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201.
This article examines the arms control logic that was applied to the only regional arms control talks that have taken place in the Middle East to date: the Arms Control and Regional Security (ACRS) working group that was part of the multilateral track of the Madrid peace process in the early 1990s. It highlights both the successes and major constraints of the ACRS talks in an effort to assess what might be relevant to the weapons of mass destruction-free zone conference proposed for later this year. In addition to the basic arms control dilemmas that will continue to challenge this conference—as they did ACRS—the article suggests that current conditions in the Middle East are even less conducive to regional dialogue than they were in the earlier period, due to the internal upheavals in several key Arab states, and the specific challenge of Iran's move to develop a military nuclear capability.  相似文献   
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This chapter discusses the impact Provincial Reconstruction Teams (PRTs) have on the security situation in Afghanistan, specifically in countering the terrorist threat and in counter-narcotics.

The Afghan people define the lack of security as their country's greatest problem. The terrorist activities of groups opposed to the central government and the political process compounded by violence related to the opium trade are seen as the main sources of insecurity. The authors argue that, currently, PRTs should not assume active counterterrorism as an additional main area of operation. The complexity of Afghanistan's security environment and the pressure to have PRTs involved in the counter-narcotics effort underscore the necessity of local knowledge and experience in the PRTs. Participation of indigenous actors, such as NGOs, in the PRT-organisational structure could provide this required expertise.  相似文献   
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We present a large‐scale network design model for the outbound supply chain of an automotive company that considers transportation mode selection (road vs. rail) and explicitly models the relationship between lead times and the volume of flow through the nodes of the network. We formulate the problem as a nonlinear zero‐one integer program, reformulate it to obtain a linear integer model, and develop a Lagrangian heuristic for its solution that gives near‐optimal results in reasonable time. We also present scenario analyses that examine the behavior of the supply chain under different parameter settings and the performance of the solution procedures under different experimental conditions. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   
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Nature of Renyi's entropy and associated divergence function is discussed in terms of concave (convex) and pseudoconcave (pseudoconvex) functions.  相似文献   
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An optimization model which is frequently used to assist decision makers in the areas of resource scheduling, planning, and distribution is the minimum cost multiperiod network flow problem. This model describes network structure decision-making problems over time. Such problems arise in the areas of production/distribution systems, economic planning, communication systems, material handling systems, traffic systems, railway systems, building evacuation systems, energy systems, as well as in many others. Although existing network solution techniques are efficient, there are still limitations to the size of problems that can be solved. To date, only a few researchers have taken the multiperiod structure into consideration in devising efficient solution methods. Standard network codes are usually used because of their availability and perceived efficiency. In this paper we discuss the development, implementation, and computational testing of a new technique, the forward network simplex method, for solving linear, minimum cost, multiperiod network flow problems. The forward network simplex method is a forward algorithm which exploits the natural decomposition of multiperiod network problems by limiting its pivoting activity. A forward algorithm is an approach to solving dynamic problems by solving successively longer finite subproblems, terminating when a stopping rule can be invoked or a decision horizon found. Such procedures are available for a large number of special structure models. Here we describe the specialization of the forward simplex method of Aronson, Morton, and Thompson to solving multiperiod network network flow problems. Computational results indicate that both the solution time and pivot count are linear in the number of periods. For standard network optimization codes, which do not exploit the multiperiod structure, the pivot count is linear in the number of periods; however, the solution time is quadratic.  相似文献   
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