带软时间窗的集货与送货多车辆路径问题节约算法

研究了物流配送中多车运输的集货与送货车辆路径规划问题,以增加时间惩罚费用的方式插入软时间窗约束,将租车费用、货车运输费用和时间惩罚费用三者之和最小作为优化目标,建立数学模型。采用启发式节约算法求解该模型,考虑时间惩罚费用和运输费用,比较每一配送节点上直接送货和间接送货的节约费用关系,求出最优配送路径。试验结果表明:当配送次数达到50次时,货车平均装载率仍能达到80%以上,该节约算法能减少货车空程行驶和租车次数,优化了全局费用。     

北京市交通信号管理与控制平台设计及应用

在分析现有交通信号系统的特性以及存在问题的基础上,以对现有信号系统进行有效整合、综合利用交通流数据、提高交通信号控制的管理水平为目标,设计了1种集成的交通信号控制平台,并给出了平台在北京市交通信号管理与控制系统中的应用。     

柴油机电控系统平台开发及应用

介绍了柴油机单体泵电控系统平台化开发内容:ECU硬件开发、上层驱动和应用层开发、底层驱动开发、操作系统及任务调动。提出了V型开发流程、软件CMMI开发方法等规范的开发流程方法。对应用该平台化方法开发的柴油机单体泵电控系统进行试验,验证了该平台开发方法的有效性。     

从欧洲新颁不锈钢管标准看不锈钢管制造技术发展(一)

介绍了2004-2005年欧洲首次颁布的4项不锈钢新标准的总体特点,着重分析了其中有关钢种的化学成分、制造过程和交货条件、质量检验项目和频度选择的灵活性和技术先进性。     

地铁屏蔽门独立组网监视系统

讨论目前地铁采用的几种屏蔽门监控方案.以广州地铁1号线为例,介绍屏蔽门监控独立组网系统.这种屏蔽门系统不需要综合监控系统,独立完成车站间联网,然后在OCC中心设置屏蔽门独立组网服务器来进行中央监控.该系统是屏蔽门独立组网系统在国内的第一次尝试,也是目前国内唯一的一套在运营调度中心(OCC)具备中央监控能力的屏蔽门系统.     

Route design for last-in,first-out deliveries with backhauling

The retail route design problem extends the capacitated vehicle routing problem with time windows by introducing several operational constraints, including order loading and delivery restrictions (last-in, first-out), order-dependent vehicle capacity, material handling limits at the warehouse, backhauling, and driving time bounds. In this paper, the problem is modeled on a directed network for an application associated with a major grocery chain. Because the corresponding mixed-integer program proved too difficult to solve with commercial software for real instances, we developed a greedy randomized adaptive search procedure (GRASP) augmented with tabu search to provide solutions. Testing was done using data sets provided Kroger, the largest grocery chain in the US, and benchmarked against a previously developed column generation algorithm. The results showed that cost reductions of $4887 per day or 5.58% per day on average, compared to Kroger’s corresponding solutions.     

The Share-a-Ride problem with stochastic travel times and stochastic delivery locations

We consider two stochastic variants of the Share-a-Ride problem: one with stochastic travel times and one with stochastic delivery locations. Both variants are formulated as a two-stage stochastic programming model with recourse. The objective is to maximize the expected profit of serving a set of passengers and parcels using a set of homogeneous vehicles. Our solution methodology integrates an adaptive large neighborhood search heuristic and three sampling strategies for the scenario generation (fixed sample size sampling, sample average approximation, and sequential sampling procedure). A computational study is carried out to compare the proposed approaches. The results show that the convergence rate depends on the source of stochasticity in the problem: stochastic delivery locations converge faster than stochastic travel times according to the numerical test. The sample average approximation and the sequential sampling procedure show a similar performance. The performance of the fixed sample size sampling is better compared to the other two approaches. The results suggest that the stochastic information is valuable in real-life and can dramatically improve the performance of a taxi sharing system, compared to deterministic solutions.     

竹胶车箱底板的开发应用

本文介绍了东风汽车公司采用竹胶合板制车箱底板的开发与应用情况，实践证明，作为车箱底材的材料，竹材胶合板的各种性能均优于落叶松板材。     

A cooperative waiting strategy based on elliptical areas for the Dynamic Pickup and Delivery Problem with Time Windows

The purpose of this paper to present a cooperative scheduling algorithm for solving the Dynamic Pickup and Delivery Problem with Time Windows (DPDPTW). The idea behind cooperative waiting strategies is to calculate simultaneously the waiting times for all nodes in the solution. Classical non‐cooperative scheduling algorithms perform the scheduling for each route independently of the scheduling of the other routes. We present the Cooperative Scheduling Problem (CSP) based on the elliptical areas generated by vehicles waiting at their nodes. The CSP is solved by means of a genetic algorithm and is evaluated by using a set of benchmarks based on real‐life data found in the literature. Initially, two waiting strategies are presented: Wait‐Early‐Time scheduling and Balanced‐Departure scheduling. Extensive empirical simulations have been carried out by analyzing the degree of dynamism and the average waiting time, a new concept defined to take into account the gap between the time windows of pickup and delivery nodes. Copyright © 2016 John Wiley & Sons, Ltd.     

无司机列车自动运行系统中屏蔽门的接口设计

以正在建设中的无司机列车自动运行系统为例,从接口界面、接口功能和接口信息等方面深入地介绍了信号系统与屏蔽门系统之间的接口方案,并与常规有司机列车自动运行系统中的接口方案进行比较与分析。