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改善驾驶行为、推广生态驾驶是未来降低机动车辆燃油消耗和污染排放的重要潜在方式.分析由车辆远程在线监控技术(OBD)获取的199辆大型货车在观测的4 d内的位置、速度、油耗等微观运行状态的逐秒数据,提出判定急加速、过急加速、急减速、过急减速和超长怠速等5种不良驾驶行为的统计方法,并建立面板数据固定效应回归模型分析5种不良驾驶行为对大型货车油耗的影响,进而定量评估改善不良驾驶行为的节油潜力.研究结果表明,超长怠速和过急减速行为会显著增加大型货车的油耗,减少超长怠速时间和过急减速行为的节油潜力分别可达2.6%和3.8%. 相似文献
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Electric travelling appears to dominate the transport sector in the near future due to the needed transition from internal combustion vehicles (ICV) towards Electric Vehicles (EV) to tackle urban pollution. Given this trend, investigation of the EV drivers’ travel behaviour is of great importance to stakeholders including planners and policymakers, for example in order to locate charging stations. This research explores the Battery Electric Vehicle (BEV) drivers route choice and charging preferences through a Stated Preference (SP) survey. Collecting data from 505 EV drivers in the Netherlands, we report the results of estimating a Mixed Logit (ML) model for those choices. Respondents were requested to choose a route among six alternatives: freeways, arterial ways, and local streets with and without fast charging. Our findings suggest that the classic route attributes (travel time and travel cost), vehicle-related variables (state-of-charge at the origin and destination) and charging characteristics (availability of a slow charging point at the destination, fast charging duration, waiting time in the queue of a fast-charging station) can influence the BEV drivers route choice and charging behaviour significantly. When the state-of-charge (SOC) at the origin is high and a slow charger at the destination is available, routes without fast charging are likely to be preferred. Moreover, local streets (associated with slow speeds and less energy consumption) could be preferred if the SOC at the destination is expected to be low while arterial ways might be selected when a driver must recharge his/her car during the trip via fast charging. 相似文献
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在核动力破冰船设计中,通常为了适应推进系统频繁大幅度负荷变化,核蒸汽发生装置必须工作在很宽的功率范围上,且具有灵活快速的负荷跟踪特性,导致核动力装置的低效率与核蒸汽发生装置的高功率密度。本文提出一种电力推进系统设计方案:利用储能单元具有的"削峰填谷"能力,承担电力推进负载的瞬时或短时功率变化,使系统负荷维持在一个平稳的波动范围内,以改善电力推进系统负荷扰动对汽轮发电机组的不良影响,使汽轮发电机组维持在一个较为恒定的功率输出水平,来降低核蒸汽发生装置阶跃功率调节的频率,使其能尽可能地进行线性功率调节。 相似文献
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Real-time energy trading services for privately owned non-commercial electric vehicles are characterized by an e-vehicle provider, by a provider of energy trading skills and technology, and by the fact that the latter manages (dis-)charging of the e-vehicle of the former with real-time energy prices. We conduct a simulation study to present a comprehensive assessment of the financial value of such services. Such an assessment is required in order to provide policymakers with guidance on if and how real-time trading services can serve as a tool to incentivize e-vehicle ownership. We propose a fully reproducible simulation model of the value creation process of real-time trading services, and use the model to assess services with a range of e-vehicle provider characteristics as well as with a range of technology setups. Our empirical results show that all considered real-time trading services are able to create significant energy cost savings, and that overall cost savings strongly depend on technology characteristics, surcharge rate, as well as on the e-vehicle provider's commute, household size, and office hours. We show that services including solar energy generation have the largest economic potential but do not necessarily maximize renewable energy deployment with residential households. We conclude with recommendations for policymakers on how to tap the full economic potential of real-time trading services for stimulating the adoption of e-vehicles. 相似文献
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