公交候车时间容忍阈值的分布特征及影响因素

公交候车时间容忍阈值反映的是出行者能够容忍的最长候车时间. 研究公交候车时间容忍阈值有助于我们更好地理解出行者对候车时间的感知和态度，从而采取针对性的对策提高公交吸引力和分担率，并可以为公交运营组织提供参考. 本文采用昆明市的调查数据，对候车时间容忍阈值进行了实证研究. 首先，对候车时间容忍阈值的分布特征进行了统计分析，并采用秩和检验法对不同群体的候车时间容忍阈值的分布差异进行了检验. 进一步，基于序次Logit 模型识别了候车时间容忍阈值的影响因素，发现年龄、受教育程度、年龄和受教育程度的交互项、职业、家庭年收入、公交出行频率对候车时间容忍阈值有显著影响.     

Exploring the distances people walk to access public transport

ABSTRACT

A shift from private motorised transport to more active transportation can, among other things, deliver significant health benefits. The main disadvantage of active transport (in particular walking) for most people compared to private motorised transport is the limited range. Public transport (PT) can complement the use of active modes and extend their range. Therefore, there might be potential to increase physical activity through an increase in PT use. This article takes a closer look at how walking relates to the use of PT by examining existing literature on the topic. It aims to study how far people walk to and from PT and what key factors influence this. Scopus, Transport Research International Documentation and Web of Science have been searched systematically for relevant articles, conference papers and books. After screening of titles and abstracts, 41 relevant publications were identified. Studies were included if they quantified the amount of walking (measured as either distance or time) that is directly related to the use of PT. Studies that quantified walking using general measures of daily physical activity or daily walking or that used stated preference designs were excluded. The PT systems considered in this paper are mass transport systems in urban areas, either road- or rail-based, with fixed schedules and stops. Demand responsive transport services, which can offer door-to-door travel, are not considered, as these systems can to a large extent eliminate the need to walk. In the identified publications, a large variety of walking distances and times have been reported, and these seem to be highly context-specific. The paper establishes the evidence for the wide range of factors that influence walking related to PT, which have been categorised as personal, PT-related, environmental, and journey-related. The different methods that have been used are discussed by critically analysing their advantages and limitations. Only a limited number of these methods used allow for an accurate assessment of the walking distances to and from PT. The paper concludes with suggestions for future research, such as a need for more accurate measurement of walking and research in different geographical areas to shed light on underlying influences of culture and climate.     

A comparative analysis of transportation-based accessibility to mental health services

The demand for mental health services has been growing stronger over the last couple of decades. This indicates the need to study and assess the access to these mental health services especially with a focus on the vulnerable populations having the greatest need. As such, this paper presents a Geographical Information Systems (GIS)-based analysis in order to study and evaluate the accessibility of mental health facilities using the information on the spatial distributions of population and facilities, and regional traffic characteristics. For this purpose, different age group segments are utilized including the total population as well as those aged between 18 and 21, 22 and 49, 50 and 64, and those aged over 65 and 85. Focusing on the State of Florida, spatially detailed accessibility metrics are calculated with regard to healthcare facilities using travel times between population block groups and these critical mental health facilities. These estimates are used to calculate the weighted county accessibility scores for each county. Findings clearly delineate those counties that lack access to mental facilities, especially those in Northwest Florida, a demographically diverse and substantially rural region. This type of analysis can help planners and policy makers develop better strategies in order to provide adequate mental health care options needed in targeted locations.     

适应市场经济发展推行公路养护工程招标制

由于传统的公路养护体系、养护方式有许多弊端 ,因此推行公路养护工程招投标制势在必行     

城市多模式公交网络拓扑结构与布局均衡性研究

为探究城市多模式公交网络的均衡性，实现其量化测度，界定了公交网络均衡性内涵，从网络拓扑结构及其道路布局两方面入手开展研究。分析并总结了传统网络拓扑建模方法存在的不足，考虑公交线路双向路径与运能差异，提出增广Space L网络模型，建立了其矩阵表示与拓扑结构表征指标；着眼于公交网络与城市道路的依赖与伴生关系，建立了P-R二分网络模型，从线路和运能两方面构造了其矩阵表示及表征指标，并阐释了各指标的现实意义。为避免单一指标评价产生片面性结果的风险，提出了Gini系数与Atkinson指数相结合的均衡性测度思路，考虑指数分布的普遍性，构造了面向公交网络均衡性分析的Lorenz曲线拟合通式，优化了Gini系数求解方法；引入Atkinson指数，以适中的敏感性与区分度为期望，给出平等偏好参数建议值ε=1.5，结合表征指标的离散性，建立了Atkinson指数优化计算方法。以南京市主城区多模式公交网络为案例，建立了空间地理信息数据库并开展建模分析，基于表征指标分布，证实了公交网络有向处理的必要性，指出南京公交网络发展存在典型的"马太效应"；构造了各表征指标的Lorenz曲线，验证了拟合通式的合理性与有效性；求得各表征指标Gini系数与Atkinson指数值。测度结果表明：南京公交网络布局及其对道路空间的利用相对均衡且合理，但运能分布略欠均衡，公交网络效率与可达性的实现对极少数路段的依赖性较高，集中于区域间联络性道路；ε=1.5时，Atkinson指数与Gini系数的评级结果无明显分歧，但具体测度值显示出一定区分度，前者具有更高的敏感度，证实了二者在公交网络均衡性测度中的有效性与互补性。     

有反馈和N-策略多重休假的M^X／（G，Gm）／1排队模型

研究N-策略多重休假下，顾客是批量到达的M^x（G，Gm）／1排队模型。一旦系统空闲服务台就开始一个随机长度的休假，休假结束后，如果发现顾客数达到或超过N，就立即对顾客进行服务直到系统空闲，如果发现顾客数小于N，就进行下一阶段随机长度休假。服务台提供两阶段服务：第一阶段初步服务和第二阶段m种选择服务。在第一阶段初步服务结束后，顾客可以回到队列要求重新服务，也可以立即离开系统，或接受第二阶段m种选择服务中某一种服务。通过补充变量法得到了稳态下系统队长的概率母函数和其随机分解性质。进一步计算出系统稳态的队长及其他性能指标。     

村务公开与村民参与需一体化协调发展

在不断推进社会主义新农村建设的时代背景之下,村民民主管理本村事务早己不再陌生,而出现在点军区桥边镇黄家棚村的村务公开与村民参与度的不对称现象却十分引人注目。村务公开与村民参与的背离是我国农村基层工作中出现的一个不可忽视的问题,本文将本着理论联系实际的方式讨论两者之间的关系,以点军区黄家棚村为蓝本,作出具体论述,以探寻解决之道。     

博弈论在公交枢纽规划布局方案评价中的应用研究

在对传统规划布局方案评价方法存在的不足进行分析的基础上，提出运用博弈论对公交枢纽规划布局方案进行评价。并给出了博弈模型和算法，以期达到最优布局。     

安全电子邮件系统的设计与分析

分析当前电子邮件在安全方面的隐患，设计一种既能实现端到端的电子邮件安全通信又能在传输层建立安全隧道的电子邮件系统，详细介绍了安全电子邮件系统基于PKI体系实现加密、数字签名、身份认证等部分的设计思路。最后对此系统的安全性加以分析，并与PGP及反垃圾邮件系统进行比较。     

船舶主机信息化监控系统

主机监控系统信息化是利用信息技术提高船舶的生命力、机动性、可操纵性,降低机组人员的疲劳强度和保证船舶的安全运行。本文阐述了国内外主机监控系统的现状、发展趋势;提出了基于公共体系结构下信息化主机监控系统发展模式。