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911.
浙江省机动车主要污染物减排是"十二五"大气主要污染物减排的重要组成部分,为完成国家下达的机动车主要污染物减排目标,根据浙江省机动车保有量及污染物排放量现状,预测"十二五"期间机动车增长带来的污染物排放情况,着重分析影响浙江省机动车氮氧化物排放量的关键因素,并从淘汰"黄标车"、提高油品质量和加强管理等方面提出相应减排对策,分析浙江省机动车主要污染物的减排可达性。  相似文献   
912.
环境保护部日前发布《2013年中国机动车污染防治年报》,公布了2012年全国机动车污染排放状况..本期“研究成果展示”专栏以六篇形式连载。本文刊载2012年全国机动车保有量及其变化趋势的内容,以飨读者。该年报指出,(1)2012年,全国机动车保有量2.24亿辆。其中汽车10837.8万辆,低速汽车1145.0万辆,摩托车10400.0万辆。,与往年不同,汽车保有量已超过摩托车保有量,占主导地位..(2)2012年,全国汽车保有量10837.8万辆。其中,按车型分类,客车占82.5%,货车占17.5%;按燃料类型分类,汽油车占82.5%,柴油车占16.1%,燃气车占1.4%;按排放标准分类,国I前标准的汽车占7.8%,国I标准的汽车占14.9%,国Ⅱ标准的汽车占15.7%,国Ⅲ标准的汽车占51.5%,国Ⅳ及以上标准的汽车占10.1%;按环保标志分类,“黄标车”占13.4%,“绿标车”占86.6%..(3)2010—2012年全国机动车保有量呈快速增长态势,由19(106.2万辆增加到22382.8万辆,年均增长8.5%。其中,汽车保有量由7721,7万辆增加到10837.8万辆,年均增长18.5%;“黄标车”保有量由1558.3万辆降低到1451.4万辆,年均削减3.5%.  相似文献   
913.
环境保护部目前发布《2013年中国机动车污染防治年报》,公布了2012年全国机动车污染排放状况。本期“研究成果展示”专栏以六篇形式连载。本文刊载关于全国机动车氮氧化物总量减排的内容,以飨读者。  相似文献   
914.
Mechanical defects of a vehicle driving system can be dangerous on the road. Diagnostic systems, which monitor operations of electric and electronic elements and devices of vehicles, are continuously developed and improved, while defects of mechanical systems are still not managed properly. This article proposes supplementing existing on-board diagnostics with a system of diagnosing selected defects to minimize their impact. It presents a method of diagnosing mechanical defects of the engine, gearbox and other elements of the driving system on the basis of a model of the vibration signal obtained adaptively. This method is suitable for engine valves, engine head gasket, main gearbox, joints, etc.  相似文献   
915.
To verify the effectiveness of a new automatic sorting technique that combines a weight meter and a laser 3D shape-detection system, elemental analysis of lightweight metal scraps generated in end-of-life vehicle (ELV) shredder facilities was conducted using a handheld XRF analyzer. According to their 3D shape and chemical composition, aluminum scraps were classified into cast alloy (Alc) and wrought alloy (Alw) fragments, and magnesium scraps were classified into irregularly shaped and rod-like fragments. The average chemical composition of a group of fragments was estimated before and after the separation test using the developed automatic sorting technique. The results show that the production of wrought aluminum alloy from the mixture of Alc and Alw fragments is not realistic because the contents of some alloying elements greatly exceed the standard values, although these alloying elements greatly decrease after the Alc fragments are separated out. For the magnesium scraps, after the rod-like magnesium fragments originating from the steering column were separated from the irregularly shaped fragments, the average chemical compositions of the rod-like products and the irregularly shaped products clearly approached the standard compositions of AM60B and AZ91D alloys, respectively. Thus, it was confirmed that the developed automatic sorting technique contributes to recycling of lightweight metal scrap in the automobile industry.  相似文献   
916.
本文以整车道路腐蚀试验数据为基础,介绍了常见腐蚀部位,阐述了影响腐蚀的相关因素。此外,通过防腐工艺对比,提出防腐优化建议。  相似文献   
917.
Period vehicle routing, a multi-period extension of the capacitated vehicle routing problem, is the problem of determining a service combination of each customer as well as the vehicle routes in each period of the planning horizon while satisfying the restrictions on the vehicle capacity and the travel distance (time). The problem can typically be found in refuse collection systems in which end-of-life products or wastes are collected and moved to the facilities where further treatment is taken care of. In this study, we report a case study on the problem for the objective of minimising the fleet size, i.e. the maximum number of vehicles simultaneously required over the planning horizon. To solve the problem, we adopt the two-stage heuristic in which an initial solution is obtained by assigning a service combination to each collection point, and then it is improved by changing the service combination assigned to each collection point. Computational experiment was done on the case data and significant improvement over the conventional method is reported.  相似文献   
918.
Objectives: Motor vehicle crashes remain a leading cause of death in the United States (US). Thoracic aortic dissection due to blunt trauma remains a major injury mechanism, and up to 90% of these injuries result in death on the scene. The objective of this study is to understand the modern risk factors and etiology of fatal thoracic aortic injuries in the current US fleet.

Methods: Using a unique, linked, Fatality Analysis Reporting System (FARS) and Multiple Cause of Death (MCOD) database from 2000–2010, 144,169 drivers over 16 years of age who suffered fatal injuries were identified. The merged database provides an unparalleled fidelity for identifying thoracic aortic injuries due to motor vehicle accidents. Thoracic aortic injuries were defined by ICD-10 codes S250. Univariate and multivariate logistic regression models for presence of any thoracic aortic injuries were fitted. Age, gender, BMI weight categories, vehicle class, model year, crash type/direction, severity of crash damage, airbag deployment location, and seatbelt use, fatal injury codes, and location of injury were considered. Odds ratios (OR) and corresponding 95% confidence intervals (95%CI) are calculated.

Results: There were 2953 deaths (2.10%) related to thoracic aortic injuries that met the inclusion criteria. Nearside crashes were associated with an increased odds (OR = 1.42, 1.1-1.83), while rollover crashes (OR =.44,.29-.66) were associated with a reduced odds of fatal thoracic aortic injury. Using backward selection on the full multivariate model, the only significant model effects that remained were vehicle type, crash type, body region, and injury type.

Conclusions: The increased prevalence of fatal thoracic aortic injury in nearside crashes, increasing age, and vehicle type provide some insight into the current US fleet. Important factors, including model year, had significantly lower levels of the injury in univariate analysis, demonstrating the effect of safety improvements in newer model vehicles. Further study of this fatal injury is warranted, including comparisons of those who survive the injury.  相似文献   

919.
Introduction: Restraint systems (seat belts and airbags) are important tools that improve vehicle occupant safety during motor vehicle crashes (MVCs). We aimed to identify the pattern and impact of the utilization of passenger restraint systems on the outcomes of MVC victims in Qatar.

Methods: A retrospective study was conducted for all admitted patients who sustained MVC-related injuries between March 2011 and March 2014 inclusive.

Results: Out of 2,730 road traffic injury cases, 1,830 (67%) sustained MVC-related injuries, of whom 88% were young males, 70% were expatriates, and 53% were drivers. The use of seat belts and airbags was documented in 26 and 2.5% of cases, respectively. Unrestrained passengers had greater injury severity scores, longer hospital stays, and higher rates of pneumonia and mortality compared to restrained passengers (P = .001 for all). There were 311 (17%) ejected cases. Seat belt use was significantly lower and the mortality rate was 3-fold higher in the ejected group compared to the nonejected group (P = .001). The overall mortality was 8.3%. On multivariate regression analysis, predictors of not using a seat belt were being a front seat passenger, driver, or Qatari national and young age. Unrestrained males had a 3-fold increase in mortality in comparison to unrestrained females. The risk of severe injury (relative risk [RR] = 1.82, 95% confidence interval [CI], 1.49–2.26, P = .001) and death (RR = 4.13, 95% CI, 2.31–7.38, P = .001) was significantly greater among unrestrained passengers.

Conclusion: The nonuse of seat belts is associated with worse outcomes during MVCs in Qatar. Our study highlights the lower rate of seat belt compliance in young car occupants that results in more severe injuries, longer hospital stays, and higher mortality rates. Therefore, we recommend more effective seat belt awareness and education campaigns, the enforcement of current seat belt laws, their extension to all vehicle occupants, and the adoption of proven interventions that will assure sustained behavioral changes toward improvements in seat belt use in Qatar.  相似文献   

920.
中国城市轻型车的排放特性   总被引:4,自引:2,他引:2  
采用机动车实际上路排放测试系统对北京、重庆和成都3城市27辆轻型车进行了测试和分析;采用发动机比功率VSP、发动机负荷ES和排放单元BIN分析了轻型车瞬态排故的特征及影响排放的主要因素.结果表明.发动机技术和累计行驶里程对排放的影响很大,而VSP等概念还反映了道路坡度对排放因子的影响;由于城市道路坡度的差异,导致同一测试车辆在重庆和成都2个城市的排放水平相差10%~100%.  相似文献   
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