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51.
Governments in the US spend over a hundred billion dollars per year to build and maintain roads and provide a variety of services for motor-vehicle users. To pay for these infrastructure and services governments collect revenue from a variety of taxes and fees. The basic objective of this paper is to compare these government expenditures with the corresponding user tax and fee payments in the US. At the outset I argue that the such comparisons tell us something about the equity but not necessarily the economic efficiency of highway financing. I then present four different ways one might tally up government expenditures and user payments, depending on the extent to which one wishes to count “indirect” expenditures (e.g., on prosecuting car thieves) and non-targeted general-tax payments (e.g., severance taxes on oil). I make a comprehensive analysis of all possible expenditures and payments, and then compare them according to three of the four ways of counting expenditures and payments. The analysis indicates that in the US current tax and fee payments to the government by motor-vehicle users fall short of government expenditures related to motor-vehicle use by approximately 20–70 cents per gallon of all motor fuel. (Note that in this accounting we include only government expenditures; we do not include any “external” costs of motor-vehicle use.) The extent to which one counts indirect government expenditures related to motor-vehicle use is a key factor in the comparison.  相似文献   
52.
马义  刘鑫  李金龙  谢亮 《天津汽车》2010,(11):40-42
车载自动诊断系统(OBD)是实行国Ⅲ和国Ⅳ排放标准的核心内容,汽油机失火诊断是OBD的一个重要功能。指出了汽油机失火的原因和危害,分析了汽油机失火检测的3种方法,建立了TU5JP4汽油机曲轴转速检测法的GT—Power仿真模型。结果表明:汽油机失火时,转速和扭矩都会出现短时间的下降,其中扭矩下降更为明显,同时排气中O2浓度升高,CO2的浓度下降。将GT—Power软件应用于发动机失火故障模拟,对失火诊断系统的开发有较好的指导作用。  相似文献   
53.
车用乙醇汽油对发动机进气系统沉积物的影响   总被引:6,自引:0,他引:6  
郭瑞莲  鲍晓峰  岳欣  崔平  纪威 《汽车工程》2007,29(8):642-644,691
通过12 000km道路行车试验及M111发动机台架试验,对比研究乙醇汽油与普通无铅汽油对发动机进气系统沉积物的影响;同时,在M111发动机实验台架上,还对加入清净剂后的乙醇汽油与普通无铅汽油进行了进气阀沉积物与总燃烧室沉积物的实验研究。结果显示:乙醇汽油进气系统沉积物较为严重,应加入有效的汽油清净剂。  相似文献   
54.
采用比较的方法,研究了醇类汽油对炭罐工作能力、脱附特性和残存特性的影响;通过对油箱进行昼间呼吸试验,研究了醇类汽油对蒸发排放量的影响;通过整车蒸发排放试验以及色谱分析试验研究,验证了目前的蒸发排放控制系统对醇类汽油的适应性。  相似文献   
55.
肖琼  颜伏伍  邹华 《汽车工程》2006,28(3):235-237
介绍所设计的电控喷油器喷雾特性测试系统的组成及原理,该系统能够对喷油器的喷雾锥角和喷雾均匀性这两个评价喷油器性能的重要指标进行准确的测量。对某一型号喷油器的喷雾特性进行测试和分析。  相似文献   
56.
混合动力汽车汽油机电子节气门模糊智能PID控制   总被引:1,自引:0,他引:1  
应用英飞凌新一代车用嵌入式控制芯片XC164,开发了基于模糊智能积分PID复合控制算法的混合动力汽车汽油机电子节气门控制系统,为混合动力汽车主控制器和发动机控制之间提供了控制接口。通过对混合动力轿车进行的实际行驶中频繁急加速、急减速过程中电子节气门目标开度和实际控制开度的对比试验,验证了电子节气门控制响应速度快、稳态误差小及控制系统软硬件设计满足混合动力总成对发动机控制的要求。  相似文献   
57.
于秀敏  陆孝宽 《汽车工程》1994,16(4):214-218
本文介绍应用MCS-51系列8031单片机研制的一套汽油喷射系统开发装置,该装置可对汽车油喷射系统,汽油喷系统与发动机的匹配以及发动机的控制方法等进行研究,具有简单,实用,可靠,低价以及测量准确等优点。  相似文献   
58.
Electric versus conventional vehicles: social costs and benefits in France   总被引:1,自引:0,他引:1  
This article compares the social costs of electric vehicles with those of conventional, thermal vehicles for typical passenger use in the Ile-de-France region (Greater Paris), a case of particular interest because nearly 80% of the electricity is generated by nuclear power plants. A four-seat electric car is compared to a new conventional car of the same make and model; for the latter both the gasoline and the diesel version are considered because almost half of new car sales in France are diesel. These results are also compared to typical existing diesel and gasoline vehicles in the current French fleet. The methodology developed by the ExternE (External Costs of Energy) Project of the European Commission is used to estimate the costs associated with atmospheric pollution due to power plants, refineries and tail pipe emissions. Our discussion of externalities is limited to air pollution thus excluding others such as costs associated with noise or accidents. Our results imply that the external costs are large and significant, even when one considers the uncertainties. If internalized by government regulations, these externalities can render the total cost of an electric vehicle more competitive with that of currently available thermal vehicles in large urban centers if the electricity is produced by sources with low pollution. However, the current generation electric vehicles are so expensive that internalization of pollution damage would not give it a very clear advantage.  相似文献   
59.
The objective of the present study is the assessment of the environmental impact of a bivalent (bi-fuel) vehicle, running either on gasoline or compressed natural gas (CNG). To that aim, a Euro 6 passenger car was tested under various real-world driving conditions. In order to cover the full range of conventional powertrains currently in the market, the tests were also repeated on a Euro 6 diesel passenger car. Both cars were driven in two routes, the first complying with the regulation limits and the second going beyond them. Carbon monoxide (CO), nitrogen oxides (NOx) and particle number (PN) emissions were recorded using a Portable Emissions Measurement System (PEMS). Apart from the aggregated emission levels, in g/km, the exact emission location along the route was also assessed. Natural gas proved beneficial for CO and PN emissions, the level of which always remained below the respective legislation limits. On the other hand, under the dynamic driving conditions with gasoline, the relevant limits were exceeded. Cold start, occurring at the beginning of the urban part, and motorway driving were identified as major contributors to total emissions, especially in gasoline mode. However, the application of natural gas was associated with a penalty in NOx emissions, which were significantly increased as compared to gasoline. Local peaks within the urban part were identified in CNG mode. In any case, the diesel vehicle was by far the highest NOx emitter.  相似文献   
60.
针对某均质缸内直喷汽油机低速时燃油湿壁问题,用定容弹试验对喷雾模型进行标定,同时使用FIRE 软件对单段和两段喷油策略的混合气形成过程进行数值模拟研究.结果表明,转速为2000 r/min的全负荷工况下,单段喷油时燃油湿壁现象较为严重,而采用两段喷油可明显改善燃油碰壁情况,且点火时刻缸内混合气均匀性也得到改善;第2段喷油结束时刻越晚,燃油碰壁量越小,混合气浓度分布均匀性越差.  相似文献   
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