LugDown法设备性能的改进与完善方法

介绍了用于柴油车排气检测的加载减速工况（LugDown）法设备的构成与测量原理，分析了 LugDown 法设备在加载、功率扫描控制、排气测量控制等方面存在的问题。对照国标要求，结合 LugDown法设备的工作特点，探讨了在功率扫描性能、寄生滑行性能、排气测量过程控制、测试档位选择与扫描起始速度控制等方面的改进与完善方法。     

Sustainable design for automotive products: Dismantling and recycling of end-of-life vehicles

The growth in automotive production has increased the number of end-of-life vehicles (ELVs) annually. The traditional approach ELV processing involves dismantling, shredding, and landfill disposal. The “3R” (i.e., reduce, reuse, and recycle) principle has been increasingly employed in processing ELVs, particularly ELV parts, to promote sustainable development. The first step in processing ELVs is dismantling. However, certain parts of the vehicle are difficult to disassemble and use in practice. The extended producer responsibility policy requires carmakers to contribute in the processing of scrap cars either for their own developmental needs or for social responsibility. The design for dismantling approach can be an effective solution to the existing difficulties in dismantling ELVs. This approach can also provide guidelines in the design of automotive products. This paper illustrates the difficulty of handling polymers in dashboards. The physical properties of polymers prevent easy separation and recycling by using mechanical methods. Thus, dealers have to rely on chemical methods such as pyrolysis. Therefore, car designers should use a single material to benefit dealers. The use of materials for effective end-of-life processing without sacrificing the original performance requirements of the vehicle should be explored.     

Knowledge,experience and the circus: academic perspectives on the processes of communicating the environmental and health impacts of electric vehicles

The translation of research findings into public realms has important implications for alternative technologies, such as electric vehicles (EVs). Much existing science communication research focuses on the agency of different publics in processes of scientific knowledge uptake. This study uses research related to the environmental and health impacts of EVs as a case study to explore how the individual agency of academic researchers can influence communication. Challenges to communication and opportunities to enhance the agency of researchers to engage in public dialogue are identified, with a focus on academics at different stages of their careers. This paper proposes a new way of understanding how these individualised nuances impact the communication of a particular researcher’s findings. These nuances are built through the researcher’s agency; a construct of their past experiences, professional and personal relationships with other actors and previous practices of communicating to publics. Communication models have previously concentrated on the heterogeneity of other actors and publics with the huge assumption that academics work consistently, homogenously, in a neutral way to the benefit of society. EVs were chosen as an appropriate case study as they are a contemporary technology that relies on the communication of knowledge and the public understanding of this knowledge to cater for future needs. The responses elicited from the interviews highlight the individual geographies of knowledge. Hence, a reflexive understanding of their role as an individual can provide valuable insights into how a researcher may distribute knowledges more effectively in their geographies to publics     

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.     

Research on the recycling industry development model for typical exterior plastic components of end-of-life passenger vehicle based on the SWOT method

In-depth studies on the recycling of typical automotive exterior plastic parts are significant and beneficial for environmental protection, energy conservation, and sustainable development of China. In the current study, several methods were used to analyze the recycling industry model for typical exterior parts of passenger vehicles in China. The strengths, weaknesses, opportunities, and challenges of the current recycling industry for typical exterior parts of passenger vehicles were analyzed comprehensively based on the SWOT method. The internal factor evaluation matrix and external factor evaluation matrix were used to evaluate the internal and external factors of the recycling industry. The recycling industry was found to respond well to all the factors and it was found to face good developing opportunities. Then, the cross-link strategies analysis for the typical exterior parts of the passenger car industry of China was conducted based on the SWOT analysis strategies and established SWOT matrix. Finally, based on the aforementioned research, the recycling industry model led by automobile manufacturers was promoted.     

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。     

Stability and safety evaluation of mixed traffic flow with connected automated vehicles on expressways

Introduction: Connected automated vehicles (CAVs) technology has deeply integrated advanced technologies in various fields, providing an effective way to improve traffic safety. However, it would take time for vehicles on the road to vehicles from human-driven vehicles (HDVs) progress to CAVs. Moreover, the Cooperative Adaptive Cruise Control (CACC) vehicle would degrade into the Adaptive Cruise Control (ACC) vehicle due to communication failure. Method: First, the different car-following models are used to capture characteristics of different types of vehicles (e.g., HDVs, CACC, and ACC). Second, the stability of mixed traffic flow is analyzed under different penetration rates of CAVs. Then, multiple safety measures, such as standard deviation of vehicle speed (SD), time exposed rear-end crash risk (TER), time exposed time-to-collision (TET), and time-integrated time-to-collision (TIT) are used to evaluate the safety of mixed traffic flow on expressways. Finally, the sensitivity of traffic demand, the threshold of time-to-collision (TTC), and the parameters of car-following models are analyzed based on a numerical simulation. Results: The results show that the ACC vehicle has no significant impact on the SD of mixed traffic flows, but it leads to the deterioration of TET and TIT, making the reduction proportion of TER slower. When the penetration rate exceeds 50%, the increase of CACC vehicles reduces traffic safety risks significantly. Furthermore, the increase in traffic demand and car-following parameters worsens traffic safety on expressways. Conclusions: This paper suggests that the CACC vehicles degenerate into ACC vehicles due to communication failure, and the safety risk of mixed traffic flow increases significantly. Practical Applications: The application of CAVs can improve the stability and safety of traffic flow.     

夜间动态环境中空间距离驾驶员判识变化

为研究驾驶员在夜间地面动态环境中距离判识变化的规律,改进行车安全.选取32名驾驶员进行实际道路试验.被试在自车行进方向不同的深度距离、车速下,判识前方障碍物的绝对距离和相对距离.统计距离判识值,得出夜间距离判识值数据分布,取得距离判识特征值.回归分析判识距离与速度的关系,建立障碍物判识变化的数学模型.比较昼夜距离判识差异,分析其对夜间行车安伞的影响.结果表明:在车辆行驶深度方向,夜间距离判识值随速度增加而不断下降,两者之间呈负指数关系;在相同深度距离和速度下,夜间判识距离大于昼间;夜间行车时,需适当降低车速,确保有效的安伞距离.     

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。     

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。