Deciphering urban traffic impacts on air quality by deep learning and emission inventory

Air pollution is a major obstacle to future sustainability, and traffic pollution has become a large drag on the sustainable developments of future metropolises. Here, combined with the large volume of real-time monitoring data, we propose a deep learning model, iDeepAir, to predict surface-level PM_2.5 concentration in Shanghai megacity and link with MEIC emission inventory creatively to decipher urban traffic impacts on air quality. Our model exhibits high-fidelity in reproducing pollutant concentrations and reduces the MAE from 25.355 µg/m³ to 12.283 µg/m³ compared with other models. And identifies the ranking of major factors, local meteorological conditions have become a nonnegligible factor. Layer-wise relevance propagation (LRP) is used here to enhance the interpretability of the model and we visualize and analyze the reasons for the different correlation between traffic density and PM_2.5 concentration in various regions of Shanghai. Meanwhile, As the strict and effective industrial emission reduction measurements implementing in China, the contribution of urban traffic to PM_2.5 formation calculated by combining MEIC emission inventory and LRP is gradually increasing from 18.03% in 2011 to 24.37% in 2017 in Shanghai, and the impact of traffic emissions would be ever-prominent in 2030 according to our prediction. We also infer that the promotion of vehicular electrification would achieve further alleviation of PM_2.5 about 8.45% by 2030 gradually. These insights are of great significance to provide the decision-making basis for accurate and high-efficient traffic management and urban pollution control, and eventually benefit people's lives and high-quality sustainable developments of cities.     

电动汽车用电机及其控制器振动试验方法的探讨

振动试验是汽车产品设计验证和质量检验重要试验方法。本文主要从试验标准、试验条件、振动试验中主要参数的计算推导及应用、试验工装的设计、试验中应注意的问题等方面对电动汽车电机及其控制器的振动试验进行介绍。     

The Dismantling of End-of-Life Vehicles in Estonia Before Putting into Effect the Directive 2000/53/EC (3 pp)

Background, Aims and Scope When joining the European Union on 1st May 2004, Estonia had to conform its legislation to the European Union legislation. In relation with that, also the treatment requirements on end-of-life vehicles proceeding from Directive 2000/53/EC of the European Parliament and of the Council of 18 September 2000 were established in Estonia for the first time. Since this area was not regulated with law beforehand, there was not any information available about it. The aim of the current survey was to ascertain the condition of scrap yards in mid 2004. In addition to that, also to identify the number of scrap yards operating in Estonia, to classify these by the number of dismantled vehicles and the potential environmental hazard, and to map the locations of car dismantling companies and evaluate their compliance with the valid requirements. Methods The companies that have been registered in the Commercial Registry under the activity code 503090-end-of-life vehicle dismantling were visited and visually reviewed. During the visits, the compliance of scrap yards with the existing requirements was evaluated and it was also attempted to identify how environmentally sound the dismantling technology of every scrap yard owner is. Results and Discussion Altogether, 63 scrap yards operated in Estonia by mid 2004. Twelve of them dismantled more than 100 vehicles, 13 of them 51-99 vehicles and 38 up to 50 vehicles a year. The total annual market capacity on dismantling of vehicles in Estonia is considered to be approx. 10,000 units. There are very few companies dealing only with car dismantling as the main business. Most scrap-yard owners also offer side services, e.g. haulage, car repair and maintenance. The dismantlers are interested in the selling of second-hand spare parts and scrap metal. Only one company out of 63 complied with all the requirements enacted by the relevant decision of the Estonian Minister of Environment. The rest of the scrap yards did not meet the requirements on the site on storage and treatment nor did they have the hazardous waste handling licence or the waste permit. Of the requirements established for the site for storage of end-of-life vehicles, 97% of the scrap yards were surrounded with a fence, 67% had a 24-hour guard, 45% had covered the areas with waterproof cover, but only 3% had an oil trap. Sites for treatment were in a somewhat better condition, these were mostly situated inside the buildings, where floors were covered with waterproof covers. Most of the dismantlers collected the waste oil and waste fluids into separate vessels, but there were a number of dismantlers who did not know of existence of polychlorinated biphenyls (PCB) in car air conditioning systems and the availability of mercury in sensors belonging in passenger safety systems. Proceeding from the general condition of the scrap yard, the rest of 62 scarp yards were distributed between two empirical parameters - 'rather environmentally hazardous' or 'rather not environmentally hazardous'. As a matter of fact, 17% of scrap yards turned out 'rather environmentally hazardous'. Conclusion Out of the scrap yards operating in Estonia, only one is compliant with the requirements set up by Directive 2000/53/EC. Another 62 appeared during the review to be sites of potential environmental pollution. In order to comply with environmental requirements and get the hazardous waste treatment license, the scrap yard owners have to invest into state-of-the-art dismantling and environment protection equipment. The main obstacle to reach the environmentally sound scrap-yard is the high investment cost and the black market for spare parts. Recommendation and Outlook As the correction of the market in end-of-life vehicle treatment started after the adoption of Directive 2000/53/EC, the environmental authorities have to look after the ongoing correction. It is because there is still a demand for cheap spare parts and it makes it attractive to dismantle the vehicles out of scrap-yards by licensees.     

电驱动道路车辆动力锂离子电池系统气候环境试验和要求

本文是电驱动道路车辆动力锂离子电池的试验和要求标题下的气候环境部分,结合国标转化过程和实验室能力验证经历,将气候试验方法和要求作描述和解释,供实验室和相关产品的供需双方参考.     

驾驶员接管自动驾驶车辆的眼动特性和行为分析

为探究接管自动驾驶车辆期间驾驶员的视觉特性,分析眼动与接管反应操控行为的关系,开展驾驶模拟试验收集驾驶行为及眼动数据。运用统计学方法,分析驾驶员感知不同接管场景的视觉特性,探究接管请求(TOR)前后眼动指标的变化规律;并基于视觉分配和瞳孔变化特性分析驾驶行为,揭示眼动特性与接管反应及驾驶操纵策略的内在联系。结果表明:TOR前,相较于静态场景,驾驶员感知动态场景诱发元素扫视更频繁且平均注视时间更短;此时驾驶员的视觉分配特性与其接管反应行为存在显著相关性。TOR后,驾驶员的注视时间增加,眨眼频率降低,瞳孔直径扩张,眼跳幅度增大;不同场景下驾驶员的瞳孔差异表明其应对动态场景时具备更好的警戒水平和更平稳的操纵策略。     

小议机动车尾气污染的控制对策

随着城市机动车保有量的不断增长,机动车尾气污染问题已经成为城市空气污染最重要的来源,控制机动车尾气污染也已经成为改善城市大气环境质量的当务之急.本文力图通过对发达国家机动车尾气控制的经验的借鉴及中国目前状况的对比分析,为降低中国机动车尾气污染排放提供些思考和建议.     

关于我国报废汽车市场发展趋势的初步研究

随着汽车保有量的快速上升,我国报废汽车市场规模正在进入快速增长区间。根据发达国家的经验,报废汽车拆解与回收利用是循环经济产业的重要支柱。未来我国报废汽车市场规模的增长以及相关资源回收利用市场的发展,将会产生许多新的市场机会,也会对我国循环经济产业发展产生较大影响。     

Combining Coordination of Motion Actuators with Driver Steering Interaction

Objective: A new method is suggested for coordination of vehicle motion actuators; where driver feedback and capabilities become natural elements in the prioritization.

Methods: The method is using a weighted least squares control allocation formulation, where driver characteristics can be added as virtual force constraints. The approach is in particular suitable for heavy commercial vehicles that in general are over actuated. The method is applied, in a specific use case, by running a simulation of a truck applying automatic braking on a split friction surface. Here the required driver steering angle, to maintain the intended direction, is limited by a constant threshold. This constant is automatically accounted for when balancing actuator usage in the method.

Results: Simulation results show that the actual required driver steering angle can be expected to match the set constant well. Furthermore, the stopping distance is very much affected by this set capability of the driver to handle the lateral disturbance, as expected.

Conclusion: In general the capability of the driver to handle disturbances should be estimated in real-time, considering driver mental state. By using the method it will then be possible to estimate e.g. stopping distance implied from this. The setup has the potential of even shortening the stopping distance, when the driver is estimated as active, this compared to currently available systems. The approach is feasible for real-time applications and requires only measurable vehicle quantities for parameterization. Examples of other suitable applications in scope of the method would be electronic stability control, lateral stability control at launch and optimal cornering arbitration.     

Heavy duty vehicles: Impact on the environment and the path to green operation

The increase in the number of heavy duty vehicles (HDV) is inherently accompanied by increase in congestion, pollutant emissions and energy use as well as infrastructure overuse, all of which have broad societal implications. In addition to affecting the environment, contributing markedly to global warming, significant implications for the health of many residents living along traffic corridors as well as increases in the cost of infrastructure maintenance are logical consequences. In this interdisciplinary work a holistic approach is presented for the assessment of the combined effects of HDV employing pollutant emissions, noise and dynamic load of vehicles as criteria. Results show that vehicles that are environmentally friendly due to their pollutant emissions are not necessarily environmentally friendly when their noise emissions are considered. Each relevant parameter has to be assessed individually. Using a proposed model, the parameters are combined to obtain a holistic impression of the vehicles’ total environmental footprint. This information can be used by policy makers to introduce a bonus/malus system that would encourage vehicles with a total low environmental footprint using the “polluter/user pays” principle.     

基于无人机平台的甲烷监测技术及其在油气行业的应用

对甲烷排放的精准监测是油气行业实现温室气体减排与管控的基础和前提。无人机具有灵活、可操作性强、覆盖范围广、运行成本低等特点,以无人机为飞行平台的甲烷监测技术在油气行业区域甲烷排放监测领域具有巨大的应用潜力。详细阐述了基于无人机平台的甲烷监测技术的优势,梳理了不同的无人机类型,并根据其飞行性能及载荷能力进行了比对,归纳了无人机有效载荷类型、特点及应用场景,总结了国内外无人机甲烷监测技术在油气行业的应用,旨在为基于无人机平台的甲烷监测技术在我国油气行业的应用提供理论和技术参考。