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Sample records for absolute error mae

  1. Relative errors can cue absolute visuomotor mappings.

    PubMed

    van Dam, Loes C J; Ernst, Marc O

    2015-12-01

    When repeatedly switching between two visuomotor mappings, e.g. in a reaching or pointing task, adaptation tends to speed up over time. 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 absolute 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 absolute 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 absolute 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 absolute mapping. PMID:26280315

  2. Minimum mean absolute error estimation over the class of generalized stack filters

    NASA Astrophysics Data System (ADS)

    Lin, Jean-Hsang; Coyle, Edward J.

    1990-04-01

    A class of sliding window operators called generalized stack filters is developed. This class of filters, which includes all rank order filters, stack filters, and digital morphological filters, is the set of all filters possessing the threshold decomposition architecture and a consistency property called the stacking property. Conditions under which these filters possess the weak superposition property known as threshold decomposition are determined. An algorithm is provided for determining a generalized stack filter which minimizes the mean absolute error (MAE) between the output of the filter and a desired input signal, given noisy observations of that signal. The algorithm is a linear program whose complexity depends on the window width of the filter and the number of threshold levels observed by each of the filters in the superposition architecture. The results show that choosing the generalized stack filter which minimizes the MAE is equivalent to massively parallel threshold-crossing decision making when the decisions are consistent with each other.

  3. Space Saving Statistics: An Introduction to Constant Error, Variable Error, and Absolute Error.

    ERIC Educational Resources Information Center

    Guth, David

    1990-01-01

    Article discusses research on orientation and mobility (O&M) for individuals with visual impairments, examining constant, variable, and absolute error (descriptive statistics that quantify fundamentally different characteristics of distributions of spatially directed behavior). It illustrates the statistics with examples, noting their application…

  4. Sub-nanometer periodic nonlinearity error in absolute distance interferometers.

    PubMed

    Yang, Hongxing; Huang, Kaiqi; Hu, Pengcheng; Zhu, Pengfei; Tan, Jiubin; Fan, Zhigang

    2015-05-01

    Periodic nonlinearity which can result in error in nanometer scale has become a main problem limiting the absolute distance measurement accuracy. In order to eliminate this error, a new integrated interferometer with non-polarizing beam splitter is developed. This leads to disappearing of the frequency and/or polarization mixing. Furthermore, a strict requirement on the laser source polarization is highly reduced. By combining retro-reflector and angel prism, reference and measuring beams can be spatially separated, and therefore, their optical paths are not overlapped. So, the main cause of the periodic nonlinearity error, i.e., the frequency and/or polarization mixing and leakage of beam, is eliminated. Experimental results indicate that the periodic phase error is kept within 0.0018°. PMID:26026510

  5. On the Error Sources in Absolute Individual Antenna Calibrations

    NASA Astrophysics Data System (ADS)

    Aerts, Wim; Baire, Quentin; Bilich, Andria; Bruyninx, Carine; Legrand, Juliette

    2013-04-01

    field) multi path errors, both during calibration and later on at the station, absolute sub-millimeter positioning with GPS is not (yet) possible. References [1] G. Wübbena, M. Schmitz, G. Boettcher, C. Schumann, "Absolute GNSS Antenna Calibration with a Robot: Repeatability of Phase Variations, Calibration of GLONASS and Determination of Carrier-to-Noise Pattern", International GNSS Service: Analysis Center workshop, 8-12 May 2006, Darmstadt, Germany. [2] P. Zeimetz, H. Kuhlmann, "On the Accuracy of Absolute GNSS Antenna Calibration and the Conception of a New Anechoic Chamber", FIG Working Week 2008, 14-19 June 2008, Stockholm, Sweden. [3] P. Zeimetz, H. Kuhlmann, L. Wanninger, V. Frevert, S. Schön and K. Strauch, "Ringversuch 2009", 7th GNSS-Antennen-Workshop, 19-20 March 2009, Dresden, Germany.

  6. Astigmatism error modification for absolute shape reconstruction using Fourier transform method

    NASA Astrophysics Data System (ADS)

    He, Yuhang; Li, Qiang; Gao, Bo; Liu, Ang; Xu, Kaiyuan; Wei, Xiaohong; Chai, Liqun

    2014-12-01

    A method is proposed to modify astigmatism errors in absolute shape reconstruction of optical plane using Fourier transform method. If a transmission and reflection flat are used in an absolute test, two translation measurements lead to obtain the absolute shapes by making use of the characteristic relationship between the differential and original shapes in spatial frequency domain. However, because the translation device cannot guarantee the test and reference flats rigidly parallel to each other after the translations, a tilt error exists in the obtained differential data, which caused power and astigmatism errors in the reconstructed shapes. In order to modify the astigmatism errors, a rotation measurement is added. Based on the rotation invariability of the form of Zernike polynomial in circular domain, the astigmatism terms are calculated by solving polynomial coefficient equations related to the rotation differential data, and subsequently the astigmatism terms including error are modified. Computer simulation proves the validity of the proposed method.

  7. Comparing Absolute Error with Squared Error for Evaluating Empirical Models of Continuous Variables: Compositions, Implications, and Consequences

    NASA Astrophysics Data System (ADS)

    Gao, J.

    2014-12-01

    Reducing modeling error is often a major concern of empirical geophysical models. However, modeling errors can be defined in different ways: When the response variable is continuous, the most commonly used metrics are squared (SQ) and absolute (ABS) errors. For most applications, ABS error is the more natural, but SQ error is mathematically more tractable, so is often used as a substitute with little scientific justification. Existing literature has not thoroughly investigated the implications of using SQ error in place of ABS error, especially not geospatially. This study compares the two metrics through the lens of bias-variance decomposition (BVD). BVD breaks down the expected modeling error of each model evaluation point into bias (systematic error), variance (model sensitivity), and noise (observation instability). It offers a way to probe the composition of various error metrics. I analytically derived the BVD of ABS error and compared it with the well-known SQ error BVD, and found that not only the two metrics measure the characteristics of the probability distributions of modeling errors differently, but also the effects of these characteristics on the overall expected error are different. Most notably, under SQ error all bias, variance, and noise increase expected error, while under ABS error certain parts of the error components reduce expected error. Since manipulating these subtractive terms is a legitimate way to reduce expected modeling error, SQ error can never capture the complete story embedded in ABS error. I then empirically compared the two metrics with a supervised remote sensing model for mapping surface imperviousness. Pair-wise spatially-explicit comparison for each error component showed that SQ error overstates all error components in comparison to ABS error, especially variance-related terms. Hence, substituting ABS error with SQ error makes model performance appear worse than it actually is, and the analyst would more likely accept a

  8. Absolute plate velocities from seismic anisotropy: Importance of correlated errors

    NASA Astrophysics Data System (ADS)

    Zheng, Lin; Gordon, Richard G.; Kreemer, Corné

    2014-09-01

    The errors in plate motion azimuths inferred from shear wave splitting beneath any one tectonic plate are shown to be correlated with the errors of other azimuths from the same plate. To account for these correlations, we adopt a two-tier analysis: First, find the pole of rotation and confidence limits for each plate individually. Second, solve for the best fit to these poles while constraining relative plate angular velocities to consistency with the MORVEL relative plate angular velocities. Our preferred set of angular velocities, SKS-MORVEL, is determined from the poles from eight plates weighted proportionally to the root-mean-square velocity of each plate. SKS-MORVEL indicates that eight plates (Amur, Antarctica, Caribbean, Eurasia, Lwandle, Somalia, Sundaland, and Yangtze) have angular velocities that differ insignificantly from zero. The net rotation of the lithosphere is 0.25 ± 0.11° Ma-1 (95% confidence limits) right handed about 57.1°S, 68.6°E. The within-plate dispersion of seismic anisotropy for oceanic lithosphere (σ = 19.2°) differs insignificantly from that for continental lithosphere (σ = 21.6°). The between-plate dispersion, however, is significantly smaller for oceanic lithosphere (σ = 7.4°) than for continental lithosphere (σ = 14.7°). Two of the slowest-moving plates, Antarctica (vRMS = 4 mm a-1, σ = 29°) and Eurasia (vRMS = 3 mm a-1, σ = 33°), have two of the largest within-plate dispersions, which may indicate that a plate must move faster than ≈ 5 mm a-1 to result in seismic anisotropy useful for estimating plate motion. The tendency of observed azimuths on the Arabia plate to be counterclockwise of plate motion may provide information about the direction and amplitude of superposed asthenospheric flow or about anisotropy in the lithospheric mantle.

  9. Assessing suturing skills in a self-guided learning setting: absolute symmetry error.

    PubMed

    Brydges, Ryan; Carnahan, Heather; Dubrowski, Adam

    2009-12-01

    Directed self-guidance, whereby trainees independently practice a skill-set in a structured setting, may be an effective technique for novice training. Currently, however, most evaluation methods require an expert to be present during practice. The study aim was to determine if absolute symmetry error, a clinically important measure that can be assessed by the trainee, is a feasible assessment tool for self-guided learning of suturing skill. Forty-eight undergraduate medical trainees independently practiced suturing and knot tying skills using a benchtop model. Performance on a pretest, posttest, retention test and a transfer test was assessed using (1) the validated final product analysis (FPA), (2) the surgical efficiency score (SES), a combination of the FPA and hand motion analysis and (3) absolute symmetry error, a new measure that assesses the symmetry of the final product. Absolute symmetry error, along with the other objective assessment tools, detected improvements in performance from pretest to posttest (P < 0.05). A battery of correlation analyses indicated that absolute symmetry error correlates moderately with the FPA and SES. The development of valid, reliable and feasible technical skill assessments is needed to ensure all training centers evaluate trainee performance in a standardized fashion. Measures that do not require the use of experts or computers have potential for widespread use. We suggest that absolute symmetry error is a useful approximation of novices' suturing and knot tying performance. Future research should evaluate whether absolute symmetry error can enhance learning when used as a source of feedback during self-guided practice. PMID:19132540

  10. Assessing Suturing Skills in a Self-Guided Learning Setting: Absolute Symmetry Error

    ERIC Educational Resources Information Center

    Brydges, Ryan; Carnahan, Heather; Dubrowski, Adam

    2009-01-01

    Directed self-guidance, whereby trainees independently practice a skill-set in a structured setting, may be an effective technique for novice training. Currently, however, most evaluation methods require an expert to be present during practice. The study aim was to determine if absolute symmetry error, a clinically important measure that can be…

  11. IMPROVEMENT OF SMVGEAR II ON VECTOR AND SCALAR MACHINES THROUGH ABSOLUTE ERROR TOLERANCE CONTROL (R823186)

    EPA Science Inventory

    The computer speed of SMVGEAR II was improved markedly on scalar and vector machines with relatively little loss in accuracy. The improvement was due to a method of frequently recalculating the absolute error tolerance instead of keeping it constant for a given set of chemistry. ...

  12. Relative and Absolute Error Control in a Finite-Difference Method Solution of Poisson's Equation

    ERIC Educational Resources Information Center

    Prentice, J. S. C.

    2012-01-01

    An algorithm for error control (absolute and relative) in the five-point finite-difference method applied to Poisson's equation is described. The algorithm is based on discretization of the domain of the problem by means of three rectilinear grids, each of different resolution. We discuss some hardware limitations associated with the algorithm,…

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

    NASA Technical Reports Server (NTRS)

    Thome, Kurtis; McCorkel, Joel; McAndrew, Brendan

    2016-01-01

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

  14. Preliminary error budget for the reflected solar instrument for the Climate Absolute Radiance and Refractivity Observatory

    NASA Astrophysics Data System (ADS)

    Thome, K.; Gubbels, T.; Barnes, R.

    2011-10-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission addresses the need to observe highaccuracy, long-term climate change trends and to use decadal change observations as the most critical method to determine the accuracy of climate change. 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. The instrument suite includes emitted infrared spectrometers, global navigation receivers for radio occultation, and reflected solar spectrometers. The measurements will be acquired for a period of five years and will enable follow-on missions to extend the climate record over the decades needed to understand climate change. This work describes a preliminary error budget for the RS sensor. The RS sensor will retrieve at-sensor reflectance over the spectral range from 320 to 2300 nm with 500-m GIFOV and a 100-km swath width. The current design is based on an Offner spectrometer with two separate focal planes each with its own entrance aperture and grating covering spectral ranges of 320-640, 600-2300 nm. Reflectance is obtained from the ratio of measurements of radiance while viewing the earth's surface to measurements of irradiance while viewing the sun. The requirement for the RS instrument is that the reflectance must be traceable to SI standards at an absolute uncertainty <0.3%. The calibration approach to achieve the ambitious 0.3% absolute calibration uncertainty is predicated on a reliance on heritage hardware, reduction of sensor complexity, and adherence to detector-based calibration standards. The design above has been used to develop a preliminary error budget that meets the 0.3% absolute requirement. Key components in the error budget are geometry differences between the solar and earth views, knowledge of attenuator behavior when viewing the sun, and

  15. Generalized approach for using unbiased symmetric metrics with negative values: normalized mean bias factor and normalized mean absolute error factor

    EPA Science Inventory

    Unbiased symmetric metrics provide a useful measure to quickly compare two datasets, with similar interpretations for both under and overestimations. Two examples include the normalized mean bias factor and normalized mean absolute error factor. However, the original formulations...

  16. Effective connectivity associated with auditory error detection in musicians with absolute pitch

    PubMed Central

    Parkinson, Amy L.; Behroozmand, Roozbeh; Ibrahim, Nadine; Korzyukov, Oleg; Larson, Charles R.; Robin, Donald A.

    2014-01-01

    It is advantageous to study a wide range of vocal abilities in order to fully understand how vocal control measures vary across the full spectrum. Individuals with absolute pitch (AP) are able to assign a verbal label to musical notes and have enhanced abilities in pitch identification without reliance on an external referent. In this study we used dynamic causal modeling (DCM) to model effective connectivity of ERP responses to pitch perturbation in voice auditory feedback in musicians with relative pitch (RP), AP, and non-musician controls. We identified a network compromising left and right hemisphere superior temporal gyrus (STG), primary motor cortex (M1), and premotor cortex (PM). We specified nine models and compared two main factors examining various combinations of STG involvement in feedback pitch error detection/correction process. Our results suggest that modulation of left to right STG connections are important in the identification of self-voice error and sensory motor integration in AP musicians. We also identify reduced connectivity of left hemisphere PM to STG connections in AP and RP groups during the error detection and corrections process relative to non-musicians. We suggest that this suppression may allow for enhanced connectivity relating to pitch identification in the right hemisphere in those with more precise pitch matching abilities. Musicians with enhanced pitch identification abilities likely have an improved auditory error detection and correction system involving connectivity of STG regions. Our findings here also suggest that individuals with AP are more adept at using feedback related to pitch from the right hemisphere. PMID:24634644

  17. Preliminary Error Budget for the Reflected Solar Instrument for the Climate Absolute Radiance and Refractivity Observatory

    NASA Technical Reports Server (NTRS)

    Thome, Kurtis; Gubbels, Timothy; Barnes, Robert

    2011-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) plans to observe climate change trends over decadal time scales to determine the accuracy 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 absolute solar irradiance measurements. The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission addresses the need to observe high-accuracy, long-term climate change trends and to use decadal change observations as the most critical method to determine the accuracy of climate change projections such as those in the IPCC Report. A rigorously known accuracy 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

  18. Error budget for a calibration demonstration system for the reflected solar instrument for the climate absolute radiance and refractivity observatory

    NASA Astrophysics Data System (ADS)

    Thome, Kurtis; McCorkel, Joel; McAndrew, Brendan

    2013-09-01

    A goal of the Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission is to observe highaccuracy, long-term climate change trends over decadal time scales. The key to such a goal is to improving the accuracy of SI traceable absolute 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 absolute accuracy 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 Absolute 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, absolute 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.

  19. Error Budget for a Calibration Demonstration System for the Reflected Solar Instrument for the Climate Absolute Radiance and Refractivity Observatory

    NASA Technical Reports Server (NTRS)

    Thome, Kurtis; McCorkel, Joel; McAndrew, Brendan

    2013-01-01

    A goal of the Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission is to observe highaccuracy, long-term climate change trends over decadal time scales. The key to such a goal is to improving the accuracy of SI traceable absolute 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 absolute accuracy 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 Absolute 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, absolute 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.

  20. Generalized approach for using unbiased symmetric metrics with negative values: normalized mean bias factor and normalized mean absolute error factor

    SciTech Connect

    Gustafson, William I.; Yu, Shaocai

    2012-10-23

    Unbiased symmetric metrics provide a useful measure to quickly compare two datasets, with similar interpretations for both under and overestimations. Two examples include the normalized mean bias factor and normalized mean absolute error factor. However, the original formulations of these metrics are only valid for datasets with positive means. This paper presents a methodology to use and interpret the metrics with datasets that have negative means. The updated formulations give identical results compared to the original formulations for the case of positive means, so researchers are encouraged to use the updated formulations going forward without introducing ambiguity.

  1. Sallie Mae Eyes Expansion beyond Its Charter.

    ERIC Educational Resources Information Center

    Zook, Jim

    1995-01-01

    The Student Loan Marketing Association (Sallie Mae) and the Clinton Administration are preparing legislation to transform the federally sponsored corporation into a private business but must negotiate complex political and financial issues. Destabilization of the private student-loan industry and conflict over direct-lending policies are central…

  2. Left-hemisphere activation is associated with enhanced vocal pitch error detection in musicians with absolute pitch

    PubMed Central

    Behroozmand, Roozbeh; Ibrahim, Nadine; Korzyukov, Oleg; Robin, Donald A.; Larson, Charles R.

    2014-01-01

    The ability to process auditory feedback for vocal pitch control is crucial during speaking and singing. Previous studies have suggested that musicians with absolute pitch (AP) develop specialized left-hemisphere mechanisms for pitch processing. The present study adopted an auditory feedback pitch perturbation paradigm combined with ERP recordings to test the hypothesis whether the neural mechanisms of the left-hemisphere enhance vocal pitch error detection and control in AP musicians compared with relative pitch (RP) musicians and non-musicians (NM). Results showed a stronger N1 response to pitch-shifted voice feedback in the right-hemisphere for both AP and RP musicians compared with the NM group. However, the left-hemisphere P2 component activation was greater in AP and RP musicians compared with NMs and also for the AP compared with RP musicians. The NM group was slower in generating compensatory vocal reactions to feedback pitch perturbation compared with musicians, and they failed to re-adjust their vocal pitch after the feedback perturbation was removed. These findings suggest that in the earlier stages of cortical neural processing, the right hemisphere is more active in musicians for detecting pitch changes in voice feedback. In the later stages, the left-hemisphere is more active during the processing of auditory feedback for vocal motor control and seems to involve specialized mechanisms that facilitate pitch processing in the AP compared with RP musicians. These findings indicate that the left hemisphere mechanisms of AP ability are associated with improved auditory feedback pitch processing during vocal pitch control in tasks such as speaking or singing. PMID:24355545

  3. 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…

  4. dbMAE: the database of autosomal monoallelic expression

    PubMed Central

    Savova, Virginia; Patsenker, Jon; Vigneau, Sébastien; Gimelbrant, Alexander A.

    2016-01-01

    Recently, data on ‘random’ autosomal monoallelic expression has become available for the entire genome in multiple human and mouse tissues and cell types, creating a need for better access and dissemination. The database of autosomal monoallelic expression (dbMAE; https://mae.hms.harvard.edu) incorporates data from multiple recent reports of genome-wide analyses. These include transcriptome-wide analyses of allelic imbalance in clonal cell populations based on sequence polymorphisms, as well as indirect identification, based on a specific chromatin signature present in MAE gene bodies. Currently, dbMAE contains transcriptome-wide chromatin identification calls for 8 human and 21 mouse tissues, and describes over 16 000 murine and ∼700 human cases of directly measured biased expression, compiled from allele-specific RNA-seq and genotyping array data. All data are manually curated. To ensure cross-publication uniformity, we performed re-analysis of transcriptome-wide RNA-seq data using the same pipeline. Data are accessed through an interface that allows for basic and advanced searches; all source references, including raw data, are clearly described and hyperlinked. This ensures the utility of the resource as an initial screening tool for those interested in investigating the role of monoallelic expression in their specific genes and tissues of interest. PMID:26503248

  5. Temperature Variability Associated with the Middle Atmosphere Electrodynamics (MAE-1) Campaign

    NASA Technical Reports Server (NTRS)

    Schmidlin, F. J.

    1999-01-01

    Meteorological rockets launched during the Middle Atmosphere Electrodynamics (MAE-1) Campaign in October 1980 from Andoya Rocket Range (ARR), Norway, exhibited large and unexpected temperature variability. Temperatures were found to vary as much as 20 C within a few hours and demonstrated a similar type of variability from one day to the next. Following examination of the reduced rocketsonde profiles the question was raised whether the observed variability was due to natural atmospheric variability or instrument malfunction. Small-scale variability, as observed, may result from one or multiple sources, e.g., intense storms upstream from the observing site, orography such as mountain waves off of the Greenland Plateau, convective activity, gravity waves, etc. Arranging the observations spaced over time showed that the perturbations moved downward. Prior to MAE-1 very few small rocketsonde measurements had been launched from ARR, thus the quality of the initial measurements in early October caused concern when the large variability was noted. We discuss the errors of the rocketsonde measurements, graphically review the nature of the variability observed, compare the data with other measurements, and postulate a possible cause for the variability.

  6. The effect of a safe zone on nurse interruptions, distractions, and medication administration errors.

    PubMed

    Yoder, Mindy; Schadewald, Diane; Dietrich, Kim

    2015-01-01

    Patient safety is a health care priority. Yet medical errors are ranked the eighth leading cause of death. Medication administration errors (MAEs) often result from multiple environmental and individual factors. This quality improvement initiative adapted a protocol based on airline industry safety measures to decrease nurse distractions and interruptions during medication administration, with the goal of decreasing MAEs. Sources of distractions, interruptions, and MAEs were measured pre and post intervention. Patient satisfaction scores were measured concurrently. Results of this initiative differ from previous studies in which similar interventions reduced both distractions and MAEs. An unexpected finding was dramatically increased patient satisfaction. PMID:25723837

  7. 31 CFR 354.7 - Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Sallie Mae Securities for conversion to definitive form. 354.7 Section 354.7 Money and Finance: Treasury... (SALLIE MAE) § 354.7 Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form. (a) Eligible Book-entry Sallie Mae Securities may be withdrawn from the Book-entry System...

  8. 31 CFR 354.7 - Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Sallie Mae Securities for conversion to definitive form. 354.7 Section 354.7 Money and Finance: Treasury... MAE) § 354.7 Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form. (a) Eligible Book-entry Sallie Mae Securities may be withdrawn from the Book-entry System...

  9. 31 CFR 354.7 - Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Sallie Mae Securities for conversion to definitive form. 354.7 Section 354.7 Money and Finance: Treasury... MAE) § 354.7 Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form. (a) Eligible Book-entry Sallie Mae Securities may be withdrawn from the Book-entry System...

  10. 31 CFR 354.7 - Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Sallie Mae Securities for conversion to definitive form. 354.7 Section 354.7 Money and Finance: Treasury... MAE) § 354.7 Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form. (a) Eligible Book-entry Sallie Mae Securities may be withdrawn from the Book-entry System...

  11. 31 CFR 354.7 - Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Sallie Mae Securities for conversion to definitive form. 354.7 Section 354.7 Money and Finance: Treasury... MAE) § 354.7 Withdrawal of eligible Book-entry Sallie Mae Securities for conversion to definitive form. (a) Eligible Book-entry Sallie Mae Securities may be withdrawn from the Book-entry System...

  12. Despite a Settlement, Sallie Mae Still Plays Host to College Student-Aid Sites

    ERIC Educational Resources Information Center

    Hermes, J. J.

    2008-01-01

    Last April, as part of a $2-million settlement with New York's attorney general, the nation's largest student-loan company, Sallie Mae, agreed to stop providing staff members for colleges' financial-aid offices and call centers at no cost to the institutions. But one year later, Sallie Mae still plays host to the entire online presence for the…

  13. 31 CFR 354.0 - Applicability; maintenance of Sallie Mae Securities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 2 2010-07-01 2010-07-01 false Applicability; maintenance of Sallie Mae Securities. 354.0 Section 354.0 Money and Finance: Treasury Regulations Relating to Money and... GOVERNING BOOK-ENTRY SECURITIES OF THE STUDENT LOAN MARKETING ASSOCIATION (SALLIE MAE) § 354.0...

  14. Absolute Zero

    NASA Astrophysics Data System (ADS)

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

    2006-12-01

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

  15. 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. .

  16. 78 FR 21393 - Notice of Submission of Proposed Information Collection to OMB Ginnie Mae Multiclass Securities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ... (``REMIC'') securities, Stripped Mortgage-Backed Securities (``SMBS''), and Platinum securities. The... timely payment of principal and interest on Ginnie Mae REMIC, SMBS and Platinum securities. DATES...'') securities, Stripped Mortgage- Backed Securities (``SMBS''), and Platinum securities. The...

  17. The Precise Observation System for the Safe Use of Medicines (POSSUM): An Approach for Studying Medication Administration Errors in the Field.

    PubMed

    Westbrook, Johanna I; Raban, Magdalena Z; Lehnbom, Elin C; Li, Ling

    2016-01-01

    Medication administration errors (MAEs) in hospital are frequent and significantly more likely to result in serious harm to patients than other medication error types. Many interventions have been proposed in order reduce MAEs and the amount of harm associated with these errors. A major limitation in assessing the effectiveness of these interventions has been the lack of robust measures for assessing changes in MAEs and associated harms. Drawing upon extensive foundational research we have developed a robust approach and data collection software to be applied in direct observational studies of nurses to allow measurement of changes in MAE rates. We report how this approach is being applied in a large stepped-wedge cluster randomised controlled trial to assess the effectiveness of an electronic medication management system to reduce MAEs in a paediatric hospital. PMID:27577460

  18. Absolute calibration of optical flats

    DOEpatents

    Sommargren, Gary E.

    2005-04-05

    The invention uses the phase shifting diffraction interferometer (PSDI) to provide a true point-by-point measurement of absolute 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 absolute phase error of the optical flat is obtained.

  19. 24 CFR 350.8 - Withdrawal of Eligible Book-entry Ginnie Mae Securities for Conversion to Definitive Form.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... book-entry in the Book-entry System, facilitate the conversion of such securities into Definitive... Ginnie Mae Securities for Conversion to Definitive Form. 350.8 Section 350.8 Housing and Urban... Book-entry Ginnie Mae Securities for Conversion to Definitive Form. (a) Eligible book-entry Ginnie...

  20. 24 CFR 350.8 - Withdrawal of Eligible Book-entry Ginnie Mae Securities for Conversion to Definitive Form.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... book-entry in the Book-entry System, facilitate the conversion of such securities into Definitive... Ginnie Mae Securities for Conversion to Definitive Form. 350.8 Section 350.8 Housing and Urban... Book-entry Ginnie Mae Securities for Conversion to Definitive Form. (a) Eligible book-entry Ginnie...

  1. 24 CFR 350.8 - Withdrawal of Eligible Book-entry Ginnie Mae Securities for Conversion to Definitive Form.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... book-entry in the Book-entry System, facilitate the conversion of such securities into Definitive... Ginnie Mae Securities for Conversion to Definitive Form. 350.8 Section 350.8 Housing and Urban... Book-entry Ginnie Mae Securities for Conversion to Definitive Form. (a) Eligible book-entry Ginnie...

  2. 24 CFR 350.8 - Withdrawal of Eligible Book-entry Ginnie Mae Securities for Conversion to Definitive Form.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... book-entry in the Book-entry System, facilitate the conversion of such securities into Definitive... Ginnie Mae Securities for Conversion to Definitive Form. 350.8 Section 350.8 Housing and Urban... Book-entry Ginnie Mae Securities for Conversion to Definitive Form. (a) Eligible book-entry Ginnie...

  3. 24 CFR 350.8 - Withdrawal of Eligible Book-entry Ginnie Mae Securities for Conversion to Definitive Form.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... book-entry in the Book-entry System, facilitate the conversion of such securities into Definitive... Ginnie Mae Securities for Conversion to Definitive Form. 350.8 Section 350.8 Housing and Urban... Book-entry Ginnie Mae Securities for Conversion to Definitive Form. (a) Eligible book-entry Ginnie...

  4. How America Pays for College, 2011. Sallie Mae's National Study of College Students and Parents

    ERIC Educational Resources Information Center

    Sallie Mae, Inc., 2011

    2011-01-01

    Sallie Mae's national study, "How America Pays for College," now in its fourth year, shows the resilience of American families' strongly held belief in the value of a college education. Even in the face of rising tuition costs and the worst economic decline in a generation, between academic years 2007-2008 and 2009-2010 Americans paid increasingly…

  5. 78 FR 23281 - Notice of Proposed Information Collection; Comment Request: Ginnie Mae Multiclass Securities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-18

    ...-Backed Securities (``SMBS''), and Platinum securities. The Multiclass Securities program provides an... Ginnie Mae REMIC, SMBS and Platinum securities. Agency form numbers, if applicable: Not applicable.... Subtotal 232.5 ......... 995.3 Platinum Securities: Deposit Agreement......... Depositor....... 19 10 190...

  6. 77 FR 71433 - Notice of Proposed Information Collection: Comment Request; Ginnie Mae Multiclass Securities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-30

    ...-Backed Securities (``SMBS''), and Platinum securities. The Multiclass Securities program provides an... Ginnie Mae REMIC, SMBS and Platinum securities. Agency form numbers, if applicable: Not applicable........... 10 1 10 2 20 Total 232.5 995.3 Platinum Securities Deposit Agreement Depositor 19 10 190 1 190...

  7. 75 FR 5336 - Notice of Proposed Information Collection: Comment Request; Ginnie Mae Multiclass Securities...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-02

    ... Mortgage-Backed Securities (``SMBS''), and Platinum securities. The Multiclass Securities program provides... on Ginnie Mae REMIC, SMBS and Platinum securities. Agency form numbers, if applicable: Not applicable... for Sponsor........ 10 1 10 2 20 Total 232.5 995.3 Platinum Securities Deposit Agreement Depositor...

  8. How America Pays for College, 2012. Sallie Mae's National Study of College Students and Parents

    ERIC Educational Resources Information Center

    Sallie Mae, Inc., 2012

    2012-01-01

    Sallie Mae has conducted "How America Pays for College" annually since 2008, providing information about the resources American families invest in an undergraduate college education. This study focuses particularly on the planning and payment behaviors in a given academic year. Now in its fifth year, the study allows tracking over time of changes…

  9. How America Pays for College, 2009. Sallie Mae's National Study of College Students and Parents

    ERIC Educational Resources Information Center

    Sallie Mae, Inc., 2009

    2009-01-01

    Sallie Mae's study, "How America Pays for College 2009," conducted by Gallup, provides a picture of how families made the investment in higher education last academic year and how they are beginning to meet the challenges of the economic recession. Based on a nationally representative survey of college-going students and parents of undergraduates,…

  10. How America Pays for College, 2014: Sallie Mae's National Study of College Students and Parents

    ERIC Educational Resources Information Center

    Sallie Mae, Inc., 2014

    2014-01-01

    Sallie Mae has conducted "How America Pays for College" annually since 2008, providing information about the resources American families invest in an undergraduate college education. This study focuses particularly on the planning and payment behaviors in a given academic year. Now in its seventh year, the study provides a compelling…

  11. The Miocene avifauna of the Li Mae Long locality, Thailand: systematics and paleoecology

    NASA Astrophysics Data System (ADS)

    Cheneval, Jacques; Ginsburg, Léonard; Mourer-Chauvire, Cécile; Ratanasthien, Benjavun

    The Miocene avifauna from Li Mae Long includes an anhinga, a heron, a new species of lesser flamingo, Phoeniconaias siamensis n. sp., two Anatidae, a Phasianidae, three Rallidae, and a Strigidae. The landscape indicated by the mammalian and avian faunas corresponds to a large swampy depression, with probably saline or alkaline waters, surrounded by humid forests, under a warm climate.

  12. African-American Soul Force: Dance, Music and Vera Mae Green.

    ERIC Educational Resources Information Center

    Bolles, A. Lynn

    1986-01-01

    The Black anthropologist, Vera Mae Green, is featured in this analysis of the concept of soul as applied to African-Americans. Music and dance are used to express soul in cultural context. But soul is also a force, an energy which encompasses the Black experience and makes Black culture persevere. (VM)

  13. 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…

  14. Palynology and organic/isotope geochemistry of the Mae Moh Basin, Northern Thailand

    SciTech Connect

    Minh, L.V.; Abrajano, T.; Burden, E.; Winsor, L. ); Ratanasthien, B. )

    1994-07-01

    The Mae Moh basin is one of several Tertiary intermontane basins in northern Thailand, whose evolution has been linked to the collision of the Indian plate with the Eurasian plate since the early Eocene. As in most of these basins, lacustrine/swamp sedimentation in the Mae Moh basin can be broadly divided into an Oligocene to Miocene synrift sequence and a Miocene to Quarternary postrift sequence. The dominance of swamp flora recognized from spore and pollen assemblages (e.g., Polypodiidites usmensis, Verrucatosporites, Cyrtostachys), as well as the abundance of macrophytes and woody debris, indicate overwhelming hot and humid swamp conditions, with lake development restricted to relatively small areas. The distribution of alkanes and their compound-specific carbon isotope compositions are used to further show climatic variations affecting the lake/swamp ecology during the deposition of the synrift sequence.

  15. Correction of a Technical Error in the Golf Swing: Error Amplification Versus Direct Instruction.

    PubMed

    Milanese, Chiara; Corte, Stefano; Salvetti, Luca; Cavedon, Valentina; Agostini, Tiziano

    2016-01-01

    Performance errors drive motor learning for many tasks. The authors' aim was to determine which of two strategies, method of amplification of error (MAE) or direct instruction (DI), would be more beneficial for error correction during a full golfing swing with a driver. Thirty-four golfers were randomly assigned to one of three training conditions (MAE, DI, and control). Participants were tested in a practice session in which each golfer performed 7 pretraining trials, 6 training-intervention trials, and 7 posttraining trials; and a retention test after 1 week. An optoeletronic motion capture system was used to measure the kinematic parameters of each golfer's performance. Results showed that MAE is an effective strategy for correcting the technical errors leading to a rapid improvement in performance. These findings could have practical implications for sport psychology and physical education because, while practice is obviously necessary for improving learning, the efficacy of the learning process is essential in enhancing learners' motivation and sport enjoyment. PMID:27159565

  16. [Aquatic Ecological Index based on freshwater (ICE(RN-MAE)) for the Rio Negro watershed, Colombia].

    PubMed

    Forero, Laura Cristina; Longo, Magnolia; John Jairo, Ramirez; Guillermo, Chalar

    2014-04-01

    Aquatic Ecological Index based on freshwater (ICE(RN-MAE)) for the Rio Negro watershed, Colombia. Available indices to assess the ecological status of rivers in Colombia are mostly based on subjective hypotheses about macroinvertebrate tolerance to pollution, which have important limitations. Here we present the application of a method to establish an index of ecological quality for lotic systems in Colombia. The index, based on macroinvertebrate abundance and physicochemical variables, was developed as an alternative to the BMWP-Col index. The method consists on determining an environmental gradient from correlations between physicochemical variables and abundance. The scores obtained in each sampling point are used in a standardized correlation for a model of weighted averages (WA). In the WA model abundances are also weighted to estimate the optimum and tolerance values of each taxon; using this information we estimated the index of ecological quality based also on macroinvertebrate (ICE(RN-MAE)) abundance in each sampling site. Subsequently, we classified all sites using the index and concentrations of total phosphorus (TP) in a cluster analysis. Using TP and ICE(RN-MAE), mean, maximum, minimum and standard deviation, we defined threshold values corresponding to three categories of ecological status: good, fair and critical. PMID:25189081

  17. MAE4, an eLtaS monoclonal antibody, blocks Staphylococcus aureus virulence

    PubMed Central

    Liu, Yu; Feng, Jiannan; Lu, Qiang; Zhang, Xin; Gao, Yaping; Yan, Jun; Mu, Chunhua; Hei, Yan; Lv, Ming; Han, Gencheng; Chen, Guojiang; Jin, Peng; Hu, Weiguo; Shen, Beifen; Yang, Guang

    2015-01-01

    Staphylococcus aureus causes a wide range of infectious diseases. Treatment of these infections has become increasingly difficult due to the widespread emergence of antibiotic-resistant strains; therefore, it is essential to explore effective alternatives to antibiotics. A secreted protein of S. aureus, known as eLtaS, is an extracellular protein released from the bacterial membrane protein, LtaS. However, the role of eLtaS in S. aureus pathogenesis remains largely unknown. Here we show eLtaS dramatically aggravates S. aureus infection by binding to C3b and then inhibiting the phagocytosis of C3b-deposited S. aureus. Furthermore, we developed a monoclonal antibody against eLtaS, MAE4, which neutralizes the activity of eLtaS and blocks staphylococcal evasion of phagocytosis. Consequently, MAE4 is capable of protecting mice from lethal S. aureus infection. Our findings reveal that targeting of eLtaS by MAE4 is a potential therapeutic strategy for the treatment of infectious diseases caused by S. aureus. PMID:26599734

  18. Eosinophil count - absolute

    MedlinePlus

    Eosinophils; Absolute eosinophil count ... the white blood cell count to give the absolute eosinophil count. ... than 500 cells per microliter (cells/mcL). Normal value ranges may vary slightly among different laboratories. Talk ...

  19. Improving HST Pointing & Absolute Astrometry

    NASA Astrophysics Data System (ADS)

    Lallo, Matthew; Nelan, E.; Kimmer, E.; Cox, C.; Casertano, S.

    2007-05-01

    Accurate absolute astrometry is becoming increasingly important in an era of multi-mission archives and virtual observatories. Hubble Space Telescope's (HST's) Guidestar Catalog II (GSC2) has reduced coordinate error to around 0.25 arcsecond, a factor 2 or more compared with GSC1. With this reduced catalog error, special attention must be given to calibrate and maintain the Fine Guidance Sensors (FGSs) and Science Instruments (SIs) alignments in HST to a level well below this in order to ensure that the accuracy of science product's astrometry keywords and target positioning are limited only by the catalog errors. After HST Servicing Mission 4, such calibrations' improvement in "blind" pointing accuracy will allow for more efficient COS acquisitions. Multiple SIs and FGSs each have their own footprints in the spatially shared HST focal plane. It is the small changes over time in primarily the whole-body positions & orientations of these instruments & guiders relative to one another that is addressed by this work. We describe the HST Cycle 15 program CAL/OTA 11021 which, along with future variants of it, determines and maintains positions and orientations of the SIs and FGSs to better than 50 milli- arcseconds and 0.04 to 0.004 degrees of roll, putting errors associated with the alignment sufficiently below GSC2 errors. We present recent alignment results and assess their errors, illustrate trends, and describe where and how the observer sees benefit from these calibrations when using HST.

  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. Quality improvements in decreasing medication administration errors made by nursing staff in an academic medical center hospital: a trend analysis during the journey to Joint Commission International accreditation and in the post-accreditation era

    PubMed Central

    Wang, Hua-fen; Jin, Jing-fen; Feng, Xiu-qin; Huang, Xin; Zhu, Ling-ling; Zhao, Xiao-ying; Zhou, Quan

    2015-01-01

    Background Medication errors may occur during prescribing, transcribing, prescription auditing, preparing, dispensing, administration, and monitoring. Medication administration errors (MAEs) are those that actually reach patients and remain a threat to patient safety. The Joint Commission International (JCI) advocates medication error prevention, but experience in reducing MAEs during the period of before and after JCI accreditation has not been reported. Methods An intervention study, aimed at reducing MAEs in hospitalized patients, was performed in the Second Affiliated Hospital of Zhejiang University, Hangzhou, People’s Republic of China, during the journey to JCI accreditation and in the post-JCI accreditation era (first half-year of 2011 to first half-year of 2014). Comprehensive interventions included organizational, information technology, educational, and process optimization-based measures. Data mining was performed on MAEs derived from a compulsory electronic reporting system. Results The number of MAEs continuously decreased from 143 (first half-year of 2012) to 64 (first half-year of 2014), with a decrease in occurrence rate by 60.9% (0.338% versus 0.132%, P<0.05). The number of MAEs related to high-alert medications decreased from 32 (the second half-year of 2011) to 16 (the first half-year of 2014), with a decrease in occurrence rate by 57.9% (0.0787% versus 0.0331%, P<0.05). Omission was the top type of MAE during the first half-year of 2011 to the first half-year of 2014, with a decrease by 50% (40 cases versus 20 cases). Intravenous administration error was the top type of error regarding administration route, but it continuously decreased from 64 (first half-year of 2012) to 27 (first half-year of 2014). More experienced registered nurses made fewer medication errors. The number of MAEs in surgical wards was twice that in medicinal wards. Compared with non-intensive care units, the intensive care units exhibited higher occurrence rates of MAEs

  3. Requirement of the Lactobacillus casei MaeKR two-component system for L-malic acid utilization via a malic enzyme pathway.

    PubMed

    Landete, José María; García-Haro, Luisa; Blasco, Amalia; Manzanares, Paloma; Berbegal, Carmen; Monedero, Vicente; Zúñiga, Manuel

    2010-01-01

    Lactobacillus casei can metabolize L-malic acid via malolactic enzyme (malolactic fermentation [MLF]) or malic enzyme (ME). Whereas utilization of L-malic acid via MLF does not support growth, the ME pathway enables L. casei to grow on L-malic acid. In this work, we have identified in the genomes of L. casei strains BL23 and ATCC 334 a cluster consisting of two diverging operons, maePE and maeKR, encoding a putative malate transporter (maeP), an ME (maeE), and a two-component (TC) system belonging to the citrate family (maeK and maeR). Homologous clusters were identified in Enterococcus faecalis, Streptococcus agalactiae, Streptococcus pyogenes, and Streptococcus uberis. Our results show that ME is essential for L-malic acid utilization in L. casei. Furthermore, deletion of either the gene encoding the histidine kinase or the response regulator of the TC system resulted in the loss of the ability to grow on L-malic acid, thus indicating that the cognate TC system regulates and is essential for the expression of ME. Transcriptional analyses showed that expression of maeE is induced in the presence of L-malic acid and repressed by glucose, whereas TC system expression was induced by L-malic acid and was not repressed by glucose. DNase I footprinting analysis showed that MaeR binds specifically to a set of direct repeats [5'-TTATT(A/T)AA-3'] in the mae promoter region. The location of the repeats strongly suggests that MaeR activates the expression of the diverging operons maePE and maeKR where the first one is also subjected to carbon catabolite repression. PMID:19897756

  4. UAE, MAE, SFE-CO2 and classical methods for the extraction of Mitragyna speciosa leaves.

    PubMed

    Orio, Laura; Alexandru, Lavinia; Cravotto, Giancarlo; Mantegna, Stefano; Barge, Alessandro

    2012-05-01

    Mitragyna speciosa, a tropical plant indigenous to Southeast Asia, is well known for its psychoactive properties. Its leaves are traditionally chewed by Thai and Malaysian farmers and manual labourers as it causes a numbing, stimulating effect. The present study aims to evaluate alkaloid yield and composition in the leaf extracts. For this purpose we have compared several non-conventional extraction techniques with classic procedures (room temperature or under heating). Dried M. speciosa leaves belonging to three batches of different origin (from Thailand, Malaysia and Indonesia) were extracted using ultrasound-assisted extraction (UAE), microwave-assisted extraction (MAE) and supercritical carbon dioxide extraction SFE-CO(2), using methanol, ethanol, water and binary mixtures. The extracts were compared using an HPLC/ESI-MS analysis of mitragynine and four other related alkaloids which were present in the alkaloid fraction. The extraction technique influences both the raw product yield and the relative alkaloid content of M. speciosa leaves. Of the several methods tested, MAE in a closed vessel at 110 °C (60 W, methanol/water 1:1) gave the highest alkaloid fraction amount, while UAE with an immersion horn at 25 °C (21.4 kHz, 50 W, methanol) showed the best yield for mitragynine. This work may prove to be a useful contribution to forensic, toxicological and pharmacognosy studies. Although the potential applications of M. speciosa alkaloids clearly need further investigation, these results may facilitate the scaling-up of their extraction. PMID:22054912

  5. Measuring teachers' knowledge of attention deficit hyperactivity disorder: the MAE-TDAH Questionnaire.

    PubMed

    Soroa, Marian; Balluerka, Nekane; Gorostiaga, Arantxa

    2014-01-01

    The lack of methodological rigor is frequent in most of instruments developed to assess the knowledge of teachers regarding Attention Deficit Hyperactivity Disorder (ADHD). The aim of this study was to develop a questionnaire, namely Questionnaire for the evaluation of teachers' knowledge of ADHD (MAE-TDAH), for measuring the level of knowledge about ADHD of infant and primary school teachers. A random sample of 526 teachers from 57 schools in the Autonomous Community of the Basque Country and Navarre was used for the analysis of the psychometric properties of the instrument. The participant teachers age range was between 22 and 65 (M = 42.59; SD = 10.89), and there were both generalist and specialized teachers. The measure showed a 4 factor structure (Etiology of ADHD, Symptoms/Diagnosis of ADHD, General information about ADHD and Treatment of ADHD) with adequate internal consistency (Omega values ranged between .83 and .91) and temporal stability indices (Spearman's Rho correlation values ranged between .62 and .79). Furthermore, evidence of convergent and external validity was obtained. Results suggest that the MAE-TDAH is a valid and reliable measure when it comes to evaluating teachers' level of knowledge of ADHD. PMID:26055541

  6. Experiments on the applicability of MAE techniques for predicting sound diffraction by irregular terrains. [Matched Asymptotic Expansion

    NASA Technical Reports Server (NTRS)

    Berthelot, Yves H.; Pierce, Allan D.; Kearns, James A.

    1987-01-01

    The sound field diffracted by a single smooth hill of finite impedance is studied both analytically, within the context of the theory of Matched Asymptotic Expansions (MAE), and experimentally, under laboratory scale modeling conditions. Special attention is given to the sound field on the diffracting surface and throughout the transition region between the illuminated and the shadow zones. The MAE theory yields integral equations that are amenable to numerical computations. Experimental results are obtained with a spark source producing a pulse of 42 microsec duration and about 130 Pa at 1 m. The insertion loss of the hill is inferred from measurements of the acoustic signals at two locations in the field, with subsequent Fourier analysis on an IBM PC/AT. In general, experimental results support the predictions of the MAE theory, and provide a basis for the analysis of more complicated geometries.

  7. Absolute biological needs.

    PubMed

    McLeod, Stephen

    2014-07-01

    Absolute 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 absolute needs on the grounds that the verb 'need' has instrumental and absolute senses. While remaining neutral about it, this article does not adopt that approach. Instead, it suggests that there are absolute biological needs. The absolute 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 absolute need is not inherently normative in either of the first two senses. PMID:23586876

  8. Late Devonian sedimentary record of the Paleotethys Ocean - The Mae Sariang section, northwestern Thailand

    NASA Astrophysics Data System (ADS)

    Königshof, P.; Savage, N. M.; Lutat, P.; Sardsud, A.; Dopieralska, J.; Belka, Z.; Racki, G.

    2012-06-01

    An 11 m thick condensed sequence of Late Devonian limestones in northwestern Thailand exhibits faunal associations and sedimentological-/microfacies data which are indicative of a pelagic facies setting. The entire long-ranging section is completely free from clastic input. Similar successions are known worldwide in a few sections only. The Mae Sariang section is characterised by low sedimentation rates as recognised by a number of hardgrounds, neptunian dikes and Fe/Mn crusts. The succession comprises a number of pelagic faunal elements e.g. conodonts, cephalopods and pelagic ostracodes. The fauna records rare macrofossils and the faunal diversity is low. The very condensed section ranges from the Late rhenana to praesulcata conodont biozones, but contains some global events as undoubtedly shown by biostratigraphical and carbon-isotope results (including major Kellwasser and Hangenberg biotic crises). In terms of plate tectonics this important succession most probably belongs to the Inthanon Zone comprising remnants of the Paleotethys Ocean.

  9. 24 CFR 350.11 - Notice of Attachment for Ginnie Mae Securities in Book-entry System.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Securities in Book-entry System. 350.11 Section 350.11 Housing and Urban Development Regulations Relating to... AND URBAN DEVELOPMENT BOOK-ENTRY PROCEDURES § 350.11 Notice of Attachment for Ginnie Mae Securities in Book-entry System. The interest of a debtor in a Security Entitlement may be reached by a creditor...

  10. How America Saves for College, 2013. Sallie Mae's National Study of Parents with Children under Age 18

    ERIC Educational Resources Information Center

    Sallie Mae, Inc., 2013

    2013-01-01

    Sallie Mae has conducted an ongoing study, "How America Pays for College," annually since 2008. Through that study, the researchers are able to provide a clearer picture of how the typical American undergraduate is paying for college today. This report is the third in the "How America Saves for College" series conducted since 2009. Interviews took…

  11. 24 CFR 350.11 - Notice of Attachment for Ginnie Mae Securities in Book-entry System.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Securities in Book-entry System. 350.11 Section 350.11 Housing and Urban Development Regulations Relating to... AND URBAN DEVELOPMENT BOOK-ENTRY PROCEDURES § 350.11 Notice of Attachment for Ginnie Mae Securities in Book-entry System. The interest of a debtor in a Security Entitlement may be reached by a creditor...

  12. 24 CFR 350.11 - Notice of Attachment for Ginnie Mae Securities in Book-entry System.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Securities in Book-entry System. 350.11 Section 350.11 Housing and Urban Development Regulations Relating to... AND URBAN DEVELOPMENT BOOK-ENTRY PROCEDURES § 350.11 Notice of Attachment for Ginnie Mae Securities in Book-entry System. The interest of a debtor in a Security Entitlement may be reached by a creditor...

  13. How America Saves for College, 2014: Sallie Mae's National Study of Parents with Children under Age 18

    ERIC Educational Resources Information Center

    Sallie Mae, Inc., 2014

    2014-01-01

    This is the fourth report in the Sallie Mae series "How America Saves for College," which launched in 2009. To understand how American families are planning for their children's education, the study captures data on parents' decision-making about savings, the use of savings vehicles, and the amount they save, as well as attitudes toward…

  14. The absolute path command

    2012-05-11

    The ap command traveres all symlinks in a given file, directory, or executable name to identify the final absolute 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 absolute path to a relative directory from the current working directory.« less

  15. The absolute path command

    SciTech Connect

    Moody, A.

    2012-05-11

    The ap command traveres all symlinks in a given file, directory, or executable name to identify the final absolute 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 absolute path to a relative directory from the current working directory.

  16. 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

  17. Understanding the causes of intravenous medication administration errors in hospitals: a qualitative critical incident study

    PubMed Central

    Keers, Richard N; Williams, Steven D; Cooke, Jonathan; Ashcroft, Darren M

    2015-01-01

    Objectives To investigate the underlying causes of intravenous medication administration errors (MAEs) in National Health Service (NHS) hospitals. Setting Two NHS teaching hospitals in the North West of England. Participants Twenty nurses working in a range of inpatient clinical environments were identified and recruited using purposive sampling at each study site. Primary outcome measures Semistructured interviews were conducted with nurse participants using the critical incident technique, where they were asked to discuss perceived causes of intravenous MAEs that they had been directly involved with. Transcribed interviews were analysed using the Framework approach and emerging themes were categorised according to Reason's model of accident causation. Results In total, 21 intravenous MAEs were discussed containing 23 individual active failures which included slips and lapses (n=11), mistakes (n=8) and deliberate violations of policy (n=4). Each active failure was associated with a range of error and violation provoking conditions. The working environment was implicated when nurses lacked healthcare team support and/or were exposed to a perceived increased workload during ward rounds, shift changes or emergencies. Nurses frequently reported that the quality of intravenous dose-checking activities was compromised due to high perceived workload and working relationships. Nurses described using approaches such as subconscious functioning and prioritising to manage their duties, which at times contributed to errors. Conclusions Complex interactions between active and latent failures can lead to intravenous MAEs in hospitals. Future interventions may need to be multimodal in design in order to mitigate these risks and reduce the burden of intravenous MAEs. PMID:25770226

  18. Electronic Absolute Cartesian Autocollimator

    NASA Technical Reports Server (NTRS)

    Leviton, Douglas B.

    2006-01-01

    An electronic absolute Cartesian autocollimator performs the same basic optical function as does a conventional all-optical or a conventional electronic autocollimator but differs in the nature of its optical target and the manner in which the position of the image of the target is measured. The term absolute in the name of this apparatus reflects the nature of the position measurement, which, unlike in a conventional electronic autocollimator, is based absolutely on the position of the image rather than on an assumed proportionality between the position and the levels of processed analog electronic signals. The term Cartesian in the name of this apparatus reflects the nature of its optical target. Figure 1 depicts the electronic functional blocks of an electronic absolute Cartesian autocollimator along with its basic optical layout, which is the same as that of a conventional autocollimator. Referring first to the optical layout and functions only, this or any autocollimator is used to measure the compound angular deviation of a flat datum mirror with respect to the optical axis of the autocollimator itself. The optical components include an illuminated target, a beam splitter, an objective or collimating lens, and a viewer or detector (described in more detail below) at a viewing plane. The target and the viewing planes are focal planes of the lens. Target light reflected by the datum mirror is imaged on the viewing plane at unit magnification by the collimating lens. If the normal to the datum mirror is parallel to the optical axis of the autocollimator, then the target image is centered on the viewing plane. Any angular deviation of the normal from the optical axis manifests itself as a lateral displacement of the target image from the center. The magnitude of the displacement is proportional to the focal length and to the magnitude (assumed to be small) of the angular deviation. The direction of the displacement is perpendicular to the axis about which the

  19. 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.

  20. Refractive Errors

    MedlinePlus

    ... and lens of your eye helps you focus. Refractive errors are vision problems that happen when the ... cornea, or aging of the lens. Four common refractive errors are Myopia, or nearsightedness - clear vision close ...

  1. Implants as absolute anchorage.

    PubMed

    Rungcharassaeng, Kitichai; Kan, Joseph Y K; Caruso, Joseph M

    2005-11-01

    Anchorage control is essential for successful orthodontic treatment. Each tooth has its own anchorage potential as well as propensity to move when force is applied. When teeth are used as anchorage, the untoward movements of the anchoring units may result in the prolonged treatment time, and unpredictable or less-than-ideal outcome. To maximize tooth-related anchorage, techniques such as differential torque, placing roots into the cortex of the bone, the use of various intraoral devices and/or extraoral appliances have been implemented. Implants, as they are in direct contact with bone, do not possess a periodontal ligament. As a result, they do not move when orthodontic/orthopedic force is applied, and therefore can be used as "absolute anchorage." This article describes different types of implants that have been used as orthodontic anchorage. Their clinical applications and limitations are also discussed. PMID:16463910

  2. Absolute Equilibrium Entropy

    NASA Technical Reports Server (NTRS)

    Shebalin, John V.

    1997-01-01

    The entropy associated with absolute 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.

  3. It's not just the alcohol: gender, alcohol use, and intimate partner violence in Mae La refugee camp, Thailand, 2009.

    PubMed

    Ezard, Nadine

    2014-05-01

    Alcohol use is common in many conflict-displaced populations; population perspectives of alcohol use have not been well studied. Interviews were conducted with a convenience sample of 97 people (September-December 2009) in Mae La, a long-standing refugee camp on the Thai-Burma border, and analyzed thematically. Intimate partner violence (IPV) emerged as a prominent theme, with four subthemes: alcohol use is subject to strongly gendered social controls; alcohol use is changing under the pressures of displacement; IPV is an emergent alcohol-related harm; the relationship between IPV and alcohol is complex. The study's limitations are noted, and future practice and research directions are discussed. PMID:24377756

  4. Spatially resolved absolute spectrophotometry of Saturn - 3390 to 8080 A

    NASA Technical Reports Server (NTRS)

    Bergstralh, J. T.; Diner, D. J.; Baines, K. H.; Neff, J. S.; Allen, M. A.; Orton, G. S.

    1981-01-01

    A series of spatially resolved absolute spectrophotometric measurements of Saturn was conducted for the expressed purpose of calibrating the data obtained with the Imaging Photopolarimeter (IPP) on Pioneer 11 during its recent encounter with Saturn. All observations reported were made at the Mt. Wilson 1.5-m telescope, using a 1-m Ebert-Fastie scanning spectrometer. Spatial resolution was 1.92 arcsec. Photometric errors are considered, taking into account the fixed error, the variable error, and the composite error. The results are compared with earlier observations, as well as with synthetic spectra derived from preliminary physical models, giving attention to the equatorial region and the South Temperate Zone.

  5. Absolute neutrino mass measurements

    NASA Astrophysics Data System (ADS)

    Wolf, Joachim

    2011-10-01

    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 (0v2β) searches, single β-decay experiments provide a direct, model-independent way to determine the absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy. 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 β-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 (137Rh) 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&D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2β decay and single β-decay.

  6. Absolute neutrino mass measurements

    SciTech Connect

    Wolf, Joachim

    2011-10-06

    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 absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy.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.

  7. An absolute radius scale for Saturn's rings

    NASA Technical Reports Server (NTRS)

    Nicholson, Philip D.; Cooke, Maren L.; Pelton, Emily

    1990-01-01

    Radio and stellar occultation observations of Saturn's rings made by the Voyager spacecraft are discussed. The data reveal systematic discrepancies of almost 10 km in some parts of the rings, limiting some of the investigations. A revised solution for Saturn's rotation pole has been proposed which removes the discrepancies between the stellar and radio occultation profiles. Corrections to previously published radii vary from -2 to -10 km for the radio occultation, and +5 to -6 km for the stellar occultation. An examination of spiral density waves in the outer A Ring supports that the revised absolute radii are in error by no more than 2 km.

  8. Absolute method of measuring magnetic susceptibility

    USGS Publications Warehouse

    Thorpe, A.; Senftle, F.E.

    1959-01-01

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

  9. Development and application of microwave assisted extraction (MAE) for the extraction of five polycyclic aromatic hydrocarbons in sediment samples in Johannesburg area, South Africa.

    PubMed

    Sibiya, Precious; Chimuka, Luke; Cukrowska, Ewa; Tutu, Hlanganani

    2013-07-01

    A microwave-assisted extraction (MAE) method was verified and applied for the extraction of polycyclic aromatic hydrocarbons (PAHs) in sediment samples. Soxhlet extraction was used as the reference method. The optimum MAE was carried out with 20 mL of hexane/acetone (1:1, v/v) mixture in a 1-g sample at 250 W for 20 min. Soxhlet extraction was carried out with 250 mL of dichloromethane:hexane (1:1, v/v) mixture in a 15-g sample for 24 h in a water bath maintained at 60 °C. The collected extracts were both cleaned up, reduced to 1 mL under nitrogen and then injected into an HPLC fluorescence. To increase the sample throughput, simultaneous MAE was performed. The obtained percentage recoveries ranged from 61 to 93 and 88-98 for MAE and SE, respectively. The optimised MAE method was validated using certified reference material. It was then applied to real sediment samples from in and around the greater Johannesburg area. The sediments from Jukskei River were found to be the most polluted while Hartbeespoort Dam sediments were found to be least polluted. The overall order of concentrations for the studied PAHs per site was as follows: Jukskei River > Kempton Park > Centurion Dams > Natalspruit River (PIT) > Hartbeespoort Dam. PMID:23108712

  10. Additional Burden of Diseases Associated with Cadmium Exposure: A Case Study of Cadmium Contaminated Rice Fields in Mae Sot District, Tak Province, Thailand

    PubMed Central

    Songprasert, Nisarat; Sukaew, Thitiporn; Kusreesakul, Khanitta; Swaddiwudhipong, Witaya; Padungtod, Chantana; Bundhamcharoen, Kanitta

    2015-01-01

    The cadmium (Cd) contaminated rice fields in Mae Sot District, Tak Province, Thailand has been one of the major environmental problems in Thailand for the last 10 years. We used disability adjusted life years (DALYs) to estimate the burden of disease attributable to Cd in terms of additional DALYs of Mae Sot residents. Cd exposure data included Cd and β2–microglobulin (β2-MG) in urine (as an internal exposure dose) and estimated cadmium daily intake (as an external exposure dose). Compared to the general Thai population, Mae Sot residents gained 10%–86% DALYs from nephrosis/nephritis, heart diseases, osteoporosis and cancer depending on their Cd exposure type and exposure level. The results for urinary Cd and dietary Cd intake varied according to the studies used for risk estimation. The ceiling effect was observed in results using dietary Cd intake because of the high Cd content in rice grown in the Mae Sot area. The results from β2-MG were more robust with additional DALYs ranging from 36%–86% for heart failure, cerebral infarction, and nephrosis/nephritis. Additional DALYs is a useful approach for assessing the magnitude of environmental Cd exposure. The Mae Sot population lost more healthy life compared to populations living in a non- or less Cd polluted area. This method should be applicable to various types of environmental contamination problems if exposure assessment information is available. PMID:26262629

  11. The development and implementation of a mesoscale modeling system for simulating the meteorology and air quality situation in the Mae Moh Valley

    NASA Astrophysics Data System (ADS)

    Kowalewsky, Karen Jean

    2001-08-01

    The Mae Moh Valley region of northern Thailand experiences frequent pollutant fumigation events during the annual cool season. The onset and magnitude of these events are driven by the synoptic scale and mesoscale conditions that develop over the Valley during the cool season. A conclusion from previous studies conducted in the Valley was that to properly predict the onset and magnitude of the fumigation events, a three dimensional wind field generated using a mesoscale meteorological model needed to be used in a mesoscale transport and dispersion model. The results of the previous studies led to the modeling analysis presented in this dissertation. The research hypothesis was that it would be possible to develop a mesoscale dispersion modeling system that could simulate the Valley fumigation events. The null hypothesis was that the air dispersion modeling system could not simulate the fumigation events. The Penn State/NCAR Mesoscale Meteorological Model, Version 5 (MM5) was used to generate the mesoscale meteorological parameters used as input to the United States Environmental Protection Agency (USEPA) CALMET/CALPUFF mesoscale dispersion and transport model. These models were used to forecast one fumigation event observed in 1997. Three model scenarios were considered for the fumigation event. The differences in the model scenarios were a function of modifications to terrain and horizontal and vertical grid resolutions used by MM5. Output from the combined MM5/CALMET/CALPUFF was compared with observations to document the modeling system's strengths and limitations. The results from this study indicated that MM5 appeared to be capable of simulating the temperature profile required to produce a fumigation event in the Valley. However, due to errors in the input meteorological data, MM5 was not capable of forecasting the light and variable wind conditions present within the Valley prior to and during the fumigation events. These wind field errors contributed to

  12. Changes in depositional environments from Ordovician to tertiary of carbonate rocks in Tak-Mae Sod area, Northwest Thailand

    NASA Astrophysics Data System (ADS)

    Ratanasthien, Benjavun

    Carbonate rocks ranging in age from Ordovician to Tertiary along the Tak-Mae Sod and Mae Sod-Umphang highways were analysed mineralogically, petrographically, and geochemically. The study revealed the depositional environment of the mainly chemical precipitated Ordovician carbonate rocks to be in shallow (lagoonal?) waters of a warm climate. The Carboniferous carbonates were chemically deposited in moderately deep to deep water as indicated by siliceous limestone composed mainly of calcite and radiolarian chert and/or interbedded chert bands. The environment changed to shallower water during the Permo-Carboniferous as seen in the Pra Woh Limestone. The carbonates are characterized by pale colour dolomite, dolomitic limestone and calcareous sandstone. They are sometimes, fossiliferous, mainly bryozoa, foraminifera, corals, gastropods and bivalves. During Triassic to Jurassic, the carbonates were deposited in comparatively shallow and/or closed basins as indicated by alternating sequences of dark to black limestone, calcareous shale and calcareous sandstone. The rocks are composed of high carbonaceous material and clays with few fossils associated. The environment changed to brackish and eventually to fresh water during the Tertiary indicated by fossiliferous limestone (pelycypods and gastropods) and dolomitic limestone which are chemically precipitated in fresh water.

  13. Absolute Identification by Relative Judgment

    ERIC Educational Resources Information Center

    Stewart, Neil; Brown, Gordon D. A.; Chater, Nick

    2005-01-01

    In unidimensional absolute 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 absolute magnitudes. The authors propose an alternative…

  14. Be Resolute about Absolute Value

    ERIC Educational Resources Information Center

    Kidd, Margaret L.

    2007-01-01

    This article explores how conceptualization of absolute value can start long before it is introduced. The manner in which absolute 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…

  15. Absolute surface metrology by rotational averaging in oblique incidence interferometry.

    PubMed

    Lin, Weihao; He, Yumei; Song, Li; Luo, Hongxin; Wang, Jie

    2014-06-01

    A modified method for measuring the absolute figure of a large optical flat surface in synchrotron radiation by a small aperture interferometer is presented. The method consists of two procedures: the first step is oblique incidence measurement; the second is multiple rotating measurements. This simple method is described in terms of functions that are symmetric or antisymmetric with respect to reflections at the vertical axis. Absolute deviations of a large flat surface could be obtained when mirror antisymmetric errors are removed by N-position rotational averaging. Formulas are derived for measuring the absolute surface errors of a rectangle flat, and experiments on high-accuracy rectangle flats are performed to verify the method. Finally, uncertainty analysis is carried out in detail. PMID:24922410

  16. Medication Errors

    MedlinePlus

    ... to reduce the risk of medication errors to industry and others at FDA. Additionally, DMEPA prospectively reviews ... List of Abbreviations Regulations and Guidances Guidance for Industry: Safety Considerations for Product Design to Minimize Medication ...

  17. Medication Errors

    MedlinePlus

    Medicines cure infectious diseases, prevent problems from chronic diseases, and ease pain. But medicines can also cause harmful reactions if not used ... You can help prevent errors by Knowing your medicines. Keep a list of the names of your ...

  18. Analysis of dextromethorphan and dextrorphan in decomposed skeletal tissues by microwave assisted extraction, microplate solid-phase extraction and gas chromatography- mass spectrometry (MAE-MPSPE-GCMS).

    PubMed

    Fraser, Candice D; Cornthwaite, Heather M; Watterson, James H

    2015-08-01

    Analysis of decomposed skeletal tissues for dextromethorphan (DXM) and dextrorphan (DXT) using microwave assisted extraction (MAE), microplate solid-phase extraction (MPSPE) and gas chromatography-mass spectrometry (GC-MS) is described. Rats (n = 3) received 100 mg/kg DXM (i.p.) and were euthanized by CO2 asphyxiation roughly 20 min post-dose. Remains decomposed to skeleton outdoors and vertebral bones were recovered, cleaned, and pulverized. Pulverized bone underwent MAE using methanol as an extraction solvent in a closed microwave system, followed by MPSPE and GC-MS. Analyte stability under MAE conditions was assessed and found to be stable for at least 60 min irradiation time. The majority (>90%) of each analyte was recovered after 15 min. The MPSPE-GCMS method was fit to a quadratic response (R(2)  > 0.99), over the concentration range 10-10 000 ng⋅mL(-1) , with coefficients of variation <20% in triplicate analysis. The MPSPE-GCMS method displayed a limit of detection of 10 ng⋅mL(-1) for both analytes. Following MAE for 60 min (80 °C, 1200 W), MPSPE-GCMS analysis of vertebral bone of DXM-exposed rats detected both analytes in all samples (DXM: 0.9-1.5 µg⋅g(-1) ; DXT: 0.5-1.8 µg⋅g(-1) ). PMID:25487525

  19. Absolute Radiometer for Reproducing the Solar Irradiance Unit

    NASA Astrophysics Data System (ADS)

    Sapritskii, V. I.; Pavlovich, M. N.

    1989-01-01

    A high-precision absolute radiometer with a thermally stabilized cavity as receiving element has been designed for use in solar irradiance measurements. The State Special Standard of the Solar Irradiance Unit has been built on the basis of the developed absolute radiometer. The Standard also includes the sun tracking system and the system for automatic thermal stabilization and information processing, comprising a built-in microcalculator which calculates the irradiance according to the input program. During metrological certification of the Standard, main error sources have been analysed and the non-excluded systematic and accidental errors of the irradiance-unit realization have been determined. The total error of the Standard does not exceed 0.3%. Beginning in 1984 the Standard has been taking part in a comparison with the Å 212 pyrheliometer and other Soviet and foreign standards. In 1986 it took part in the international comparison of absolute radiometers and standard pyrheliometers of socialist countries. The results of the comparisons proved the high metrological quality of this Standard based on an absolute radiometer.

  20. In Vitro Antibacterial Activity of a Novel Resin-Based Pulp Capping Material Containing the Quaternary Ammonium Salt MAE-DB and Portland Cement

    PubMed Central

    Zhang, Hongchen; Zhou, Wei; Ban, Jinghao; Wei, Jingjing; Liu, Yan; Gao, Jing; Chen, Jihua

    2014-01-01

    Background Vital pulp preservation in the treatment of deep caries is challenging due to bacterial infection. The objectives of this study were to synthesize a novel, light-cured composite material containing bioactive calcium-silicate (Portland cement, PC) and the antimicrobial quaternary ammonium salt monomer 2-methacryloxylethyl dodecyl methyl ammonium bromide (MAE-DB) and to evaluate its effects on Streptococcus mutans growth in vitro. Methods The experimental material was prepared from a 2∶1 ratio of PC mixed with a resin of 2-hydroxyethylmethacrylate, bisphenol glycerolate dimethacrylate, and triethylene glycol dimethacrylate (4∶3∶1) containing 5 wt% MAE-DB. Cured resin containing 5% MAE-DB without PC served as the positive control material, and resin without MAE-DB or PC served as the negative control material. Mineral trioxide aggregate (MTA) and calcium hydroxide (Dycal) served as commercial controls. S. mutans biofilm formation on material surfaces and growth in the culture medium were tested according to colony-forming units (CFUs) and metabolic activity after 24 h incubation over freshly prepared samples or samples aged in water for 6 months. Biofilm formation was also assessed by Live/Dead staining and scanning electron microscopy. Results S. mutans biofilm formation on the experimental material was significantly inhibited, with CFU counts, metabolic activity, viability staining, and morphology similar to those of biofilms on the positive control material. None of the materials affected bacterial growth in solution. Contact-inhibition of biofilm formation was retained by the aged experimental material. Significant biofilm formation was observed on MTA and Dycal. Conclusion The synthesized material containing HEMA-BisGMA-TEGDMA resin with MAE-DB as the antimicrobial agent and PC to support mineralized tissue formation inhibited S. mutans biofilm formation even after aging in water for 6 months, but had no inhibitory effect on bacteria in solution

  1. 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.

  2. Absolute geostrophic currents in global tropical oceans

    NASA Astrophysics Data System (ADS)

    Yang, Lina; Yuan, Dongliang

    2016-03-01

    A set of absolute 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 time 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.

  3. Stitching interferometry: recent results and absolute calibration

    NASA Astrophysics Data System (ADS)

    Bray, Michael

    2004-02-01

    Stitching Interferometry is a method of analysing large optical components using a standard "small" interferometer. This result is obtained by taking multiple overlapping images of the large component, and numerically "stitching" these sub-apertures together. We have already reported the industrial use our Stitching Interferometry systems (Previous SPIE symposia), but experimental results had been lacking because this technique is still new, and users needed to get accustomed to it before producing reliable measurements. We now have more results. We will report user comments and show new, unpublished results. We will discuss sources of error, and show how some of these can be reduced to arbitrarily small values. These will be discussed in some detail. We conclude with a few graphical examples of absolute measurements performed by us.

  4. Laboratory Study of Quaternary Sediment Resistivity Related to Groundwater Contamination at Mae-Hia Landfill, Mueang District, Chiang Mai Province

    NASA Astrophysics Data System (ADS)

    Sichan, N.

    2007-12-01

    This study was aimed to understand the nature of the resistivity value of the sediment when it is contaminated, in order to use the information solving the obscure interpretation in the field. The pilot laboratory experiments were designed to simulate various degree of contamination and degree of saturation then observe the resulting changes in resistivity. The study was expected to get a better understanding of how various physical parameters effect the resistivity values in term of mathematic function. And also expected to apply those obtained function to a practical quantitatively interpretation. The sediment underlying the Mae-Hia Landfill consists of clay-rich material, with interfingerings of colluvium and sandy alluvium. A systematic study identified four kinds of sediment, sand, clayey sand, sandy clay, and clay. Representative sediment and leachate samples were taken from the field and returned to the laboratory. Both the physical and chemical properties of the sediments and leachate were analyzed to delineate the necessary parameters that could be used in Archie's equation. Sediment samples were mixed with various concentration of leachate solutions. Then the resistivity values were measured at various controlled steps in the saturation degree in a well- calibrated six-electrode model resistivity box. The measured resistivity values for sand, clayey sand, sandy clay when fully and partly saturated were collected, then plotted and fitted to Archie's equation, to obtain a mathematical relationship between bulk resistivity, porosity, saturation degree and resistivity of pore fluid. The results fit well to Archie's equation, and it was possible to determine all the unknown parameters representative of the sediment samples. For sand, clayey sand, sandy clay, and clay, the formation resistivity factors (F) are 2.90, 5.77, 7.85, and 7.85 with the products of cementation factor (m) and the pore geometry factors (a) (in term of -am) are 1.49, -1.63, -1.92, -2

  5. 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.-

  6. Absolute measurement of the extreme UV solar flux

    NASA Technical Reports Server (NTRS)

    Carlson, R. W.; Ogawa, H. S.; Judge, D. L.; Phillips, E.

    1984-01-01

    A windowless rare-gas ionization chamber has been developed to measure the absolute value of the solar extreme UV flux in the 50-575-A region. Successful results were obtained on a solar-pointing sounding rocket. The ionization chamber, operated in total absorption, is an inherently stable absolute detector of ionizing UV radiation and was designed to be independent of effects from secondary ionization and gas effusion. The net error of the measurement is + or - 7.3 percent, which is primarily due to residual outgassing in the instrument, other errors such as multiple ionization, photoelectron collection, and extrapolation to the zero atmospheric optical depth being small in comparison. For the day of the flight, Aug. 10, 1982, the solar irradiance (50-575 A), normalized to unit solar distance, was found to be 5.71 + or - 0.42 x 10 to the 10th photons per sq cm sec.

  7. Contamination of nitrate in groundwater and its potential human health: a case study of lower Mae Klong river basin, Thailand.

    PubMed

    Wongsanit, Jaturong; Teartisup, Piyakarn; Kerdsueb, Prapeut; Tharnpoophasiam, Prapin; Worakhunpiset, Suwalee

    2015-08-01

    Nitrate contamination in groundwater is a worldwide problem especially in agricultural countries. Environmental factors, such as land-use pattern, type of aquifer, and soil-drainage capacity, affect the level of contamination. Exposure to high levels of nitrate in groundwater may contribute to adverse health effects among residents who use groundwater for consumption. This study aimed to determine the relationship between nitrate levels in groundwater with land-use pattern, type of aquifer, and soil-drainage capacity, in Photharam District, Ratchaburi Province, lower Mae Klong basin, Thailand. Health risk maps were created based on hazard quotient to quantify the potential health risk of the residents using US Environmental Protection Agency (U.S. EPA) health risk assessment model. The results showed the influence of land-use patterns, type of aquifer, and soil-drainage capacity on nitrate contamination. It was found that most of the residents in the studied area were not at risk; however, a groundwater nitrate monitoring system should be implemented. PMID:25874425

  8. High prevalence of bancroftian filariasis in Myanmar-migrant workers: a study in Mae Sot district, Tak province, Thailand.

    PubMed

    Triteeraprapab, S; Songtrus, J

    1999-07-01

    Although the prevalence of lymphatic filariasis in the Thai population is low, migration of Myanmar labor into Thailand may increase the incidence of bancroftian filariasis. Epidemiology of filariasis in Myanmars has not been precisely determined. By using microscopic examination, we found that the microfilarial rate in 654 Myanmar migrants working in Mae Sot, Tak province, was 4.4 per cent. The highest microfilarial rate was found in males aged 21-30 years (6.8%). History of mosquito bites was significantly correlated with microfilaremia. The majority of Myanmar migrants (55.5%) have been staying in Thailand 1-6 years; most (82.0%) have never been back to Myanmar. Seventy-nine per cent of infected Myanmars were from Moulmein (Maulamyine) city. Since these migrants carry the parasite with high infected rate and the mosquito vector Culex quinquefasciatus is also prevalent in Thailand, Thai people are at high risk of acquiring this disease if good control and prevention strategies are not implemented. PMID:10511777

  9. Mathematical Model for Absolute Magnetic Measuring Systems in Industrial Applications

    NASA Astrophysics Data System (ADS)

    Fügenschuh, Armin; Fügenschuh, Marzena; Ludszuweit, Marina; Mojsic, Aleksandar; Sokół, Joanna

    2015-09-01

    Scales for measuring systems are either based on incremental or absolute 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. Absolute 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 absolute 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 absolute positions from the set of unique measured values. We compare two patterns with respect to uniqueness, accuracy, 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.

  10. Absolute optical surface measurement with deflectometry

    NASA Astrophysics Data System (ADS)

    Li, Wansong; Sandner, Marc; Gesierich, Achim; Burke, Jan

    Deflectometry utilises the deformation and displacement of a sample pattern after reflection from a test surface to infer the surface slopes. Differentiation of the measurement data leads to a curvature map, which is very useful for surface quality checks with sensitivity down to the nanometre range. Integration of the data allows reconstruction of the absolute surface shape, but the procedure is very error-prone because systematic errors may add up to large shape deviations. In addition, there are infinitely many combinations for slope and object distance that satisfy a given observation. One solution for this ambiguity is to include information on the object's distance. It must be known very accurately. Two laser pointers can be used for positioning the object, and we also show how a confocal chromatic distance sensor can be used to define a reference point on a smooth surface from which the integration can be started. The used integration algorithm works without symmetry constraints and is therefore suitable for free-form surfaces as well. Unlike null testing, deflectometry also determines radius of curvature (ROC) or focal lengths as a direct result of the 3D surface reconstruction. This is shown by the example of a 200 mm diameter telescope mirror, whose ROC measurements by coordinate measurement machine and deflectometry coincide to within 0.27 mm (or a sag error of 1.3μm). By the example of a diamond-turned off-axis parabolic mirror, we demonstrate that the figure measurement uncertainty comes close to a well-calibrated Fizeau interferometer.

  11. Optomechanics for absolute rotation detection

    NASA Astrophysics Data System (ADS)

    Davuluri, Sankar

    2016-07-01

    In this article, we present an application of optomechanical cavity for the absolute 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 absolute 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.

  12. The Absolute Spectrum Polarimeter (ASP)

    NASA Technical Reports Server (NTRS)

    Kogut, A. J.

    2010-01-01

    The Absolute Spectrum Polarimeter (ASP) is an Explorer-class mission to map the absolute 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.

  13. Effect of automated drug distribution systems on medication error rates in a short-stay geriatric unit

    PubMed Central

    Cousein, Etienne; Mareville, Julie; Lerooy, Alexandre; Caillau, Antoine; Labreuche, Julien; Dambre, Delphine; Odou, Pascal; Bonte, Jean-Paul; Puisieux, François; Decaudin, Bertrand; Coupé, Patrick

    2014-01-01

    Rationale, aims and objectives To assess the impact of an automated drug distribution system on medication errors (MEs). Methods Before-after observational study in a 40-bed short stay geriatric unit within a 1800 bed general hospital in Valenciennes, France. Researchers attended nurse medication administration rounds and compared administered to prescribed drugs, before and after the drug distribution system changed from a ward stock system (WSS) to a unit dose dispensing system (UDDS), integrating a unit dose dispensing robot and automated medication dispensing cabinet (AMDC). Results A total of 615 opportunities of errors (OEs) were observed among 148 patients treated during the WSS period, and 783 OEs were observed among 166 patients treated during the UDDS period. ME [medication administration error (MAE)] rates were calculated and compared between the two periods. Secondary measures included type of errors, seriousness of errors and risk reduction for the patients. The implementation of an automated drug dispensing system resulted in a 53% reduction in MAEs. All error types were reduced in the UDDS period compared with the WSS period (P < 0.001). Wrong dose and wrong drug errors were reduced by 79.1% (2.4% versus 0.5%, P = 0.005) and 93.7% (1.9% versus 0.01%, P = 0.009), respectively. Conclusion An automated UDDS combining a unit dose dispensing robot and AMDCs could reduce discrepancies between ordered and administered drugs, thus improving medication safety among the elderly. PMID:24917185

  14. A field-scale study of cadmium phytoremediation in a contaminated agricultural soil at Mae Sot District, Tak Province, Thailand: (1) Determination of Cd-hyperaccumulating plants.

    PubMed

    Khaokaew, Saengdao; Landrot, Gautier

    2015-11-01

    The cadmium (Cd) phytoremediation capabilities of Gynura pseudochina, Chromolaena odorata, Conyza sumatrensis, Crassocephalum crepidioides and Nicotiana tabacum were determined by conducting in-situ experiments in a highly Cd-contaminated agricultural field at Mae Sot District, Tak Province, Thailand. Most of these five plant species, which are commonly found in Thailand, previously demonstrated Cd-hyperaccumulating capacities under greenhouse conditions. This study represented an important initial step in determining if any of these plants could, under field-conditions, effectively remove Cd from the Mae Sot contaminated fields, which represent a health threat to thousands of local villagers. All plant species had at least a 95% survival rate on the final harvest day. Additionally, all plant species, except C. odorata, could hyperaccumulate the extractable Cd amounts present in the soil, based on their associated Bioaccumulation Factor (BAF), Translocation Factor (TF), and background Vegetation Factor (VF). Therefore, the four Cd-hyperaccumulating plant species identified in this study may successfully treat a majority of contaminated fields at Mae Sot, as it was previously reported that Cd amounts present in a number of these soils were mostly available. PMID:25454203

  15. Comparison of Different Extraction Methods for Analysis of 10 Organochlorine Pesticides: Application of MAE-SPE Method in Soil from Beijing.

    PubMed

    Di, Shanshan; Shi, Shengchao; Xu, Peng; Diao, Jinling; Zhou, Zhiqiang

    2015-07-01

    Four commonly applied extraction techniques for organochlorine pesticides, microwave-assisted extraction (MAE), accelerated solvent extraction (ASE), quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and ultrasonic solvent extraction, were applied on soil samples in order to evaluate their performances. The extracts were analyzed by GC-ECD and confirmed by GC-MS/MS. The MAE and QuEChERS extraction methods generally yielded higher results compared to the ultrasonication and ASE methods, while the lowest recovery (56.8 %) for o,p'-DDD was obtained using the QuEChERS method. The MAE method was further applied to six different soils from Beijing. In the soil samples only α-endosulfan and β-endosulfan were not detected. The ratios of α-HCH/γ-HCH and α-HCH/β-HCH indicated HCH residues likely originated from historical use of HCHs, and that technical HCHs were not likely being currently applied in Beijing. PMID:25935331

  16. The AFGL absolute gravity program

    NASA Technical Reports Server (NTRS)

    Hammond, J. A.; Iliff, R. L.

    1978-01-01

    A brief discussion of the AFGL's (Air Force Geophysics Laboratory) program in absolute 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 accuracy 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.

  17. Absolute calibration of forces in optical tweezers

    NASA Astrophysics Data System (ADS)

    Dutra, R. S.; Viana, N. B.; Maia Neto, P. A.; Nussenzveig, H. M.

    2014-07-01

    Optical tweezers are highly versatile laser traps for neutral microparticles, with fundamental applications in physics and in single molecule cell biology. Force measurements are performed by converting the stiffness response to displacement of trapped transparent microspheres, employed as force transducers. Usually, calibration is indirect, by comparison with fluid drag forces. This can lead to discrepancies by sizable factors. Progress achieved in a program aiming at absolute calibration, conducted over the past 15 years, is briefly reviewed. Here we overcome its last major obstacle, a theoretical overestimation of the peak stiffness, within the most employed range for applications, and we perform experimental validation. The discrepancy is traced to the effect of primary aberrations of the optical system, which are now included in the theory. All required experimental parameters are readily accessible. Astigmatism, the dominant effect, is measured by analyzing reflected images of the focused laser spot, adapting frequently employed video microscopy techniques. Combined with interface spherical aberration, it reveals a previously unknown window of instability for trapping. Comparison with experimental data leads to an overall agreement within error bars, with no fitting, for a broad range of microsphere radii, from the Rayleigh regime to the ray optics one, for different polarizations and trapping heights, including all commonly employed parameter domains. Besides signaling full first-principles theoretical understanding of optical tweezers operation, the results may lead to improved instrument design and control over experiments, as well as to an extended domain of applicability, allowing reliable force measurements, in principle, from femtonewtons to nanonewtons.

  18. Absolute Timing Calibration of the USA Experiment Using Pulsar Observations

    NASA Astrophysics Data System (ADS)

    Ray, P. S.; Wood, K. S.; Wolff, M. T.; Lovellette, M. N.; Sheikh, S.; Moon, D.-S.; Eikenberry, S. S.; Roberts, M.; Lyne, A.; Jordon, C.; Bloom, E. D.; Tournear, D.; Saz Parkinson, P.; Reilly, K.

    2003-03-01

    We update the status of the absolute time calibration of the USA Experiment as determined by observations of X-ray emitting rotation-powered pulsars. The brightest such source is the Crab Pulsar and we have obtained observations of the Crab at radio, IR, optical, and X-ray wavelengths. We directly compare arrival time determinations for 2--10 keV X-ray observations made contemporaneously with the PCA on the Rossi X-ray Timing Explorer and the USA Experiment on ARGOS. These two X-ray measurements employ very different means of measuring time and satellite position and thus have different systematic error budgets. The comparison with other wavelengths requires additional steps such as dispersion measure corrections and a precise definition of the ``peak'' of the light curve since the light curve shape varies with observing wavelength. We will describe each of these effects and quantify the magnitude of the systematic error that each may contribute. We will also include time comparison results for other pulsars, such as PSR B1509-58 and PSR B1821-24. Once the absolute time calibrations are well understood, comparing absolute arrival times at multiple energies can provide clues to the magnetospheric structure and emission region geometry. Basic research on X-ray Astronomy at NRL is funded by NRL/ONR.

  19. [Diagnostic Errors in Medicine].

    PubMed

    Buser, Claudia; Bankova, Andriyana

    2015-12-01

    The recognition of diagnostic errors in everyday practice can help improve patient safety. The most common diagnostic errors are the cognitive errors, followed by system-related errors and no fault errors. The cognitive errors often result from mental shortcuts, known as heuristics. The rate of cognitive errors can be reduced by a better understanding of heuristics and the use of checklists. The autopsy as a retrospective quality assessment of clinical diagnosis has a crucial role in learning from diagnostic errors. Diagnostic errors occur more often in primary care in comparison to hospital settings. On the other hand, the inpatient errors are more severe than the outpatient errors. PMID:26649954

  20. Cosmology with negative absolute temperatures

    NASA Astrophysics Data System (ADS)

    Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony

    2016-08-01

    Negative absolute 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.

  1. Risky alcohol use among reproductive-age men, not women, in Mae La refugee camp, Thailand, 2009

    PubMed Central

    2012-01-01

    Background Globally, alcohol use contributes to close to 4% of all deaths and is a leading cause of ill health and premature death among men of reproductive age. Problem alcohol use is an unaddressed public health issue among populations displaced by conflict. Assessing the magnitude of the problem and identifying affected groups and risk behaviours is difficult in mobile and unstable populations. Methods From 15–28 December 2009 we conducted a simple rapid screening test of risky alcohol use using the single item modified Short Assessment Screening Questionnaire (mSASQ) by all women currently enrolled in the antenatal care clinic in Mae La refugee camp, a long standing displaced setting on the Thai Burma border. Women self- reported and gave a secondary report of their male partners. Gender differences in alcohol use were further explored in semi-structured interviews with camp residents on attitudes, behaviours, and beliefs regarding alcohol and analysed thematically. Results Of 636 women screened in the antenatal clinic, almost none (0.2%, 95CI 0.0-0.9%) reported risky alcohol use prior to pregnancy, whereas around a quarter (24.4%, 95CI 21.2-27.9%) reported risky alcohol use by their male partners. Interviews with 97 camp residents described strong social controls against women’s alcohol use and men’s drinking to intoxication, despite a dominant perception that the social context of life in displacement promoted alcohol use and that controls are loosening. Conclusions As a stigmatised behaviour, alcohol use is difficult to assess, particularly in the context of highly mobile adult male populations: the simple assessment methods here show that it is feasible to obtain adequate data for the purposes of intervention design. The data suggest that risky drinking is common and normalised among men, but that the population may have been partially protected from rapid rises in problem alcohol use observed in nation-wide data from Thailand. The changing social

  2. The absolute radiometric calibration of the advanced very high resolution radiometer

    NASA Technical Reports Server (NTRS)

    Slater, P. N.; Teillet, P. M.; Ding, Y.

    1988-01-01

    The need for independent, redundant absolute radiometric calibration methods is discussed with reference to the Thematic Mapper. Uncertainty requirements for absolute calibration of between 0.5 and 4 percent are defined based on the accuracy of reflectance retrievals at an agricultural site. It is shown that even very approximate atmospheric corrections can reduce the error in reflectance retrieval to 0.02 over the reflectance range 0 to 0.4.

  3. Monitoring of arsenic in aquatic plants, water, and sediment of wastewater treatment ponds at the Mae Moh Lignite power plant, Thailand.

    PubMed

    Nateewattana, Jomjun; Trichaiyaporn, Siripen; Saouy, Maliwan; Nateewattana, Jintapat; Thavornyutikarn, Prasak; Pengchai, Petch; Choonluchanon, Somporn

    2010-06-01

    Mae Moh is a risky area for arsenic contamination caused by the effluent from biowetland ponds in Mae Moh lignite-fuelled power plant. The objective of this study was to investigate the arsenic concentrations of Mae Moh biowetland ponds and determine the main factors which are important for arsenic phytoremediation in the treatment system. The result revealed that arsenic concentrations in the supernant were in the range of less than 1.0 microg As L(-1) to 2.0 microg As L(-1) while those in the sediment were in the range of 25-200 microg As kg soil(-1). Both values were below the Thailand national standard of 0.25 mg As L(-1) for water and 27 mg As kg soil(-1) for the soil. Arsenic accumulation in the biomass of 5 aquatic plants at the biowetland ponds ranged from 123.83 to 280.53 mg As kgPlant(-1). Regarding the result of regression analysis (R (2) = 0.474 to 0.954), high concentrations of organic matter and other soluble ions as well as high pH value in the sediment could significantly enhance the removal of soluble arsenic in the wetland ponds. From the regression equation of accumulated arsenic concentration in each aquatic plant, Eichhornia crassipes (Mart.) Solms. (R (2) = 0.954), Ipomoea aquatica Forsk. (R (2) = 0.850), and Typha angustifolia (L.) (R (2) = 0.841) were found to be preferable arsenic removers for wastewater treatment pond in the condition of low Eh value and high content of solid phase EC and phosphorus. On the other hand, Canna glauca (L.) (R (2) = 0.749) appeared to be favorable arsenic accumulator for the treatment pond in the condition of high Eh value and high concentration of soluble EC. PMID:19455397

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

    NASA Technical Reports Server (NTRS)

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

    1990-01-01

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

  5. Absolute magnitude calibration using trigonometric parallax - Incomplete, spectroscopic samples

    NASA Technical Reports Server (NTRS)

    Ratnatunga, Kavan U.; Casertano, Stefano

    1991-01-01

    A new numerical algorithm is used to calibrate the absolute magnitude of spectroscopically selected stars from their observed trigonometric parallax. This procedure, based on maximum-likelihood estimation, can retrieve unbiased estimates of the intrinsic absolute 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 accuracy 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.

  6. Flow rate calibration for absolute cell counting rationale and design.

    PubMed

    Walker, Clare; Barnett, David

    2006-05-01

    There is a need for absolute leukocyte enumeration in the clinical setting, and accurate, reliable (and affordable) technology to determine absolute leukocyte counts has been developed. Such technology includes single platform and dual platform approaches. Derivations of these counts commonly incorporate the addition of a known number of latex microsphere beads to a blood sample, although it has been suggested that the addition of beads to a sample may only be required to act as an internal quality control procedure for assessing the pipetting error. This unit provides the technical details for undertaking flow rate calibration that obviates the need to add reference beads to each sample. It is envisaged that this report will provide the basis for subsequent clinical evaluations of this novel approach. PMID:18770842

  7. Photometer calibration error using extended standard sources

    NASA Technical Reports Server (NTRS)

    Torr, M. R.; Hays, P. B.; Kennedy, B. C.; Torr, D. G.

    1976-01-01

    As part of a project to compare measurements of the night airglow made by the visible airglow experiment on the Atmospheric Explorer-C satellite, the standard light sources of several airglow observatories were compared with the standard source used in the absolute calibration of the satellite photometer. In the course of the comparison, it has been found that serious calibration errors (up to a factor of two) can arise when a calibration source with a reflecting surface is placed close to an interference filter. For reliable absolute calibration, the source should be located at a distance of at least five filter radii from the interference filter.

  8. Sun compass error model

    NASA Technical Reports Server (NTRS)

    Blucker, T. J.; Ferry, W. W.

    1971-01-01

    An error model is described for the Apollo 15 sun compass, a contingency navigational device. Field test data are presented along with significant results of the test. The errors reported include a random error resulting from tilt in leveling the sun compass, a random error because of observer sighting inaccuracies, a bias error because of mean tilt in compass leveling, a bias error in the sun compass itself, and a bias error because the device is leveled to the local terrain slope.

  9. Absolute oral bioavailability of ciprofloxacin.

    PubMed

    Drusano, G L; Standiford, H C; Plaisance, K; Forrest, A; Leslie, J; Caldwell, J

    1986-09-01

    We evaluated the absolute bioavailability of ciprofloxacin, a new quinoline carboxylic acid, in 12 healthy male volunteers. Doses of 200 mg were given to each of the volunteers in a randomized, crossover manner 1 week apart orally and as a 10-min intravenous infusion. Half-lives (mean +/- standard deviation) for the intravenous and oral administration arms were 4.2 +/- 0.77 and 4.11 +/- 0.74 h, respectively. The serum clearance rate averaged 28.5 +/- 4.7 liters/h per 1.73 m2 for the intravenous administration arm. The renal clearance rate accounted for approximately 60% of the corresponding serum clearance rate and was 16.9 +/- 3.0 liters/h per 1.73 m2 for the intravenous arm and 17.0 +/- 2.86 liters/h per 1.73 m2 for the oral administration arm. Absorption was rapid, with peak concentrations in serum occurring at 0.71 +/- 0.15 h. Bioavailability, defined as the ratio of the area under the curve from 0 h to infinity for the oral to the intravenous dose, was 69 +/- 7%. We conclude that ciprofloxacin is rapidly absorbed and reliably bioavailable in these healthy volunteers. Further studies with ciprofloxacin should be undertaken in target patient populations under actual clinical circumstances. PMID:3777908

  10. Absolute Instability in Coupled-Cavity TWTs

    NASA Astrophysics Data System (ADS)

    Hung, D. M. H.; Rittersdorf, I. M.; Zhang, Peng; Lau, Y. Y.; Simon, D. H.; Gilgenbach, R. M.; Chernin, D.; Antonsen, T. M., Jr.

    2014-10-01

    This paper will present results of our analysis of absolute instability in a coupled-cavity traveling wave tube (TWT). The structure mode at the lower and upper band edges are respectively approximated by a hyperbola in the (omega, k) plane. When the Briggs-Bers criterion is applied, a threshold current for onset of absolute instability is observed at the upper band edge, but not the lower band edge. The nonexistence of absolute instability at the lower band edge is mathematically similar to the nonexistence of absolute instability that we recently demonstrated for a dielectric TWT. The existence of absolute instability at the upper band edge is mathematically similar to the existence of absolute instability in a gyroton traveling wave amplifier. These interesting observations will be discussed, and the practical implications will be explored. This work was supported by AFOSR, ONR, and L-3 Communications Electron Devices.

  11. Testing and evaluation of thermal cameras for absolute temperature measurement

    NASA Astrophysics Data System (ADS)

    Chrzanowski, Krzysztof; Fischer, Joachim; Matyszkiel, Robert

    2000-09-01

    The accuracy of temperature measurement is the most important criterion for the evaluation of thermal cameras used in applications requiring absolute temperature measurement. All the main international metrological organizations currently propose a parameter called uncertainty as a measure of measurement accuracy. We propose a set of parameters for the characterization of thermal measurement cameras. It is shown that if these parameters are known, then it is possible to determine the uncertainty of temperature measurement due to only the internal errors of these cameras. Values of this uncertainty can be used as an objective criterion for comparisons of different thermal measurement cameras.

  12. Absolute negative mobility of interacting Brownian particles

    NASA Astrophysics Data System (ADS)

    Ou, Ya-li; Hu, Cai-tian; Wu, Jian-chun; Ai, Bao-quan

    2015-12-01

    Transport of interacting Brownian particles in a periodic potential is investigated in the presence of an ac force and a dc force. From Brownian dynamic simulations, we find that both the interaction between particles and the thermal fluctuations play key roles in the absolute negative mobility (the particle noisily moves backwards against a small constant bias). When no the interaction acts, there is only one region where the absolute negative mobility occurs. In the presence of the interaction, the absolute negative mobility may appear in multiple regions. The weak interaction can be helpful for the absolute negative mobility, while the strong interaction has a destructive impact on it.

  13. Potential Role of Acetyl-CoA Synthetase (acs) and Malate Dehydrogenase (mae) in the Evolution of the Acetate Switch in Bacteria and Archaea

    PubMed Central

    Barnhart, Elliott P.; McClure, Marcella A.; Johnson, Kiki; Cleveland, Sean; Hunt, Kristopher A.; Fields, Matthew W.

    2015-01-01

    Although many Archaea have AMP-Acs (acetyl-coenzyme A synthetase) and ADP-Acs, the extant methanogenic genus Methanosarcina is the only identified Archaeal genus that can utilize acetate via acetate kinase (Ack) and phosphotransacetylase (Pta). Despite the importance of ack as the potential urkinase in the ASKHA phosphotransferase superfamily, an origin hypothesis does not exist for the acetate kinase in Bacteria, Archaea, or Eukarya. Here we demonstrate that Archaeal AMP-Acs and ADP-Acs contain paralogous ATPase motifs previously identified in Ack, which demonstrate a novel relation between these proteins in Archaea. The identification of ATPase motif conservation and resulting structural features in AMP- and ADP-acetyl-CoA synthetase proteins in this study expand the ASKHA superfamily to include acetyl-CoA synthetase. Additional phylogenetic analysis showed that Pta and MaeB sequences had a common ancestor, and that the Pta lineage within the halophilc archaea was an ancestral lineage. These results suggested that divergence of a duplicated maeB within an ancient halophilic, archaeal lineage formed a putative pta ancestor. These results provide a potential scenario for the establishment of the Ack/Pta pathway and provide novel insight into the evolution of acetate metabolism for all three domains of life. PMID:26235787

  14. Potential Role of Acetyl-CoA Synthetase (acs) and Malate Dehydrogenase (mae) in the Evolution of the Acetate Switch in Bacteria and Archaea

    DOE PAGESBeta

    Barnhart, Elliott P.; McClure, Marcella A.; Johnson, Kiki; Cleveland, Sean; Hunt, Kristopher A.; Fields, Matthew W.

    2015-08-03

    Although many Archaea have AMP-Acs (acetyl-coenzyme A synthetase) and ADP-Acs, the extant methanogenic genus Methanosarcina is the only identified Archaeal genus that can utilize acetate via acetate kinase (Ack) and phosphotransacetylase (Pta). Despite the importance of ack as the potential urkinase in the ASKHA phosphotransferase superfamily, an origin hypothesis does not exist for the acetate kinase in Bacteria, Archaea, or Eukarya. Here we demonstrate that Archaeal AMP-Acs and ADP-Acs contain paralogous ATPase motifs previously identified in Ack, which demonstrate a novel relation between these proteins in Archaea. The identification of ATPase motif conservation and resulting structural features in AMP- andmore » ADP-acetyl-CoA synthetase proteins in this study expand the ASKHA superfamily to include acetyl-CoA synthetase. Additional phylogenetic analysis showed that Pta and MaeB sequences had a common ancestor, and that the Pta lineage within the halophilc archaea was an ancestral lineage. Lastly, these results suggested that divergence of a duplicated maeB within an ancient halophilic, archaeal lineage formed a putative pta ancestor. These results provide a potential scenario for the establishment of the Ack/Pta pathway and provide novel insight into the evolution of acetate metabolism for all three domains of life.« less

  15. Potential Role of Acetyl-CoA Synthetase (acs) and Malate Dehydrogenase (mae) in the Evolution of the Acetate Switch in Bacteria and Archaea

    SciTech Connect

    Barnhart, Elliott P.; McClure, Marcella A.; Johnson, Kiki; Cleveland, Sean; Hunt, Kristopher A.; Fields, Matthew W.

    2015-08-03

    Although many Archaea have AMP-Acs (acetyl-coenzyme A synthetase) and ADP-Acs, the extant methanogenic genus Methanosarcina is the only identified Archaeal genus that can utilize acetate via acetate kinase (Ack) and phosphotransacetylase (Pta). Despite the importance of ack as the potential urkinase in the ASKHA phosphotransferase superfamily, an origin hypothesis does not exist for the acetate kinase in Bacteria, Archaea, or Eukarya. Here we demonstrate that Archaeal AMP-Acs and ADP-Acs contain paralogous ATPase motifs previously identified in Ack, which demonstrate a novel relation between these proteins in Archaea. The identification of ATPase motif conservation and resulting structural features in AMP- and ADP-acetyl-CoA synthetase proteins in this study expand the ASKHA superfamily to include acetyl-CoA synthetase. Additional phylogenetic analysis showed that Pta and MaeB sequences had a common ancestor, and that the Pta lineage within the halophilc archaea was an ancestral lineage. Lastly, these results suggested that divergence of a duplicated maeB within an ancient halophilic, archaeal lineage formed a putative pta ancestor. These results provide a potential scenario for the establishment of the Ack/Pta pathway and provide novel insight into the evolution of acetate metabolism for all three domains of life.

  16. Determination of organophosphorus fire retardants and plasticizers in wastewater samples using MAE-SPME with GC-ICPMS and GC-TOFMS detection.

    PubMed

    Ellis, Jenny; Shah, Monika; Kubachka, Kevin M; Caruso, Joseph A

    2007-12-01

    Determination of organophosphorus fire retardants and plasticizers at trace levels in wastewater is described. In this work, microwave assisted extraction (MAE) and solid-phase microextraction (SPME) are used for sample preparation to extract and preconcentrate the analytes, followed by analysis by gas chromatography coupled to inductively coupled plasma mass spectrometry (GC-ICP-MS) for phosphorus-specific detection. Gas chromatography coupled to time of flight mass spectrometry (GC-TOF-MS) was used to confirm the organphosphorus fire retardants in wastewater. The detection limits of organophosphorus fire retardants (OPFRs) were 29 ng L(-1) for tri-n-butyl phosphate (TnBP), 45 ng for L(-1) for tris(2-butoxyethyl)phosphate (TBEP), and 50 ng L(-1) for tris(2-ethylhexyl)phosphate (TEHP). Optimized extraction conditions were performed at 65 degrees C for 30 min and with 10% NaCl. Application of MAE during the sample preparation prior to the SPME allowed the detection of tris(2-ethylhexyl) phosphate, which has been difficult to determine in previous work. Application of the method to wastewater samples resulted in detecting 3.1 microg L(-1) P from TnBP, 5.0 microg L(-1) P from TBEP, and 4.0 microg L(-1) P from TEHP. The presence of these compounds were also confirmed by SPME-GC-TOF-MS. PMID:18049771

  17. Direct comparisons between absolute and relative geomagnetic paleointensities: Absolute calibration of a relative paleointensity stack

    NASA Astrophysics Data System (ADS)

    Mochizuki, N.; Yamamoto, Y.; Hatakeyama, T.; Shibuya, H.

    2013-12-01

    Absolute geomagnetic paleointensities (APIs) have been estimated from igneous rocks, while relative paleomagnetic intensities (RPIs) have been reported from sediment cores. These two datasets have been treated separately, as correlations between APIs and RPIs are difficult on account of age uncertainties. High-resolution RPI stacks have been constructed from globally distributed sediment cores with high sedimentation rates. Previous studies often assumed that the RPI stacks have a linear relationship with geomagnetic axial dipole moments, and calibrated the RPI values to API values. However, the assumption of a linear relationship between APIs and RPIs has not been evaluated. Also, a quantitative calibration method for the RPI is lacking. We present a procedure for directly comparing API and RPI stacks, thus allowing reliable calibrations of RPIs. Direct comparisons between APIs and RPIs were conducted with virtually no associated age errors using both tephrochronologic correlations and RPI minima. Using the stratigraphic positions of tephra layers in oxygen isotope stratigraphic records, we directly compared the RPIs and APIs reported from welded tuffs contemporaneously extruded with the tephra layers. In addition, RPI minima during geomagnetic reversals and excursions were compared with APIs corresponding to the reversals and excursions. The comparison of APIs and RPIs at these exact points allowed a reliable calibration of the RPI values. We applied this direct comparison procedure to the global RPI stack PISO-1500. For six independent calibration points, virtual axial dipole moments (VADMs) from the corresponding APIs and RPIs of the PISO-1500 stack showed a near-linear relationship. On the basis of the linear relationship, RPIs of the stack were successfully calibrated to the VADMs. The direct comparison procedure provides an absolute calibration method that will contribute to the recovery of temporal variations and distributions of geomagnetic axial dipole

  18. Remediating Common Math Errors.

    ERIC Educational Resources Information Center

    Wagner, Rudolph F.

    1981-01-01

    Explanations and remediation suggestions for five types of mathematics errors due either to perceptual or cognitive difficulties are given. Error types include directionality problems, mirror writing, visually misperceived signs, diagnosed directionality problems, and mixed process errors. (CL)

  19. Medication administration errors for older people in long-term residential care

    PubMed Central

    2011-01-01

    Background Older people in long-term residential care are at increased risk of medication prescribing and administration errors. The main aim of this study was to measure the incidence of medication administration errors in nursing and residential homes using a barcode medication administration (BCMA) system. Methods A prospective study was conducted in 13 care homes (9 residential and 4 nursing). Data on all medication administrations for a cohort of 345 older residents were recorded in real-time using a disguised observation technique. Every attempt by social care and nursing staff to administer medication over a 3-month observation period was analysed using BCMA records to determine the incidence and types of potential medication administration errors (MAEs) and whether errors were averted. Error classifications included attempts to administer medication at the wrong time, to the wrong person or discontinued medication. Further analysis compared data for residential and nursing homes. In addition, staff were surveyed prior to BCMA system implementation to assess their awareness of administration errors. Results A total of 188,249 medication administration attempts were analysed using BCMA data. Typically each resident was receiving nine different drugs and was exposed to 206 medication administration episodes every month. During the observation period, 2,289 potential MAEs were recorded for the 345 residents; 90% of residents were exposed to at least one error. The most common (n = 1,021, 45% of errors) was attempting to give medication at the wrong time. Over the 3-month observation period, half (52%) of residents were exposed to a serious error such as attempting to give medication to the wrong resident. Error incidence rates were 1.43 as high (95% CI 1.32-1.56 p < 0.001) in nursing homes as in residential homes. The level of non-compliance with system alerts was very low in both settings (0.075% of administrations). The pre-study survey revealed that only 12

  20. Updated Absolute Flux Calibration of the COS FUV Modes

    NASA Astrophysics Data System (ADS)

    Massa, D.; Ely, J.; Osten, R.; Penton, S.; Aloisi, A.; Bostroem, A.; Roman-Duval, J.; Proffitt, C.

    2014-03-01

    We present newly derived point source absolute 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 accuracy of the absolute 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 time at which the flux calibration data were obtained; the accuracy of the flux calibration at other times can be affected by errors in the time dependent sensitivity (TDS) correction.

  1. [Error factors in spirometry].

    PubMed

    Quadrelli, S A; Montiel, G C; Roncoroni, A J

    1994-01-01

    Spirometry is the more frequently used method to estimate pulmonary function in the clinical laboratory. It is important to comply with technical requisites to approximate the real values sought as well as adequate interpretation of results. Recommendations are made to establish: 1--quality control 2--define abnormality 3--classify the change from normal and its degree 4--define reversibility. In relation to quality control several criteria are pointed out such as end of the test, back-extrapolation and extrapolated volume in order to delineate most common errors. Daily calibration is advised. Inspection of graphical records of the test is mandatory. The limitations to the common use of 80% of predicted values to establish abnormality is stressed. The reasons for employing 95% confidence limits are detailed. It is important to select the reference values equation (in view of the differences in predicted values). It is advisable to validate the selection with local population normal values. In relation to the definition of the defect as restrictive or obstructive, the limitations of vital capacity (VC) to establish restriction, when obstruction is also present, are defined. Also the limitations of maximal mid-expiratory flow 25-75 (FMF 25-75) as an isolated marker of obstruction. Finally the qualities of forced expiratory volume in 1 sec (VEF1) and the difficulties with other indicators (CVF, FMF 25-75, VEF1/CVF) to estimate reversibility after bronchodilators are evaluated. The value of different methods used to define reversibility (% of change in initial value, absolute change or % of predicted), is commented. Clinical spirometric studies in order to be valuable should be performed with the same technical rigour as any other more complex studies. PMID:7990690

  2. Inequalities, Absolute Value, and Logical Connectives.

    ERIC Educational Resources Information Center

    Parish, Charles R.

    1992-01-01

    Presents an approach to the concept of absolute value that alleviates students' problems with the traditional definition and the use of logical connectives in solving related problems. Uses a model that maps numbers from a horizontal number line to a vertical ray originating from the origin. Provides examples solving absolute value equations and…

  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. Monolithically integrated absolute frequency comb laser system

    DOEpatents

    Wanke, Michael C.

    2016-07-12

    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 absolute frequency without the need of a frequency-comb synthesizer. The monolithic, absolute frequency comb can provide a THz frequency reference and tool for high-resolution broad band spectroscopy.

  5. Introducing the Mean Absolute Deviation "Effect" Size

    ERIC Educational Resources Information Center

    Gorard, Stephen

    2015-01-01

    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 absolute deviation as a measure of variation, as opposed to the more complex standard deviation. The mean absolute deviation is easier to use and understand, and more tolerant of extreme…

  6. Investigating Absolute Value: A Real World Application

    ERIC Educational Resources Information Center

    Kidd, Margaret; Pagni, David

    2009-01-01

    Making connections between various representations is important in mathematics. In this article, the authors discuss the numeric, algebraic, and graphical representations of sums of absolute values of linear functions. The initial explanations are accessible to all students who have experience graphing and who understand that absolute value simply…

  7. Absolute Income, Relative Income, and Happiness

    ERIC Educational Resources Information Center

    Ball, Richard; Chernova, Kateryna

    2008-01-01

    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 absolute terms, and (ii) the level of her income relative to other people in her country. The main findings are that (i) both absolute and relative income are positively and significantly…

  8. Absolute length measurement using manually decided stereo correspondence for endoscopy

    NASA Astrophysics Data System (ADS)

    Sasaki, M.; Koishi, T.; Nakaguchi, T.; Tsumura, N.; Miyake, Y.

    2009-02-01

    In recent years, various kinds of endoscope have been developed and widely used to endoscopic biopsy, endoscopic operation and endoscopy. The size of the inflammatory part is important to determine a method of medical treatment. However, it is not easy to measure absolute size of inflammatory part such as ulcer, cancer and polyp from the endoscopic image. Therefore, it is required measuring the size of those part in endoscopy. In this paper, we propose a new method to measure the absolute length in a straight line between arbitrary two points based on the photogrammetry using endoscope with magnetic tracking sensor which gives camera position and angle. In this method, the stereo-corresponding points between two endoscopic images are determined by the endoscopist without any apparatus of projection and calculation to find the stereo correspondences, then the absolute length can be calculated on the basis of the photogrammetry. The evaluation experiment using a checkerboard showed that the errors of the measurements are less than 2% of the target length when the baseline is sufficiently-long.

  9. Absolute instability of the Gaussian wake profile

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.; Aggarwal, Arun K.

    1987-01-01

    Linear parallel-flow stability theory has been used to investigate the effect of viscosity on the local absolute instability of a family of wake profiles with a Gaussian velocity distribution. The type of local instability, i.e., convective or absolute, 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. Absolute 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 absolute instability with decreasing wake Reynolds number. If backflow is not allowed, absolute instability does not occur for wake Reynolds numbers smaller than about 38.

  10. Measurement error analysis of taxi meter

    NASA Astrophysics Data System (ADS)

    He, Hong; Li, Dan; Li, Hang; Zhang, Da-Jian; Hou, Ming-Feng; Zhang, Shi-pu

    2011-12-01

    The error test of the taximeter is divided into two aspects: (1) the test about time error of the taximeter (2) distance test about the usage error of the machine. The paper first gives the working principle of the meter and the principle of error verification device. Based on JJG517 - 2009 "Taximeter Verification Regulation ", the paper focuses on analyzing the machine error and test error of taxi meter. And the detect methods of time error and distance error are discussed as well. In the same conditions, standard uncertainty components (Class A) are evaluated, while in different conditions, standard uncertainty components (Class B) are also evaluated and measured repeatedly. By the comparison and analysis of the results, the meter accords with JJG517-2009, "Taximeter Verification Regulation ", thereby it improves the accuracy and efficiency largely. In actual situation, the meter not only makes up the lack of accuracy, but also makes sure the deal between drivers and passengers fair. Absolutely it enriches the value of the taxi as a way of transportation.

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

    PubMed

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

    2015-07-01

    Optical thickness is a fundamental characteristic of an optical component. A measurement method combining discrete Fourier-transform (DFT) analysis and a phase-shifting technique gives an appropriate value for the absolute optical thickness of a transparent plate. However, there is a systematic error caused by the nonlinearity of the phase-shifting technique. In this research the absolute optical-thickness distribution of mask blank glass was measured using DFT and wavelength-tuning Fizeau interferometry without using sensitive phase-shifting techniques. The error occurring during the DFT analysis was compensated for by using the unwrapping correlation. The experimental results indicated that the absolute optical thickness of mask glass was measured with an accuracy of 5 nm. PMID:26125394

  12. Absolute flatness testing of skip-flat interferometry by matrix analysis in polar coordinates.

    PubMed

    Han, Zhi-Gang; Yin, Lu; Chen, Lei; Zhu, Ri-Hong

    2016-03-20

    A new method utilizing matrix analysis in polar coordinates has been presented for absolute testing of skip-flat interferometry. The retrieval of the absolute 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 accuracy of the order of 0.01 nm RMS. The absolute 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 absolute testing. PMID:27140578

  13. Absolute optical instruments without spherical symmetry

    NASA Astrophysics Data System (ADS)

    Tyc, Tomáš; Dao, H. L.; Danner, Aaron J.

    2015-11-01

    Until now, the known set of absolute optical instruments has been limited to those containing high levels of symmetry. Here, we demonstrate a method of mathematically constructing refractive index profiles that result in asymmetric absolute optical instruments. The method is based on the analogy between geometrical optics and classical mechanics and employs Lagrangians that separate in Cartesian coordinates. In addition, our method can be used to construct the index profiles of most previously known absolute optical instruments, as well as infinitely many different ones.

  14. Determination and error analysis of emittance and spectral emittance measurements by remote sensing

    NASA Technical Reports Server (NTRS)

    Dejesusparada, N. (Principal Investigator); Kumar, R.

    1977-01-01

    The author has identified the following significant results. From the theory of remote sensing of surface temperatures, an equation of the upper bound of absolute error of emittance was determined. It showed that the absolute error decreased with an increase in contact temperature, whereas, it increased with an increase in environmental integrated radiant flux density. Change in emittance had little effect on the absolute error. A plot of the difference between temperature and band radiance temperature vs. emittance was provided for the wavelength intervals: 4.5 to 5.5 microns, 8 to 13.5 microns, and 10.2 to 12.5 microns.

  15. On-orbit absolute radiance standard for the next generation of IR remote sensing instruments

    NASA Astrophysics Data System (ADS)

    Best, Fred A.; Adler, Douglas P.; Pettersen, Claire; Revercomb, Henry E.; Gero, P. Jonathan; Taylor, Joseph K.; Knuteson, Robert O.; Perepezko, John H.

    2012-11-01

    The next generation of infrared remote sensing satellite instrumentation, including climate benchmark missions will require better absolute measurement accuracy than now available, and will most certainly rely on the emerging capability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances with an absolute 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 absolute temperature uncertainties of better than 0.045K (k=3). Key elements of an On-Orbit Absolute Radiance Standard (OARS) meeting these stringent requirements have been demonstrated in the laboratory at the University of Wisconsin (UW) and refined under the NASA Instrument Incubator Program (IIP). This work recently culminated with an integrated subsystem that was used in the laboratory to demonstrate end-to-end radiometric accuracy verification for the UW Absolute Radiance Interferometer. Along with an overview of the design, we present details of a key underlying technology of the OARS that provides on-orbit absolute temperature calibration using the transient melt signatures of small quantities (<1g) of reference materials (gallium, water, and mercury) imbedded in the blackbody cavity. In addition we present performance data from the laboratory testing of the OARS.

  16. Timing of metamorphism of the Lansang gneiss and implications for left-lateral motion along the Mae Ping (Wang Chao) strike-slip fault, Thailand

    NASA Astrophysics Data System (ADS)

    Palin, R. M.; Searle, M. P.; Morley, C. K.; Charusiri, P.; Horstwood, M. S. A.; Roberts, N. M. W.

    2013-10-01

    The Mae Ping fault (MPF), western Thailand, exhibits dominantly left-lateral strike-slip motion and stretches for >600 km, reportedly branching off the right-lateral Sagaing fault in Myanmar and extending southeast towards Cambodia. Previous studies have suggested that the fault assisted the large-scale extrusion of Sundaland that occurred during the Late Eocene-Early Oligocene, with a geological offset of ˜120-150 km estimated from displaced high-grade gneisses and granites of the Chiang Mai-Lincang belt. Exposures of high-grade orthogneiss in the Lansang National Park, part of this belt, locally contain strong mylonitic textures and are bounded by strike-slip ductile shear zones and brittle faults. Geochronological analysis of monazite from a sample of sheared biotite-K-feldspar orthogneiss suggests two episodes of crystallization, with core regions documenting Th-Pb ages between c. 123 and c. 114 Ma and rim regions documenting a significantly younger age range between c. 45-37 Ma. These data are interpreted to represent possible magmatic protolith emplacement for the Lansang orthogneiss during the Early Cretaceous, with a later episode of metamorphism occurring during the Eocene. Textural relationships provided by in situ analysis suggest that ductile shearing along the MPF occurred during the latter stages of, or after, this metamorphic event. In addition, monazite analyzed from an undeformed garnet-two-mica granite dyke intruding metamorphic units at Bhumipol Lake outside of the Mae Ping shear zone produced a Th-Pb age of 66.2 ± 1.6 Ma. This age is interpreted to date the timing of dyke emplacement, implying that the MPF cuts through earlier formed magmatic and high-grade metamorphic rocks. These new data, when combined with regional mapping and earlier geochronological work, show that neither metamorphism, nor regional cooling, was directly related to strike-slip motion.

  17. Absolute magnitudes of trans-neptunian objects

    NASA Astrophysics Data System (ADS)

    Duffard, R.; Alvarez-candal, A.; Pinilla-Alonso, N.; Ortiz, J. L.; Morales, N.; Santos-Sanz, P.; Thirouin, A.

    2015-10-01

    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 absolute magnitudes are needed to constrain diameters and albedos. Our objective is to measure accurate absolute 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 time. 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 absolute 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 absolute magnitudes.

  18. A New Gimmick for Assigning Absolute Configuration.

    ERIC Educational Resources Information Center

    Ayorinde, F. O.

    1983-01-01

    A five-step procedure is provided to help students in making the assignment absolute configuration less bothersome. Examples for both single (2-butanol) and multi-chiral carbon (3-chloro-2-butanol) molecules are included. (JN)

  19. Determination of colchicine and O-demethylated metabolites in decomposed skeletal tissues by microwave assisted extraction, microplate solid phase extraction and ultra-high performance liquid chromatography (MAE-MPSPE-UHPLC).

    PubMed

    Watterson, J H; Imfeld, A B; Cornthwaite, H C

    2014-06-01

    Microwave assisted extraction (MAE) followed by microplate solid phase extraction (MPSPE) coupled with ultra high performance liquid chromatography (UHPLC) for the semi-quantitative determination of colchicine, 3-demethyl colchicine and 2-demethyl colchicine in postmortem rat bone is described. Rats (n=4) received 50mg/kg colchicine (i.p), and euthanized by CO2 asphyxiation. Remains decomposed to skeleton outdoors and vertebral bones were collected cleaned, and ground to a fine powder. Powdered bone underwent MAE using methanol in a closed microwave system, followed by MPSPE and analysis using UHPLC-PDA. MAE analyte stability was assessed and found to be stable for at least 60 min irradiation time. The majority (>95%) of each analyte was recovered after 15 min. The MPSPE-UHPLC method was linear between 10 and 2,000 ng/mL, with coefficients of variation <20% in triplicate analysis, with a limit of detection of 10 ng/mL for each of the three analytes. Following MAE for 30 min (80°C, 1200W), MPSPE-UHPLC analysis of vertebral bone of colchicine-exposed rats detected colchicine (1.8-4.1 μg/g), 3-demethyl colchicine (0.77-1.8 μg/g) and 2-demethyl colchicine (0.43-0.80 μg/g) in all samples assayed. PMID:24799069

  20. Oversight of Student Loan Marketing Association (Sallie Mae). Hearing Before the Subcommittee on Education, Arts and Humanities of the Committee on Labor and Human Resources. United States Senate, Ninety-Seventh Congress, Second Session.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. Senate Committee on Labor and Human Resources.

    Hearings concerning the activities of the Student Loan Marketing Association (Sallie Mae) are presented. Attention is focused on a request for an exemption under federal priority for recovering money owed the Association in the event that it files for liquidation or reorganization in the future under the Bankruptcy Act. It is noted that two goals…

  1. Hearing on the Reauthorization of the Higher Education Act of 1965; Sallie Mae--Safety and Soundness. Hearing before the Subcommittee on Postsecondary Education of the Committee on Education and Labor. House of Representatives, One Hundred Second Congress, First Session.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. House Subcommittee on Postsecondary Education.

    As part of a series of hearings on the reauthorization of the Higher Education Act of 1965, testimony was heard on the safety and soundness of the Student Loan Marketing Association (Sallie Mae). Witnesses discussed many issues surrounding financial oversight of federal agencies and financial risk to the taxpayer through the potential failure of…

  2. Field error lottery

    SciTech Connect

    Elliott, C.J.; McVey, B. ); Quimby, D.C. )

    1990-01-01

    The level of field errors in an FEL is an important determinant of its performance. We have computed 3D performance of a large laser subsystem subjected to field errors of various types. These calculations have been guided by simple models such as SWOOP. The technique of choice is utilization of the FELEX free electron laser code that now possesses extensive engineering capabilities. Modeling includes the ability to establish tolerances of various types: fast and slow scale field bowing, field error level, beam position monitor error level, gap errors, defocusing errors, energy slew, displacement and pointing errors. Many effects of these errors on relative gain and relative power extraction are displayed and are the essential elements of determining an error budget. The random errors also depend on the particular random number seed used in the calculation. The simultaneous display of the performance versus error level of cases with multiple seeds illustrates the variations attributable to stochasticity of this model. All these errors are evaluated numerically for comprehensive engineering of the system. In particular, gap errors are found to place requirements beyond mechanical tolerances of {plus minus}25{mu}m, and amelioration of these may occur by a procedure utilizing direct measurement of the magnetic fields at assembly time. 4 refs., 12 figs.

  3. Privatization of Sallie Mae and Connie Lee. Hearing on Examining Proposed Legislation To Allow for an Orderly Transition of the Student Loan Marketing Association (Sallie Mae) to Private Status...and a Proposal to Privatize the College Construction Loan Insurance Association (Connie Lee) before the Subcommittee on Education, Arts and Humanities of the Committee on Labor and Human Resources. United States Senate, One Hundred Fourth Congress, First Session.

    ERIC Educational Resources Information Center

    Congress of the U.S., Washington, DC. Senate Committee on Labor and Human Resources.

    The Subcommittee heard testimony from seven witnesses and statements from three senators on whether or not it is in the Federal Government's best interest to divest itself of the Student Loan Marketing Association (Sallie Mae), and the College Construction Loan Insurance Association (Connie Lee). Lawrence A. Hough of the Student Loan Marketing…

  4. Inborn errors of metabolism

    MedlinePlus

    Metabolism - inborn errors of ... Bodamer OA. Approach to inborn errors of metabolism. In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 205. Rezvani I, Rezvani G. An ...

  5. Landsat-7 ETM+ radiometric stability and absolute calibration

    USGS Publications Warehouse

    Markham, B.L.; Barker, J.L.; Barsi, J.A.; Kaita, E.; Thome, K.J.; Helder, D.L.; Palluconi, Frank Don; Schott, J.R.; Scaramuzza, P.

    2002-01-01

    Launched in April 1999, the Landsat-7 ETM+ instrument is in its fourth year of operation. The quality of the acquired calibrated imagery continues to be high, especially with respect to its three most important radiometric performance parameters: reflective band instrument stability to better than ??1%, reflective band absolute calibration to better than ??5%, and thermal band absolute calibration to better than ??0.6 K. The ETM+ instrument has been the most stable of any of the Landsat instruments, in both the reflective and thermal channels. To date, the best on-board calibration source for the reflective bands has been the Full Aperture Solar Calibrator, which has indicated changes of at most -1.8% to -2.0% (95% C.I.) change per year in the ETM+ gain (band 4). However, this change is believed to be caused by changes in the solar diffuser panel, as opposed to a change in the instrument's gain. This belief is based partially on ground observations, which bound the changes in gain in band 4 at -0.7% to +1.5%. Also, ETM+ stability is indicated by the monitoring of desert targets. These image-based results for four Saharan and Arabian sites, for a collection of 35 scenes over the three years since launch, bound the gain change at -0.7% to +0.5% in band 4. Thermal calibration from ground observations revealed an offset error of +0.31 W/m 2 sr um soon after launch. This offset was corrected within the U. S. ground processing system at EROS Data Center on 21-Dec-00, and since then, the band 6 on-board calibration has indicated changes of at most +0.02% to +0.04% (95% C.I.) per year. The latest ground observations have detected no remaining offset error with an RMS error of ??0.6 K. The stability and absolute calibration of the Landsat-7 ETM+ sensor make it an ideal candidate to be used as a reference source for radiometric cross-calibrating to other land remote sensing satellite systems.

  6. Correction due to the finite speed of light in absolute gravimeters Correction due to the finite speed of light in absolute gravimeters

    NASA Astrophysics Data System (ADS)

    Nagornyi, V. D.; Zanimonskiy, Y. M.; Zanimonskiy, Y. Y.

    2011-06-01

    Equations (45) and (47) in our paper [1] in this issue have incorrect sign and should read \\tilde T_i=T_i+{b\\mp S_i\\over c},\\cr\\tilde T_i=T_i\\mp {S_i\\over c}. The error traces back to our formula (3), inherited from the paper [2]. According to the technical documentation [3, 4], the formula (3) is implemented by several commercially available instruments. An incorrect sign would cause a bias of about 20 µGal not known for these instruments, which probably indicates that the documentation incorrectly reflects the implemented measurement equation. Our attention to the error was drawn by the paper [5], also in this issue, where the sign is mentioned correctly. References [1] Nagornyi V D, Zanimonskiy Y M and Zanimonskiy Y Y 2011 Correction due to the finite speed of light in absolute gravimeters Metrologia 48 101-13 [2] Niebauer T M, Sasagawa G S, Faller J E, Hilt R and Klopping F 1995 A new generation of absolute gravimeters Metrologia 32 159-80 [3] Micro-g LaCoste, Inc. 2006 FG5 Absolute Gravimeter Users Manual [4] Micro-g LaCoste, Inc. 2007 g7 Users Manual [5] Niebauer T M, Billson R, Ellis B, Mason B, van Westrum D and Klopping F 2011 Simultaneous gravity and gradient measurements from a recoil-compensated absolute gravimeter Metrologia 48 154-63

  7. [Paradigm errors in the old biomedical science].

    PubMed

    Skurvydas, Albertas

    2008-01-01

    The aim of this article was to review the basic drawbacks of the deterministic and reductionistic thinking in biomedical science and to provide ways for dealing with them. The present paradigm of research in biomedical science has not got rid of the errors of the old science yet, i.e. the errors of absolute determinism and reductionism. These errors restrict the view and thinking of scholars engaged in the studies of complex and dynamic phenomena and mechanisms. Recently, discussions on science paradigm aimed at spreading the new science paradigm that of complex dynamic systems as well as chaos theory are in progress all over the world. It is for the nearest future to show which of the two, the old or the new science, will be the winner. We have come to the main conclusion that deterministic and reductionistic thinking applied in improper way can cause substantial damage rather than prove benefits for biomedicine science. PMID:18541951

  8. Programming Errors in APL.

    ERIC Educational Resources Information Center

    Kearsley, Greg P.

    This paper discusses and provides some preliminary data on errors in APL programming. Data were obtained by analyzing listings of 148 complete and partial APL sessions collected from student terminal rooms at the University of Alberta. Frequencies of errors for the various error messages are tabulated. The data, however, are limited because they…

  9. Jasminum flexile flower absolute from India--a detailed comparison with three other jasmine absolutes.

    PubMed

    Braun, Norbert A; Kohlenberg, Birgit; Sim, Sherina; Meier, Manfred; Hammerschmidt, Franz-Josef

    2009-09-01

    Jasminum flexile flower absolute from the south of India and the corresponding vacuum headspace (VHS) sample of the absolute were analyzed using GC and GC-MS. Three other commercially available Indian jasmine absolutes 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 absolute, with methyl linolate, benzyl salicylate, benzyl benzoate, (2E,6E)-farnesol, and benzyl acetate as the main constituents. A detailed olfactory evaluation was also performed. PMID:19831037

  10. Universal Cosmic Absolute and Modern Science

    NASA Astrophysics Data System (ADS)

    Kostro, Ludwik

    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 Absolute of Science and should be called, in my opinion, the Universal Cosmic Absolute of Modern Science. It will be also shown that the Universal Cosmic Absolute 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 Absolute will constitute in such a theory the radical all penetrating Ultimate Basic Reality and will substitute step by step the traditional supernatural personal Absolute.

  11. Refractive errors in children.

    PubMed

    Tongue, A C

    1987-12-01

    Optical correction of refractive errors in infants and young children is indicated when the refractive errors are sufficiently large to cause unilateral or bilateral amblyopia, if they are impairing the child's ability to function normally, or if the child has accommodative strabismus. Screening for refractive errors is important and should be performed as part of the annual physical examination in all verbal children. Screening for significant refractive errors in preverbal children is more difficult; however, the red reflex test of Bruckner is useful for the detection of anisometropic refractive errors. The photorefraction test, which is an adaptation of Bruckner's red reflex test, may prove to be a useful screening device for detecting bilateral as well as unilateral refractive errors. Objective testing as well as subjective testing enables ophthalmologists to prescribe proper optical correction for refractive errors for infants and children of any age. PMID:3317238

  12. Error-prone signalling.

    PubMed

    Johnstone, R A; Grafen, A

    1992-06-22

    The handicap principle of Zahavi is potentially of great importance to the study of biological communication. Existing models of the handicap principle, however, make the unrealistic assumption that communication is error free. It seems possible, therefore, that Zahavi's arguments do not apply to real signalling systems, in which some degree of error is inevitable. Here, we present a general evolutionarily stable strategy (ESS) model of the handicap principle which incorporates perceptual error. We show that, for a wide range of error functions, error-prone signalling systems must be honest at equilibrium. Perceptual error is thus unlikely to threaten the validity of the handicap principle. Our model represents a step towards greater realism, and also opens up new possibilities for biological signalling theory. Concurrent displays, direct perception of quality, and the evolution of 'amplifiers' and 'attenuators' are all probable features of real signalling systems, yet handicap models based on the assumption of error-free communication cannot accommodate these possibilities. PMID:1354361

  13. Morphology and Absolute Magnitudes of the SDSS DR7 QSOs

    NASA Astrophysics Data System (ADS)

    Coelho, B.; Andrei, A. H.; Antón, S.

    2014-10-01

    The ESA mission Gaia will furnish a complete census of the Milky Way, delivering astrometrics, dynamics, and astrophysics information for 1 billion stars. Operating in all-sky repeated survey mode, Gaia will also provide measurements of extra-galactic objects. Among the later there will be at least 500,000 QSOs that will be used to build the reference frame upon which the several independent observations will be combined and interpreted. Not all the QSOs are equally suited to fulfill this role of fundamental, fiducial grid-points. Brightness, morphology, and variability define the astrometric error budget for each object. We made use of 3 morphological parameters based on the PSF sharpness, circularity and gaussianity, which enable us to distinguish the "real point-like" QSOs. These parameters are being explored on the spectroscopically certified QSOs of the SDSS DR7, to compare the performance against other morphology classification schemes, as well as to derive properties of the host galaxy. We present a new method, based on the Gaia quasar database, to derive absolute magnitudes, on the SDSS filters domain. The method can be extrapolated all over the optical window, including the Gaia filters. We discuss colors derived from SDSS apparent magnitudes and colors based on absolute magnitudes that we obtained tanking into account corrections for dust extinction, either intergalactic or from the QSO host, and for the Lyman α forest. In the future we want to further discuss properties of the host galaxies, comparing for e.g. the obtained morphological classification with the color, the apparent and absolute magnitudes, and the redshift distributions.

  14. Absolute blood velocity measured with a modified fundus camera

    NASA Astrophysics Data System (ADS)

    Duncan, Donald D.; Lemaillet, Paul; Ibrahim, Mohamed; Nguyen, Quan Dong; Hiller, Matthias; Ramella-Roman, Jessica

    2010-09-01

    We present a new method for the quantitative estimation of blood flow velocity, based on the use of the Radon transform. The specific application is for measurement of blood flow velocity in the retina. Our modified fundus camera uses illumination from a green LED and captures imagery with a high-speed CCD camera. The basic theory is presented, and typical results are shown for an in vitro flow model using blood in a capillary tube. Subsequently, representative results are shown for representative fundus imagery. This approach provides absolute velocity and flow direction along the vessel centerline or any lateral displacement therefrom. We also provide an error analysis allowing estimation of confidence intervals for the estimated velocity.

  15. Measured and modelled absolute gravity changes in Greenland

    NASA Astrophysics Data System (ADS)

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

    2014-01-01

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

  16. Full field imaging based instantaneous hyperspectral absolute refractive index measurement

    SciTech Connect

    Baba, Justin S; Boudreaux, Philip R

    2012-01-01

    Multispectral refractometers typically measure refractive index (RI) at discrete monochromatic wavelengths via a serial process. We report on the demonstration of a white light full field imaging based refractometer capable of instantaneous multispectral measurement of absolute RI of clear liquid/gel samples across the entire visible light spectrum. The broad optical bandwidth refractometer is capable of hyperspectral measurement of RI in the range 1.30 1.70 between 400nm 700nm with a maximum error of 0.0036 units (0.24% of actual) at 414nm for a = 1.50 sample. We present system design and calibration method details as well as results from a system validation sample.

  17. Absolute isotopic abundances of TI in meteorites

    NASA Astrophysics Data System (ADS)

    Niederer, F. R.; Papanastassiou, D. A.; Wasserburg, G. J.

    1985-03-01

    The absolute isotope abundance of Ti has been determined in Ca-Al-rich inclusions from the Allende and Leoville meteorites and in samples of whole meteorites. The absolute Ti isotope abundances differ by a significant mass dependent isotope fractionation transformation from the previously reported abundances, which were normalized for fractionation using 46Ti/48Ti. Therefore, the absolute compositions define distinct nucleosynthetic components from those previously identified or reflect the existence of significant mass dependent isotope fractionation in nature. The authors provide a general formalism for determining the possible isotope compositions of the exotic Ti from the measured composition, for different values of isotope fractionation in nature and for different mixing ratios of the exotic and normal components.

  18. Molecular iodine absolute frequencies. Final report

    SciTech Connect

    Sansonetti, C.J.

    1990-06-25

    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 absolute frequency. In 3 cases, a nearby alternate line was selected for measurement because no well-resolved component was found for the specified line. Absolute 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 absolute measurement, the line classification, and a Doppler-free spectrum are given.

  19. 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 PMID:26478959

  20. Absolute calibration in vivo measurement systems

    SciTech Connect

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

    1991-02-01

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

  1. Closed-loop step motor control using absolute encoders

    SciTech Connect

    Hicks, J.S.; Wright, M.C.

    1997-08-01

    A multi-axis, step motor control system was developed to accurately position and control the operation of a triple axis spectrometer at the High Flux Isotope Reactor (HFIR) located at Oak Ridge National Laboratory. Triple axis spectrometers are used in neutron scattering and diffraction experiments and require highly accurate positioning. This motion control system can handle up to 16 axes of motion. Four of these axes are outfitted with 17-bit absolute encoders. These four axes are controlled with a software feedback loop that terminates the move based on real-time position information from the absolute encoders. Because the final position of the actuator is used to stop the motion of the step motors, the moves can be made accurately in spite of the large amount of mechanical backlash from a chain drive between the motors and the spectrometer arms. A modified trapezoidal profile, custom C software, and an industrial PC, were used to achieve a positioning accuracy of 0.00275 degrees of rotation. A form of active position maintenance ensures that the angles are maintained with zero error or drift.

  2. Stitching interferometry and absolute surface shape metrology: similarities

    NASA Astrophysics Data System (ADS)

    Bray, Michael

    2001-12-01

    Stitching interferometry is a method of analysing large optical components using a standard small interferometer. This result is obtained by taking multiple overlapping images of the large component, and numerically stitching these sub-apertures together by computing a correcting Tip- Tilt-Piston correction for each sub-aperture. All real-life measurement techniques require a calibration phase. By definition, a perfect surface does not exist. Methods abound for the accurate measurement of diameters (viz., the Three Flat Test). However, we need total surface knowledge of the reference surface, because the stitched overlap areas will suffer from the slightest deformation. One must not be induced into thinking that Stitching is the cause of this error: it simply highlights the lack of absolute knowledge of the reference surface, or the lack of adequate thermal control, issues which are often sidetracked... The goal of this paper is to highlight the above-mentioned calibration problems in interferometry in general, and in stitching interferometry in particular, and show how stitching hardware and software can be conveniently used to provide the required absolute surface shape metrology. Some measurement figures will illustrate this article.

  3. Aircraft system modeling error and control error

    NASA Technical Reports Server (NTRS)

    Kulkarni, Nilesh V. (Inventor); Kaneshige, John T. (Inventor); Krishnakumar, Kalmanje S. (Inventor); Burken, John J. (Inventor)

    2012-01-01

    A method for modeling error-driven adaptive control of an aircraft. Normal aircraft plant dynamics is modeled, using an original plant description in which a controller responds to a tracking error e(k) to drive the component to a normal reference value according to an asymptote curve. Where the system senses that (1) at least one aircraft plant component is experiencing an excursion and (2) the return of this component value toward its reference value is not proceeding according to the expected controller characteristics, neural network (NN) modeling of aircraft plant operation may be changed. However, if (1) is satisfied but the error component is returning toward its reference value according to expected controller characteristics, the NN will continue to model operation of the aircraft plant according to an original description.

  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. Precise Measurement of the Absolute Fluorescence Yield

    NASA Astrophysics Data System (ADS)

    Ave, M.; Bohacova, M.; Daumiller, K.; Di Carlo, P.; di Giulio, C.; San Luis, P. Facal; Gonzales, D.; Hojvat, C.; Hörandel, J. R.; Hrabovsky, M.; Iarlori, M.; Keilhauer, B.; Klages, H.; Kleifges, M.; Kuehn, F.; Monasor, M.; Nozka, L.; Palatka, M.; Petrera, S.; Privitera, P.; Ridky, J.; Rizi, V.; D'Orfeuil, B. Rouille; Salamida, F.; Schovanek, P.; Smida, R.; Spinka, H.; Ulrich, A.; Verzi, V.; Williams, C.

    2011-09-01

    We present preliminary results of the absolute yield of fluorescence emission in atmospheric gases. Measurements were performed at the Fermilab Test Beam Facility with a variety of beam particles and gases. Absolute calibration of the fluorescence yield to 5% level was achieved by comparison with two known light sources--the Cherenkov light emitted by the beam particles, and a calibrated nitrogen laser. The uncertainty of the energy scale of current Ultra-High Energy Cosmic Rays experiments will be significantly improved by the AIRFLY measurement.

  6. Absolutely relative or relatively absolute: violations of value invariance in human decision making.

    PubMed

    Teodorescu, Andrei R; Moran, Rani; Usher, Marius

    2016-02-01

    Making decisions based on relative rather than absolute information processing is tied to choice optimality via the accumulation of evidence differences and to canonical neural processing via accumulation of evidence ratios. These theoretical frameworks predict invariance of decision latencies to absolute intensities that maintain differences and ratios, respectively. While information about the absolute values of the choice alternatives is not necessary for choosing the best alternative, it may nevertheless hold valuable information about the context of the decision. To test the sensitivity of human decision making to absolute values, we manipulated the intensities of brightness stimuli pairs while preserving either their differences or their ratios. Although asked to choose the brighter alternative relative to the other, participants responded faster to higher absolute values. Thus, our results provide empirical evidence for human sensitivity to task irrelevant absolute values indicating a hard-wired mechanism that precedes executive control. Computational investigations of several modelling architectures reveal two alternative accounts for this phenomenon, which combine absolute and relative processing. One account involves accumulation of differences with activation dependent processing noise and the other emerges from accumulation of absolute values subject to the temporal dynamics of lateral inhibition. The potential adaptive role of such choice mechanisms is discussed. PMID:26022836

  7. Two-stage model of African absolute motion during the last 30 million years

    NASA Astrophysics Data System (ADS)

    Pollitz, Fred F.

    1991-07-01

    The absolute motion of Africa (relative to the hotspots) for the past 30 My is modeled with two Euler vectors, with a change occurring at 6 Ma. Because of the high sensitivity of African absolute motions to errors in the absolute motions of the North America and Pacific plates, both the pre-6 Ma and post-6 Ma African absolute motions are determined simultaneously with North America and Pacific absolute motions for various epochs. Geologic data from the northern Atlantic and hotspot tracks from the African plate are used to augment previous data sets for the North America and Pacific plates. The difference between the pre-6 Ma and post-6 Ma absolute plate motions may be represented as a counterclockwise rotation about a pole at 48 °S, 84 °E, with angular velocity 0.085 °/My. This change is supported by geologic evidence along a large portion of the African plate boundary, including the Red Sea and Gulf of Aden spreading systems, the Alpine deformation zone, and the central and southern mid-Atlantic Ridge. Although the change is modeled as one abrupt transition at 6 Ma, it was most likely a gradual change spanning the period 8-4 Ma. As a likely mechanism for the change, we favor strong asthenospheric return flow from the Afar hotspot towards the southwest; this could produce the uniform southwesterly shift in absolute motion which we have inferred as well as provide a mechanism for the opening of the East African Rift. Comparing the absolute motions of the North America and Pacific plates with earlier estimates, the pole positions are revised by up to 5° and the angular velocities are decreased by 10-20%.

  8. Error detection method

    DOEpatents

    Olson, Eric J.

    2013-06-11

    An apparatus, program product, and method that run an algorithm on a hardware based processor, generate a hardware error as a result of running the algorithm, generate an algorithm output for the algorithm, compare the algorithm output to another output for the algorithm, and detect the hardware error from the comparison. The algorithm is designed to cause the hardware based processor to heat to a degree that increases the likelihood of hardware errors to manifest, and the hardware error is observable in the algorithm output. As such, electronic components may be sufficiently heated and/or sufficiently stressed to create better conditions for generating hardware errors, and the output of the algorithm may be compared at the end of the run to detect a hardware error that occurred anywhere during the run that may otherwise not be detected by traditional methodologies (e.g., due to cooling, insufficient heat and/or stress, etc.).

  9. The Error in Total Error Reduction

    PubMed Central

    Witnauer, James E.; Urcelay, Gonzalo P.; Miller, Ralph R.

    2013-01-01

    Most models of human and animal learning assume that learning is proportional to the discrepancy between a delivered outcome and the outcome predicted by all cues present during that trial (i.e., total error across a stimulus compound). This total error reduction (TER) view has been implemented in connectionist and artificial neural network models to describe the conditions under which weights between units change. Electrophysiological work has revealed that the activity of dopamine neurons is correlated with the total error signal in models of reward learning. Similar neural mechanisms presumably support fear conditioning, human contingency learning, and other types of learning. Using a computational modelling approach, we compared several TER models of associative learning to an alternative model that rejects the TER assumption in favor of local error reduction (LER), which assumes that learning about each cue is proportional to the discrepancy between the delivered outcome and the outcome predicted by that specific cue on that trial. The LER model provided a better fit to the reviewed data than the TER models. Given the superiority of the LER model with the present data sets, acceptance of TER should be tempered. PMID:23891930

  10. Absolute partial photoionization cross sections of ozone.

    SciTech Connect

    Berkowitz, J.; Chemistry

    2008-04-01

    Despite the current concerns about ozone, absolute 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.

  11. Solving Absolute Value Equations Algebraically and Geometrically

    ERIC Educational Resources Information Center

    Shiyuan, Wei

    2005-01-01

    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 absolute value equation presented, for an interesting way to form an overall understanding of the concept.

  12. Teaching Absolute Value Inequalities to Mature Students

    ERIC Educational Resources Information Center

    Sierpinska, Anna; Bobos, Georgeana; Pruncut, Andreea

    2011-01-01

    This paper gives an account of a teaching experiment on absolute 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…

  13. Increasing Capacity: Practice Effects in Absolute Identification

    ERIC Educational Resources Information Center

    Dodds, Pennie; Donkin, Christopher; Brown, Scott D.; Heathcote, Andrew

    2011-01-01

    In most of the long history of the study of absolute 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…

  14. On Relative and Absolute Conviction in Mathematics

    ERIC Educational Resources Information Center

    Weber, Keith; Mejia-Ramos, Juan Pablo

    2015-01-01

    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 absolute 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…

  15. Absolute Points for Multiple Assignment Problems

    ERIC Educational Resources Information Center

    Adlakha, V.; Kowalski, K.

    2006-01-01

    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 absolute points to identify cells that must be loaded in any optimal solution. Unlike other methods, the first solution is the optimal solution. The…

  16. Nonequilibrium equalities in absolutely irreversible processes

    NASA Astrophysics Data System (ADS)

    Murashita, Yuto; Funo, Ken; Ueda, Masahito

    2015-03-01

    Nonequilibrium equalities have attracted considerable attention in the context of statistical mechanics and information thermodynamics. Integral nonequilibrium equalities reveal an ensemble property of the entropy production σ as = 1 . Although nonequilibrium equalities apply to rather general nonequilibrium situations, they break down in absolutely irreversible processes, where the forward-path probability vanishes and the entropy production diverges. We identify the mathematical origins of this inapplicability as the singularity of probability measure. As a result, we generalize conventional integral nonequilibrium equalities to absolutely irreversible processes as = 1 -λS , where λS is the probability of the singular part defined based on Lebesgue's decomposition theorem. The acquired equality contains two physical quantities related to irreversibility: σ characterizing ordinary irreversibility and λS describing absolute irreversibility. An inequality derived from the obtained equality demonstrates the absolute irreversibility leads to the fundamental lower bound on the entropy production. We demonstrate the validity of the obtained equality for a simple model.

  17. 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…

  18. Precision absolute positional measurement of laser beams.

    PubMed

    Fitzsimons, Ewan D; Bogenstahl, Johanna; Hough, James; Killow, Christian J; Perreur-Lloyd, Michael; Robertson, David I; Ward, Henry

    2013-04-20

    We describe an instrument which, coupled with a suitable coordinate measuring machine, facilitates the absolute measurement within the machine frame of the propagation direction of a millimeter-scale laser beam to an accuracy of around ±4 μm in position and ±20 μrad in angle. PMID:23669658

  19. Error coding simulations

    NASA Technical Reports Server (NTRS)

    Noble, Viveca K.

    1993-01-01

    There are various elements such as radio frequency interference (RFI) which may induce errors in data being transmitted via a satellite communication link. When a transmission is affected by interference or other error-causing elements, the transmitted data becomes indecipherable. It becomes necessary to implement techniques to recover from these disturbances. The objective of this research is to develop software which simulates error control circuits and evaluate the performance of these modules in various bit error rate environments. The results of the evaluation provide the engineer with information which helps determine the optimal error control scheme. The Consultative Committee for Space Data Systems (CCSDS) recommends the use of Reed-Solomon (RS) and convolutional encoders and Viterbi and RS decoders for error correction. The use of forward error correction techniques greatly reduces the received signal to noise needed for a certain desired bit error rate. The use of concatenated coding, e.g. inner convolutional code and outer RS code, provides even greater coding gain. The 16-bit cyclic redundancy check (CRC) code is recommended by CCSDS for error detection.

  20. Model Error Budgets

    NASA Technical Reports Server (NTRS)

    Briggs, Hugh C.

    2008-01-01

    An error budget is a commonly used tool in design of complex aerospace systems. It represents system performance requirements in terms of allowable errors and flows these down through a hierarchical structure to lower assemblies and components. The requirements may simply be 'allocated' based upon heuristics or experience, or they may be designed through use of physics-based models. This paper presents a basis for developing an error budget for models of the system, as opposed to the system itself. The need for model error budgets arises when system models are a principle design agent as is increasingly more common for poorly testable high performance space systems.

  1. Error coding simulations

    NASA Astrophysics Data System (ADS)

    Noble, Viveca K.

    1993-11-01

    There are various elements such as radio frequency interference (RFI) which may induce errors in data being transmitted via a satellite communication link. When a transmission is affected by interference or other error-causing elements, the transmitted data becomes indecipherable. It becomes necessary to implement techniques to recover from these disturbances. The objective of this research is to develop software which simulates error control circuits and evaluate the performance of these modules in various bit error rate environments. The results of the evaluation provide the engineer with information which helps determine the optimal error control scheme. The Consultative Committee for Space Data Systems (CCSDS) recommends the use of Reed-Solomon (RS) and convolutional encoders and Viterbi and RS decoders for error correction. The use of forward error correction techniques greatly reduces the received signal to noise needed for a certain desired bit error rate. The use of concatenated coding, e.g. inner convolutional code and outer RS code, provides even greater coding gain. The 16-bit cyclic redundancy check (CRC) code is recommended by CCSDS for error detection.

  2. Multiple acquisitions via sequential transfer of orphan spin polarization (MAeSTOSO): How far can we push residual spin polarization in solid-state NMR?

    PubMed

    Gopinath, T; Veglia, Gianluigi

    2016-06-01

    Conventional multidimensional magic angle spinning (MAS) solid-state NMR (ssNMR) experiments detect the signal arising from the decay of a single coherence transfer pathway (FID), resulting in one spectrum per acquisition time. Recently, we introduced two new strategies, namely DUMAS (DUal acquisition Magic Angle Spinning) and MEIOSIS (Multiple ExperIments via Orphan SpIn operatorS), that enable the simultaneous acquisitions of multidimensional ssNMR experiments using multiple coherence transfer pathways. Here, we combined the main elements of DUMAS and MEIOSIS to harness both orphan spin operators and residual polarization and increase the number of simultaneous acquisitions. We show that it is possible to acquire up to eight two-dimensional experiments using four acquisition periods per each scan. This new suite of pulse sequences, called MAeSTOSO for Multiple Acquisitions via Sequential Transfer of Orphan Spin pOlarization, relies on residual polarization of both (13)C and (15)N pathways and combines low- and high-sensitivity experiments into a single pulse sequence using one receiver and commercial ssNMR probes. The acquisition of multiple experiments does not affect the sensitivity of the main experiment; rather it recovers the lost coherences that are discarded, resulting in a significant gain in experimental time. Both merits and limitations of this approach are discussed. PMID:27039168

  3. New data on Mustelidae (Carnivora) from Southeast Asia: Siamogale thailandica, a peculiar otter-like mustelid from the late middle Miocene Mae Moh Basin, northern Thailand

    NASA Astrophysics Data System (ADS)

    Grohé, Camille; Chaimanee, Yaowalak; de Bonis, Louis; Yamee, Chotima; Blondel, Cécile; Jaeger, Jean-Jacques

    2010-11-01

    We report new dental remains of Mustelidae from the late middle Miocene of Mae Moh Basin, northern Thailand, improving the poor fossil record of the family in Southeast Asia. Siamogale thailandica is a poorly known mustelid, previously recorded from just a single tooth. Here we present over a hundred new specimens attributable to this species. S. thailandica shows a combination of primitive and convergent features of the dentition that makes its original subfamilial assignment to Lutrinae doubtful. Evidence from the dental morphology suggests that it belongs to a bunodont otter-like mustelid that evolved in convergence with “true” otters (Lutrinae) toward a semi-aquatic way of life. Autapomorphic features such as the height and the position of the m1 metaconid and the shape of the P4 lingual shelf make S. thailandica unique among Mustelidae. The morphology of this species is mostly similar to Mionictis species and Lartetictis dubia, reported in the Miocene of North America and Europe, respectively. These similarities could imply immigration events to Thailand in the early or middle Miocene. Alternately, the lineage leading to Siamogale might have deeper origins from an endemic early Miocene Southeast Asian mustelid.

  4. Multiple acquisitions via sequential transfer of orphan spin polarization (MAeSTOSO): How far can we push residual spin polarization in solid-state NMR?

    NASA Astrophysics Data System (ADS)

    Gopinath, T.; Veglia, Gianluigi

    2016-06-01

    Conventional multidimensional magic angle spinning (MAS) solid-state NMR (ssNMR) experiments detect the signal arising from the decay of a single coherence transfer pathway (FID), resulting in one spectrum per acquisition time. Recently, we introduced two new strategies, namely DUMAS (DUal acquisition Magic Angle Spinning) and MEIOSIS (Multiple ExperIments via Orphan SpIn operatorS), that enable the simultaneous acquisitions of multidimensional ssNMR experiments using multiple coherence transfer pathways. Here, we combined the main elements of DUMAS and MEIOSIS to harness both orphan spin operators and residual polarization and increase the number of simultaneous acquisitions. We show that it is possible to acquire up to eight two-dimensional experiments using four acquisition periods per each scan. This new suite of pulse sequences, called MAeSTOSO for Multiple Acquisitions via Sequential Transfer of Orphan Spin pOlarization, relies on residual polarization of both 13C and 15N pathways and combines low- and high-sensitivity experiments into a single pulse sequence using one receiver and commercial ssNMR probes. The acquisition of multiple experiments does not affect the sensitivity of the main experiment; rather it recovers the lost coherences that are discarded, resulting in a significant gain in experimental time. Both merits and limitations of this approach are discussed.

  5. Absolute phase retrieval for defocused fringe projection three-dimensional measurement

    NASA Astrophysics Data System (ADS)

    Zheng, Dongliang; Da, Feipeng

    2014-02-01

    Defocused fringe projection three-dimensional technique based on pulse-width modulation (PWM) can generate high-quality sinusoidal fringe patterns. It only uses slightly defocused binary structured patterns which can eliminate the gamma problem (i.e. nonlinear response), and the phase error can be significantly reduced. However, when the projector is defocused, it is difficult to retrieve the absolute phase from the wrapped phase. A recently proposed phase coding method is efficient for absolute phase retrieval, but the gamma problem leads this method not so reliable. In this paper, we use the PWM technique to generate fringe patterns for the phase coding method. The gamma problem of the projector can be eliminated, and correct absolute phase can be retrieved. The proposed method only uses two grayscale values (0's and 255's), which can be used for real-time 3D shape measurement. Both simulation and experiment demonstrate the performance of the proposed method.

  6. The correction of vibration in frequency scanning interferometry based absolute distance measurement system for dynamic measurements

    NASA Astrophysics Data System (ADS)

    Lu, Cheng; Liu, Guodong; Liu, Bingguo; Chen, Fengdong; Zhuang, Zhitao; Xu, Xinke; Gan, Yu

    2015-10-01

    Absolute distance measurement systems are of significant interest in the field of metrology, which could improve the manufacturing efficiency and accuracy 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 absolute 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 absolute 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 times 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.

  7. Absolute Cavity Pyrgeometer to Measure the Absolute Outdoor Longwave Irradiance with Traceability to International System of Units, SI

    SciTech Connect

    Reda, I.; Zeng, J.; Scheuch, J.; Hanssen, L.; Wilthan, B.; Myers, D.; Stoffel, T.

    2012-03-01

    This article describes a method of measuring the absolute outdoor longwave irradiance using an absolute cavity pyrgeometer (ACP), U.S. Patent application no. 13/049, 275. The ACP consists of domeless thermopile pyrgeometer, gold-plated concentrator, temperature controller, and data acquisition. The dome was removed from the pyrgeometer to remove errors associated with dome transmittance and the dome correction factor. To avoid thermal convection and wind effect errors resulting from using a domeless thermopile, the gold-plated concentrator was placed above the thermopile. The concentrator is a dual compound parabolic concentrator (CPC) with 180{sup o} view angle to measure the outdoor incoming longwave irradiance from the atmosphere. The incoming irradiance is reflected from the specular gold surface of the CPC and concentrated on the 11 mm diameter of the pyrgeometer's blackened thermopile. The CPC's interior surface design and the resulting cavitation result in a throughput value that was characterized by the National Institute of Standards and Technology. The ACP was installed horizontally outdoor on an aluminum plate connected to the temperature controller to control the pyrgeometer's case temperature. The responsivity of the pyrgeometer's thermopile detector was determined by lowering the case temperature and calculating the rate of change of the thermopile output voltage versus the changing net irradiance. The responsivity is then used to calculate the absolute atmospheric longwave irradiance with an uncertainty estimate (U{sub 95}) of {+-}3.96 W m{sup 02} with traceability to the International System of Units, SI. The measured irradiance was compared with the irradiance measured by two pyrgeometers calibrated by the World Radiation Center with traceability to the Interim World Infrared Standard Group, WISG. A total of 408 readings were collected over three different nights. The calculated irradiance measured by the ACP was 1.5 W/m{sup 2} lower than that

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

    NASA Astrophysics Data System (ADS)

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

    2012-03-01

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

  9. Everyday Scale Errors

    ERIC Educational Resources Information Center

    Ware, Elizabeth A.; Uttal, David H.; DeLoache, Judy S.

    2010-01-01

    Young children occasionally make "scale errors"--they attempt to fit their bodies into extremely small objects or attempt to fit a larger object into another, tiny, object. For example, a child might try to sit in a dollhouse-sized chair or try to stuff a large doll into it. Scale error research was originally motivated by parents' and…

  10. Medical error and disclosure.

    PubMed

    White, Andrew A; Gallagher, Thomas H

    2013-01-01

    Errors occur commonly in healthcare and can cause significant harm to patients. Most errors arise from a combination of individual, system, and communication failures. Neurologists may be involved in harmful errors in any practice setting and should familiarize themselves with tools to prevent, report, and examine errors. Although physicians, patients, and ethicists endorse candid disclosure of harmful medical errors to patients, many physicians express uncertainty about how to approach these conversations. A growing body of research indicates physicians often fail to meet patient expectations for timely and open disclosure. Patients desire information about the error, an apology, and a plan for preventing recurrence of the error. To meet these expectations, physicians should participate in event investigations and plan thoroughly for each disclosure conversation, preferably with a disclosure coach. Physicians should also anticipate and attend to the ongoing medical and emotional needs of the patient. A cultural change towards greater transparency following medical errors is in motion. Substantial progress is still required, but neurologists can further this movement by promoting policies and environments conducive to open reporting, respectful disclosure to patients, and support for the healthcare workers involved. PMID:24182370

  11. Absolute testing of flats in sub-stitching interferometer by rotation-shift method

    NASA Astrophysics Data System (ADS)

    Jia, Xin; Xu, Fuchao; Xie, Weimin; Li, Yun; Xing, Tingwen

    2015-09-01

    Most of the commercial available sub-aperture stitching interferometers measure the surface with a standard lens that produces a reference wavefront, and the precision of the interferometer is generally limited by the standard lens. The test accuracy can be achieved by removing the error of reference surface by the absolute testing method. When the testing accuracy (repeatability and reproducibility) is close to 1nm, in addition to the reference surface, other factors will also affect the measuring accuracy such as environment, zoom magnification, stitching precision, tooling and fixture, the characteristics of optical materials and so on. We establish a stitching system in the thousand level cleanroom. The stitching system is including the Zygo interferometer, the motion system with Bilz active isolation system at level VC-F. We review the traditional absolute flat testing methods and emphasize the method of rotation-shift functions. According to the rotation-shift method we get the profile of the reference lens and the testing lens. The problem of the rotation-shift method is the tilt error. In the motion system, we control the tilt error no more than 4 second to reduce the error. In order to obtain higher testing accuracy, we analyze the influence surface shape measurement accuracy by recording the environment error with the fluke testing equipment.

  12. A binary spelling interface with random errors.

    PubMed

    Perelmouter, J; Birbaumer, N

    2000-06-01

    An algorithm for design of a spelling interface based on a modified Huffman's algorithm is presented. This algorithm builds a full binary tree that allows to maximize an average probability to reach a leaf where a required character is located when a choice at each node is made with possible errors. A means to correct errors (a delete-function) and an optimization method to build this delete-function into the binary tree are also discussed. Such a spelling interface could be successfully applied to any menu-orientated alternative communication system when a user (typically, a patient with devastating neuromuscular handicap) is not able to express an intended single binary response, either through motor responses or by using of brain-computer interfaces, with an absolute reliability. PMID:10896195

  13. Absolute and relative dosimetry for ELIMED

    SciTech Connect

    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.

    2013-07-26

    The definition of detectors, methods and procedures for the absolute 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 absolute dose measure at the end of the transport beamline with an accuracy 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.

  14. Probing absolute spin polarization at the nanoscale.

    PubMed

    Eltschka, Matthias; Jäck, Berthold; Assig, Maximilian; Kondrashov, Oleg V; Skvortsov, Mikhail A; Etzkorn, Markus; Ast, Christian R; Kern, Klaus

    2014-12-10

    Probing absolute 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 absolute 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

  15. Absolute-magnitude distributions of supernovae

    SciTech Connect

    Richardson, Dean; Wright, John; Jenkins III, Robert L.; Maddox, Larry

    2014-05-01

    The absolute-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 absolute blue magnitude of –19.25. The IIP distribution was the dimmest at –16.75.

  16. Absolute radiometry and the solar constant

    NASA Technical Reports Server (NTRS)

    Willson, R. C.

    1974-01-01

    A series of active cavity radiometers (ACRs) are described which have been developed as standard detectors for the accurate measurement of irradiance in absolute 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 absolute 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).

  17. Asteroid absolute magnitudes and slope parameters

    NASA Technical Reports Server (NTRS)

    Tedesco, Edward F.

    1991-01-01

    A new listing of absolute 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 absolute magnitudes and slope parameters will be used to deduce the most reliable bias-corrected asteroid size-frequency distribution yet made.

  18. Absolute calibration of TFTR helium proportional counters

    SciTech Connect

    Strachan, J.D.; Diesso, M.; Jassby, D.; Johnson, L.; McCauley, S.; Munsat, T.; Roquemore, A.L.; Barnes, C.W. |; Loughlin, M. |

    1995-06-01

    The TFTR helium proportional counters are located in the central five (5) channels of the TFTR multichannel neutron collimator. These detectors were absolutely calibrated using a 14 MeV neutron generator positioned at the horizontal midplane of the TFTR vacuum vessel. The neutron generator position was scanned in centimeter steps to determine the collimator aperture width to 14 MeV neutrons and the absolute sensitivity of each channel. Neutron profiles were measured for TFTR plasmas with time resolution between 5 msec and 50 msec depending upon count rates. The He detectors were used to measure the burnup of 1 MeV tritons in deuterium plasmas, the transport of tritium in trace tritium experiments, and the residual tritium levels in plasmas following 50:50 DT experiments.

  19. Absolute enantioselective separation: optical activity ex machina.

    PubMed

    Bielski, Roman; Tencer, Michal

    2005-11-01

    The paper describes methodology of using three independent macroscopic factors affecting molecular orientation to accomplish separation of a racemic mixture without the presence of any other chiral compounds, i. e., absolute enantioselective separation (AES) which is an extension of a concept of applying these factors to absolute asymmetric synthesis. The three factors may be applied simultaneously or, if their effects can be retained, consecutively. The resulting three mutually orthogonal or near orthogonal directors constitute a true chiral influence and their scalar triple product is the measure of the chirality of the system. AES can be executed in a chromatography-like microfluidic process in the presence of an electric field. It may be carried out on a chemically modified flat surface, a monolithic polymer column made of a mesoporous material, each having imparted directional properties. Separation parameters were estimated for these media and possible implications for the natural homochirality are discussed. PMID:16342798

  20. An absolute measure for a key currency

    NASA Astrophysics Data System (ADS)

    Oya, Shunsuke; Aihara, Kazuyuki; Hirata, Yoshito

    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 absolute general measure for a key currency. Here, we investigate the 24-hour periodicity of foreign exchange markets using a recurrence plot, and define an absolute measure for a key currency based on the strength of the periodicity. Moreover, we analyze the time 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.

  1. From Hubble's NGSL to Absolute Fluxes

    NASA Technical Reports Server (NTRS)

    Heap, Sara R.; Lindler, Don

    2012-01-01

    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 absolute flux standards at ground-based observatories. However, the uncertainty in the absolute 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.

  2. Metallic Magnetic Calorimeters for Absolute Activity Measurement

    NASA Astrophysics Data System (ADS)

    Loidl, M.; Leblanc, E.; Rodrigues, M.; Bouchard, J.; Censier, B.; Branger, T.; Lacour, D.

    2008-05-01

    We present a prototype of metallic magnetic calorimeters that we are developing for absolute activity measurements of low energy emitting radionuclides. We give a detailed description of the realization of the prototype, containing an 55Fe source inside the detector absorber. We present the analysis of first data taken with this detector and compare the result of activity measurement with liquid scintillation counting. We also propose some ways for reducing the uncertainty on the activity determination with this new technique.

  3. Absolute photoionization cross sections of atomic oxygen

    NASA Technical Reports Server (NTRS)

    Samson, J. A. R.; Pareek, P. N.

    1985-01-01

    The absolute 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.

  4. Absolute photoionization cross sections of atomic oxygen

    NASA Technical Reports Server (NTRS)

    Samson, J. A. R.; Pareek, P. N.

    1982-01-01

    The absolute 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.

  5. Silicon Absolute X-Ray Detectors

    SciTech Connect

    Seely, John F.; Korde, Raj; Sprunck, Jacob; Medjoubi, Kadda; Hustache, Stephanie

    2010-06-23

    The responsivity of silicon photodiodes having no loss in the entrance window, measured using synchrotron radiation in the 1.75 to 60 keV range, was compared to the responsivity calculated using the silicon thickness measured using near-infrared light. The measured and calculated responsivities agree with an average difference of 1.3%. This enables their use as absolute x-ray detectors.

  6. Blood pressure targets and absolute cardiovascular risk.

    PubMed

    Odutayo, Ayodele; Rahimi, Kazem; Hsiao, Allan J; Emdin, Connor A

    2015-08-01

    In the Eighth Joint National Committee guideline on hypertension, the threshold for the initiation of blood pressure-lowering treatment for elderly adults (≥60 years) without chronic kidney disease or diabetes mellitus was raised from 140/90 mm Hg to 150/90 mm Hg. However, the committee was not unanimous in this decision, particularly because a large proportion of adults ≥60 years may be at high cardiovascular risk. On the basis of Eighth Joint National Committee guideline, we sought to determine the absolute 10-year risk of cardiovascular disease among these adults through analyzing the National Health and Nutrition Examination Survey (2005-2012). The primary outcome measure was the proportion of adults who were at ≥20% predicted absolute cardiovascular risk and above goals for the Seventh Joint National Committee guideline but reclassified as at target under the Eighth Joint National Committee guideline (reclassified). The Framingham General Cardiovascular Disease Risk Score was used. From 2005 to 2012, the surveys included 12 963 adults aged 30 to 74 years with blood pressure measurements, of which 914 were reclassified based on the guideline. Among individuals reclassified as not in need of additional treatment, the proportion of adults 60 to 74 years without chronic kidney disease or diabetes mellitus at ≥20% absolute risk was 44.8%. This corresponds to 0.8 million adults. The proportion at high cardiovascular risk remained sizable among adults who were not receiving blood pressure-lowering treatment. Taken together, a sizable proportion of reclassified adults 60 to 74 years without chronic kidney disease or diabetes mellitus was at ≥20% absolute cardiovascular risk. PMID:26056340

  7. Absolute distance measurements by variable wavelength interferometry

    NASA Astrophysics Data System (ADS)

    Bien, F.; Camac, M.; Caulfield, H. J.; Ezekiel, S.

    1981-02-01

    This paper describes a laser interferometer which provides absolute distance measurements using tunable lasers. An active feedback loop system, in which the laser frequency is locked to the optical path length difference of the interferometer, is used to tune the laser wavelengths. If the two wavelengths are very close, electronic frequency counters can be used to measure the beat frequency between the two laser frequencies and thus to determine the optical path difference between the two legs of the interferometer.

  8. Uncorrected refractive errors

    PubMed Central

    Naidoo, Kovin S; Jaggernath, Jyoti

    2012-01-01

    Global estimates indicate that more than 2.3 billion people in the world suffer from poor vision due to refractive error; of which 670 million people are considered visually impaired because they do not have access to corrective treatment. Refractive errors, if uncorrected, results in an impaired quality of life for millions of people worldwide, irrespective of their age, sex and ethnicity. Over the past decade, a series of studies using a survey methodology, referred to as Refractive Error Study in Children (RESC), were performed in populations with different ethnic origins and cultural settings. These studies confirmed that the prevalence of uncorrected refractive errors is considerably high for children in low-and-middle-income countries. Furthermore, uncorrected refractive error has been noted to have extensive social and economic impacts, such as limiting educational and employment opportunities of economically active persons, healthy individuals and communities. The key public health challenges presented by uncorrected refractive errors, the leading cause of vision impairment across the world, require urgent attention. To address these issues, it is critical to focus on the development of human resources and sustainable methods of service delivery. This paper discusses three core pillars to addressing the challenges posed by uncorrected refractive errors: Human Resource (HR) Development, Service Development and Social Entrepreneurship. PMID:22944755

  9. Uncorrected refractive errors.

    PubMed

    Naidoo, Kovin S; Jaggernath, Jyoti

    2012-01-01

    Global estimates indicate that more than 2.3 billion people in the world suffer from poor vision due to refractive error; of which 670 million people are considered visually impaired because they do not have access to corrective treatment. Refractive errors, if uncorrected, results in an impaired quality of life for millions of people worldwide, irrespective of their age, sex and ethnicity. Over the past decade, a series of studies using a survey methodology, referred to as Refractive Error Study in Children (RESC), were performed in populations with different ethnic origins and cultural settings. These studies confirmed that the prevalence of uncorrected refractive errors is considerably high for children in low-and-middle-income countries. Furthermore, uncorrected refractive error has been noted to have extensive social and economic impacts, such as limiting educational and employment opportunities of economically active persons, healthy individuals and communities. The key public health challenges presented by uncorrected refractive errors, the leading cause of vision impairment across the world, require urgent attention. To address these issues, it is critical to focus on the development of human resources and sustainable methods of service delivery. This paper discusses three core pillars to addressing the challenges posed by uncorrected refractive errors: Human Resource (HR) Development, Service Development and Social Entrepreneurship. PMID:22944755

  10. Absolute dosimetry for extreme-ultraviolet lithography

    NASA Astrophysics Data System (ADS)

    Berger, Kurt W.; Campiotti, Richard H.

    2000-06-01

    The accurate measurement of an exposure dose reaching the wafer on an extreme ultraviolet (EUV) lithographic system has been a technical challenge directly applicable to the evaluation of candidate EUV resist materials and calculating lithography system throughputs. We have developed a dose monitoring sensor system that can directly measure EUV intensities at the wafer plane of a prototype EUV lithographic system. This sensor system, located on the wafer stage adjacent to the electrostatic chuck used to grip wafers, operates by translating the sensor into the aerial image, typically illuminating an 'open' (unpatterned) area on the reticle. The absolute signal strength can be related to energy density at the wafer, and thus used to determine resist sensitivity, and the signal as a function of position can be used to determine illumination uniformity at the wafer plane. Spectral filtering to enhance the detection of 13.4 nm radiation was incorporated into the sensor. Other critical design parameters include the packaging and amplification technologies required to place this device into the space and vacuum constraints of a EUV lithography environment. We describe two approaches used to determine the absolute calibration of this sensor. The first conventional approach requires separate characterization of each element of the sensor. A second novel approach uses x-ray emission from a mildly radioactive iron source to calibrate the absolute response of the entire sensor system (detector and electronics) in a single measurement.

  11. Insulin use: preventable errors.

    PubMed

    2014-01-01

    Insulin is vital for patients with type 1 diabetes and useful for certain patients with type 2 diabetes. The serious consequences of insulin-related medication errors are overdose, resulting in severe hypoglycaemia, causing seizures, coma and even death; or underdose, resulting in hyperglycaemia and sometimes ketoacidosis. Errors associated with the preparation and administration of insulin are often reported, both outside and inside the hospital setting. These errors are preventable. By analysing reports from organisations devoted to medication error prevention and from poison control centres, as well as a few studies and detailed case reports of medication errors, various types of error associated with insulin use have been identified, especially in the hospital setting. Generally, patients know more about the practicalities of their insulin treatment than healthcare professionals with intermittent involvement. Medication errors involving insulin can occur at each step of the medication-use process: prescribing, data entry, preparation, dispensing and administration. When prescribing insulin, wrong-dose errors have been caused by the use of abbreviations, especially "U" instead of the word "units" (often resulting in a 10-fold overdose because the "U" is read as a zero), or by failing to write the drug's name correctly or in full. In electronic prescribing, the sheer number of insulin products is a source of confusion and, ultimately, wrong-dose errors, and often overdose. Prescribing, dispensing or administration software is rarely compatible with insulin prescriptions in which the dose is adjusted on the basis of the patient's subsequent capillary blood glucose readings, and can therefore generate errors. When preparing and dispensing insulin, a tuberculin syringe is sometimes used instead of an insulin syringe, leading to overdose. Other errors arise from confusion created by similar packaging, between different insulin products or between insulin and other

  12. Error Prevention Aid

    NASA Technical Reports Server (NTRS)

    1987-01-01

    In a complex computer environment there is ample opportunity for error, a mistake by a programmer, or a software-induced undesirable side effect. In insurance, errors can cost a company heavily, so protection against inadvertent change is a must for the efficient firm. The data processing center at Transport Life Insurance Company has taken a step to guard against accidental changes by adopting a software package called EQNINT (Equations Interpreter Program). EQNINT cross checks the basic formulas in a program against the formulas that make up the major production system. EQNINT assures that formulas are coded correctly and helps catch errors before they affect the customer service or its profitability.

  13. Facts about Refractive Errors

    MedlinePlus

    ... the lens can cause refractive errors. What is refraction? Refraction is the bending of light as it passes ... rays entering the eye, causing a more precise refraction or focus. In many cases, contact lenses provide ...

  14. Errors in prenatal diagnosis.

    PubMed

    Anumba, Dilly O C

    2013-08-01

    Prenatal screening and diagnosis are integral to antenatal care worldwide. Prospective parents are offered screening for common fetal chromosomal and structural congenital malformations. In most developed countries, prenatal screening is routinely offered in a package that includes ultrasound scan of the fetus and the assay in maternal blood of biochemical markers of aneuploidy. Mistakes can arise at any point of the care pathway for fetal screening and diagnosis, and may involve individual or corporate systemic or latent errors. Special clinical circumstances, such as maternal size, fetal position, and multiple pregnancy, contribute to the complexities of prenatal diagnosis and to the chance of error. Clinical interventions may lead to adverse outcomes not caused by operator error. In this review I discuss the scope of the errors in prenatal diagnosis, and highlight strategies for their prevention and diagnosis, as well as identify areas for further research and study to enhance patient safety. PMID:23725900

  15. Error mode prediction.

    PubMed

    Hollnagel, E; Kaarstad, M; Lee, H C

    1999-11-01

    The study of accidents ('human errors') has been dominated by efforts to develop 'error' taxonomies and 'error' models that enable the retrospective identification of likely causes. In the field of Human Reliability Analysis (HRA) there is, however, a significant practical need for methods that can predict the occurrence of erroneous actions--qualitatively and quantitatively. The present experiment tested an approach for qualitative performance prediction based on the Cognitive Reliability and Error Analysis Method (CREAM). Predictions of possible erroneous actions were made for operators using different types of alarm systems. The data were collected as part of a large-scale experiment using professional nuclear power plant operators in a full scope simulator. The analysis showed that the predictions were correct in more than 70% of the cases, and also that the coverage of the predictions depended critically on the comprehensiveness of the preceding task analysis. PMID:10582035

  16. Pronominal Case-Errors

    ERIC Educational Resources Information Center

    Kaper, Willem

    1976-01-01

    Contradicts a previous assertion by C. Tanz that children commit substitution errors usually using objective pronoun forms for nominative ones. Examples from Dutch and German provide evidence that substitutions are made in both directions. (CHK)

  17. Estimating Bias Error Distributions

    NASA Technical Reports Server (NTRS)

    Liu, Tian-Shu; Finley, Tom D.

    2001-01-01

    This paper formulates the general methodology for estimating the bias error distribution of a device in a measuring domain from less accurate measurements when a minimal number of standard values (typically two values) are available. A new perspective is that the bias error distribution can be found as a solution of an intrinsic functional equation in a domain. Based on this theory, the scaling- and translation-based methods for determining the bias error distribution arc developed. These methods are virtually applicable to any device as long as the bias error distribution of the device can be sufficiently described by a power series (a polynomial) or a Fourier series in a domain. These methods have been validated through computational simulations and laboratory calibration experiments for a number of different devices.

  18. Error-Compensated Telescope

    NASA Technical Reports Server (NTRS)

    Meinel, Aden B.; Meinel, Marjorie P.; Stacy, John E.

    1989-01-01

    Proposed reflecting telescope includes large, low-precision primary mirror stage and small, precise correcting mirror. Correcting mirror machined under computer control to compensate for error in primary mirror. Correcting mirror machined by diamond cutting tool. Computer analyzes interferometric measurements of primary mirror to determine shape of surface of correcting mirror needed to compensate for errors in wave front reflected from primary mirror and commands position and movement of cutting tool accordingly.

  19. Thermodynamics of Error Correction

    NASA Astrophysics Data System (ADS)

    Sartori, Pablo; Pigolotti, Simone

    2015-10-01

    Information processing at the molecular scale is limited by thermal fluctuations. This can cause undesired consequences in copying information since thermal noise can lead to errors that can compromise the functionality of the copy. For example, a high error rate during DNA duplication can lead to cell death. Given the importance of accurate copying at the molecular scale, it is fundamental to understand its thermodynamic features. In this paper, we derive a universal expression for the copy error as a function of entropy production and work dissipated by the system during wrong incorporations. Its derivation is based on the second law of thermodynamics; hence, its validity is independent of the details of the molecular machinery, be it any polymerase or artificial copying device. Using this expression, we find that information can be copied in three different regimes. In two of them, work is dissipated to either increase or decrease the error. In the third regime, the protocol extracts work while correcting errors, reminiscent of a Maxwell demon. As a case study, we apply our framework to study a copy protocol assisted by kinetic proofreading, and show that it can operate in any of these three regimes. We finally show that, for any effective proofreading scheme, error reduction is limited by the chemical driving of the proofreading reaction.

  20. 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.

  1. Human error in aviation operations

    NASA Technical Reports Server (NTRS)

    Nagel, David C.

    1988-01-01

    The role of human error in commercial and general aviation accidents and the techniques used to evaluate it are reviewed from a human-factors perspective. Topics addressed include the general decline in accidents per million departures since the 1960s, the increase in the proportion of accidents due to human error, methods for studying error, theoretical error models, and the design of error-resistant systems. Consideration is given to information acquisition and processing errors, visually guided flight, disorientation, instrument-assisted guidance, communication errors, decision errors, debiasing, and action errors.

  2. The National Geodetic Survey absolute gravity program

    NASA Astrophysics Data System (ADS)

    Peter, George; Moose, Robert E.; Wessells, Claude W.

    1989-03-01

    The National Geodetic Survey absolute gravity program will utilize the high precision afforded by the JILAG-4 instrument to support geodetic and geophysical research, which involves studies of vertical motions, identification and modeling of other temporal variations, and establishment of reference values. The scientific rationale of these objectives is given, the procedures used to collect gravity and environmental data in the field are defined, and the steps necessary to correct and remove unwanted environmental effects are stated. In addition, site selection criteria, methods of concomitant environmental data collection and relative gravity observations, and schedule and logistics are discussed.

  3. Characterization of the DARA solar absolute radiometer

    NASA Astrophysics Data System (ADS)

    Finsterle, W.; Suter, M.; Fehlmann, A.; Kopp, G.

    2011-12-01

    The Davos Absolute Radiometer (DARA) prototype is an Electrical Substitution Radiometer (ESR) which has been developed as a successor of the PMO6 type on future space missions and ground based TSI measurements. The DARA implements an improved thermal design of the cavity detector and heat sink assembly to minimize air-vacuum differences and to maximize thermal symmetry of measuring and compensating cavity. The DARA also employs an inverted viewing geometry to reduce internal stray light. We will report on the characterization and calibration experiments which were carried out at PMOD/WRC and LASP (TRF).

  4. Absolute calibration of the Auger fluorescence detectors

    SciTech Connect

    Bauleo, P.; Brack, J.; Garrard, L.; Harton, J.; Knapik, R.; Meyhandan, R.; Rovero, A.C.; Tamashiro, A.; Warner, D.

    2005-07-01

    Absolute calibration of the Pierre Auger Observatory fluorescence detectors uses a light source at the telescope aperture. The technique accounts for the combined effects of all detector components in a single measurement. The calibrated 2.5 m diameter light source fills the aperture, providing uniform illumination to each pixel. The known flux from the light source and the response of the acquisition system give the required calibration for each pixel. In the lab, light source uniformity is studied using CCD images and the intensity is measured relative to NIST-calibrated photodiodes. Overall uncertainties are presently 12%, and are dominated by systematics.

  5. Absolute angular positioning in ultrahigh vacuum

    SciTech Connect

    Schief, H.; Marsico, V.; Kern, K.

    1996-05-01

    Commercially available angular resolvers, which are routinely used in machine tools and robotics, are modified and adapted to be used under ultrahigh-vacuum (UHV) conditions. They provide straightforward and reliable measurements of angular positions for any kind of UHV sample manipulators. The corresponding absolute reproducibility is on the order of 0.005{degree}, whereas the relative resolution is better than 0.001{degree}, as demonstrated by high-resolution helium-reflectivity measurements. The mechanical setup and possible applications are discussed. {copyright} {ital 1996 American Institute of Physics.}

  6. Absolute Priority for a Vehicle in VANET

    NASA Astrophysics Data System (ADS)

    Shirani, Rostam; Hendessi, Faramarz; Montazeri, Mohammad Ali; Sheikh Zefreh, Mohammad

    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 absolute priority for an emergency vehicle. We use the idea of vehicular ad-hoc networking to reduce the imposed travelling time. Then, we simulate our proposed protocol and compare it with a centrally controlled traffic light system.

  7. Contouring error compensation on a micro coordinate measuring machine

    NASA Astrophysics Data System (ADS)

    Fan, Kuang-Chao; Wang, Hung-Yu; Ye, Jyun-Kuan

    2011-12-01

    In recent years, three-dimensional measurements of nano-technology researches have received a great attention in the world. Based on the high accuracy demand, the error compensation of measurement machine is very important. In this study, a high precision Micro-CMM (coordinate measuring machine) has been developed which is composed of a coplanar stage for reducing the Abbé error in the vertical direction, the linear diffraction grating interferometer (LDGI) as the position feedback sensor in nanometer resolution, and ultrasonic motors for position control. This paper presents the error compensation strategy including "Home accuracy" and "Position accuracy" in both axes. For the home error compensation, we utilize a commercial DVD pick-up head and its S-curve principle to accurately search the origin of each axis. For the positioning error compensation, the absolute positions relative to the home are calibrated by laser interferometer and the error budget table is stored for feed forward error compensation. Contouring error can thus be compensated if both the compensation of both X and Y positioning errors are applied. Experiments show the contouring accuracy can be controlled to within 50nm after compensation.

  8. Errata: Papers in Error Analysis.

    ERIC Educational Resources Information Center

    Svartvik, Jan, Ed.

    Papers presented at the symposium of error analysis in Lund, Sweden, in September 1972, approach error analysis specifically in its relation to foreign language teaching and second language learning. Error analysis is defined as having three major aspects: (1) the description of the errors, (2) the explanation of errors by means of contrastive…

  9. Absolute photometric calibration of detectors to 0.3 mmag using amplitude-stabilized lasers and a helium-cooled absolute radiometer

    NASA Technical Reports Server (NTRS)

    Miller, Peter J.

    1988-01-01

    Laser sources whose intensity is determined with a cryogenic electrical substitution radiometer are described. Detectors are then calibrated against this known flux, with an overall error of 0.028 percent (0.3 mmag). Ongoing research has produced laser intensity stabilizers with flicker and drift of less than 0.01 percent. Recently, the useful wavelength limit of these stabilizers have been extended to 1.65 microns by using a new modular technology and InGaAs detector systems. Data from Si photodiode calibration using the method of Zalewski and Geist are compared against an absolute cavity radiometer calibration as an internal check on the calibration system.

  10. Determination of the absolute contours of optical flats

    NASA Technical Reports Server (NTRS)

    Primak, W.

    1969-01-01

    Emersons procedure is used to determine true absolute contours of optical flats. Absolute contours of standard flats are determined and a comparison is then made between standard and unknown flats. Contour differences are determined by deviation of Fizeau fringe.

  11. Smoothing error pitfalls

    NASA Astrophysics Data System (ADS)

    von Clarmann, T.

    2014-09-01

    The difference due to the content of a priori information between a constrained retrieval and the true atmospheric state is usually represented by a diagnostic quantity called smoothing error. In this paper it is shown that, regardless of the usefulness of the smoothing error as a diagnostic tool in its own right, the concept of the smoothing error as a component of the retrieval error budget is questionable because it is not compliant with Gaussian error propagation. The reason for this is that the smoothing error does not represent the expected deviation of the retrieval from the true state but the expected deviation of the retrieval from the atmospheric state sampled on an arbitrary grid, which is itself a smoothed representation of the true state; in other words, to characterize the full loss of information with respect to the true atmosphere, the effect of the representation of the atmospheric state on a finite grid also needs to be considered. The idea of a sufficiently fine sampling of this reference atmospheric state is problematic because atmospheric variability occurs on all scales, implying that there is no limit beyond which the sampling is fine enough. Even the idealization of infinitesimally fine sampling of the reference state does not help, because the smoothing error is applied to quantities which are only defined in a statistical sense, which implies that a finite volume of sufficient spatial extent is needed to meaningfully discuss temperature or concentration. Smoothing differences, however, which play a role when measurements are compared, are still a useful quantity if the covariance matrix involved has been evaluated on the comparison grid rather than resulting from interpolation and if the averaging kernel matrices have been evaluated on a grid fine enough to capture all atmospheric variations that the instruments are sensitive to. This is, under the assumptions stated, because the undefined component of the smoothing error, which is the

  12. Compact disk error measurements

    NASA Technical Reports Server (NTRS)

    Howe, D.; Harriman, K.; Tehranchi, B.

    1993-01-01

    The objectives of this project are as follows: provide hardware and software that will perform simple, real-time, high resolution (single-byte) measurement of the error burst and good data gap statistics seen by a photoCD player read channel when recorded CD write-once discs of variable quality (i.e., condition) are being read; extend the above system to enable measurement of the hard decision (i.e., 1-bit error flags) and soft decision (i.e., 2-bit error flags) decoding information that is produced/used by the Cross Interleaved - Reed - Solomon - Code (CIRC) block decoder employed in the photoCD player read channel; construct a model that uses data obtained via the systems described above to produce meaningful estimates of output error rates (due to both uncorrected ECC words and misdecoded ECC words) when a CD disc having specific (measured) error statistics is read (completion date to be determined); and check the hypothesis that current adaptive CIRC block decoders are optimized for pressed (DAD/ROM) CD discs. If warranted, do a conceptual design of an adaptive CIRC decoder that is optimized for write-once CD discs.

  13. Standardization of the cumulative absolute velocity

    SciTech Connect

    O'Hara, T.F.; Jacobson, J.P. )

    1991-12-01

    EPRI NP-5930, A Criterion for Determining Exceedance of the Operating Basis Earthquake,'' was published in July 1988. As defined in that report, the Operating Basis Earthquake (OBE) is exceeded when both a response spectrum parameter and a second damage parameter, referred to as the Cumulative Absolute Velocity (CAV), are exceeded. In the review process of the above report, it was noted that the calculation of CAV could be confounded by time history records of long duration containing low (nondamaging) acceleration. Therefore, it is necessary to standardize the method of calculating CAV to account for record length. This standardized methodology allows consistent comparisons between future CAV calculations and the adjusted CAV threshold value based upon applying the standardized methodology to the data set presented in EPRI NP-5930. The recommended method to standardize the CAV calculation is to window its calculation on a second-by-second basis for a given time history. If the absolute acceleration exceeds 0.025g at any time during each one second interval, the earthquake records used in EPRI NP-5930 have been reanalyzed and the adjusted threshold of damage for CAV was found to be 0.16g-set.

  14. Absolute rates of hole transfer in DNA.

    PubMed

    Senthilkumar, Kittusamy; Grozema, Ferdinand C; Guerra, Célia Fonseca; Bickelhaupt, F Matthias; Lewis, Frederick D; Berlin, Yuri A; Ratner, Mark A; Siebbeles, Laurens D A

    2005-10-26

    Absolute rates of hole transfer between guanine nucleobases separated by one or two A:T base pairs in stilbenedicarboxamide-linked DNA hairpins were obtained by improved kinetic analysis of experimental data. The charge-transfer rates in four different DNA sequences were calculated using a density-functional-based tight-binding model and a semiclassical superexchange model. Site energies and charge-transfer integrals were calculated directly as the diagonal and off-diagonal matrix elements of the Kohn-Sham Hamiltonian, respectively, for all possible combinations of nucleobases. Taking into account the Coulomb interaction between the negative charge on the stilbenedicarboxamide linker and the hole on the DNA strand as well as effects of base pair twisting, the relative order of the experimental rates for hole transfer in different hairpins could be reproduced by tight-binding calculations. To reproduce quantitatively the absolute values of the measured rate constants, the effect of the reorganization energy was taken into account within the semiclassical superexchange model for charge transfer. The experimental rates could be reproduced with reorganization energies near 1 eV. The quantum chemical data obtained were used to discuss charge carrier mobility and hole-transport equilibria in DNA. PMID:16231945

  15. Transient absolute robustness in stochastic biochemical networks.

    PubMed

    Enciso, German A

    2016-08-01

    Absolute 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 time 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 times, as the total protein concentrations grow to infinity. In particular, the stochastic system retains a transient, absolutely 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

  16. Absolute Electron Extraction Efficiency of Liquid Xenon

    NASA Astrophysics Data System (ADS)

    Kamdin, Katayun; Mizrachi, Eli; Morad, James; Sorensen, Peter

    2016-03-01

    Dual phase liquid/gas xenon time 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 absolute, assuming efficiency plateaus at 100%. I will present an absolute EEE measurement with a small liquid/gas xenon TPC test bed located at Lawrence Berkeley National Laboratory.

  17. Sentinel-2/MSI absolute calibration: first results

    NASA Astrophysics Data System (ADS)

    Lonjou, V.; Lachérade, S.; Fougnie, B.; Gamet, P.; Marcq, S.; Raynaud, J.-L.; Tremas, T.

    2015-10-01

    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 absolute 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 accuracy of the absolute 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.

  18. Absolute Spectrophotometry of 237 Open Cluster Stars

    NASA Astrophysics Data System (ADS)

    Clampitt, L.; Burstein, D.

    1994-12-01

    We present absolute spectrophotometry of 237 stars in 7 nearby open clusters: Hyades, Pleiades, Alpha Persei, Praesepe, Coma Berenices, IC 4665, and M 39. The observations were taken using the Wampler single-channel scanner (Wampler 1966) on the Crossley 0.9m telescope at Lick Observatory from July 1973 through December 1974. 21 bandpasses spanning the spectral range 3500 Angstroms to 7780 Angstroms were observed for each star, with bandwiths ranging from 32Angstroms to 64 Angstroms. Data are standardized to the Hayes--Latham (1975) system. Our measurements are compared to filter colors on the Johnson BV, Stromgren ubvy, and Geneva U V B_1 B_2 V_1 G systems, as well as to spectrophotometry of a few stars published by Gunn, Stryker & Tinsley and in the Spectrophotometric Standards Catalog (Adelman; as distributed by the NSSDC). Both internal and external comparisons to the filter systems indicate a formal statistical accuracy per bandpass of 0.01 to 0.02 mag, with apparent larger ( ~ 0.03 mag) differences in absolute calibration between this data set and existing spectrophotometry. These data will comprise part of the spectrophotometry that will be used to calibrate the Beijing-Arizona-Taipei-Connecticut Color Survey of the Sky (see separate paper by Burstein et al. at this meeting).

  19. SAR image registration in absolute coordinates using GPS carrier phase position and velocity information

    SciTech Connect

    Burgett, S.; Meindl, M.

    1994-09-01

    It is useful in a variety of military and commercial application to accurately register the position of synthetic aperture radar (SAR) imagery in absolute coordinates. The two basic SAR measurements, range and doppler, can be used to solve for the position of the SAR image. Imprecise knowledge of the SAR collection platform`s position and velocity vectors introduce errors in the range and doppler measurements and can cause the apparent location of the SAR image on the ground to be in error by tens of meters. Recent advances in carrier phase GPS techniques can provide an accurate description of the collection vehicle`s trajectory during the image formation process. In this paper, highly accurate carrier phase GPS trajectory information is used in conjunction with SAR imagery to demonstrate a technique for accurate registration of SAR images in WGS-84 coordinates. Flight test data will be presented that demonstrates SAR image registration errors of less than 4 meters.

  20. Experimental Quantum Error Detection

    PubMed Central

    Jin, Xian-Min; Yi, Zhen-Huan; Yang, Bin; Zhou, Fei; Yang, Tao; Peng, Cheng-Zhi

    2012-01-01

    Faithful transmission of quantum information is a crucial ingredient in quantum communication networks. To overcome the unavoidable decoherence in a noisy channel, to date, many efforts have been made to transmit one state by consuming large numbers of time-synchronized ancilla states. However, such huge demands of quantum resources are hard to meet with current technology and this restricts practical applications. Here we experimentally demonstrate quantum error detection, an economical approach to reliably protecting a qubit against bit-flip errors. Arbitrary unknown polarization states of single photons and entangled photons are converted into time bins deterministically via a modified Franson interferometer. Noise arising in both 10 m and 0.8 km fiber, which induces associated errors on the reference frame of time bins, is filtered when photons are detected. The demonstrated resource efficiency and state independence make this protocol a promising candidate for implementing a real-world quantum communication network. PMID:22953047

  1. Measurement error revisited

    NASA Astrophysics Data System (ADS)

    Henderson, Robert K.

    1999-12-01

    It is widely accepted in the electronics industry that measurement gauge error variation should be no larger than 10% of the related specification window. In a previous paper, 'What Amount of Measurement Error is Too Much?', the author used a framework from the process industries to evaluate the impact of measurement error variation in terms of both customer and supplier risk (i.e., Non-conformance and Yield Loss). Application of this framework in its simplest form suggested that in many circumstances the 10% criterion might be more stringent than is reasonably necessary. This paper reviews the framework and results of the earlier work, then examines some of the possible extensions to this framework suggested in that paper, including variance component models and sampling plans applicable in the photomask and semiconductor businesses. The potential impact of imperfect process control practices will be examined as well.

  2. A Conceptual Approach to Absolute Value Equations and Inequalities

    ERIC Educational Resources Information Center

    Ellis, Mark W.; Bryson, Janet L.

    2011-01-01

    The absolute value learning objective in high school mathematics requires students to solve far more complex absolute value equations and inequalities. When absolute value problems become more complex, students often do not have sufficient conceptual understanding to make any sense of what is happening mathematically. The authors suggest that the…

  3. Using, Seeing, Feeling, and Doing Absolute Value for Deeper Understanding

    ERIC Educational Resources Information Center

    Ponce, Gregorio A.

    2008-01-01

    Using sticky notes and number lines, a hands-on activity is shared that anchors initial student thinking about absolute value. The initial point of reference should help students successfully evaluate numeric problems involving absolute value. They should also be able to solve absolute value equations and inequalities that are typically found in…

  4. 20 CFR 404.1205 - Absolute coverage groups.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Absolute coverage groups. 404.1205 Section... INSURANCE (1950- ) Coverage of Employees of State and Local Governments What Groups of Employees May Be Covered § 404.1205 Absolute coverage groups. (a) General. An absolute coverage group is a...

  5. On-Orbit Absolute Radiance Standard for Future IR Remote Sensing Instruments

    NASA Astrophysics Data System (ADS)

    Best, F. A.; Adler, D. P.; Pettersen, C.; Revercomb, H. E.; Gero, P. J.; Taylor, J. K.; Knuteson, R. O.; Perepezko, J. H.

    2010-12-01

    Future NASA infrared remote sensing missions, including the climate benchmark CLARREO mission will require better absolute measurement accuracy than now available, and will most certainly rely on the emerging capability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances with an absolute 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 absolute temperature uncertainties of better than 0.045K (3 sigma). Key elements of an On-Orbit Absolute 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 accuracy is being met. The underlying technologies include on-orbit absolute 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 accuracy validation for infrared remote sensing instruments.

  6. On-Orbit Absolute Radiance Standard for the Next Generation of IR Remote Sensing Instruments

    NASA Astrophysics Data System (ADS)

    Best, F. A.; Adler, D. P.; Pettersen, C.; Revercomb, H. E.; Gero, P.; Taylor, J. K.; Knuteson, R. O.; Perepezko, J. H.

    2011-12-01

    The next generation of infrared remote sensing satellite instrumentation, including climate benchmark missions will require better absolute measurement accuracy than now available, and will most certainly rely on the emerging capability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances with an absolute 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 absolute temperature uncertainties of better than 0.045K (k=3). Key elements of an On-Orbit Absolute Radiance Standard (OARS) meeting these stringent requirements have been demonstrated in the laboratory at the University of Wisconsin and are undergoing further refinement under the NASA Instrument Incubator Program (IIP). This work will culminate with an integrated subsystem that can provide on-orbit end-to-end radiometric accuracy validation for infrared remote sensing instruments. We present the new technologies that underlie the OARS and updated results of laboratory testing that demonstrate the required accuracy. The underlying technologies include on-orbit absolute 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.

  7. On-Orbit Absolute Radiance Standard for the Next Generation of IR Remote Sensing Instruments

    NASA Astrophysics Data System (ADS)

    Best, F. A.; Adler, D. P.; Pettersen, C.; Revercomb, H. E.; Gero, P. J.; Taylor, J. K.; Knuteson, R. O.; Perepezko, J. H.

    2012-12-01

    The next generation of infrared remote sensing satellite instrumentation, including climate benchmark missions will require better absolute measurement accuracy than now available, and will most certainly rely on the emerging capability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances with an absolute 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 absolute temperature uncertainties of better than 0.045K (k=3). Key elements of an On-Orbit Absolute Radiance Standard (OARS) meeting these stringent requirements have been demonstrated in the laboratory at the University of Wisconsin and are undergoing further refinement under the NASA Instrument Incubator Program (IIP). This work will culminate with an integrated subsystem that can provide on-orbit end-to-end radiometric accuracy validation for infrared remote sensing instruments. We present the new technologies that underlie the OARS and updated results of laboratory testing that demonstrate the required accuracy. The underlying technologies include on-orbit absolute 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.

  8. Surprise beyond prediction error

    PubMed Central

    Chumbley, Justin R; Burke, Christopher J; Stephan, Klaas E; Friston, Karl J; Tobler, Philippe N; Fehr, Ernst

    2014-01-01

    Surprise drives learning. Various neural “prediction error” signals are believed to underpin surprise-based reinforcement learning. Here, we report a surprise signal that reflects reinforcement learning but is neither un/signed reward prediction error (RPE) nor un/signed state prediction error (SPE). To exclude these alternatives, we measured surprise responses in the absence of RPE and accounted for a host of potential SPE confounds. This new surprise signal was evident in ventral striatum, primary sensory cortex, frontal poles, and amygdala. We interpret these findings via a normative model of surprise. PMID:24700400

  9. Evolution of error diffusion

    NASA Astrophysics Data System (ADS)

    Knox, Keith T.

    1999-10-01

    As we approach the new millennium, error diffusion is approaching the 25th anniversary of its invention. Because of its exceptionally high image quality, it continues to be a popular choice among digital halftoning algorithms. Over the last 24 years, many attempts have been made to modify and improve the algorithm--to eliminate unwanted textures and to extend it to printing media and color. Some of these modifications have been very successful and are in use today. This paper will review the history of the algorithm and its modifications. Three watershed events in the development of error diffusion will be described, together with the lessons learned along the way.

  10. Evolution of error diffusion

    NASA Astrophysics Data System (ADS)

    Knox, Keith T.

    1998-12-01

    As we approach the new millennium, error diffusion is approaching the 25th anniversary of its invention. Because of its exceptionally high image quality, it continues to be a popular choice among digital halftoning algorithms. Over the last 24 years, many attempts have been made to modify and improve the algorithm - to eliminate unwanted textures and to extend it to printing media and color. Some of these modifications have been very successful and are in use today. This paper will review the history of the algorithm and its modifications. Three watershed events in the development of error diffusion will be described, together with the lesions learned along the way.

  11. Error Free Software

    NASA Technical Reports Server (NTRS)

    1985-01-01

    A mathematical theory for development of "higher order" software to catch computer mistakes resulted from a Johnson Space Center contract for Apollo spacecraft navigation. Two women who were involved in the project formed Higher Order Software, Inc. to develop and market the system of error analysis and correction. They designed software which is logically error-free, which, in one instance, was found to increase productivity by 600%. USE.IT defines its objectives using AXES -- a user can write in English and the system converts to computer languages. It is employed by several large corporations.

  12. Absolute magnitudes and slope parameters of Pan-STARRS PS1 asteroids --- preliminary results

    NASA Astrophysics Data System (ADS)

    Vereš, P.; Jedicke, R.; Fitzsimmons, A.; Denneau, L.; Bolin, B.; Wainscoat, R.; Tonry, J.

    2014-07-01

    We present the study of absolute magnitude (H) and slope parameter (G) of 170,000 asteroids observed by the Pan-STARRS1 telescope during the period of 15 months within its 3-year all-sky survey mission. The exquisite photometry with photometric errors below 0.04 mag and well-defined filter and photometric system allowed to derive H and G with statistical and systematic errors. Our new approach lies in the Monte Carlo technique simulating rotation periods, amplitudes, and colors, and deriving most-likely H, G and their systematic errors. Comparison of H_M by Muinonen's phase function (Muinonen et al., 2010) with the Minor Planet Center database revealed a negative offset of 0.22±0.29 meaning that Pan-STARRS1 asteroids are fainter. We showed that the absolute magnitude derived by Muinonen's function is systematically larger on average by 0.14±0.29 and by 0.30±0.16 when assuming fixed slope parameter (G=0.15, G_{12}=0.53) than Bowell's absolute magnitude (Bowell et al., 1989). We also derived slope parameters of asteroids of known spectral types and showed a good agreement with the previous studies within the derived uncertainties. However, our systematic errors on G and G_{12} are significantly larger than in previous work, which is caused by poor temporal and phase coverage of vast majority of the detected asteroids. This disadvantage will vanish when full survey data will be available and ongoing extended and enhanced mission will provide new data.

  13. Absolute absorption on the potassium D lines: theory and experiment

    NASA Astrophysics Data System (ADS)

    Hanley, Ryan K.; Gregory, Philip D.; Hughes, Ifan G.; Cornish, Simon L.

    2015-10-01

    We present a detailed study of the absolute Doppler-broadened absorption of a probe beam scanned across the potassium D lines in a thermal vapour. Spectra using a weak probe were measured on the 4S \\to 4P transition and compared to the theoretical model of the electric susceptibility detailed by Zentile et al (2015 Comput. Phys. Commun. 189 162-74) in the code named ElecSus. Comparisons were also made on the 4S \\to 5P transition with an adapted version of ElecSus. This is the first experimental test of ElecSus on an atom with a ground state hyperfine splitting smaller than that of the Doppler width. An excellent agreement was found between ElecSus and experimental measurements at a variety of temperatures with rms errors ˜ {10}-3. We have also demonstrated the use of ElecSus as an atomic vapour thermometry tool, and present a possible new measurement technique of transition decay rates which we predict to have a precision of ˜3 {kHz}.

  14. Using absolute gravimeter data to determine vertical gravity gradients

    USGS Publications Warehouse

    Robertson, D.S.

    2001-01-01

    The position versus time data from a free-fall absolute gravimeter can be used to estimate the vertical gravity gradient in addition to the gravity value itself. Hipkin has reported success in estimating the vertical gradient value using a data set of unusually good quality. This paper explores techniques that may be applicable to a broader class of data that may be contaminated with "system response" errors of larger magnitude than were evident in the data used by Hipkin. This system response function is usually modelled as a sum of exponentially decaying sinusoidal components. The technique employed here involves combining the x0, v0 and g parameters from all the drops made during a site occupation into a single least-squares solution, and including the value of the vertical gradient and the coefficients of system response function in the same solution. The resulting non-linear equations must be solved iteratively and convergence presents some difficulties. Sparse matrix techniques are used to make the least-squares problem computationally tractable.

  15. Absolute Quantification of Individual Biomass Concentrations in a Methanogenic Coculture

    PubMed Central

    2014-01-01

    Identification of individual biomass concentrations is a crucial step towards an improved understanding of anaerobic digestion processes and mixed microbial conversions in general. The knowledge of individual biomass concentrations allows for the calculation of biomass specific conversion rates which form the basis of anaerobic digestion models. Only few attempts addressed the absolute quantification of individual biomass concentrations in methanogenic microbial ecosystems which has so far impaired the calculation of biomass specific conversion rates and thus model validation. This study proposes a quantitative PCR (qPCR) approach for the direct determination of individual biomass concentrations in methanogenic microbial associations by correlating the native qPCR signal (cycle threshold, Ct) to individual biomass concentrations (mg dry matter/L). Unlike existing methods, the proposed approach circumvents error-prone conversion factors that are typically used to convert gene copy numbers or cell concentrations into actual biomass concentrations. The newly developed method was assessed and deemed suitable for the determination of individual biomass concentrations in a defined coculture of Desulfovibrio sp. G11 and Methanospirillum hungatei JF1. The obtained calibration curves showed high accuracy, indicating that the new approach is well suited for any engineering applications where the knowledge of individual biomass concentrations is required. PMID:24949269

  16. Weighted Wilcoxon-type Smoothly Clipped Absolute Deviation Method

    PubMed Central

    Wang, Lan; Li, Runze

    2009-01-01

    Summary Shrinkage-type variable selection procedures have recently seen increasing applications in biomedical research. However, their performance can be adversely influenced by outliers in either the response or the covariate space. This paper proposes a weighted Wilcoxon-type smoothly clipped absolute deviation (WW-SCAD) method, which deals with robust variable selection and robust estimation simultaneously. The new procedure can be conveniently implemented with the statistical software R. We establish that the WW-SCAD correctly identifies the set of zero coefficients with probability approaching one and estimates the nonzero coefficients with the rate n−1/2. Moreover, with appropriately chosen weights the WW-SCAD is robust with respect to outliers in both the x and y directions. The important special case with constant weights yields an oracle-type estimator with high efficiency at the presence of heavier-tailed random errors. The robustness of the WW-SCAD is partly justified by its asymptotic performance under local shrinking contamination. We propose a BIC-type tuning parameter selector for the WW-SCAD. The performance of the WW-SCAD is demonstrated via simulations and by an application to a study that investigates the effects of personal characteristics and dietary factors on plasma beta-carotene level. PMID:18647294

  17. Absolute position total internal reflection microscopy with an optical tweezer

    PubMed Central

    Liu, Lulu; Woolf, Alexander; Rodriguez, Alejandro W.; Capasso, Federico

    2014-01-01

    A noninvasive, in situ calibration method for total internal reflection microscopy (TIRM) based on optical tweezing is presented, which greatly expands the capabilities of this technique. We show that by making only simple modifications to the basic TIRM sensing setup and procedure, a probe particle’s absolute position relative to a dielectric interface may be known with better than 10 nm precision out to a distance greater than 1 μm from the surface. This represents an approximate 10× improvement in error and 3× improvement in measurement range over conventional TIRM methods. The technique’s advantage is in the direct measurement of the probe particle’s scattering intensity vs. height profile in situ, rather than relying on assumptions, inexact system analogs, or detailed knowledge of system parameters for calibration. To demonstrate the improved versatility of the TIRM method in terms of tunability, precision, and range, we show our results for the hindered near-wall diffusion coefficient for a spherical dielectric particle. PMID:25512542

  18. Comparison of Using Relative and Absolute PCV Corrections in Short Baseline GNSS Observation Processing

    NASA Astrophysics Data System (ADS)

    Dawidowicz, Karol

    2011-01-01

    GNSS antenna phase center variations (PCV) are defined as shifts in positions depending on the observed elevation angle and azimuth to the satellite. When identical antennae are used in relative measurement the phase center variations will cancel out, particularly over short baselines. When different antennae are used, even on short baselines, ignoring these phase center variations can lead to serious (up to 10 cm) vertical errors. The only way to avoid these errors, when mixing different antenna types, is by applying antenna phase center variation models in processing. Till the 6th November 2006, the International GNSS Service used relative phase center models for GNSS antenna receivers. Then absolute calibration models, developed by the company "Geo++", started to be used. These models involved significant differences on the scale of GNSS networks compared to the VLBI and SLR measurements. The differences were due to the lack of the GNSS satellite antenna calibration models. When this problem was sufficiently resolved, the IGS decided to switch from relative to absolute models for both satellites and receivers. This decision caused significant variations to the results of the GNSS network solutions. The aim of this paper is to study the height differences in short baseline GNSS observations processing when different calibration models are used. The analysis was done using GNSS data collected at short baselines moved with different receiver antennas. The results of calculations show, that switching from relative to absolute receiver antenna PCV models has a significant effect on GNSS network solutions, particularly in high accuracy applications.

  19. VizieR Online Data Catalog: Absolute Proper motions Outside the Plane (APOP) (Qi+, 2015)

    NASA Astrophysics Data System (ADS)

    Qi, Z. X.; Yu, Y.; Bucciasrelli, B.; Lattanzi, M. G.; Smart, R. L.; Spagna, A.; McLean, B. J.; Tang, Z. H.; Jones, H. R. A.; Morbidelli, R.; Nicastro, L.; Vacchiato, A.

    2015-09-01

    The APOP is a absolute proper motion catalog achieved on the Digitized Sky Survey Schmidt plates data established by GSC-II project that outside the galactic plane (|b|>27°). The sky cover of this catalog is 22,525 square degree, the mean density is 4473 objects/sq.deg. and the magnitude limit is around R=20.8mag. The systematic errors of absolute proper motions related to the position, magnitude and color are practically all removed by using the extragalactic objects. The zero point error of absolute proper motions is less than 0.6mas/yr, and the accuracy is better than 4.0mas/yr for objects bright than R=18.5, and rises to 9.0mas/yr for objects with magnitude 18.5-30 degree and is not very well for others, the reason is that the epoch difference is large for Declination>-30° (45 years) but South than that is only around 12 years. It is fine for statistical studies for objects with Declination<-30° that people could find and remove obviously incorrect entries. (1 data file).

  20. Use of Absolute and Comparative Performance Feedback in Absolute and Comparative Judgments and Decisions

    ERIC Educational Resources Information Center

    Moore, Don A.; Klein, William M. P.

    2008-01-01

    Which matters more--beliefs about absolute ability or ability relative to others? This study set out to compare the effects of such beliefs on satisfaction with performance, self-evaluations, and bets on future performance. In Experiment 1, undergraduate participants were told they had answered 20% correct, 80% correct, or were not given their…

  1. Help prevent hospital errors

    MedlinePlus

    ... A.D.A.M. Editorial team. Related MedlinePlus Health Topics Medication Errors Patient Safety Browse the Encyclopedia A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission ... for online health information and services. Learn more about A.D. ...

  2. Orwell's Instructive Errors

    ERIC Educational Resources Information Center

    Julian, Liam

    2009-01-01

    In this article, the author talks about George Orwell, his instructive errors, and the manner in which Orwell pierced worthless theory, faced facts and defended decency (with fluctuating success), and largely ignored the tradition of accumulated wisdom that has rendered him a timeless teacher--one whose inadvertent lessons, while infrequently…

  3. Effects of confining pressure, pore pressure and temperature on absolute permeability. SUPRI TR-27

    SciTech Connect

    Gobran, B.D.; Ramey, H.J. Jr.; Brigham, W.E.

    1981-10-01

    This study investigates absolute permeability of consolidated sandstone and unconsolidated sand cores to distilled water as a function of the confining pressure on the core, the pore pressure of the flowing fluid and the temperature of the system. Since permeability measurements are usually made in the laboratory under conditions very different from those in the reservoir, it is important to know the effect of various parameters on the measured value of permeability. All studies on the effect of confining pressure on absolute permeability have found that when the confining pressure is increased, the permeability is reduced. The studies on the effect of temperature have shown much less consistency. This work contradicts the past Stanford studies by finding no effect of temperature on the absolute permeability of unconsolidated sand or sandstones to distilled water. The probable causes of the past errors are discussed. It has been found that inaccurate measurement of temperature at ambient conditions and non-equilibrium of temperature in the core can lead to a fictitious permeability reduction with temperature increase. The results of this study on the effect of confining pressure and pore pressure support the theory that as confining pressure is increased or pore pressure decreased, the permeability is reduced. The effects of confining pressure and pore pressure changes on absolute permeability are given explicitly so that measurements made under one set of confining pressure/pore pressure conditions in the laboratory can be extrapolated to conditions more representative of the reservoir.

  4. Absolute surface metrology by differencing spatially shifted maps from a phase-shifting interferometer.

    PubMed

    Bloemhof, E E

    2010-07-15

    Surface measurements of precision optics are commonly made with commercially available phase-shifting Fizeau interferometers that provide data relative to flat or spherical reference surfaces whose unknown errors are comparable to those of the surface being tested. A number of ingenious techniques provide surface measurements that are "absolute," rather than relative to any reference surface. Generally, these techniques require numerous measurements and the introduction of additional surfaces, but still yield absolute information only along certain lines over the surface of interest. A very simple alternative is presented here, in which no additional optics are required beyond the surface under test and the transmission flat (or sphere) defining the interferometric reference surface. The optic under test is measured in three positions, two of which have small lateral shifts along orthogonal directions, nominally comparable to the transverse spatial resolution of the interferometer. The phase structure in the reference surface then cancels out when these measurements are subtracted in pairs, providing a grid of absolute surface height differences between neighboring resolution elements of the surface under test. The full absolute surface, apart from overall phase and tip/tilt, is then recovered by standard wavefront reconstruction techniques. PMID:20634825

  5. First Absolutely Calibrated Localized Measurements of Ion Velocity in the MST in Locked and Rotating Plasmas

    NASA Astrophysics Data System (ADS)

    Baltzer, M.; Craig, D.; den Hartog, D. J.; Nornberg, M. D.; Munaretto, S.

    2015-11-01

    An Ion Doppler Spectrometer (IDS) is used on MST for high time-resolution passive and active measurements of impurity ion emission. Absolutely calibrated measurements of flow are difficult because the spectrometer records data within 0.3 nm of the C+5 line of interest, and commercial calibration lamps do not produce lines in this narrow range . A novel optical system was designed to absolutely calibrate the IDS. The device uses an UV LED to produce a broad emission curve in the desired region. A Fabry-Perot etalon filters this light, cutting transmittance peaks into the pattern of the LED emission. An optical train of fused silica lenses focuses the light into the IDS with f/4. A holographic diffuser blurs the light cone to increase homogeneity. Using this light source, the absolute Doppler shift of ion emissions can be measured in MST plasmas. In combination with charge exchange recombination spectroscopy, localized ion velocities can now be measured. Previously, a time-averaged measurement along the chord bisecting the poloidal plane was used to calibrate the IDS; the quality of these central chord calibrations can be characterized with our absolute calibration. Calibration errors may also be quantified and minimized by optimizing the curve-fitting process. Preliminary measurements of toroidal velocity in locked and rotating plasmas will be shown. This work has been supported by the US DOE.

  6. In situ measurement of leaf chlorophyll concentration: analysis of the optical/absolute relationship.

    PubMed

    Parry, Christopher; Blonquist, J Mark; Bugbee, Bruce

    2014-11-01

    In situ optical meters are widely used to estimate leaf chlorophyll concentration, but non-uniform chlorophyll distribution causes optical measurements to vary widely among species for the same chlorophyll concentration. Over 30 studies have sought to quantify the in situ/in vitro (optical/absolute) relationship, but neither chlorophyll extraction nor measurement techniques for in vitro analysis have been consistent among studies. Here we: (1) review standard procedures for measurement of chlorophyll; (2) estimate the error associated with non-standard procedures; and (3) implement the most accurate methods to provide equations for conversion of optical to absolute chlorophyll for 22 species grown in multiple environments. Tests of five Minolta (model SPAD-502) and 25 Opti-Sciences (model CCM-200) meters, manufactured from 1992 to 2013, indicate that differences among replicate models are less than 5%. We thus developed equations for converting between units from these meter types. There was no significant effect of environment on the optical/absolute chlorophyll relationship. We derive the theoretical relationship between optical transmission ratios and absolute chlorophyll concentration and show how non-uniform distribution among species causes a variable, non-linear response. These results link in situ optical measurements with in vitro chlorophyll concentration and provide insight to strategies for radiation capture among diverse species. PMID:24635697

  7. AN ACCURATE NEW METHOD OF CALCULATING ABSOLUTE MAGNITUDES AND K-CORRECTIONS APPLIED TO THE SLOAN FILTER SET

    SciTech Connect

    Beare, Richard; Brown, Michael J. I.; Pimbblet, Kevin

    2014-12-20

    We describe an accurate new method for determining absolute magnitudes, and hence also K-corrections, that is simpler than most previous methods, being based on a quadratic function of just one suitably chosen observed color. The method relies on the extensive and accurate new set of 129 empirical galaxy template spectral energy distributions from Brown et al. A key advantage of our method is that we can reliably estimate random errors in computed absolute magnitudes due to galaxy diversity, photometric error and redshift error. We derive K-corrections for the five Sloan Digital Sky Survey filters and provide parameter tables for use by the astronomical community. Using the New York Value-Added Galaxy Catalog, we compare our K-corrections with those from kcorrect. Our K-corrections produce absolute magnitudes that are generally in good agreement with kcorrect. Absolute griz magnitudes differ by less than 0.02 mag and those in the u band by ∼0.04 mag. The evolution of rest-frame colors as a function of redshift is better behaved using our method, with relatively few galaxies being assigned anomalously red colors and a tight red sequence being observed across the whole 0.0 < z < 0.5 redshift range.

  8. Challenge and Error: Critical Events and Attention-Related Errors

    ERIC Educational Resources Information Center

    Cheyne, James Allan; Carriere, Jonathan S. A.; Solman, Grayden J. F.; Smilek, Daniel

    2011-01-01

    Attention lapses resulting from reactivity to task challenges and their consequences constitute a pervasive factor affecting everyday performance errors and accidents. A bidirectional model of attention lapses (error [image omitted] attention-lapse: Cheyne, Solman, Carriere, & Smilek, 2009) argues that errors beget errors by generating attention…

  9. Absolute calibration of ultraviolet filter photometry

    NASA Technical Reports Server (NTRS)

    Bless, R. C.; Fairchild, T.; Code, A. D.

    1972-01-01

    The essential features of the calibration procedure can be divided into three parts. First, the shape of the bandpass of each photometer was determined by measuring the transmissions of the individual optical components and also by measuring the response of the photometer as a whole. Secondly, each photometer was placed in the essentially-collimated synchrotron radiation bundle maintained at a constant intensity level, and the output signal was determined from about 100 points on the objective. Finally, two or three points on the objective were illuminated by synchrotron radiation at several different intensity levels covering the dynamic range of the photometers. The output signals were placed on an absolute basis by the electron counting technique described earlier.

  10. MAGSAT: Vector magnetometer absolute sensor alignment determination

    NASA Technical Reports Server (NTRS)

    Acuna, M. H.

    1981-01-01

    A procedure is described for accurately determining the absolute 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 accuracies 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.

  11. Absolute Measurement of Electron Cloud Density

    SciTech Connect

    Covo, M K; Molvik, A W; Cohen, R H; Friedman, A; Seidl, P A; Logan, G; Bieniosek, F; Baca, D; Vay, J; Orlando, E; Vujic, J L

    2007-06-21

    Beam interaction with background gas and walls produces ubiquitous clouds of stray electrons that frequently limit the performance of particle accelerator and storage rings. Counterintuitively we obtained the electron cloud accumulation by measuring the expelled ions that are originated from the beam-background gas interaction, rather than by measuring electrons that reach the walls. The kinetic ion energy measured with a retarding field analyzer (RFA) maps the depressed beam space-charge potential and provides the dynamic electron cloud density. Clearing electrode current measurements give the static electron cloud background that complements and corroborates with the RFA measurements, providing an absolute measurement of electron cloud density during a 5 {micro}s duration beam pulse in a drift region of the magnetic transport section of the High-Current Experiment (HCX) at LBNL.

  12. Absolute instability of a viscous hollow jet

    NASA Astrophysics Data System (ADS)

    Gañán-Calvo, Alfonso M.

    2007-02-01

    An investigation of the spatiotemporal stability of hollow jets in unbounded coflowing liquids, using a general dispersion relation previously derived, shows them to be absolutely unstable for all physical values of the Reynolds and Weber numbers. The roots of the symmetry breakdown with respect to the liquid jet case, and the validity of asymptotic models are here studied in detail. Asymptotic analyses for low and high Reynolds numbers are provided, showing that old and well-established limiting dispersion relations [J. W. S. Rayleigh, The Theory of Sound (Dover, New York, 1945); S. Chandrasekhar, Hydrodynamic and Hydromagnetic Stability (Dover, New York, 1961)] should be used with caution. In the creeping flow limit, the analysis shows that, if the hollow jet is filled with any finite density and viscosity fluid, a steady jet could be made arbitrarily small (compatible with the continuum hypothesis) if the coflowing liquid moves faster than a critical velocity.

  13. Swarm's Absolute Scalar Magnetometer metrological performances

    NASA Astrophysics Data System (ADS)

    Leger, J.; Fratter, I.; Bertrand, F.; Jager, T.; Morales, S.

    2012-12-01

    The Absolute 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 accuracy, 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.

  14. Absolute nonlocality via distributed computing without communication

    NASA Astrophysics Data System (ADS)

    Czekaj, Ł.; Pawłowski, M.; Vértesi, T.; Grudka, A.; Horodecki, M.; Horodecki, R.

    2015-09-01

    Understanding the role that quantum entanglement plays as a resource in various information processing tasks is one of the crucial goals of quantum information theory. Here we propose an alternative perspective for studying quantum entanglement: distributed computation of functions without communication between nodes. To formalize this approach, we propose identity games. Surprisingly, despite no signaling, we obtain that nonlocal quantum strategies beat classical ones in terms of winning probability for identity games originating from certain bipartite and multipartite functions. Moreover we show that, for a majority of functions, access to general nonsignaling resources boosts success probability two times in comparison to classical ones for a number of large enough outputs. Because there are no constraints on the inputs and no processing of the outputs in the identity games, they detect very strong types of correlations: absolute nonlocality.

  15. Absolute and Trend Accuracy of a New Regional Oximeter in Healthy Volunteers During Controlled Hypoxia

    PubMed Central

    Paidy, Samata; Kashif, Faisal

    2014-01-01

    BACKGROUND: Traditional patient monitoring may not detect cerebral tissue hypoxia, and typical interventions may not improve tissue oxygenation. Therefore, monitoring cerebral tissue oxygen status with regional oximetry is being increasingly used by anesthesiologists and perfusionists during surgery. In this study, we evaluated absolute and trend accuracy of a new regional oximetry technology in healthy volunteers. METHODS: A near-infrared spectroscopy sensor connected to a regional oximetry system (O3TM, Masimo, Irvine, CA) was placed on the subject’s forehead, to provide continuous measurement of regional oxygen saturation (rSo2). Reference blood samples were taken from the radial artery and internal jugular bulb vein, at baseline and after a series of increasingly hypoxic states induced by altering the inspired oxygen concentration while maintaining normocapnic arterial carbon dioxide pressure (Paco2). Absolute and trend accuracy of the regional oximetry system was determined by comparing rSo2 against reference cerebral oxygen saturation (Savo2), that is calculated by combining arterial and venous saturations of oxygen in the blood samples. RESULTS: Twenty-seven subjects were enrolled. Bias (test method mean error), standard deviation of error, standard error of the mean, and root mean square accuracy (ARMS) of rSo2 compared to Savo2 were 0.4%, 4.0%, 0.3%, and 4.0%, respectively. The limits of agreement were 8.4% (95% confidence interval, 7.6%–9.3%) to −7.6% (95% confidence interval, −8.4% to −6.7%). Trend accuracy analysis yielded a relative mean error of 0%, with a standard deviation of 2.1%, a standard error of 0.1%, and an ARMS of 2.1%. Multiple regression analysis showed that age and skin color did not affect the bias (all P > 0.1). CONCLUSIONS: Masimo O3 regional oximetry provided absolute root-mean-squared error of 4% and relative root-mean-squared error of 2.1% in healthy volunteers undergoing controlled hypoxia. PMID:25405692

  16. The Implications for Higher-Accuracy Absolute Measurements for NGS and its GRAV-D Project

    NASA Astrophysics Data System (ADS)

    Childers, V. A.; Winester, D.; Roman, D. R.; Eckl, M. C.; Smith, D. A.

    2013-12-01

    Absolute and relative gravity measurements play an important role in the work of NOAA's National Geodetic Survey (NGS). When NGS decided to replace the US national vertical datum, the Gravity for the Redefinition of the American Vertical Datum (GRAV-D) project added a new dimension to the NGS gravity program. Airborne gravity collection would complement existing satellite and surface gravity data to allow the creation of a gravimetric geoid sufficiently accurate to form the basis of the new reference surface. To provide absolute gravity ties for the airborne surveys, initially new FG5 absolute measurements were made at existing absolute stations and relative measurements were used to transfer those measurements to excenters near the absolute mark and to the aircraft sensor height at the parking space. In 2011, NGS obtained a field-capable A10 absolute gravimeter from Micro-g LaCoste which became the basis of the support of the airborne surveys. Now A10 measurements are made at the aircraft location and transferred to sensor height. Absolute and relative gravity play other roles in GRAV-D. Comparison of surface data with new airborne collection will highlight surface surveys with bias or tilt errors and can provide enough information to repair or discard the data. We expect that areas of problem surface data may be re-measured. The GRAV-D project also plans to monitor the geoid in regions of rapid change and update the vertical datum when appropriate. Geoid change can result from glacial isostatic adjustment (GIA), tectonic change, and the massive drawdown of large scale aquifers. The NGS plan for monitoring these changes over time is still in its preliminary stages and is expected to rely primarily on the GRACE and GRACE Follow On satellite data in conjunction with models of GIA and tectonic change. We expect to make absolute measurements in areas of rapid change in order to verify model predictions. With the opportunities presented by rapid, highly accurate

  17. Ultraspectral Sounding Retrieval Error Budget and Estimation

    NASA Technical Reports Server (NTRS)

    Zhou, Daniel K.; Larar, Allen M.; Liu, Xu; Smith, William L.; Strow, L. Larrabee; Yang, Ping

    2011-01-01

    The ultraspectral infrared radiances obtained from satellite observations provide atmospheric, surface, and/or cloud information. The intent of the measurement of the thermodynamic state is the initialization of weather and climate models. Great effort has been given to retrieving and validating these atmospheric, surface, and/or cloud properties. Error Consistency Analysis Scheme (ECAS), through fast radiative transfer model (RTM) forward and inverse calculations, has been developed to estimate the error budget in terms of absolute and standard deviation of differences in both spectral radiance and retrieved geophysical parameter domains. The retrieval error is assessed through ECAS without assistance of other independent measurements such as radiosonde data. ECAS re-evaluates instrument random noise, and establishes the link between radiometric accuracy and retrieved geophysical parameter accuracy. ECAS can be applied to measurements of any ultraspectral instrument and any retrieval scheme with associated RTM. In this paper, ECAS is described and demonstration is made with the measurements of the METOP-A satellite Infrared Atmospheric Sounding Interferometer (IASI)..

  18. Photocephalometry: errors of projection and landmark location.

    PubMed

    Phillips, C; Greer, J; Vig, P; Matteson, S

    1984-09-01

    A method called photocephalometry was recently described for the possible soft-tissue evaluation of orthognathic surgery patients by the superimposition of coordinated cephalographs and photographs. A grid analysis was performed to determine the accuracy of the superimposition method. In addition, the reliability of landmark identification was analyzed by the method error of Baumrind and Frantz, using three replicates of twelve patients' photographs. Comparison of twenty-one grid intervals showed that the magnification of the photographic image for any given grid plane is not correlated to that of the radiographic image. Accurate comparisons between soft- and hard-tissue anatomy by simply superimposing the images are not feasible because of the difference in the enlargement factors between the photographs and x-ray films. As was noted by Baumrind and Frantz, a wide range exists in the variability of estimating the location of landmarks. Sixty-six percent of the lateral photographic landmarks and 57% of the frontal landmarks had absolute mean errors for all twelve patients that were less than or equal to 2.0 mm. In general, the envelope of error for most landmarks was not circular. Although the photocephalometric apparatus as described by Hohl and colleagues does not yield the desired quantitative correlation between hard and soft tissues, valuable quantitative information on soft tissue can be easily obtained with the standardization and replication possible with the camera setup and enlarged photographs. PMID:6591803

  19. Absolute phase-assisted three-dimensional data registration for a dual-camera structured light system

    SciTech Connect

    Zhang Song; Yau Shingtung

    2008-06-10

    For a three-dimensional shape measurement system with a single projector and multiple cameras, registering patches from different cameras is crucial. Registration usually involves a complicated and time-consuming procedure. We propose a new method that can robustly match different patches via absolute phase without significantly increasing its cost. For y and z coordinates, the transformations from one camera to the other are approximated as third-order polynomial functions of the absolute phase. The x coordinates involve only translations and scalings. These functions are calibrated and only need to be determined once. Experiments demonstrated that the alignment error is within RMS 0.7 mm.

  20. Estimation of the absolute position of mobile systems by an optoelectronic processor

    NASA Technical Reports Server (NTRS)

    Feng, Liqiang; Fainman, Yeshaiahu; Koren, Yoram

    1992-01-01

    A method that determine the absolute position of a mobile system with a hybrid optoelectronic processor has been developed. Position estimates are based on an analysis of circular landmarks that are detected by a TV camera attached to the mobile system. The difference between the known shape of the landmark and its image provides the information needed to determine the absolute position of the mobile system. For robust operation, the parameters of the landmark image are extracted at high speeds using an optical processor that performs an optical Hough transform. The coordinates of the mobile system are computed from these parameters in a digital co-processor using fast algorithms. Different sources of position estimation errors have also been analyzed, and consequent algorithms to improve the navigation performance of the mobile system have been developed and evaluated by both computer simulation and experiments.

  1. Absolute Position Sensing Based on a Robust Differential Capacitive Sensor with a Grounded Shield Window.

    PubMed

    Bai, Yang; Lu, Yunfeng; Hu, Pengcheng; Wang, Gang; Xu, Jinxin; Zeng, Tao; Li, Zhengkun; Zhang, Zhonghua; Tan, Jiubin

    2016-01-01

    A simple differential capacitive sensor is provided in this paper to measure the absolute positions of length measuring systems. By utilizing a shield window inside the differential capacitor, the measurement range and linearity range of the sensor can reach several millimeters. What is more interesting is that this differential capacitive sensor is only sensitive to one translational degree of freedom (DOF) movement, and immune to the vibration along the other two translational DOFs. In the experiment, we used a novel circuit based on an AC capacitance bridge to directly measure the differential capacitance value. The experimental result shows that this differential capacitive sensor has a sensitivity of 2 × 10(-4) pF/μm with 0.08 μm resolution. The measurement range of this differential capacitive sensor is 6 mm, and the linearity error are less than 0.01% over the whole absolute position measurement range. PMID:27187393

  2. The solar absolute spectral irradiance 1150-3173 A - May 17, 1982

    NASA Technical Reports Server (NTRS)

    Mount, G. H.; Rottman, G. J.

    1983-01-01

    The full-disk solar spectral irradiance in the spectral range 1150-3173 A was obtained from a rocket observation above White Sands Missile Range, NM, on May 17, 1982, half way in time between solar maximum and solar minimum. Comparison with measurements made during solar maximum in 1980 indicate a large decrease in the absolute solar irradiance at wavelengths below 1900 A to approximately solar minimum values. No change above 1900 A from solar maximum to this flight was observed to within the errors of the measurements. Irradiance values lower than the Broadfoot results in the 2100-2500 A spectral range are found, but excellent agreement with Broadfoot between 2500 and 3173 A is found. The absolute calibration of the instruments for this flight was accomplished at the National Bureau of Standards Synchrotron Radiation Facility which significantly improves calibration of solar measurements made in this spectral region.

  3. Absolute brightness temperature measurements at 3.5-mm wavelength. [of sun, Venus, Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    Ulich, B. L.; Rhodes, P. J.; Davis, J. H.; Hollis, J. M.

    1980-01-01

    Careful observations have been made at 86.1 GHz to derive the absolute brightness temperatures of the sun (7914 + or - 192 K), Venus (357.5 + or - 13.1 K), Jupiter (179.4 + or - 4.7 K), and Saturn (153.4 + or - 4.8 K) with a standard error of about three percent. This is a significant improvement in accuracy over previous results at millimeter wavelengths. A stable transmitter and novel superheterodyne receiver were constructed and used to determine the effective collecting area of the Millimeter Wave Observatory (MWO) 4.9-m antenna relative to a previously calibrated standard gain horn. The thermal scale was set by calibrating the radiometer with carefully constructed and tested hot and cold loads. The brightness temperatures may be used to establish an absolute calibration scale and to determine the antenna aperture and beam efficiencies of other radio telescopes at 3.5-mm wavelength.

  4. Frequency-scanning interferometry for dynamic absolute distance measurement using Kalman filter.

    PubMed

    Tao, Long; Liu, Zhigang; Zhang, Weibo; Zhou, Yangli

    2014-12-15

    We propose a frequency-scanning interferometry using the Kalman filtering technique for dynamic absolute distance measurement. Frequency-scanning interferometry only uses a single tunable laser driven by a triangle waveform signal for forward and backward optical frequency scanning. The absolute distance and moving speed of a target can be estimated by the present input measurement of frequency-scanning interferometry and the previously calculated state based on the Kalman filter algorithm. This method not only compensates for movement errors in conventional frequency-scanning interferometry, but also achieves high-precision and low-complexity dynamic measurements. Experimental results of dynamic measurements under static state, vibration and one-dimensional movement are presented. PMID:25503050

  5. Absolute Position Sensing Based on a Robust Differential Capacitive Sensor with a Grounded Shield Window

    PubMed Central

    Bai, Yang; Lu, Yunfeng; Hu, Pengcheng; Wang, Gang; Xu, Jinxin; Zeng, Tao; Li, Zhengkun; Zhang, Zhonghua; Tan, Jiubin

    2016-01-01

    A simple differential capacitive sensor is provided in this paper to measure the absolute positions of length measuring systems. By utilizing a shield window inside the differential capacitor, the measurement range and linearity range of the sensor can reach several millimeters. What is more interesting is that this differential capacitive sensor is only sensitive to one translational degree of freedom (DOF) movement, and immune to the vibration along the other two translational DOFs. In the experiment, we used a novel circuit based on an AC capacitance bridge to directly measure the differential capacitance value. The experimental result shows that this differential capacitive sensor has a sensitivity of 2 × 10−4 pF/μm with 0.08 μm resolution. The measurement range of this differential capacitive sensor is 6 mm, and the linearity error are less than 0.01% over the whole absolute position measurement range. PMID:27187393

  6. Simple and accurate empirical absolute volume calibration of a multi-sensor fringe projection system

    NASA Astrophysics Data System (ADS)

    Gdeisat, Munther; Qudeisat, Mohammad; AlSa`d, Mohammed; Burton, David; Lilley, Francis; Ammous, Marwan M. M.

    2016-05-01

    This paper suggests a novel absolute empirical calibration method for a multi-sensor fringe projection system. The optical setup of the projector-camera sensor can be arbitrary. The term absolute calibration here means that the centre of the three dimensional coordinates in the resultant calibrated volume coincides with a preset centre to the three-dimensional real-world coordinate system. The use of a zero-phase fringe marking spot is proposed to increase depth calibration accuracy, where the spot centre is determined with sub-pixel accuracy. Also, a new method is proposed for transversal calibration. Depth and transversal calibration methods have been tested using both single sensor and three-sensor fringe projection systems. The standard deviation of the error produced by this system is 0.25 mm. The calibrated volume produced by this method is 400 mm×400 mm×140 mm.

  7. Absolute response of Fuji imaging plate detectors to picosecond-electron bunches.

    PubMed

    Zeil, K; Kraft, S D; Jochmann, A; Kroll, F; Jahr, W; Schramm, U; Karsch, L; Pawelke, J; Hidding, B; Pretzler, G

    2010-01-01

    The characterization of the absolute number of electrons generated by laser wakefield acceleration often relies on absolutely calibrated FUJI imaging plates (IP), although their validity in the regime of extreme peak currents is untested. Here, we present an extensive study on the dependence of the sensitivity of BAS-SR and BAS-MS IP to picosecond electron bunches of varying charge of up to 60 pC, performed at the electron accelerator ELBE, making use of about three orders of magnitude of higher peak intensity than in prior studies. We demonstrate that the response of the IPs shows no saturation effect and that the BAS-SR IP sensitivity of 0.0081 photostimulated luminescence per electron number confirms surprisingly well data from previous works. However, the use of the identical readout system and handling procedures turned out to be crucial and, if unnoticed, may be an important error source. PMID:20113093

  8. Absolute response of Fuji imaging plate detectors to picosecond-electron bunches

    SciTech Connect

    Zeil, K.; Kraft, S. D.; Jochmann, A.; Kroll, F.; Jahr, W.; Schramm, U.; Karsch, L.; Pawelke, J.; Hidding, B.; Pretzler, G.

    2010-01-15

    The characterization of the absolute number of electrons generated by laser wakefield acceleration often relies on absolutely calibrated FUJI imaging plates (IP), although their validity in the regime of extreme peak currents is untested. Here, we present an extensive study on the dependence of the sensitivity of BAS-SR and BAS-MS IP to picosecond electron bunches of varying charge of up to 60 pC, performed at the electron accelerator ELBE, making use of about three orders of magnitude of higher peak intensity than in prior studies. We demonstrate that the response of the IPs shows no saturation effect and that the BAS-SR IP sensitivity of 0.0081 photostimulated luminescence per electron number confirms surprisingly well data from previous works. However, the use of the identical readout system and handling procedures turned out to be crucial and, if unnoticed, may be an important error source.

  9. [The error, source of learning].

    PubMed

    Joyeux, Stéphanie; Bohic, Valérie

    2016-05-01

    The error itself is not recognised as a fault. It is the intentionality which differentiates between an error and a fault. An error is unintentional while a fault is a failure to respect known rules. The risk of error is omnipresent in health institutions. Public authorities have therefore set out a series of measures to reduce this risk. PMID:27155272

  10. Imagery of Errors in Typing

    ERIC Educational Resources Information Center

    Rieger, Martina; Martinez, Fanny; Wenke, Dorit

    2011-01-01

    Using a typing task we investigated whether insufficient imagination of errors and error corrections is related to duration differences between execution and imagination. In Experiment 1 spontaneous error imagination was investigated, whereas in Experiment 2 participants were specifically instructed to imagine errors. Further, in Experiment 2 we…

  11. Neural Correlates of Reach Errors

    PubMed Central

    Hashambhoy, Yasmin; Rane, Tushar; Shadmehr, Reza

    2005-01-01

    Reach errors may be broadly classified into errors arising from unpredictable changes in target location, called target errors, and errors arising from miscalibration of internal models, called execution errors. Execution errors may be caused by miscalibration of dynamics (e.g.. when a force field alters limb dynamics) or by miscalibration of kinematics (e.g., when prisms alter visual feedback). While all types of errors lead to similar online corrections, we found that the motor system showed strong trial-by-trial adaptation in response to random execution errors but not in response to random target errors. We used fMRI and a compatible robot to study brain regions involved in processing each kind of error. Both kinematic and dynamic execution errors activated regions along the central and the post-central sulci and in lobules V, VI, and VIII of the cerebellum, making these areas possible sites of plastic changes in internal models for reaching. Only activity related to kinematic errors extended into parietal area 5. These results are inconsistent with the idea that kinematics and dynamics of reaching are computed in separate neural entities. In contrast, only target errors caused increased activity in the striatum and the posterior superior parietal lobule. The cerebellum and motor cortex were as strongly activated as with execution errors. These findings indicate a neural and behavioral dissociation between errors that lead to switching of behavioral goals, and errors that lead to adaptation of internal models of limb dynamics and kinematics. PMID:16251440

  12. Automatic Error Analysis Using Intervals

    ERIC Educational Resources Information Center

    Rothwell, E. J.; Cloud, M. J.

    2012-01-01

    A technique for automatic error analysis using interval mathematics is introduced. A comparison to standard error propagation methods shows that in cases involving complicated formulas, the interval approach gives comparable error estimates with much less effort. Several examples are considered, and numerical errors are computed using the INTLAB…

  13. The Insufficiency of Error Analysis

    ERIC Educational Resources Information Center

    Hammarberg, B.

    1974-01-01

    The position here is that error analysis is inadequate, particularly from the language-teaching point of view. Non-errors must be considered in specifying the learner's current command of the language, its limits, and his learning tasks. A cyclic procedure of elicitation and analysis, to secure evidence of errors and non-errors, is outlined.…

  14. Control by model error estimation

    NASA Technical Reports Server (NTRS)

    Likins, P. W.; Skelton, R. E.

    1976-01-01

    Modern control theory relies upon the fidelity of the mathematical model of the system. Truncated modes, external disturbances, and parameter errors in linear system models are corrected by augmenting to the original system of equations an 'error system' which is designed to approximate the effects of such model errors. A Chebyshev error system is developed for application to the Large Space Telescope (LST).

  15. Absolute testing of surface based on sub-aperture stitching interferometry

    NASA Astrophysics Data System (ADS)

    Jia, Xin; Xu, Fuchao; Xie, Weimin; Xing, Tingwen

    2015-02-01

    Large-aperture optical elements are widely employed in high-power laser system, astronomy, and outer-space technology. Sub-aperture stitching is an effective way to extend the lateral and vertical dynamic range of a conventional interferometer. Most of the commercial available sub-aperture stitching interferometers measure the surface with a standard lens that produces a reference wavefront, and the precision of the interferometer is generally limited by the standard lens. The test accuracy can be achieved by removing the error of reference surface by the absolute testing method. In our paper we use the different sub-apertures as the different flats to get the profile of the reference lens. Only two lens in the testing process which is fewer than the traditional 3-flat method. In the testing equipment, we add a reflective lens and a lens which can transparent and reflect to get the non rationally symmetric errors of the testing flat. The arithmetic is present in this paper which uses the absolute testing method to improve the testing accuracy of the sub-aperture stitching interferometers by removing the errors caused by reference surface.

  16. Manson's triple error.

    PubMed

    F, Delaporte

    2008-09-01

    The author discusses the significance, implications and limitations of Manson's work. How did Patrick Manson resolve some of the major problems raised by the filarial worm life cycle? The Amoy physician showed that circulating embryos could only leave the blood via the percutaneous route, thereby requiring a bloodsucking insect. The discovery of a new autonomous, airborne, active host undoubtedly had a considerable impact on the history of parasitology, but the way in which Manson formulated and solved the problem of the transfer of filarial worms from the body of the mosquito to man resulted in failure. This article shows how the epistemological transformation operated by Manson was indissociably related to a series of errors and how a major breakthrough can be the result of a series of false proposals and, consequently, that the history of truth often involves a history of error. PMID:18814729

  17. Modular error embedding

    DOEpatents

    Sandford, II, Maxwell T.; Handel, Theodore G.; Ettinger, J. Mark

    1999-01-01

    A method of embedding auxiliary information into the digital representation of host data containing noise in the low-order bits. The method applies to digital data representing analog signals, for example digital images. The method reduces the error introduced by other methods that replace the low-order bits with auxiliary information. By a substantially reverse process, the embedded auxiliary data can be retrieved easily by an authorized user through use of a digital key. The modular error embedding method includes a process to permute the order in which the host data values are processed. The method doubles the amount of auxiliary information that can be added to host data values, in comparison with bit-replacement methods for high bit-rate coding. The invention preserves human perception of the meaning and content of the host data, permitting the addition of auxiliary data in the amount of 50% or greater of the original host data.

  18. Error-Free Software

    NASA Technical Reports Server (NTRS)

    1989-01-01

    001 is an integrated tool suited for automatically developing ultra reliable models, simulations and software systems. Developed and marketed by Hamilton Technologies, Inc. (HTI), it has been applied in engineering, manufacturing, banking and software tools development. The software provides the ability to simplify the complex. A system developed with 001 can be a prototype or fully developed with production quality code. It is free of interface errors, consistent, logically complete and has no data or control flow errors. Systems can be designed, developed and maintained with maximum productivity. Margaret Hamilton, President of Hamilton Technologies, also directed the research and development of USE.IT, an earlier product which was the first computer aided software engineering product in the industry to concentrate on automatically supporting the development of an ultrareliable system throughout its life cycle. Both products originated in NASA technology developed under a Johnson Space Center contract.

  19. THE ABSOLUTE MAGNITUDE OF RRc VARIABLES FROM STATISTICAL PARALLAX

    SciTech Connect

    Kollmeier, Juna A.; Burns, Christopher R.; Thompson, Ian B.; Preston, George W.; Crane, Jeffrey D.; Madore, Barry F.; Morrell, Nidia; Prieto, José L.; Shectman, Stephen; Simon, Joshua D.; Villanueva, Edward; Szczygieł, Dorota M.; Gould, Andrew; Sneden, Christopher; Dong, Subo

    2013-09-20

    We present the first definitive measurement of the absolute magnitude of RR Lyrae c-type variable stars (RRc) determined purely from statistical parallax. We use a sample of 242 RRc variables selected from the All Sky Automated Survey for which high-quality light curves, photometry, and proper motions are available. We obtain high-resolution echelle spectra for these objects to determine radial velocities and abundances as part of the Carnegie RR Lyrae Survey. We find that M{sub V,RRc} = 0.59 ± 0.10 at a mean metallicity of [Fe/H] = –1.59. This is to be compared with previous estimates for RRab stars (M{sub V,RRab} = 0.76 ± 0.12) and the only direct measurement of an RRc absolute magnitude (RZ Cephei, M{sub V,RRc} = 0.27 ± 0.17). We find the bulk velocity of the halo relative to the Sun to be (W{sub π}, W{sub θ}, W{sub z} ) = (12.0, –209.9, 3.0) km s{sup –1} in the radial, rotational, and vertical directions with dispersions (σ{sub W{sub π}},σ{sub W{sub θ}},σ{sub W{sub z}}) = (150.4, 106.1, 96.0) km s{sup -1}. For the disk, we find (W{sub π}, W{sub θ}, W{sub z} ) = (13.0, –42.0, –27.3) km s{sup –1} relative to the Sun with dispersions (σ{sub W{sub π}},σ{sub W{sub θ}},σ{sub W{sub z}}) = (67.7,59.2,54.9) km s{sup -1}. Finally, as a byproduct of our statistical framework, we are able to demonstrate that UCAC2 proper-motion errors are significantly overestimated as verified by UCAC4.

  20. Error-correction coding

    NASA Technical Reports Server (NTRS)

    Hinds, Erold W. (Principal Investigator)

    1996-01-01

    This report describes the progress made towards the completion of a specific task on error-correcting coding. The proposed research consisted of investigating the use of modulation block codes as the inner code of a concatenated coding system in order to improve the overall space link communications performance. The study proposed to identify and analyze candidate codes that will complement the performance of the overall coding system which uses the interleaved RS (255,223) code as the outer code.

  1. Bayesian Error Estimation Functionals

    NASA Astrophysics Data System (ADS)

    Jacobsen, Karsten W.

    The challenge of approximating the exchange-correlation functional in Density Functional Theory (DFT) has led to the development of numerous different approximations of varying accuracy on different calculated properties. There is therefore a need for reliable estimation of prediction errors within the different approximation schemes to DFT. The Bayesian Error Estimation Functionals (BEEF) have been developed with this in mind. The functionals are constructed by fitting to experimental and high-quality computational databases for molecules and solids including chemisorption and van der Waals systems. This leads to reasonably accurate general-purpose functionals with particual focus on surface science. The fitting procedure involves considerations on how to combine different types of data, and applies Tikhonov regularization and bootstrap cross validation. The methodology has been applied to construct GGA and metaGGA functionals with and without inclusion of long-ranged van der Waals contributions. The error estimation is made possible by the generation of not only a single functional but through the construction of a probability distribution of functionals represented by a functional ensemble. The use of the functional ensemble is illustrated on compound heat of formation and by investigations of the reliability of calculated catalytic ammonia synthesis rates.

  2. Human Error In Complex Systems

    NASA Technical Reports Server (NTRS)

    Morris, Nancy M.; Rouse, William B.

    1991-01-01

    Report presents results of research aimed at understanding causes of human error in such complex systems as aircraft, nuclear powerplants, and chemical processing plants. Research considered both slips (errors of action) and mistakes (errors of intention), and influence of workload on them. Results indicated that: humans respond to conditions in which errors expected by attempting to reduce incidence of errors; and adaptation to conditions potent influence on human behavior in discretionary situations.

  3. Prospects for the Moon as an SI-Traceable Absolute Spectroradiometric Standard for Satellite Remote Sensing

    NASA Astrophysics Data System (ADS)

    Cramer, C. E.; Stone, T. C.; Lykke, K.; Woodward, J. T.

    2015-12-01

    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 accuracy better than 0.1 % per year with lunar calibration techniques. However, the Moon rarely is used as an absolute reference for on-orbit calibration, primarily due to uncertainties in the ROLO model absolute scale of 5%-10%. But this limitation lies only with the models - the Moon itself is radiometrically stable, and development of a high-accuracy absolute lunar reference is inherently feasible. A program has been undertaken by NIST to collect absolute measurements of the lunar spectral irradiance with absolute accuracy <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 times 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 time 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

  4. Gyrokinetic Statistical Absolute Equilibrium and Turbulence

    SciTech Connect

    Jian-Zhou Zhu and Gregory W. Hammett

    2011-01-10

    A paradigm based on the absolute equilibrium of Galerkin-truncated inviscid systems to aid in understanding turbulence [T.-D. Lee, "On some statistical properties of hydrodynamical and magnetohydrodynamical fields," Q. Appl. Math. 10, 69 (1952)] is taken to study gyrokinetic plasma turbulence: A finite set of Fourier modes of the collisionless gyrokinetic equations are kept and the statistical equilibria are calculated; possible implications for plasma turbulence in various situations are discussed. For the case of two spatial and one velocity dimension, in the calculation with discretization also of velocity v with N grid points (where N + 1 quantities are conserved, corresponding to an energy invariant and N entropy-related invariants), the negative temperature states, corresponding to the condensation of the generalized energy into the lowest modes, are found. This indicates a generic feature of inverse energy cascade. Comparisons are made with some classical results, such as those of Charney-Hasegawa-Mima in the cold-ion limit. There is a universal shape for statistical equilibrium of gyrokinetics in three spatial and two velocity dimensions with just one conserved quantity. Possible physical relevance to turbulence, such as ITG zonal flows, and to a critical balance hypothesis are also discussed.

  5. Absolute surface energy for zincblende semiconductors

    NASA Astrophysics Data System (ADS)

    Zhang, S. B.; Wei, Su-Huai

    2003-03-01

    Recent advance in nanosciences requires the determination of surface (or facet) energy of semiconductors, which is often difficult due to the polar nature of some of the most important surfaces such as the (111)A/(111)B surfaces. Several approaches have been developed in the past [1-3] to deal with the problem but an unambiguous division of the polar surface energies is yet to come [2]. Here we show that an accurate division is indeed possible for the zincblende semiconductors and will present the results for GaAs, ZnSe, and CuInSe2 [4], respectively. A general trend emerges, relating the absolute surface energy to the ionicity of the bulk materials. [1] N. Chetty and R. M. Martin, Phys. Rev. B 45, 6074 (1992). [2] N. Moll, et al., Phys. Rev. B 54, 8844 (1996). [3] S. Mankefors, Phys. Rev. B 59, 13151 (1999). [4] S. B. Zhang and S.-H. Wei, Phys. Rev. B 65, 081402 (2002).

  6. Climate Absolute Radiance and Refractivity Observatory (CLARREO)

    NASA Technical Reports Server (NTRS)

    Leckey, John P.

    2015-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) is a mission, led and developed by NASA, that will measure a variety of climate variables with an unprecedented accuracy 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 accuracy, including on orbit verification, to calibrate other space-based instrumentation, increasing their respective accuracy 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) accuracy. The FTS will achieve this accuracy using phase change cells to verify thermistor accuracy 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 accuracy of 0.3% (k = 2). The status of the instrumentation packages and potential mission options will be presented.

  7. Absolute decay width measurements in 16O

    NASA Astrophysics Data System (ADS)

    Wheldon, C.; Ashwood, N. I.; Barr, M.; Curtis, N.; Freer, M.; Kokalova, Tz; Malcolm, J. D.; Spencer, S. J.; Ziman, V. A.; Faestermann, Th; Krücken, R.; Wirth, H.-F.; Hertenberger, R.; Lutter, R.; Bergmaier, A.

    2012-09-01

    The reaction 126C(63Li, d)168O* at a 6Li bombarding energy of 42 MeV has been used to populate excited states in 16O. The deuteron ejectiles were measured using the high-resolution Munich Q3D spectrograph. A large-acceptance silicon-strip detector array was used to register the recoil and break-up products. This complete kinematic set-up has enabled absolute α-decay widths to be measured with high-resolution in the 13.9 to 15.9 MeV excitation energy regime in 16O; many for the first time. This energy region spans the 14.4 MeV four-α breakup threshold. Monte-Carlo simulations of the detector geometry and break-up processes yield detection efficiencies for the two dominant decay modes of 40% and 37% for the α+12C(g.s.) and a+12C(2+1) break-up channels respectively.

  8. Absolute spectrophotometry of northern compact planetary nebulae

    NASA Astrophysics Data System (ADS)

    Wright, S. A.; Corradi, R. L. M.; Perinotto, M.

    2005-06-01

    We present medium-dispersion spectra and narrowband images of six northern compact planetary nebulae (PNe): BoBn 1, DdDm 1, IC 5117, M 1-5, M 1-71, and NGC 6833. From broad-slit spectra, total absolute fluxes and equivalent widths were measured for all observable emission lines. High signal-to-noise emission line fluxes of Hα, Hβ, [Oiii], [Nii], and HeI may serve as emission line flux standards for northern hemisphere observers. From narrow-slit spectra, we derive systemic radial velocities. For four PNe, available emission line fluxes were measured with sufficient signal-to-noise to probe the physical properties of their electron densities, temperatures, and chemical abundances. BoBn 1 and DdDm 1, both type IV PNe, have an Hβ flux over three sigma away from previous measurements. We report the first abundance measurements of M 1-71. NGC 6833 measured radial velocity and galactic coordinates suggest that it is associated with the outer arm or possibly the galactic halo, and its low abundance ([O/H]=1.3× 10-4) may be indicative of low metallicity within that region.

  9. Evaluating a medical error taxonomy.

    PubMed Central

    Brixey, Juliana; Johnson, Todd R.; Zhang, Jiajie

    2002-01-01

    Healthcare has been slow in using human factors principles to reduce medical errors. The Center for Devices and Radiological Health (CDRH) recognizes that a lack of attention to human factors during product development may lead to errors that have the potential for patient injury, or even death. In response to the need for reducing medication errors, the National Coordinating Council for Medication Errors Reporting and Prevention (NCC MERP) released the NCC MERP taxonomy that provides a standard language for reporting medication errors. This project maps the NCC MERP taxonomy of medication error to MedWatch medical errors involving infusion pumps. Of particular interest are human factors associated with medical device errors. The NCC MERP taxonomy of medication errors is limited in mapping information from MEDWATCH because of the focus on the medical device and the format of reporting. PMID:12463789

  10. A rack-mounted precision waveguide-below-cutoff attenuator with an absolute electronic readout

    NASA Technical Reports Server (NTRS)

    Cook, C. C.

    1974-01-01

    A coaxial precision waveguide-below-cutoff attenuator is described which uses an absolute (unambiguous) electronic digital readout of displacement in inches in addition to the usual gear driven mechanical counter-dial readout in decibels. The attenuator is rack-mountable and has the input and output RF connectors in a fixed position. The attenuation rate for 55, 50, and 30 MHz operation is given along with a discussion of sources of errors. In addition, information is included to aid the user in making adjustments on the attenuator should it be damaged or disassembled for any reason.

  11. Absolute nuclear material assay using count distribution (LAMBDA) space

    DOEpatents

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

    2015-12-01

    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.

  12. Absolute nuclear material assay using count distribution (LAMBDA) space

    DOEpatents

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

    2012-06-05

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

  13. The absolute disparity anomaly and the mechanism of relative disparities.

    PubMed

    Chopin, Adrien; Levi, Dennis; Knill, David; Bavelier, Daphne

    2016-06-01

    There has been a long-standing debate about the mechanisms underlying the perception of stereoscopic depth and the computation of the relative disparities that it relies on. Relative disparities between visual objects could be computed in two ways: (a) using the difference in the object's absolute disparities (Hypothesis 1) or (b) using relative disparities based on the differences in the monocular separations between objects (Hypothesis 2). To differentiate between these hypotheses, we measured stereoscopic discrimination thresholds for lines with different absolute and relative disparities. Participants were asked to judge the depth of two lines presented at the same distance from the fixation plane (absolute disparity) or the depth between two lines presented at different distances (relative disparity). We used a single stimulus method involving a unique memory component for both conditions, and no extraneous references were available. We also measured vergence noise using Nonius lines. Stereo thresholds were substantially worse for absolute disparities than for relative disparities, and the difference could not be explained by vergence noise. We attribute this difference to an absence of conscious readout of absolute disparities, termed the absolute disparity anomaly. We further show that the pattern of correlations between vergence noise and absolute and relative disparity acuities can be explained jointly by the existence of the absolute disparity anomaly and by the assumption that relative disparity information is computed from absolute disparities (Hypothesis 1). PMID:27248566

  14. The absolute disparity anomaly and the mechanism of relative disparities

    PubMed Central

    Chopin, Adrien; Levi, Dennis; Knill, David; Bavelier, Daphne

    2016-01-01

    There has been a long-standing debate about the mechanisms underlying the perception of stereoscopic depth and the computation of the relative disparities that it relies on. Relative disparities between visual objects could be computed in two ways: (a) using the difference in the object's absolute disparities (Hypothesis 1) or (b) using relative disparities based on the differences in the monocular separations between objects (Hypothesis 2). To differentiate between these hypotheses, we measured stereoscopic discrimination thresholds for lines with different absolute and relative disparities. Participants were asked to judge the depth of two lines presented at the same distance from the fixation plane (absolute disparity) or the depth between two lines presented at different distances (relative disparity). We used a single stimulus method involving a unique memory component for both conditions, and no extraneous references were available. We also measured vergence noise using Nonius lines. Stereo thresholds were substantially worse for absolute disparities than for relative disparities, and the difference could not be explained by vergence noise. We attribute this difference to an absence of conscious readout of absolute disparities, termed the absolute disparity anomaly. We further show that the pattern of correlations between vergence noise and absolute and relative disparity acuities can be explained jointly by the existence of the absolute disparity anomaly and by the assumption that relative disparity information is computed from absolute disparities (Hypothesis 1). PMID:27248566

  15. Evaluation and Applications of the Prediction of Intensity Model Error (PRIME) Model

    NASA Astrophysics Data System (ADS)

    Bhatia, K. T.; Nolan, D. S.; Demaria, M.; Schumacher, A.

    2015-12-01

    Forecasters and end users of tropical cyclone (TC) intensity forecasts would greatly benefit from a reliable expectation of model error to counteract the lack of consistency in TC intensity forecast performance. As a first step towards producing error predictions to accompany each TC intensity forecast, Bhatia and Nolan (2013) studied the relationship between synoptic parameters, TC attributes, and forecast errors. In this study, we build on previous results of Bhatia and Nolan (2013) by testing the ability of the Prediction of Intensity Model Error (PRIME) model to forecast the absolute error and bias of four leading intensity models available for guidance in the Atlantic basin. PRIME forecasts are independently evaluated at each 12-hour interval from 12 to 120 hours during the 2007-2014 Atlantic hurricane seasons. The absolute error and bias predictions of PRIME are compared to their respective climatologies to determine their skill. In addition to these results, we will present the performance of the operational version of PRIME run during the 2015 hurricane season. PRIME verification results show that it can reliably anticipate situations where particular models excel, and therefore could lead to a more informed protocol for hurricane evacuations and storm preparations. These positive conclusions suggest that PRIME forecasts also have the potential to lower the error in the original intensity forecasts of each model. As a result, two techniques are proposed to develop a post-processing procedure for a multimodel ensemble based on PRIME. The first approach is to inverse-weight models using PRIME absolute error predictions (higher predicted absolute error corresponds to lower weights). The second multimodel ensemble applies PRIME bias predictions to each model's intensity forecast and the mean of the corrected models is evaluated. The forecasts of both of these experimental ensembles are compared to those of the equal-weight ICON ensemble, which currently

  16. a Portable Apparatus for Absolute Measurements of the Earth's Gravity.

    NASA Astrophysics Data System (ADS)

    Zumberge, Mark Andrew

    We have developed a new, portable apparatus for making absolute 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 times 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 accuracy 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.

  17. Speech Errors, Error Correction, and the Construction of Discourse.

    ERIC Educational Resources Information Center

    Linde, Charlotte

    Speech errors have been used in the construction of production models of the phonological and semantic components of language, and for a model of interactional processes. Errors also provide insight into how speakers plan discourse and syntactic structure,. Different types of discourse exhibit different types of error. The present data are taken…

  18. Absolutely lossless compression of medical images.

    PubMed

    Ashraf, Robina; Akbar, Muhammad

    2005-01-01

    Data in medical images is very large and therefore for storage and/or transmission of these images, compression is essential. A method is proposed which provides high compression ratios for radiographic images with no loss of diagnostic quality. In the approach an image is first compressed at a high compression ratio but with loss, and the error image is then compressed losslessly. The resulting compression is not only strictly lossless, but also expected to yield a high compression ratio, especially if the lossy compression technique is good. A neural network vector quantizer (NNVQ) is used as a lossy compressor, while for lossless compression Huffman coding is used. Quality of images is evaluated by comparing with standard compression techniques available. PMID:17281110

  19. Orion Absolute Navigation System Progress and Challenge

    NASA Technical Reports Server (NTRS)

    Holt, Greg N.; D'Souza, Christopher

    2012-01-01

    The absolute 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 timely 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.

  20. Evaluation of the Absolute Regional Temperature Potential

    NASA Technical Reports Server (NTRS)

    Shindell, D. T.

    2012-01-01

    The Absolute 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 time-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.

  1. Absolute determination of local tropospheric OH concentrations

    NASA Technical Reports Server (NTRS)

    Armerding, Wolfgang; Comes, Franz-Josef

    1994-01-01

    Long path absorption (LPA) according to Lambert Beer's law is a method to determine absolute 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 times 10(exp 5) OH per cm(exp 3) for an acquisition time 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.

  2. Absolute Radiometric Calibration of KOMPSAT-3A

    NASA Astrophysics Data System (ADS)

    Ahn, H. Y.; Shin, D. Y.; Kim, J. S.; Seo, D. C.; Choi, C. U.

    2016-06-01

    This paper presents a vicarious radiometric calibration of the Korea Multi-Purpose Satellite-3A (KOMPSAT-3A) performed by the Korea Aerospace Research Institute (KARI) and the Pukyong National University Remote Sensing Group (PKNU RSG) in 2015.The primary stages of this study are summarized as follows: (1) A field campaign to determine radiometric calibrated target fields was undertaken in Mongolia and South Korea. Surface reflectance data obtained in the campaign were input to a radiative transfer code that predicted at-sensor radiance. Through this process, equations and parameters were derived for the KOMPSAT-3A sensor to enable the conversion of calibrated DN to physical units, such as at-sensor radiance or TOA reflectance. (2) To validate the absolute calibration coefficients for the KOMPSAT-3A sensor, we performed a radiometric validation with a comparison of KOMPSAT-3A and Landsat-8 TOA reflectance using one of the six PICS (Libya 4). Correlations between top-of-atmosphere (TOA) radiances and the spectral band responses of the KOMPSAT-3A sensors at the Zuunmod, Mongolia and Goheung, South Korea sites were significant for multispectral bands. The average difference in TOA reflectance between KOMPSAT-3A and Landsat-8 image over the Libya 4, Libya site in the red-green-blue (RGB) region was under 3%, whereas in the NIR band, the TOA reflectance of KOMPSAT-3A was lower than the that of Landsat-8 due to the difference in the band passes of two sensors. The KOMPSAT-3Aensor includes a band pass near 940 nm that can be strongly absorbed by water vapor and therefore displayed low reflectance. Toovercome this, we need to undertake a detailed analysis using rescale methods, such as the spectral bandwidth adjustment factor.

  3. Design of piezoresistive MEMS absolute pressure sensor

    NASA Astrophysics Data System (ADS)

    Kumar, S.; Pant, B. D.

    2012-10-01

    MEMS pressure sensors are one of the most widely commercialized microsensors in the MEMS industry. They have a plethora of applications in various fields including the automobile, space, biomedical, aviation and military sectors. One of the simplest and most efficient methods in MEMS pressure sensors for measuring pressure is to use the phenomenon of piezoresistance. The piezoresistive effect causes change in the resistance of certain doped materials when they are subjected to stress, as a result of energy band deformation. Piezoresistive pressure sensors consist of piezoresistors placed over a thin diaphragm which deflects under the action of the pressure to be measured. The result of this deflection causes the piezoresistors to change their resistance due to the stress experienced by them. The change is converted into electrical signals and measured in order to find the value of applied pressure. In this work, a high range (30 Bar) pressure sensor is designed based on the principle of piezoresistivity. The inaccuracies in the analytical models that are generally used to model the pressure sensor diaphragm have also been analysed. Thus, the Finite Element Method (FEM) is adopted to optimize the pressure sensor for parameters like sensitivity and linearity. This is achieved by choosing the proper shape of piezoresistor, thickness of diaphragm and the position of the piezoresistor on the pressure sensor diaphragm. For the square diaphragm, sensitivity of 5.18 mV/V/Bar and a linearity error of 0.02% are obtained. For the circular diaphragm, sensitivity of 3.69 mV/V/Bar and a linearity error of 0.011% are obtained.

  4. Measurement of the Absolute Branching Fraction of D0 to K- pi+

    SciTech Connect

    Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J.P.; Poireau, V.; Prudent, X.; Tisserand, V.; Zghiche, A.; Garra Tico, J.; Grauges, E.; Lopez, L.; Palano, A.; Eigen, G.; Ofte, I.; Stugu, B.; Sun, L.; Abrams, G.S.; Battaglia, M.; Brown, D.N.; Button-Shafer, J.; /LBL, Berkeley /Birmingham U. /Ruhr U., Bochum /Bristol U. /British Columbia U. /Brunel U. /Novosibirsk, IYF /UC, Irvine /UCLA /UC, Riverside /UC, San Diego /UC, Santa Barbara /UC, Santa Cruz /Caltech /Cincinnati U. /Colorado U. /Colorado State U. /Dortmund U. /Munich, Tech. U. /Ecole Polytechnique /Edinburgh U. /Ferrara U. /Frascati /Genoa U. /Harvard U. /Heidelberg U. /Imperial Coll., London /Iowa U. /Iowa State U. /Johns Hopkins U. /Karlsruhe U. /Orsay, LAL /LLNL, Livermore /Liverpool U. /Queen Mary, U. of London /Royal Holloway, U. of London /Louisville U. /Manchester U. /Maryland U. /Massachusetts U., Amherst /MIT, LNS /McGill U. /Maryland U. /INFN, Milan /Mississippi U. /Montreal U. /Mt. Holyoke Coll. /Naples U. /NIKHEF, Amsterdam /Notre Dame U. /Ohio State U. /Oregon U. /Padua U. /Paris U., VI-VII /Pennsylvania U. /Perugia U. /Pisa U. /Prairie View A-M /Princeton U. /INFN, Rome /Rostock U. /Rutherford /DSM, DAPNIA, Saclay /South Carolina U. /SLAC /Stanford U., Phys. Dept. /SUNY, Albany /Tennessee U. /Texas U. /Texas U., Dallas /Turin U. /Trieste U. /Valencia U., IFIC /Victoria U. /Warwick U. /Wisconsin U., Madison /Yale U.

    2007-04-25

    The authors measure the absolute branching fraction for D{sup 0} {yields} K{sup -} {pi}{sup +} using partial reconstruction of {bar B}{sup 0} {yields} D*{sup +}X{ell}{sup -}{bar {nu}}{sub {ell}} decays, in which only the charged lepton and the pion from the decay D*{sup +} {yields} D{sup 0}{pi}{sup +} are used. Based on a data sample of 230 million B{bar B} pairs collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II asymmetric-energy B Factory at SLAC, they obtain {Beta}(D{sup 0} {yields} K{sup -}{pi}{sup +}) = (4.007 {+-} 0.037 {+-} 0.070)%, where the first error is statistical and the second error is systematic.

  5. Mid-infrared absolute spectral responsivity scale based on an absolute cryogenic radiometer and an optical parametric oscillator laser

    NASA Astrophysics Data System (ADS)

    Zhao, Kun; Shi, Xueshun; Chen, Haidong; Liu, Yulong; Liu, Changming; Chen, Kunfeng; Li, Ligong; Gan, Haiyong; Ma, Chong

    2016-06-01

    We are reporting on a laser-based absolute spectral responsivity scale in the mid-infrared spectral range. By using a mid-infrared tunable optical parametric oscillator as the laser source, the absolute responsivity scale has been established by calibrating thin-film thermopile detectors against an absolute cryogenic radiometer. The thin-film thermopile detectors can be then used as transfer standard detectors. The extended uncertainty of the absolute spectral responsivity measurement has been analyzed to be 0.58%–0.68% (k  =  2).

  6. Skylab water balance error analysis

    NASA Technical Reports Server (NTRS)

    Leonard, J. I.

    1977-01-01

    Estimates of the precision of the net water balance were obtained for the entire Skylab preflight and inflight phases as well as for the first two weeks of flight. Quantitative estimates of both total sampling errors and instrumentation errors were obtained. It was shown that measurement error is minimal in comparison to biological variability and little can be gained from improvement in analytical accuracy. In addition, a propagation of error analysis demonstrated that total water balance error could be accounted for almost entirely by the errors associated with body mass changes. Errors due to interaction between terms in the water balance equation (covariances) represented less than 10% of the total error. Overall, the analysis provides evidence that daily measurements of body water changes obtained from the indirect balance technique are reasonable, precise, and relaible. The method is not biased toward net retention or loss.

  7. Standard Errors for Matrix Correlations.

    ERIC Educational Resources Information Center

    Ogasawara, Haruhiko

    1999-01-01

    Derives the asymptotic standard errors and intercorrelations for several matrix correlations assuming multivariate normality for manifest variables and derives the asymptotic standard errors of the matrix correlations for two factor-loading matrices. (SLD)

  8. Developing control charts to review and monitor medication errors.

    PubMed

    Ciminera, J L; Lease, M P

    1992-03-01

    There is a need to monitor reported medication errors in a hospital setting. Because the quantity of errors vary due to external reporting, quantifying the data is extremely difficult. Typically, these errors are reviewed using classification systems that often have wide variations in the numbers per class per month. The authors recommend the use of control charts to review historical data and to monitor future data. The procedure they have adopted is a modification of schemes using absolute (i.e., positive) values of successive differences to estimate the standard deviation when only single incidence values are available in time rather than sample averages, and when many successive differences may be zero. PMID:10116719

  9. Uncertainty quantification and error analysis

    SciTech Connect

    Higdon, Dave M; Anderson, Mark C; Habib, Salman; Klein, Richard; Berliner, Mark; Covey, Curt; Ghattas, Omar; Graziani, Carlo; Seager, Mark; Sefcik, Joseph; Stark, Philip

    2010-01-01

    UQ studies all sources of error and uncertainty, including: systematic and stochastic measurement error; ignorance; limitations of theoretical models; limitations of numerical representations of those models; limitations on the accuracy and reliability of computations, approximations, and algorithms; and human error. A more precise definition for UQ is suggested below.

  10. Grammatical Errors and Communication Breakdown.

    ERIC Educational Resources Information Center

    Tomiyama, Machiko

    This study investigated the relationship between grammatical errors and communication breakdown by examining native speakers' ability to correct grammatical errors. The assumption was that communication breakdown exists to a certain degree if a native speaker cannot correct the error or if the correction distorts the information intended to be…

  11. Supplementary and Enrichment Series: Absolute Value. Teachers' Commentary. SP-25.

    ERIC Educational Resources Information Center

    Bridgess, M. Philbrick, Ed.

    This is one in a series of manuals for teachers using SMSG high school supplementary materials. The pamphlet includes commentaries on the sections of the student's booklet, answers to the exercises, and sample test questions. Topics covered include addition and multiplication in terms of absolute value, graphs of absolute value in the Cartesian…

  12. Supplementary and Enrichment Series: Absolute Value. SP-24.

    ERIC Educational Resources Information Center

    Bridgess, M. Philbrick, Ed.

    This is one in a series of SMSG supplementary and enrichment pamphlets for high school students. This series is designed to make material for the study of topics of special interest to students readily accessible in classroom quantity. Topics covered include absolute value, addition and multiplication in terms of absolute value, graphs of absolute…

  13. Novalis' Poetic Uncertainty: A "Bildung" with the Absolute

    ERIC Educational Resources Information Center

    Mika, Carl

    2016-01-01

    Novalis, the Early German Romantic poet and philosopher, had at the core of his work a mysterious depiction of the "absolute." The absolute is Novalis' name for a substance that defies precise knowledge yet calls for a tentative and sensitive speculation. How one asserts a truth, represents an object, and sets about encountering things…

  14. Absolute Humidity and the Seasonality of Influenza (Invited)

    NASA Astrophysics Data System (ADS)

    Shaman, J. L.; Pitzer, V.; Viboud, C.; Grenfell, B.; Goldstein, E.; Lipsitch, M.

    2010-12-01

    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 absolute 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 absolute humidity levels during the prior weeks. We then use an epidemiological model, in which observed absolute 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 absolute humidity alone is sufficient to produce this observed seasonality. These findings provide epidemiological support for the hypothesis that absolute 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 absolute humidity, are consistent with the general timing of pandemic influenza outbreaks observed for 2009 A/H1N1 in temperate regions. Indeed, absolute humidity conditions correctly identify the region of the United States vulnerable to a third, wintertime wave of pandemic influenza. These findings suggest that the timing of pandemic influenza outbreaks is controlled by a combination of absolute humidity conditions, levels of susceptibility and changes in population mixing and contact rates.

  15. Errors inducing radiation overdoses.

    PubMed

    Grammaticos, Philip C

    2013-01-01

    There is no doubt that equipments exposing radiation and used for therapeutic purposes should be often checked for possibly administering radiation overdoses to the patients. Technologists, radiation safety officers, radiologists, medical physicists, healthcare providers and administration should take proper care on this issue. "We must be beneficial and not harmful to the patients", according to the Hippocratic doctrine. Cases of radiation overdose are often reported. A series of cases of radiation overdoses have recently been reported. Doctors who were responsible, received heavy punishments. It is much better to prevent than to treat an error or a disease. A Personal Smart Card or Score Card has been suggested for every patient undergoing therapeutic and/or diagnostic procedures by the use of radiation. Taxonomy may also help. PMID:24251304

  16. Beta systems error analysis

    NASA Technical Reports Server (NTRS)

    1984-01-01

    The atmospheric backscatter coefficient, beta, measured with an airborne CO Laser Doppler Velocimeter (LDV) system operating in a continuous wave, focussed model is discussed. The Single Particle Mode (SPM) algorithm, was developed from concept through analysis of an extensive amount of data obtained with the system on board a NASA aircraft. The SPM algorithm is intended to be employed in situations where one particle at a time appears in the sensitive volume of the LDV. In addition to giving the backscatter coefficient, the SPM algorithm also produces as intermediate results the aerosol density and the aerosol backscatter cross section distribution. A second method, which measures only the atmospheric backscatter coefficient, is called the Volume Mode (VM) and was simultaneously employed. The results of these two methods differed by slightly less than an order of magnitude. The measurement uncertainties or other errors in the results of the two methods are examined.

  17. Medical device error.

    PubMed

    Goodman, Gerald R

    2002-12-01

    This article discusses principal concepts for the analysis, classification, and reporting of problems involving medical device technology. We define a medical device in regulatory terminology and define and discuss concepts and terminology used to distinguish the causes and sources of medical device problems. Database classification systems for medical device failure tracking are presented, as are sources of information on medical device failures. The importance of near-accident reporting is discussed to alert users that reported medical device errors are typically limited to those that have caused an injury or death. This can represent only a fraction of the true number of device problems. This article concludes with a summary of the most frequently reported medical device failures by technology type, clinical application, and clinical setting. PMID:12400632

  18. Karst Water System Investigated by Absolute Gravimetry

    NASA Astrophysics Data System (ADS)

    Quinif, Y.; Meus, P.; van Camp, M.; Kaufmann, O.; van Ruymbeke, M.; Vandiepenbeeck, M.; Camelbeeck, T.

    2006-12-01

    The highly anisotropic and heterogeneous hydrogeological characteristics of karst aquifers are difficult to characterize and present challenges for modeling of storage capacities. Little is known about the surface and groundwater interconnection, about the connection between the porous formations and the draining cave and conduits, and about the variability of groundwater volume within the system. Usually, an aquifer is considered as a black box, where water fluxes are monitored as input and output. However, water inflow and outflow are highly variable and cannot be measured directly. A recent project, begun in 2006 sought to constrain the water budget in a Belgian karst aquifer and to assess the porosity and water dynamics, combining absolute gravity (AG) measurements and piezometric levels around the Rochefort cave. The advantage of gravity measurements is that they integrate all the subsystems in the karst system. This is not the case with traditional geophysical tools like boring or monitoring wells, which are soundings affected by their near environment and its heterogeneity. The investigated cave results from the meander cutoff system of the Lomme River. The main inputs are swallow holes of the river crossing the limestone massif. The river is canalized and the karst system is partly disconnected from the hydraulic system. In February and March 2006, when the river spilled over its dyke and sank into the most important swallow hole, this resulted in dramatic and nearly instantaneous increases in the piezometric levels in the cave, reaching up to 13 meters. Meanwhile, gravity increased by 50 and 90 nms-2 in February and March, respectively. A first conclusion is that during these sudden floods, the pores and fine fissures were poorly connected with the enlarged fractures, cave, and conduits. With a rise of 13 meters in the water level and a 5% porosity, a gravity change of 250 nms-2 should have been expected. This moderate gravity variation suggests either a

  19. Absolute radiometric calibration of advanced remote sensing systems

    NASA Technical Reports Server (NTRS)

    Slater, P. N.

    1982-01-01

    The distinction between the uses of relative and absolute spectroradiometric calibration of remote sensing systems is discussed. The advantages of detector-based absolute calibration are described, and the categories of relative and absolute system calibrations are listed. The limitations and problems associated with three common methods used for the absolute calibration of remote sensing systems are addressed. Two methods are proposed for the in-flight absolute calibration of advanced multispectral linear array systems. One makes use of a sun-illuminated panel in front of the sensor, the radiance of which is monitored by a spectrally flat pyroelectric radiometer. The other uses a large, uniform, high-radiance reference ground surface. The ground and atmospheric measurements required as input to a radiative transfer program to predict the radiance level at the entrance pupil of the orbital sensor are discussed, and the ground instrumentation is described.

  20. Testing the quasi-absolute method in photon activation analysis

    SciTech Connect

    Sun, Z. J.; Wells, D.; Starovoitova, V.; Segebade, C.

    2013-04-19

    In photon activation analysis (PAA), relative methods are widely used because of their accuracy and precision. Absolute methods, which are conducted without any assistance from calibration materials, are seldom applied for the difficulty in obtaining photon flux in measurements. This research is an attempt to perform a new absolute approach in PAA - quasi-absolute method - by retrieving photon flux in the sample through Monte Carlo simulation. With simulated photon flux and database of experimental cross sections, it is possible to calculate the concentration of target elements in the sample directly. The QA/QC procedures to solidify the research are discussed in detail. Our results show that the accuracy of the method for certain elements is close to a useful level in practice. Furthermore, the future results from the quasi-absolute method can also serve as a validation technique for experimental data on cross sections. The quasi-absolute method looks promising.

  1. Learning in the temporal bisection task: Relative or absolute?

    PubMed

    de Carvalho, Marilia Pinheiro; Machado, Armando; Tonneau, François

    2016-01-01

    We examined whether temporal learning in a bisection task is absolute or relational. Eight pigeons learned to choose a red key after a t-seconds sample and a green key after a 3t-seconds sample. To determine whether they had learned a relative mapping (short→Red, long→Green) or an absolute mapping (t-seconds→Red, 3t-seconds→Green), the pigeons then learned a series of new discriminations in which either the relative or the absolute mapping was maintained. Results showed that the generalization gradient obtained at the end of a discrimination predicted the pattern of choices made during the first session of a new discrimination. Moreover, most acquisition curves and generalization gradients were consistent with the predictions of the learning-to-time model, a Spencean model that instantiates absolute learning with temporal generalization. In the bisection task, the basis of temporal discrimination seems to be absolute, not relational. PMID:26752233

  2. Errors and correction of precipitation measurements in China

    NASA Astrophysics Data System (ADS)

    Ren, Zhihua; Li, Mingqin

    2007-05-01

    In order to discover the range of various errors in Chinese precipitation measurements and seek a correction method, 30 precipitation evaluation stations were set up countrywide before 1993. All the stations are reference stations in China. To seek a correction method for wind-induced error, a precipitation correction instrument called the “horizontal precipitation gauge” was devised beforehand. Field intercomparison observations regarding 29,000 precipitation events have been conducted using one pit gauge, two elevated operational gauges and one horizontal gauge at the above 30 stations. The range of precipitation measurement errors in China is obtained by analysis of intercomparison measurement results. The distribution of random errors and systematic errors in precipitation measurements are studied in this paper. A correction method, especially for wind-induced errors, is developed. The results prove that a correlation of power function exists between the precipitation amount caught by the horizontal gauge and the absolute difference of observations implemented by the operational gauge and pit gauge. The correlation coefficient is 0.99. For operational observations, precipitation correction can be carried out only by parallel observation with a horizontal precipitation gauge. The precipitation accuracy after correction approaches that of the pit gauge. The correction method developed is simple and feasible.

  3. Integrated Navigation System Design for Micro Planetary Rovers: Comparison of Absolute Heading Estimation Algorithms and Nonlinear Filtering

    PubMed Central

    Ilyas, Muhammad; Hong, Beomjin; Cho, Kuk; Baeg, Seung-Ho; Park, Sangdeok

    2016-01-01

    This paper provides algorithms to fuse relative and absolute microelectromechanical systems (MEMS) navigation sensors, suitable for micro planetary rovers, to provide a more accurate estimation of navigation information, specifically, attitude and position. Planetary rovers have extremely slow speed (~1 cm/s) and lack conventional navigation sensors/systems, hence the general methods of terrestrial navigation may not be applicable to these applications. While relative attitude and position can be tracked in a way similar to those for ground robots, absolute navigation information is hard to achieve on a remote celestial body, like Moon or Mars, in contrast to terrestrial applications. In this study, two absolute attitude estimation algorithms were developed and compared for accuracy and robustness. The estimated absolute attitude was fused with the relative attitude sensors in a framework of nonlinear filters. The nonlinear Extended Kalman filter (EKF) and Unscented Kalman filter (UKF) were compared in pursuit of better accuracy and reliability in this nonlinear estimation problem, using only on-board low cost MEMS sensors. Experimental results confirmed the viability of the proposed algorithms and the sensor suite, for low cost and low weight micro planetary rovers. It is demonstrated that integrating the relative and absolute navigation MEMS sensors reduces the navigation errors to the desired level. PMID:27223293

  4. Integrated Navigation System Design for Micro Planetary Rovers: Comparison of Absolute Heading Estimation Algorithms and Nonlinear Filtering.

    PubMed

    Ilyas, Muhammad; Hong, Beomjin; Cho, Kuk; Baeg, Seung-Ho; Park, Sangdeok

    2016-01-01

    This paper provides algorithms to fuse relative and absolute microelectromechanical systems (MEMS) navigation sensors, suitable for micro planetary rovers, to provide a more accurate estimation of navigation information, specifically, attitude and position. Planetary rovers have extremely slow speed (~1 cm/s) and lack conventional navigation sensors/systems, hence the general methods of terrestrial navigation may not be applicable to these applications. While relative attitude and position can be tracked in a way similar to those for ground robots, absolute navigation information is hard to achieve on a remote celestial body, like Moon or Mars, in contrast to terrestrial applications. In this study, two absolute attitude estimation algorithms were developed and compared for accuracy and robustness. The estimated absolute attitude was fused with the relative attitude sensors in a framework of nonlinear filters. The nonlinear Extended Kalman filter (EKF) and Unscented Kalman filter (UKF) were compared in pursuit of better accuracy and reliability in this nonlinear estimation problem, using only on-board low cost MEMS sensors. Experimental results confirmed the viability of the proposed algorithms and the sensor suite, for low cost and low weight micro planetary rovers. It is demonstrated that integrating the relative and absolute navigation MEMS sensors reduces the navigation errors to the desired level. PMID:27223293

  5. Register file soft error recovery

    DOEpatents

    Fleischer, Bruce M.; Fox, Thomas W.; Wait, Charles D.; Muff, Adam J.; Watson, III, Alfred T.

    2013-10-15

    Register file soft error recovery including a system that includes a first register file and a second register file that mirrors the first register file. The system also includes an arithmetic pipeline for receiving data read from the first register file, and error detection circuitry to detect whether the data read from the first register file includes corrupted data. The system further includes error recovery circuitry to insert an error recovery instruction into the arithmetic pipeline in response to detecting the corrupted data. The inserted error recovery instruction replaces the corrupted data in the first register file with a copy of the data from the second register file.

  6. Rapid mapping of volumetric errors

    SciTech Connect

    Krulewich, D.; Hale, L.; Yordy, D.

    1995-09-13

    This paper describes a relatively inexpensive, fast, and easy to execute approach to mapping the volumetric errors of a machine tool, coordinate measuring machine, or robot. An error map is used to characterize a machine or to improve its accuracy by compensating for the systematic errors. The method consists of three steps: (1) modeling the relationship between the volumetric error and the current state of the machine; (2) acquiring error data based on length measurements throughout the work volume; and (3) optimizing the model to the particular machine.

  7. Preliminary estimates of radiosonde thermistor errors

    NASA Technical Reports Server (NTRS)

    Schmidlin, F. J.; Luers, J. K.; Huffman, P. D.

    1986-01-01

    Radiosonde temperature measurements are subject to errors, not the least of which is the effect of long- and short-wave radiation. Methods of adjusting the daytime temperatures to a nighttime equivalent are used by some analysis centers. Other than providing consistent observations for analysis this procedure does not provide a true correction. The literature discusses the problem of radiosonde temperature errors but it is not apparent what effort, if any, has been taken to quantify these errors. To accomplish the latter, radiosondes containing multiple thermistors with different coatings were flown at Goddard Space Flight Center/Wallops Flight Facility. The coatings employed had different spectral characteristics and, therefore, different adsorption and emissivity properties. Discrimination of the recorded temperatures enabled day and night correction values to be determined for the US standard white-coated rod thermistor. The correction magnitudes are given and a comparison of US measured temperatures before and after correction are compared with temperatures measured with the Vaisala radiosonde. The corrections are in the proper direction, day and night, and reduce day-night temperature differences to less than 0.5 C between surface and 30 hPa. The present uncorrected temperatures used with the Viz radiosonde have day-night differences that exceed 1 C at levels below 90 hPa. Additional measurements are planned to confirm these preliminary results and determine the solar elevation angle effect on the corrections. The technique used to obtain the corrections may also be used to recover a true absolute value and might be considered a valuable contribution to the meteorological community for use as a reference instrument.

  8. Absolute Timing of the Crab Pulsar: X-ray, Radio, and Optical Observations

    NASA Astrophysics Data System (ADS)

    Ray, P. S.; Wood, K. S.; Wolff, M. T.; Lovellette, M. N.; Sheikh, S.; Moon, D.-S.; Eikenberry, S. S.; Roberts, M.; Bloom, E. D.; Tournear, D.; Saz Parkinson, P.; Reilly, K.

    2002-12-01

    We report on multiwavelength observations of the Crab Pulsar and compare the pulse arrival time at radio, IR, optical, and X-ray wavelengths. Comparing absolute arrival times at multiple energies can provide clues to the magnetospheric structure and emission region geometry. Absolute time calibration of each observing system is of paramount importance for these observations and we describe how this is done for each system. We directly compare arrival time determinations for 2--10 keV X-ray observations made contemporaneously with the PCA on the Rossi X-ray Timing Explorer and the USA Experiment on ARGOS. These two X-ray measurements employ very different means of measuring time and satellite position and thus have different systematic error budgets. The comparison with other wavelengths requires additional steps such as dispersion measure corrections and a precise definition of the ``peak'' of the light curve since the light curve shape varies with observing wavelength. We will describe each of these effects and quantify the magnitude of the systematic error that each may contribute. Basic research on X-ray Astronomy at NRL is funded by NRL/ONR.

  9. Social aspects of clinical errors.

    PubMed

    Richman, Joel; Mason, Tom; Mason-Whitehead, Elizabeth; McIntosh, Annette; Mercer, Dave

    2009-08-01

    Clinical errors, whether committed by doctors, nurses or other professions allied to healthcare, remain a sensitive issue requiring open debate and policy formulation in order to reduce them. The literature suggests that the issues underpinning errors made by healthcare professionals involve concerns about patient safety, professional disclosure, apology, litigation, compensation, processes of recording and policy development to enhance quality service. Anecdotally, we are aware of narratives of minor errors, which may well have been covered up and remain officially undisclosed whilst the major errors resulting in damage and death to patients alarm both professionals and public with resultant litigation and compensation. This paper attempts to unravel some of these issues by highlighting the historical nature of clinical errors and drawing parallels to contemporary times by outlining the 'compensation culture'. We then provide an overview of what constitutes a clinical error and review the healthcare professional strategies for managing such errors. PMID:19201405

  10. The 13 errors.

    PubMed

    Flower, J

    1998-01-01

    The reality is that most change efforts fail. McKinsey & Company carried out a fascinating research project on change to "crack the code" on creating and managing change in large organizations. One of the questions they asked--and answered--is why most organizations fail in their efforts to manage change. They found that 80 percent of these failures could be traced to 13 common errors. They are: (1) No winning strategy; (2) failure to make a compelling and urgent case for change; (3) failure to distinguish between decision-driven and behavior-dependent change; (4) over-reliance on structure and systems to change behavior; (5) lack of skills and resources; (6) failure to experiment; (7) leaders' inability or unwillingness to confront how they and their roles must change; (8) failure to mobilize and engage pivotal groups; (9) failure to understand and shape the informal organization; (10) inability to integrate and align all the initiatives; (11) no performance focus; (12) excessively open-ended process; and (13) failure to make the whole process transparent and meaningful to individuals. PMID:10351717

  11. Contour Error Map Algorithm

    NASA Technical Reports Server (NTRS)

    Merceret, Francis; Lane, John; Immer, Christopher; Case, Jonathan; Manobianco, John

    2005-01-01

    The contour error map (CEM) algorithm and the software that implements the algorithm are means of quantifying correlations between sets of time-varying data that are binarized and registered on spatial grids. The present version of the software is intended for use in evaluating numerical weather forecasts against observational sea-breeze data. In cases in which observational data come from off-grid stations, it is necessary to preprocess the observational data to transform them into gridded data. First, the wind direction is gridded and binarized so that D(i,j;n) is the input to CEM based on forecast data and d(i,j;n) is the input to CEM based on gridded observational data. Here, i and j are spatial indices representing 1.25-km intervals along the west-to-east and south-to-north directions, respectively; and n is a time index representing 5-minute intervals. A binary value of D or d = 0 corresponds to an offshore wind, whereas a value of D or d = 1 corresponds to an onshore wind. CEM includes two notable subalgorithms: One identifies and verifies sea-breeze boundaries; the other, which can be invoked optionally, performs an image-erosion function for the purpose of attempting to eliminate river-breeze contributions in the wind fields.

  12. Error analysis in laparoscopic surgery

    NASA Astrophysics Data System (ADS)

    Gantert, Walter A.; Tendick, Frank; Bhoyrul, Sunil; Tyrrell, Dana; Fujino, Yukio; Rangel, Shawn; Patti, Marco G.; Way, Lawrence W.

    1998-06-01

    Iatrogenic complications in laparoscopic surgery, as in any field, stem from human error. In recent years, cognitive psychologists have developed theories for understanding and analyzing human error, and the application of these principles has decreased error rates in the aviation and nuclear power industries. The purpose of this study was to apply error analysis to laparoscopic surgery and evaluate its potential for preventing complications. Our approach is based on James Reason's framework using a classification of errors according to three performance levels: at the skill- based performance level, slips are caused by attention failures, and lapses result form memory failures. Rule-based mistakes constitute the second level. Knowledge-based mistakes occur at the highest performance level and are caused by shortcomings in conscious processing. These errors committed by the performer 'at the sharp end' occur in typical situations which often times are brought about by already built-in latent system failures. We present a series of case studies in laparoscopic surgery in which errors are classified and the influence of intrinsic failures and extrinsic system flaws are evaluated. Most serious technical errors in lap surgery stem from a rule-based or knowledge- based mistake triggered by cognitive underspecification due to incomplete or illusory visual input information. Error analysis in laparoscopic surgery should be able to improve human performance, and it should detect and help eliminate system flaws. Complication rates in laparoscopic surgery due to technical errors can thus be considerably reduced.

  13. Mini-implants and miniplates generate sub-absolute and absolute anchorage

    PubMed Central

    Consolaro, Alberto

    2014-01-01

    The functional demand imposed on bone promotes changes in the spatial properties of osteocytes as well as in their extensions uniformly distributed throughout the mineralized surface. Once spatial deformation is established, osteocytes create the need for structural adaptations that result in bone formation and resorption that happen to meet the functional demands. The endosteum and the periosteum are the effectors responsible for stimulating adaptive osteocytes in the inner and outer surfaces.Changes in shape, volume and position of the jaws as a result of skeletal correction of the maxilla and mandible require anchorage to allow bone remodeling to redefine morphology, esthetics and function as a result of spatial deformation conducted by orthodontic appliances. Examining the degree of changes in shape, volume and structural relationship of areas where mini-implants and miniplates are placed allows us to classify mini-implants as devices of subabsolute anchorage and miniplates as devices of absolute anchorage. PMID:25162561

  14. Absolute brightness temperature measurements at 2.1-mm wavelength

    NASA Technical Reports Server (NTRS)

    Ulich, B. L.

    1974-01-01

    Absolute measurements of the brightness temperatures of the Sun, new Moon, Venus, Mars, Jupiter, Saturn, and Uranus, and of the flux density of DR21 at 2.1-mm wavelength are reported. Relative measurements at 3.5-mm wavelength are also preented which resolve the absolute calibration discrepancy between The University of Texas 16-ft radio telescope and the Aerospace Corporation 15-ft antenna. The use of the bright planets and DR21 as absolute calibration sources at millimeter wavelengths is discussed in the light of recent observations.

  15. Absolute Antenna Calibration at the US National Geodetic Survey

    NASA Astrophysics Data System (ADS)

    Mader, G. L.; Bilich, A. L.

    2012-12-01

    Geodetic GNSS applications routinely demand millimeter precision and extremely high levels of accuracy. To achieve these accuracies, 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 absolute calibrations - the IGS adopted absolute antenna phase center calibrations in 2006 for use in their orbit and clock products, and NGS's CORS group began using absolute 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 absolute, it is considered best practice to independently measure phase center characteristics in an absolute sense. Consequently, NGS has developed and operates an absolute calibration system. These absolute antenna calibrations accommodate the demand for greater accuracy 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

  16. Random errors in egocentric networks.

    PubMed

    Almquist, Zack W

    2012-10-01

    The systematic errors that are induced by a combination of human memory limitations and common survey design and implementation have long been studied in the context of egocentric networks. Despite this, little if any work exists in the area of random error analysis on these same networks; this paper offers a perspective on the effects of random errors on egonet analysis, as well as the effects of using egonet measures as independent predictors in linear models. We explore the effects of false-positive and false-negative error in egocentric networks on both standard network measures and on linear models through simulation analysis on a ground truth egocentric network sample based on facebook-friendships. Results show that 5-20% error rates, which are consistent with error rates known to occur in ego network data, can cause serious misestimation of network properties and regression parameters. PMID:23878412

  17. Random errors in egocentric networks

    PubMed Central

    Almquist, Zack W.

    2013-01-01

    The systematic errors that are induced by a combination of human memory limitations and common survey design and implementation have long been studied in the context of egocentric networks. Despite this, little if any work exists in the area of random error analysis on these same networks; this paper offers a perspective on the effects of random errors on egonet analysis, as well as the effects of using egonet measures as independent predictors in linear models. We explore the effects of false-positive and false-negative error in egocentric networks on both standard network measures and on linear models through simulation analysis on a ground truth egocentric network sample based on facebook-friendships. Results show that 5–20% error rates, which are consistent with error rates known to occur in ego network data, can cause serious misestimation of network properties and regression parameters. PMID:23878412

  18. Dopamine reward prediction error coding

    PubMed Central

    Schultz, Wolfram

    2016-01-01

    Reward prediction errors consist of the differences between received and predicted rewards. They are crucial for basic forms of learning about rewards and make us strive for more rewards—an evolutionary beneficial trait. Most dopamine neurons in the midbrain of humans, monkeys, and rodents signal a reward prediction error; they are activated by more reward than predicted (positive prediction error), remain at baseline activity for fully predicted rewards, and show depressed activity with less reward than predicted (negative prediction error). The dopamine signal increases nonlinearly with reward value and codes formal economic utility. Drugs of addiction generate, hijack, and amplify the dopamine reward signal and induce exaggerated, uncontrolled dopamine effects on neuronal plasticity. The striatum, amygdala, and frontal cortex also show reward prediction error coding, but only in subpopulations of neurons. Thus, the important concept of reward prediction errors is implemented in neuronal hardware. PMID:27069377

  19. Statistical errors in Monte Carlo estimates of systematic errors

    NASA Astrophysics Data System (ADS)

    Roe, Byron P.

    2007-01-01

    For estimating the effects of a number of systematic errors on a data sample, one can generate Monte Carlo (MC) runs with systematic parameters varied and examine the change in the desired observed result. Two methods are often used. In the unisim method, the systematic parameters are varied one at a time by one standard deviation, each parameter corresponding to a MC run. In the multisim method (see ), each MC run has all of the parameters varied; the amount of variation is chosen from the expected distribution of each systematic parameter, usually assumed to be a normal distribution. The variance of the overall systematic error determination is derived for each of the two methods and comparisons are made between them. If one focuses not on the error in the prediction of an individual systematic error, but on the overall error due to all systematic errors in the error matrix element in data bin m, the number of events needed is strongly reduced because of the averaging effect over all of the errors. For simple models presented here the multisim model was far better if the statistical error in the MC samples was larger than an individual systematic error, while for the reverse case, the unisim model was better. Exact formulas and formulas for the simple toy models are presented so that realistic calculations can be made. The calculations in the present note are valid if the errors are in a linear region. If that region extends sufficiently far, one can have the unisims or multisims correspond to k standard deviations instead of one. This reduces the number of events required by a factor of k2. The specific terms unisim and multisim were coined by Peter Meyers and Steve Brice, respectively, for the MiniBooNE experiment. However, the concepts have been developed over time and have been in general use for some time.

  20. Teratogenic inborn errors of metabolism.

    PubMed Central

    Leonard, J. V.

    1986-01-01

    Most children with inborn errors of metabolism are born healthy without malformations as the fetus is protected by the metabolic activity of the placenta. However, certain inborn errors of the fetus have teratogenic effects although the mechanisms responsible for the malformations are not generally understood. Inborn errors in the mother may also be teratogenic. The adverse effects of these may be reduced by improved metabolic control of the biochemical disorder. PMID:3540927

  1. An Absolute Proper motions and position catalog in the galaxy halos

    NASA Astrophysics Data System (ADS)

    Qi, Zhaoxiang

    2015-08-01

    We present a new catalog of absolute proper motions and updated positions derived from the same Space Telescope Science Institute digitized Schmidt survey plates utilized for the construction of the Guide Star Catalog II. As special attention was devoted to the absolutization process and removal of position, magnitude and color dependent systematic errors through the use of both stars and galaxies, this release is solely based on plate data outside the galactic plane, i.e. |b| ≥ 27o. The resulting global zero point error is less than 0.6 mas/yr, and the precision better than 4.0 mas/yr for objects brighter than RF = 18.5, rising to 9.0 mas/yr for objects with magnitude in the range 18.5 < RF < 20.0. The catalog covers 22,525 square degrees and lists 100,777,385 objects to the limiting magnitude of RF ˜ 20.8. Alignment with the International Celestial Reference System (ICRS) was made using 1288 objects common to the second realization of the International Celestial Reference Frame (ICRF2) at radio wavelengths. As a result, the coordinate axes realized by our astrometric data are believed to be aligned with the extragalactic radio frame to within ±0.2 mas at the reference epoch J2000.0. This makes our compilation one of the deepest and densest ICRF-registered astrometric catalogs outside the galactic plane. Although the Gaia mission is poised to set the new standard in catalog astronomy and will in many ways supersede this catalog, the methods and procedures reported here will prove useful to remove astrometric magnitude- and color-dependent systematic errors from the next generation of ground-based surveys reaching significantly deeper than the Gaia catalog.

  2. Confidence limits and their errors

    SciTech Connect

    Rajendran Raja

    2002-03-22

    Confidence limits are common place in physics analysis. Great care must be taken in their calculation and use especially in cases of limited statistics. We introduce the concept of statistical errors of confidence limits and argue that not only should limits be calculated but also their errors in order to represent the results of the analysis to the fullest. We show that comparison of two different limits from two different experiments becomes easier when their errors are also quoted. Use of errors of confidence limits will lead to abatement of the debate on which method is best suited to calculate confidence limits.

  3. Compensating For GPS Ephemeris Error

    NASA Technical Reports Server (NTRS)

    Wu, Jiun-Tsong

    1992-01-01

    Method of computing position of user station receiving signals from Global Positioning System (GPS) of navigational satellites compensates for most of GPS ephemeris error. Present method enables user station to reduce error in its computed position substantially. User station must have access to two or more reference stations at precisely known positions several hundred kilometers apart and must be in neighborhood of reference stations. Based on fact that when GPS data used to compute baseline between reference station and user station, vector error in computed baseline is proportional ephemeris error and length of baseline.

  4. Retransmission error control with memory

    NASA Technical Reports Server (NTRS)

    Sindhu, P. S.

    1977-01-01

    In this paper, an error control technique that is a basic improvement over automatic-repeat-request ARQ is presented. Erroneously received blocks in an ARQ system are used for error control. The technique is termed ARQ-with-memory (MRQ). The general MRQ system is described, and simple upper and lower bounds are derived on the throughput achievable by MRQ. The performance of MRQ with respect to throughput, message delay and probability of error is compared to that of ARQ by simulating both systems using error data from a VHF satellite channel being operated in the ALOHA packet broadcasting mode.

  5. Medication Errors in Outpatient Pediatrics.

    PubMed

    Berrier, Kyla

    2016-01-01

    Medication errors may occur during parental administration of prescription and over-the-counter medications in the outpatient pediatric setting. Misinterpretation of medication labels and dosing errors are two types of errors in medication administration. Health literacy may play an important role in parents' ability to safely manage their child's medication regimen. There are several proposed strategies for decreasing these medication administration errors, including using standardized dosing instruments, using strictly metric units for medication dosing, and providing parents and caregivers with picture-based dosing instructions. Pediatric healthcare providers should be aware of these strategies and seek to implement many of them into their practices. PMID:27537086

  6. Physical examination. Frequently observed errors.

    PubMed

    Wiener, S; Nathanson, M

    1976-08-16

    A method allowing for direct observation of intern and resident physicians while interviewing and examining patients has been in use on our medical wards for the last five years. A large number of errors in the performance of the medical examination by young physicians were noted and a classification of these errors into those of technique, omission, detection, interpretation, and recording was made. An approach to detection and correction of each of these kinds of errors is presented, as well as a discussion of possible reasons for the occurrence of these errors in physician performance. PMID:947266

  7. A theory of human error

    NASA Technical Reports Server (NTRS)

    Mcruer, D. T.; Clement, W. F.; Allen, R. W.

    1980-01-01

    Human error, a significant contributing factor in a very high proportion of civil transport, general aviation, and rotorcraft accidents is investigated. Correction of the sources of human error requires that one attempt to reconstruct underlying and contributing causes of error from the circumstantial causes cited in official investigative reports. A validated analytical theory of the input-output behavior of human operators involving manual control, communication, supervisory, and monitoring tasks which are relevant to aviation operations is presented. This theory of behavior, both appropriate and inappropriate, provides an insightful basis for investigating, classifying, and quantifying the needed cause-effect relationships governing propagation of human error.

  8. Absolute calibration of sniffer probes on Wendelstein 7-X.

    PubMed

    Moseev, D; Laqua, H P; Marsen, S; Stange, T; Braune, H; Erckmann, V; Gellert, F; Oosterbeek, J W

    2016-08-01

    Here we report the first measurements of the power levels of stray radiation in the vacuum vessel of Wendelstein 7-X using absolutely calibrated sniffer probes. The absolute calibration is achieved by using calibrated sources of stray radiation and the implicit measurement of the quality factor of the Wendelstein 7-X empty vacuum vessel. Normalized absolute calibration coefficients agree with the cross-calibration coefficients that are obtained by the direct measurements, indicating that the measured absolute calibration coefficients and stray radiation levels in the vessel are valid. Close to the launcher, the stray radiation in the empty vessel reaches power levels up to 340 kW/m(2) per MW injected beam power. Furthest away from the launcher, i.e., half a toroidal turn, still 90 kW/m(2) per MW injected beam power is measured. PMID:27587121

  9. Absolute Value Boundedness, Operator Decomposition, and Stochastic Media and Equations

    NASA Technical Reports Server (NTRS)

    Adomian, G.; Miao, C. C.

    1973-01-01

    The research accomplished during this period is reported. Published abstracts and technical reports are listed. Articles presented include: boundedness of absolute values of generalized Fourier coefficients, propagation in stochastic media, and stationary conditions for stochastic differential equations.

  10. The conditions of absolute summability of multiple trigonometric series

    NASA Astrophysics Data System (ADS)

    Bitimkhan, Samat; Akishev, Gabdolla

    2015-09-01

    In this work necessary and sufficient conditions of absolute summability of multiple trigonometric Fourier series of functions from anisotropic spaces of Lebesque are found in terms of its best approximation, the module of smoothness and the mixed smoothness module.

  11. Absolute calibration of sniffer probes on Wendelstein 7-X

    NASA Astrophysics Data System (ADS)

    Moseev, D.; Laqua, H. P.; Marsen, S.; Stange, T.; Braune, H.; Erckmann, V.; Gellert, F.; Oosterbeek, J. W.

    2016-08-01

    Here we report the first measurements of the power levels of stray radiation in the vacuum vessel of Wendelstein 7-X using absolutely calibrated sniffer probes. The absolute calibration is achieved by using calibrated sources of stray radiation and the implicit measurement of the quality factor of the Wendelstein 7-X empty vacuum vessel. Normalized absolute calibration coefficients agree with the cross-calibration coefficients that are obtained by the direct measurements, indicating that the measured absolute calibration coefficients and stray radiation levels in the vessel are valid. Close to the launcher, the stray radiation in the empty vessel reaches power levels up to 340 kW/m2 per MW injected beam power. Furthest away from the launcher, i.e., half a toroidal turn, still 90 kW/m2 per MW injected beam power is measured.

  12. On the absolute calibration of SO2 cameras

    NASA Astrophysics Data System (ADS)

    Lübcke, P.; Bobrowski, N.; Illing, S.; Kern, C.; Alvarez Nieves, J. M.; Vogel, L.; Zielcke, J.; Delgado Granados, H.; Platt, U.

    2012-09-01

    Sulphur dioxide emission flux measurements are an important tool for volcanic monitoring and eruption risk assessment. The SO2 camera technique remotely measures volcanic emissions by analysing the ultraviolet absorption of SO2 in a narrow spectral window between 305 nm and 320 nm using solar radiation scattered in the atmosphere. The SO2 absorption is selectively detected by mounting band-pass interference filters in front of a two-dimensional, UV-sensitive CCD detector. While this approach is simple and delivers valuable insights into the two-dimensional SO2 distribution, absolute calibration has proven to be difficult. An accurate calibration of the SO2 camera (i.e., conversion from optical density to SO2 column density, CD) is crucial to obtain correct SO2 CDs and flux measurements that are comparable to other measurement techniques and can be used for volcanological applications. The most common approach for calibrating SO2 camera measurements is based on inserting quartz cells (cuvettes) containing known amounts of SO2 into the light path. It has been found, however, that reflections from the windows of the calibration cell can considerably affect the signal measured by the camera. Another possibility for calibration relies on performing simultaneous measurements in a small area of the camera's field-of-view (FOV) by a narrow-field-of-view Differential Optical Absorption Spectroscopy (NFOV-DOAS) system. This procedure combines the very good spatial and temporal resolution of the SO2 camera technique with the more accurate column densities obtainable from DOAS measurements. This work investigates the uncertainty of results gained through the two commonly used, but quite different calibration methods (DOAS and calibration cells). Measurements with three different instruments, an SO2 camera, a NFOV-DOAS system and an Imaging DOAS (IDOAS), are presented. We compare the calibration-cell approach with the calibration from the NFOV-DOAS system. The respective

  13. A posteriori error estimator and error control for contact problems

    NASA Astrophysics Data System (ADS)

    Weiss, Alexander; Wohlmuth, Barbara I.

    2009-09-01

    In this paper, we consider two error estimators for one-body contact problems. The first error estimator is defined in terms of H( div ) -conforming stress approximations and equilibrated fluxes while the second is a standard edge-based residual error estimator without any modification with respect to the contact. We show reliability and efficiency for both estimators. Moreover, the error is bounded by the first estimator with a constant one plus a higher order data oscillation term plus a term arising from the contact that is shown numerically to be of higher order. The second estimator is used in a control-based AFEM refinement strategy, and the decay of the error in the energy is shown. Several numerical tests demonstrate the performance of both estimators.

  14. Absolute and Convective Instability of a Liquid Jet in Microgravity

    NASA Technical Reports Server (NTRS)

    Lin, Sung P.; Vihinen, I.; Honohan, A.; Hudman, Michael D.

    1996-01-01

    The transition from convective to absolute instability is observed in the 2.2 second drop tower of the NASA Lewis Research Center. In convective instability the disturbance grows spatially as it is convected downstream. In absolute instability the disturbance propagates both downstream and upstream, and manifests itself as an expanding sphere. The transition Reynolds numbers are determined for two different Weber numbers by use of Glycerin and a Silicone oil. Preliminary comparisons with theory are made.

  15. Absolute biphoton meter of the quantum efficiency of photomultipliers

    NASA Astrophysics Data System (ADS)

    Ginzburg, V. M.; Keratishvili, N. G.; Korzhenevich, E. L.; Lunev, G. V.; Sapritskii, V. I.

    1992-07-01

    An biphoton absolute meter of photomultiplier quantum efficiency is presented which is based on spontaneous parametric down-conversion. Calculation and experiment results were obtained which made it possible to choose the parameters of the setup that guarantee a linear dependence of wavelength on the Z coordinate (along the axicon axis). Results of a series of absolute measurements of the quantum efficiency of a specific photomultiplier (FEU-136) are presented.

  16. Absolute/convective instability of planar viscoelastic jets

    NASA Astrophysics Data System (ADS)

    Ray, Prasun K.; Zaki, Tamer A.

    2015-01-01

    Spatiotemporal linear stability analysis is used to investigate the onset of local absolute instability in planar viscoelastic jets. The influence of viscoelasticity in dilute polymer solutions is modeled with the FENE-P constitutive equation which requires the specification of a non-dimensional polymer relaxation time (the Weissenberg number, We), the maximum polymer extensibility, L, and the ratio of solvent and solution viscosities, β. A two-parameter family of velocity profiles is used as the base state with the parameter, S, controlling the amount of co- or counter-flow while N-1 sets the thickness of the jet shear layer. We examine how the variation of these fluid and flow parameters affects the minimum value of S at which the flow becomes locally absolutely unstable. Initially setting the Reynolds number to Re = 500, we find that the first varicose jet-column mode dictates the presence of absolute instability, and increasing the Weissenberg number produces important changes in the nature of the instability. The region of absolute instability shifts towards thin shear layers, and the amount of back-flow needed for absolute instability decreases (i.e., the influence of viscoelasticity is destabilizing). Additionally, when We is sufficiently large and N-1 is sufficiently small, single-stream jets become absolutely unstable. Numerical experiments with approximate equations show that both the polymer and solvent contributions to the stress become destabilizing when the scaled shear rate, η = /W e dU¯1/dx 2L ( /d U ¯ 1 d x 2 is the base-state velocity gradient), is sufficiently large. These qualitative trends are largely unchanged when the Reynolds number is reduced; however, the relative importance of the destabilizing stresses increases tangibly. Consequently, absolute instability is substantially enhanced, and single-stream jets become absolutely unstable over a sizable portion of the parameter space.

  17. Heat capacity and absolute entropy of iron phosphides

    SciTech Connect

    Dobrokhotova, Z.V.; Zaitsev, A.I.; Litvina, A.D.

    1994-09-01

    There is little or no data on the thermodynamic properties of iron phosphides despite their importance for several areas of science and technology. The information available is of a qualitative character and is based on assessments of the heat capacity and absolute entropy. In the present work, we measured the heat capacity over the temperature range of 113-873 K using a differential scanning calorimeter (DSC) and calculated the absolute entropy.

  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. Revisiting absolute and relative judgments in the WITNESS model.

    PubMed

    Fife, Dustin; Perry, Colton; Gronlund, Scott D

    2014-04-01

    The WITNESS model (Clark in Applied Cognitive Psychology 17:629-654, 2003) provides a theoretical framework with which to investigate the factors that contribute to eyewitness identification decisions. One key factor involves the contributions of absolute versus relative judgments. An absolute contribution is determined by the degree of match between an individual lineup member and memory for the perpetrator; a relative contribution involves the degree to which the best-matching lineup member is a better match to memory than the remaining lineup members. In WITNESS, the proportional contributions of relative versus absolute judgments are governed by the values of the decision weight parameters. We conducted an exploration of the WITNESS model's parameter space to determine the identifiability of these relative/absolute decision weight parameters, and compared the results to a restricted version of the model that does not vary the decision weight parameters. This exploration revealed that the decision weights in WITNESS are difficult to identify: Data often can be fit equally well by setting the decision weights to nearly any value and compensating with a criterion adjustment. Clark, Erickson, and Breneman (Law and Human Behavior 35:364-380, 2011) claimed to demonstrate a theoretical basis for the superiority of lineup decisions that are based on absolute contributions, but the relationship between the decision weights and the criterion weakens this claim. These findings necessitate reconsidering the role of the relative/absolute judgment distinction in eyewitness decision making. PMID:23943556

  20. Spatial frequency domain error budget

    SciTech Connect

    Hauschildt, H; Krulewich, D

    1998-08-27

    The aim of this paper is to describe a methodology for designing and characterizing machines used to manufacture or inspect parts with spatial-frequency-based specifications. At Lawrence Livermore National Laboratory, one of our responsibilities is to design or select the appropriate machine tools to produce advanced optical and weapons systems. Recently, many of the component tolerances for these systems have been specified in terms of the spatial frequency content of residual errors on the surface. We typically use an error budget as a sensitivity analysis tool to ensure that the parts manufactured by a machine will meet the specified component tolerances. Error budgets provide the formalism whereby we account for all sources of uncertainty in a process, and sum them to arrive at a net prediction of how "precisely" a manufactured component can meet a target specification. Using the error budget, we are able to minimize risk during initial stages by ensuring that the machine will produce components that meet specifications before the machine is actually built or purchased. However, the current error budgeting procedure provides no formal mechanism for designing machines that can produce parts with spatial-frequency-based specifications. The output from the current error budgeting procedure is a single number estimating the net worst case or RMS error on the work piece. This procedure has limited ability to differentiate between low spatial frequency form errors versus high frequency surface finish errors. Therefore the current error budgeting procedure can lead us to reject a machine that is adequate or accept a machine that is inadequate. This paper will describe a new error budgeting methodology to aid in the design and characterization of machines used to manufacture or inspect parts with spatial-frequency-based specifications. The output from this new procedure is the continuous spatial frequency content of errors that result on a machined part. If the machine

  1. Error coding simulations in C

    NASA Technical Reports Server (NTRS)

    Noble, Viveca K.

    1994-01-01

    When data is transmitted through a noisy channel, errors are produced within the data rendering it indecipherable. Through the use of error control coding techniques, the bit error rate can be reduced to any desired level without sacrificing the transmission data rate. The Astrionics Laboratory at Marshall Space Flight Center has decided to use a modular, end-to-end telemetry data simulator to simulate the transmission of data from flight to ground and various methods of error control. The simulator includes modules for random data generation, data compression, Consultative Committee for Space Data Systems (CCSDS) transfer frame formation, error correction/detection, error generation and error statistics. The simulator utilizes a concatenated coding scheme which includes CCSDS standard (255,223) Reed-Solomon (RS) code over GF(2(exp 8)) with interleave depth of 5 as the outermost code, (7, 1/2) convolutional code as an inner code and CCSDS recommended (n, n-16) cyclic redundancy check (CRC) code as the innermost code, where n is the number of information bits plus 16 parity bits. The received signal-to-noise for a desired bit error rate is greatly reduced through the use of forward error correction techniques. Even greater coding gain is provided through the use of a concatenated coding scheme. Interleaving/deinterleaving is necessary to randomize burst errors which may appear at the input of the RS decoder. The burst correction capability length is increased in proportion to the interleave depth. The modular nature of the simulator allows for inclusion or exclusion of modules as needed. This paper describes the development and operation of the simulator, the verification of a C-language Reed-Solomon code, and the possibility of using Comdisco SPW(tm) as a tool for determining optimal error control schemes.

  2. Error coding simulations in C

    NASA Astrophysics Data System (ADS)

    Noble, Viveca K.

    1994-10-01

    When data is transmitted through a noisy channel, errors are produced within the data rendering it indecipherable. Through the use of error control coding techniques, the bit error rate can be reduced to any desired level without sacrificing the transmission data rate. The Astrionics Laboratory at Marshall Space Flight Center has decided to use a modular, end-to-end telemetry data simulator to simulate the transmission of data from flight to ground and various methods of error control. The simulator includes modules for random data generation, data compression, Consultative Committee for Space Data Systems (CCSDS) transfer frame formation, error correction/detection, error generation and error statistics. The simulator utilizes a concatenated coding scheme which includes CCSDS standard (255,223) Reed-Solomon (RS) code over GF(2(exp 8)) with interleave depth of 5 as the outermost code, (7, 1/2) convolutional code as an inner code and CCSDS recommended (n, n-16) cyclic redundancy check (CRC) code as the innermost code, where n is the number of information bits plus 16 parity bits. The received signal-to-noise for a desired bit error rate is greatly reduced through the use of forward error correction techniques. Even greater coding gain is provided through the use of a concatenated coding scheme. Interleaving/deinterleaving is necessary to randomize burst errors which may appear at the input of the RS decoder. The burst correction capability length is increased in proportion to the interleave depth. The modular nature of the simulator allows for inclusion or exclusion of modules as needed. This paper describes the development and operation of the simulator, the verification of a C-language Reed-Solomon code, and the possibility of using Comdisco SPW(tm) as a tool for determining optimal error control schemes.

  3. Explaining Errors in Children's Questions

    ERIC Educational Resources Information Center

    Rowland, Caroline F.

    2007-01-01

    The ability to explain the occurrence of errors in children's speech is an essential component of successful theories of language acquisition. The present study tested some generativist and constructivist predictions about error on the questions produced by ten English-learning children between 2 and 5 years of age. The analyses demonstrated that,…

  4. Dyslexia and Oral Reading Errors

    ERIC Educational Resources Information Center

    Singleton, Chris

    2005-01-01

    Thomson was the first of very few researchers to have studied oral reading errors as a means of addressing the question: Are dyslexic readers different to other readers? Using the Neale Analysis of Reading Ability and Goodman's taxonomy of oral reading errors, Thomson concluded that dyslexic readers are different, but he found that they do not…

  5. Children's Scale Errors with Tools

    ERIC Educational Resources Information Center

    Casler, Krista; Eshleman, Angelica; Greene, Kimberly; Terziyan, Treysi

    2011-01-01

    Children sometimes make "scale errors," attempting to interact with tiny object replicas as though they were full size. Here, we demonstrate that instrumental tools provide special insight into the origins of scale errors and, moreover, into the broader nature of children's purpose-guided reasoning and behavior with objects. In Study 1, 1.5- to…

  6. Robustness and modeling error characterization

    NASA Technical Reports Server (NTRS)

    Lehtomaki, N. A.; Castanon, D. A.; Sandell, N. R., Jr.; Levy, B. C.; Athans, M.; Stein, G.

    1984-01-01

    The results on robustness theory presented here are extensions of those given in Lehtomaki et al., (1981). The basic innovation in these new results is that they utilize minimal additional information about the structure of the modeling error, as well as its magnitude, to assess the robustness of feedback systems for which robustness tests based on the magnitude of modeling error alone are inconclusive.

  7. Human Error: A Concept Analysis

    NASA Technical Reports Server (NTRS)

    Hansen, Frederick D.

    2007-01-01

    Human error is the subject of research in almost every industry and profession of our times. This term is part of our daily language and intuitively understood by most people however, it would be premature to assume that everyone's understanding of human error s the same. For example, human error is used to describe the outcome or consequence of human action, the causal factor of an accident, deliberate violations,a nd the actual action taken by a human being. As a result, researchers rarely agree on the either a specific definition or how to prevent human error. The purpose of this article is to explore the specific concept of human error using Concept Analysis as described by Walker and Avant (1995). The concept of human error is examined as currently used in the literature of a variety of industries and professions. Defining attributes and examples of model, borderline, and contrary cases are described. The antecedents and consequences of human error are also discussed and a definition of human error is offered.

  8. Dual Processing and Diagnostic Errors

    ERIC Educational Resources Information Center

    Norman, Geoff

    2009-01-01

    In this paper, I review evidence from two theories in psychology relevant to diagnosis and diagnostic errors. "Dual Process" theories of thinking, frequently mentioned with respect to diagnostic error, propose that categorization decisions can be made with either a fast, unconscious, contextual process called System 1 or a slow, analytical,…

  9. Measurement Errors in Organizational Surveys.

    ERIC Educational Resources Information Center

    Dutka, Solomon; Frankel, Lester R.

    1993-01-01

    Describes three classes of measurement techniques: (1) interviewing methods; (2) record retrieval procedures; and (3) observation methods. Discusses primary reasons for measurement error. Concludes that, although measurement error can be defined and controlled for, there are other design factors that also must be considered. (CFR)

  10. Barriers to Medical Error Reporting

    PubMed Central

    Poorolajal, Jalal; Rezaie, Shirin; Aghighi, Negar

    2015-01-01

    Background: This study was conducted to explore the prevalence of medical error underreporting and associated barriers. Methods: This cross-sectional study was performed from September to December 2012. Five hospitals, affiliated with Hamadan University of Medical Sciences, in Hamedan, Iran were investigated. A self-administered questionnaire was used for data collection. Participants consisted of physicians, nurses, midwives, residents, interns, and staffs of radiology and laboratory departments. Results: Overall, 50.26% of subjects had committed but not reported medical errors. The main reasons mentioned for underreporting were lack of effective medical error reporting system (60.0%), lack of proper reporting form (51.8%), lack of peer supporting a person who has committed an error (56.0%), and lack of personal attention to the importance of medical errors (62.9%). The rate of committing medical errors was higher in men (71.4%), age of 50–40 years (67.6%), less-experienced personnel (58.7%), educational level of MSc (87.5%), and staff of radiology department (88.9%). Conclusions: This study outlined the main barriers to reporting medical errors and associated factors that may be helpful for healthcare organizations in improving medical error reporting as an essential component for patient safety enhancement. PMID:26605018

  11. Operational Interventions to Maintenance Error

    NASA Technical Reports Server (NTRS)

    Kanki, Barbara G.; Walter, Diane; Dulchinos, VIcki

    1997-01-01

    A significant proportion of aviation accidents and incidents are known to be tied to human error. However, research of flight operational errors has shown that so-called pilot error often involves a variety of human factors issues and not a simple lack of individual technical skills. In aircraft maintenance operations, there is similar concern that maintenance errors which may lead to incidents and accidents are related to a large variety of human factors issues. Although maintenance error data and research are limited, industry initiatives involving human factors training in maintenance have become increasingly accepted as one type of maintenance error intervention. Conscientious efforts have been made in re-inventing the team7 concept for maintenance operations and in tailoring programs to fit the needs of technical opeRAtions. Nevertheless, there remains a dual challenge: 1) to develop human factors interventions which are directly supported by reliable human error data, and 2) to integrate human factors concepts into the procedures and practices of everyday technical tasks. In this paper, we describe several varieties of human factors interventions and focus on two specific alternatives which target problems related to procedures and practices; namely, 1) structured on-the-job training and 2) procedure re-design. We hope to demonstrate that the key to leveraging the impact of these solutions comes from focused interventions; that is, interventions which are derived from a clear understanding of specific maintenance errors, their operational context and human factors components.

  12. Reducing latent errors, drift errors, and stakeholder dissonance.

    PubMed

    Samaras, George M

    2012-01-01

    Healthcare information technology (HIT) is being offered as a transformer of modern healthcare delivery systems. Some believe that it has the potential to improve patient safety, increase the effectiveness of healthcare delivery, and generate significant cost savings. In other industrial sectors, information technology has dramatically influenced quality and profitability - sometimes for the better and sometimes not. Quality improvement efforts in healthcare delivery have not yet produced the dramatic results obtained in other industrial sectors. This may be that previously successful quality improvement experts do not possess the requisite domain knowledge (clinical experience and expertise). It also appears related to a continuing misconception regarding the origins and meaning of work errors in healthcare delivery. The focus here is on system use errors rather than individual user errors. System use errors originate in both the development and the deployment of technology. Not recognizing stakeholders and their conflicting needs, wants, and desires (NWDs) may lead to stakeholder dissonance. Mistakes translating stakeholder NWDs into development or deployment requirements may lead to latent errors. Mistakes translating requirements into specifications may lead to drift errors. At the sharp end, workers encounter system use errors or, recognizing the risk, expend extensive and unanticipated resources to avoid them. PMID:22317001

  13. A theory of human error

    NASA Technical Reports Server (NTRS)

    Mcruer, D. T.; Clement, W. F.; Allen, R. W.

    1981-01-01

    Human errors tend to be treated in terms of clinical and anecdotal descriptions, from which remedial measures are difficult to derive. Correction of the sources of human error requires an attempt to reconstruct underlying and contributing causes of error from the circumstantial causes cited in official investigative reports. A comprehensive analytical theory of the cause-effect relationships governing propagation of human error is indispensable to a reconstruction of the underlying and contributing causes. A validated analytical theory of the input-output behavior of human operators involving manual control, communication, supervisory, and monitoring tasks which are relevant to aviation, maritime, automotive, and process control operations is highlighted. This theory of behavior, both appropriate and inappropriate, provides an insightful basis for investigating, classifying, and quantifying the needed cause-effect relationships governing propagation of human error.

  14. Onorbit IMU alignment error budget

    NASA Technical Reports Server (NTRS)

    Corson, R. W.

    1980-01-01

    The Star Tracker, Crew Optical Alignment Sight (COAS), and Inertial Measurement Unit (IMU) from a complex navigation system with a multitude of error sources were combined. A complete list of the system errors is presented. The errors were combined in a rational way to yield an estimate of the IMU alignment accuracy for STS-1. The expected standard deviation in the IMU alignment error for STS-1 type alignments was determined to be 72 arc seconds per axis for star tracker alignments and 188 arc seconds per axis for COAS alignments. These estimates are based on current knowledge of the star tracker, COAS, IMU, and navigation base error specifications, and were partially verified by preliminary Monte Carlo analysis.

  15. [In-flight absolute radiometric calibration of UAV hyperspectral camera and its validation analysis].

    PubMed

    Gou, Zhi-yang; Yan, Lei; Chen, Wei; Jing, Xin; Yin, Zhong-yi; Duan, Yi-ni

    2012-02-01

    With the data in Urad Front Banner, Inner Mongolia on November 14th, 2010, hyper-spectral camera on UAV was calibrated adopting reflectance-based method. During the in-flight absolute radiometric calibration, 6 hyper-spectral radiometric gray-scale targets were arranged in the validation field. These targets' reflectances are 4.5%, 20%, 30%, 40%, 50% and 60% separately. To validate the calibration result, four extra hyper-spectral targets with sharp-edge spectrum were arranged to simulate the reflection and absorption peaks in natural objectives. With these peaks, the apparent radiance calculated by radiation transfer model and that calculated through calibration coefficients are much different. The result shows that in the first 15 bands (blue bands), errors are somewhat huge due to the noises of equipment. In the rest bands with quite even spectrum, the errors are small, most of which are less than 10%. For those bands with sharp changes in spectral curves, the errors are quite considerable, varying from 10% to 25%. PMID:22512184

  16. Error Analysis of non-TLD HDR Brachytherapy Dosimetric Techniques

    NASA Astrophysics Data System (ADS)

    Amoush, Ahmad

    The American Association of Physicists in Medicine Task Group Report43 (AAPM-TG43) and its updated version TG-43U1 rely on the LiF TLD detector to determine the experimental absolute dose rate for brachytherapy. The recommended uncertainty estimates associated with TLD experimental dosimetry include 5% for statistical errors (Type A) and 7% for systematic errors (Type B). TG-43U1 protocol does not include recommendation for other experimental dosimetric techniques to calculate the absolute dose for brachytherapy. This research used two independent experimental methods and Monte Carlo simulations to investigate and analyze uncertainties and errors associated with absolute dosimetry of HDR brachytherapy for a Tandem applicator. An A16 MicroChamber* and one dose MOSFET detectors† were selected to meet the TG-43U1 recommendations for experimental dosimetry. Statistical and systematic uncertainty analyses associated with each experimental technique were analyzed quantitatively using MCNPX 2.6‡ to evaluate source positional error, Tandem positional error, the source spectrum, phantom size effect, reproducibility, temperature and pressure effects, volume averaging, stem and wall effects, and Tandem effect. Absolute dose calculations for clinical use are based on Treatment Planning System (TPS) with no corrections for the above uncertainties. Absolute dose and uncertainties along the transverse plane were predicted for the A16 microchamber. The generated overall uncertainties are 22%, 17%, 15%, 15%, 16%, 17%, and 19% at 1cm, 2cm, 3cm, 4cm, and 5cm, respectively. Predicting the dose beyond 5cm is complicated due to low signal-to-noise ratio, cable effect, and stem effect for the A16 microchamber. Since dose beyond 5cm adds no clinical information, it has been ignored in this study. The absolute dose was predicted for the MOSFET detector from 1cm to 7cm along the transverse plane. The generated overall uncertainties are 23%, 11%, 8%, 7%, 7%, 9%, and 8% at 1cm, 2cm, 3cm

  17. Test Plan for a Calibration Demonstration System for the Reflected Solar Instrument for the Climate Absolute Radiance and Refractivity Observatory

    NASA Technical Reports Server (NTRS)

    Thome, Kurtis; McCorkel, Joel; Hair, Jason; McAndrew, Brendan; Daw, Adrian; Jennings, Donald; Rabin, Douglas

    2012-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission addresses the need to observe high-accuracy, long-term climate change trends and to use decadal change observations as the most critical method to determine the accuracy of climate change. One of the major objectives of CLARREO is to advance the accuracy of SI traceable absolute calibration at infrared and reflected solar wavelengths. This advance is required to reach the on-orbit absolute accuracy required to allow climate change observations to survive data gaps while remaining sufficiently accurate to observe climate change to within the uncertainty of the limit of natural variability. While these capabilities exist at NIST in the laboratory, there is a need to demonstrate that it can move successfully from NIST to NASA and/or instrument vendor capabilities for future spaceborne instruments. The current work describes the test plan for the Solar, Lunar for Absolute 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 end result of efforts with the SOLARIS CDS will be an SI-traceable error budget for reflectance retrieval using solar irradiance as a reference and methods for laboratory-based, absolute calibration suitable for climate-quality data collections. The CLARREO mission addresses the need to observe high-accuracy, long-term climate change trends and advance the accuracy of SI traceable absolute calibration. The current work describes the test plan for the SOLARIS which is the calibration demonstration

  18. Instrumentation and First Results of the Reflected Solar Demonstration System for the Climate Absolute Radiance and Refractivity Observatory

    NASA Technical Reports Server (NTRS)

    McCorkel, Joel; Thome, Kurtis; Hair, Jason; McAndrew, Brendan; Jennings, Don; Rabin, Douglas; Daw, Adrian; Lundsford, Allen

    2012-01-01

    The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission key goals include enabling observation of high accuracy long-term climate change trends, use of these observations to test and improve climate forecasts, and calibration of operational and research sensors. The spaceborne instrument suites include a reflected solar spectroradiometer, emitted infrared spectroradiometer, and radio occultation receivers. The requirement for the RS instrument is that derived reflectance must be traceable to Sl standards with an absolute uncertainty of <0.3% and the error budget that achieves this requirement is described in previo1L5 work. This work describes the Solar/Lunar Absolute Reflectance Imaging Spectroradiometer (SOLARIS), a calibration demonstration system for RS instrument, and presents initial calibration and characterization methods and results. SOLARIS is an Offner spectrometer with two separate focal planes each with its own entrance aperture and grating covering spectral ranges of 320-640, 600-2300 nm over a full field-of-view of 10 degrees with 0.27 milliradian sampling. Results from laboratory measurements including use of integrating spheres, transfer radiometers and spectral standards combined with field-based solar and lunar acquisitions are presented. These results will be used to assess the accuracy and repeatability of the radiometric and spectral characteristics of SOLARIS, which will be presented against the sensor-level requirements addressed in the CLARREO RS instrument error budget.

  19. Error diffusion with a more symmetric error distribution

    NASA Astrophysics Data System (ADS)

    Fan, Zhigang

    1994-05-01

    In this paper a new error diffusion algorithm is presented that effectively eliminates the `worm' artifacts appearing in the standard methods. The new algorithm processes each scanline of the image in two passes, a forward pass followed by a backward one. This enables the error made at one pixel to be propagated to all the `future' pixels. A much more symmetric error distribution is achieved than that of the standard methods. The frequency response of the noise shaping filter associated with the new algorithm is mirror-symmetric in magnitude.

  20. Error bounds for MEG and EEG source localization

    SciTech Connect

    Mosher, J.C. . Signal and Image Processing Inst. Los Alamos National Lab., NM ); Spencer, M.E. . Signal and Image Processing Inst. TRW Space and Defense, One Space Park, Redondo Beach, CA ); Leahy, R.M. (University of Southern Californ

    1992-01-01

    Localization error bounds are presented for both EEG and MEG as graphical error contours for a 37 sensor arrangement. Both one and two dipole cases were examined for all possible dipole orientations and locations within a head quadrant. The results show a strong dependence on absolute dipole location and orientation. The results also show that fusion of the EEG and MEG measurements into a combined model reduces the lower bound. A Monte-Carlo simulation was performed to check the tightness of the bounds for a selected case. The simple head model, the white and relatively low power noise, and the few relatively strong dipoles were all selected in this study as optimistic conditions to establish possibly fundamental resolution limits for any localization effort.

  1. Error bounds for MEG and EEG source localization

    SciTech Connect

    Mosher, J.C. |; Spencer, M.E. |; Leahy, R.M.; Lewis, P.S.

    1992-12-01

    Localization error bounds are presented for both EEG and MEG as graphical error contours for a 37 sensor arrangement. Both one and two dipole cases were examined for all possible dipole orientations and locations within a head quadrant. The results show a strong dependence on absolute dipole location and orientation. The results also show that fusion of the EEG and MEG measurements into a combined model reduces the lower bound. A Monte-Carlo simulation was performed to check the tightness of the bounds for a selected case. The simple head model, the white and relatively low power noise, and the few relatively strong dipoles were all selected in this study as optimistic conditions to establish possibly fundamental resolution limits for any localization effort.

  2. Error and objectivity: cognitive illusions and qualitative research.

    PubMed

    Paley, John

    2005-07-01

    Psychological research has shown that cognitive illusions, of which visual illusions are just a special case, are systematic and pervasive, raising epistemological questions about how error in all forms of research can be identified and eliminated. The quantitative sciences make use of statistical techniques for this purpose, but it is not clear what the qualitative equivalent is, particularly in view of widespread scepticism about validity and objectivity. I argue that, in the light of cognitive psychology, the 'error question' cannot be dismissed as a positivist obsession, and that the concepts of truth and objectivity are unavoidable. However, they constitute only a 'minimal realism', which does not necessarily bring a commitment to 'absolute' truth, certainty, correspondence, causation, reductionism, or universal laws in its wake. The assumption that it does reflects a misreading of positivism and, ironically, precipitates a 'crisis of legitimation and representation', as described by constructivist authors. PMID:15935085

  3. Error bounds on complex floating-point multiplication

    NASA Astrophysics Data System (ADS)

    Brent, Richard; Percival, Colin; Zimmermann, Paul

    2007-09-01

    Given floating-point arithmetic with t -digit base- beta significands in which all arithmetic operations are performed as if calculated to infinite precision and rounded to a nearest representable value, we prove that the product of complex values z_0 and z_1 can be computed with maximum absolute error \\vert z_0Vert z_1\\vert frac{1}{2} beta^{1 - t} sqrt{5} . In particular, this provides relative error bounds of 2^{-24} sqrt{5} and 2^{-53} sqrt{5} for IEEE 754 single and double precision arithmetic respectively, provided that overflow, underflow, and denormals do not occur. We also provide the numerical worst cases for IEEE 754 single and double precision arithmetic.

  4. Optimal design of the absolute positioning sensor for a high-speed maglev train and research on its fault diagnosis.

    PubMed

    Zhang, Dapeng; Long, Zhiqiang; Xue, Song; Zhang, Junge

    2012-01-01

    This paper studies an absolute positioning sensor for a high-speed maglev train and its fault diagnosis method. The absolute positioning sensor is an important sensor for the high-speed maglev train to accomplish its synchronous traction. It is used to calibrate the error of the relative positioning sensor which is used to provide the magnetic phase signal. On the basis of the analysis for the principle of the absolute positioning sensor, the paper describes the design of the sending and receiving coils and realizes the hardware and the software for the sensor. In order to enhance the reliability of the sensor, a support vector machine is used to recognize the fault characters, and the signal flow method is used to locate the faulty parts. The diagnosis information not only can be sent to an upper center control computer to evaluate the reliability of the sensors, but also can realize on-line diagnosis for debugging and the quick detection when the maglev train is off-line. The absolute positioning sensor we study has been used in the actual project. PMID:23112619

  5. Optimal Design of the Absolute Positioning Sensor for a High-Speed Maglev Train and Research on Its Fault Diagnosis

    PubMed Central

    Zhang, Dapeng; Long, Zhiqiang; Xue, Song; Zhang, Junge

    2012-01-01

    This paper studies an absolute positioning sensor for a high-speed maglev train and its fault diagnosis method. The absolute positioning sensor is an important sensor for the high-speed maglev train to accomplish its synchronous traction. It is used to calibrate the error of the relative positioning sensor which is used to provide the magnetic phase signal. On the basis of the analysis for the principle of the absolute positioning sensor, the paper describes the design of the sending and receiving coils and realizes the hardware and the software for the sensor. In order to enhance the reliability of the sensor, a support vector machine is used to recognize the fault characters, and the signal flow method is used to locate the faulty parts. The diagnosis information not only can be sent to an upper center control computer to evaluate the reliability of the sensors, but also can realize on-line diagnosis for debugging and the quick detection when the maglev train is off-line. The absolute positioning sensor we study has been used in the actual project. PMID:23112619

  6. Quantum rms error and Heisenberg's error-disturbance relation

    NASA Astrophysics Data System (ADS)

    Busch, Paul

    2014-09-01

    Reports on experiments recently performed in Vienna [Erhard et al, Nature Phys. 8, 185 (2012)] and Toronto [Rozema et al, Phys. Rev. Lett. 109, 100404 (2012)] include claims of a violation of Heisenberg's error-disturbance relation. In contrast, a Heisenberg-type tradeoff relation for joint measurements of position and momentum has been formulated and proven in [Phys. Rev. Lett. 111, 160405 (2013)]. Here I show how the apparent conflict is resolved by a careful consideration of the quantum generalization of the notion of root-mean-square error. The claim of a violation of Heisenberg's principle is untenable as it is based on a historically wrong attribution of an incorrect relation to Heisenberg, which is in fact trivially violated. We review a new general trade-off relation for the necessary errors in approximate joint measurements of incompatible qubit observables that is in the spirit of Heisenberg's intuitions. The experiments mentioned may directly be used to test this new error inequality.

  7. Error compensation for thermally induced errors on a machine tool

    SciTech Connect

    Krulewich, D.A.

    1996-11-08

    Heat flow from internal and external sources and the environment create machine deformations, resulting in positioning errors between the tool and workpiece. There is no industrially accepted method for thermal error compensation. A simple model has been selected that linearly relates discrete temperature measurements to the deflection. The biggest problem is how to locate the temperature sensors and to determine the number of required temperature sensors. This research develops a method to determine the number and location of temperature measurements.

  8. Errors, error detection, error correction and hippocampal-region damage: data and theories.

    PubMed

    MacKay, Donald G; Johnson, Laura W

    2013-11-01

    This review and perspective article outlines 15 observational constraints on theories of errors, error detection, and error correction, and their relation to hippocampal-region (HR) damage. The core observations come from 10 studies with H.M., an amnesic with cerebellar and HR damage but virtually no neocortical damage. Three studies examined the detection of errors planted in visual scenes (e.g., a bird flying in a fish bowl in a school classroom) and sentences (e.g., I helped themselves to the birthday cake). In all three experiments, H.M. detected reliably fewer errors than carefully matched memory-normal controls. Other studies examined the detection and correction of self-produced errors, with controls for comprehension of the instructions, impaired visual acuity, temporal factors, motoric slowing, forgetting, excessive memory load, lack of motivation, and deficits in visual scanning or attention. In these studies, H.M. corrected reliably fewer errors than memory-normal and cerebellar controls, and his uncorrected errors in speech, object naming, and reading aloud exhibited two consistent features: omission and anomaly. For example, in sentence production tasks, H.M. omitted one or more words in uncorrected encoding errors that rendered his sentences anomalous (incoherent, incomplete, or ungrammatical) reliably more often than controls. Besides explaining these core findings, the theoretical principles discussed here explain H.M.'s retrograde amnesia for once familiar episodic and semantic information; his anterograde amnesia for novel information; his deficits in visual cognition, sentence comprehension, sentence production, sentence reading, and object naming; and effects of aging on his ability to read isolated low frequency words aloud. These theoretical principles also explain a wide range of other data on error detection and correction and generate new predictions for future test. PMID:23999403

  9. Absolute irradiance of the Moon for on-orbit calibration

    USGS Publications Warehouse

    Stone, T.C.; Kieffer, H.H.

    2002-01-01

    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 absolute 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 absolute radiance, then integrated to irradiance. The band-coupled extinction algorithm uses absorption spectra of several gases and aerosols derived from MODTRAN to fit time-dependent component abundances to nightly observations of standard stars. The absolute 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 absolute 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 absolute scale for lunar irradiance.

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

    NASA Astrophysics Data System (ADS)

    LHCb Collaboration

    2012-01-01

    Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. Using data taken in 2010, LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic ``van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overal precision of 3.5% in the absolute luminosity determination is reached. The techniques used to transport the absolute luminosity calibration to the full 2010 data-taking period are presented.

  11. Stochastic Models of Human Errors

    NASA Technical Reports Server (NTRS)

    Elshamy, Maged; Elliott, Dawn M. (Technical Monitor)

    2002-01-01

    Humans play an important role in the overall reliability of engineering systems. More often accidents and systems failure are traced to human errors. Therefore, in order to have meaningful system risk analysis, the reliability of the human element must be taken into consideration. Describing the human error process by mathematical models is a key to analyzing contributing factors. Therefore, the objective of this research effort is to establish stochastic models substantiated by sound theoretic foundation to address the occurrence of human errors in the processing of the space shuttle.

  12. Estimation of absolute protein quantities of unlabeled samples by selected reaction monitoring mass spectrometry.

    PubMed

    Ludwig, Christina; Claassen, Manfred; Schmidt, Alexander; Aebersold, Ruedi

    2012-03-01

    For many research questions in modern molecular and systems biology, information about absolute protein quantities is imperative. This information includes, for example, kinetic modeling of processes, protein turnover determinations, stoichiometric investigations of protein complexes, or quantitative comparisons of different proteins within one sample or across samples. To date, the vast majority of proteomic studies are limited to providing relative quantitative comparisons of protein levels between limited numbers of samples. Here we describe and demonstrate the utility of a targeting MS technique for the estimation of absolute protein abundance in unlabeled and nonfractionated cell lysates. The method is based on selected reaction monitoring (SRM) mass spectrometry and the "best flyer" hypothesis, which assumes that the specific MS signal intensity of the most intense tryptic peptides per protein is approximately constant throughout a whole proteome. SRM-targeted best flyer peptides were selected for each protein from the peptide precursor ion signal intensities from directed MS data. The most intense transitions per peptide were selected from full MS/MS scans of crude synthetic analogs. We used Monte Carlo cross-validation to systematically investigate the accuracy of the technique as a function of the number of measured best flyer peptides and the number of SRM transitions per peptide. We found that a linear model based on the two most intense transitions of the three best flying peptides per proteins (TopPep3/TopTra2) generated optimal results with a cross-correlated mean fold error of 1.8 and a squared Pearson coefficient R(2) of 0.88. Applying the optimized model to lysates of the microbe Leptospira interrogans, we detected significant protein abundance changes of 39 target proteins upon antibiotic treatment, which correlate well with literature values. The described method is generally applicable and exploits the inherent performance advantages of SRM

  13. A Helium-Cooled Absolute Cavity Radiometer For Solar And Laboratory Irradiance Measurement

    NASA Astrophysics Data System (ADS)

    Foukal, P.; Miller, P.

    1983-09-01

    We describe the design and testing of a helium-cooled absolute radiometer (HCAR) devel-oped for highly reproducible measurements of total solar irradiance and ultraviolet flux, and for laboratory standards uses. The receiver of this cryogenic radiometer is a blackened cone of pure copper whose temperature is sensed by a germanium resistance thermometer. During a duty cycle, radiant power input is compared to electrical heating in an accurate resistor wound on the receiver, as in conventional self-calibrating radiometers of the PACRAD and ACR type. But operation at helium temperatures enables us to achieve excellent radia-tive shielding between the receiver and the radiometer thermal background. This enables us to attain a sensitivity level of 10-7 watts at 30 seconds integration time, at least 10 times better than achieved by room temperature cavities. The dramatic drop of copper specific heat at helium temperatures reduces the time constant for a given mass of receiver, by a factor of 103. Together with other cryogenic materials properties such as electrical superconductivity and the high thermal conductivity of copper, this can be used to greatly reduce non-equivalence errors between electrical and radiant heating, that presently limit the absolute accuracy of radiometers to approximately 0,2%. Absolute accuracy of better than 0.01% has been achieved with a similar cryogenic radiometer in laboratory measurements of the Stefan-Boltzmann constant at NPL in the U.K. Electrical and radiometric tests con-ducted so far on our prototype indicate that comparable accuracy and long-term reproducibility can be achieved in a versatile instrument of manageable size for Shuttle flight and laboratory standards uses. This work is supported at AER under NOAA contract NA8ORAC00204 and NSF grant DMR-8260273.

  14. The photometric properties of brightest cluster galaxies. I - Absolute magnitudes in 116 nearby Abell clusters

    NASA Technical Reports Server (NTRS)

    Hoessel, J. G.; Gunn, J. E.; Thuan, T. X.

    1980-01-01

    Two-color aperture photometry of the brightest galaxies in a complete sample of nearby Abell clusters is presented. The results are used to anchor the bright end of the Hubble diagram; essentially the entire formal error for this method is then due to the sample of distant clusters used. New determinations of the systematic trend of galaxy absolute magnitude with the cluster properties of richness and Bautz-Morgan type are derived. When these new results are combined with the Gunn and Oke (1975) data on high-redshift clusters, a formal value (without accounting for any evolution) of q sub 0 = -0.55 + or - 0.45 (1 standard deviations) is found.

  15. Absolute judgment for one- and two-dimensional stimuli embedded in Gaussian noise

    NASA Technical Reports Server (NTRS)

    Kvalseth, T. O.

    1977-01-01

    This study examines the effect on human performance of adding Gaussian noise or disturbance to the stimuli in absolute judgment tasks involving both one- and two-dimensional stimuli. For each selected stimulus value (both an X-value and a Y-value were generated in the two-dimensional case), 10 values (or 10 pairs of values in the two-dimensional case) were generated from a zero-mean Gaussian variate, added to the selected stimulus value and then served as the coordinate values for the 10 points that were displayed sequentially on a CRT. The results show that human performance, in terms of the information transmitted and rms error as functions of stimulus uncertainty, was significantly reduced as the noise variance increased.

  16. Absolute tracer dye concentration using airborne laser-induced water Raman backscatter

    NASA Technical Reports Server (NTRS)

    Hoge, F. E.; Swift, R. N.

    1981-01-01

    The use of simultaneous airborne-laser-induced dye fluorescence and water Raman backscatter to measure the absolute concentration of an ocean-dispersed tracer dye is discussed. Theoretical considerations of the calculation of dye concentration by the numerical comparison of airborne laser-induced fluorescence spectra with laboratory spectra for known dye concentrations using the 3400/cm OH-stretch water Raman scatter as a calibration signal are presented which show that minimum errors are obtained and no data concerning water mass transmission properties are required when the laser wavelength is chosen to yield a Raman signal near the dye emission band. Results of field experiments conducted with an airborne conical scan lidar over a site in New York Bight into which rhodamine dye had been injected in a study of oil spill dispersion are then indicated which resulted in a contour map of dye concentrations, with a minimum detectable dye concentration of approximately 2 ppb by weight.

  17. Absolute Density Calibration Cell for Laser Induced Fluorescence Erosion Rate Measurements

    NASA Technical Reports Server (NTRS)

    Domonkos, Matthew T.; Stevens, Richard E.

    2001-01-01

    Flight qualification of ion thrusters typically requires testing on the order of 10,000 hours. Extensive knowledge of wear mechanisms and rates is necessary to establish design confidence prior to long duration tests. Consequently, real-time erosion rate measurements offer the potential both to reduce development costs and to enhance knowledge of the dependency of component wear on operating conditions. Several previous studies have used laser-induced fluorescence (LIF) to measure real-time, in situ erosion rates of ion thruster accelerator grids. Those studies provided only relative measurements of the erosion rate. In the present investigation, a molybdenum tube was resistively heated such that the evaporation rate yielded densities within the tube on the order of those expected from accelerator grid erosion. This work examines the suitability of the density cell as an absolute calibration source for LIF measurements, and the intrinsic error was evaluated.

  18. Assessment of absolute added correlative coding in optical intensity modulation and direct detection channels

    NASA Astrophysics Data System (ADS)

    Dong-Nhat, Nguyen; Elsherif, Mohamed A.; Malekmohammadi, Amin

    2016-06-01

    The performance of absolute added correlative coding (AACC) modulation format with direct detection has been numerically and analytically reported, targeting metro data center interconnects. Hereby, the focus lies on the performance of the bit error rate, noise contributions, spectral efficiency, and chromatic dispersion tolerance. The signal space model of AACC, where the average electrical and optical power expressions are derived for the first time, is also delineated. The proposed modulation format was also compared to other well-known signaling, such as on-off-keying (OOK) and four-level pulse-amplitude modulation, at the same bit rate in a directly modulated vertical-cavity surface-emitting laser-based transmission system. The comparison results show a clear advantage of AACC in achieving longer fiber delivery distance due to the higher dispersion tolerance.

  19. Online recognition of music is influenced by relative and absolute pitch information.

    PubMed

    Creel, Sarah C; Tumlin, Melanie A

    2012-03-01

    Three experiments explored online recognition in a nonspeech domain, using a novel experimental paradigm. Adults learned to associate abstract shapes with particular melodies, and at test they identified a played melody's associated shape. To implicitly measure recognition, visual fixations to the associated shape versus a distractor shape were measured as the melody played. Degree of similarity between associated melodies was varied to assess what types of pitch information adults use in recognition. Fixation and error data suggest that adults naturally recognize music, like language, incrementally, computing matches to representations before melody offset, despite the fact that music, unlike language, provides no pressure to execute recognition rapidly. Further, adults use both absolute and relative pitch information in recognition. The implicit nature of the dependent measure should permit use with a range of populations to evaluate postulated developmental and evolutionary changes in pitch encoding. PMID:22039917

  20. System and method for calibrating a rotary absolute position sensor

    NASA Technical Reports Server (NTRS)

    Davis, Donald R. (Inventor); Permenter, Frank Noble (Inventor); Radford, Nicolaus A (Inventor)

    2012-01-01

    A system includes a rotary device, a rotary absolute position (RAP) sensor generating encoded pairs of voltage signals describing positional data of the rotary device, a host machine, and an algorithm. The algorithm calculates calibration parameters usable to determine an absolute position of the rotary device using the encoded pairs, and is adapted for linearly-mapping an ellipse defined by the encoded pairs to thereby calculate the calibration parameters. A method of calibrating the RAP sensor includes measuring the rotary position as encoded pairs of voltage signals, linearly-mapping an ellipse defined by the encoded pairs to thereby calculate the calibration parameters, and calculating an absolute position of the rotary device using the calibration parameters. The calibration parameters include a positive definite matrix (A) and a center point (q) of the ellipse. The voltage signals may include an encoded sine and cosine of a rotary angle of the rotary device.

  1. Method and apparatus for two-dimensional absolute optical encoding

    NASA Technical Reports Server (NTRS)

    Leviton, Douglas B. (Inventor)

    2004-01-01

    This invention presents a two-dimensional absolute optical encoder and a method for determining position of an object in accordance with information from the encoder. The encoder of the present invention comprises a scale having a pattern being predetermined to indicate an absolute location on the scale, means for illuminating the scale, means for forming an image of the pattern; and detector means for outputting signals derived from the portion of the image of the pattern which lies within a field of view of the detector means, the field of view defining an image reference coordinate system, and analyzing means, receiving the signals from the detector means, for determining the absolute location of the object. There are two types of scale patterns presented in this invention: grid type and starfield type.

  2. Absolute and Convective Instability in Fluid-Conveying Flexible Pipes

    NASA Astrophysics Data System (ADS)

    de Langre, E.; Ouvrard, A. E.

    1998-11-01

    The effect of internal plug flow on the lateral stability of fluid conveying flexible pipes is investigated by determining the absolute/convective nature of the instability from the analytically derived linear dispersion relation. The fluid-structure interaction is modeled following the work of Gregory and Paidoussis (1966). The different domains of stability, convective instability, and absolute instability are explicitly derived in parameter space. The effect of flow velocity, mass ratio between the fluid and the structure, stiffness of the elastic foundation and axial tension is considered. Absolute instability prevails over a wide range of parameters. Convective instability only takes place at very high mass ratio, small stiffness and small axial tension. Relation is made with previous work of Brazier-Smith & Scott (1984) and Crighton (1991), considered here as a short wave approximation.

  3. Absolute intensity and polarization of rotational Raman scattering from N2, O2, and CO2

    NASA Technical Reports Server (NTRS)

    Penney, C. M.; St.peters, R. L.; Lapp, M.

    1973-01-01

    An experimental examination of the absolute intensity, polarization, and relative line intensities of rotational Raman scattering (RRS) from N2, O2, and CO2 is reported. The absolute scattering intensity for N2 is characterized by its differential cross section for backscattering of incident light at 647.1 nm, which is calculated from basic measured values. The ratio of the corresponding cross section for O2 to that for N2 is 2.50 plus or minus 5 percent. The intensity recent for N2, O2, and CO2 are shown to compare favorably to values calculated from recent measurements of the depolarization of Rayleigh scattering plus RRS. Measured depolarizations of various RRS lines agree to within a few percent with the theoretical value of 3/4. Detailed error analyses are presented for intensity and depolarization measurements. Finally, extensive RRS spectra at nominal gas temperatures of 23 C, 75 C, and 125 C are presented and shown to compare favorably to theoretical predictions.

  4. Absolute frequency stabilization of an injection-seeded optical parametric oscillator

    SciTech Connect

    Plusquellic, D.F.; Votava, O.; Nesbitt, D.J.

    1996-03-01

    A method is described that provides absolute frequency stabilization and calibration of the signal and idler waves generated by an injection-seeded optical parametric oscillator (OPO). The method makes use of a He{endash}Ne stabilized transfer cavity (TC) to control the frequencies of the cw sources used to seed both the pump laser and OPO cavity. The TC serves as a stable calibration source for the signal and idler waves by providing marker fringes as the seed laser is scanned. Additionally, an acoustic-optic modulator (AOM) is used to shift the OPO seed laser{close_quote}s frequency before locking it onto the TC. The sidebands of the AOM are tunable over more than one free spectral range of the TC, thereby permitting stabilization of the signal and idler waves at any frequency. A {plus_minus}25-MHz residual error in the absolute frequency stabilities of the pump, signal, and idler waves is experimentally demonstrated, which is roughly 30{percent} of the 160-MHz near-transform-limited linewidths of the signal and idler pulses. {copyright} {ital 1996 Optical Society of America.}

  5. Use of the absolute phase in frequency modulated continuous wave plasma reflectometry

    SciTech Connect

    Cunningham, G.

    2008-08-15

    In frequency modulated continuous wave reflectometry, used for density profile measurement in fusion plasmas, it is usual to measure the beat frequency between the launched wave and the reflected wave, and from this to calculate the position of the reflecting layer in the plasma. The absolute phase of the beat signal is usually neglected. The reason is that the phase shift between sweeps is usually comparable with or more than 2{pi}, leading to an ambiguity that is impossible to resolve. However, recent observations on the MAST tokamak have shown that, under quiet plasma conditions (this term has to be defined), the phase shift between sweeps is small compared with 2{pi} and the phase ambiguity can be readily resolved. The reflectometer signal is then being analyzed as an interferometer signal would normally be, and there is a substantial improvement in spatial resolution. The method is illustrated by application to small edge localized mode precursor and allows what is believed to be the first quantitative measurement of the displacement of the plasma boundary by such a precursor mode. The errors in both the absolute phase measurement and the more conventional frequency measurement are also estimated.

  6. Robust characterization of leakage errors

    NASA Astrophysics Data System (ADS)

    Wallman, Joel J.; Barnhill, Marie; Emerson, Joseph

    2016-04-01

    Leakage errors arise when the quantum state leaks out of some subspace of interest, for example, the two-level subspace of a multi-level system defining a computational ‘qubit’, the logical code space of a quantum error-correcting code, or a decoherence-free subspace. Leakage errors pose a distinct challenge to quantum control relative to the more well-studied decoherence errors and can be a limiting factor to achieving fault-tolerant quantum computation. Here we present a scalable and robust randomized benchmarking protocol for quickly estimating the leakage rate due to an arbitrary Markovian noise process on a larger system. We illustrate the reliability of the protocol through numerical simulations.

  7. Static Detection of Disassembly Errors

    SciTech Connect

    Krishnamoorthy, Nithya; Debray, Saumya; Fligg, Alan K

    2009-10-13

    Static disassembly is a crucial first step in reverse engineering executable files, and there is a consider- able body of work in reverse-engineering of binaries, as well as areas such as semantics-based security anal- ysis, that assumes that the input executable has been correctly disassembled. However, disassembly errors, e.g., arising from binary obfuscations, can render this assumption invalid. This work describes a machine- learning-based approach, using decision trees, for stat- ically identifying possible errors in a static disassem- bly; such potential errors may then be examined more closely, e.g., using dynamic analyses. Experimental re- sults using a variety of input executables indicate that our approach performs well, correctly identifying most disassembly errors with relatively few false positives.

  8. Orbital and Geodetic Error Analysis

    NASA Technical Reports Server (NTRS)

    Felsentreger, T.; Maresca, P.; Estes, R.

    1985-01-01

    Results that previously required several runs determined in more computer-efficient manner. Multiple runs performed only once with GEODYN and stored on tape. ERODYN then performs matrix partitioning and linear algebra required for each individual error-analysis run.

  9. Prospective errors determine motor learning.

    PubMed

    Takiyama, Ken; Hirashima, Masaya; Nozaki, Daichi

    2015-01-01

    Diverse features of motor learning have been reported by numerous studies, but no single theoretical framework concurrently accounts for these features. Here, we propose a model for motor learning to explain these features in a unified way by extending a motor primitive framework. The model assumes that the recruitment pattern of motor primitives is determined by the predicted movement error of an upcoming movement (prospective error). To validate this idea, we perform a behavioural experiment to examine the model's novel prediction: after experiencing an environment in which the movement error is more easily predictable, subsequent motor learning should become faster. The experimental results support our prediction, suggesting that the prospective error might be encoded in the motor primitives. Furthermore, we demonstrate that this model has a strong explanatory power to reproduce a wide variety of motor-learning-related phenomena that have been separately explained by different computational models. PMID:25635628

  10. Human errors and measurement uncertainty

    NASA Astrophysics Data System (ADS)

    Kuselman, Ilya; Pennecchi, Francesca

    2015-04-01

    Evaluating the residual risk of human errors in a measurement and testing laboratory, remaining after the error reduction by the laboratory quality system, and quantifying the consequences of this risk for the quality of the measurement/test results are discussed based on expert judgments and Monte Carlo simulations. A procedure for evaluation of the contribution of the residual risk to the measurement uncertainty budget is proposed. Examples are provided using earlier published sets of expert judgments on human errors in pH measurement of groundwater, elemental analysis of geological samples by inductively coupled plasma mass spectrometry, and multi-residue analysis of pesticides in fruits and vegetables. The human error contribution to the measurement uncertainty budget in the examples was not negligible, yet also not dominant. This was assessed as a good risk management result.

  11. Quantum error correction beyond qubits

    NASA Astrophysics Data System (ADS)

    Aoki, Takao; Takahashi, Go; Kajiya, Tadashi; Yoshikawa, Jun-Ichi; Braunstein, Samuel L.; van Loock, Peter; Furusawa, Akira

    2009-08-01

    Quantum computation and communication rely on the ability to manipulate quantum states robustly and with high fidelity. To protect fragile quantum-superposition states from corruption through so-called decoherence noise, some form of error correction is needed. Therefore, the discovery of quantum error correction (QEC) was a key step to turn the field of quantum information from an academic curiosity into a developing technology. Here, we present an experimental implementation of a QEC code for quantum information encoded in continuous variables, based on entanglement among nine optical beams. This nine-wave-packet adaptation of Shor's original nine-qubit scheme enables, at least in principle, full quantum error correction against an arbitrary single-beam error.

  12. Interpolation Errors in Spectrum Analyzers

    NASA Technical Reports Server (NTRS)

    Martin, J. L.

    1996-01-01

    To obtain the proper measurement amplitude with a spectrum analyzer, the correct frequency-dependent transducer factor must be added to the voltage measured by the transducer. This report examines how entering transducer factors into a spectrum analyzer can cause significant errors in field amplitude due to the misunderstanding of the analyzer's interpolation methods. It also discusses how to reduce these errors to obtain a more accurate field amplitude reading.

  13. Evaluation of centroiding algorithm error for Nano-JASMINE

    NASA Astrophysics Data System (ADS)

    Hara, Takuji; Gouda, Naoteru; Yano, Taihei; Yamada, Yoshiyuki

    2014-08-01

    The Nano-JASMINE mission has been designed to perform absolute astrometric measurements with unprecedented accuracy; the end-of-mission parallax standard error is required to be of the order of 3 milli arc seconds for stars brighter than 7.5 mag in the zw-band(0.6μm-1.0μm) .These requirements set a stringent constraint on the accuracy of the estimation of the location of the stellar image on the CCD for each observation. However each stellar images have individual shape depend on the spectral energy distribution of the star, the CCD properties, and the optics and its associated wave front errors. So it is necessity that the centroiding algorithm performs a high accuracy in any observables. Referring to the study of Gaia, we use LSF fitting method for centroiding algorithm, and investigate systematic error of the algorithm for Nano-JASMINE. Furthermore, we found to improve the algorithm by restricting sample LSF when we use a Principle Component Analysis. We show that centroiding algorithm error decrease after adapted the method.

  14. Magnetospheric Multiscale (MMS) Mission Commissioning Phase Orbit Determination Error Analysis

    NASA Technical Reports Server (NTRS)

    Chung, Lauren R.; Novak, Stefan; Long, Anne; Gramling, Cheryl

    2009-01-01

    The Magnetospheric MultiScale (MMS) mission commissioning phase starts in a 185 km altitude x 12 Earth radii (RE) injection orbit and lasts until the Phase 1 mission orbits and orientation to the Earth-Sun li ne are achieved. During a limited time period in the early part of co mmissioning, five maneuvers are performed to raise the perigee radius to 1.2 R E, with a maneuver every other apogee. The current baseline is for the Goddard Space Flight Center Flight Dynamics Facility to p rovide MMS orbit determination support during the early commissioning phase using all available two-way range and Doppler tracking from bo th the Deep Space Network and Space Network. This paper summarizes th e results from a linear covariance analysis to determine the type and amount of tracking data required to accurately estimate the spacecraf t state, plan each perigee raising maneuver, and support thruster cal ibration during this phase. The primary focus of this study is the na vigation accuracy required to plan the first and the final perigee ra ising maneuvers. Absolute and relative position and velocity error hi stories are generated for all cases and summarized in terms of the ma ximum root-sum-square consider and measurement noise error contributi ons over the definitive and predictive arcs and at discrete times inc luding the maneuver planning and execution times. Details of the meth odology, orbital characteristics, maneuver timeline, error models, and error sensitivities are provided.

  15. Ocean spectral data assimilation without background error covariance matrix

    NASA Astrophysics Data System (ADS)

    Chu, Peter C.; Fan, Chenwu; Margolina, Tetyana

    2016-08-01

    Predetermination of background error covariance matrix B is challenging in existing ocean data assimilation schemes such as the optimal interpolation (OI). An optimal spectral decomposition (OSD) has been developed to overcome such difficulty without using the B matrix. The basis functions are eigenvectors of the horizontal Laplacian operator, pre-calculated on the base of ocean topography, and independent on any observational data and background fields. Minimization of analysis error variance is achieved by optimal selection of the spectral coefficients. Optimal mode truncation is dependent on the observational data and observational error variance and determined using the steep-descending method. Analytical 2D fields of large and small mesoscale eddies with white Gaussian noises inside a domain with four rigid and curved boundaries are used to demonstrate the capability of the OSD method. The overall error reduction using the OSD is evident in comparison to the OI scheme. Synoptic monthly gridded world ocean temperature, salinity, and absolute geostrophic velocity datasets produced with the OSD method and quality controlled by the NOAA National Centers for Environmental Information (NCEI) are also presented.

  16. On the effect of distortion and dispersion in fringe signal of the FG5 absolute gravimeters

    NASA Astrophysics Data System (ADS)

    Křen, Petr; Pálinkáš, Vojtech; Mašika, Pavel

    2016-02-01

    The knowledge of absolute gravity acceleration at the level of 1  ×  10-9 is needed in geosciences (e.g. for monitoring crustal deformations and mass transports) and in metrology for watt balance experiments related to the new SI definition of the unit of kilogram. The gravity reference, which results from the international comparisons held with the participation of numerous absolute gravimeters, is significantly affected by qualities of instruments prevailing in the comparisons (i.e. at present, FG5 gravimeters). Therefore, it is necessary to thoroughly investigate all instrumental (particularly systematic) errors. This paper deals with systematic errors of the FG5#215 coming from the distorted fringe signal and from the electronic dispersion at several electronic components including cables. In order to investigate these effects, we developed a new experimental system for acquiring and analysing the data parallel to the FG5 built-in system. The new system based on the analogue-to-digital converter with digital waveform processing using the FFT swept band pass filter is developed and tested on the FG5#215 gravimeter equipped with a new fast analogue output. The system is characterized by a low timing jitter, digital handling of the distorted swept signal with determination of zero-crossings for the fundamental frequency sweep and also for its harmonics and can be used for any gravimeter based on the laser interferometry. Comparison of the original FG5 system and the experimental systems is provided on g-values, residuals and additional measurements/models. Moreover, advanced approach for the solution of the free-fall motion is presented, which allows to take into account a non-linear gravity change with height.

  17. Medical Error and Moral Luck.

    PubMed

    Hubbeling, Dieneke

    2016-09-01

    This paper addresses the concept of moral luck. Moral luck is discussed in the context of medical error, especially an error of omission that occurs frequently, but only rarely has adverse consequences. As an example, a failure to compare the label on a syringe with the drug chart results in the wrong medication being administered and the patient dies. However, this error may have previously occurred many times with no tragic consequences. Discussions on moral luck can highlight conflicting intuitions. Should perpetrators receive a harsher punishment because of an adverse outcome, or should they be dealt with in the same way as colleagues who have acted similarly, but with no adverse effects? An additional element to the discussion, specifically with medical errors, is that according to the evidence currently available, punishing individual practitioners does not seem to be effective in preventing future errors. The following discussion, using relevant philosophical and empirical evidence, posits a possible solution for the moral luck conundrum in the context of medical error: namely, making a distinction between the duty to make amends and assigning blame. Blame should be assigned on the basis of actual behavior, while the duty to make amends is dependent on the outcome. PMID:26662613

  18. Error image aware content restoration

    NASA Astrophysics Data System (ADS)

    Choi, Sungwoo; Lee, Moonsik; Jung, Byunghee

    2015-12-01

    As the resolution of TV significantly increased, content consumers have become increasingly sensitive to the subtlest defect in TV contents. This rising standard in quality demanded by consumers has posed a new challenge in today's context where the tape-based process has transitioned to the file-based process: the transition necessitated digitalizing old archives, a process which inevitably produces errors such as disordered pixel blocks, scattered white noise, or totally missing pixels. Unsurprisingly, detecting and fixing such errors require a substantial amount of time and human labor to meet the standard demanded by today's consumers. In this paper, we introduce a novel, automated error restoration algorithm which can be applied to different types of classic errors by utilizing adjacent images while preserving the undamaged parts of an error image as much as possible. We tested our method to error images detected from our quality check system in KBS(Korean Broadcasting System) video archive. We are also implementing the algorithm as a plugin of well-known NLE(Non-linear editing system), which is a familiar tool for quality control agent.

  19. Non-Invasive Method of Determining Absolute Intracranial Pressure

    NASA Technical Reports Server (NTRS)

    Yost, William T. (Inventor); Cantrell, John H., Jr. (Inventor); Hargens, Alan E. (Inventor)

    2004-01-01

    A method is presented for determining absolute intracranial pressure (ICP) in a patient. Skull expansion is monitored while changes in ICP are induced. The patient's blood pressure is measured when skull expansion is approximately zero. The measured blood pressure is indicative of a reference ICP value. Subsequently, the method causes a known change in ICP and measured the change in skull expansion associated therewith. The absolute ICP is a function of the reference ICP value, the known change in ICP and its associated change in skull expansion; and a measured change in skull expansion.

  20. Measurements of the reactor neutron power in absolute units

    NASA Astrophysics Data System (ADS)

    Lebedev, G. V.

    2015-12-01

    The neutron power of the reactor of the Yenisei space nuclear power plant is measured in absolute units using the modernized method of correlation analysis during the ground-based tests of the Yenisei prototypes. Results of the experiments are given. The desired result is obtained in a series of experiments carried out at the stage of the plant preparation for tests. The acceptability of experimental data is confirmed by the results of measuring the reactor neutron power in absolute units at the nominal level by the thermal balance during the life cycle tests of the ground prototypes.

  1. In-flight absolute radiometric calibration of the thematic mapper

    NASA Technical Reports Server (NTRS)

    Castle, K. R.; Holm, R. G.; Kastner, C. J.; Palmer, J. M.; Slater, P. N.; Dinguirard, M.; Ezra, C. E.; Jackson, R. D.; Savage, R. K.

    1983-01-01

    The TM multispectral scanner system was calibrated in an absolute manner before launch. To determine the temporal changes of the absolute radiometric calibration of the entire system, spectroradiometric measurements of the ground and the atmosphere were made simultaneously with TM collections over White Sands, New Mexico. By entering the measured values in an atmospheric radiative transfer program, the radiance levels of the in four of the spectral bands of the TM were determined. Tables show values for the reflectance of snow at White Sands measured by a modular 8 channel radiometer, and values for exoatmospheric irradiance within the TM passbands, calculated for the Earth-Sun distance using a solar radiometer.

  2. Absolute photon-flux measurements in the vacuum ultraviolet

    NASA Technical Reports Server (NTRS)

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

    1974-01-01

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

  3. Notes on Van der Meer scan for absolute luminosity measurement

    NASA Astrophysics Data System (ADS)

    Balagura, Vladislav

    2011-10-01

    The absolute luminosity can be measured in an accelerator by sweeping beams transversely across each other in the so-called van der Meer scan. We prove that the method can be applied in the general case of arbitrary beam directions and a separation scan plane. A simple method to develop an image of the beam in its transverse plane from spatial distributions of interaction vertexes is also proposed. From the beam images one can determine their overlap and the absolute luminosity. This provides an alternative way of the luminosity measurement during van der Meer scan.

  4. Measurements of the reactor neutron power in absolute units

    SciTech Connect

    Lebedev, G. V.

    2015-12-15

    The neutron power of the reactor of the Yenisei space nuclear power plant is measured in absolute units using the modernized method of correlation analysis during the ground-based tests of the Yenisei prototypes. Results of the experiments are given. The desired result is obtained in a series of experiments carried out at the stage of the plant preparation for tests. The acceptability of experimental data is confirmed by the results of measuring the reactor neutron power in absolute units at the nominal level by the thermal balance during the life cycle tests of the ground prototypes.

  5. Absolute Stability Analysis of a Phase Plane Controlled Spacecraft

    NASA Technical Reports Server (NTRS)

    Jang, Jiann-Woei; Plummer, Michael; Bedrossian, Nazareth; Hall, Charles; Jackson, Mark; Spanos, Pol

    2010-01-01

    Many aerospace attitude control systems utilize phase plane control schemes that include nonlinear elements such as dead zone and ideal relay. To evaluate phase plane control robustness, stability margin prediction methods must be developed. Absolute stability is extended to predict stability margins and to define an abort condition. A constrained optimization approach is also used to design flex filters for roll control. The design goal is to optimize vehicle tracking performance while maintaining adequate stability margins. Absolute stability is shown to provide satisfactory stability constraints for the optimization.

  6. A general relativistic model for free-fall absolute gravimeters

    NASA Astrophysics Data System (ADS)

    Tan, Yu-Jie; Shao, Cheng-Gang; Li, Jia; Hu, Zhong-Kun

    2016-04-01

    Although the relativistic manifestations of gravitational fields in gravimetry were first studied 40 years ago, the relativistic effects combined with free-fall absolute gravimeters have rarely been considered. In light of this, we present a general relativistic model for free-fall absolute gravimeters in a local-Fermi coordinates system, where we focus on effects related to the measuring devices: relativistic transverse Doppler effects, gravitational redshift effects and Earth’s rotation effects. Based on this model, a general relativistic expression of the measured gravity acceleration is obtained.

  7. Reducing systematic error in weak lensing cluster surveys

    SciTech Connect

    Utsumi, Yousuke; Miyazaki, Satoshi; Hamana, Takashi; Geller, Margaret J.; Kurtz, Michael J.; Fabricant, Daniel G.; Dell'Antonio, Ian P.; Oguri, Masamune

    2014-05-10

    Weak lensing provides an important route toward collecting samples of clusters of galaxies selected by mass. Subtle systematic errors in image reduction can compromise the power of this technique. We use the B-mode signal to quantify this systematic error and to test methods for reducing this error. We show that two procedures are efficient in suppressing systematic error in the B-mode: (1) refinement of the mosaic CCD warping procedure to conform to absolute celestial coordinates and (2) truncation of the smoothing procedure on a scale of 10'. Application of these procedures reduces the systematic error to 20% of its original amplitude. We provide an analytic expression for the distribution of the highest peaks in noise maps that can be used to estimate the fraction of false peaks in the weak-lensing κ-signal-to-noise ratio (S/N) maps as a function of the detection threshold. Based on this analysis, we select a threshold S/N = 4.56 for identifying an uncontaminated set of weak-lensing peaks in two test fields covering a total area of ∼3 deg{sup 2}. Taken together these fields contain seven peaks above the threshold. Among these, six are probable systems of galaxies and one is a superposition. We confirm the reliability of these peaks with dense redshift surveys, X-ray, and imaging observations. The systematic error reduction procedures we apply are general and can be applied to future large-area weak-lensing surveys. Our high-peak analysis suggests that with an S/N threshold of 4.5, there should be only 2.7 spurious weak-lensing peaks even in an area of 1000 deg{sup 2}, where we expect ∼2000 peaks based on our Subaru fields.

  8. On the correct representation of bending and axial deformation in the absolute nodal coordinate formulation with an elastic line approach

    NASA Astrophysics Data System (ADS)

    Gerstmayr, Johannes; Irschik, Hans

    2008-12-01

    In finite element methods that are based on position and slope coordinates, a representation of axial and bending deformation by means of an elastic line approach has become popular. Such beam and plate formulations based on the so-called absolute nodal coordinate formulation have not yet been verified sufficiently enough with respect to analytical results or classical nonlinear rod theories. Examining the existing planar absolute nodal coordinate element, which uses a curvature proportional bending strain expression, it turns out that the deformation does not fully agree with the solution of the geometrically exact theory and, even more serious, the normal force is incorrect. A correction based on the classical ideas of the extensible elastica and geometrically exact theories is applied and a consistent strain energy and bending moment relations are derived. The strain energy of the solid finite element formulation of the absolute nodal coordinate beam is based on the St. Venant-Kirchhoff material: therefore, the strain energy is derived for the latter case and compared to classical nonlinear rod theories. The error in the original absolute nodal coordinate formulation is documented by numerical examples. The numerical example of a large deformation cantilever beam shows that the normal force is incorrect when using the previous approach, while a perfect agreement between the absolute nodal coordinate formulation and the extensible elastica can be gained when applying the proposed modifications. The numerical examples show a very good agreement of reference analytical and numerical solutions with the solutions of the proposed beam formulation for the case of large deformation pre-curved static and dynamic problems, including buckling and eigenvalue analysis. The resulting beam formulation does not employ rotational degrees of freedom and therefore has advantages compared to classical beam elements regarding energy-momentum conservation.

  9. Absolute determination of inelastic mean-free paths and surface excitation parameters by absolute reflection electron energy loss spectrum analysis

    NASA Astrophysics Data System (ADS)

    Nagatomi, T.; Goto, K.

    2005-11-01

    An analytical approach was proposed for simultaneously determining an inelastic mean-free path (IMFP) and a surface excitation parameter (SEP) with absolute units by the analysis of an absolute experimental reflection electron energy loss spectrum. The IMFPs and SEPs in Ni were deduced for electrons of 300 to 3000 eV. The obtained IMFPs were in good agreement with those calculated using the TPP-2M equation. The Chen-type empirical formula was proposed for determining the SEP. The results confirmed the applicability of the present approach for determining the IMFP and SEP for medium-energy electrons.

  10. Error Detection Processes in Problem Solving.

    ERIC Educational Resources Information Center

    Allwood, Carl Martin

    1984-01-01

    Describes a study which analyzed problem solvers' error detection processes by instructing subjects to think aloud when solving statistical problems. Effects of evaluative episodes on error detection, detection of different error types, error detection processes per se, and relationship of error detection behavior to problem-solving proficiency…

  11. Error-associated behaviors and error rates for robotic geology

    NASA Technical Reports Server (NTRS)

    Anderson, Robert C.; Thomas, Geb; Wagner, Jacob; Glasgow, Justin

    2004-01-01

    This study explores human error as a function of the decision-making process. One of many models for human decision-making is Rasmussen's decision ladder [9]. The decision ladder identifies the multiple tasks and states of knowledge involved in decision-making. The tasks and states of knowledge can be classified by the level of cognitive effort required to make the decision, leading to the skill, rule, and knowledge taxonomy (Rasmussen, 1987). Skill based decisions require the least cognitive effort and knowledge based decisions require the greatest cognitive effort. Errors can occur at any of the cognitive levels.

  12. Series that Converge Absolutely but Don't Converge

    ERIC Educational Resources Information Center

    Kantrowitz, Robert; Schramm, Michael

    2012-01-01

    If a series of real numbers converges absolutely, then it converges. The usual proof requires completeness in the form of the Cauchy criterion. Failing completeness, the result is false. We provide examples of rational series that illustrate this point. The Cantor set appears in connection with one of the examples.

  13. Population-based absolute risk estimation with survey data.

    PubMed

    Kovalchik, Stephanie A; Pfeiffer, Ruth M

    2014-04-01

    Absolute risk is the probability that a cause-specific event occurs in a given time interval in the presence of competing events. We present methods to estimate population-based absolute risk from a complex survey cohort that can accommodate multiple exposure-specific competing risks. The hazard function for each event type consists of an individualized relative risk multiplied by a baseline hazard function, which is modeled nonparametrically or parametrically with a piecewise exponential model. An influence method is used to derive a Taylor-linearized variance estimate for the absolute risk estimates. We introduce novel measures of the cause-specific influences that can guide modeling choices for the competing event components of the model. To illustrate our methodology, we build and validate cause-specific absolute risk models for cardiovascular and cancer deaths using data from the National Health and Nutrition Examination Survey. Our applications demonstrate the usefulness of survey-based risk prediction models for predicting health outcomes and quantifying the potential impact of disease prevention programs at the population level. PMID:23686614

  14. Invalid phase values removal method for absolute phase recovery.

    PubMed

    Lu, Jin; Mo, Rong; Sun, Huibin; Chang, Zhiyong; Zhao, Xiaxia

    2016-01-10

    A novel approach is presented for more effectively removing invalid phase values in absolute phase recovery. The approach is based on a detailed study involving the types and cases of invalid phase values. Meanwhile, some commonalities of the existing removal algorithms also are thoroughly analyzed. It is well known that rough absolute phase and fringe order maps can very easily be obtained by temporal phase unwrapping techniques. After carefully analyzing the components and fringe order distribution of the rough fringe order map, the proposed method chiefly adopts an entirely new strategy to refine a pure fringe order map. The strategy consists of three parts: (1) the square of an image gradient, (2) subregion areas of the binary image, and (3) image decomposition and composition. In combination with the pure fringe order map and a removal criterion, the invalid phase values can be identified and filtered out from the rough absolute phase map. This new strategy not only gets rid of the limitations of traditional removal methods but also has a two-fold function. The paper also offers different metrics from the experiment to evaluate the quality of the final absolute phase. In contrast with other removal methods, experimental results have verified the feasibility, effectiveness, and superiority of the proposed method. PMID:26835776

  15. Absolute Value Inequalities: High School Students' Solutions and Misconceptions

    ERIC Educational Resources Information Center

    Almog, Nava; Ilany, Bat-Sheva

    2012-01-01

    Inequalities are one of the foundational subjects in high school math curricula, but there is a lack of academic research into how students learn certain types of inequalities. This article fills part of the research gap by presenting the findings of a study that examined high school students' methods of approaching absolute value inequalities,…

  16. Lyman alpha SMM/UVSP absolute calibration and geocoronal correction

    NASA Technical Reports Server (NTRS)

    Fontenla, Juan M.; Reichmann, Edwin J.

    1987-01-01

    Lyman alpha observations from the Ultraviolet Spectrometer Polarimeter (UVSP) instrument of the Solar Maximum Mission (SMM) spacecraft were analyzed and provide instrumental calibration details. Specific values of the instrument quantum efficiency, Lyman alpha absolute intensity, and correction for geocoronal absorption are presented.

  17. An improved generalized Newton method for absolute value equations.

    PubMed

    Feng, Jingmei; Liu, Sanyang

    2016-01-01

    In this paper, we suggest and analyze an improved generalized Newton method for solving the NP-hard absolute 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 accuracy of calculation. PMID:27462490

  18. Relative versus Absolute Stimulus Control in the Temporal Bisection Task

    ERIC Educational Resources Information Center

    de Carvalho, Marilia Pinhiero; Machado, Armando

    2012-01-01

    When subjects learn to associate two sample durations with two comparison keys, do they learn to associate the keys with the short and long samples (relational hypothesis), or with the specific sample durations (absolute hypothesis)? We exposed 16 pigeons to an ABA design in which phases A and B corresponded to tasks using samples of 1 s and 4 s,…

  19. Absolute calibration of Landsat instruments using the moon.

    USGS Publications Warehouse

    Kieffer, H.H.; Wildey, R.L.

    1985-01-01

    A lunar observation by Landsat could provide improved radiometric and geometric calibration of both the Thematic Mapper and the Multispectral Scanner in terms of absolute radiometry, determination of the modulation transfer function, and sensitivity to scattered light. A pitch of the spacecraft would be required. -Authors

  20. Absence of absolutely continuous spectrum for random scattering zippers

    NASA Astrophysics Data System (ADS)

    Boumaza, Hakim; Marin, Laurent

    2015-02-01

    A scattering zipper is a system obtained by concatenation of scattering events with equal even number of incoming and outgoing channels. The associated scattering zipper operator is the unitary analog of Jacobi matrices with matrix entries. For infinite identical events and independent and identically distributed random phases, Lyapunov exponents positivity is proved and yields absence of absolutely continuous spectrum by Kotani's theory.

  1. 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,…

  2. Multifrequency continuous wave terahertz spectroscopy for absolute thickness determination

    SciTech Connect

    Scheller, Maik; Baaske, Kai; Koch, Martin

    2010-04-12

    We present a tunable multifrequency continuous wave terahertz spectrometer based on two laser diodes, photoconductive antennas, and a coherent detection scheme. The system is employed to determine the absolute thickness of samples utilizing a proposed synthetic difference frequency method to circumvent the 2pi uncertainty known from conventional photomixing systems while preserving a high spatial resolution.

  3. Ion chambers simplify absolute intensity measurements in the vacuum ultraviolet

    NASA Technical Reports Server (NTRS)

    Sampson, J. A. R.

    1966-01-01

    Single or double ion chamber technique measures absolute radiation intensities in the extreme vacuum ultraviolet region of the spectrum. The ion chambers use rare gases as the ion carrier. Photon absorbed by the gas creates one ion pair so a measure of these is a measure of the number of incident photons.

  4. Urey: to measure the absolute age of Mars

    NASA Technical Reports Server (NTRS)

    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.

    2003-01-01

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

  5. Is There a Rule of Absolute Neutralization in Nupe?

    ERIC Educational Resources Information Center

    Krohn, Robert

    1975-01-01

    A previously prosed rule of absolute neutralization (merging underlying low vowels) is eliminated in an alternative analysis including instead a rule that "breaks" the feature matrix of certain low vowels and redistributes the features of each vowel as a sequence of vowel-like transition plus (a). (Author/RM)

  6. Assignment of absolute stereochemistry by computation of optical rotation angles

    NASA Astrophysics Data System (ADS)

    Kondru, Rama Krishna

    We have developed simple wire and molecular orbital models to qualitatively and quantitatively understand optical rotation angles of molecules. We reported the first ab initio theoretical approach to determine the absolute stereochemistry of a complex natural product by calculating molar rotation angles, [M]D. We applied this method for an unambiguous assignment of the absolute stereochemistry of the hennoxazole A. A protocol analogous to population analysis was devised to analyze atomic contributions to the rotation angles for oxiranes, orthoesters, and other organic compounds. The molar rotations for an indoline, an indonone, menthol and menthone were calculated using ab inito methods and compared with experimental values. We reported the first prediction of the absolute configuration of a natural product, i.e. an a priori assignment of the relative and absolute stereochemistry of pitiamide A. Furthermore, we described a strategy that may help to establish structure-function relations for rotation angles by visualizing the electric and magnetic-field perturbations to a molecule's molecular orbitals.

  7. Hitting the target: relatively easy, yet absolutely difficult.

    PubMed

    Mapp, Alistair P; Ono, Hiroshi; Khokhotva, Mykola

    2007-01-01

    It is generally agreed that absolute-direction judgments require information about eye position, whereas relative-direction judgments do not. The source of this eye-position information, particularly during monocular viewing, is a matter of debate. It may be either binocular eye position, or the position of the viewing-eye only, that is crucial. Using more ecologically valid stimulus situations than the traditional LED in the dark, we performed two experiments. In experiment 1, observers threw darts at targets that were fixated either monocularly or binocularly. In experiment 2, observers aimed a laser gun at targets while fixating either the rear or the front gunsight monocularly, or the target either monocularly or binocularly. We measured the accuracy and precision of the observers' absolute- and relative-direction judgments. We found that (a) relative-direction judgments were precise and independent of phoria, and (b) monocular absolute-direction judgments were inaccurate, and the magnitude of the inaccuracy was predictable from the magnitude of phoria. These results confirm that relative-direction judgments do not require information about eye position. Moreover, they show that binocular eye-position information is crucial when judging the absolute direction of both monocular and binocular targets. PMID:17972479

  8. Absolute Risk Aversion and the Returns to Education.

    ERIC Educational Resources Information Center

    Brunello, Giorgio

    2002-01-01

    Uses 1995 Italian household income and wealth survey to measure individual absolute risk aversion of 1,583 married Italian male household heads. Uses this measure as an instrument for attained education in a standard-log earnings equation. Finds that the IV estimate of the marginal return to schooling is much higher than the ordinary least squares…

  9. Improved cavity-type absolute total-radiation radiometer

    NASA Technical Reports Server (NTRS)

    Kendall, J. M., Sr.; Plamondon, J. A., Jr.

    1967-01-01

    Conical cavity-type absolute radiometer measures the intensity of radiant energy to an accuracy of one to two percent in a vacuum of ten to the minus fifth torr or lower. There is a uniform response over the ultraviolet, visible, and infrared range, and it requires no calibration or comparison with a radiation standard.

  10. Absolute Interrogative Intonation Patterns in Buenos Aires Spanish

    ERIC Educational Resources Information Center

    Lee, Su Ar

    2010-01-01

    In Spanish, each uttered phrase, depending on its use, has one of a variety of intonation patterns. For example, a phrase such as "Maria viene manana" "Mary is coming tomorrow" can be used as a declarative or as an absolute interrogative (a yes/no question) depending on the intonation pattern that a speaker produces. Patterns of usage also…

  11. Absolute configurations of zingiberenols isolated from ginger (Zingiber officinale) rhizomes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The sesquiterpene alcohol zingiberenol, or 1,10-bisaboladien-3-ol, was isolated some time ago from ginger, Zingiber officinale, rhizomes, but its absolute configuration had not been determined. With three chiral centers present in the molecule, zingiberenol can exist in eight stereoisomeric forms. ...

  12. Research Note - Absolute UBV Photometry at the Zacatecas Observatory

    NASA Astrophysics Data System (ADS)

    Schuster, W. J.; Parrao, L.; Gonazlez-Bedolla, S. F.; Rios-Herrera, M.; Berumen, M. R.

    1985-12-01

    Atmospheric extinction data, color coefficients, errors of observation and a list of standard and comparison stars are given for UB V photometry at the Astronomical Observatory in Zacatecas. Our observing and reduction procedures are discussed briefly, and our extinction coefficients and observing errors compared with previous values. The uses of these results are mentioned.

  13. Four Years of Absolute Gravity in the Taiwan Orogen (AGTO)

    NASA Astrophysics Data System (ADS)

    Mouyen, Maxime; Masson, Frédéric; Hwang, Cheinway; Cheng, Ching-Chung; Le Moigne, Nicolas; Lee, Chiung-Wu; Kao, Ricky; Hsieh, Nicky

    2010-05-01

    AGTO is a scientific project between Taiwanese and French institutes, which aim is to improve tectonic knowledge of Taiwan primarily using absolute gravity measurements and permanent GPS stations. Both tools are indeed useful to study vertical movements and mass transfers involved in mountain building, a major process in Taiwan located at the convergent margin between Philippine Sea plate and Eurasian plate. This convergence results in two subductions north and south of Taiwan (Ryukyu and Manilla trenches, respectively), while the center is experiencing collision. These processes make Taiwan very active tectonically, as illustrated by numerous large earthquakes and rapid uplift of the Central Range. High slopes of Taiwan mountains and heavy rains brought by typhoons together lead to high landslides and mudflows risks. Practically, absolute gravity measurements have been yearly repeated since 2006 along a transect across south Taiwan, from Penghu to Lutao islands, using FG5 absolute gravimeters. This transect contains ten sites for absolute measurements and has been densified in 2008 by incorporating 45 sites for relative gravity measurements with CG5 gravimeters. The last relative and absolute measurements have been performed in November 2009. Most of the absolute sites have been measured with a good accuracy, about 1 or 2 ?Gal. Only the site located in Tainan University has higher standard deviation, due to the city noise. We note that absolute gravity changes seem to follow a trend in every site. However, straightforward tectonic interpretation of these trends is not valuable as many non-tectonic effects are supposed to change g with time, like groundwater or erosion. Estimating and removing these effects leads to a tectonic gravity signal, which has theoretically two origins : deep mass transfers around the site and vertical movements of the station. The latter can be well constrained by permanent GPS stations located close to the measurement pillar. Deep mass

  14. Four Years of Absolute Gravity in the Taiwan Orogen (AGTO)

    NASA Astrophysics Data System (ADS)

    Mouyen, M.; Masson, F.; Hwang, C.; Cheng, C.; Le Moigne, N.; Lee, C.; Kao, R.; Hsieh, N.

    2009-12-01

    AGTO is a scientific project between Taiwanese and French institutes which aim is to improve tectonic knowledge of Taiwan primarily using absolute gravity measurements and permanent GPS stations. Both tools are indeed useful to study vertical movements and mass transfers involved in mountain building, a major process in Taiwan located at the convergent margin between Philippine Sea plate and Eurasian plate. This convergence results in two subductions north and south of Taiwan (Ryukyu and Manilla trenches, respectively), while the center is experiencing collision. These processes make Taiwan very active tectonically, as illustrated by numerous large earthquakes and rapid uplift of the Central Range. High slopes of Taiwan mountains and heavy rains brought by typhoons together lead to high landslides and mudflows risks. Practically, absolute gravity measurements have been yearly repeated since 2006 along a transect across south Taiwan, from Penghu to Lutao island, using FG5 absolute gravimeters. This transect contains ten sites for absolute measurements and has been densified in 2008 by incorporating 45 sites for relative gravity measurements with CG5 gravimeters. At the end of 2009, the relative gravity network will be densified again in its eastern part, i.e. in the Longitudinal Valley and the Central Range. A fourth set of absolute gravity measurements will also be performed at the same period. Most of the absolute sites have been measured with a good accuracy, about 1 or 2 μGal. Only the site located in Tainan University has higher standard deviation, due to the city noise. The stronger change in gravity reaches -7 μGal a -1 west of the Longitudinal Valley and might be explained by tectonic movement along a fault. A large decrease of -5 μGal a-1 is also measured in Tainan city and could be correlated with uplift of this region, also denoted by InSAR, leveling and GPS. Changes occurring in the Central Range are more difficult to interpret due to the small

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

    NASA Technical Reports Server (NTRS)

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

    2012-01-01

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

  16. GNSS Absolute Antenna Calibration at the National Geodetic Survey

    NASA Astrophysics Data System (ADS)

    Mader, G. L.; Bilich, A. L.; Geoghegan, C.

    2011-12-01

    Geodetic GNSS applications routinely demand millimeter precision and extremely high levels of accuracy. To achieve these accuracies, 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 absolute 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 absolute calibrations. We demonstrate that NGS absolute phase center variation (PCV) patterns are consistent with published values determined by other absolute antenna calibration facilities, and compare absolute calibrations to the traditional NGS relative calibrations.

  17. Absolute Gravity Datum in the Age of Cold Atom Gravimeters

    NASA Astrophysics Data System (ADS)

    Childers, V. A.; Eckl, M. C.

    2014-12-01

    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 absolute meters) to replace the prior protocol of referencing all gravity values to the earlier Potsdam value. Since this time, 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 absolute gravimeters. This latest development is anticipated to provide improvement in the range of two orders of magnitude as compared to the measurement accuracy 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. Absolute gravimeters measure the total gravity field directly and do not involve ties to other measurements. Periodic "intercomparisons" of multiple absolute 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

  18. Absolute magnitudes and phase coefficients of trans-Neptunian objects

    NASA Astrophysics Data System (ADS)

    Alvarez-Candal, A.; Pinilla-Alonso, N.; Ortiz, J. L.; Duffard, R.; Morales, N.; Santos-Sanz, P.; Thirouin, A.; Silva, J. S.

    2016-02-01

    Context. Accurate measurements of diameters of trans-Neptunian objects (TNOs) are extremely difficult to obtain. Thermal modeling can provide good results, but accurate absolute magnitudes are needed to constrain the thermal models and derive diameters and geometric albedos. The absolute magnitude, HV, is defined as the magnitude of the object reduced to unit helio- and geocentric distances and a zero solar phase angle and is determined using phase curves. Phase coefficients can also be obtained from phase curves. These are related to surface properties, but only few are known. Aims: Our objective is to measure accurate V-band absolute magnitudes and phase coefficients for a sample of TNOs, many of which have been observed and modeled within the program "TNOs are cool", which is one of the Herschel Space Observatory key projects. Methods: We observed 56 objects using the V and R filters. These data, along with those available in the literature, were used to obtain phase curves and measure V-band absolute magnitudes and phase coefficients by assuming a linear trend of the phase curves and considering a magnitude variability that is due to the rotational light-curve. Results: We obtained 237 new magnitudes for the 56 objects, six of which were without previously reported measurements. Including the data from the literature, we report a total of 110 absolute magnitudes with their respective phase coefficients. The average value of HV is 6.39, bracketed by a minimum of 14.60 and a maximum of -1.12. For the phase coefficients we report a median value of 0.10 mag per degree and a very large dispersion, ranging from -0.88 up to 1.35 mag per degree.

  19. Spacecraft and propulsion technician error

    NASA Astrophysics Data System (ADS)

    Schultz, Daniel Clyde

    Commercial aviation and commercial space similarly launch, fly, and land passenger vehicles. Unlike aviation, the U.S. government has not established maintenance policies for commercial space. This study conducted a mixed methods review of 610 U.S. space launches from 1984 through 2011, which included 31 failures. An analysis of the failure causal factors showed that human error accounted for 76% of those failures, which included workmanship error accounting for 29% of the failures. With the imminent future of commercial space travel, the increased potential for the loss of human life demands that changes be made to the standardized procedures, training, and certification to reduce human error and failure rates. Several recommendations were made by this study to the FAA's Office of Commercial Space Transportation, space launch vehicle operators, and maintenance technician schools in an effort to increase the safety of the space transportation passengers.

  20. Error Field Correction in ITER

    SciTech Connect

    Park, Jong-kyu; Boozer, Allen H.; Menard, Jonathan E.; Schaffer, Michael J.

    2008-05-22

    A new method for correcting magnetic field errors in the ITER tokamak is developed using the Ideal Perturbed Equilibrium Code (IPEC). The dominant external magnetic field for driving islands is shown to be localized to the outboard midplane for three ITER equilibria that represent the projected range of operational scenarios. The coupling matrices between the poloidal harmonics of the external magnetic perturbations and the resonant fields on the rational surfaces that drive islands are combined for different equilibria and used to determine an ordered list of the dominant errors in the external magnetic field. It is found that efficient and robust error field correction is possible with a fixed setting of the correction currents relative to the currents in the main coils across the range of ITER operating scenarios that was considered.