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101.
This paper presents the results of an investigation of the residential search behaviour of owner occupier households in the Belfast Urban Area (BUA). The study area is segregated on the basis of religion. The patterns of religious residential segregation can be traced back almost 200 years, and recent evidence shows that segregation continues to intensify. This suggests that the patterns are supported by contemporary residential decision-making. Whilst residential mobility has been subject to intensive research effort, by comparison the investigation of residential search behaviour has been neglected. The principal focus of this paper is to explore the similarities and differences in behaviour of Catholic and non-Catholic searchers as a first step in developing a better understanding of search in general and the role of religion in particular. The paper finds that Catholic household search differs significantly from that of other households. Interestingly, Catholic household search in Belfast is found to be consistent with minority household search in segregated urban areas of the US.  相似文献   
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The US program for the management and disposal of commercial spent nuclear fuel and high level waste is in a period of potential programmatic, regulatory, and legislative change. Proposals currently being considered by the US Congress would authorize the development of a storage facility as soon as possible adjacent to the potential repository site at Yucca Mountain. The legislation also would establish regulatory requirements for a permanent repository at an individual dose limit of 1 mSv year−1 (100 mrem year−1) for the average person living near the repository. Concurrently, the fiscal year 1996 appropriation to characterize the Yucca Mountain site has been reduced by approximately 40%. These initiatives portend possible changes in the focus of the US program, including a fundamental shift in priority from permanent disposal to temporary storage, and a change in the approach to licensing a potential repository at the Yucca Mountain site. This paper provides the perspective of the members of the Nuclear Waste Technical Review Board on the impact these developments could have on the future of the US program. It discusses the Board's opinion on how to address the issues these and other developments raise in a way which moves the US civilian radioactive waste management program forward.  相似文献   
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Using a large database, this study examined 3 refinements of validity generalization procedures: (1) a more accurate procedure for correcting the residual standard deviation (SD) for range restriction to estimate SDp, (2) use of r? instead of study-observed rs in the formula for sampling error variance, and (3) removal of non-Pearson rs. The 1st procedure does not affect the amount of variance accounted for by artifacts. The addition of the 2nd and 3rd procedures increased the mean percentage of validity variance accounted for by artifacts from 70 to 82%, a 17% increase. The cumulative addition of all 3 procedures decreased the mean SDp estimate from .150 to .106, a 29% decrease. Six additional variance-producing artifacts were identified that could not be corrected for. In light of these it was concluded that the obtained estimates of mean SDp and mean validity variance accounted for were consistent with the hypothesis that the true mean SDp value is close to zero. These findings provide further evidence against the situational specificity hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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We study the problem of approximating one-dimensional nonintegrable codistributions by integrable ones and apply the resulting approximations to approximate feedback linearization of single-input systems. The approach derived in this paper allows a linearizable nonlinear system to be found that is close to the given system in a least-squares (L 2) sense. A linearly controllable single-input affine nonlinear system is feedback linearizable if and only if its characteristic distribution is involutive (hence integrable) or, equivalently, any characteristic one-form (a one-form that annihilates the characteristic distribution) is integrable. We study the problem of finding (least-squares approximate) integrating factors that make a fixed characteristic one-form close to being exact in anL 2 sense. A given one-form can be decomposed into exact and inexact parts using the Hodge decomposition. We derive an upper bound on the size of the inexact part of a scaled characteristic one-form and show that a least-squares integrating factor provides the minimum value for this upper bound. We also consider higher-order approximate integrating factors that scale a nonintegrable one-form in a way that the scaled form is closer to being integrable inL 2 together with some derivatives and derive similar bounds for the inexact part. This allows a linearizable nonlinear system that is close to the given system in a least-squares (L 2) sense together with some derivatives to be found. The Sobolev embedding techniques allow us to obtain an upper bound on the uniform (L ) distance between the nonlinear system and its linearizable approximation. This research was supported in part by NSF under Grant PYI ECS-9396296, by AFOSR under Grant AFOSR F49620-94-1-0183, and by a grant from the Hughes Aircraft Company.  相似文献   
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The 2-process theory of semantic priming (J. H. Neely, 1977; M. I. Posner and C. R. Snyder, 1975) was used to determine the maintenance of automatic processes after severe closed head injury (CHI) and to determine whether processes that demand attention suffer a deficit. Ss with severe CHI (N?=?18,?>?2 yrs postinjury) and 18 matched control Ss completed a lexical decision task in which a category prime was followed by a target. Automatic and attentional priming were determined by orthogonally varying prime–target relatedness, expectancy, and stimulus onset asynchrony. Although the CHI Ss had slower reaction times (RTs) overall, there were no significant group differences in the magnitude of either the automatic or attentional component of semantic priming. The present results indicate the integrity of semantic processes and normal semantic priming in long-term patients with severe CHI. The results are discussed in relation to an attentional resource hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Tested the hypothesis that Ss with severe mental illnesses would achieve better vocational outcomes with an accelerated approach to supported employment (AASE), as compared to gradual approaches (GA) with prevocational training. 86 Ss (mean age 35.1 yrs) with a diagnosis of a serious mental illness, were randomly assigned to either the AASE, or the GA, which included a minimum of 4 mo prevocational training. Data were obtained on indicators of vocational outcomes over 2 yrs, and for a limited number of Ss (n=36), during the 4th yr of inception into the program. Initially, only 5% of Ss preferred prevocational training. After 1 yr, AASE Ss showed better outcomes for a range of indicators, including achievement of competitive employment, duration of employment and mean earnings. During the 4th yr, 59% of these Ss were competitively employed, as compared to only 6% of GA Ss. Rehabilitation is more effective using AASE than GA. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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