供应链运输与库存整合优化技术应用分析

文章指出,运输与库存是物流配送过程中的两个关键环节,这两个环节的整合优化是供应链管理研究的前沿课题.运输与库存的整合优化是指,在满足给定的产品需求及运输限定条件下,同时寻求最优的库存与运输配送策略,使供应链系统运输与库存的总费用达到最小的最优化技术或方法.运输与库存整合优化应着重解决四个问题:一是确定最优库存水平;二是确定补货频率及补货时刻;三是确定所需车辆数量及配送区域;四是确定运输线路.进而实现对运输与库存问题的联合统筹决策,最低化运输与库存总成本.文章提出,尽管目前运输与库存整合优化问题研究还面临许多困难(如抽象出具有特定应用背景的实际问题并运用恰当的数学优化模型进行全面而准确的描述,然后用可行算法求解等),但随着先进库存管理模式在我国的广泛应用及市场供应链竞争的不断加剧,对运输调度与库存决策整合优化技术进行研究将变得越来越迫切,其广泛应用也将成为必然趋势.     

The hidden value of air transportation infrastructure

Air transportation is a key strategic asset in that it provides access to markets and thereby enables the economic development of nations. Thus, in order to maintain their competitiveness in a global economy, countries must invest in air transportation infrastructure to ensure their ability to meet current and future demand for aviation services. The objective of this paper is to develop and illustrate a methodology for evaluating the strategic value of air transportation infrastructure, in particular the benefits associated with the ability to react quickly to changes in the market. The hypothesis is that by recognizing and taking advantage of this strategic value, it may be possible to design better policies for aviation infrastructure delivery.The methodology developed here uses system dynamics to model different strategies for infrastructure delivery. These strategies are defined by three variables: the amount of capacity increase, the time to deliver the capacity and the congestion threshold that triggers the need for capacity delivery. Monte Carlo simulation is used to take into account multiple sources of uncertainty. The model shows that a strategy of capacity delivery based on small increments and short response times can yield more benefits than strategies that consider large capacity increases and long response times. Furthermore, in the specific airport example considered here, it was found that a congestion threshold of 75% should be the trigger for capacity enlargements if strategies based on small capacity increments and 1 or 5 years to increase capacity are considered. The lesson for decision-makers is that congestion delays must be addressed with foresight.     

交通基础设施投资对经济增长推动作用研究——基于中国省级面板数据分析

本文依据生产函数模型和我国1994-2007年度30个省级地区(重庆市包含在四川省内)面板数据分析交通基础设施投资对我国各省份经济增长推动作用,得出在规模报酬不变条件下,我国各省份交通基础设施投资产出系数,进而得出经济越发达地区,交通基础设施投资对于经济增长贡献越大的结论。     

加强信息化战争军事交通运输能力建设

随着科学技术的飞速发展,信息化已经成为这个时代的显著特征之一。而信息化战争也必将成为未来战争中的主要形式之一。为适应新军事变革的需要,加快我军信息化的建设已刻不容缓,而信息化条件下军事交通运输能力的建设就成为摆在我们面前的一个极为紧迫而又重大的课题。     

运输定价的基本理论及其比较分析

详细介绍了运输成本导向定价论、运输需求导向定价论和运输竞争导向定价论各自包含的特色定价方法及定价依据,指明它们分别主要以运输成本、运输需求和市场竞争作为定价的依据,可以说各有利弊。通过对各种定价理论的比较分析,指出在实际应用中,更多应考虑三种定价理论的有机结合。     

优化物流运营效率下的交通运输规划模式探究

在前人研究的基础之上,对优化物流运营效率下的交通运输规划模式做了大体的介绍,分析了我国现阶段物流交通运输规划模式,指出其不足之处,然后对优化物流运营效率下的交通运输规划模式做出展望。     

联盟运输调度的煤炭运输运作模式的研究

首先对煤炭运输现状进行分析,并对煤炭运输的几种形式的优缺点进行比较,然后通过对联盟运输调度问题研究,分析并提出了四种联盟的合作模式,最后采用联盟运输调度的煤炭运输运作模式进行分析。     

Numerical and analytical results for the transportation problem of Monge-Kantorovich

The Monge-Kantorovich transportation problem has a long and interesting history and has found a great variety of applications (see Rachev and Rüschendorf (1998a,b)). Some interesting characterizations of optimal solutions to the transportation problem (resp. coupling problems) have been found recently. For the squared distance and discrete distributions they relate optimal solutions to generalized Voronoi diagrams. Numerically we investigate the dependence of optimal couplings on variations of the coupling function. Numerical results confirm also a conjecture on optimal couplings in the one-dimensional case for nonconvex coupling functions. A proof of this conjecture is given under some technical conditions. Received: November 1999     

校企协同共建高职智能交通综合实训基地的实践

实训基地建设是高职高技能人才培养的基础和保障。以智能交通广东省级实训基地建设为例,按照统筹规划、校企合作、工学结合、资源共享、注重效益的原则,从建设依据、建设目标与思路、建设举措、建设效果等方面进行了探讨,校企合作建设了校内智能交通高技能人才培养基地、智能交通服务与培训平台和校外多岗位轮换车间课堂实训基地,将智能交通实训基地建设成为集教学、培训、职业技能鉴定和技术应用与服务为一体的多功能平台,探索了高职实训基地建设新模式。     

ZY5000/15/32掩护式液压支架的优化设计

当支架工作一定时间后出井维护时,需要将前梁与顶梁之间的销轴拿掉后改为运输销轴连接,由于井底空间、设备有限,操作极为不便;另外,由于前梁千斤顶是靠销轴受力,因为支架工作时间比较长且井下环境恶劣,导致销轴出现变形、生锈等现象,以致销轴不易拆卸。