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11.
公路班线客运集约化改革的难点在于利益关系的协调。在广泛调研和深入访谈的基础上,结合班线客运发展历程及现状,从利益分析的视角剖析了政府、企业、个体之间的利益诉求、利益冲突及利益博弈的内在机理,指出挂靠关系下企业与个体之间的利益争夺是集约化发展难以推进的根源。研究提出以当前利益分配格局为均衡点的“实收配股”集约化发展改革方案,同时强调政府应转变职能定位、完善相关政策,防止形成市场封锁或垄断。 相似文献
12.
The purpose of this paper is to document the extent to which Brazilian companies in retail channels have committed to adopting environmental sustainability measures, goals and strategies for waste disposal in the evaluation and planning of sustainable transportation. This paper also aims to examine the different viewpoints of sustainability issues and the preventive actions taken by companies in terms of controlling carbon dioxide emissions and proper disposal of tires, lubricant oils, accessories and spare parts. Finally, taking the perspective of these companies, this paper examines their difficulties in meeting environmental regulations. The research involved a survey completed by 185 representatives of different types of companies, including shippers (represented by manufacturers), LSPs (logistics service providers) and carriers. The non-linear canonical correlation was calculated to verify the opinions of these representatives from different companies regarding issues that impact on the environment, the preventive actions they adopt to reduce their environmental impact and their difficulties in meeting environmental regulations. The results show that shippers and LSPs have the same perceptions regarding these sustainability issues and preventive actions. In addition, the companies perceive high costs and the lack of training for their partners as the major challenges experienced in addressing these issues and undertaking preventive actions. Therefore they need to plan their transportation activities. 相似文献
13.
联运企业的效益受运输路径和运输方式的影响。如何降低联运成本、提高联运企业的效益,已成为学术研究的重中之重。针对集装箱公铁联运路径优化问题,以运输成本、换装成本、储存成本、时间惩罚成本构成的运输总成本为目标函数,建立集装箱公铁联运路径优化模型,考虑运输时间限制、班期限制、节点储存成本,得出使运输总成本最低的运输路径及运输方式,并利用算例验证模型的有效性。 相似文献
14.
《Omega》2015
Offshore petroleum industry uses helicopters to transport the employees to and from installations. Takeoff and landing represent a substantial part of the flight risks for passengers. In this paper, we propose and analyze approaches to create a safe flight schedule to perform pickup of employees by several independent flights. Two scenarios are considered. Under the non-split scenario, exactly one visit is allowed to each installation. Under the split scenario, the pickup demand of an installation can be split between several flights. Interesting links between our problem and other problems of combinatorial optimization, e.g., parallel machine scheduling and bin-packing are established. We provide worst-case analysis of the performance of some of our algorithms and report the results of computational experiments conducted on randomly generated instances based on the real sets of installations in the oil fields on the Norwegian continental shelf. This paper is the first attempt to handle takeoff and landing risk in a flight schedule that consists of several flights and lays ground for the study on more advanced and practically relevant models. 相似文献
15.
铁路整车货运运价率结构对于货运整体收入及市场竞争力具有重要影响。通过对国家铁路货运总体运营价格水平与整车运价率、整车运价率基价1与基价2之间比价关系的分析发现,整车货运比价关系存在的主要问题体现在运价号设置的结构性、对运输成本的抵补、价率水平的均衡性以及与货物品类的对应关系等方面。因此,提出在"一口价"模式下充分考虑运输市场竞争因素、适当调整各运价号基价1与基价2增幅及比值关系、增设新运价号以及与运价浮动管理相结合充分利用3号运价等调整建议。 相似文献
16.
中美铁路行业治理制度及其效率的比较分析 总被引:1,自引:0,他引:1
本文从铁路行业治理的视角,以铁路企业间的相互依赖性及其行业内协调制度为分析对象,分析中美铁路行业治理制度环境的相似性与差异性,探讨中美铁路行业内协调的制度安排的细节及其差异性,并运用比较制度分析的理论研究中美铁路行业内运营协调的信息体制及其效率差异,分析其清算制度的不同激励效果与适应性差异,阐述其对中国铁路重组的启示。 相似文献
17.
通过对中国各运输方式现状的研究,论述物流与运输的互动发展关系,提出发展中国综合运输系统的相关建议和设想。 相似文献
18.
大宗物资集中采购的调运计划研究 总被引:3,自引:1,他引:3
大宗物资调运问题是一个受多因素影响的复杂问题,一般来讲,其调运数量大、地域跨度大、时间紧。如何协调供需以及运输能力,保证物资采购部门的经济利益是本文所要研究的问题。本文首先给出了大宗物资集中采购的调运模式,然后针对采购部门在大宗物资调运过程中遇到的困难,为采购部门提出了以获取数量折扣、准时采购、降低库存成本和协调运输能力为准则的调运计划模型。数值计算表明应用本文所建模型编制调运计划能够达到降低采购费用、协调运输能力的目的,为大宗物资调运计划的编制提供了一种较为有效的方法。 相似文献
19.
Eric Specking Bobby Cottam Gregory Parnell Edward Pohl Matthew Cilli Randy Buchanan Zephan Wade Colin Small 《Risk analysis》2019,39(9):1899-1912
Recently, efforts to model and assess a system's resilience to disruptions due to environmental and adversarial threats have increased substantially. Researchers have investigated resilience in many disciplines, including sociology, psychology, computer networks, and engineering systems, to name a few. When assessing engineering system resilience, the resilience assessment typically considers a single performance measure, a disruption, a loss of performance, the time required to recover, or a combination of these elements. We define and use a resilient engineered system definition that separates system resilience into platform and mission resilience. Most complex systems have multiple performance measures; this research proposes using multiple objective decision analysis to assess system resilience for systems with multiple performance measures using two distinct methods. The first method quantifies platform resilience and includes resilience and other “ilities” directly in the value hierarchy, while the second method quantifies mission resilience and uses the “ilities” in the calculation of the expected mission performance for every performance measure in the value hierarchy. We illustrate the mission resilience method using a transportation systems‐of‐systems network with varying levels of resilience due to the level of connectivity and autonomy of the vehicles and platform resilience by using a notional military example. Our analysis found that it is necessary to quantify performance in context with specific mission(s) and scenario(s) under specific threat(s) and then use modeling and simulation to help determine the resilience of a system for a given set of conditions. The example demonstrates how incorporating system mission resilience can improve performance for some performance measures while negatively affecting others. 相似文献
20.
新世纪城市交通发展态势及其影响——以南京市为例 总被引:1,自引:1,他引:0
以南京市为例 ,就决定大城市未来交通结构与模式的三种关键交通方式———小汽车、自行车、公共交通的发展前景、态势及其影响进行分析研究 ,以期为制定跨世纪的城市交通发展战略与政策提供依据 相似文献