absolute</span> quantification of transferrin in blood samples of harbour seals using HPLC-ICP-MS.</span></a></p> <p><a target="_blank" href="https://www.ncbi.nlm.nih.gov/entrez/query.fcgi?DB=pubmed">PubMed</a></p> <p>Grebe, Mechthild; Pröfrock, Daniel; Kakuschke, Antje; Broekaert, Jose A C; Prange, Andreas</p> <p>2011-02-01</p> <p>Harbour seals (Phoca vitulina) are bio-indicators for the assessment of their habitat and environmental changes. Besides population parameters and trends (survival, age structure, sex ratio), the individual health status represents a further important parameter for this assessment. The health status of seals is a complex and vague term, determined by a wide range of diagnostic parameters. Quantities of important blood proteins such as transferrin (Tf), as well as altered distribution patterns of its glycoforms, are frequently used as biomarkers in clinical diagnosis. Within this context Tf quantities and a varying pattern of its glycoforms are used as indicator for e.g. certain liver diseases, which also represents one of the most frequently observed pathological indication in harbour seals of the North Sea. Currently, most assay based quantification methods for Tf are limited since they often provide only information regarding the total Tf concentration rather than information of its different glycoforms. Due to a lack of suitable seal Tf antibodies also the application of more specific antibody based approaches is not possible. Within this background a new approach for the <span class="hlt">absolute</span> quantification of the iron-transport protein Tf in the blood of harbour seals using its characteristic iron content and HPLC-ICP-MS detection is described. Method validation was performed using a certified human serum reference material (ERM-DA470K/IFCC). A Tf concentration of 2.33 ± 0.03 g L(-1) (sum of all quantified glycoforms) has been calculated, which is in good agreement with the certified total Tf concentration of 2.35 ± 0.08 g L(-1), confirming the <span class="hlt">accuracy</span> of the proposed analytical method. Finally, different seal samples were analysed to demonstrate the suitability of the procedure for the quantification of Tf in real samples as well as to observe modified glycoform patterns. Compared to our previous studies for the first <span class="hlt">time</span> it was possible to quantify the serum Tf</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://ntrs.nasa.gov/search.jsp?R=19850050574&hterms=VALUE+ABSOLUTE&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DVALUE%2BABSOLUTE','NASA-TRS'); return false;" href="http://ntrs.nasa.gov/search.jsp?R=19850050574&hterms=VALUE+ABSOLUTE&qs=Ntx%3Dmode%2Bmatchall%26Ntk%3DAll%26N%3D0%26No%3D50%26Ntt%3DVALUE%2BABSOLUTE"><span id="translatedtitle"><span class="hlt">Absolute</span> photoionization cross sections of atomic oxygen</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Samson, J. A. R.; Pareek, P. N.</p> <p>1985-01-01</p> <p>The <span class="hlt">absolute</span> values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A. The experimental data is in excellent agreement with rigorous close-coupling calculations that include electron correlations in both the initial and final states.</p> </li> <li> <p><a target="_blank" onclick="trackOutboundLink('http://hdl.handle.net/2060/19840024060','NASA-TRS'); return false;" href="http://hdl.handle.net/2060/19840024060"><span id="translatedtitle"><span class="hlt">Absolute</span> photoionization cross sections of atomic oxygen</span></a></p> <p><a target="_blank" href="http://ntrs.nasa.gov/search.jsp">NASA Technical Reports Server (NTRS)</a></p> <p>Samson, J. A. R.; Pareek, P. N.</p> <p>1982-01-01</p> <p>The <span class="hlt">absolute</span> values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A. The experimental data is in excellent agreement with rigorous close-coupling calculations that include electron correlations in both the initial and final states.</p> </li> </ol> <div class="pull-right"> <ul class="pagination"> <li><a href="#" onclick='return showDiv("page_1");'>«</a></li> <li><a href="#" onclick='return showDiv("page_21");'>21</a></li> <li><a href="#" onclick='return showDiv("page_22");'>22</a></li> <li><a href="#" onclick='return showDiv("page_23");'>23</a></li> <li><a href="#" onclick='return showDiv("page_24");'>24</a></li> <li class="active"><span>25</span></li> <li><a href="#" onclick='return showDiv("page_25");'>»</a></li> </ul> </div> </div><!-- col-sm-12 --> </div><!-- row --> </div><!-- page_25 --> <center> <div class="footer-extlink text-muted"><small>Some links on this page may take you to non-federal websites. 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