尾气分析与汽油发动机系统故障诊断

汽油发动机尾气成分直接与发动机的工作情况有关,对发动机在不同工况下尾气中不同成分气体含照的检测和分析,可以判断发动机各系统工作是否正常,也可以据此埘汽油发动机系统进行故障诊断。本文介绍利用尾气分析结果对发动机各系统进行故障诊断的方法。     

港口粉尘污染防治技术研究进展

综述了港口粉尘污染现状、常用防治方法,在此基础上对港口粉尘防治的前沿技术——防风网、煤筒仓、煤炭防尘水分自动化管理系统进行了详细的介绍。     

长江流域航运与水环境协调发展模型

为促进长江流域航运与水环境的协调发展, 利用系统分析方法和系统动力学模型, 建立了长江流域航运与水环境协调发展模型, 对各种宏观调控政策和措施效应进行了仿真模拟分析。模拟结果表明, 计算指标模拟值与实际值基本吻合, 最大相对误差为12.9%, 表明模型能较好地模拟长江流域航运与水环境协调发展系统; 航运污染主要来源于船舶事故污染和船员生活污染, 占总污染90%以上; 人口、水环境、航运及工农业协调增长模式有助于水环境质量的持续改善; 船舶事故应急管理水平的提高是航运污染治理的关键。     

城市交通发展过程中的环境问题及对策研究

交通污染已经成为我国城市空气和噪声的主要污染源,严重影响了城市的经济发展和居民的生活质量。用牺牲环境及资源来解决交通问题是城市交通发展的一大误区。该文在分析城市交通污染现状的基础上,从可持续发展的角度,按照以人为本的理念,提出了治理交通污染的宏观政策与具体对策。     

河流突发性污染事故风险评价方法的探讨

通过危险源和环境因素两个方面进行河流突发性污染事故风险评价,引入加权危险河段长度和河段危害权重两个概念论述危险源风险评价,给出能够反映各河段重要性的新的危险源风险评价方法。评价了流速、降水、地形等自然环境因素对突发性水污染事故发展的影响,提出了环境因素定性评价方法。     

船长文献--远洋船进入美国水域操作指南(一)

系统而详尽地介绍了美国海岸警备队(USCG)对船舶检查的特点,以及船舶为适应USCG要求而应该采取的对策。     

Hierarchal assessment of noise pollution in urban areas – A case study

Noise pollution in urban areas has many harmful effects on the citizens. There are varieties of noise generation sources of which the traffic noise could be a major source. The point which is perhaps less noticed is that sound level is not the only parameter to indicate the extent and intensity of noise pollution. Situation of urban land uses, distribution of population centers and types of passages can deeply affect the concern on this environmental issue but not with a similar ratio. This article presents an overlaying technique to define noise prone areas using all different factors involved. A case study was carried out in the District 14 of Tehran Metropolitan City where there are busy streets and highways. For this purpose, the share of each criterion in noise pollution intensity was determined using Analytical Hierarchy Process (AHP). Afterwards, the map layers were overlaid based upon the relative importance of the criteria to get the final map on which the noise prone areas are specified. The developed method could be used as a tool for indirect estimation of noise pollution by which instead of direct measurement of the equivalent sound level, it would be possible to predict noise susceptible areas considering the most important influential factors.     

Congestion and pollution consequences of driving-to-school trips: A case study in Beijing

Parents compete for high-quality education for their children by enrolling them in good schools. However, in a Chinese mega-city like Beijing, three factors jointly lead to the spatial separation between schools and homes: the centralized public goods provision mechanism, the historical dependency in school location, and the constrained supply of housing in downtown. Without an adequate number of school buses, this spatial separation of schools and homes triggers the numerous long-distance driving-to-school trips by private vehicle during workday morning rush hours in Beijing. We use the start and end dates of “school holiday” as exogenous repeated shocks to the aggregate traffic congestion, and employ the two-stage least squares (2SLS) regression approach to examine the congestion and pollution consequences of such driving-to-school trips in Beijing. We find that, all else being equal, workdays during school holidays have a traffic congestion index 20% lower than that of non-school-holiday workdays. Such a sharp reduction in congestion leads to a significant decrease in PM₁₀ concentration. Policymakers should lower such “extra” congestion and environmental costs via optimizing the spatial balance between school supply and demand.     

Going fast or going green? Evidence from environmental speed limits in Norway

This paper studies the impact of speed limits on local air pollution using a series of date-specific speed limit reductions in Oslo over the 2004–2011 period. We find that lowering the speed limit from 80 to 60 km/h reduces travel speed by 5.8 km/h. However, we find no evidence of reduced air pollution as measured next to the treated roads. Our estimates suggest an annual time loss of the speed limit reductions of 66 USD per affected vehicle. Our findings imply that policy makers need to consider other actions than speed limit reductions to improve local air quality.     

摆盘机水下排气噪声的研究

本文对摆盘式发动机气液脉动两相流水下排气噪声的形成过程和影响因素进行了理论和实验研究，给出了控制水下排气噪声的主要技术途径，并进行了初步实验验证。