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31.
A learning tabu search for a truck allocation problem with linear and nonlinear cost components 下载免费PDF全文
The two‐level problem studied in this article consists of optimizing the refueling costs of a fleet of locomotives over a railway network. The goal consists of determining: (1) the number of refueling trucks contracted for each yard (truck assignment problem denoted TAP) and (2) the refueling plan of each locomotive (fuel distribution problem denoted FDP). As the FDP can be solved efficiently with existing methods, the focus is put on the TAP only. In a first version of the problem (denoted (P1)), various linear costs (e.g., fuel, fixed cost associated with each refueling, weekly operating costs of trucks) have to be minimized while satisfying a set of constraints (e.g., limited capacities of the locomotives and the trucks). In contrast with the existing literature on this problem, two types of nonlinear cost components will also be considered, based on the following ideas: (1) if several trucks from the same fuel supplier are contracted for the same yard, the supplier is likely to propose discounted prices for that yard (Problem (P2)); (2) if a train stops too often on its route, a penalty is incurred, which represents the dissatisfaction of the clients (Problem (P3)). Even if exact methods based on a mixed integer linear program formulation are available for (P1), they are not appropriate anymore to tackle (P2) and (P3). Various methods are proposed for the TAP: a descent local search, a tabu search, and a learning tabu search (LTS). The latter is a new type of local search algorithm. It involves a learning process relying on a trail system, and it can be applied to any combinatorial optimization problem. Results are reported and discussed for a large set of instances (for (P1), (P2), and (P3)), and show the good performance of LTS. © 2014 Wiley Periodicals, Inc. 62:32–45, 2015 相似文献
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尤靖雯 《武警工程学院学报》2014,(5):17-20
党的十八届三中全会的最大亮点和理论创新之一就是,提出了要实现市场对资源配置的决定性作用。这是思想解放的重大突破,也是深化经济体制改革以及引领其他领域改革的基本方针。阐述了改革开放35年党对市场经济地位和作用认识的历史进程,以及我国社会主义市场经济地位转变的必然性,提出了全面深化经济体制改革、实现市场经济地位转变的举措。 相似文献
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We consider a loss system with a fixed budget for servers. The system owner's problem is choosing the price, and selecting the number and quality of the servers, in order to maximize profits, subject to a budget constraint. We solve the problem with identical and different service rates as well as with preemptive and nonpreemptive policies. In addition, when the policy is preemptive, we prove the following conservation law: the distribution of the total service time for a customer entering the slowest server is hyperexponential with expectation equal to the average service rate independent of the allocation of the capacity. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 81–97, 2015 相似文献
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Kensaku Kikuta 《海军后勤学研究》2004,51(7):977-993
There is a finite cyclic graph. The hider chooses one of all nodes except the specified one, and he hides an (immobile) object there. At the beginning the seeker is at the specified node. After the seeker chooses an ordering of the nodes except the specified one, he examines each nodes in that order until he finds the object, traveling along edges. It costs an amount when he moves from a node to an adjacent one and also when he checks a node. While the hider wishes to maximize the sum of the traveling costs and the examination costs which are required to find the object, the seeker wishes to minimize it. The problem is modeled as a two‐person zero‐sum game. We solve the game when unit costs (traveling cost + examination cost) have geometrical relations depending on nodes. Then we give properties of optimal strategies of both players. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004. 相似文献
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公寓房是我军住房保障体系的重要组成部分,其中又以小户型公寓房为主体,加强小户型公寓的设计研究对提高其保障效能具有现实意义。解读军队公寓住房建筑设计方案竞赛一等奖作品,指出小户型公寓采用一梯两户多层的形式在营造营区环境、降低建筑全寿命费用、改善室内舒适度等方面具有比较优势;应合理分配小户型公寓房面积,适当提高卫浴和厨房所占面积比例,控制客厅和卧室规模;应在门厅空间布局与卫浴空间分室设置、储藏空间多样化、布置多用途小空间、管井集中出户等方面提高设计的精细化程度。 相似文献
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根据研究实际需求,本文基于作战能力评估理论对水下潜器自导搜索策略仿真平台进行了开发设计,并结合建立的多指标评估体系和相应的评估方法,借助均匀设计法,将其成功应用于水下潜器自导搜索策略的设计优化中。文中首先分析了仿真平台的系统需求,进而确定了其总体构架,并针对自导搜索策略研究的特点确定了相应的人机交互界面。最后给出了进行自导搜索策略仿真优化的基本思路和方法,并通过水下潜器最优自导搜索策略方案仿真研究的实例表明,本文设计的仿真平台和研究方法不仅完全能够满足水下潜器的自导搜索策略仿真研究需求,还能有效节省科研成本,具有重要的工程应用价值。 相似文献
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针对由源节点和单个中继节点形成的协同正交频分复用( OFDM) Alamouti空时块码系统,分析了放大前传(AF)模式下的系统容量,给出了解析表达式.考虑节点功率独立约束的应用场景,提出了分步迭代的功率分配算法( SIPAA)来提高系统容量.该算法的核心思想是在每次迭代中,分步对源和中继节点分别进行注水功率分配,注水... 相似文献