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151.
文章讨论了"的"后名词短语的主题化过程中要遵循的制约条件,解释了汉语"的"后NP/DP的主题化过程中的不对称现象.并进一步用优选理论讨论了当汉语"的"后NP/DP被指示代词修饰时的主题化现象.由于优选论具有兼容句法、语用等多种因素的优势,可以解释单从句法层面无法解决的难题.  相似文献   
152.
经济学与伦理学有着深刻的内在关联,但是在经济学发展的历程中,经济学抛弃了它的伦理学渊源,逐渐脱离和淡化伦理学的影响,以"自利最大化"为理论前提、以"社会效用"为标准的"帕累托最优"就是在这种背景下产生的.现代经济学家阿玛蒂亚·森对拒绝伦理考虑的"帕累托最优"提出质疑和挑战,并努力在经济学的研究中重新引入价值判断和道德哲学的智慧,在这个基础上提出新的衡量经济发展的标准.  相似文献   
153.
Given a graph G = (V,E), we define the locally optimal independent sets asfollows. Let S be an independent set and T be a subset of V such that S T = and (S) T, where (S) is defined as the neighbor set of S. A minimum dominating set of S in T is defined as TD(S) T such that every vertex of S is adjacent to a vertex inTD(S) and TD(S) has minimum cardinality. An independent setI is called r-locally optimal if it is maximal and there exists noindependent set S V\I with |ID (S)| r such that|S| >|I (S)|.In this paper, we demonstrate that for k-claw free graphs ther-locally optimal independent sets is found in polynomial timeand the worst case is bounded by , where I and I* are a locally optimal and an optimal independent set,respectively. This improves the best published bound by Hochbaum (1983) bynearly a factor of two. The bound is proved by LP duality and complementaryslackness. We provide an efficientO(|V|r+3) algorithm to find an independent set which is notnecessarily r-locally optimal but is guarantteed with the above bound. Wealso present an algorithm to find a r-locally optimal independent set inO(|V|r(k-1)+3) time.  相似文献   
154.
We study an inventory management mechanism that uses two stochastic programs (SPs), the customary one‐period assemble‐to‐order (ATO) model and its relaxation, to conceive control policies for dynamic ATO systems. We introduce a class of ATO systems, those that possess what we call a “chained BOM.” We prove that having a chained BOM is a sufficient condition for both SPs to be convex in the first‐stage decision variables. We show by examples the necessity of the condition. For ATO systems with a chained BOM, our result implies that the optimal integer solutions of the SPs can be found efficiently, and thus expedites the calculation of control parameters. The M system is a representative chained BOM system with two components and three products. We show that in this special case, the SPs can be solved as a one‐stage optimization problem. The allocation policy can also be reduced to simple, intuitive instructions, of which there are four distinct sets, one for each of four different parameter regions. We highlight the need for component reservation in one of these four regions. Our numerical studies demonstrate that achieving asymptotic optimality represents a significant advantage of the SP‐based approach over alternative approaches. Our numerical comparisons also show that outside of the asymptotic regime, the SP‐based approach has a commanding lead over the alternative policies. Our findings indicate that the SP‐based approach is a promising inventory management strategy that warrants further development for more general systems and practical implementations.  相似文献   
155.
The problem of selecting a population according to “selection and ranking” is an important statistical problem. The ideas in selecting the best populations with some demands having optimal criterion have been suggested originally by Bechhofer (1954 Bechhofer, R. E. (1954). A single-sample multiple-decision procedure for ranking means of normal populations with known variances. The Annals of Mathematical Statistics 25:1639. [Google Scholar]) and Gupta (1956 Gupta, S. S. (1956). On a decision rule for a problem in ranking means. Mimeograph Series No. 150. Chapel Hill, North Carolina: University of North Carolina. [Google Scholar], 1965 Gupta, S. S. (1965). On some multiple decision (selection and ranking) rules. Technometrics 7:225245. [Google Scholar]). In the area of ranking and selection, the large part of literature is connected with a single criterion. However, this may not satisfy the experimenter’s demand. We follow methodology of Huang and Lai (1999 Huang, W. T., Lai, Y. T. (1999). Empirical Bayes procedures for selecting the best population with multiple criteria. Annals of the Institute of Statistical Mathematics 51:281299. [Google Scholar]) and the main focus of this article is to select a best population under Type-II progressively censored data for the case of right tail exponential distributions with a bounded and unbounded supports for μi. We formulate the problem and develop a Bayesian setup with two kinds of bounded and unbounded prior for μi. We introduce an empirical Bayes procedure and study the large sample behavior of the proposed rule. It is shown that the proposed empirical Bayes selection rule is asymptotically optimal.  相似文献   
156.
157.
Logistic functions are used in different applications, including biological growth studies and assay data analysis. Locally D-optimal designs for logistic models with three and four parameters are investigated. It is shown that these designs are minimally supported. Efficiencies are computed for equally spaced and uniform designs.  相似文献   
158.
The extant supply chain management literature has not addressed the issue of coordination in supply chains involving risk‐averse agents. We take up this issue and begin with defining a coordinating contract as one that results in a Pareto‐optimal solution acceptable to each agent. Our definition generalizes the standard one in the risk‐neutral case. We then develop coordinating contracts in three specific cases: (i) the supplier is risk neutral and the retailer maximizes his expected profit subject to a downside risk constraint; (ii) the supplier and the retailer each maximizes his own mean‐variance trade‐off; and (iii) the supplier and the retailer each maximizes his own expected utility. Moreover, in case (iii), we show that our contract yields the Nash Bargaining solution. In each case, we show how we can find the set of Pareto‐optimal solutions, and then design a contract to achieve the solutions. We also exhibit a case in which we obtain Pareto‐optimal sharing rules explicitly, and outline a procedure to obtain Pareto‐optimal solutions.  相似文献   
159.
This article is concerned with non-stationary time series which does not require the full knowledge of the likelihood function. Consequently, a quasi-likelihood is employed for estimating parameters instead of the maximum (exact) likelihood. For stationary cases, Wefelmeyer (1996) and Hwang and Basawa (2011a,b), among others, discussed the issue of asymptotic optimality of the quasi-likelihood within a restricted class of estimators. For non-stationary cases, however, the asymptotic optimality property of the quasi-likelihood has not yet been adequately addressed in the literature. This article presents the asymptotic optimal property of the non-stationary quasi-likelihood within certain estimating functions. We use a random norm instead of a constant norm to get limit distributions of estimates. To illustrate main results, the non-stationary ARCH model, branching Markov process, and non-stationary random-coefficient AR process are discussed.  相似文献   
160.
两种语言之间音系和语音的异同可以在外来形式的本族化过程中得以反映。对于汉语中英语外来词的音系调整已有一些文章进行了有见地的描写和分析,但对英语中汉语外来词的音系调整却鲜有阐释。鉴于此,作者尝试性地对英语中汉语外来词辅音的音系调整进行了描写,并在优选论的理论框架下进行了分析。结果表明:英语音段系统对汉语外来形式的音系调整并非是任意的,而是系统的、可预测的。调整过程和结果与英语音系语法中制约条件的等级排列有关。即忠实类制约条件要求最大可能地保留作为输入项的汉语外来形式的特征,而标记类制约条件要求输出项符合英语的音系语法。  相似文献   
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