Torsion beam axle system design with a multidisciplinary approach

This research proposes an automatic torsion beam axle optimization process with a multidisciplinary approach and generates the optimal torsion design parameters, such as thickness and shape. In order to construct an automatic analysis process, multidisciplinary analysis models, such as modal analysis, roll mode dynamic analysis, and fatigue analysis, were applied in batch mode. To understand the design space, a parametric study using the torsion beam thickness and shape was performed. Considering roll durability and K&C characteristics, the torsion beam axle could be optimized. For the automated design process, a PIDO tool called PIAnO was used. In conclusion, a reduction in the computer-aided simulation time was achieved, and the durability and K&C characteristics of the torsion beam were enhanced by optimizing the thickness and shape.     

随动转向的分析与综合方法研究

基于侧偏柔度的随动转向研究,从四轮转向力反馈控制的角度对随动转向的稳定性和鲁棒性进行了研究,提出一种随动转向非线性弹性特性的综合方法。     

Why do people fare evade? A global shift in fare evasion research

ABSTRACT

Fare evasion is a significant concern for most transit authorities. The traditional approach to fare compliance has focussed on modifying the physical control of ticketing or ticket inspection rates. Yet recently the perspective on fare evasion has begun to shift toward profiling the fare evader or understanding the customer motivations to fare evade. This paper uses a literature review method to document the characteristics of these three perspectives on fare evasion: the conventional transit system perspective, the customer profiling perspective and the customer motivations perspective. We find that the conventional transit system perspective, although straightforward to measure and control, has its limits particularly in “open” transit systems. The customer profiling perspective attempts to identify, based on demographics, which customers are more likely to fare evade. However this perspective has little use beyond profiling and is ethically questionable. The customer motivations perspective provides a richer understanding of how customers define fare evasion and what attitudes, social norms and circumstances motivates them to fare evade. Considering that between 20% and 40% of a city’s residents admit to fare evading at some point, understanding these complex motivations can help improve revenue compliance at a time when most governments heavily subsidise their transit systems.     

西部地区道路交通事故灰色模型GM（1，1）研究

为掌握西部事故高发地区的交通事故特征,在2008—2012年国道314、219,叶城县、塔县地区道路交通事故统计资料基础上,运用灰色原理建立一阶单变量GM（1,1）预测模型,对上述地区道路交通事故的事故数、死亡人数进行短期预测。经精度检验,灰色预测结果精度高,且与实际相符。与传统预测方法相比较其更科学、更合理。     

关于新时代我国综合交通运输发展的若干思考

为进一步明确交通强国背景下我国综合交通运输发展战略，从理论和实践两个层面论证交通强国与综合交通运输的辩证关系，在此基础上分析了供给侧结构性改革、国家战略支撑、区域协调发展、科技创新、扩大对外开放、治理体系和治理能力现代化等对综合交通运输发展的新要求。以习近平关于综合交通运输的重要论述为根本遵循，研究提出新时代我国综合交通运输发展安全、便捷、高效、绿色、经济的价值导向、总体思路，探讨基础设施、运输服务、科技创新、治理体系四个方面的战略重点，为交通强国背景下我国综合交通运输发展构建了总体战略框架。     

Marine Shoreline Management—A 35-Year Evaluation of Outcomes in San Juan County,Washington, US

In 1976, Washington became the first state to implement the federal Coastal Zone Management Act (CZMA) primarily through the 1971 WA Shoreline Management Act (SMA). However, there has been little effort in Washington to evaluate outcomes of shoreline protection programs post SMA. In 2006–2008, we characterized shoreline conditions in San Juan County over three time periods spanning pre and post SMA and engaged community members to improve effectiveness of shoreline protection. We found modest improvements in forest retention on marine shorelines between pre and post 1977, but few other improvements through time. While we could not measure shoreline construction rates, construction practices for shore armor and overwater structures (docks) have changed very little, despite the increased regulatory standards. The vast majority of shore armor constructed post SMA occurred without mandatory county or state permits likely due to: widespread perception that permits were unnecessary and that permit standards were arbitrary and inconsistently applied; poor understanding of shoreline ecology by community members; lack of county or state enforcement authority and shoreline monitoring programs; and poor permit tracking systems.     

多用途船能效符合证书申领的实践研究

通过对国内某船厂21000dwt多用途船申请船舶能效符合证书的实践过程研究，阐述了文件送审、现场试验验证以及终审过程中的注意事项和要点，明确了各个阶段船厂或船级社的各自责任，为相关方申请船舶国际能效证书／船舶能效符合证书提供参考和借鉴。     

An optimal variable speed limits system to ameliorate traffic safety risk

Active Traffic Management (ATM) systems have been emerging in recent years in the US and Europe. They provide control strategies to improve traffic flow and reduce congestion on freeways. This study investigates the feasibility of utilizing a Variable Speed Limits (VSL) system, one key part of ATM, to improve traffic safety on freeways. A proactive traffic safety improvement VSL control algorithm is proposed. First, an extension of the METANET (METANET: A macroscopic simulation program for motorway networks) traffic flow model is employed to analyze VSL’s impact on traffic flow. Then, a real-time crash risk evaluation model is estimated for the purpose of quantifying crash risk. Finally, optimal VSL control strategies are achieved by employing an optimization technique to minimize the total crash risk along the VSL implementation corridor. Constraints are setup to limit the increase of average travel time and the differences of the posted speed limits temporarily and spatially. This novel VSL control algorithm can proactively reduce crash risk and therefore improve traffic safety. The proposed VSL control algorithm is implemented and tested for a mountainous freeway bottleneck area through the micro-simulation software VISSIM. Safety impacts of the VSL system are quantified as crash risk improvements and speed homogeneity improvements. Moreover, three different driver compliance levels are modeled in VISSIM to monitor the sensitivity of VSL effects on driver compliance. Conclusions demonstrated that the proposed VSL system could improve traffic safety by decreasing crash risk and enhancing speed homogeneity under both the high and moderate compliance levels; while the VSL system fails to significantly enhance traffic safety under the low compliance scenario. Finally, future implementation suggestions of the VSL control strategies and related research topics are also discussed.     

船舶安检中对安全管理规则符合性检查的探索与实践

海事机关对船舶进行安全管理规则符合性检查是监督船舶执行安全管理规则，确保船舶安全和防止污染的重要手段。如何更加有效地进行船舶安检是摆在海事检查官面前的重要课题。文中从实践出发探索安检中对安全管理规则符合性检查的方法和缺陷处理的途径。     

制动—驱动工况下的轮胎侧偏特性理论研究

本文通过考虑制动和驱动工况下的轮胎印迹内垂直载荷分布的不同，建立了比以往模型更完善的制动－驱动工况下的轮胎侧偏特性理论模型，以６．５０Ｒ１６轮胎为例，分析了滑移率，侧偏角和垂直载荷分布形状参数等对其侧特性的影响。