轿车人体坐姿校核分析研究

通过研究人体尺寸与汽车内部空间的关系及近似车型的舒适人体坐姿,并根据设计车型的空间综合考虑,得出设计人体坐姿,并可根据参考车型评价其舒适程度。     

Experiences with Competitive Tendering of Bus Services in Germany

Abstract

After a long transition period with only a few isolated procedures for competitive tendering, the market for German public transport bus services has seen numerous such tenders in recent years. The results are complex. From the public transport authorities’ point of view, the main effects are a decrease in subsidy payments, with relatively low expenses relating to the tendering process (allocation, contract management). The overall level of competition is high, with five to seven bidders on average, although this has been declining in recent years. Entry barriers have been identified at significant levels for several parameters, especially with respect to the volume tendered and the revenue risk to be borne by the operator out of net‐cost contracts. Demonstrably small‐ and medium‐sized transport operators have been able to increase their market share in the starting phase of introducing tendering, with diminishing success rates in recent years. Due to the increased quality requirements in competitive tendering, the quality of public transport available has improved considerably, and environmental standards have been better implemented and sustained. As far as employees are concerned, a trend towards wages below the wage rate of private operators cannot be observed. However, their level is well below the level of public incumbent operators.     

Examining pedestrian-injury severity using alternative disaggregate models

This paper investigates the injury severity of pedestrians considering detailed road user characteristics and alternative model specification using a high-quality Danish road accident data. Such detailed and alternative modeling approach helps to assess the sensitivity of empirical inferences to the choice of these models.     

From theory to practice in road safety policy: Understanding risk versus mobility

This paper reviews theoretical issues surrounding transport safety modeling and the implications for road safety policy. The behavioral mechanisms that affect transport safety are typically not considered in safety modeling. These issues are discussed in the context of trade-offs between risk-taking, as perceived by travelers, and other mobility objectives and the attributes associated with them. This is an extension of other theoretical frameworks, such as risk compensation, and attempts to integrate some of the previous frameworks developed over the years. Various examples of behavioral adaptation to specific policies are discussed and linked to the framework. These issues are then discussed in the context of improvements to empirical work in this area and the linkage of theoretical frameworks to crash modeling, in particular the estimation and use of Crash Modification Factors. Conclusions suggest that there are many deficiencies in practice, from estimation of models to choice of effective policies. Progress is being made on the former, while the publication of practical guidance seems to have substantial lags in knowledge.     

Estimating demand variables of maritime container transport: An aggregate procedure for the Mediterranean area

Demand variables of maritime container transport (throughput, transhipment and origin–destination flows) may be estimated with freight demand models. As their parameters generally vary both in time and space, models may not be transferable to geographical areas and time periods differing from that for which they are calibrated.     

Strategies of state and local government in management of urban transport problems – A case of Delhi

In India, different layers of Government control different policy instruments to tackle transport externalities which might result in coordination problems and possible efficiency losses. This paper, therefore, addresses the coordination problem resulting from the division of policy instruments between two different government levels that face different types of externalities in varying degrees of magnitude in the urban transport sector by developing three types of theoretical models: the Full Control Centralised Model where the state government has full control over all pricing instrument; a Nash equilibrium model where each of the government levels controls only one instrument and takes the behaviour of the other as given; and a Stackelberg equilibrium mode where the behaviour of the state government is influenced by the fact that one of the price instruments is controlled by the local government. With an empirical illustration of the model for Delhi, the paper finds that since there are many interactions and many externalities between the two levels of government, a division of roles between them does not guarantee an efficient pricing outcome and the efficiency of pricing would depend on the institutional set up and on the correspondence between the objective functions of the two government levels.     

公交车安全气压窗及火灾隐患监测预警器设计

针对紧急情况下公交乘客的逃生需求,设计了一种气压式安全公交车窗,当事故发生时,使车窗在3s内打开,为乘客提供及时有效的逃生通道。通过制作模型和力学分析计算,此设计既能在常规状态下保证车窗的强度和密封性,又能在紧急情况下使其迅速开启。此外,为预防事故,以AT89S52单片机为核心,采用2M007型可燃气体传感器和MQ-2型烟雾传感器建立公交车火灾监测报警系统,实时检测发动机舱及车体内可燃气体浓度和烟雾情况,具有声光报警功能。结合GSM通信模块,向公交车指挥中心传输报警信息,以便进行救援指挥。     

基于GSM的汽车空调远程控制系统设计

通过对汽车空调控制系统特点的分析,提出以STC89C51单片机为控制核心,通过GSM网络对汽车空调系统进行短消息远程控制的思路.并依据此思路完成系统相应硬件和软件设计.该系统操作简单、成本低廉,而且不受距离和障碍物的影响,对于提高汽车的舒适性有很大的实用价值.     

基于GSM网络的车载远程报警系统的设计

采用GSM技术设计了车载远程报警系统。该系统以微处理器为控制核心,利用传感器的报警信号,使GSM模块在发生警情的同时发送短信到指定的号码,并且通过CAN总线控制车身其它单元,有效地提高了汽车防盗性能。     

WC5R煤矿用防爆柴油机无轨胶轮指挥车设计

为积极响应国家政策,保障煤矿高产高效、安全生产,设计开发了WC5R煤矿用防爆柴油机无轨胶轮指挥车,介绍了其设计原理及总体结构。