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581.
Can China control the side effects of motor vehicle growth?   总被引:2,自引:0,他引:2  
Motor vehicle growth in China is the fastest in the world. This is placing great strain on the urban environment and causing a rapid increase in oil imports and motor vehicle carbon dioxide emissions. To deal with the environmental and health effects of air pollution, China has adopted a strong motor vehicle pollution control programme and imposed limits on fuel consumption of new light duty vehicles. The article will review these problems and programmes. Special focus will be given to the need to reduce sulphur levels in both gasoline and diesel fuel.  相似文献   
582.
随着经济的快速发展和人民生活水平的提高,机动车保有量快速增长,城市中机动车尾气污染也日益突出,为更有效的控制机动车尾气污染,文章重点分析介绍了我区城市中机动车尾气中氮氧化物排放特征,并提出了控制对策和建议.  相似文献   
583.
货车运行状态(走行稳定性、装载状态、车轮踏面状态、滚动轴承状态)直接关系到行车安全,本文介绍了货车运行状态地面安全监测系统(TPDS)、货车滚动轴承故障早期监测系统(TADS)的国内外现状与发展趋势,讨论了TPDS和TADS检测与诊断技术和应用,结合神华集团铁路实际情况,从先进、成熟、经济、实用、可靠的角度论证了神华集团TPDS和TADS建设的可行性和建设方案,分析了项目实施的社会效益,给出了结论和建议。  相似文献   
584.
我国道路交通安全的现状及其对策   总被引:12,自引:6,他引:6  
由于国民经济的发展 ,使在用车辆逐年大幅度增长 ,同时也使我国的道路交通事故呈逐年增加的趋势。为了改变我国道路交通的严峻状况 ,笔者从我国道路交通的现状出发 ,分析了交通事故率高的原因 ,有针对性地给出了减少交通事故的可行而有效的软硬件措施 ,为道路交通安全改善指出了实现的方法及努力的方向  相似文献   
585.
Problem: To assess how drivers view dangers on the highway, what motivates them to drive safely, how they say they reduce their crash and injury risk, and how they rate their own driving skills. Results: Most drivers rated their skills as better than average. The biggest motivating factor for safe driving was concern for safety of others in their vehicle, followed by negative outcomes such as being in a crash, increased insurance costs, and fines. The greatest threats to their safety were thought to be other drivers' actions that increase crash risk such as alcohol impairment or running red lights. In terms of reducing crashes and injuries, drivers tended to focus on actions they could take such as driving defensively or using seat belts. There was less recognition of the role of vehicles and vehicle features in crash or injury prevention. Impact on research, practice, and policy: Knowing how drivers view themselves and others, their concerns, and their motivations and techniques for staying out of trouble on the roads provides insight into the difficulty of changing driving practices.  相似文献   
586.
PROBLEM: The expected substantial increase in people aged 65 or older is important for those concerned about transportation injuries. However, much of the previous research concentrates on older drivers and overlooks the fact that vehicle and crash factors may provide significant explanations of older occupant injury rates. METHOD: Differences across age groups are explored using two nationwide travel surveys, crash involvement, fatalities, and injuries from crash databases and an ordered probit model of injury severity. RESULTS AND DISCUSSION: Two noticeable differences that help explain injury risk are that older people are more likely to travel in passenger cars than younger people who frequently use light trucks, and that seriously injured older occupants are more likely to be involved in side-impact crashes than their younger counterparts. IMPACT: Increased attention to vehicle engagement in side-impact crashes and to vehicle technologies that can help drivers avoid side collisions would be particularly helpful for older occupants.  相似文献   
587.
Like many other states in the USA, Virginia passed legislation to protect coastal wetlands with limited information on the rate and location of past wetlands conversions. This information, however, can be useful in the design of cost-effective and flexible programs for wetlands management, particularly when such information is used in combination with studies of the socioeconomic value of wetlands. This paper reports on the use of photogrammetric and interpretive methods to determine historical changes in wetlands use for Virginia Beach and Accomack counties, Virginia. Conclusions are drawn as to the use of such information in policy design and program monitoring.  相似文献   
588.
Introduction:The quasi-induced exposure (QIE) method has been widely implemented into traffic safety research. One of the key assumptions of QIE method is that not-at-fault drivers represent the driving population at the time of a crash. Recent studies have validated the QIE representative assumption using not-at-fault drivers from three-or-more vehicle crashes (excluding the first not-at-fault drivers; D3_other) as the reference group in single state crash databases. However, it is unclear if the QIE representativeness assumption is valid on a national scale and is a representative sample of driving population in the United States. The aims of this study were to assess the QIE representativeness assumption on a national scale and to evaluate if D3_other could serve as a representative sample of the U.S. driving population. Method: Using the Fatality Analysis Reporting System (FARS) and the National Occupant Protection Use Survey (NOPUS), distributions of driver gender, age, vehicle type, time, and roadway type among the not-at-fault drivers in clean two-vehicle crashes, the first not-at-fault drivers in three-or-more-vehicle crashes, and the remaining not-at-fault drivers in three-or-more vehicle crashes were compared to the driver population observed in NOPUS. Results: The results showed that with respect to driver gender, vehicle type, time, and roadway type, drivers among D3_other did not show statistical significant difference from NOPUS observations. The age distribution of D3_other driver was not practically different to NOPUS observations. Conclusions: Overall, we conclude that D3_other drivers in FARS represents the driving population at the time of the crash. Practical applications: Our study provides a solid foundation for future studies to utilize D3_other as the reference group to validate the QIE representativeness assumption and has potential to increase the generalizability of future FARS studies.  相似文献   
589.
全自动驾驶已经成为城市轨道交通建设发展的必然趋势,车辆火灾场景是影响列车全自动运行安全最大的场景之一,因此制定合理的火灾调度安全控制方案具有极其重要的意义。以地铁全自动驾驶中车辆火灾场景为研究对象,将系统动力学理论方法用于构建调度安全影响因子模型。与传统的地铁安全模型不同,该模型以全自动驾驶场景为标准形成影响因子库。通过德菲尔法相关思想的专家评分法确定各子系统权重比,利用Vensim-PLE软件对模型进行仿真试验,对各影响因子进行动态预测,对比不同的安全投入方案及调度人员配置比方案,优选出最有效的火灾调度安全控制方案。  相似文献   
590.
针对山区跨越河流输油管道发生原油溢油事故后的不易发现性以及河流溢油事故可能产生的恶劣影响,提出1种通过无人机上装载的高清晰摄像头拍摄识别溢油区域的无人机溢油油头“影迹”寻踪法。该方法对无人机巡线路径进行算法编程,控制无人机的沿河寻油路径,通过无人机识别的溢油区域图片分析溢油油头位置,对溢油量进行大致计算并且能对溢油情况进行初步判断,从而为即将到来的溢油回收环节提供理论数据支撑;能够提高收油效率,大幅度减少山区跨越河流输油管道发生溢油事故后造成污染以及潜在危害的可能性,为油气管道的安全运行提供了一定的保障。  相似文献   
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