智能公交电子站牌显示时间预测方法研究

公共交通智能化调度系统是利用先进的技术手段，动态地获取实时公共交通信息，实现对公交车辆的实时监控和调度，这是公交调度的新模式。公交站点间运行时间预测是城市公共交通智能化调度最重要的工作。研究了基于智能化调度系统的公交电子站牌显示时间的预测理论、模型和方法，旨在为推进我国智能公交系统的快速发展奠定基础。     

基于行程质量的随机用户平衡分配模型

提出行程质量的概念以描述出行者在不确定环境下的路径选择准则。将行程质量定义为行程时间和行程时间可靠性的线性加权和,综合了影响路径选择的两个不同的重要因素:行程时间和行程时间可靠性。假定在路段通行能力随机变化的情况下出行者以估计行程质量费用最小作为路径选择的标准,建立了基于行程质量的随机用户平衡分配模型。证明了模型解的等价性和唯一性,给出了求解模型的MSA算法。在一个小型测试网络上的计算结果表明:模型能够反映出行者在随机路网中的路径选择行为。     

On the goods-activities technical relations in the time allocation theory

In areas like household production and travel choice, time assigned to the different activities plays a key role in addition to consumption as the main variables in utility within the consumer behaviour framework. However, a comprehensive conceptual structure to understand the technological relations between goods consumption and the assignment of time to activities is still lacking. In this paper the problem is reviewed and all possible relations between goods and time are re-formulated. Two general functions are defined and proposed to account for all these relations, forming a new taxonomy for the technical constraints. The resulting consumer behaviour model is used to obtain general expressions for both the value of saving time in constrained activities like travel, and the value of leisure.     

A Remote Real—Time Monitoring System for Power Quality

Introduction　　Withthewideapplicationofelectricpowerequipmentandelectronicdevicestoelectricrailways ,thenonlinearimpactloadinpublicsupplynetworksincreasesunceasingly .Itleadstopowervoltage qualitydeterioration ,powerharmonic pollutionandsevereinterferenc…     

桥梁抗震分析方法

介绍了现行桥梁抗震计算分析的几个方法．确定性方法中的弹性静力法，静力弹塑性分析，反应谱法，时程分析法；概率性抗震分析方法中的随机振动虚拟激励法．并对各个方法的优缺点加以说明，着重介绍了随机振动虚拟激励的基本原理和特点．最后提出了有待进一步研究的几个问题．     

车辆非匀速行驶时路面随机输入的时频研究

首先应用协方差等效方法建立了单轮随机输入非平稳时域模型。根据时间-空间一、二阶微分关系,给出了前后轮变时差相关的问题,较好地解决了非平稳路面时域研究中的低速大幅值波动问题。并由各向同性假设直接得到了车辆左右轮的相关关系,因此适合各种车辆。分析表明Wigner—Ville谱很好地反映了频率特征和路面波形特征。     

Study on Performances of Car-following Models Induced by Motions of a Leading Car

IntroductionReasonably accurate mathematical modeling oftraffic engineering is needed not only for better un-derstanding of the collective behavior of traffic,but also for analyzing flow conditions, designingefficient control strategies, and etc[1]. For the pastfew decades, many researchers made studies of thissubject and a wide range of traffic flow theoriesand models have been developed. According to thelevel-of-detail with which the traffic flow is de-scribed, these traffic models were clas…     

Wind Vibration Study of Long-span Steel Arch Structure of Beijing Capital International Airport

IntroductionThe long-span light-weight steel arch struc-tures have been widely used in the world due to itsbeautiful shape and reasonable mechanical charac-teristics. With the development of the computa-tional theory, the steel arch span becomes longerand longer. So, the wind loads become the majoror even dominant loads applied on steel arch struc-tural system[1~3]. The distress and damage willprobably occur in the structure, because of thelong term wind-induced vibration.1 Structural Wind-in…     

基于桩-土相互作用的内河架空直立式码头地震响应分析

采用有限元法,分别建立桩-土-码头结构模型、地基刚性假定的码头模型和工程计算简化的码头模型。通过模态分析和动力时程分析,得出3种码头模型的基频和水平位移最大值,以及码头立柱内力的最大响应值。研究表明:与地基刚性假定模型相比,由桩-土-码头结构模型所得的结构基频、水平位移最大值、立柱的剪力和弯矩值将会减小,轴力值基本不受影响;与工程计算简化模型相比,结构的基频、立柱的剪力和弯矩值将增大,但是水平位移最大值将减小,轴力值基本不变。