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Rankin D.M. Gulliver T.A. Taylor D.P. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2003,49(9):2230-2235
This article investigates the asymptotic performance of single parity-check (SPC) product codes (PCs) from a decoding point of view. Specifically, the probability of bit error is bounded before and after the decoding of each dimension, similar to the analysis of "iterated codes" by Elias (1954). It is shown that the asymptotic probability of bit error can be driven to zero as the number of dimensions, and hence the block length, increases at signal-to-noise ratios (SNRs) within 2 dB of capacity over the additive white Gaussian noise (AWGN) channel. 相似文献
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Thirty patients who had undergone either a right or left unilateral temporal lobectomy (14 RTL; 16 LTL) and 16 control participants were tested on a computerized human analogue of the Morris Water Maze. The procedure was designed to compare allocentric and egocentric spatial memory. In the allocentric condition, participants searched for a target location on the screen, guided by object cues. Between trials, participants had to walk around the screen, which disrupted egocentric memory representation. In the egocentric condition, participants remained in the same position, but the object cues were shifted between searches to prevent them from using allocentric memory. Only the RTL group was impaired on the allocentric condition, and neither the LTL nor RTL group was impaired on additional tests of spatial working memory or spatial manipulation. The results support the notion that the right anterior temporal lobe stores long-term allocentric spatial memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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C Diamond ML Huang DH Kedes C Speck GW Rankin D Ganem RW Coombs TM Rose JN Krieger L Corey 《Canadian Metallurgical Quarterly》1997,176(3):775-777
The prevalence of human herpesvirus 8 (HHV-8)/Kaposi's sarcoma (KS)-associated herpesvirus was investigated in the semen of 99 human immunodeficiency virus (HIV)-infected men (median CD4 cell count, 357/mm3) by use of a polymerase chain reaction (PCR) assay capable of detecting <10 copies of HHV-8 DNA. Of the subjects, 95 (96%) self-identified as men who have sex with men (MSM), and 3 had a history of clinical KS. Seminal cell specimens were negative for HHV-8 in 98 subjects. None of the 26 without KS (27.1% of 96 tested) who were seropositive for HHV-8 by IFA for latency-associated nuclear antigens had HHV-8 detected in their semen. The only subject with any evidence for seminal HHV-8 DNA was seropositive for HHV-8 and had active KS. HHV-8 was detected in 10 (10.4%) of 96 peripheral blood mononuclear cell specimens. The prevalence of HHV-8 DNA by PCR in semen of HIV-infected MSM without KS is low. 相似文献
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Discusses the prevalence of physical and mental disabilities in the US and the extent of the discrimination encountered by the disabled. The purpose and major provisions of the Americans with Disabilities Act are reviewed. Ambiguous areas in the new law that are of concern to psychologists are considered, specifically the disabled status of persons with chemical dependencies and psychological testing in employment settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Jeff H. Rankin & Thomas M. Froese 《Computer-Aided Civil and Infrastructure Engineering》2002,17(4):256-268
This paper discusses the future requirements of integrated construction management systems and the need to support the management of large volumes of information on several levels. The solution proposes a combination of an efficient user interface and methods to partially automate the creation of the required information through access to stored information from past projects. The research follows the path being established for integrated construction management systems that rely on a standard representation of the industry's information requirements. By exploring the comprehensive aspects of construction planning for an integrated construction management system, the research demonstrates the usefulness of applying sound information representation structures. Through the application of case-based reasoning, the research advances the concepts of planning tools as they apply to integrated systems. The resulting prototype construction management system has the primary characteristic of assisting the user in the manipulation of information in order to generate the initial information requirements of an integrated construction management system. 相似文献
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Surveyed the prevalence of weight reducing and weight gaining in 1,373 high school students. 63% of the girls and 16.2% of the boys reported being on weight-reducing regimens; 9.1% of the girls and 28.4% of the boys were trying to gain weight. Most female reducers and male gainers were already normal weight. Whites and Hispanics were more likely to be reducing, whereas Blacks were more likely to be gaining. Exercise and moderate caloric reduction were most popular for weight reducing, and a small but significant number were regularly using fasting, vomiting, laxatives, and appetite suppressants. The rate of weight reducing in female high school adolescents has increased significantly since similar surveys of American youths 20 yrs ago. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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A review of robust design methods for multiple responses 总被引:1,自引:0,他引:1
Terrence E. Murphy Kwok-Leung Tsui Janet K. Allen 《Research in Engineering Design》2005,16(3):118-132
Problems in engineering design often involve determining design variable settings to optimize individual product performance
for multiple criteria, which are often in conflict. We review mathematically rigorous techniques from the statistical literature
for finding a vector x of design variable settings, which produces an optimal compromise solution among a group of prioritized response variables.
The best compromise solution is typically gained by optimizing an objective function, which incorporates the prioritized demands
of multiple responses. Since most multi-response objective functions are constructed by combining the functions used to optimize
univariate responses, a review of the prominent univariate approaches is presented first. A multivariate approach from the
engineering literature called the compromise Decision Support Problem is also reviewed. Finally a table comparing the relative
merits of the different multivariate approaches summarizes the article in a concise and user-friendly fashion. 相似文献