集成化物流管理中库存路径问题研究综述

综合国内外多种参考文献,介绍了IRP的基本概念及其主要特征,从常见模型、求解策略及算法2个维度综述了当前国内外关于IRP的主要研究进展,最后指出了该研究领域在未来研究中应予以重视的几个研究方向,为进一步的研究奠定了基础.     

运力受扰的多车场车辆调度干扰管理问题研究

为解决物流配送系统中因运输车辆毁坏而产生的干扰问题,基于干扰管理思想提出了解决问题的扰动恢复策略与实施方案。在扰动度量的基础上,设计了多车场车辆调度扰动恢复策略,建立相应的干扰管理模型。针对多车场车辆调度干扰管理问题的特有属性,设计了一系列求解简化策略,有效简化了问题的求解空间。结合干扰管理模型的特点,使用改进的遗传算法进行求解。最后给出了一个算例,其结果证明了干扰管理模型与算法的有效性。     

稀疏Ad hoc网络中路由算法的改进

针对现有Epidemic路由协议及其特点进行了研究．分析了请求定位技术并将其引入到Epdemic协议中．改进后的新协议通过记录历史路由信息,对传输数据定位接收,限制了数据的洪泛范围．仿真结果表明,新协议在数据到达率与资源消耗上有了较大改善．     

北京机动车环境外部成本的测算

针对噪声污染、大气污染、气候变化、土地资源占用等4种主要机动车环境污染,通过定量方法测度2006-2014年北京市机动车的环境外部成本。结果表明:机动车环境污染代价不仅受实际污染量、剂量暴露率等因素影响,还受当地疾病成本、人均收入、碳税价格和心理预期费用等机会成本因素约束,不同的成本体系测算出来的污染代价差异显著。以北京当地成本为例,2006年起北京机动车环境总代价有缓慢上升趋势,年平均增长6.7%,其中空气污染占比最大。环境总代价占当年GDP的比重平均约为0.56%,但污染的相对代价有所减少,且呈现下降趋势。机动车限制政策对环境污染影响有正面的影响效果,2012年以后这种效果逐步减弱。在此基础上,在政策层面认为应通过技术手段,改善机动车尾气污染;增加降噪设备,规范行为;加强重污染天气的预报等综合性手段,以控制机动车的外部性污染问题。     

Scheduling material handling vehicles in a container terminal

Increasing global trade has created the need for efficient container ports. The goal of the port is to move containers as quickly as possible and at the least possible cost. Goods that are delayed at the port are inevitably tardy when delivered to the customer, and thus sanctioned by late charges. Two key activities in the port are (i) unloading of containers from truck and then storage in the export area, and (ii) removal of containers from import storage and then loading onto the trucks. Since containers are large and heavy, specialized material handling vehicles are required for transporting them within the terminal. The focus of this paper is on port terminals where straddle carriers are primarily used to move containers. Container terminals typically have well developed computer and communication networks. Through these networks a terminal scheduler will control and schedule the movement of the straddle carrier fleet in real time. The objective of the terminal scheduler is to minimize the empty travel of straddle carriers, while at the same time minimizing any delays in servicing customers. This paper presents a straddle scheduling procedure that can be used by a terminal scheduler to control the movement of straddle carriers. At its core, the procedure is driven by an assignment algorithm that dynamically matches straddle carriers and trucks, as each becomes available. The procedures were developed and tested in collaboration with the largest container terminal operator in the Port of New York and New Jersey. Using a simulation model of the real system, the superiority of the proposed procedure over two alternative scheduling strategies is illustrated.     

A multi-compartment vehicle routing problem arising in the collection of olive oil in Tunisia

We introduce, model and solve to optimality a rich multi-product, multi-period and multi-compartment vehicle routing problem with a required compartment cleaning activity. This real-life application arises in the olive oil collection process in Tunisia, where regional collection offices dispose of a fleet of vehicles to collect one or several grades of olive oil from a set of producers. For each grade, the quantity offered by a producer changes dynamically over the planning horizon. We first provide a mathematical formulation of the problem, along with a set of known and new valid inequalities. We then propose an exact branch-and-cut algorithm to solve the problem. We evaluate the performance of the algorithm on real data sets under different transportation scenarios to demonstrate to our industrial partner the advantages of using multi-compartment vehicles.     

Supply vessel planning under cost,environment and robustness considerations

Offshore oil and gas installations need reliable cargo deliveries. The vessels supplying these installations on a periodic basis are expensive and constitute a source of emissions of greenhouse gases. Incorporating vessel speed optimization into the supply vessel planning process may significantly reduce fuel consumption and hence emissions. In addition, speed optimization may yield cost reductions if the number of vessels used does not increase. A main uncertainty factor, especially in the winter season, is the weather conditions which impact sailing and service times. Cost minimization and the application of speed optimization strategies may have implications on the robustness of weekly supply vessel schedules since idle times in the schedules are reduced. We develop a simulation-optimization based methodology that considers costs, emissions and robustness in the generation of weekly supply vessel schedules. Results of analyses conducted on real instances show that robustness requirements may yield both increased emissions and costs in the winter season. However, depending on instance characteristics, different degrees of robustness can be incorporated with both costs and emissions reductions through speed optimization.     

广西北部湾经济区产业发展模式与路径选择思考

合理的产业布局对于广西北部湾经济区的建设至关重要。通过对广西北部湾经济区三大产业发展模式和发展路径进行分析，研究表明，第一产业发展模式是农业产业化模式、农业家庭专业化生产模式；第二产业发展模式是生态工业园模式和港城互动模式；第三产业发展模式是金融业与经济协同发展模式、港口物流与经济协同发展模式、旅游业与经济协同发展模式；理想的路径选择是有效整合产业发展与产业布局、有效整合产业发展与对外贸易结构。     

新的Adhoc网络安全路由协议

针对目前Adhoc网络安全DSR协议的安全性难以保证的现状,提出并证明了能够抵御active-1-y(y≥1)攻击的安全DSR所必须满足的一个充要条件,同时设计了一种新的安全DSR协议——ESDSR,并证明该协议满足上述充要条件。分析结果表明,与现有各种安全DSR协议相比,ESDSR不仅达到了抵御active-1-y攻击的安全目标,而且具有最低的资源开销,适用于Adhoc网络环境。     

关于《牵规》中计算传动效率的分析

本文系统分析了引用计算传动效率作为设计参数导致车辆计算制动能力与实际严重脱节的问题,提出用纯制动率作为车辆制动能力的设计参数的建议。