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991.
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993.
The performance of step-wise group screening In terms of the expected number of runs and the expected number of incorrect decisions, Is considered. A method for obtaining optimal step-wise designs Is presented, for the cases in which the direction of each defective factor is assumed to be known a-priori and the observations are subject to error. 相似文献
994.
Children living in foster care are an especially vulnerable population who often come to the attention of Medicaid mental
health providers. These children experience a high incidence of emotional and behavioral disorders and may have specialized
treatment needs related to their living arrangement status. This study assessed whether Children’s Psychosocial Rehabilitation
could effectively treat youth with severe emotional and behavioral disorders who live in foster care. Analysis of data from
an open trial of 218 clinically-impaired youth, aged 3–18 years, revealed no reliable differences in treatment outcome between
foster versus non-foster children, with a trend toward more favorable outcomes for foster youth. Findings justify further
study of the effectiveness of this Medicaid-funded service for the treatment of youth in care. 相似文献
995.
Stochastic scenario trees are a new and popular method by which surveillance systems can be analyzed to demonstrate freedom from pests and disease. For multiple component systems—such as a combination of a serological survey and systematically collected observations—it can be difficult to represent the complete system in a tree because many branches are required to represent complex conditional relationships. Here we show that many of the branches of some scenario trees have identical outcomes and are therefore redundant. We demonstrate how to prune branches and derive compact representations of scenario trees using matrix algebra and Bayesian belief networks. The Bayesian network representation is particularly useful for calculation and exposition. It therefore provides a firm basis for arguing disease freedom in international forums. 相似文献
996.
J. R. L. Schneider 《Population studies》2013,67(2):148-150
Mr. Silcock's article will be of interest to all concerned with local population data. It may be useful to supplement it by a brief account of the fuller examination of the local population estimates made in 1951 by the General Register Office, since this covered all 1472 administrative areas in England and Wales and could be made in more detail than was possible for a private investigator. Any census, of course, provides information not available, at least in such detail, at other times or from other sources, and also serves as a base from which estimates for succeeding years can be derived. In addition, however, the General Register Office takes the opportunity of a census to try and assess the accuracy of the various types of current population estimates made by the Department. In the case of local administrative areas the comparison of actual and expected populations made after the 1931 Census is discussed in the Text Volume of the Registrar General's Statistical Review for 1930 (pages 100-102). 相似文献
997.
景观设计是一个基于科学的解决规划和设计问题的艺术性行业。本文根据Jon Bryan Burley博士2007年秋在南京林业大学为规划与设计专业师生所作的第七次演讲的内容,阐述了科学与艺术之间的平衡。Burley博士通过展示和列举他在中国工作时个人手绘作品及在密歇根所做的计算机辅助视觉质量评估工作的案例,描述了艺术和科学之间的区别、标准化的理论和科学理论之间的区别。Burley博士认为,作为设计师,艺术和科学两种方法缺一不可。随着科技的发展变化,新方法和新技术终将完美结合并被专业所接受。 相似文献
998.
In this paper we explore the phenomenon of Chinese counterfeits smuggled into Mexico, the world's fourth largest counterfeit market, particularly highlighting the role played by Chinese transnational crime in the production and financing of these illegal exports and the role of the Korean diaspora in the distribution of Chinese counterfeits within Mexico. Based on this case study and the extant literature, we suggest propositions concerning diaspora criminal enterprises and diaspora participants in informal markets that amend current theory concerning two streams of literature — diaspora homeland investment and trade facilitation by diasporas. 相似文献
999.
1000.
Martine T.E. Puts Nastaran Shekary Guy Widdershoven Jeannette Heldens Dorly J.H. Deeg 《Journal of Aging Studies》2009,23(4):258-266
Frailty is a term often used by researchers and clinicians to describe a state in which older persons are at risk for adverse outcomes such as falls, disability, institutionalization and mortality. However, no study so far examined what frailty means to older persons. Therefore the aim of this study was to describe the meaning that older community-dwelling persons attach to frailty. Twenty-five semi-structured interviews were conducted. The interviews were analyzed using the grounded theory method. Frailty was described as being in poor health, having walking difficulties, feeling down, being anxious, having few social contacts and not being able to do the things one likes to do. Men described in more detail the physical dimension whereas women elaborated in more depth on the psychological and social component. Existing definitions of frailty should be adjusted to better reflect the meaning of frailty for older persons. 相似文献