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221.
We consider a problem of scheduling jobs on m parallel machines. The machines are dedicated, i.e., for each job the processing machine is known in advance. We mainly concentrate on the model in which at any time there is one unit of an additional resource. Any job may be assigned the resource and this reduces its processing time. A job that is given the resource uses it at each time of its processing. No two jobs are allowed to use the resource simultaneously. The objective is to minimize the makespan. We prove that the two‐machine problem is NP‐hard in the ordinary sense, describe a pseudopolynomial dynamic programming algorithm and convert it into an FPTAS. For the problem with an arbitrary number of machines we present an algorithm with a worst‐case ratio close to 3/2, and close to 3, if a job can be given several units of the resource. For the problem with a fixed number of machines we give a PTAS. Virtually all algorithms rely on a certain variant of the linear knapsack problem (maximization, minimization, multiple‐choice, bicriteria). © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008  相似文献   
222.
We extend the noncooperative game associated with the cost spanning tree problem introduced by Bergantiños and Lorenzo (Math Method Oper Res 59(2004), 393–403) to situations where agents have budget restrictions. We study the Nash equilibria, subgame perfect Nash equilibria, and strong Nash equilibria of this game. © 2008 Wiley Periodicals, Inc. Naval Research Logistics 2008  相似文献   
223.
匈牙利算法在多目标分配中的应用   总被引:9,自引:1,他引:8  
在多目标攻击决策中 ,根据 Harold提出的目标优势函数 ,分析了使所有目标机的总优势函数为指派问题 ,运用匈牙利算法对 n对 n的最优目标分配指派问题进行求解 ,并把它推广至 n对 m的多目标分配中。仿真结果表明匈牙利算法对于此类多目标分配指派问题的求解是十分有效的。  相似文献   
224.
就业与社会稳定的正相关:就业的保障功能的发挥、激励功能的发挥、融入功能的发挥、协作功能的发挥,都有助于实现社会稳定。就业存在的问题与社会稳定的负相关:失业人员大量存在、就业弱势群体大量存在、就业权益缺失,都影响着社会稳定。  相似文献   
225.
针对近年来对一些建筑消防设施水系统工程的中期检查和工程消防验收.以及对投入使用后的建筑进行消防监督检查中发现的建筑消防设施水系统工程存在的一些施工质量问题,在依据有关消防技术性规范的基础上,查找根源,提出几点建议。  相似文献   
226.
联合国维和警察是一个特殊的职业群体,所处的工作和生活环境艰苦、恶劣、危险。维和警察面对这种超出常规的精神压力,出现各种各样的心理问题是必然的。维和警察的心理问题仅仅依靠维和警察个人自我调节是远远不够的,必须建立一套有效的调控机制来预防和治疗其心理问题,维护好他们的心理健康。  相似文献   
227.
近年来,随着我国堵截、打击毒品犯罪力度的持续加大,境内外贩毒集团组织实施大宗毒品贩运的能力明显减弱,毒品犯罪快速蔓延的势头得到初步遏制。但是,贩毒集团为逃避打击、降低风险,不断变换犯罪手法,钻法律漏洞,特别是组织、利用特殊人群进行贩毒活动的现象日益增多,并呈现出家族化、规模化的趋势,而公安机关在打击特殊群体贩毒活动中,由于立法和执法等多方面的原因,还面临法律、查缉、羁押、案件处理等一系列的问题。执法实践要求运用法律、经济、行政、教育、文化等措施,综合治理特殊群体贩毒问题,努力从源头上遏制特殊人群贩毒问题的滋生、蔓延。  相似文献   
228.
本文通过教师的信念、课堂教学、教师的问题意识三个方面的探讨,来论述教师对数学学业不良生的影响,希望通过教师的作用有效促进数学学业不良生的转化。  相似文献   
229.
We consider the problem of determining the capacity to assign to each arc in a given network, subject to uncertainty in the supply and/or demand of each node. This design problem underlies many real‐world applications, such as the design of power transmission and telecommunications networks. We first consider the case where a set of supply/demand scenarios are provided, and we must determine the minimum‐cost set of arc capacities such that a feasible flow exists for each scenario. We briefly review existing theoretical approaches to solving this problem and explore implementation strategies to reduce run times. With this as a foundation, our primary focus is on a chance‐constrained version of the problem in which α% of the scenarios must be feasible under the chosen capacity, where α is a user‐defined parameter and the specific scenarios to be satisfied are not predetermined. We describe an algorithm which utilizes a separation routine for identifying violated cut‐sets which can solve the problem to optimality, and we present computational results. We also present a novel greedy algorithm, our primary contribution, which can be used to solve for a high quality heuristic solution. We present computational analysis to evaluate the performance of our proposed approaches. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 236–246, 2016  相似文献   
230.
The warehouse problem with deterministic production cost, selling prices, and demand was introduced in the 1950s and there is a renewed interest recently due to its applications in energy storage and arbitrage. In this paper, we consider two extensions of the warehouse problem and develop efficient computational algorithms for finding their optimal solutions. First, we consider a model where the firm can invest in capacity expansion projects for the warehouse while simultaneously making production and sales decisions in each period. We show that this problem can be solved with a computational complexity that is linear in the product of the length of the planning horizon and the number of capacity expansion projects. We then consider a problem in which the firm can invest to improve production cost efficiency while simultaneously making production and sales decisions in each period. The resulting optimization problem is non‐convex with integer decision variables. We show that, under some mild conditions on the cost data, the problem can be solved in linear computational time. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 367–373, 2016  相似文献   
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