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281.
完成了面向信号的ATS软件平台体系结构分析,给出了面向信号的ATS软件平台的定义,详细分析了该软件平台所具有的特征,并在此基础上,借鉴Kruchten的多视图方法,分析了面向信号的ATS软件平台涉及的行为主体,从组织视图、功能视图和信息视图多个视角研究平台的构成与运行方式,最后给出平台的总体模型,并详细介绍了模型中各层的具体定义与功能: 相似文献
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本文根据项目评价的一般原则,结合大飞机项目的特点,建立了大飞机项目的评价指标体系,确立了企业能力、服务程度、合作水平等三项指标,设计了大飞机项目供应商选择的程序和方法,并给出了应用范例。 相似文献
284.
In this article, we study a two‐level lot‐sizing problem with supplier selection (LSS), which is an NP‐hard problem arising in different production planning and supply chain management applications. After presenting various formulations for LSS, and computationally comparing their strengths, we explore the polyhedral structure of one of these formulations. For this formulation, we derive several families of strong valid inequalities, and provide conditions under which they are facet‐defining. We show numerically that incorporating these valid inequalities within a branch‐and‐cut framework leads to significant improvements in computation. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 647–666, 2017 相似文献
285.
We consider scheduling problems involving two agents (agents A and B), each having a set of jobs that compete for the use of a common machine to process their respective jobs. The due dates of the A‐jobs are decision variables, which are determined by using the common (CON) or slack (SLK) due date assignment methods. Each agent wants to minimize a certain performance criterion depending on the completion times of its jobs only. Under each due date assignment method, the criterion of agent A is always the same, namely an integrated criterion consisting of the due date assignment cost and the weighted number of tardy jobs. Several different criteria are considered for agent B, including the maxima of regular functions (associated with each job), the total (weighted) completion time, and the weighted number of tardy jobs. The overall objective is to minimize the performance criterion of agent A, while keeping the objective value of agent B no greater than a given limit. We analyze the computational complexity, and devise polynomial or pseudo‐polynomial dynamic programming algorithms for the considered problems. We also convert, if viable, any of the devised pseudopolynomial dynamic programming algorithms into a fully polynomial‐time approximation scheme. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 416–429, 2016 相似文献
286.
Column generation for stochastic green telecommunication network planning with switchable base stations
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We present the green telecommunication network planning problem with switchable base stations, where the location and configuration of the base stations are optimized, while taking into account uncertainty and variability of demand. The problem is formulated as a two‐stage stochastic program under demand uncertainty with integers in both stages. Since solving the presented problem is computationally challenging, we develop the corresponding Dantzig‐Wolfe reformulation and propose a solution approach based on column generation. Comprehensive computational results are provided for instances of varying characteristics. The results show that the joint location and dynamic switching of base stations leads to significant savings in terms of energy cost. Up to 30% reduction in power consumption cost is achieved while still serving all users. In certain cases, allowing dynamic configurations leads to more installed base stations and higher user coverage, while having lower total energy consumption. The Dantzig‐Wolfe reformulation provides solutions with a tight LP‐gap eliminating the need for a full branch‐and‐price scheme. Furthermore, the proposed column generation solution approach is computationally efficient and outperforms CPLEX on the majority of the tested instances. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 351–366, 2016 相似文献
287.
Branch‐and‐price‐and‐cut for the manpower routing problem with synchronization constraints
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In this article, we propose a branch‐and‐price‐and‐cut (BPC) algorithm to exactly solve the manpower routing problem with synchronization constraints (MRPSC). Compared with the classical vehicle routing problems (VRPs), the defining characteristic of the MRPSC is that multiple workers are required to work together and start at the same time to carry out a job, that is, the routes of the scheduling subjects are dependent. The incorporation of the synchronization constraints increases the difficulty of the MRPSC significantly and makes the existing VRP exact algorithm inapplicable. Although there are many types of valid inequalities for the VRP or its variants, so far we can only adapt the infeasible path elimination inequality and the weak clique inequality to handle the synchronization constraints in our BPC algorithm. The experimental results at the root node of the branch‐and‐bound tree show that the employed inequalities can effectively improve the lower bound of the problem. Compared with ILOG CPLEX, our BPC algorithm managed to find optimal solutions for more test instances within 1 hour. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 138–171, 2016 相似文献
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本文主要阐述了发展电子商务过程中应建立“商务为本”的理念及“商务为本”的理念的含义。 相似文献
290.
本文讨论了大型稀疏线性代数方程组的迭代算法、加速方法、存贮技术及并行算法。结合向量机特点,采取有效程序优化措施,开发研制了标量和向量库程序。在YH系列机上试算结果表明:大型稀疏线性代数向量迭代库比标量迭代库速度有较大提高。当N≥100时,在YH─1机上加速比约2~8;在YH─2机上约2~7;当迭代次数增加时,加速比提高更明显;库中共轭梯度(CG)加速方法能有效地加快收敛,可减少迭代次数一半以上。 相似文献