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从隧道日常管理与运营维护的实际情况出发,本着"安全、可靠、经济、环保"的原则进行供电方案设计。结合某工程的负荷分布情况等,提出了横洞变式集中供电与地埋变式分散供电两种方案,经分析研究推荐采用横洞变式集中供电方案。 相似文献
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The universal composability framework is a new approach for designing and analyzing the security of cryptographic protocols. In this framework, the security of protocols is maintained under a general protocol composition operation. In the paper, we propose the universal composability framework for the analysis of proxy threshold signature and present a universally composable secure proxy threshold signature scheme which is the first one in this area. The proposed scheme is suitable for the mobile agents, which should migrate across different environment through network. Furthermore, we give the concrete analysis of the reduction to prove the security of the proposed scheme. 相似文献
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随着实时数据库应用的日益广泛,实时数据采集系统能否正常运行直接关系到实时数椐的应用效果.实时数据采集接口平稳率概念的提出,主要为系统运维人员提供了一种分析判断系统运行中故障高发环节和原因的方法,以此制定相应整改措施和事故预案,避免同类故障频繁发生. 相似文献
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Introduction of electric vehicles (EVs) or plug-in electric vehicles (PEVs) in the road transportation can significantly reduce the carbon emission. Hence, the demand of EVs is likely to increase in the near future. Large penetration of EVs will also ultimately result into high loads on the existing power grids. The controlled charging of EVs can have a significant impact on the power grid load, voltage, frequency, and power losses. In this paper, we have provided a comprehensive review of various energy optimization approaches used for EVs charging. Energy optimization approaches used for EVs not only enhance the battery life but also contribute in regulating the voltage and frequency. During EVs charging, various objective functions such as supporting the renewable energy sources, minimization of the peak load, energy cost, and maximization of the aggregator profit have also been studied from optimization perspectives. The controlled and an optimized EVs charging enhances the performance of EVs batteries and conserves the energy in the system by minimizing the load and power losses. The different EVs charging approaches such as centralized and distributed suited for different objective functions have also been studied and compared with respect to various optimization approaches. 相似文献
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Foresee traffic conditions and demand is a major issue nowadays that is very often approached using simulation tools. The aim of this work is to propose an innovative strategy to tackle such problem, relying on the presentation and analysis of a behavioural dynamic traffic assignment.The proposal relies on the assumption that travellers take routing policies rather than paths, leading us to introduce the possibility for each simulated agent to apply, in real time, a strategy allowing him to possibly re-route his path depending on the perceived local traffic conditions, jam and/or time already spent in his journey.The re-routing process allows the agents to directly react to any change in the road network. For the sake of simplicity, the agents’ strategy is modelled with a simple neural network whose parameters are determined during a preliminary training stage. The inputs of such neural network read the local information about the route network and the output gives the action to undertake: stay on the same path or modify it. As the agents use only local information, the overall network topology does not really matter, thus the strategy is able to cope with large and not previously explored networks.Numerical experiments are performed on various scenarios containing different proportions of trained strategic agents, agents with random strategies and non strategic agents, to test the robustness and adaptability to new environments and varying network conditions. The methodology is also compared against existing approaches and real world data. The outcome of the experiments suggest that this work-in-progress already produces encouraging results in terms of accuracy and computational efficiency. This indicates that the proposed approach has the potential to provide better tools to investigate and forecast drivers’ choice behaviours. Eventually these tools can improve the delivery and efficiency of traffic information to the drivers. 相似文献
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本文针对ELAN嵌入式网络微机控制系统,分析了ELAN网络系统的通信效率,提出了代码下装的方法。 相似文献
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基于分布式Q学习的区域交通协调控制的研究 总被引:2,自引:1,他引:2
介绍了强化学习和分布式Q学习的基本思想,并将分布式Q学习应用到区域交通协调控制中,通过对其进行研究和分析,提出一种适合于区域交通协调控制的奖惩函数和权值函数.在微观交通仿真软件Paramics上对控制算法进行仿真实验,实验结果说明基于分布式Q学习的区域交通协调控制算法的效果优于传统的定时控制,从而也验证了奖惩函数以及权值函数的有效性. 相似文献