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11.
The present end-of-life vehicle (ELV) recycle rate and management status during the dismantling stage were investigated to aid the establishment of policies for the management of ELVs by surveying information and using the results gained from questionnaires given to dismantlers. The average recycle rate at the dismantling stage was 44% of the mass of a new vehicle and the rest of the ELV was then compressed and transported to shredding companies to recover mainly the iron content, which averaged 38.7% of the mass of a new vehicle. Nonferrous metals such as copper, antimony, zinc, and aluminum accounted for only 1.5%. The automobile shredder residues (ASRs) were composed of light and heavy fluffs and soil/dust and amounted to 15.8% based on the mass of a new vehicle. The dumping of fluff and inorganic residues in landfill sites, however, will be restricted when new regulations are implemented to reduce the disposal amount to less than 5% of a new car, as has been done in European countries and in Japan. The detailed characteristics of ASR were investigated to suggest appropriate means of treatment such as volume reduction or the utilization of thermal technologies to meet future expected enforcement. Also, some concerns on hazardous pollutant release such as that of dioxins while utilizing such thermal treatment methods were considered. The present on-going research and development projects to meet such future management targets are also introduced.  相似文献   
12.
The body of information presented in this paper is directed to air pollution engineers who are concerned with the effect of indirect sources on ambient concentrations of carbon monoxide (CO). Data taken under controlled conditions are used to empirically derive and calibrate a model for predicting CO concentrations in the vicinity of roadway intersections and other points of possible vehicular congestion. Since the predicted free flow CO contribution of vehicles traveling at normal road speeds is relatively low, it is concluded that idling vehicles at points of congestion are the major cause of CO violations, and that state and federal programs should place more emphasis on relieving congestion and reducing idling emission rates in new vehicles.  相似文献   
13.
针对我军当前装甲车辆鉴定定型试验中,沙漠戈壁地区适应性试验考核试验覆盖度较低、考核强度不足、试验标准老旧等问题,导致作战效能大幅下降,甚至无法满足作战使用要求。在参照当前传统的严寒、湿热、高原地区适应试验组织方法基础上,结合当前复杂环境试验及边界条件考核要求,分析了沙漠戈壁地区敏感环境因素,提出了2种新型试验方法,一是“基础+复杂”组合的沙漠戈壁地区适应性试验方法,二是基于作战使用任务剖面循环的试验方法,进一步提升试验考核强度及深度,为装甲车辆沙漠戈壁地区适应性试验开展提供了设计新思路。  相似文献   
14.
依据城市机动车空气污染评价方法确立了天津市空气污染物机动车污染的评价体系。该评价体系具有准确性、先进性和实用性,采用科学的方法估算天津市城区机动车排气污染物的排放浓度及总量对环境空气污染的分担率。科学地给出了天津市现阶段机动车污染的现状及发展趋势,为环境保护决策提供了科学依据。  相似文献   
15.
As the production of local vehicles increases, the impact of end-of-life vehicles (ELVs) wastes to the environment will also increase. ELVs recovery including reuse, remanufacture, and recycle apparently become a strategy in solving this environmental problem. This study identifies the existing conditions of automotive reuse in Malaysia by conducting some interviews in selected local automotive and automotive component manufacturers. Results from the interviews indicated that reuse of automotive components in newly manufactured vehicles has never been practiced by the selected companies. However, there is interest among respondents in developing automotive components for after-market reuse. Some strategies were proposed in this study to initiate automotive components reuse in the local automotive manufacturers including the establishment of the end-of-life directive, enhance research and development on design for reuse and increase reusability and economic benefits of reuse.  相似文献   
16.
Introduction: The appearance of musculoskeletal disorders (MDs) in professional drivers due to exposition to whole-body vibration (WBV) makes it relevant to assess this exposure. The European Directive 2002/44/EC has two methods to evaluate exposure to WBV (defined in ISO2631-1:2008). These methods evaluate the exposure associated with an 8-hour working day; however, MDs due to WBV could also be caused by accumulated exposure to vibrations over long term, and hence, the methods defined in the European directive may be limited in their ability to ensure the safety of workers exposed to WBV throughout their years of employment. Method: A detailed comparison and discussion of methods defined in the European Directive and the ISO2631-5:2018 was used as a starting point of the main results of this paper. On this basis, a new methodology for the management and organization of preventive measures is proposed to consider the assessment of ISO2631-5:2018 standard and the full working life of workers. Experimental data to assess exposure to WBV in heavy equipment vehicle (HEV) drivers under different road surface conditions and range of velocities were considered to illustrate the process of the proposed methodology. Results: The methods defined in the standards provide different assessments leading to a different possible consideration of safe operations when the risks associated with them may actually be high. The proposed methodology can be used with the aim of ensuring safety of workers throughout their working lives and providing an easy implementation of the calculations of ISO2631-5:2018 standard. Conclusions: A procedure to assess the health risk probability to which the HEV worker is exposed in terms of the exposure years and a different range of operational vehicle speeds is proposed and exemplified with a study case. Practical applications: This study provides a practical tool for the management of WBV exposure related to work-tasks in HEV drivers. Safety managers should consider the global exposition to WBV throughout their working life, and this research provides an easy tool to accomplish it.  相似文献   
17.
Objectives: The objective of this study was to examine the association between dangerous student car drop-off behaviors and historical child pedestrian–motor vehicle collisions (PMVCs) near elementary schools in Toronto, Canada.

Methods: Police-reported child PMVCs during school travel times from 2000 to 2011 were mapped within 200 m of 118 elementary schools. Observers measured dangerous student morning car drop-off behaviors and number of children walking to school during one day in 2011. A composite score of school social disadvantage was obtained from the Toronto District School Board. Built environment and traffic features were mapped and included as covariates. A multivariate Poisson regression was used to model the rates of PMVC/number of children walking and dangerous student car drop-off behaviors, adjusting for the built environment and social disadvantage.

Results: There were 45 child PMVCs, with 29 (64%) sustaining minor injuries resulting in emergency department visits. The mean collision rate was 2.9/10,000 children walking/year (SD = 6.7). Dangerous drop-off behaviors were observed in 104 schools (88%). In the multivariate analysis, each additional dangerous drop-off behavior was associated with a 45% increase in collision rates (incident rate ratio [IRR] = 1.45, 95% confidence interval [CI], 1.02, 2.07). Higher speed roads (IRR = 1.27, 95% CI, 1.13, 1.44) and social disadvantage (IRR = 2.99, 95% CI, 1.03, 8.68) were associated with higher collision rates.

Conclusions: Dangerous student car drop-off behaviors were associated with historical nonfatal child PMVC rates during school travel times near schools. Some caution must be taken in interpreting these results due small number of events and limitations in the data collection, because collision data were collected historically over a 12-year period, whereas driving behavior was only observed on a single day in 2011. Targeted multifaceted intervention approaches related to the built environment, enforcement, and education could address dangerous drop-off behaviors near schools to reduce child PMVCs and promote safe walking to school.  相似文献   

18.
To overcome adoption barriers and promote battery electric vehicles (BEVs) as an energy efficient consumer transportation option, a number of states offer subsidies to consumers for BEVs. We use a national data set of vehicle registrations and state-level financial incentives to assess the impact of vehicle purchase subsidies on adoption using both difference-in-differences and synthetic controls methods. We find that incentives offered as direct purchase rebates generate increased levels of new BEV registrations at a rate of approximately 8 percent per thousand dollars of incentive offered. Between 2011 and 2015, vehicle rebate incentives are associated with an increase in overall BEV registrations of approximately 11 percent. Our findings indicate incentives offered as state income tax credits do not have a statistically significant effect on BEV adoptions, though we caution this may be a result of limited temporal variation in BEV incentives across our sample. Responses to rebate incentives do not differ significantly by the make of the vehicle purchased (i.e., Tesla and non-Tesla vehicles). We combine our results with recent assessments of marginal environmental costs of electric vehicle charging and measure net welfare effects of BEV subsidy programs. Our analysis indicates these programs are not welfare-improving if only considering benefits associated with avoided emissions. Additional benefits associated with long-term market growth, production cost savings, network externalities, or accelerated innovation could substantially impact the net welfare outcomes.  相似文献   
19.
广州市移动源现状及其污染控制管理对策   总被引:6,自引:0,他引:6  
通过对广州市机动车辆构成状况和发展趋势、车流变化与氮氧化物变化关系以及各类车型污染排放分担率的分析,结果表明:在排放污染物的移动源中,小型车(出租车及其他小型车)和摩托车是一氧化碳、碳氢化合物的主要排放源;公共汽车等大型车是氮氧化物的主要排放源之一。并提出对广州市机动车污染控制应着重控制摩托车、小型车(特别是轿车,包括出租车)、公共汽车的污染排放。   相似文献   
20.
How consumers might switch from gasoline and diesel to alternative energy sources is not known, since the availability of alternatives is currently very limited. To bridge this gap, we exploit exogenous variation in ethanol prices at Brazil's pumps and uncover substantial consumer heterogeneity in the choice between long-established gasoline and an alternative that is similarly available and usable: sugarcane ethanol. We observe roughly 20% of flexible-fuel motorists choosing gasoline when gasoline is priced 20% above ethanol in energy-adjusted terms ($/mile) and, similarly, 20% of motorists choosing ethanol when ethanol is priced 20% above gasoline. We use transaction-level data to explore “non-price” characteristics which differentiate the two goods in the minds of different groups of consumers. Our findings suggest—and a counterfactual illustrates—that switching away from gasoline en masse, should this be desired, would require considerable price discounts to boost voluntary adoption, in the US and elsewhere.  相似文献   
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