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81.
PROBLEM: Although parking facilities are a common feature of the landscape in the United States, little is known about their safety. METHOD: A dataset of parking lot fatalities for 1993-2002, created from the Census of Fatal Occupational Injury (CFOI) research file, was analyzed. RESULTS: The most common events in parking lots were contact with objects (15%), pedestrian fatalities (13%), homicides (36%), and suicides (11%). The perpetrators of parking lot fatalities, compared to all workplace homicides, were more likely to be known to the victim. CONCLUSION: The 206 work-related fatalities per year in parking lots present challenges to the safety community. Although much of the risk results from the usage of motor vehicles, violent acts are even more prominent. IMPACT ON INDUSTRY: Because homicides are most prevalent in parking lots, both administrative and environmental measures may lower the risk of homicide. Although difficult to assess, various elements of the design of parking facilities may have an influence on the occurrence of injuries.  相似文献   
82.
采用过滤分离、超声洗脱和气质联用等技术,实验测定了柴油机尾气中碳烟颗粒物的质量含量、可溶性有机组分在颗粒物中的质量分数和可溶性有机组分的化学组成。在实验条件下,柴油机尾气中碳烟颗粒物的质量含量为32·6~143·6mg/m3。可溶性有机组分在颗粒物中的质量分数为18·5%~89·4%。可溶性有机组分中检测出有机物100多种,已确定化学结构的有机物73种,其中直链和支链烷烃含量占81·22%,芳烃类化合物17·94%。  相似文献   
83.
Mechanical recycling of 100% post-consumer plastic waste into high-quality products has been performed. The chemical and physical properties of these recycled materials have been compared with similar products manufactured from virgin resins. The properties of a blow-moulded bottle prepared from 100% post-consumer high-density polyethylene (HDPE) showed that this recycled polymer exceeded the materials specifications for virgin plastic designs. Similarly, a sample of thermoplastic polyolefin (TPO, 100% polypropylene), obtained entirely from shredder residue (SR) displayed sufficient material strength for future separation and reprocessing.  相似文献   
84.
在分析城市步行街及其周边存在人车混行、人员密度高、通行效率低、潜在的危险大的基础上,笔者用计算机模拟方法研究了沈阳市中街步行街的一个人车混行的交叉路口,实际勘察了十字路口道路格局、车流、人流状况,测量、估计通过路口的人数、流量,根据获得的数据,对不设置交通信号灯、设置信号灯、建设过街天桥或地下通道等几种情况进行模拟,得到各种情况下的通行效率,并对不同的过街方案的优缺点进行比较。最终选择过街方案需要综合考虑影响安全和效率的多种因素,包括地域、人流量、路口宽度、周边交通等因素,用较小的经济投入取得最大的通行效率。文中的模拟采用EXODUS软件。  相似文献   
85.
交通来源颗粒物排放因子的研究   总被引:11,自引:1,他引:10  
用谭裕沟隧道TSP,PM10和PM2.5的质量浓度和主要成分的分析结果,得到一定机动车流量和速度下交通来源不同粒径颗粒物质量浓度和主要成分的平均排放因子,可以基本代表北京市机动车行驶的综合排放因子,具有应用价值.还估算了北京市交通来源不同粒径颗粒物及其主要化学成分的排放量.   相似文献   
86.
The concentrations of semi-volatile polycyclic aromatic hydrocarbons (PAHs), hydrocarbons (HCs), particulate matter (PM 1, 2.5 and 10 μm) and total suspended particles (TSPs) were measured in a traffic tunnel in Gothenburg, Sweden. Emission factors (EFs) were also calculated. These variables are assumed to provide good estimates of average vehicle emissions, since all types of vehicle, using all types of fuel, pass through this tunnel. It was shown that the majority of particle-associated PAHs were found on particles with an aerodynamic diameter of <1 μm. The concentrations of PAHs were one order higher in magnitude in air samples from the tunnel than in air samples at two urban locations. However, the PAH profiles of air samples from the tunnel and the urban sites were similar. This was demonstrated using principal component analysis (PCA). Finally, and notably, there was no significant change in the total emissions when the proportion of heavy-duty vehicles (HDVs) increased from 8% to 24%. Previously, diesel vehicles had been found to release larger quantities of PAHs and related substances. Advances in fuel quality, and HDV motor and exhaust system design during the last decade may have contributed to this promising result. However, it was shown, using partial least squares regression to latent structures (PLS), that some of the parameters measured displayed correlations with the proportions of HDVs and light-duty vehicles (LDVs). Concentrations of total HCs, TSPs, dibenzothiopene, phenantrene, anthracene and monomethyl-derivatives of phenantrene and anthracene were all correlated to the proportion of HDVs. The concentrations of naphthalene, some mono- and dimethylnaphthalenes and most large PAHs (with 5–7 fused rings) were correlated to the proportion of LDVs.  相似文献   
87.
机动车尾气净化控制的一个难点在于冷启动阶段,此时由于温度较低,催化剂尚未完全起作用,导致排出的污染物浓度较高。阐述了活性炭纤维的基本特性,特别是其低温吸附与催化性能对NO和CO的转化作用,讨论了活性炭纤维作为机动车尾气净化材料所需的改性及方法,并展望了其应用前景。  相似文献   
88.
To improve the estimation accuracy of battery’s inner state for battery management system, an online parameters identification algorithm for Thevenin battery model is researched. The Thevenin model and parameters identification algorithm based on recursive least square adaptive filter algorithm was built with the Simulink/xPC Target. The results of hardware-in-loop experiment, which uses Federal Urban Driving Schedule test to verify the parameters identification approach, show the proposed approach can accurately identify the model parameters within 1% maximum terminal voltage estimation error, and the State of Charge error which calculated by the open circuit voltage estimates can be efficiently reduced to 4%.  相似文献   
89.
2014年9月1日起,国家试行6年以内的非营运轿车等车辆免检制度。大多数城市根据此规定,对于车辆的排放定期检验也同步实施6年免检。随着汽车保有量的快速增长,车辆尾气排放对大气环境的影响不容忽视。因此,地方环保部门应针对机动车污染排放的管理重点,从管理手段、管理体制机制、管理对策等方面进一步加强对高污染车辆的监管。  相似文献   
90.
为完善增程式电动汽车(Extended range electric vehicle,EREV)全生命周期环境影响和经济效益评价研究,对EREV、纯电动汽车(Battery electric vehicle,BEV)和内燃机汽车(Internal combustion engine vehicle,ICEV)进行了对比分析.基于生命周期评价理论和生命周期成本分析方法,构建了车辆生命周期资源消耗、能源消耗、环境影响和成本评价模型,针对不同汽车各阶段材料消耗、能源消耗和环境排放三大特性,识别EREV、BEV和ICEV的环境负荷差异,并从初始购置成本、使用维护成本和报废回收成本3个方面评价了EREV、BEV和ICEV的生命周期成本差异.综合碳排放特性和经济属性,进一步提出减碳经济性评价指标,科学评价EREV和BEV的环境效益和减碳经济性,并讨论了不同电力结构下EREV、BEV和ICEV的生命周期温室气体排放情况和减碳经济性变化.对增程式电动汽车进行全生命周期内综合评价研究,进一步明确EREV在多种能源类型汽车技术路线中的环境效益和减碳经济性.结果表明,相比于ICEV,BEV和EREV在运行使...  相似文献   
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