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Berezhkovskii A.M.,United Information Technology
Chemical Physics | Year: 2010

Path integral based approach is used to analyze the variance of the residence time spent in a sub-domain by a particle diffusing in the presence of an arbitrary potential in a larger domain containing the sub-domain. It is assumed that there is no absorption of the particle within the domain or at its boundaries. Because of the ergodisity, the mean residence time in the sub-domain is a product of the observation time and the equilibrium probability of finding the particle in the sub-domain. We show that the variance also grows linearly with the observation time at large times and explain how the slope of this linear dependence can be found. The general approach is illustrated by simple examples, in which explicit formulas for the variance can be obtained. Source


Possolo A.,United Information Technology
Metrologia | Year: 2014

In the course of the twenty years since the publication of the Guide to the Expression of Uncertainty in Measurement (GUM), the recognition has been steadily growing of the value that statistical models and statistical computing bring to the evaluation of measurement uncertainty, and of how they enable its probabilistic interpretation. These models and computational methods can address all the problems originally discussed and illustrated in the GUM, and enable addressing other, more challenging problems, that measurement science is facing today and that it is expected to face in the years ahead. These problems that lie beyond the reach of the techniques in the GUM include (i) characterizing the uncertainty associated with the assignment of value to measurands of greater complexity than, or altogether different in nature from, the scalar or vectorial measurands entertained in the GUM: for example, sequences of nucleotides in DNA, calibration functions and optical and other spectra, spatial distribution of radioactivity over a geographical region, shape of polymeric scaffolds for bioengineering applications, etc; (ii) incorporating relevant information about the measurand that predates or is otherwise external to the measurement experiment; (iii) combining results from measurements of the same measurand that are mutually independent, obtained by different methods or produced by different laboratories. This review of several of these statistical models and computational methods illustrates some of the advances that they have enabled, and in the process invites a reflection on the interesting historical fact that these very same models and methods, by and large, were already available twenty years ago, when the GUM was first published - but then the dialogue between metrologists, statisticians and mathematicians was still in bud. It is in full bloom today, much to the benefit of all. © 2014 BIPM & IOP Publishing Ltd. Source


Rukhin A.L.,United Information Technology
Metrologia | Year: 2015

A problem that frequently occurs in metrology is the bias checking of data obtained by a laboratory against the specified value and uncertainty estimate given in the certificate of analysis. The measurand - a property of a certified reference material (CRM) - is supposed to be random with a normal distribution whose parameters are given by the certificate specifications. The laboratory's data from subsequent measurements of the CRM (a CRM experiment) are summarized by the sample mean value and its uncertainty which is commonly based on a repeatability standard deviation. New confidence intervals for the lab's bias are derived. Although they may lack intuitive appeal, those obtained by using higher order asymptotic methods, compared and contrasted in this paper, are recommended. © 2015 BIPM & IOP Publishing Ltd. Source


Jones E.B.,United Information Technology | Furukawa M.F.,Agency for Healthcare Research and Quality
Health Affairs | Year: 2014

Federally qualified health centers play an important role in providing health care to underserved populations. Recent substantial federal investments in health information technology have enabled health centers to expand their use of electronic health record (EHR) systems, but factors associated with adoption are not clear. We examined 2010-12 administrative data from the Health Resources and Services Administration's Uniform Data System for more than 1,100 health centers. We found that in 2012 nine out of ten health centers had adopted a EHR system, and half had adopted EHRs with basic capabilities. Seven in ten health centers reported that their providers were receiving meaningful-use incentive payments from the Centers for Medicare and Medicaid Services (CMS). Only one-third of health centers had EHR systems that could meet CMS's stage 1 meaningful-use core requirements. Health centers that met the stage 1 requirements had more than twice the odds of receiving quality recognition, compared with centers with less than basic EHRs. Policy initiatives should focus assistance on EHR capabilities with slower uptake; connect providers with technical assistance to support implementation; and leverage the connection between meaningful use and quality recognition programs. © 2014 by Project HOPE - The People-to-People Health Foundation. Source


Dubow W.M.,United Information Technology
Computer | Year: 2013

Computing-related jobs are interesting, well-paying, secure, and abundant, so why aren't more women working in this creative field that produces the technology that is central to our daily lives? The Web extra at http://youtu.be/TgNJJzSiBiY is a video interview in which Wendy DuBow, a research scientist at the National Center for Women Information Technology, discusses the importance of gender diversity in computing with Alfred C. (Alf) Weaver, the director of the University of Virginia's Applied Research Institute. © 1970-2012 IEEE. Source

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