编辑部关于发表“国家中长期交通运输规划摘要”的决定——国家《中长期铁路网规划》内容简介

交通运输事关国民经济发展和百姓生活的最基本需求．与中国经济的成长一样，我国交通运输业也历经了从传统的计划经济向市场经济转型的过程．作为国民经济发展的基础，和其他行业相比，交通运输具有准公共特性．为真正将国家意志体现到交通运输能力供给中，遵循本届政府决策，建设项目“规划先行”的原则，国家发展和改革委员会会同铁道部、交通部等有关单位，按照全面建设小康社会宏伟目标的要求，以科学发展观为指导，在充分考虑我国土地、人口等资源分布的基础上，将交通运输发展规划理论与交通发展实践相结合，组织编制了《中长期铁路网规划》、《高速公路网规划》、《农村公路建设规划》、《长江三角洲、珠江三角洲、渤海湾三区域沿海港口建设规划（2004年-2010年）》和《环渤海京津冀地区、长江三角洲地区、珠江三角洲地区城际轨道交通网规划》，现已完成并正式颁布实施．上述5项规划从不同层面反映了国家交通资源的空间布局与国家生产力布局的结合，国家综合交通体系发展方向和重点；体现了在市场经济条件下，如何结合中国的具体实际充分发挥各种运输方式的技术经济优势，做好运输资源的配置，并更加突出了效率与公平．对于加快我国铁路与高速公路的发展，促进综合交通网络的形成，加速区域现代综合运输体系建设，全面增强运输普遍服务能力，提升综合交通的生产力水平和服务水平，都具有十分重要的指导作用．     

Air cargo operations: Literature review and comparison with practices

This study reviews the literature on air cargo operations and compares theoretical studies with the practical problems of airlines, freight forwarders, and terminal service providers. In particular, we review studies in which mathematical models were used to identify the essential characteristics of air cargo operations, such as the intrinsic differences from passenger operations, and to explore the service processes in air cargo operations. The typical models used in previous studies are summarized. We then highlight the insightful findings from an industrial interview and present the gaps between previous research and practical realities. We finally discuss the new research opportunities of air cargo operations according to the gaps.     

刚架拱桥的加固及施工方案探讨

通过对徐州市贾汪区省道252线塔山桥的现场调查,并进行静动载实验,分析该桥病害产生的成因,提出合理的加固方案及相应的施工方法,可为加固同类旧桥提供参考。     

On the existence of stationary states in general road networks

Our daily driving experience and empirical observations suggest that traffic patterns in a road network are relatively stationary during peak periods. In numerous transportation network studies, there has been an implicit conjecture that stationary states exist in a network when origin demands, route choice proportions, and destination supplies are constant. In this study, we first rigorously formulate the conjecture within the framework of a network kinematic wave theory with an invariant junction model. After defining stationary states, we derive a system of algebraic equations in 3-tuples of stationary link flow-rates, demands, and supplies. We then introduce a new definition of junction critical demand levels based on effective demands and supplies. With a map in critical demand levels, we show that its fixed points and, therefore, stationary states exist with the help of Brouwer’s fixed point theorem. For two simple road networks, we show that the map is well-defined and can be used to solve stationary states with a brute-force method. Finally we summarize the study and present some future extensions and applications.     

Dynamic charging infrastructure deployment for plug-in hybrid electric trucks

Inspired by the rapid development of charging-while-driving (CWD) technology, plans are ongoing in government agencies worldwide for the development of electrified road freight transportation systems through the deployment of dynamic charging lanes. This en route method for the charging of plug-in hybrid electric trucks is expected to supplement the more conventional charging technique, thus enabling significant reduction in fossil fuel consumption and pollutant emission from road freight transportation. In this study, we investigated the optimal deployment of dynamic charging lanes for plug-in hybrid electric trucks. First, we developed a multi-class multi-criteria user equilibrium model of the route choice behaviors of truck and passenger car drivers and the resultant equilibrium flow distributions. Considering that the developed user equilibrium model may have non-unique flow distributions, a robust deployment of dynamic charging lanes that optimizes the system performance under the worst-case flow distributions was targeted. The problem was formulated as a generalized semi-infinite min-max program, and a heuristic algorithm for solving it was proposed. This paper includes numerical examples that were used to demonstrate the application of the developed models and solution algorithms.     

论员工的绩效薪酬与正向激励

谋求最高劳动生产率是科学管理的根本目的,为了充分调动员工创造价值的主动性和积极性,绩效薪酬管理的重要性在企业管理中日益凸显。为了最大限度地激发员工积极性,科学、可行、合理、公正的绩效考核是有效的管理手段和管理模式。但目前,在相当多的企业中,绩效考核并未达到预期效果,不合理的考核方案甚至可能激起劳资双方的对立情绪或引发员工之间的不当竞争。本文针对此类情况,分析普遍存在的问题并提出了优化对策及非物质激励的改进方案。     

电气化铁路混合宽频滤波器研究

为解决电气化铁路中交-直型和交-直-交型电力机车混跑产生的3~100次宽频谐波问题,提出采用由无源部分和有源部分构成的混合宽频滤波器(Hybrid Wideband-harmonics Filter,HWF)。通过对HWF拓扑结构、滤波原理及滤波特性、有源部分承受电压情况、谐波补偿系数对HWF补偿特性的影响和稳定性进行分析,研究HWF控制策略,并进行仿真和试验验证。结果表明:HWF对宽频谐波具有良好的滤波效果,能够很好地抑制无源部分阻抗与电网阻抗之间的谐振;基波谐振电路能减小有源部分的基波电压,使其适用于中高压电力系统;谐波补偿系数取值越大,HWF对谐波的抑制能力越强。仿真和试验结果验证了HWF的有效性。     

浅谈氢燃料电池电动汽车布置设计

本文结合作者实际工作经验,介绍了某氢燃料电池电动汽车的电堆及其附件系统的布置设计,包括空气供应系统、氢气供应系统和电堆热管理系统,积累经验,供后来者参考。     

铁路现代物流营销模式的发展目标和实现机制研究——以铁路钢铁供应链为例

铁路现代物流必须实现从过去单个运输职能向组成供应链的多元素职能转换。集成化策略是供应链发展的最高层次,通过成员企业之间的协同合作,对供应链上、下游企业的整体集成可以为客户创造低成本高效能的最大化价值。"多""快""好""省"应当是包括铁路钢铁供应链在内的所有供应链集成化目标,也是以供应链理论为基础的铁路现代物流营销模式的发展目标。     

A Football Field Lost Every 45 Minutes: Evaluating Local Capacity to Implement Louisiana's Coastal Master Plan

As Louisiana continues to experience substantial coastal wetland loss—at the rate of a football field every 45 min—and multiple disasters, state and federal officials struggle with implementing restoration plans in this highly productive ecosystem. The 2007 Louisiana Comprehensive Master Plan for a Sustainable Coast is the first large-scale restoration plan in the United States to incorporate hazard mitigation. However, there is no mandate for local governments to adhere to this plan. Building upon the planning quality and evaluation literature, this study analyzes comprehensive land use plans in Louisiana's coastal zone to systematically assess the quality of the plans within the context of a non-mandated, $50 billion large-scale state restoration plan. Results indicate a great disparity in plan quality; a majority of the local governments lack the capacity to implement the nonstructural programmatic elements of the state's plan. The study concludes with a discussion and recommendations for practice and future research.