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81.
研究了我国路网环境下交通特点、危险品运输特点及危险品紧急事件的风险特征,剖析了危险品运输的致灾因子,提出了路网环境下危险品运输的风险控制一般模式、技术框架和应急保障机制建议,为我国具有特殊性和复杂性的路网环境下危险品运输安全监管提供可借鉴的思路。 相似文献
82.
本文以开发区道路横断面设置为例,着重探讨了双幅路在开发区道路设计中的适用条件,并给出了具体布置方案,为其提供工程实践技术支持。 相似文献
83.
交通高职院校承担着为行业和地方服务的双重任务。随着经济结构调整、产业升级和经济发展方式的转变,交通高职院校要完成支撑产业、服务经济转型的使命,满足经济社会发展的需要,就要适时对专业布局进行优化和结构调整,配备合格的师资,这就需要对教师进行培训。文中围绕教师的培训内容,以报关为例提出了报关师资的培训设计和实现途径。 相似文献
84.
《International journal of injury control and safety promotion》2013,20(4):342-348
Seat belts (SBs) are effective devices for reducing injury risk due to traffic accidents. Seat belt wearing was made compulsory in the United Arab Emirates (UAE) in January 1999 for drivers and front seat passengers (FSPs). No comprehensive study has ever assessed SB wearing rates across the country. Also, little is known on drivers' awareness of the importance of wearing seatbelts and how human factors affect wearing habits. This study aims to determine SB wearing rates for drivers and FSPs in UAE through an observational field study. It also aims to investigate perceptions and behaviour of drivers on this issue as well as human factors that affect wearing rate through a randomly distributed questionnaire. The results of the field study show that the overall SB wearing rate across the country was 61% for drivers and 43.4% for FSPs and that there were significant differences between the seven emirates that constitute the country. The questionnaire results show that age, education level, gender, marital status and nationality of drivers affect wearing habits and perceptions. Future implications in terms of improving traffic safety awareness are discussed. 相似文献
85.
Yoonjin Yoon Mark HansenMichael O. Ball 《Transportation Research Part E: Logistics and Transportation Review》2012,48(1):34-49
Adverse weather is the dominant cause of delays in the National Airspace System (NAS). Since the future weather condition is only predictable with a certain degree of accuracy, managing traffic in the weather-affected airspace is a challenging task. In this paper, we propose a geometric model to generate an optimal combination of ground delay and route choice to hedge against weather risk. The geometric recourse model (GRM) is a strategic Probabilistic Air Traffic Management (PATM) model that generates optimal route choice, incorporating route hedging and en-route recourse to respond to weather change: hedged routes are routes other than the nominal or the detour one, and recourse occurs when the weather restricted airspace becomes flyable and aircraft are re-routed to fly direct to the destination. Among several variations of the GRM, we focus on the hybrid Dual Recourse Model (DRM), which allows ground delay as well as route hedging and recourses, when the weather clearance time follows a uniform distribution. The formulation of the hybrid DRM involves two decision variables - ground delay and route choice - and four parameters: storm location, storm size, maximum storm duration time, and ground-airborne cost ratio. The objective function has two components: expected total ground delay cost and expected total airborne cost. We propose a solution algorithm that guarantees to find the global optimum of the hybrid-DRM. Based on the numerical analysis, we find that ground-holding is effective only when combined with the nominal route. Otherwise, it is optimal to fly on the route determined by the DRM without ground delay. We also find the formula of the threshold ground-airborne cost ratio, which we call the Critical Cost Ratio (CCR), that determines the efficacy of ground delay: the higher the CCR, the more effective the strategies involving ground delay. We conclude that both ground delay and route hedging should be considered together to produce the best ATM decisions. 相似文献
86.
随着公路行业改革的不断深化,公路部门经济活动的范围越来越大,经济业务的内容不断增多,现有会计科目已经不能满足会计核算需要。从2000年开始,我国公路事业单位的财务收支预算已经逐步纳入政府部门预算管理的范畴。随着公路养护会计环境发生的这些变化,就要求相关的会计核算模式进行改革。 相似文献
87.
在新的历史时期,建立学习型公路行业尤为重要.要树立三种学习观,通过建章立制,创新形式等措施,来打造学习型公路行业. 相似文献
88.
加强试验检测工作 提高公路工程质量 总被引:2,自引:0,他引:2
结合当前农村公路工程建设过程中存在的质量问题,浅谈如何加大试验检测工作力度,切实提高农村公路工程质量。 相似文献
89.
90.
《Spatial Economic Analysis》2013,8(4):400-421
ABSTRACTAlthough there is an abundant regional literature analyzing traffic congestion, only a few studies have explored extending such analysis with spatial effects. This study uses a dynamic spatial Durbin model and city-level panel data for the period 2003–14 to investigate the spatial spillover effects of traffic congestion on urbanization in China. The results show that there is an inverted ‘U’-shaped relationship between urbanization and traffic density in local and neighbouring cities, and congestion effects have appeared. In the short and long run, the spatial effects of traffic congestion have become an important force restricting the effective promotion of urbanization in China. 相似文献