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We present an algorithm for solving a specially structured nonlinear integer resource allocation problem. This problem was motivated by a capacity planning study done at a large Health Maintenance Organization in Texas. Specifically, we focus on a class of nonlinear resource allocation problems that involve the minimization of a convex function over one general convex constraint, a set of block diagonal convex constraints, and bounds on the integer variables. The continuous variable problem is also considered. The continuous problem is solved by taking advantage of the structure of the Karush‐Kuhn‐Tucker (KKT) conditions. This method for solving the continuous problem is then incorporated in a branch and bound algorithm to solve the integer problem. Various reoptimization results, multiplier bounding results, and heuristics are used to improve the efficiency of the algorithms. We show how the algorithms can be extended to obtain a globally optimal solution to the nonconvex version of the problem. We further show that the methods can be applied to problems in production planning and financial optimization. Extensive computational testing of the algorithms is reported for a variety of applications on continuous problems with up to 1,000,000 variables and integer problems with up to 1000 variables. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 770–792, 2003. 相似文献
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为了更合理地制定导弹的战术指标和作战任务规划,对多脉冲导弹可达域进行研究。通过引入加权的纵程和横程的组合性能指标函数,将可达域的优化问题转化为最优控制问题,建立以飞行攻角和侧滑角为双优化设计变量的多阶段多约束优化模型,采用hp自适应伪谱法对其进行求解,并着重分析多脉冲导弹发动机参数和终端约束条件对导弹可达域的影响。仿真结果表明,hp自适应伪谱法能有效解决多阶段多约束的多脉冲导弹可达域优化问题,且多脉冲导弹脉冲发动机时间间隔越小,推力比越大,装药比越小,导弹的可达域越大,相比于终端速度对可达域的影响,终端弹道倾角对可达区域的影响较小。 相似文献
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This article describes a polynomial transformation for a class of unit‐demand vehicle routing problems, named node‐balanced routing problems (BRP), where the number of nodes on each route is restricted to be in an interval such that the workload across the routes is balanced. The transformation is general in that it can be applied to single or multiple depot, homogeneous or heterogeneous fleet BRPs, and any combination thereof. At the heart of the procedure lies transforming the BRP into a generalized traveling salesman problem (TSP), which can then be transformed into a TSP. The transformed graph exhibits special properties which can be exploited to significantly reduce the number of arcs, and used to construct a formulation for the resulting TSP that amounts to no more than that of a constrained assignment problem. Computational results on a number of instances are presented. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 370–387, 2015 相似文献
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依据舵减摇状态空间模型,推导舵减横摇广义预测控制律,在舵角舵速约束的条件下,采用二次型规划计算控制量进行减横摇控制.对某一船舶在典型航行工况下进行了系统仿真,仿真结果表明,该方法不但可取得35%~45%的减摇效果,而且对横摇角速度与横摇角加速度也有40%左右的减小效果. 相似文献
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To meet customer demand, delivery companies are offering an increasing number of time‐definite services. In this article, we examine the strategic design of delivery networks which can efficiently provide these services. Because of the high cost of direct connections, we focus on tree‐structured networks. As it may not be possible to identify a tree‐structured network that satisfies all of the delivery guarantees, we allow these guarantees to be violated but seek to minimize the sum of the violations. We establish the complexity of the problem and exploit an empirically identified solution structure to create new neighborhoods which improve solution values over more general neighborhood structures. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献
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This study introduces one modeling methodology that describes a broad range of multiple stage production planning issues, including multiple limited resources with setup times and joint fixed cost relationships. An existing production system is modeled in this fashion, creating a new set of 1350 highly generalized benchmark problems. A computational study is conducted with the 1350 benchmark problems introduced in this paper and 2100 benchmark problems, with more restrictive assumptions, from the existing literature. The relative merits of a decomposition‐based algorithm and a neighborhood search technique known as NIPPA, or the Non‐sequential Incremental Part Period Algorithm, are assessed. NIPPA is generally the more successful of the two techniques, although there are specific instances in which the decomposition‐based algorithm displayed a distinct advantage. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005 相似文献
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李砚超 《中国人民武装警察部队学院学报》2011,(8):21-23
高层建筑火灾具有火灾蔓延途径多、火灾荷载大、扑救难度大等特点,易造成群死群伤的严重后果。在火灾扑救中,主要有举高消防车的高度、出警速度极限、人员疏散与战斗进攻路线、战斗员体能和火场供水等五个方面的限制因素。从实战出发,提出了增强高层建筑火灾灭火救援能力应采取的措施。 相似文献
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This paper focuses on the dynamic tracking control of ammunition manipulator system. A standard state space model for the ammunition manipulator electro-hydraulic system (AMEHS) with inherent non-linearities and uncertainties considered was established. To simultaneously suppress the violation of tracking error constraints and the complexity of differential explosion, a barrier Lyapunov functions-based dynamic surface control (BLF-DSC) method was proposed for the position tracking control of the ammunition manipulator. Theoretical analysis prove the stability of the closed-loop overall system and the tracking error converges to a prescribed neighborhood asymptotically. The effectiveness and dynamic tracking performance of the proposed control strategy is validated via simulation and experi-mental results. 相似文献
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