工程设计与施工一体化模式及工作程序

介绍了设计施工一体化模式及其工作程序，论述了设计施工一体化模式的主要特点，并结合国外公路设计施工一体化具体项目实施，总结了设计施工一体化项目的工作程序和应注意的问题。     

滨海新区西中环跨海河大桥方案设计

现代城市的发展对桥梁在美学上提出了更高的要求,该文简要介绍了西中环跨海河大桥方案的总体构思、桥型布置、主体结构、美学理念等。     

弹性需求下多类型用户拥挤收费模型

基于时间价值不同的多类型用户特性,提出了弹性需求下多类型用户的拥挤收费模型,并以一个简化的路网实例比较了多类型用户收费模型与单一类型用户收费模型的区别。简化实例分析结果表明:当费率水平较低时,单一类型用户收费模型高估了路网的流量、社会效益,当费率水平较高时,则低估了路网的流量和社会效益;同时单一类型用户收费模型的路网社会效益和利润区域对应的道路通行能力区间较宽,费率水平区间窄,而多类型用户收费模型的路网社会效益和利润区域对应的道路通行能力区间相对较窄,费率水平区间较宽。     

广西南宁市竹溪立交总体设计思路

文章针对广西南宁市竹溪大道民族大道立交工程的特点,提出了总体设计思路。运用互通立交与周边建筑、环境关系的理论,分析了互通立交设计方案的优劣,并对城市互通立交设计方案与综合交通环境和人文景观环境的关系提出见解和意见。     

Reduction of capacity and projected costs associated with seat belt installation on school buses

This study examines the potential effects the installation of seat belts on school buses would have on the fleet capacity in Alabama and the resulting cost implications. The study also documents the myriad research studies and professional opinions offered on the potential safety effects of equipping school buses with safety restraints/seat belts. Four seat configurations for the school buses were analyzed. The first configuration represents the most common current bus seating configuration without seat belts, 3 seats on each side of the aisle and 12 rows (3/3-12). The physical space required for seat belt hardware may result in a loss of a row of seats and may reduce the number of students seated per row. Thus, three more configurations were studied: loss of a row of seats (3/3-11), loss of one seat per row (3/2-12), and loss of both a row of seats and a seat per row (3/2-11). The capacity for each configuration for each bus using current pupil loads was determined. The costs associated with installation of seat belts, and purchase and operation of new buses were obtained. Should school bus seat belts become mandatory in Alabama, the results obtained in this study can be used by any school system to determine the optimum configuration for their pupils, which will identify the number of additional buses that must be purchased by the school system. This study found that many of the buses that would become overloaded due to seat belt installation and the resultant loss of seating will be carrying only a few excess pupils. Transportation supervisors may be able to handle such overloads by transferring these pupils to other buses or by adjusting their bus routes to minimize purchase of new buses. Additional suggestions for handling bus overloads were offered in the body of this report.     

谈谈机制砂在工程中的应用

该文以永蓝高速公路工程应用机制砂于混凝土为实例,对机制砂混凝土与河砂混凝土的性能进行了比较,阐述了机制砂混凝土配合比设计中的几个关键步骤及应注意的问题,并阐述了机制砂代替天然砂应用到混凝土中的体会,指出了采用机制砂混凝土不仅可提升资源利用率,节约建造成本,又可保证工程质量。     

ATIS条件下出行时间节约效益评价方法研究

在简要论述先进的出行者信息系统(advanced traveler information system,ATIS)项目评价重要性的基础上,结合中国ATIS项目的特点,从中宏观的角度出发,在虑及多种因素的条件下,如地方的经济因素、驾驶员的行为因素等,阐述了ATIS条件下出行者节约时间效益的评价方法.最后,对上海市外环线浦西段交通监控诱导系统进行了评价,验证了这一研究成果的科学性和实用性.     

汽车座椅高度调节器核心构件优化设计

汽车座椅安全性设计的主要目标就是尽可能避免座椅结构损坏和功能失效情况的发生.高调器作为汽车座椅的部件之一,其功能的好坏直接影响安全性.文章主要根据某款轿车驾驶员座椅在高度调节过程中失效的原因进行分析,设计一种解决高调失效的有效结构设计方案,该方案重新设计了高调器核心件内部销柱的结构.对重新设计的高调器进行疲劳耐久试验,试验结果表明,改进后的高调器可有效解决高调失效的问题,提高了汽车座椅的安全性.     

濮鹤高速公路路基工程中三维网垫植草护坡的应用与效益分析

在总结濮鹤高速公路路基三维网垫植草护坡工程实践的基础上,着重阐述了三维网垫植草护坡的作 用机理、施工工艺、草种选择和养护等关键技术,并从工程效果、经济效益和社会效益3个方面对三维网垫植草护 坡进行了效益分析,为河南省高速公路建设进行全线绿化和建立生态道路提供了借鉴和参考。     

Intra-household bargaining for school trip accompaniment of children: A group decision approach

This paper tests a group decision-making model to examine the school travel behavior of students 6–18 years old in the Minneapolis-St. Paul Metropolitan area. The school trip information of 1737 two-parent families with a student is extracted from Travel Behavior Inventory data collected by the Metropolitan Council between the Fall 2010 and Spring 2012. The model has four distinct characteristics including: (1) considering the student explicitly in the model, (2) allowing for bargaining or negotiation within households, (3) quantifying the intra-household interaction among family members, and (4) determining the decision weight function for household members. This framework also covers a household with three members, namely, a father, a mother, and a student, and unlike other studies it is not limited to dual-worker families. To test the hypotheses we build two models, each with and without the group-decision approach. The models are separately built for different age groups, namely students 6–12 and 12–18 years old. This study considers a wide range of variables such as work status of parents, age and gender of students, mode of travel, and distance to school. The findings of this study demonstrate that the elasticities of the two modeling approaches differ not only in the value, but in the sign in some cases. In 63% of the cases the unitary household model underestimates the results. More precisely, the elasticities of the unitary household model are as much as 2 times more than that of the group-decision model in 20% of cases. This is a direct consequence of model misspecification that misleads both long- and short-term policies where the intra-household bargaining and interaction is overlooked in travel behavior models.