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961.
This article focuses on decision sciences research in China, providing an overview of current research and developing a foundation for future China‐based research. China provides a unique research opportunity for decision sciences researchers, owing to its recent history, rapid economic development, and strong national culture. We examine recent economic reforms and their impact on the development of research questions in the decision sciences, as well as discuss characteristics of the diverse regions in China and their potential as sites for various types of research. We provide a brief overview of recent China‐based research on decision sciences issues relating to national culture, supply chain management, quality management, production planning and control, operations strategy, and new product development and discuss some of the unique methodological challenges inherent in China‐based research. We conclude by looking forward to emerging research opportunities in China.  相似文献   
962.
Manufacturers often face a choice of whether to recover the value in their end‐of‐life products through remanufacturing. In many cases, firms choose not to remanufacture, as they are (rightly) concerned that the remanufactured product will cannibalize sales of the higher‐margin new product. However, such a strategy may backfire for manufacturers operating in industries where their end‐of‐life products (cell phones, tires, computers, automotive parts, etc.) are attractive to third‐party remanufacturers, who may seriously cannibalize sales of the original manufacturer. In this paper, we develop models to support a manufacturer's recovery strategy in the face of a competitive threat on the remanufactured product market. We first analyze the competition between new and remanufactured products produced by a monopolist manufacturer and identify conditions under which the firm would choose not to remanufacture its products. We then characterize the potential profit loss due to external remanufacturing competition and analyze two entry‐deterrent strategies: remanufacturing and preemptive collection. We find that a firm may choose to remanufacture or preemptively collect its used products to deter entry, even when the firm would not have chosen to do so under a pure monopoly environment. Finally, we discuss conditions under which each strategy is more beneficial.  相似文献   
963.
We explore the value of information (VOI) in the context of a firm that faces uncertainty with respect to demand, product return, and product recovery (yield). The operational decision of interest in matching supply with demand is the quantity of new product to order. Our objective is to evaluate the VOI from reducing one or more types of uncertainties, where value is measured by the reduction in total expected holding and shortage costs. We start with a single period model with normally distributed demands and returns, and restrict the analysis to the value of full information (VOFI) on one or more types of uncertainty. We develop estimators that are predictive of the value and sensitivity of (combinations of) different information types. We find that there is no dominance in value amongst the different types of information, and that there is an additional pay‐off from investing in more than one type. We then extend our analysis to the multi‐period case, where returns in a period are correlated with demands in the previous period, and study the value of partial information (VOPI) as well as full information. We demonstrate that our results from the single period model (adapted for VOPI) carry‐over exactly. Furthermore, a comparison with uniformly distributed demand and return show that these results are robust with respect to distributional assumptions.  相似文献   
964.
This article examines the degree of autonomy of Hong Kong’s Airport Authority (AA). Traditionally, airport management in Hong Kong was the responsibility of the government’s Civil Aviation Department. The AA was established in 1995 to manage the new international airport at Chek Lap Kok which opened in 1998. It was expected to run as a commercial enterprise but, because of its strategic importance, there was concern that it should not become an independent empire detached from government control. As a hybrid type of organization, the AA has moved steadily towards full commercialization. The government has also put its privatization on the agenda. Its transformation may have some implications for the redefinition of the future autonomy boundaries of public corporations in Hong Kong.
  相似文献   
965.
Consider the problem of partitioning n nonnegative numbers into p parts, where part i can be assigned ni numbers with ni lying in a given range. The goal is to maximize a Schur convex function F whose ith argument is the sum of numbers assigned to part i. The shape of a partition is the vector consisting of the sizes of its parts, further, a shape (without referring to a particular partition) is a vector of nonnegative integers (n1,..., np) which sum to n. A partition is called size-consecutive if there is a ranking of the parts which is consistent with their sizes, and all elements in a higher-ranked part exceed all elements in the lower-ranked part. We demonstrate that one can restrict attention to size-consecutive partitions with shapes that are nonmajorized, we study these shapes, bound their numbers and develop algorithms to enumerate them. Our study extends the analysis of a previous paper by Hwang and Rothblum which discussed the above problem assuming the existence of a majorizing shape. This research is partially supported by ROC National Science grant NSC 92-2115-M-009-014.  相似文献   
966.
The syntenic distance between two genomes is the minimum number of fusions, fissions, and translocations that can transform one genome to the other, ignoring the gene order within chromosomes. As the problem is NP-hard in general, some particular classes of synteny instances, such as linear synteny, exact synteny and nested synteny, are examined in the literature. In this paper, we propose a new special class of synteny instances, called uncovering synteny. We first present a polynomial time algorithm to solve the connected case of uncovering synteny optimally. By performing only intra-component moves, we then solve the unconnected case of uncovering synteny. We will further calculate the diameters of connected and unconnected uncovering synteny, respectively.  相似文献   
967.
The Web proxy location problem in general networks is an NP-hard problem. In this paper, we study the problem in networks showing a general tree of rings topology. We improve the results of the tree case in literature and get an exact algorithm with time complexity O(nhk), where n is the number of nodes in the tree, h is the height of the tree (the server is in the root of the tree), and k is the number of web proxies to be placed in the net. For the case of networks with a general tree of rings topology we present an exact algorithm with O(kn 2) time complexity.This research has been supported by NSF of China (No. 10371028) and the Educational Department grant of Zhejiang Province (No. 20030622).  相似文献   
968.
网上交易中诚信交易激励机制设计   总被引:1,自引:0,他引:1       下载免费PDF全文
网上交易中日益增长的欺诈行为阻碍了人们参与网上交易的积极性.激励参与方在网上交易中诚信交易非常必要,而现有的简单反馈机制难以实现激励诚信交易的功能.提出了一种新的网上交易市场中激励诚信交易的机制——注册押金和交易保证金制度.该机制不仅把交易前的交易保证金与交易方信誉指数结合起来防范交易方欺诈,而且重构了每次交易可获得的信誉指数计算方法以激励交易方在长期中保持诚信.通过对该机制下交易方行为的博弈分析,证明了诚信不仅是单阶段博弈的纳什均衡策略,还是长期博弈的子博弈完美纳什均衡策略.最后,通过随机选取eBay市场的交易数据,对机制进行了模拟,并验证了其有效性.  相似文献   
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