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81.
This paper considers a new class of scheduling problems arising in logistics systems in which two different transportation modes are available at the stage of product delivery. The mode with the shorter transportation time charges a higher cost. Each job ordered by the customer is first processed in the manufacturing facility and then transported to the customer. There is a due date for each job to arrive to the customer. Our approach integrates the machine scheduling problem in the manufacturing stage with the transportation mode selection problem in the delivery stage to achieve the global maximum benefit. In addition to studying the NP‐hard special case in which no tardy job is allowed, we consider in detail the problem when minimizing the sum of the total transportation cost and the total weighted tardiness cost is the objective. We provide a branch and bound algorithm with two different lower bounds. The effectiveness of the two lower bounds is discussed and compared. We also provide a mathematical model that is solvable by CPLEX. Computational results show that our branch and bound algorithm is more efficient than CPLEX. © 2005 Wiley Periodicals, Inc. Naval Research Logistics, 2005 相似文献
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基于支持多级业务的单码CDMA系统 ,本文设计了一种适合于多级业务接入的两层控制方案。借助于该方案 ,实时业务用户一旦被接纳就立刻进行通信。而非实时数据用户的通信过程要受到呼叫层和突发层双重的控制。这样 ,前者的QoS能够得到保证 ,而后者则可以充分利用网络暂时闲置的信道容量。 相似文献
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刘用权 《装甲兵工程学院学报》1995,(3)
根据装备综合保障大纲要求达到的目的和所要完成的任务,提出了装备综合保障军用标准的体系表,建议并拟定了“大纲”的框架结构. 相似文献
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舰艇保障是一种主要依赖后勤技术装备的专业化后勤,也是涉及并行、冲突,并受资源、装配时间等限制的复杂离散事件过程。借助定时Petri网强大的描述能力标记过程中的各种动态行为,在此基础上对包括后勤装备在内的后勤实体、保障任务、保障活动等进行建模,采用编码、转换等手段实现舰艇保障过程仿真,并使用仿真结果对后勤保障能力进行"定量计算"为主的分析评估。 相似文献
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军事虚拟仓库的结构分析 总被引:4,自引:2,他引:2
军事虚拟仓库可以有效改进我国当前军事仓库物资储备机制,健全储备结构,优化储备布局,提高储备效率。研究军事虚拟仓库对于促进军事物流的发展具有重要意义。对军事虚拟仓库的概念及作用进行了简单介绍,分析了其主要特点,并对军事虚拟仓库的信息网络结构、功能结构以及组织结构进行了研究。 相似文献
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Palestinian uprising, ‘intifada’, aggravated the recession of 2001–2004 in Israel which dampened demand for labor in all industries except security services. We use this exogenous shock to study whether a cohort of young men who were attached to temporary jobs as security guards for unusually long periods of time during the intifada landed on an inferior career path, as compared to security guards from a pre-intifada cohort. We find that the intifada cohort had less employment mobility, were ultimately less connected with the labor market, and earned less on jobs after the security services, relatively to the pre-intifada cohort. 相似文献
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运输装备保障效能评估是军交运输系统优化的基础。构建了运输装备效能评估指标体系,提出了指标标准化和定性指标定量化的思路和方法,建立了不同条件下设计保障效能和瞬时保障效能评估模型。这些模型不仅具有很强的适用性,而且为成系统成建制装备的整体保障效能评估奠定了基础。 相似文献
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2019年年底,一场突如其来的新型冠状病毒肺炎疫情在全国爆发,中华民族的复兴之路和中国人民的幸福生活都面临着严峻的考验和挑战。这次疫情使人们对公共卫生突发事件有了更清醒的认识,完善重大疫情应急响应机制成为今后公共安全必须加强的一项重要工作。此次的公共卫生事件具有显著的突发性、广泛性和群体性,与战时后勤保障环境具有相似性,为深入研究后勤保障工作提供了经典的现实案例。本文借鉴抗击疫情经验教训分析军队后勤保障工作,结合大数据、物联网和人工智能等高新技术实践经验,从后勤指挥、战场感知、物资配送和网络通信等多个方面提出新时代后勤保障建设的思路和方法,对未来加强新时代后勤保障工作具有一定的借鉴及参考意义。 相似文献