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91.
No abstract available for this article.  相似文献   
92.
Summary

The concepts of D-, A- and E-minimax optimality criteria of designs for estimating the slopes of a response surface are considered for situations where the region of interest may not be identical to the experimental region. Optimal second-order designs are derived for the situation where the experimental region and the region of interest are both hyperspherical with a common centre. The dependence of the optimal design on the relative sizes of the regions is investigated. Further, the perfomance of designs optimal for one region in estimating slopes in other regions is also examined.  相似文献   
93.
Sensitivity analysis of air scattered neutron dose at several distances from a particle accelerator with respect to shield thickness and neutron yield distributions has been carried out. We illustrate the successful use of Response Surface Methodology in studying the behaviour of the sensitivity coefficients for main effects and interaction terms. A comparison of the full six factor design and the orthogonal Central Composite Design has been made. The overhead shield is found to be the most sensitive parameter followed by the high energy part of the neutron energy distribution.  相似文献   
94.
95.
Abstract

The issue of behavioral covariation has been a topic of interest to behavior analysts for many years. Many writers have used the term response generalization interchangeably with behavioral covariation. In this paper, we argue from the extant literature that the term “response generalization” should be used to describe only very specific occasions of behavioral covariation. In fact, we argue, response generalization is merely one of at least six types of behavioral covariation observed in organizational behavior management studies. After describing response generalization, the remaining five types of response-response relations we describe are: (1) physiological relations, (2) when target behaviors occasion related behaviors, (3) when target behaviors reinforce related behaviors, (4) when target and related behaviors are maintained by the same reinforcing stimulus, and (5) covariation through participation in verbal relations. We conclude by discussing the potential for additional research on this topic in the area of verbal relations.  相似文献   
96.
Through a Personal Emergency Link system, the Senior Citizen Home Safety Association has rendered 24-hour care to more than 111,000 service users in Hong Kong who are mostly vulnerable seniors and chronic invalids living alone or living with their elderly spouses/caregivers only. This article will describe how the Personal Emergency Link system is used to link seniors living in the community. Measures taken to prevent failure of the system will be described. With the use of different technology applications, many human touches and warm caregiving are rendered to the elderly and needy.  相似文献   
97.
对川东T构造须家河组含气储层的地球物理响应特征进行了分析,采用地质与地球物理互馈结合的手段,通过合成记录正演、储层置换的方法进行了其地质形成机制研究。结果表明:T构造须家河组含气储层主要表现为低频率、弱振幅(近空白)反射,其形成机制主要有两方面的因素,一是含气层速度的降低导致振幅减弱,在薄层叠加效应的作用下,含气层下部出现弱振幅;二是含气层对高频的吸收作用,低频率导致砂泥岩互层无法分辨,表现为弱振幅。最终形成的低频率、弱振幅特征是这两种因素的综合响应,该特征在T构造高部位可以作为识别含气储层的标志。  相似文献   
98.
Response surface methodology is widely used for developing, improving, and optimizing processes in various fields. In this article, we present a method for constructing three-level designs in order to explore and optimize response surfaces combining orthogonal arrays and covering arrays in a particular manner. The produced designs achieve the properties of rotatability, predictive performance and efficiency for the estimation of a second-order model.  相似文献   
99.
Quality of life (QOL) has become an important component of health. By using the methodology of psychometric theory, we examine the item properties of the WHOQOL-BRIEF. Samejima’s graded response model with natural metrics of the logistic response function was fitted. The results showed items with negative natures were less discriminating. Items written in a specific way were more suitable to assess certain subgroups. The national items showed variation in discriminatory power. Questions measuring objective and specific issues performed worse than items assessing general aspects of the QOL.  相似文献   
100.
Severe departures from normality occur frequently for null distributions of statistics associated with applications of mulLi-response permutation procedures (MRPP) for either small or large finite populations. This paper describes the commonly encountered situation associated with asymptotic non-normality for null distributions of MRPP statistics which does not depend on the underlying multivariate distribution. In addition, this paper establishes the existence of a non-degenerate underlying distribution for which the null distributions of MRPP statistics are asymptotically non-normal for essentially all size structure configurations. It is known that MRPP statistics are symmetric versions of a broader class of statistics, most of which are asymmetric. Because of the non-normality associated with null distributions of MRPP statistics, this paper includes necessary results for inferences based on the exact first three moments of anv statistic in this broader class (analogous to existing results for MRPP statistics).  相似文献   
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