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41.
交通事故发生规律与城市道路系统的规划设计研究   总被引:4,自引:1,他引:4  
笔者分析了城市交通事故发生率与道路等级、道路断面形式、路网密度、交叉口形式、道路车速的关系及交通事故人群的分布规律,认为道路宽而稀、支路缺乏、街道功能不清是我国城市道路网与用地微观布局的基本特点。大量数据分析表明,这种路网体系与我国的城市交通事故率偏高有着密切关系。路网规划是城市路网建设的基本依据,笔者认为,应当将降低城市交通事故率作为路网规划的考虑内容之一,同时指出,应在路网规划中合理选择道路断面形式、交叉口形式,建议适度加密路网、健全支路体系、理清街道功能,并考虑城市道路的车速控制与驾驶心态调整。  相似文献   
42.
为了使驾驶者安全驾驶,达到减少交通事故和降低保险公司理赔支出的目的,笔者的研究课题是从安全角度出发,通过条款细分的方法讨论了安全驾驶与保费厘定之间的关系,确立了“以人为本”、“从车原则”的车险条款厘定细分原则。通过分析人的性别、年龄、驾龄、驾驶记录因素、车的安全性能和使用方式等因素对安全驾驶的影响,可以得出以下结论:适当减少安全驾车者的投保费用,增加风险大的驾驶者和投保车辆的投保费用,这样可以做到以防为主,减少交通事故发生,发挥保险对交通危险的调控作用,也有利于整治保险行业的违规行为,实现车险市场的公开、公平、公正的竞争态势。  相似文献   
43.
Various federal regulations require states to evaluate the effectiveness of their vehicle inspection and maintenance (I/M) programs in reducing in-use emissions. One method to evaluate program effectiveness is to compare initial and final program test results of individual vehicles. Unscheduled emissions measurements, from remote sensing measurement or roadside pullover testing, can also be used to provide an independent assessment of program effectiveness. We compared emissions reductions from the Arizona IM240 program measured by program data and a large set of remote sensing measurements. Remote sensing measurements indicate smaller emission reductions from the program than those calculated directly from program test results. We discuss some possible causes of the differences obtained from the two sets of measurements.  相似文献   
44.
不同类型机动车尾气中芳香烃化合物含量分析   总被引:1,自引:0,他引:1  
首次对北京市9种车辆、5种燃料在不同工况下排放芳香烃化合物的特征.进行了定量研究。结果表明,车型、燃料、净化器及工况等因素对排放量产生影响,电喷车比化油器车芳香烃化合物排放量低;汽油车排放量最高,柴油车其次,LPG及CNG车排放量最低;使用净化器可以降低芳香烃排放量;不同工况对排放量的影响随车型,燃料类型的不同而不同。  相似文献   
45.
美国资产证券化中的政府作用对我国的借鉴   总被引:1,自引:0,他引:1  
美国政府在资产证券化创设过程中发挥了巨大的作用。为推动我国资产证券化的开展,我国政府可借鉴美国做法,采取修订法律、营造金融环境、设置政府机构等措施。  相似文献   
46.
福州市机动车污染及其控制对策   总被引:1,自引:1,他引:1  
陈金平 《福建环境》2001,18(2):35-37
通过对福州市城区道路的车流量及车辆构成状况的调查,估算城市中心区域机动车排气CO、THC和NO2的污染物排放量,分析不同车型的机动车排气污染和贡献率,提出对机动车排气污染的控制对策措施。  相似文献   
47.
根据本单位生产设备特点及车轮的工艺要求,进行工艺分析,设计实用、可靠、灵活、操作简便的通用打字模。  相似文献   
48.
我国在用汽车排气污染物检测方法及应用进展   总被引:1,自引:0,他引:1  
我国两项在用汽车排放标准于2005年发布以来,新规定检测方法的优点、技术特征为广大机动车环保工作者所关注。为对在用汽车检测技术有一较全面的认识,本文对各种检测方法的要点进行阐述,同时介绍一些国内城市检测工作的研究和进展。  相似文献   
49.
We propose a method to simulate vehicle emissions in Chinese cities of different sizes and development stages. Twenty two cities are examined in this study. The target year is 2007. Among the cities, the vehicle emission factors were remarkably different (the highest is 50-90% higher than the lowest) owing to their distinct local features and vehicle technology levels, and the major contributors to total vehicle emissions were also different. A substantial increase in vehicle emissions is foreseeable unless stronger measures are implemented because the benefit of current policies can be quickly offset by the vehicle growth. Major efforts should be focused on all cities, especially developing cities where the requirements are lenient. This work aims a better understanding of vehicle emissions in all types of Chinese cities. The proposed method could benefit national emission inventory studies in improving accuracy and help in designing national and local policies for vehicle emission control.  相似文献   
50.
Introduction: Side impact crash injuries tend to be severe, mainly due to the effects of the mechanism of such crashes. This study addresses the relationship between side impact crash injury severities and side impact safety ratings of the passenger cars involved in such crashes. It is motivated by the lack of research on side impact safety ratings in relation to the real-world crash outcomes. Method: Analysis of Crashworthiness Data System’s (CDS) data show the head and thorax are the most common regions of impact of severe injuries, while the neck is the least. Irrespective of body regions, higher-rated vehicles were found to provide better occupant protection to both younger and older driver age groups. Assessment based on injury severity score (ISS) indicates that higher-rated vehicles have an overall lower average ISS compared to lower-rated vehicles. Results: Ultimately, this study shows that vehicles rated with National Highway Traffic Safety Administration’s (NHTSA) new criteria had lower average ISS compared to vehicles rated under the old criteria. The 2011 NHTSA side impact rating criteria being relatively new, it has very few crashes to draw meaningful statistically significant conclusions. However, this paper establishes the fact that vehicles with higher star ratings (under experimental conditions) indeed offer increased occupant protection in the field conditions. Practical applications: Previous studies have found that safety was given priority while buying new vehicles. However, people associated vehicle safety with technologies and specific safety features rather than the vehicle’s crash test results or ratings (Koppel, Charlton, Fildes, & Fitzharris, 2008). The results from this study provide a point of reference for safety advocates to educate the drivers about the importance of considering vehicle safety ratings during a vehicle purchase.  相似文献   
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