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Erdem Eskigun Reha Uzsoy Paul V. Preckel George Beaujon Subramanian Krishnan Jeffrey D. Tew 《海军后勤学研究》2007,54(3):282-300
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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Motivated by some practical applications, we study a new integrated loading and transportation scheduling problem. Given a set of jobs, a single crane is available to load jobs, one by one, onto semitrailers with a given capacity. Loaded semitrailers are assigned to tractors for transportation tasks. Subject to limited resources (crane, semitrailers, and tractors), the problem is to determine (1) an assignment of jobs to semitrailers for loading tasks, (2) a sequence for the crane to load jobs onto semitrailers, (3) an assignment of loaded semitrailers to tractors for transportation tasks, and (4) a transportation schedule of assigned tractors such that the completion time of the last transportation task is minimized. We first formulate the problem as a mixed integer linear programming model (MILPM) and prove that the problem is strongly NP‐hard. Then, optimality properties are provided which are useful in establishing an improved MILPM and designing solution algorithms. We develop a constructive heuristic, two LP‐based heuristics, and a recovering beam search heuristic to solve this problem. An improved procedure for solutions by heuristics is also presented. Furthermore, two branch‐and‐bound (B&B) algorithms with two different lower bounds are developed to solve the problem to optimality. Finally, computational experiments using both real data and randomly generated data demonstrate that our heuristics are highly efficient and effective. In terms of computational time and the number of instances solved to optimality in a time limit, the B&B algorithms are better than solving the MILPM. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 416–433, 2015 相似文献
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Christopher Clary 《战略研究杂志》2019,42(5):677-700
ABSTRACTThis article examines decision-making mistakes made by U.S. President Nixon and national security advisor Kissinger during the 1971 India-Pakistan crisis and war. It shows that Nixon and Kissinger routinely demonstrated psychological biases that led them to overestimate the likelihood of West Pakistani victory against Bengali rebels as well as the importance of the crisis to broader U.S. policy. The evidence fails to support Nixon and Kissinger’s own framing of the 1971 crisis as a contest between cool-headed realpolitik and idealistic humanitarianism, and instead shows that Kissinger and Nixon’s policy decisions harmed their stated goals because of repeated decision-making errors. 相似文献
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仝倩倩 《兵团教育学院学报》2016,(4):62-66
当前中学英语语法教学仍采用传统的教学方法,从而忽视了学生学习主体性、经验性和能动性。本研究提出将启发式教学方法运用于中学英语语法课堂教学实践之中,并通过建构中学英语启发式教学的5阶段,即预备阶段、提示阶段、联想阶段、统合阶段及应用阶段,试图激发学生积极参与教学活动意识,促进师生及生生间的互动,提高英语语法课堂教学质量。 相似文献
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In this paper the problem of minimizing makespan in a two‐machine openshop is examined. A heuristic algorithm is proposed, and its worst case performance ratio and complexity are analyzed. The average case performance is evaluated using an empirical study. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 129–145, 1999 相似文献
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针对D-S证据理论在高冲突下失效的问题,在比较修正原始证据源和重新分配冲突两种方法的基础上,提出一种新的合成规则,新方法用可信度修正证据的同时,把全局冲突分为两部分,并依据"全局冲突在全局分配、局部冲突在局部分配"的原则对冲突进行细化分配。通过仿真分析,并与其他方法比较,新的合成方法能更好地融合冲突证据,收敛速度快,具有较强的抗干扰能力。 相似文献
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向达 《中国人民武装警察部队学院学报》2010,(11):47-51
孔子和苏格拉底分别被誉为东西方的伦理学之父,作为轴心时代的文化英雄,他们的思想言行对后世产生了巨大的影响,例如孔子对中国重史、伦理本位及注入式教学等的影响,苏格拉底对西方理性、平等、自由及启发式教学的影响等。在当下时代,东西方文化都遇到了较大的困境,需要在碰撞与融合中获得新生。 相似文献