车体材质对城轨车辆运行阻力的影响

介绍了铝合金、不锈钢和耐候钢等三种车体材质对车体质量及城轨车辆运行阻力的影响。     

薄壁箱梁剪滞剪切效应自振特性分析

在推导考虑剪力滞、剪切变形双重效应的单元刚度矩阵与等效结点荷载矩阵的基础上[1],进一步推导出考虑双重效应的单元质量矩阵,从而形成完整的薄壁箱梁考虑双重效应的矩阵分析体系,可方便地纳入矩阵位移法程序系统,为常见的薄壁连续梁等复杂结构的剪力滞效应分析提供一种计算手段。利用自编程序ZLBOX对薄壁箱型简支梁和悬臂梁考虑剪力滞、剪切变形双重效应时的自振特性进行了分析,所得结果与ANSYS实体单元计算结果符合良好。计算结果表明,剪力滞、剪切变形双重效应使薄壁箱梁的自振频率降低,剪力滞效应占双重效应的85%以上,双重效应对高阶频率的影响比低阶频率的影响大。     

城市轨道交通智能综合监控系统设计

研究目的：城市轨道交通监控系统是运营阶段管理工作的核心，其监控范围的广度和深度直接影响轨道交通运营质量。目前国内的监控系统，关键设备和技术大都从国外全盘引进，很不经济，也造成了隐患。实现监控系统国产化势在必行。 研究方法：本文在分析国内外城市轨道交通运营安全现状的基础上，提出了利用通信、计算机控制技术和人工智能技术，建立城市轨道智能运输系统的基本构想，并进一步提出城市轨道交通智能综合监控系统的设计框架。分析该综合监控系统的内涵、逻辑框架、结构信息流、物理框架和接口技术。 研究结果：跟现有的监控系统相比，智能综合监控系统具有监测范围广、分工明确、实现集中化管理、一体化协调运作和智能化管理的特点，充分体现了以人为本的理念。 研究结论：对于今后国内的城市轨道交通监控系统的建设具有科学的指导意义。     

Estimation of origin‐destination matrices for a multimodal public transit network

This paper presents a procedure for the estimation of origin‐destination (O‐D) matrices for a multimodal public transit network. The system consists of a number of favored public transit modes that are obtained from a modal split process in a traditional four‐step transportation model. The demand of each favored mode is assigned to the multimodal network, which is comprised of a set of connected links of different public transit modes. An entropy maximization procedure is proposed to simultaneously estimate the O‐D demand matrices of all favored modes, which are consistent with target data sets such as the boarding counts and line segment flows that are observed directly in the network. A case study of the Hong Kong multimodal transit network is used to demonstrate the effectiveness of the proposed methodology.     

Structural Characteristics and Mechanical Properties of Rock Mass in the Field of Tianwan Nuclear Power Plant, China

Introduction The project of Tianwan Nuclear Power Plant,located in Pashan, at the south foot of HouyuntaiMount, northeast of Lianyungang City, JiangsuProvince, is entitled State Key Project in collabo-ration with Russia. This project is carried out atthree phases, with two reactors to be built at eachphase. Important constructions such as the nuclearislets and the normal islets are all situated at thebedrock zone. With regard to the field study of thenuclear power plant, the authors have…     

城市轨道交通通信系统集中维护的实施方案

本文就当今城市轨道交通建设中较为先进的通信系统集中管理模式,介绍了轨道交通中通信系统进行集中统一维护管理的实施方案,以及与轨道交通中其它系统的维护接口问题,仅供参考。     

浅谈轨道交通数据网的建设

分析了轨道交通单独组建数据网的必要性,并从从数据网传输技术的选则,网络的拓扑结构、节点设备的选择、网络的可靠性和 QoS 实现手段等方面阐述轨道交通数据网络的设计思路。     

城轨首都国际机场线CBTC信号系统

结合工程项目实际，对首都国际机场线采用的CBTC（基于通信的列车控制）信号系统进行介绍。     

Subsidy and public transit performance: A factor analytic approach

The need to measure and evaluate transit system performance has led to the development of numerous performance indicators. However, depending upon the indicator, we oftentimes reach different conclusions regarding transit system performance. The research reported in this paper uses factor analytic methods to generate a set of underlying attributes (factors) that capture the performance of public transit systems in Indiana. Similar to what is reported in the literature, this study finds three attributes that best describe transit system performance: efficiency, effectiveness, and overall performance. Based upon systemsÕ factor scores, the study finds that systems scoring highly on one attribute generally perform well on the remaining attributes. Further, there is an inverse relationship between system performance and subsidies, a finding that supports performance based subsidy allocations.