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751.
纯电动汽车驱动电机全生命周期评价 总被引:8,自引:2,他引:6
基于生命周期评价(LCA)理论,运用Ga Bi 6软件建模,对荣威E50纯电动汽车驱动电机全生命周期环境排放和资源消耗进行了评价,对比分析在中国不同区域使用下驱动电机生命周期过程资源环境影响,并对驱动电机生命周期过程中的生产制造能耗、使用能耗和原材料回收率做敏感性分析.结果表明,驱动电机全生命周期过程各环境影响类型指数排序为APGWPPOCPEPODP,且对环境的影响主要发生在使用阶段,其次是原材料获取和制造阶段.各大区域电网下驱动电机全生命周期过程环境排放影响从大到小为华东电网东北电网西北电网华北电网南方电网华中电网.从敏感性分析结果可知,使用能耗对驱动电机生命周期环境排放影响的敏感度大于生产制造能耗;铜的回收率对矿产资源消耗影响的敏感度远大于钢和铝的回收率. 相似文献
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Objective: In minicars, the survival space between the side structure and occupant is smaller than in conventional cars. This is an issue in side collisions. Therefore, in this article a solution is studied in which a lateral seat movement is imposed in the precrash phase. It generates a pre-acceleration and an initial velocity of the occupant, thus reducing the loads due to the side impact.Methods: The assessment of the potential is done by numerical simulations and a full-vehicle crash test. The optimal parameters of the restraint system including the precrash movement, time-to-fire of head and side airbag, etc., are found using metamodel-based optimization methods by minimizing occupant loads according to European New Car Assessment Programme (Euro NCAP).Results: The metamodel-based optimization approach is able to tune the restraint system parameters. The numerical simulations show a significant averaged reduction of 22.3% in occupant loads.Conclusion: The results show that the lateral precrash occupant movement offers better occupant protection in side collisions. 相似文献
754.
Objective: The Lower Anchor and Tethers for CHildren (LATCH) system was introduced in vehicles made after September 1, 2002 and intended to make installation of rear and forward-facing child safety seats easier. Due to the lack of rear impact testing of RFCRS required per the Federal Motor Vehicle Safety Standards (FMVSS), the purpose of this study was to explore the effects, if any, of installation method of RFCRS on the performance of commonly purchased makes and models of RFCRS. Specifically, we hypothesize that in a 48 km/h (29.8 MPH) rear-end collision, installation of RFCRS using the LATCH system will result in higher Head Injury Criteria (HIC) values when compared to using the available lap/shoulder seatbelt (Emergency Locking Retractor - ELR or Automatic Locking Retractor - ALR).Methods: The test matrix included 36 rear impact sled tests conducted using 3 installation methods on 3 models of RFCRS: the Graco SnugRide® with and without the base, the Britax Chaperone with base-mounted anti-rebound bar, and the Evenflo Tribute®, a model of convertible rearward/forward facing restraint system used in the rearward facing mode. The seats were installed using the LATCH system, ELR lap/shoulder belts, or ALR lap/shoulder belts in seating positions 4 and 6 on a vehicle buck mounted to the sled test base. The infant seat and 6 month old CRABI anthropometric test device (ATD) installation methods were in accordance with standards set forth in the National Highway Traffic Safety Administration's (NHTSA) FMVSS No. 213, Child Restraint Systems. All tests were conducted on pneumatic controlled acceleration sled (HYGE, Inc., PA, USA) at 48 km/h.Results: Installation of infant seat type RFCRS using the LATCH system resulted in higher HIC15 values when compared to using the available lap/shoulder seatbelt (ELR or ALR). The mean HIC15 values were most severe when infant seat type RFCRS were installed using LATCH (Graco SnugRide® HIC15 = 394 and Britax Chaperone HIC15 = 133) compared to using either ELR lap/shoulder belts (Graco SnugRide® HIC15 = 218 and Britax Chaperone HIC15 = 65) or ALR lap/shoulder belts (Graco SnugRide® HIC15 = 194 and Britax Chaperone HIC15 = 78). The installation method did not result in a statistically significant difference in HIC for the convertible type RFCRS (Evenflo Tribute®). In many of the tests, the ATD's head struck the seatback in which the RFCRS was installed. These head strikes resulted in the higher HIC15 scores recorded throughout the testing.Conclusions: The results of this study suggest that LATCH does not offer equal protection to lap/shoulder belts from head injuries in rear impacts when used with infant seat type RFCRS. 相似文献
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Xianbao Shen Zhiliang Yao Qiang Zhang David Vance Wagner Hong Huo Yingzhi Zhang Bo Zheng Kebin He 《环境科学学报(英文版)》2015,27(5):209-220
A database of real-world diesel vehicle emission factors, based on type and technology, has been developed following tests on more than 300 diesel vehicles in China using a portable emission measurement system. The database provides better understanding of diesel vehicle emissions under actual driving conditions. We found that although new regulations have reduced real-world emission levels of diesel trucks and buses significantly for most pollutants in China,NOx emissions have been inadequately controlled by the current standards, especially for diesel buses, because of bad driving conditions in the real world. We also compared the emission factors in the database with those calculated by emission factor models and used in inventory studies. The emission factors derived from COPERT (Computer Programmer to calculate Emissions from Road Transport) and MOBILE may both underestimate real emission factors, whereas the updated COPERT and PART5 (Highway Vehicle Particulate Emission Modeling Software) models may overestimate emission factors in China. Real-world measurement results and emission factors used in recent emission inventory studies are inconsistent, which has led to inaccurate estimates of emissions from diesel trucks and buses over recent years. This suggests that emission factors derived from European or US-basedmodels will not truly represent real-world emissions in China. Therefore, it is useful and necessary to conduct systematic real-world measurements of vehicle emissions in China in order to obtain the optimum inputs for emission inventory models. 相似文献
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应用受体模型(CMB)对北京市大气PM_(2.5)来源的解析研究 总被引:4,自引:0,他引:4
为研究影响北京市大气环境PM2.5污染水平的主要来源,于2012年8月—2013年7月,依托北京市大气地面观测网络在10个监测点采集的491 d(次)大气PM2.5有效样本,对其化学组分进行了测试分析;从城市大气污染源组成出发,建立和完善了5类固定点源、2类流动源、4类无组织面源的PM2.5排放成分谱.应用受体模型(CMB)开展了来源解析研究.结果显示:1观测期间大气环境PM2.5的来源主要包括:一次来源机动车(16%)、燃煤(15%)、土壤尘(6%)、二次硫酸铵和硝酸铵(36%),以及有机物(20%)和其他未识别来源(7%);与历史解析结果相比,燃煤源分担率有所下降,二次无机盐与有机物分担率上升,且二次硝酸盐有赶超二次硫酸盐之势;2从主要组分的来源看,观测期间环境大气PM2.5中近25%的硫酸盐来自于燃煤锅炉和电厂排放,17%的有机物来自机动车排放;3北京市PM2.5来源类型大致相同,但各点位PM2.5来源种类和分担率具有一定差异,对一些排放量较大的局地排放源有比较明确的响应.研究表明,开展区域性PM2.5治理、大力削减前体物、严格控制本地机动车、燃煤等PM2.5排放都是改善北京市空气质量的重要途径. 相似文献
760.
为研究电网较长时间停电环境下应急发电车与发电燃油供应协同优化调度问题,首先在电力公司管理现状基础上,通过对重要用户识别分析,按照是否自行配备发电机将重要用户进行分类,针对已经配备发电机的用户,重点考虑周期性供应燃油,对未配备发电机的用户,电力公司需紧急调度有限移动应急发电车,据此构建2阶段的移动应急发电车和油料供应模型以保证重要用户的紧急供电不会中断(第1阶段为电力公司应急发电车指派,第2阶段为加油站油料补充分配)。然后,将该调度问题转化为移动应急发电车指派问题和运油车路径问题的非线性混合模型,针对非线性目标函数和约束条件,通过引入大M法和变量替换进行线性化,得到混合整数线性规划,最小化负荷损失和成本为目标。最后,以某市电网重要用户为例,验证上述模型有效性,并通过原模型与聚类模型对比强调有限移动应急发电车的有效利用具备一定重要性。研究结果对电网公司保障应急供电具有重要指导意义。 相似文献