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21.
Electric vehicles (EV) use an eco-friendly technology that limits the greenhouse gas emissions of the transport sector, but the limited battery capacity and the density of the battery are the major barriers to the widespread adoption of EV. To mitigate this, a good method seems to be the innovative wireless charging technology called ‘On-Line EV (OLEV)’, which is a contactless electric power transfer technology. This EV technology has the potential to charge the vehicle’s battery dynamically while the vehicle is in motion. This system helps to reduce not only the size of the battery but also its cost, and it also contributes to extending the driving range before the EV has to stop. The high cost of this technology requires an optimal location of the infrastructure along the route. For this reason, the objective of this paper is to study the problem of the location of the wireless charging infrastructure in a transport network composed of multiple routes between the origin and the destination. To find a strategic solution to this problem, we first and foremost propose a nonlinear integer programming solution to reach a compromise between the cost of the battery, which is related to its capacity, and the cost of installing the power transmitters, while maintaining the quality of the vehicle’s routing. Second, we adapt the multi-objective particle swarm optimization (MPSO) approach to our problem, as the particles were robust in solving nonlinear optimization problems. Since we have a multi-objective problem with two binary variables, we combine the binary and discrete versions of the particle swarm optimization approach with the multi-objective one. The port of Le Havre is presented as a case study to illustrate the proposed methodology. The results are analyzed and discussed in order to point out the efficiency of our resolution method.  相似文献   
22.
本文为了解决物联网所连接对象的多样性带来的标识体系存在不兼容、相互矛盾的问题,基于车联网RFID汽车电子标识的使用特点,创造性地提出将OID编码和汽车电子标识编码相结合的方案。首先简单介绍了基于发证机构及时间和基于汽车VIN码的两种OID编码规则;然后提出了OID编码在汽车电子标识芯片中的规划,主要是内存分配方案;最后介绍了相应区域的读写操作的具体方法。  相似文献   
23.
随着国家发展西部地区的力度不断加大,贵州省作为西部地区省份也乘着这股力度不断在各方面完善自己,G市作为贵州省的主要城市之一近几年在经济、政治等方面都有显著的提高。物流的发展在一定程度上可以带动一个地区产业的发展,物流的构架在一定程度上可以反映出一个地区产业的构架。通过对G市物流运营现状的分析,发现G市的产业结构的特性,然后,通过分析建立符合G市物流发展的预测模型,最后结合模型和分析对G市物流发展提出合理化建议。  相似文献   
24.
This paper discusses the situation of China's air cargo sector facing the COVID-19 pandemic. Based on the expectation that it can go out of recession more easily than China's air passenger sector, this paper analyzes four aspects that are favorable and unfavorable for its further development: (1) strengths (China's sustainable economic basis and proliferating cargo suppliers), (2) weaknesses (insufficient cargo capacity and less business internationalization), (3) opportunities (top authority support, rising e-commerce demand, and new technological momentum), and (4) challenges (uncertain trade environment and increasing profitability pressure). Then this paper suggests strategies for China's air cargo suppliers to adapt to the pandemic.  相似文献   
25.
文中探讨如何运用SWOT战略分析方法确定乌海地区铁路运输业目前面临的重要外部机会和威胁,以及内部存在的主要优势和劣势,并运用SWOT定量分析模型,对乌海铁路运输业发展做出科学评估,在此基础上明确乌海铁路货运发展战略定位,研究并提出相应的发展策略,从而充分发挥该市的自身优势。  相似文献   
26.
周翠兰 《价值工程》2014,(11):324-325
本文介绍了汽车尾气对人类健康和生态环境的危害,及其生成机理和影响因素并简述汽车尾气治理与发展。  相似文献   
27.
李东明 《价值工程》2015,(15):189-190
本文依据A320货舱门工作原理,结合航线的实际工作经验,总结分析了货舱门无法正常开关的故障原因。从液压油路,电路图两个方面分析了货舱门的操作原理,目的是快速找出最可能故障件,减少航班延误,保障航班安全。  相似文献   
28.
In a bid to reduce greenhouse gas emissions, several countries worldwide are implementing policies to promote electric vehicles (EVs). However, contrary to expectations, the diffusion speed of EVs has been rather slow in South Korea. This study analyzes consumer preferences for the technological and environmental attributes of EVs and derives policy and environmental implications to promote market diffusion of EVs in South Korea. We conduct a choice‐based conjoint survey of 1,008 consumers in South Korea and estimate the consumer utility function using a mixed logit model considering consumer heterogeneity. Based on the consumer utility function, we analyze consumers' willingness‐to‐pay (WTP) for EV attributes such as driving range, charging method, charging time, autonomous driving function, carbon dioxide (CO2) reduction rate, and purchase price. The results indicate that the current low acceptance of EVs is due to their relatively high price and lack of a battery charging technology that satisfies consumers' expectations of the charging method and time. One interesting finding is that Korean consumers have a relatively higher WTP for the CO2 reduction rate of EVs than consumers in other countries; however, they do not consider CO2 reduction over other technological attributes when choosing EVs. This implies that the rate of CO2 reduction of EVs is not an important factor for South Korean consumers when buying EVs. We also calculate the effect of CO2 reduction with the market penetration of EVs and find that CO2 reduction through the diffusion of EVs depends on the country's electricity generation mix.  相似文献   
29.
As in other emerging nations, in Brazil, the motor vehicle industry is considered to be strategically important for economic development because of its backward and forward linkages and possibilities for export-led growth. This study analyses prospects for the industry by estimating an industry-level cost function that includes output of both vehicles and component parts with capital, labour and intermediate goods as inputs. The cost elasticity of output (an indicator of scale properties) and the elasticity relationships among inputs are explored. One unexpected outcome of the work that appears to be robust is that during early years of the study period, the industry had constant returns or even diseconomies of scale. However, during later years, when output was greater, there were economies of scale. This finding is likely the result of some combination of the entry of new firms, the development of new models or technological change. The study concludes that if firm output can be increased, economies of scale can be expected to strengthen the position of the Brazilian industry in the international marketplace.  相似文献   
30.
传统的无线定位方法直接应用于车辆自组织网络(VANET)时,会被窃听方利用定位信息,从而导致严重的安全隐患。为此,提出基于Bancroft方法的双群组合定位算法,用于保障车辆自组织网络中车辆定位的安全性和准确性。算法利用两个群组的智能车辆节点分别进行定位,利用两组解分别反求伪距值,如果所获得的伪距值与经过节点钟差修正后的原始伪距值基本一致,则认为这一组解为最终的定位结果,从而保证了定位的正确性。同时,双群定位的信息分散性保证了系统整体的安全性。理论分析及算法仿真表明,双群联合定位算法可使窃听方的误码率稳定在较高水平。  相似文献   
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