Effect of land use on decisions of shopping tour generation: A case study of three traditional neighborhoods in WA

This study investigates the relationship between land use and shopping tour generation using an activity-based shopping model that captures the effects of land use patterns on household decisions of shopping tour frequency, tour scheduling and mode choice. The model was calibrated using travel data collected in three traditional neighborhoods located in the Puget Sound region, WA, and shopping travel patterns across seven common household structures were analyzed. The results reveal that land use patterns have virtually no impact on overall shopping tour frequency. However, land use does seem to be associated with decisions about the type of shopping tours undertaken. For example, households with poorer accessibility tend to make fewer one-stop shopping tours, and are more likely to combine shoppingtrips with other trips to form multi-stop shopping tours as a means of compensating for locational deficiencies. Finally, we also found that traditional neighborhood residents who live closer to the neighborhood commercial street, and thus, have greater accessibility, are more inclined to use non-auto modes for one-stop shopping tours.     

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.     

不确定系统的保性能可靠控制

针对不确定线性连续系统,研究了执行器失效情况下的保性能可靠控制问题.利用LMI给出了不确定线性系统对执行器故障具有渐近稳定性及可靠保性能的充分条件,进而讨论了参数不确定线性系统的保性能可靠控制器的设计问题.根据凸优化理论,给出了最优保性能可靠控制器的线性凸优化设计算法和设计步骤.采用所设计的可靠状态反馈控制器,当任意执行器出现故障时,闭环系统仍保持渐近稳定且保持原有的性能指标.     

A Remote Real—Time Monitoring System for Power Quality

Introduction　　Withthewideapplicationofelectricpowerequipmentandelectronicdevicestoelectricrailways ,thenonlinearimpactloadinpublicsupplynetworksincreasesunceasingly .Itleadstopowervoltage qualitydeterioration ,powerharmonic pollutionandsevereinterferenc…     

交通需求管理及其在中国的应用

交通需求管理 ( TDM)是发达国家已经广泛研究、试验和实施的一项旨在解决目前交通问题的有效措施。综合分析了 TDM在几个典型发达国家的应用情况及其经验 ,初步分析了该措施在中国应用的可行性 ,认为目前不能全面引入 TDM措施 ,但需要在大力发展的交通规划与管理中引入 TDM思想 ,并以此作为长远的发展目标     

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．     

大学英语口语测试及评估的几点基本考虑

通过以大学英语考试的口语测试和2003年研究生入学考试中的英语口语测试的效果为例，从其效度和信度方面，分析面对面的口语测试和非面对面的口语测试的优缺点，得出进行能客观反映学生口语水平的高质量的口语测试是可能的。     

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。     

基于蚁群优化算法与出租车GPS数据的公众出行路径优化

以出租车GPS采集的浮动车数据为依据,研究出租车驾驶员路径选择的认知及类蚂蚁的行为特征。根据城市道路功能等级与出租车的通行频率等信息素,建立出租车驾驶员路径选择信息素等级路网,并以此作为路网初始信息素,综合考虑路径通行时间、通行距离、路径信息素等级等多个因素,提出了基于蚁群优化算法的公众出行路径规划优化算法。以武汉市路网和浮动车为试验数据,将模型规划的道路与浮动车数据库中的轨迹进行了比较。结果表明:基于蚁群优化算法与出租车GPS数据的公众出行路径同出租车驾驶员选择的出行路径相似度很高,能为公众出行提供出租车驾驶员选择的行车路径。