云南庄特大桥三角区施工方案

云南庄特大桥主桥为(150+280+150) m预应力空腹式连续刚构桥。主梁根部三角区分为空腹区和汇合区,总长约134 m,三角区结构受力复杂,施工难度大,工期紧,通过方案比选确定三角区采用斜拉扣挂辅助悬臂浇筑施工方案。上、下弦节段通过张拉临时扣索作为节段的支撑结构,利用挂篮分别悬浇上、下弦节段。上、下弦合龙前先拆除下弦挂篮部分结构,仅用上弦挂篮施工汇合区节段混凝土。该方案能有效避免上、下弦施工互相干扰,有利于工期控制及质量保证。利用MIDAS Civil软件对三角区施工方案进行受力分析,计算结果满足要求。     

重庆轨道交通三号线嘉陵江特大桥菱形挂篮设计与施工

结合重庆轨道交通3号线嘉陵江特大桥主桥挂篮施工的实际情况,介绍所用挂篮的构造、特点、结构计算,以及挂篮在曲线段准确就位等方面的主要施工技术。     

人口老龄化背景下香港地铁服务满意度分析与改进策略研究

我国的人口老龄化趋势日益凸显,受到政府和社会的高度关注。实施积极应对人口老龄化国家战略,满足老年人多层次、多样化需求成为国家的中心工作之一。地铁是老年人重要的出行方式和移动性保障,本研究基于270名老年人对香港地铁(MTR)服务满意度的问卷调查数据,建立随机森林模型关联整体满意度与属性满意度,并构建“重要性-满意度”指数识别地铁属性适老化改进的优先级。研究发现：老年人对地铁服务基本满意;老年人重点关注的地铁服务属性是候车空间、优先座位和行车稳定性;老年人较少关注的属性是发车频率和准时性;改进优先级最高的地铁服务属性是优先座位、车厢温度和站点可达性。据此,针对性提出地铁适老化改进策略。     

基于乘客满意度的公交车站立乘客面积研究

公交车内站立乘客面积是影响公共交通乘车阶段乘客满意度的关键指标.将使乘客感受由不满意转变为满意的公交车站立乘客面积的临界值定义为临界站立乘客面积.本文旨在提出临界站立乘客面积的建议值.首先,在呼和浩特市开展了客流调查及问卷调查;然后,基于调查所获数据,采用有序 Logistic回归建立了乘客满意度与站立乘客面积的模型;最后,通过对所建模型的图形化分析,提出临界站立乘客面积(即保证乘客满意的最小站立乘客面积)的建议值为 0.25 m2/人.本文研究成果为公共交通乘车阶段的乘客满意度评价、舒适性评价提供量化依据,为公交车额定载客量的核定提供新思路.     

出行者出行方式选择行为的重复博弈分析

利用博弈理论,建立了出行者出行方式选择行为的博弈模型,并将一次博弈模型扩展至重复博弈模型.通过分析得到出行者合作策略稳定运行的条件,即当博弈方都比较注重长远利益的情况下会选择合作策略.由于出行者在进行博弈时,可能会“犯错误”,因此建立了具有颤抖效应的重复博弈模型,给出了博弈方在可能犯错情况下的收益,这种情况更符合实际,通过分析得到了在博弈方都比较注重长远利益的情况下均会采取触发策略.本文从理论上建立了有效地激励出行者选择公交车出行的决策机制、激励惩罚机制,并针对目前的公共交通现状给出了相应的对策与建议,以期为公共交通建设创新提供依据.     

基于模糊群组AHP的舰船装备保障部门绩效评估

引入模糊集理论,将传统AHP扩展为模糊群组AHP,并应用于舰船装备保障部门绩效评估。采用模糊Delph i法集成多个专家的意见,确定一级指标的三角形模糊数权重;用模糊语言变量来描述二级指标的模糊权重和满意度,结合层次集成的模糊算法得到绩效的三角模糊数评价;借助Lee-L i的模糊数排序方法,确定绩效评价值,从而得出其属性判定。算例表明该方法合理有效。     

共享汽车持续使用意愿影响因素研究——基于感知理论

随着共享经济的发展,大众对出行的要求越来越高,共享汽车已逐渐成为日常出行的选择之一。本文基于感知价值,结合感知质量和感知娱乐性,探究其与用户满意度的关系,并引入感知风险,提出对用户持续使用意愿影响因素的新理论模型,通过调查问卷探究因素并分析数据。结果表明感知价值和感知质量是影响用户持续使用意愿的重要因素。     

Dockless bike-sharing systems: what are the implications?

ABSTRACT

The emergence of dockless bike-sharing services has revolutionised bike-sharing markets in recent years, and the dramatic growth of shared bike fleets in China, as well as their rapid expansion throughout the world, exceeds prior expectations. An understanding of the impacts of these new dockless bike-sharing systems is of vital importance for system operations, transportation and urban planning research. This paper provides a first overview of the emerging literature on implications of dockless bike-sharing systems for users' travel behaviour, user experience, and relevant social impacts of dockless bike-sharing systems. Our review suggests that the dockless design of bike-sharing systems significantly improves users' experiences at the end of their bike trips. Individuals can instantly switch to a dockless shared bike without the responsibility of returning it back to a designated dock. Additionally, the high flexibility and efficiency of dockless bike-sharing often makes the bike-sharing systems' integration with public transit even tighter than that of traditional public bikes, providing an efficient option for first/last-mile trips. The GPS tracking device embedded in each dockless shared bike enables the unprecedented collection of large-scale riding trajectory data, which allow scholars to analyse people's travel behaviour in new ways. Although many studies have investigated travel satisfaction amongst cyclists, there is a lack of knowledge of the satisfaction with bikeshare trips, including both station-based and dockless bikeshare systems. The availability and usage rates of dockless bike-sharing systems implies that they may seriously impact on individuals' subjective well-being by influencing their satisfaction with their travel experiences, health and social participation, which requires further exploration. The impact of dockless bike-sharing on users' access to services and social activities and the related decreases in social exclusion are also relevant issues about which knowledge is lacking. With the increases in popularity of dockless shared bikes in some cities, issues related to the equity and access and the implications for social exclusion and inequality are also raised.     

电动汽车Cruise模型及其动力经济性匹配分析

根据某电动汽车的计算参数,文章在理论研究的基础上,对驱动电机、动力电池、传动系统和轮胎进行了参数匹配。基于AVL Cruise建立了整车性能仿真模型,继而对该款电动汽车整车进行了动力性和经济性模拟仿真分析。通过仿真验证了该款汽车动力性指标和经济性指标均符合要求,且验证了其动力系统理论匹配和经济性分析方法的合理性。