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331.
Travel to and from school can have social, economic, and environmental implications for students and their parents. Therefore, understanding school travel mode choice behavior is essential to find policy-oriented approaches to optimizing school travel mode share. Recent research suggests that psychological factors of parents play a significant role in school travel mode choice behavior and the Multiple Indicators and Multiple Causes (MIMIC) model has been used to test the effect of psychological constructs on mode choice behavior. However, little research has used a systematic framework of behavioral theory to organize these psychological factors and investigate their internal relationships. This paper proposes an extended theory of planned behavior (ETPB) to delve into the psychological factors caused by the effects of adults’ cognition and behavioral habits and explores the factors’ relationship paradigm. A theoretical framework of travel mode choice behavior for students in China is constructed. We established the MIMIC model that accommodates latent variables from ETPB. We found that not all the psychological latent variables have significant effects on school travel mode choice behavior, but habit can play an essential role. The results provide theoretical support for demand policies for school travel. 相似文献
332.
333.
This paper investigates the effects of the provision of traffic information on toll road usage based on a stated preference survey conducted in central Texas. Although many researchers have studied congestion pricing and traffic information dissemination extensively, most of them focused on the effects that these instruments individually produce on transportation system performance. Few studies have been conducted to elaborate on the impacts of traffic information dissemination on toll road utilization. In this study, 716 individuals completed a survey to measure representative public opinions and preferences for toll road usage in support of various traffic information dissemination classified by different modes, contents, and timeliness categories. A nested logit model was developed and estimated to identify the significant attributes of traffic information dissemination, traveler commuting patterns, routing behavior, and demographic characteristics, and analyze their impacts on toll road utilization. The results revealed that the travelers using dynamic message sign systems as their primary mode of receiving traffic information are more likely to choose toll roads. The potential toll road users also indicated their desire to obtain traffic information via internet. Information regarding accident locations, road hazard warnings, and congested roads is frequently sought by travelers. Furthermore, high-quality congested road information dissemination can significantly enhance travelers’ preferences of toll road usage. Specifically the study found that travelers anticipated an average travel time saving of about 11.3 min from better information; this is about 30 % of travelers’ average one-way commuting time. The mean value of the time savings was found to be about $11.82 per hour, close to ½ of the average Austin wage rate. The model specifications and result analyses provide in-depth insights in interpreting travelers’ behavioral tendencies of toll road utilization in support of traffic information. The results are also helpful to shape and develop future transportation toll system and transportation policy. 相似文献
334.
This research is aimed at developing a model that maximizes system profit when determining the aircraft routes and flight frequencies in a network. The model employs network flow techniques to effectively collect or deliver passenger flows from all origins to all destinations using non‐stop and multi‐stop flights in multi‐fleet operations. The model was formulated as a multi‐commodity network flow problem. A Lagrangian‐based algorithm was developed to solve the problem. To test the model in practice, a case study is presented. 相似文献
335.
本文详细阐述了一般公路工程路基路面病害及产生病害原因,并针对路面常见病害,根据施工现场所处地质环境,结合已有经验,提出针对性解决方案。对突发性病害、预测难度大等病害,提前做出预防并提出最佳治理方案,降低病害对公路工程的破坏。 相似文献
336.
深圳中信地下商场位于城市繁华地段,地面交通繁忙、地下管线密布,工程地质、水文地质条件复杂,因此采用了以浅埋暗挖和洞内加固为主的施工技术.文章重点介绍了超大管棚预加固技术、开挖方法的研究及优化、二次衬砌的体系转换及监控量测,对其他城市地下空间的开发具有一定的借鉴价值. 相似文献
337.
新建地铁车站零距离下穿既有线区间影响分析 总被引:2,自引:0,他引:2
暗挖隧道下穿既有地铁施工,势必会引起既有地铁结构附加变形和差异沉降,影响其结构及运营安全,需要进行变形和内力分析,以便采取必要保护措施.文章以某暗挖车站密贴下穿既有地铁区间为例,采用FLAC3D和SAP 2000模拟,分析既有地铁区间变形和内力发展规律,评价结构和运营安全受影响的程度,为安全保护提供决策依据. 相似文献
338.
Transportation - Design of effective freight policies requires a comprehensive understanding of freight agents’ interactions. A critical component of the interaction is the freight... 相似文献
339.
铁路客运专线对治理隧道渗漏水提出新的理念,从治理施工中渗漏水着手,以期确保运营后达到一级防水的目标.文章结合大瑶山一号隧道初期支护后渗漏水治理试验段实例,从几方面阐述了灰岩岩溶、砂岩裂隙发育段初期支护后渗漏水成因及特点,提出了本工程岩溶水、裂隙水的治理原则和围岩注浆、局部注浆施工策略. 相似文献
340.