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Intelligent Predetermination of Generator Tripping Scheme: Knowledge Fusion-based Deep Reinforcement Learning Framework

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CSEE Journal of Power and Energy Systems 2024年第1期10卷 66-75页

作者： lingkang Zeng Wei Yao Ze Hu Hang Shuai Zhouping li Jinyu wen Shijie Cheng State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronics EngineeringHuazhong University of Science and TechnologyWuhan 430074China Dispatching and Control Center Central China Branch of State Grid Corporation of ChinaWuhan 430077China. Department of Electrical Engineering and Computer Science University of TennesseeKnoxvilleTN 37996USA

Generator tripping scheme(GTS)is the most commonly used scheme to prevent power systems from losing safety and ***,GTS is composed of offline predetermination and real-time scenario ***,it is extremely time-consuming and labor-intensive for manual predetermination for a large-scale modern power *** improve efficiency of predetermination,this paper proposes a framework of knowledge fusion-based deep reinforcement learning(KF-DRL)for intelligent predetermination of ***,the Markov Decision Process(MDP)for GTS problem is formulated based on transient instability ***,linear action space is developed to reduce dimensionality of action space for multiple controllable ***,KF-DRL leverages domain knowledge about GTS to mask invalid actions during the decision-making *** can enhance the efficiency and learning ***,the graph convolutional network(GCN)is introduced to the policy network for enhanced learning *** simulation results obtained on New England power system demonstrate superiority of the proposed KF-DRL framework for GTS over the purely data-driven DRL method.

关键词： Deep reinforcement learning generator tripping scheme graph convolutional network invalid action masking knowledgefusion

Constrained consensuses in disconnected topologies

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Chinese Physics B 2012年第2期21卷 581-590页

作者： Song Hai-Yu Yu li Hu Hong-Xiang Zhang wen-An College of Information Engineering Zhejiang University of Technology and Zhejiang Provincial United Key Laboratory of Embedded SystemsHangzhou 310023China

This paper is concerned with the constrained consensuses problem for a group of agents in disconnected topologies. By dividing the communication topology into a combination of directed trees, some necessary and sufficient conditions are derived for all the agents to asymptotically reach a single consensus and multiple consensuses, respectively. The obtained results indicate that arbitrary anticipant consensuses can be achieved, if additional constrained controllers are added to those agents with specific indexes. Some illustrative examples are provided to demonstrate the effectiveness of the proposed theoretical results.

关键词： disconnected topologies single consensus multiple consensuses

Surface modification of 316L stainless steeldiamond-like carbon films

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Journal of Iron and Steel Research International 2020年第7期27卷 867-874页

作者： Rui-wu li Zheng Zhang Jian-wei li Ke-xin Ma Yuan-yuan Guo Yan-wen Zhou Fa-yu Wu School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina liaoning Censcience Industrial Co. Ltd.Research and Design InstituteLiaoyang 111200LiaoningChina

The diamond-like carbon(DLC)film on 316L stainless steel substrate was preparedpulsed plasma-enhanced chemical vapor deposition,and the performance of the films was optimizedregulating the pulse *** and properties of DLC film on 316L stainless steel were characterizedatomic force microscopy,field-emission scanning electron microscopy,Raman spectra,nano-indenter and electrochemical *** results showed that DLC films with smooth and dense morphology have a low friction coefficient and high nano-indentation hardness,and the surface hardness of 316L stainless steel substrate was enhancedmore than 3 *** mechanical properties of DLC films and their bond with 316L stainless steel could be further optimizedincreasing pulse *** films on 316L stainless steel substrate increased the self-corrosion potential0.173 V and decreased self-corrosion current99%,which significantly improved the anti-corrosive properties of 316L substrate.

关键词： 316L stainless steel Diamond-like carbon film Plasma enhanced chemical vapor deposition Frictional wear Nano-indentation Corrosion resistance

Verification of workflow nets with transition conditions

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第7期13卷 483-509页

作者： Zhao-xia WANG Jian-min WANG Xiao-chen ZHU li-jie wen School of Software Tsinghua UniversityBeijing 100084China Department of Computer Science and Technology Tsinghua UniversityBeijing 100084China MOE Key Laboratory for Information System Security Tsinghua UniversityBeijing 100084China National Laboratory for Information Science and Technology Tsinghua UniversityBeijing 100084China SDepartment of Logistical Information&Engineering Logistical Engineering UniversityChongqing 400016China

Workflow management is concerned with automated support for business *** management systems are driven by process models specifying the tasks that need to be executed,the order in which they can be executed,which resources are authorised to perform which tasks,and data that is required for,and produced by,these *** workflow instances may run over a sustained period of time,it is important that workflow specifications be checked before they are *** verification is usually concerned with control-flow dependencies only;however,transition conditions based on data may further restrict possible choices between *** this paper we extend workflow nets where transitions have concrete conditions associated with them,called *** then demonstrate that we can determine which execution paths of a WTC-net that are possible according to the control-flow dependencies,are actually possible when considering the conditions based on ***,we are able to more accurately determine at design time whether a workflow net with transition conditions is sound.

关键词： Workflow nets Transition condition Verification Process model

The design,mechanism and biomedical application of self-healing hydrogels

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Chinese Chemical Letters 2017年第9期28卷 1857-1874页

作者： Qiwen li Chenlu liu Junru wen Yongzhi Wu Yue Shan Jinfeng liao State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesWest China Hospital of StomatologySichuan University Laboratory of Molecular and Translational Medicine Key Laboratory of Birth Defects and Related Diseases of Women and Children of Ministry of Education at Sichuan UniversityWest China Second University HospitalSichuan University

Hydrogels are promising materials with outstanding characteristics such as tunable and reversible physical/chemical properties,stimuli-responsiveness,biomimetic,and ***,the structural and functional integrity of the hydrogels can be compromised by external mechanical forces or chemical erosion when used,especially in sophisticated in vivo *** address this problem,self-healing hydrogels which possess the intrinsic ability of self-repair have been developed to adapt to destructive *** this review,we focused on the current advances made in self-healing ***,the testing methods for self-healing hydrogels were ***,we looked into the designing strategies of self-healing hydrogels and illustrated the self-healing ***＇s more,the biomedical application of self-healing hydrogels in vivo was discussed.

关键词： Self-healing Hydrogels Chemical mechanism Biomaterials In vivo

Measurement of R line Fluorescence in Ruby Using the Diamond Anvil Cell at Low Temperature

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Chinese Physics Letters 2000年第8期17卷 555-557页

作者： XU li-wen CHE Rong-Zheng JIN Chang-Qing Institute of Physics and Center for Condensed Matter Chinese Academy of SciencesBeijing 100080

Using our custom-built high-pressure cryostat we have performed the measurements of the R line fluorescence of ruby in the diamond anvil cell from room temperature down to *** maximum pressure was 11.1 *** computer curve fitting,different equations have been found for functions of wavenumber versus temperature between ambient pressure and 2.7 *** changes of the shape and linewidth of R lines were observed.

关键词： Diamond Fluorescence ambient

Effects of Forest Roads on Habitat Pattern for Sables in Da Hinggan Mountains, Northeasten China

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Chinese Geographical Science 2014年第5期24卷 587-598页

作者： li Yuehui WU wen XIONG Zaiping HU Yuanman CHANG Yu XIAO Duning State Key Laboratory of Forest and Soil Ecology Institute of Applied Ecology Chinese Academy of Sciences University of Chinese Academy of Sciences

The anthropogenic managements of forest have created a network of roads resulting in the loss and alternation of habitat. To better understand road′s impact on animal habitats, we assessed the habitat pattern of sables(Martes zibellina), one of rodents within national first-class protected species, when roads are considered in Huzhong area in Da Hinggan Mountains, northeastern China. Employing published literatures about behavior ecology, aerial photographs and forest stand maps, we classified the study area into three habitat types including best-suitable, suitable and unsuitable habitats based on sable habitat requirements at the landscape scale including four variables derived from forest source map with attribute database. Results indicated the loss and significant fragmentation of best-suitable habitat and home range habitat when roads, especially 150 m avoidance distance of roads, were considered. The roads reduced and fragmented highly suitable habitats more significantly during earlier development period than the later development period. Additionally, the suitable area percentage increased with increasing distance to roads. This study helped to identify the suitable area for sables and location of sable population. Also, this study suggested the passage construction and road management involving road closure and removal will reduce the fragmentation functionally and benefit the sable population.

关键词： forest road sable habitat pattern buffer analysis Da Hinggan Mountains

Extraction of Alpha transmitter signals from single-station observations using the direction-finding method

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Science China(Technological Sciences) 2022年第8期65卷 1727-1737页

作者： GU XuDong CHEN Huan WANG ShiWei LU ZiLong NI BinBin li GuangJian CHENG wen Department of Space Physics School of Electronic InformationWuhan UniversityWuhan 430072China

For the applications of Alpha very-low-frequency(VLF) systems consisting of multiple transmitters, determining the origin transmitter station of received signals is a crucial problem. Based on single-station observations, this study develops a directionfinding method to extract Russian Alpha transmitter signals. First, the amplitudes of Alpha signals received in Suizhou City,Hubei Province(31.57°N, 113.32°E) in the east-west(EW) and north-south(NS) directions are obtained by the power spectrum method. The amplitude ratios of signals in the two directions are subsequently adopted to estimate the propagation angles of the signals with respect to the NS direction of the VLF receiver station. Phase ambiguity in our system is eliminated by comparing Alpha signal waveform with that from the VTX transmitter in India(8.39°N, 77.75°E) as a reference station. Finally, we can determine the quadrant where the incoming wave signals are located relative to the receiver and eventually distinguish the exact Alpha transmitters. Based on the direction-finding results, the amplitudes of each Alpha signal are extracted, and their diurnal variation features are analyzed to verify the performance of our method. These results are of great significance for the further study of Alpha signals and VLF long-distance communication.

关键词： very low frequency signal alpha transmitter direction-finding method single-station observation

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Facile synthesis of hollow Cu_(3)P for sodium-ion batteries anode

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Rare Metals 2021年第12期40卷 3460-3465页

作者： Jiao-Long Zhang Chao-lin li wen-Hui Wang Denis Y.W.Yu School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China Shenzhen Key Laboratory on Power Battery Safety Research and Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolShenzhen 518055China School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhen 518055China School of Energy and Environment City University of Hong KongHong Kong 999077China

Combining metal to form metal phosphide is a promising strategy to address the fast capacity decay of P rooted from its low electronic conductivity and large volume changes upon cycling. Cu_(3)P, which possesses a high theoretical gravimetric and volumetric capacity of 363 m Ahág^(-1) and 1028 AháL^(-1) and reasonable volume expansion of 156% during sodiation, was investigated as anode material in SIBs. Hollow-structured Cu_(3)P electrode delivers an initial de-sodiation capacity of * 159.0 m Ahág^(-1) with high capacity retention of ~85.1% over 50 cycles at 0.2 C rate and exhibits good rate performance,retaining 70% of the capacity when the current density increases from 0.2 C to 1.6 C. A 3 V-class full cell consisting of P2-Na_(2/3) Ni_(1/3) Mn_(1/2) Ti_(1/6)O_(2) cathode and Cu_(3)P anode was also assembled, which could achieve an energy density of ~189.3 Whákg^(-1)(based on the mass of both electrode materials) and average discharge voltage of~2.91 V when cycled in 1.0-4.3 V at 0.1C.

关键词： Na-ion battery Anode Phosphorus Cu_(3)P Hollow