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1.
Comparison of Four New General Classes of Search Designs   总被引:1,自引:0,他引:1  
A factor screening experiment identifies a few important factors from a large list of factors that potentially influence the response. If a list consists of m factors each at three levels, a design is a subset of all possible 3 m runs. This paper considers the problem of finding designs with small numbers of runs, using the search linear model introduced in Srivastava (1975). The paper presents four new general classes of these 'search designs', each with 2 m −1 runs, which permit, at most, two important factors out of m factors to be searched for and identified. The paper compares the designs for 4 ≤ m ≤ 10, using arithmetic and geometric means of the determinants, traces and maximum characteristic roots of particular matrices. Two of the designs are found to be superior in all six criteria studied. The four designs are identical for m = 3 and this design is an optimal design in the class of all search designs under the six criteria. The four designs are also identical for m = 4 under some row and column permutations.  相似文献   
2.
For a wide variety of applications, experiments are based on units ordered over time or space. Models for these experiments generally may include one or more of: correlations, systematic trends, carryover effects and interference effects. Since the standard optimal block designs may not be efficient in these situations, orthogonal arrays of type I and type II, which were introduced in 1961 by C.R. Rao [Combinatorial arrangements analogous to orthogonal arrays, Sankhya A 23 (1961) 283–286], have been recently used to construct optimal and efficient designs for many of these experiments. Results in this area are unified and the salient features are outlined.  相似文献   
3.
The paper considers simultaneous estimation of finite population means for several strata. A model-based approach is taken, where the covariates in the super-population model are subject to measurement errors. Empirical Bayes (EB) estimators of the strata means are developed and an asymptotic expression for the MSE of the EB estimators is provided. It is shown that the proposed EB estimators are “first order optimal” in the sense of Robbins [1956. An empirical Bayes approach to statistics. In: Proceedings of the Third Berkeley Symposium on Mathematical Statistics and Probability, vol. 1, University of California Press, Berkeley, pp. 157–164], while the regular EB estimators which ignore the measurement error are not.  相似文献   
4.
A K -sample testing problem is studied for multivariate counting processes with time-dependent frailty. Asymptotic distributions and efficiency of a class of non-parametric test statistics are established for certain local alternatives. The concept of efficiency is to show that for every non-parametric test in this class, there is a parametric submodel for which the optimal test has the same asymptotic power as the non-parametric one. The theory is applied to analyse a diabetic retinopathy study data set. A simulation study is also presented to illustrate the theory  相似文献   
5.
儒、释、道三家哲学的共同特正是“无我相”;中国古典诗歌艺术的根本精神也是“无我相”,代表儒释道三家精神的诗人屈原、王维和陶渊明三派诗歌,以艺术手段显现至高无上之境──“物我皆忘”,“物我一体”、在此境界之中,诗歌作为艺术家心灵的外化,绝不是中纯的语言文字对情感的渲泄,而是生命中修炼境界的极致,通达这种“无我”的人格境界和艺术精神,正是中国诗歌艺术的根本精神,  相似文献   
6.
In the binary single constraint Knapsack Problem, denoted KP, we are given a knapsack of fixed capacity c and a set of n items. Each item j, j = 1,...,n, has an associated size or weight wj and a profit pj. The goal is to determine whether or not item j, j = 1,...,n, should be included in the knapsack. The objective is to maximize the total profit without exceeding the capacity c of the knapsack. In this paper, we study the sensitivity of the optimum of the KP to perturbations of either the profit or the weight of an item. We give approximate and exact interval limits for both cases (profit and weight) and propose several polynomial time algorithms able to reach these interval limits. The performance of the proposed algorithms are evaluated on a large number of problem instances.  相似文献   
7.
This paper presents a genetic algorithm (GA) for parallel redundancy optimization in series-parallel power systems exhibiting multi-state behavior, optimizing the reliability subject to constraints. The components are binary and chosen from a list of products available in the market, and are being characterized by their feeding capacity, reliability, cost and weight. System reliability is defined as the ability to satisfy consumer demand and is presented as a piecewise cumulative load curve. In GA, to handle infeasible solutions penalty strategies are used. Penalty technique keep a certain amount of infeasible solutions in each generation so as to enforce genetic search towards an optimal solution from sides of, both, feasible and infeasible regions. We here present a dynamic adaptive penalty function which helps the algorithm to search efficiently for optimal/near optimal solution. To evaluate system reliability, a fast procedure, based on universal generating function, is used. An example considering a multi-state series-parallel power system is solved considering both homogeneous and heterogeneous types of redundancy. Also an example considering price discounts is solved. The effectiveness of the penalty function and the proposed algorithm is studied and shown graphically.  相似文献   
8.
"普世价值"之争在一定程度上给社会思想带来矛盾和困惑,对此,必须坚持唯物史观,科学揭示"普世价值"的实质,为建设我国社会主义核心价值体系营造良好的社会舆论环境。  相似文献   
9.
伴随着中国改革开放的进程,转型成为社会变迁的主题和基本特征。与此相应的却是,改革日益呈现出一种“锁定”的状态。在社会转型时期出现的诸多根本性问题,并不能用过渡性的办法来解决。在国家和法律的现代化进程中,特别是构建法治政府的进程中,政府不能再像过去那样,一味运用相机决策和政策调整来处理社会利益矛盾,不能再对不同群体在基本权利上区别对待。同样,在工农、城乡、区域乃至人与自然生态之间,要实现统筹协调发展的目标,更需要加强普遍性的努力,这种普遍性努力以法治和体现法治精神的整体性政策为特征。  相似文献   
10.
霍桑对普遍的原罪与救赎的独到诠释是源于超越新教伦理的泛基督精神。因而以污点主人公、写情、社会救赎为特点的《红字》所表现的艺术真实具有轰动效应,是推动新教自身改革及美国文艺复兴的重要武器。  相似文献   
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