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Journal of Modern Power Systems and Clean Energy 2023年第6期11卷 1770-1783页

作者： Guozhou Zhang junbo zhao Weihao Hu Di Cao Nan Duan Zhe Chen Frede Blaabjerg School of Mechanical and Electrical Engineering University of Electronic Science and Technology of ChinaChengdu 610054China IEEE Department of Electrical and Computer Engineering University of ConnecticutStorrsCT06269USA Lawrence Livermore National Laboratory LivermoreUSA Department of Energy Technology Aalborg University9220 AalborgDenmark

This paper proposes a robust and computationally efficient control method for damping ultra-low frequency oscillations(ULFOs) in hydropower-dominated systems. Unlike the existing robust optimization based control formulation that can only deal with a limited number of operating conditions, the proposed method reformulates the control problem into a bi-level robust parameter optimization model. This allows us to consider a wide range of system operating conditions. To speed up the bi-level optimization process, the deep deterministic policy gradient(DDPG) based deep reinforcement learning algorithm is developed to train an intelligent agent. This agent can provide very fast lower-level decision variables for the upper-level model, significantly enhancing its computational efficiency. Simulation results demonstrate that the proposed method can achieve much better damping control performance than other alternatives with slightly degraded dynamic response performance of the governor under various types of operating conditions.

关键词： Bi-level robust parameter optimization deep reinforcement learning deep deterministic policy gradient ultralow frequency oscillation damping control stability

Correction of Time-varying PMU Phase Angle Deviation with Unknown Transmission Line Parameters

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CSEE Journal of Power and Energy Systems 2023年第1期9卷 315-325页

作者： Ancheng Xue He Kong Feiyang Xu junbo zhao Naichao Chang Joe H.Chow Haiyan Hong State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China Department of Electrical and Computer Engineering University of ConnecticutStorrs06268USA National Electric Power Dispatching and Control Center Beijing 100031China Department of Electrical Computerand Systems EngineeringRensselaer Polytechnic Institute(RPI)TroyNY 12180USA

Phasor measurement units(PMUs)provide useful data for real-time monitoring of the smart ***,there may be time-varying deviation in phase angle differences(PADs)between both ends of the transmission line(TL),which may deteriorate application performance based on *** address that,this paper proposes two robust methods of correcting time-varying PAD deviation with unknown parameters of TL(ParTL).First,the phenomena of time-varying PAD deviation observed from field PMU data are *** general formulations for PAD estimation are then *** simplify the formulations,estimation of PADs is converted into the optimal problem with a single ParTL as the variable,yielding a linear estimation of *** latter is used by second-order Taylor series expansion to estimate PADs *** reduce the impact of possible abnormal amplitude data in field data,the IGG(Institute of Geodesy&Geophysics,Chinese Academy of Sciences)weighting function is *** using both simulated and field data verify the effectiveness and robustness of the proposed methods.

关键词： Correction line parameters parameter identification phasor measurement time-varying phase angle difference deviation

Reinforcement Learning and Its Applications in Modern Power and Energy Systems: A Review

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Journal of Modern Power Systems and Clean Energy 2020年第6期8卷 1029-1042页

作者： Di Cao Weihao Hu junbo zhao Guozhou Zhang Bin Zhang Zhou Liu Zhe Chen Frede Blaabjerg the Wide-area Measurement and Control Sichuan Provincial Key Laboratory School of Mechanical and Electrical EngineeringUniversity of Electronic Science and Technology of ChinaChengduChina the Department of Electrical and Computer Engineering Mississippi State UniversityStarkvilleMississippiUSA the Department of Energy Technology Aalborg UniversityAalborgDenmark

With the growing integration of distributed energy resources(DERs),flexible loads,and other emerging technologies,there are increasing complexities and uncertainties for modern power and energy *** brings great challenges to the operation and ***,with the deployment of advanced sensor and smart meters,a large number of data are generated,which brings opportunities for novel data-driven methods to deal with complicated operation and control *** them,reinforcement learning(RL)is one of the most widely promoted methods for control and optimization *** paper provides a comprehensive literature review of RL in terms of basic ideas,various types of algorithms,and their applications in power and energy *** challenges and further works are also discussed.

关键词： Reinforcement learning deep reinforcement learning power system operation and control optimization

Status of congenital extrahepatic portosystemic shunt

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Chinese Medical Journal 2022年第13期135卷 1610-1612页

作者： Pan Zeng Zhenfan Qu Heng Sun junbo zhao Pediatric Surgery Graduate Training Base of Jinzhou Medical UniversityAffiliated Hospital of Hubei Medical CollegeTaihe HospitalShiyanHubei 442000China

To the Editor:Studies have demonstrated that congenital extrahepatic portosystemic shunt(CEPS)is a serious and life-threatening disease.[1]According to statistics,deformity,infection,liver failure,and failure of other systems are the main causes of death.[2]This article will introduce the pathology,classification,clinical manifestations,diagnosis,and treatment of CEPS.

关键词： congenital shunt diagnosis

Case Retrieval Strategy of Turning Process Based on Grey Relational Analysis

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1663-1678页

作者： Jianfeng zhao Yunliang Huo Ji Xiong junbo Liu Zhixing Guo Qingxian Li School of Mechanical Engineering Sichuan UniversityChengdu610065China Sichuan Engineering Technology Research Center of Intelligent Design and Service for Cutting Tools Yibin R&D Park of Sichuan UniversityYibin644000China Department of R&D Pengxi Heye High-Tech Co.Ltd.Suining629000China

To solve the problem of long response time when users obtain suitable cutting parameters through the Internet based platform,a case-based reasoning framework is ***,a Hamming distance and Euclidean distance combined method is designed to measure the similarity of case features which have both numeric and category *** addition,AHP(Analytic Hierarchy Process)and entropy weight method are integrated to provide features weight,where both user preferences and comprehensive impact of the index have been *** relation analysis is used to obtain the similarity of a new problem and alternative ***,a platform is also developed on Visual Studio 2015,and a case study is demonstrated to verify the practicality and efficiency of the proposed *** method can obtain cutting parameters which is suitable without iterative *** with the traditional PSO(Particle swarm optimization algorithm)and GA(Genetic algorithm),it can obtain faster response *** method can provide ideas for selecting processing parameters in industrial *** guaranteeing the characteristic information is similar,this approach can select processing parameters which is the most appropriate for the production process and a lot of time can be saved.

关键词： CBR turning process grey relation AHP entropy weight

Study on Lateral Aerodynamic Characteristics of Hypersonic Lifting-Configuration

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Journal of Energy and Power Engineering 2014年第12期8卷 2053-2057页

作者： Qing Gao Jianhua Li junbo zhao Qian Li The Second Department China Academy of Aerospace Aerodynamic Beijing 100074 China The Eleventh Department China Academy of Aerospace Aerodynamic Beijing 100074 China

To have a deep understanding of the lateral stability of hypersonic lifting-configurations, wind-tunnel tests of roll static and dynamic stability for typical hypersonic lifting-configurations are carried out. The results show the roll is static unstable in small angles; the roll dynamic test curves present obvious non-linearity characteristics, and the model vibrates violently even When the angle of attack is small, which may be provoked by the non-symmetry transition from the small transverse flow around the nose of model. Subsequent research adopts longitudinal trips to generate symmetry transition at the fore-body of the model. As a result, the lateral stability of the aircrafts is apparently improved. The results show that the lateral stability of hypersonic aircrafts is very weak, and the main reason for this is lateral perturbation of flow over the nose, among which asymmetric transition weighs the most. Adoption of longitudinal trips could spur fixed transition of lateral flow, reduce the transition asymmetry of lateral flow, and strengthen the lateral stability of hypersonic aircrafts at the same time.

关键词： Hypersonic lifting-configuration lateral stability wind-tunnel test asymmetric transition.

Twisted Phosphors that Violate Kasha's Exciton Model in Organic Systems

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Chinese Journal of Chemistry 2024年第11期42卷 1237-1246页

作者： Boyi Fu Guangming Wang Jiuyang Li junbo Li Xun Li Xiaoya zhao Shuhui Ding Guoping Yan Qianqian Yan Kaka Zhang School of Materials Science and Engineering Wuhan Institute of TechnologyWuhanHubei430205 China Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai200032 China

Kasha's exciton model proposes that T1 energy levels of organic compounds are insensitive to molecular aggregation and microenvironment change because of negligible small transition dipole moments of T1 *** model holds true in most organic systems till *** we report the fabrication of twisted organic phosphors with intramolecular charge transfer characters and flexible molecular *** doped into different organic matrices,the twisted phosphor adopts different conformation,exhibits distinct phosphorescence colors and T1 energy levels,which violates Kasha's exciton model in organic *** that the change of phosphorescence colors and maxima can be readily distinguished by human eyes and conventional instrument,the twisted phosphors would be exploited as a new type of molecular probe,which would exhibit potential application in optical sensing and stimuli-responsive systems.

关键词： Afterglow Twisted phosphor Triplet excited state Room-temperature phosphorescence Luminescence Spin-orbit coupling

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论刘咸炘文学研究的西学视野

四川师范大学学报（社会科学版） 2022年第6期49卷 187-195页

作者：赵俊波四川师范大学文学院

刘咸炘的文学研究具有广阔的西学视野。逻辑学方面,他强调写作中应注意逻辑,并以此为标准纵论中国古代名家名作;文学进化论方面,他认为中国文学并非线性进化,而是循环发展,且进化是旧“移”为新而非以新“代”旧;对西方古典主义、浪漫... 详细信息

刘咸炘的文学研究具有广阔的西学视野。逻辑学方面,他强调写作中应注意逻辑,并以此为标准纵论中国古代名家名作;文学进化论方面,他认为中国文学并非线性进化,而是循环发展,且进化是旧“移”为新而非以新“代”旧;对西方古典主义、浪漫主义等文学思潮以及鉴赏与批评论等,他既有赞同,也有异议。同时,他也有初步的中西文学比较的意识。在中西、新旧学术思潮百花齐放的时代,刘咸炘的文学研究以求真为目的,吸收西方学术思想中合理的部分,而摒弃其与中国文学的扞格之处,表现出独立、理性的学术气质。

关键词：刘咸炘《推十书》文学研究西学视野

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矿区GPS控制网的设计方案选择探讨

中国煤炭 2013年第4期39卷 36-39页

作者：赵军波冀中能源股份有限公司葛泉矿河北省邢台市054102

目前矿区等级控制网平面均采用GPS作业,高程采用水准测量或GPS拟合高程测量。由于1989年颁布的《煤矿测量规程》没有有关GPS测量的规定,故参考执行其他相关测量规范的条款规定势成必然。比较了现行《煤矿测量规程》、《全球定位系统(GPS... 详细信息

目前矿区等级控制网平面均采用GPS作业,高程采用水准测量或GPS拟合高程测量。由于1989年颁布的《煤矿测量规程》没有有关GPS测量的规定,故参考执行其他相关测量规范的条款规定势成必然。比较了现行《煤矿测量规程》、《全球定位系统(GPS)测量规范》、《地质矿产勘查测量规范》、《工程测量规范》的有关条款,通过对不同规范条款规定的对比,选择矿区控制网的设计方案。

关键词：矿区等级控制网测量规范 GPS控制网方案设计

多模式镇痛在小儿扁桃体腺样体切除术后的应用效果

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河南医学研究 2024年第8期33卷 1365-1369页

作者：卫明谦刘茜顾士敏高文龙刘博赵军博耿晓媛魏晓永郑州大学第三附属医院麻醉科河南郑州450052

目的观察多模式镇痛方法在小儿扁桃体腺样体切除术后的应用效果。方法选取在医院择期行扁桃体腺样体切除手术的90例患儿,术后均接受静脉自控镇痛(PCIA),依据随机数字表法分为3组,每组30例。给予S组舒芬太尼联合右美托咪定;给予T组酮咯... 详细信息

目的观察多模式镇痛方法在小儿扁桃体腺样体切除术后的应用效果。方法选取在医院择期行扁桃体腺样体切除手术的90例患儿,术后均接受静脉自控镇痛(PCIA),依据随机数字表法分为3组,每组30例。给予S组舒芬太尼联合右美托咪定;给予T组酮咯酸氨丁三醇联合右美托咪定;给予ST组舒芬太尼、酮咯酸氨丁三醇联合右美托咪定。记录3组手术时间、麻醉时间;记录3组术后4、8、12、24、48 h儿童疼痛行为评估量表(FLACC)评分、Ramsay镇静评分以及48 h内PCIA的总按压次数、有效按压次数、补救镇痛及不良反应的发生情况。结果与T组比较,术后4、8、12、24 h S组和ST组FLACC评分降低(P<0.05)。与S组比较,术后4、8、12、24、48 h T组和ST组Ramsay镇静评分降低(P<0.05);与ST组比较,术后4、8 h T组Ramsay镇静评分降低(P<0.05)。术后48 h内T组镇痛泵总按压次数和有效按压次数多于S组和ST组(P<0.05)。术后48 h内S组恶心呕吐、嗜睡、皮肤瘙痒的发生率高于T组和ST组(P<0.05),T组的补救镇痛率高于S组和ST组(P<0.05)。结论舒芬太尼复合酮咯酸氨丁三醇及右美托咪定的多模式镇痛方法用于扁桃体腺样体切除术后PCIA的效果较好,不良反应发生率低。

关键词：酮咯酸氨丁三醇舒芬太尼右美托咪定多模式镇痛

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