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韩耀东 《辽宁省交通高等专科学校学报》2012,14(2):39-43
结合实际工作经验与长期研究结果,总结了工程物流的概念与四大基本特点:指出受国际工程承包业务的显著增长,工程物流的国际化即国际工程物流成为新的发展趋势.进而系统分析了国际工程物流的市场前景、业务流程与框架、关键要素等运营方面的关键问题,最后以实际案例形式对关键要素进行了剖析。 相似文献
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针对北京市地铁5号线天通苑北站P+R停车场规模与实际停车换乘需求不匹配的问题,研究确定其停车换乘需求的预测方法,并提出解决停车设施供给不足的方案。在分析天通苑地区P+R停车场时间、车辆来源及设施供给情况的基础上,建立Logit随机均衡交通方式选择模型,得到该地区高峰小时停车换乘需求量为1476个泊位。同时,将预测结果与天通苑北站P+R停车场实际可扩展停车规模进行比较,提出在瓶颈路段设置新的P+R停车场的方案,并建立了系统优化平衡模型,对该地区的停车换乘需求进行分配。结果表明,新建P+R停车场规模分别为300,400,500和600个泊位的条件下,停车换乘需求基本按照两个停车场的规模比例分配停车数量。 相似文献
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基于ITIL的物流企业信息系统运维改进探究 总被引:1,自引:0,他引:1
本文以铁路物流企业中铁快运为例,在对信息系统运维管理实施过程中应用ITIL及IT服务管理的理论,构建信息系统集中运行管理平台,对提高IT系统运维效率和管理水平做了尝试. 相似文献
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Modeling and Analysis of Logistics System Based on Stochastic Petri Net under Supply Chain Circumstances 总被引:1,自引:0,他引:1
In order to describe the impacts of adjustment ability of logistics system on the profit and cost of logistics system, we constructed a model of logistics system based on stochastic Petri net (SPN), and proposed a theorem for the adjustment ability of logistics system under supply chain circumstances on condition that the payoff of supply chain is a steadily increasing process. Then we put forward that a sequence of MGF (moment generating function) of out-of-goods risk process for logistics system is a martingale. The model we proposed can overcome shortcomings of the previous ones that can not describe the characteristics of the adjustment ability of logistics system. The results of simulation experiments are consistent with theoretical analysis. 相似文献
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Electric vehicles (EVs) are considered as a feasible alternative to traditional vehicles. Few studies have addressed the impacts of policies supporting EVs in urban freight transport. To cast light on this topic, we established a framework combining an optimization model with economic analysis to determine the optimal behavior of an individual delivery service provider company and social impacts (e.g., externalities and welfare) in response to policies designed to support EVs, such as purchase subsidy, limited access (zone fee) to congestion/low-emission zones with exemptions for EVs, and vehicle taxes with exemptions for EVs. Numerical experiments showed that the zone fee can increase the company’s total logistics costs but improve the social welfare. It greatly reduced the external cost inside the congestion/low-emission zone with a high population, dense pollution, and heavy traffic. The vehicle taxes and subsidy were found to have the same influence on the company and society, although they have different effects with low tax/subsidy rates because their different effects on vehicle routing plans. Finally, we performed a sensitivity analysis. Local factors at the company and city levels (e.g., types of vehicle and transport network) are also important to designing efficient policies for urban logistics that support EVs. 相似文献
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There are no studies that model the potential effectiveness of Unmanned Aerial Vehicles (UAVs) or drones to reduce CO2e lifecycle (including both utilization and vehicle phase) emissions when compared to conventional diesel vans, electric trucks, electric vans, and tricycles. This study presents a novel analysis of lifecycle UAV and ground commercial vehicles CO2e emissions. Different route and customer configurations are modeled analytically. Utilizing real-word data, tradeoffs and comparative advantages of UAVs are discussed. Breakeven points for operational emissions are obtained and the results clearly indicate that UAVs are more CO2e efficient, for small payloads, than conventional diesel vans in a per-distance basis. Drastically different results are obtained when customers can be grouped in a delivery route. UAV deliveries are not more CO2e efficient than tricycle or electric van delivery services if a few customers can be grouped in a route. Vehicle phase CO2e emissions for UAVs are significant and must be taken into account. Ground vehicles are more efficient when comparing vehicles production and disposal emissions per delivery. 相似文献
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In the considered automated container terminal (ACT) that is designed for Shanghai Yangsha Terminal, two automated stacking cranes (ASCs) are configured for each block and they interact with automated lifting vehicles (ALVs) at the two ends of a block individually. To increase the capacity, container yards with multiple rows of blocks perpendicular to the terminal’s shoreline are considered. To utilize the yard spaces, the twin ASCs are devised to share the same tracks installed at the two sides of a block, while interferences between the ASCs challenge the routing and sequencing operations. To isolate the control and simplify the coordination of the two ASCs, the interference between ASCs is formulated by analyzing the minimal temporal intervals between any two tasks. Three models are then established to sequence the container handling tasks under the minimization of the makespan. An exact algorithm and a genetic algorithm are designed to solve the problem. Numerical experiments show that the algorithms are competitive comparing to on-the-shelf solvers. Practical implications are investigated based on the formulations and experimental results. The managerial implications and technological aspects of applying the formulations and algorithms to practical situations to real-world ACTs are discussed. 相似文献
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通过分析国内外冷藏运输的发展变化过程及其影响要素,探寻冷藏运输的发展规律,分析食品冷链物流及其关键技术在我国的应用发展状况,研究我国铁路参与并发展冷链物流服务的模式和方法。 相似文献