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FACOR：Flexible Access Control with Outsourceable Revocation in Mobile Clouds

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China communications 2016年第4期13卷 136-150页

作者： ZHOU Shungan DU Ruiying CHEN Jing SHEN Jian DENG Hua ZHANG Huanguo The Key Laboratory of Aerospace Information Security and Trusted Computing Ministry of Education Computer School of Wuhan University Wuhan 430072 China State Grid Information and communication company of Hunan Electric power Corp Changsha 410000 China

Access control is a key mechanism to secure outsourced data in mobile clouds. Some existing solutions are proposed to enforce flexible access control on outsourced data or reduce the computations performed by mobile devices. However, less attention has been paid to the efficiency of revocation when there are mobile devices needed to be revoked. In this paper, we put forward a new solution, referred to as flexible access control with outsourceable revocation(FACOR) for mobile clouds. The FACOR applies the attribute-based encryption to enable flexible access control on outsourced data, and allows mobile users to outsource the time-consuming encryption and decryption computations to proxies, with only requiring attributes authorization to be fully trusted. As an advantageous feature, FACOR provides an outsourceable revocation for mobile users to reduce the complicated attribute-based revocation operations. The security analysis shows that our FACOR scheme achieves data security against collusion attacks and unauthorized accesses from revoked users. Both theoretical and experimental results confirm that our proposed scheme greatly reliefs the mobile devices from heavy encryption and decryption computations, as well as the complicated revocation of access rights in mobile clouds.

关键词： mobile cloud computing ABE outsourcing user revocation

Energy efficient downlink MIMO transmission with linear precoding

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Science China(Information Sciences) 2013年第2期56卷 90-101页

作者： XU Jie LI ShiChao QIU Ling SLIMANE Ben S. YU ChengWen Department of Electronic Engineering and Information Science University of Science and Technology of China Department of communication Systems (CoS) ICT The Royal Institute of Technology (KTH) Wireless Research Huawei Technologies Company Limited

Energy efficiency (EE) is becoming increasingly important for wireless cellular networks. This paper addresses EE optimization problems in downlink multiuser MIMO systems with linear precoding. Referring to different active transmit/receive antenna sets and transmission schemes as different modes, we propose a joint bandwidth/power optimization and mode switching scheme to maximize EE. With a specific mode, we prove that the optimal bandwidth and transmit power is either full transmit power or full bandwidth. After deriving the optimal bandwidth and transmit power, we further propose mode switching to select the mode with optimal EE. Since the optimal mode switching, i.e. exhaustive search, is too complex to implement, an alternative heuristic method is developed to decrease the complexity through reducing the search size and avoiding the EE calculation during each search. Through simulations, we demonstrate that the proposed methods can significantly improve EE and the performance is similar to the optimal exhaustive search.

关键词： energy efficiency downlink multiuser MIMO linear precoding bandwidth/power optimization mode switching low complexity

Optimal operation of electricity, natural gas and heat systems considering integrated demand responses and diversified storage devices

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Journal of Modern power Systems and Clean Energy 2018年第3期6卷 423-437页

作者： Linna NI Weijia LIU Fushuan WEN Yusheng XUE Zhaoyang DONG Yu ZHENG Rui ZHANG Research Institute of State Grid Zhejiang Electric power company School of Electrical Engineering Zhejiang University State Grid Electric power Research Institute Electric power Research Institute China Southern Power Grid

In recent years, the increasing penetration level of renewable generation and combined heat and power(CHP) technology in power systems is leading to significant changes in energy production and consumption patterns. As a result, the integrated planning and optimal operation of a multi-carrier energy(MCE) system have aroused widespread concern for reasonable utilization of multiple energy resources and efficient accommodation of renewable energy sources. In this context, an integrated demand response(IDR) scheme is designed to coordinate the operation of power to gas(P2 G) devices, heat pumps,diversified storage devices and flexible loads within an extended modeling framework of energy hubs. Subsequently, the optimal dispatch of interconnected electricity,natural gas and heat systems is implemented considering the interactions among multiple energy carriers by utilizing the bi-level optimization method. Finally, the proposed method is demonstrated with a 4-bus multi-energy systemand a larger test case comprised of a revised IEEE 118-bus power system and a 20-bus Belgian natural gas system.

关键词： Multi-carrier energy(MCE) system Diversified storage device Integrated demand response(IDR) Smart energy hub(SEH) power to gas(P2G) Heat pump

Application of fuzzy analytic hierarchy process and neural network in power transformer risk assessment

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Journal of Central South University 2012年第4期19卷 982-987页

作者：李卫国俞乾罗日成 Beijing Key Laboratory of High Voltage&Electro Magnetic Compatibility North China Electric Power University Yongzhou Electric power Bureau Hunan Electric Company College of Electrical and Information Engineering Changsha University of Science and Technology

In operation,risk arising from power transformer faults is of much uncertainty and *** timely and objectively control the risks,a transformer risk assessment method based on fuzzy analytic hierarchy process(FAHP) and artificial neural network(ANN) from the perspective of accuracy and quickness is *** analytic hierarchy process model for the transformer risk assessment is built by analysis of the risk factors affecting the transformer risk level and the weight relation of each risk factor in transformer risk calculation is analyzed by application of fuzzy consistency judgment matrix;with utilization of adaptive ability and nonlinear mapping ability of the ANN,the risk factors with large weights are used as input of neutral network,and thus intelligent quantitative assessment of transformer risk is *** simulation result shows that the proposed method increases the speed and accuracy of the risk assessment and can provide feasible decision basis for the transformer risk management and maintenance decisions.

关键词： fuzzy analytic hierarchy process risk assessment power transformer artificial neutral network

Operation-area-constrained Adaptive Primary Frequency Support Strategy for Electric Vehicle Clusters

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Journal of Modern power Systems and Clean Energy 2023年第6期11卷 1982-1994页

作者： Tianqi Liu Pengyu Wang Qiao Peng Min Zhang Tengxin Wang Jinhao Meng College of Electrical Engineering Sichuan UniversityChengdu 610065China Electric power Research Institute State Grid Shanxi Electric Power CompanyTaiyuan 030001China

Due to their fast response and strong short-term power throughput capacity, electric vehicles(EVs) are promising for providing primary frequency support to power grids. However, due to the complicated charging demands of drivers, it is challenging to efficiently utilize the regulation capacity of EV clusters for providing stable primary frequency support to the power grid. Accordingly, this paper proposes an adaptive primary frequency support strategy for EV clusters constrained by the charging-behavior-defined operation area. First, the forced charging boundary of the EV is determined according to the driver's charging behavior, and based on this, the operation area is defined. This ensures full utilization of the available frequency support capacity of the EV. An adaptive primary frequency support strategy of EV clusters is then proposed. The output power of EV is adaptively regulated according to the real-time distance from the EV operating point to the forced charging boundary. With the proposed strategy, when the EV approaches the forced charging boundary, its output power is gradually reduced to zero. Then, the rapid state-of-charge declines of EVs and sudden output power reductions in EV clusters caused by forced charging to meet the driver's charging demands can be effectively avoided. EV clusters can then provide sustainable frequency support to the power grid without violating the driver's charging demands. Simulation results validate the proposed operation-area-constrained adaptive primary frequency support strategy, which outperforms the average strategy in terms of stable output maintenance and the optimal utilization of regulation capacities of EV clusters.

关键词： Primary frequency control frequency support electric vehicle vehicle-to-grid(V2G) operation area charging behavior

Benefit allocation of electricity-gas-heat-hydrogen integrated energy system based on Shapley value

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Clean Energy 2023年第6期7卷 1381-1390页

作者： Yujiao Liu Yan Li Yiping Rong Guoliang Li Ruiqi Wang Haini Zhou Zaozhuang power Supply company of State Grid Shandong Province Electric power company Zaozhuang CityShandong 277101China State Grid Shandong Integrated Energy Services Jinan CityShandong 250021China

The integrated energy system is an important development direction for achieving energy transformation in the context of the low-carbon development era,and an integrated energy system that uses renewable energy can reduce carbon emissions and improve energy utilization *** electric power network and the natural gas network are important transmission carriers in the en-ergy field,so the coupling relationship between them has been of wide *** paper establishes an integrated energy system considering electricity,gas,heat and hydrogen loads;takes each subject in the integrated energy system as the research object;anal-yses the economic returns of each subject under different operation modes;applies the Shapley value method for benefit allocation;and quantifies the contribution value of the subject to the alliance through different influencing factors to revise the benefit allocation *** with the independent mode,the overall benefits of the integrated energy system increase in the cooperative mode and the benefits of all subjects *** to the different characteristics of different subjects in terms of environmental benefits,collaborative innovation and risk sharing,the benefit allocation is reduced for new-energy subjects and increased for power-to-gas sub-jects and combined heat and power generation units after revising the benefit allocation,to improve the matching degree between the contribution level and the benefit allocation under the premise of increased profit for each *** cooperative mode effectively enhances the economic benefits of the system as a whole and individually,and provides a useful reference for the allocation of benefits of integrated energy *** analysis shows that the revised benefit distribution under the cooperative model increases by 3.86%,4.08%and 3.13%for power-to-gas subjects,combined heat and power generation units,and new-energy units,respectively,compared with the independent function m

关键词： integrated energy system power-to-gas Shapley value benefit allocation hydrogen energy

A preventive opportunistic maintenance method for railway traction power supply system based on equipment reliability

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Railway Engineering Science 2020年第2期28卷 199-211页

作者： Sheng Lin Nan Li Ding Feng Xiaomin Guo Weiguo Pan Jun Wang Chao Yang School of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China Beijing National Railway Research&Design Institute of Signal communication Group company Beijing 100070China State Grid Neijiang Electric power Supply company Neijiang 641100China

Conventional maintenance mode for the traction power supply system(TPSS)is to perform scheduled regular maintenance activities for power supply equipment,while such maintenance mode may result in undue maintenance tasks and low efficiency due to different degradation processes of different sorts of *** address this problem,this paper introduces a preventive opportunistic maintenance(POM)method for TPSS based on equipment ***,a POM model is established by considering the equipment reliability degradation process based on Weibull ***,by considering the total power outage time in the planned operation cycle of TPSS as the optimization objective,the optimal maintenance scheme of TPSS is formulated by iterative method of maintenance *** proposed method is verified by introducing practical maintenance strategies and fault record data of the traction transformer,circuit breaker and disconnector in an actual TPSS of a railway *** show that the presented method can make full use of the existing fault data to develop a POM scheme for *** can improve maintenance efficiency and reduce power outage time,providing guidance to formulate scientific maintenance strategies for TPSS.

关键词： Electrified railway Opportunistic maintenance interval Preventive opportunistic maintenance Reliability Traction power supply system Weibull distribution

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基于炉膛火焰发射光谱的煤种识别（英文）

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2017年第2期18卷 113-123页

作者： Feng YIN Zhi-hao LUO Yuan LI Ming-xi ZHOU Hao ZHOU State Key Laboratory of Clean Energy utilization Zhejiang University Hangzhou 310027 China Electric power Research Institute of State Grid Zhejiang Electric power company Hangzhou 310014 China

目的:为解决煤种频繁变化造成的燃烧闭环优化难题,研究在燃烧器出口实时辨识锅炉入炉燃烧煤种的方法。创新点:1.通过火焰发射光谱机理研究获取可排除燃烧工况与测量采样等干扰因素的算法规则;2.提出基于煤粉火焰光谱中Na和K元素原子发... 详细信息

目的:为解决煤种频繁变化造成的燃烧闭环优化难题,研究在燃烧器出口实时辨识锅炉入炉燃烧煤种的方法。创新点:1.通过火焰发射光谱机理研究获取可排除燃烧工况与测量采样等干扰因素的算法规则;2.提出基于煤粉火焰光谱中Na和K元素原子发射光谱相对强度特征的煤种辨识方法。方法:1.通过光纤光谱仪获取锅炉各层燃烧器入口火焰光谱信号;2.利用同波长下原子光谱与连续辐射光谱的相对关系,消去火焰温度、工况与环境的影响;3.以补偿后Na和K元素原子发射光谱强度的特征比值表征不同煤种在火焰中的元素含量特征,实现煤种的在线辨识。结论:1.利用煤粉火焰光谱特征实现入炉煤种的实时辨识具有良好的工况稳定性与可复现性;2.从算法机理中消除环境影响,降低了测量系统校验的复杂性。

关键词：在线辨识火焰发射光谱碱金属谱线强度

A Storage and Transmission Joint Planning Method for Centralized Wind power Transmission

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Computers, Materials & Continua 2021年第7期68卷 1081-1097页

作者： Xiuyu Yang Qi Guo Jianzhong Gui Renyong Chai Xueyuan Liu Key Laboratory of Modern power System Simulation and Control&Renewable Energy technology(Northeast Electric power University) Jilin132012China Electrical Engineering-PHD program at the University of Idaho Idaho83843America State Grid Jiangxi power Supply company Xinyu338025China

Centralized delivery has become the main operation mode under the scaled development of wind *** channels are usually the guarantee of out-delivered wind power for large-scale wind *** configuration of transmission capacity,which has the features of low utilization and poor economy,is hardly matching correctly due to the volatility and low energy density of *** usage of energy storage can mitigate wind power fluctuations and reduce the requirement of out-delivery transmission capacity,but facing the issue of energy storage cost ***,it is necessary to optimize the allocation of energy storage while considering the problem of wind power *** paper studies the joint optimization of large-scale wind power transmission capacity and energy storage,reveals the mechanism of energy storage in order to reduce the power fluctuation of wind power base and slow down the demand of ***,analyze the multi-functional cost-sharing mode of energy storage,improve the efficiency of energy storage cost *** the coordination optimization configuration model to deal with the problem of large-scale wind power transmission capacity and energy storage,and realizes the transmission capacity optimization coordination and optimization with energy *** proposed method is verified by a wind base located in Northeast China.

关键词： Wind farm group energy storage configuration transmission capacity coordination and optimization