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1.
Developments in battery electric vehicles (BEVs) have received more and more attentions in the last decades due to alleviating carbon emissions and energy crisis. Consequently, how to rank alternative BEVs to assist consumers make better purchasing decisions is a worthy research study. However, there are still some defects in the existing studies for ranking of BEVs: 1) the evaluation index system of BEVs is not comprehensive; 2) the determination of criteria weights cannot be well applied to the actual purchase scenarios; and 3) the psychological behavior of consumers is ignored. To address those shortcomings, this paper proposes a decision support model to assist with consumers to buy BEVs. First, a systematic evaluation criteria system of BEVs including quantitative and qualitative indicators from parameter configurations and online reviews is constructed. Then, a weight algorithm considering consumer learning is proposed to determine the criteria weights. Furthermore, a decision support process considering consumers' regret avoidance behavior is proposed. Finally, an actual BEV purchase case is given to illustrate the practicability of the decision support model. This can be seen in case studies the proposed support model can be well applied to consumers with different regret avoidance behaviours.  相似文献   
2.
[目的]在统计描述华北平原农民的机械采纳率和机械采纳方式的基础上,分析农民的机械化需求和农机手的机械服务供给行为及其内在逻辑,从理论和实证两个维度对华北平原地区农业机械技术的特殊实现形式——服务外包做出解释。[方法]运用描述性统计分析和成本收益核算等方法,利用冀豫鲁3省779个农户和45个农机手的实地调研数据分别对农业机械化发展的前提条件和实现方式做出解释。[结果]农业劳动力成本上升与农机购置成本下降,共同刺激了农民的机械技术需求,是华北平原农业机械化快速发展的前提条件;持有农业机械的农民基于理性选择而向其他农民提供农机作业服务,是推动华北平原农业机械化以服务形式实现的主要原因。[结论]相关部门应继续探索高效的农机补贴模式,刺激农民的机械技术需求;农业机械支持政策可适当向农机合作社倾斜,提高农机手的组织化程度和服务数量与质量。  相似文献   
3.
Replacing conventional vehicle taxis with electric vehicles would be an efficient measure to reduce greenhouse gas emissions. Due to the limited range and long charging times of current battery electric vehicles, it is of utmost importance to provide sufficient charging facilities. This article analyses the impact of the placement and charging power of charging stations on potential mileage and revenue of electric taxis on the example of Singapore. Therefore, we developed an agent-based electric taxi simulation model to investigate electric taxis’ driving profiles with respect to different vehicle types and charging infrastructure designs. This model is also capable of simulating conventional taxi driving profiles. The validation of these simulation results with real taxi data showed that the model is reproducing taxi driving profiles with high accuracy in great detail. We found out that electric taxis could reach the same mileage and revenue as conventional taxis if charging with a power of 160?kW is possible. Furthermore, we discovered that waiting times for available charging stations have a stronger effect on revenue than the length of detours to reach charging stations. Based on these findings, we concluded that it is more important to reduce waiting times by placing sufficient numbers of charging stations at each location before expanding the charging network by installing small numbers of charging stations at many locations.  相似文献   
4.
随着当前科学技术的发展,在烟草检验机械设备研发的过程中,也在向着高速度以及智能化的方向进行研发。对于烟草卷烟机械设备行业来讲,在发展的过程中,针对维修工的要求也在随之提升。所以为了能够保证烟草卷烟机的设备维修工作的相关需求得到满足,需要就当前烟草卷烟机械设备维修工作进行深入探讨。  相似文献   
5.
Improving fuel economy and lowering emissions are key societal goals. Standard driving cycles, pre-designed by the US Environmental Protection Agency (EPA), have long been used to estimate vehicle fuel economy in laboratory-controlled conditions. They have also been used to test and tune different energy management strategies for hybrid electric vehicles (HEVs). This paper aims to estimate fuel consumption for a conventional vehicle and a HEV using personalized driving cycles extracted from real-world data to study the effects of different driving styles and vehicle types on fuel consumption when compared to the estimates based on standard driving cycles. To do this, we extracted driving cycles for conventional vehicles and HEVs from a large-scale U.S. survey that contains real-world GPS-based driving records. Next, the driving cycles were assigned to one of three categories: volatile, normal, or calm. Then, the driving cycles were used along with a driver-vehicle simulation that captures driver decisions (vehicle speed during a trip), powertrain, and vehicle dynamics to estimate fuel consumption for conventional vehicles and HEVs with power-split powertrain. To further optimize fuel consumption for HEVs, the Equivalent Consumption Minimization Strategy (ECMS) is applied. The results show that depending on the driving style and the driving scenario, conventional vehicle fuel consumption can vary widely compared with standard EPA driving cycles. Specifically, conventional vehicle fuel consumption was 13% lower in calm urban driving, but almost 34% higher for volatile highway driving compared with standard EPA driving cycles. Interestingly, when a driving cycle is predicted based on the application of case-based reasoning and used to tune the power distribution in a hybrid electric vehicle, its fuel consumption can be reduced by up to 12% in urban driving. Implications and limitations of the findings are discussed.  相似文献   
6.
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   
7.
新能源汽车是未来汽车产业转型发展的重要方向。我国新能源汽车前期发展取得了突出的成绩,产销量位居世界首位。但目前产业发展正面临新形势,未来一段时期内将由“政策驱动”转向“政策+市场双驱动”。到2021年购置补贴完全退出后的后补贴时代,如何保障新能源汽车产业的健康、可持续发展,值得人们共同思考,开发什么类型的产品才能更好地满足消费者的需求,值得行业企业考虑。  相似文献   
8.
Long considered a ‘Ricardian socialist’, Thomas Hodgskin is rarely read as the perceptive observer of the Industrial Revolution that he was. His most famous pamphlet, Labour Defended Against the Claims of Capital, has been interpreted as anticipating some central tenets of Marxism. If we abandon this well‐established interpretation, however, we can better appreciate Hodgskin's acute reading of the process of industrialisation unfolding before his eyes. Unlike most socialists, Hodgskin had no sympathy for machine breakers and actually understood the importance of the entrepreneurial function. Moreover, he thought mechanisation and improvement in the tools available for workers would not dispossess them but, on the contrary, would raise their living standards. Hodgskin's ‘optimism’ shows that in the 1820s someone who was deeply concerned with the future of the working classes could nonetheless develop a reasoned sympathy for industrialisation — rather than merely oppose technological innovation and long for a mythical past.  相似文献   
9.
市场经济的高速发展为我国各领域创新改革带来重大机遇,特别是对于生产型企业而言更是如此,为了提高经济效益,在激烈竞争中脱颖而出,势必将更多关注度放到内部的设备管理中。鉴于此,本文将着重分析现代生产型企业机械设备管理情况,了解机械设备管理中存在的问题,提出具体优化策略,旨在为更好的进行机械设备管理,促进企业的持续发展。  相似文献   
10.
为了提高双离合变速器在车辆上的换挡品质,提升电气化换挡执行机构的工作效率,给出执行机构性能与换挡品质评价准则;通过两种不同双离合变速器电控电动执行机构的工作原理与性能分析,基于MATLAB数值仿真方法优化出最高效率进行试验.基于车辆6个维度的换挡工况对二者所搭载的变速器分别进行试验与CAN线数据采集,对比研究两种机构优缺点,通过雷达图的方式进行优劣说明.结果表明,两种执行机构传动效率可达70%且换挡品质相当.可见Tip in tip out工况对二者要求最为严格.  相似文献   
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