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针对维修专业不同的设置模式和运行模式,对多专业流水式批量维修任务调度问题进行了分析和建模,在考虑任务权重的基础上将该问题分成两步求解。首先,建立了初始专业领域内批量维修任务调度及优化模型;其次,建立了考虑任务权重的多专业流水式批量维修任务调度模型。实例验证表明:该方法更贴近于实际,可快速、有效地解决批量维修任务调度问题。 相似文献
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以灭火救援技术与战术课程作业为切入点,分析了作业存在的主要问题,提出了作业内容优化方案,结合问卷调查法分析了学员对课后作业优化前、后的满意程度,并提出可行的应用策略。 相似文献
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灰色局势决策理论在炮兵火力计划优选中的运用 总被引:1,自引:0,他引:1
为了解决炮兵火力计划选择的随意性和盲目性,提出了以灰色理论为基础,综合考虑炮兵火力计划的性质和拟制原则的优选方法;深入研究了局势决策在计划优选中的应用;最后举例说明了灰色局势决策理论在计划优选中的应用,进一步证明了其科学性和创新性,为优选决策提供了一种定量和定性相结合的新方法。 相似文献
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Express package carrier networks have large numbers of heavily‐interconnected and tightly‐constrained resources, making the planning process difficult. A decision made in one area of the network can impact virtually any other area as well. Mathematical programming therefore seems like a logical approach to solving such problems, taking into account all of these interactions. The tight time windows and nonlinear cost functions of these systems, however, often make traditional approaches such as multicommodity flow formulations intractable. This is due to both the large number of constraints and the weakness of the linear programming (LP) relaxations arising in these formulations. To overcome these obstacles, we propose a model in which variables represent combinations of loads and their corresponding routings, rather than assigning individual loads to individual arcs in the network. In doing so, we incorporate much of the problem complexity implicitly within the variable definition, rather than explicitly within the constraints. This approach enables us to linearize the cost structure, strengthen the LP relaxation of the formulation, and drastically reduce the number of constraints. In addition, it greatly facilitates the inclusion of other stages of the (typically decomposed) planning process. We show how the use of templates, in place of traditional delayed column generation, allows us to identify promising candidate variables, ensuring high‐quality solutions in reasonable run times while also enabling the inclusion of additional operational considerations that would be difficult if not impossible to capture in a traditional approach. Computational results are presented using data from a major international package carrier. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献
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The optimization framework for optimal sensor placement for underwater threat detection has been developed. It considers single‐period and multiperiod detection models, each of which includes two components: detection algorithm and optimization problem for sensor placement. The detection algorithms for single‐period and multiperiod models are based on likelihood ratio and sequential testing, respectively. For the both models, the optimization problems use the principle of superadditive coverage, which is closely related to energy‐based and information‐based approaches. An algorithm for quasi‐regular sensor placement approximating solutions to the optimization problems has been developed based on corresponding continuous relaxations and a criterion for its applicability has been obtained. Numerical experiments have demonstrated that the algorithm consistently outperforms existing optimization techniques for optimal sensor placement.© 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献
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