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101.
随着国家对环境保护和能源节约的重视以及新能源政策的实施,电动汽车行业迎来了快速发展。充电基础设施的建设,是加快电动汽车推广的重要需要。电动汽车充电基础设施建设和运营业务发展的机会也极大,随之而来的安全管理工作要求也越来越高。本文依据充电桩建设和运营的特点,剖析其中面临的安全风险,并提出加强安全管理工作的措施,为充电桩企业安全管理运营提供参考和借鉴。 相似文献
102.
阐述了基于云平台的城市轨道交通能源管理系统架构和建设方式.该系统利用云计算的高效和弹性来部署建设,采用线网-车站二层管理模式,降低了线网和线路服务器等的硬件部署成本和维护成本.通过将能源管理系统内部使用的业务应用转换为基于云平台的能源管理应用软件,能源管理系统可获取云平台提供的共享数据,并将经过业务处理后的数据存储到云... 相似文献
103.
许爱琼 《郑州铁路职业技术学院学报》2021,(1)
学生评教是提高高校教育教学管理质量的有效监督手段,通过学生评教促进教师教学、科研能力的全面提升。从立德树人、教学相长、尊师重教、回归教学本真四个方面发挥学生评教功能。 相似文献
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Railway rapid transit systems are key stones for the sustainability of mass transit in developed countries. The overwhelming majority of these railway systems are direct-current (DC) electrified and several energy-saving techniques have been proposed in the literature for these systems. The use of regenerative-braking in trains is generally recognised as the main tool to improve the efficiency of DC-electrified mass transit railway systems but the energy recovered in braking cannot always be handled efficiently, above all in low traffic-density situations. Several emerging technologies as energy storage systems or reversible traction substations have the potential for making it possible to efficiently use train-braking. However, a systematic evaluation of their effect is missing in the literature.In this paper, a deep, rigorous and comprehensive study on the factors which affect energy issues in a DC-electrified mass transit railway system is carried out. This study clarifies what the actual potential is for energy saving in each situation. Then, a methodology to asses several energy-saving techniques to improve energy efficiency in DC-electrified mass transit systems is presented, constituting the main contribution of this paper. This methodology has been conceived to help operators in assessing the effect of railway-infrastructure emerging technologies in transit systems, so making it possible to shape planning, capacity, etc. It is stepped out in three basic movements. First of all, a traffic-density scan analysis is conducted in order to clarify the effect of the headway on system behaviour. Secondly, several traffic-density scenarios are simulated for a set of infrastructure-expanded cases. Finally, annual energy saving is evaluated by applying a realistic operation timetable. This methodology has been applied to a case study in Madrid Metro (Spain) to illustrate the steps of its application and the effect of several energy-saving techniques on this specific system. Results confirm that regenerative braking generally leads to an important increase of system energy efficiency – especially at high traffic-density scenarios. It has also been proved that infrastructure improvements can also contribute to energy savings and their contributions are more significant at low traffic densities. Annual energy results have been obtained, which may lead to investment decisions by carrying out an appropriate economic assessment based on cost analysis.The main results of the study presented here are likely to apply to other electric traction systems, at least qualitatively. 相似文献
107.
Sibok Lee Raymond A. Krammes John Yen 《Transportation Research Part C: Emerging Technologies》1998,6(5-6)
This paper documents a fuzzy-logic-based incident detection algorithm for signalized urban diamond interchanges. The model is capable of detecting lane-blocking incidents whose effects are manifested by patterns of deterioration in traffic conditions that require adjustments in signal control strategies. As a component of a real-time traffic adaptive control system for signalized diamond interchanges, the algorithm feeds an incident report (i.e., the time, location, and severity of the incident) to the system's optimization manager, which uses that information to determine the appropriate signal control strategy.The performance of the model was studied using a simulation of an actual diamond interchange. The simulation study evaluated the model's performance in terms of detection rate, false alarm rate, and mean time to detect. The model's performance was encouraging, and the fuzzy-logic-based approach is considered promising. 相似文献
108.
船舶压载水不仅危害海洋环境还会对人类健康、当地经济造成影响,《国际船舶压载水和沉积物控制和管理公约》实施即说明了国际社会对此的重视。压载水处理系统的使用,有效地减小了压载水对环境的危害。然而在实际应用中,仍需要通过提高和改进压载水监控技术,使处理后的压载水进一步符合公约标准。本研究根据我国压载水监控现状,提出完善压载水监督管理的措施,促进我国环境、经济和资源的可持续发展。 相似文献
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《铁路技术管理规程》是我国铁路的基本规章,研究不同版本的演变特征对其管理及不断修订完善具有重要意义。通过对铁路列车提速以来近三版《铁路技术管理规程》修订背景回顾与发展历程分析,基于文本相似度算法,构建了不同版本间的条款关联关系并量化分析了相邻版本及各个章节条款关联强度。运用政策文献计量法,逐版逐条研究其修订类型并从版本与章节两个维度分别量化分析了条款修订类型分布特征。在此基础上,总结提出了《铁路技术管理规程》演变发展特征与趋势。该研究对《铁路技术管理规程》的科学管理及今后动态修订完善具有重要支撑作用。 相似文献