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Permeability variation characteristics of coal after injecting carbon dioxide into a coal seam

International Journal of Mining Science and Technology 2015年第4期25卷 665-670页

作者： Ni Xiaoming Li Quanzhong Wang yanbin Gao Shasha School of Energy Science and Engineering Henan Polytechnic University Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region College of Geoscience and Surveying Engineering China University of Mining & Technology

A theoretical basis for the optimization of carbon dioxide injection parameters and the development of the drainage system can be provided by identifying the permeability change characteristic of coal and rock after injection of carbon dioxide into the coal seam. Sihe, Yuwu, and Changcun mines were used as research sites. Scanning electron microscopy and permeability instruments were used to measure coal properties such as permeability and surface structure of the coal samples at different pH values of carbon dioxide solution and over different timescales. The results show that the reaction between minerals in coal and carbonate solution exhibit positive and negative aspects of permeability-the dissolution reaction between carbonate minerals in coal and acid solution improves the conductivity of coal whilst, on the other hand, the clay minerals in the coal （mainly including montmorillonite, illite and kaolinite） exhibit expansion as a result of ion exchange with the H~ in acid solution, which has a negative effect on the per- meability of the coal. The permeability of coal samples increased at first and then decreased with immer- sion time, and when the soaking time is 2-3 months the permeability of the coal reached a maximum. In general, for coals with permeabilities less than 0.2 mD or greater than 2 roD, the effect on the permeabil- ity is low： when the permeability of the coal is in the range 0.2-2 mD, the effect on the permeability is highest. Research into permeability change characteristics can provide a theoretical basis for carbon diox- ide injection under different reservoir permeability conditions and subsequent drainage.

关键词： Carbon dioxide Coal reservoir Permeability Change characteristics

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Incorporating metapath interaction on heterogeneous information network for social recommendation

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Frontiers of Computer Science 2024年第1期18卷 33-48页

作者： yanbin JIANG Huifang MA Xiaohui ZHANG Zhixin LI Liang CHANG College of Computer Science and Engineering Northwest Normal UniversityLanzhou 730070China Guangxi Key Lab of Multi-source Information Mining and Security Guangxi Normal UniversityGuilin 541001China Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China

Heterogeneous information network(HIN)has recently been widely adopted to describe complex graph structure in recommendation systems,proving its effectiveness in modeling complex graph *** existing HIN-based recommendation studies have achieved great success by performing message propagation between connected nodes on the defined metapaths,they have the following major *** works mainly convert heterogeneous graphs into homogeneous graphs via defining metapaths,which are not expressive enough to capture more complicated dependency relationships involved on the ***,the heterogeneous information is more likely to be provided by item attributes while social relations between users are not adequately *** tackle these limitations,we propose a novel social recommendation model MPISR,which models MetaPath Interaction for Social Recommendation on heterogeneous information ***,our model first learns the initial node representation through a pretraining module,and then identifies potential social friends and item relations based on their similarity to construct a unified *** then develop the two-way encoder module with similarity encoder and instance encoder to capture the similarity collaborative signals and relational dependency on different *** experiments on five real datasets demonstrate the effectiveness of our method.

关键词： heterogeneous information network social reco-mmender system metapath interaction attention mechanism

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A hybrid quantum-based PIO algorithm for global numerical optimization

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Science China(Information Sciences) 2019年第7期62卷 33-44页

作者： Boyi CHEN Hao LEI Haidong SHEN yanbin LIU Yuping LU College of Astronautics Nanjing University of Aeronautics and Astronautics College of Automation Engineering Nanjing University of Aeronautics and Astronautics

A novel hybrid quantum-based pigeon-inspired optimization(PIO) algorithm for global numerical optimization is proposed to perceive deceptiveness and preserve diversity. In the proposed algorithm,the current best solution is regarded as a linear superposition of two probabilistic states, namely positive and deceptive. Through a quantum rotation gate, the positive probability is either enhanced or reset to balance exploration and exploitation. Simulation results reveal that the hybrid quantum-based PIO algorithm demonstrates an outstanding performance in global optimization owing to preserving diversity in the early evolution. As a result, the stability of the algorithm is enhanced so that the precision of optimization is improved statistically. The proposed algorithm is demonstrated to be effective for solving multimodal and non-convex problems in higher dimension with a smaller population size.

关键词： PIO global convergence numerical optimization QEA

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Conjoint analysis of crowbar switching scheme and its resistancebased on statistical sampling for LVRT of DFIG

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Journal of Modern Power Systems and Clean Energy 2019年第3期7卷 558-567页

作者： yanbin QU Le GAO Guangfu MA Huihui SONG Shitao WANG School of Information and Electrical Engineering Harbin Institute of Technology at WeihaiNo.2West Wenhua RoadWeihai 264209China Department of Control Science and Engineering Harbin Institute of TechnologyNo.92West Dazhi StreetNangang DistrictHarbin 150001China State Grid of China Technology College No.500ErhuanSouth RdJinanChina

An active crowbar protective circuit is an effective and common approach for low voltage ride through(LVRT) of a doubly-fed induction generator(DFIG). The crowbar resistance value and its switching scheme both have crucial effects on safety recovery. The effects encountered are correlative dependence and interplay so that analyzing them from a single factor, as most existing LVRT control methods would do, obtains a partial optimal solution. This paper combines these two factors toanalyze their coordination effects on the LVRT control,and to also investigate whether the global optimal performance of these factors can be achieved. The principles for resistance selection and the schemes for crowbar switching are discussed first. Next, the coupling relationship is ana-lyzed based on statistical sampling simulation data with different resistance values and various switching *** results demonstrate that their coordination has critical influence on rotor peak current, DC-link voltage and reactive power. The optimal coordination will be different according to specific requirements. Hence the global optimal combination could be achieved when all requirements are taken into consideration.

关键词： Doubly-fed induction generator(DFIG) Active crowbar Switching scheme Resistance value Statistical sampling data

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Ultrafast room-temperature reduction of graphene oxide by sodium borohydride,sodium molybdate and hydrochloric acid

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Chinese Chemical Letters 2021年第1期32卷 543-547页

作者： Jun Hu Gang Kong yanbin Zhu Chunshan Che School of Materials Science and Engineering South China University of TechnologyGuangzhou 510641China

Since graphene-based materials have shown great potential in many fields,it is important to explore ultrafast and high-efficient methods to synthesize reduced graphene oxide(rGO) using inexpensive reducing agents under mild ***,we reported a novel method for the ultrafast chemical reduction of graphene oxide(GO) at room temperature using sodium borohydride(NaBH_(4)),sodium molybdate(Na_(2)MoO_(4)) and hydrochloric acid(HCl).The reduction was carried out within 2 min.A series of characterization results revealed that the obtained reduced graphene oxide has higher reduction degree than that synthesized by NaBH_(4) alone at high ***,rGO electrode based on the present reducing method exhibited a superior specific capacitance of 139.8 F/g at a current density of1 A/g,indicating that it can be used as electrode materials for supercapacitors.

关键词： Carbon materials Reduced graphene oxide Sodium borohydride Sodium molybdate Hydrochloric acid Supercapacitors

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Carbon and water fluxes in ecologically vulnerable areas in China

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Journal of Plant Ecology 2022年第5期15卷 879-881页

作者： Zhongmin Hu Shiping Chen yanbin Hao Key Laboratory of Agro-Forestry Environmental Processes and Ecological Regulation of Hainan Province Hainan UniversityHaikou 570228China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai 519082China State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China

Ecologic vulnerable areas(EVAs)are the regions where ecosystems are fragile and vulnerable to sufferfrom degradation with external disturbances,*** changes and human activities(Fengetal.2022;Wangetal.2019).EVAsinChina are widely distributed and account for more than 55%China's landarea(Ministryof Ecologyand Environment of the People's Republic of China 2008).Theecosystem in EVAs,chartered with low stability,weak resistance and high vulnerability,has been experiencing significant degradation owing to the impacts of global climate change and human activities(Bai et al.2018;Chen et al.202l;Yuetal.2022).

关键词： al. vulnerable degradation

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Satellite group autonomous operation mechanism and planning algorithm for marine target surveillance

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Chinese Journal of Aeronautics 2019年第4期32卷 991-998页

作者： Chao ZHANG Jinyong CHEN yanbin LI Yuqing LI Weijie CHAI CETC Key Laboratory of Aerospace Information Applications The 54th Research Institute of China Electronics Technology Group Corporation Deep Space Exploration Research Center Harbin Institute of Technology

In terms of fast response problem of unanticipated marine target, it is necessary to design the satellite-ground-combined operation mechanism and planning algorithm for autonomous task planning. Firstly, based on the autonomous operation and task planning of remote sensing satellite group, it is divided into two parts: ground planning and satellite autonomous planning. Secondly,the satellite-ground-combined operation mechanism and operation flow for task planning are proposed after fully considering the resource characteristics and task demand characteristics of the ground and satellite. The satellite autonomous task planning algorithm based on extended contract net is designed. Through the simulation operation of the self-developed distributed simulation demonstration software, it shows that the operation mechanism can coordinate and cooperate effectively between the satellite autonomous task planning and ground planning. It can give full play to the advantages of the ground computing resources, reflect the control intention, make full use of the real-time feature and flexibility of the satellite calculation, and respond fast to the unanticipated task. Besides, it has solved problems of the untimely response of ground control on unanticipated observation task, the limitation of satellite computing resources and satellite-ground planning and coordination, which can effectively improve the responsiveness of remote sensing satellite to the observation task of maritime unanticipated target.

关键词： Fast response Marine target surveillance Mission planning Multi-satellite system Onboard autonomy

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Study of crystalline silicon solar cells with integrated bypass diodes

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Science China(Technological Sciences) 2012年第3期55卷 594-599页

作者： CHEN KaiHan CHEN DaMing ZHU yanbin SHEN Hui State Key Laboratory of Optoelectronic Materials and Technologies Institute for Solar Energy SystemsSun Yat-Sen UniversityGuangzhou 510275China

This paper reported a novel method of integrating bypass diodes into crystalline silicon solar *** diodes which have the opposite p-n junction were formed by printing specific paste on the local surface of solar cells using screen printing,while infrared laser was applied to isolate the diode from the cell after firing.A module of crystalline silicon solar cells with integrated bypass diodes was fabricated and the I-V characteristics were measured under different shade *** experimental results clearly showed that the integrated bypass diodes can effectively stabilize module's short circuit current while reduce the module power loss when shaded as well.

关键词： crystalline silicon solar cells bypass diode integration

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Twistor-based synchronous sliding mode control of spacecraft attitude and position

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Chinese Journal of Aeronautics 2018年第5期31卷 1153-1164页

作者： Qing LI Lei LIU Yifan DENG Shuo TANG yanbin ZHAO Shaanxi Aerospace Flight Vehicle Design Key Laboratory School of Astronautics Northwestern Polytechnical UniversityXi'an 710072 China Shanghai Institute of Satellite Engineering Shanghai 200240 China

A synchronous control of relative attitude and position is required in separated ultraquiet spacecraft, such as drag-free, disturbance-free, and distributed spacecraft. Thus, a twistorbased synchronous sliding mode control is investigated in this paper to solve the control problem of relative attitude and position among separated spacecraft modules. The twistor-based control design and the stability proof are implemented using the Modified Rodrigues Parameter（MRP）.To evaluate the effectiveness of the proposed control method, this paper presents a case study of separated spacecraft flying control considering the mass uncertainty and external disturbances. In addition, a simulation study of the Proportional-Derivative（PD） control is also presented for comparison. The results indicate that the twistor-based sliding mode controller can ensure global asymptotic stability. The states converge fast with ultra-precision and ultra-stability in both the attitude and position. Moreover, the proposed twistor-based sliding mode control system is robust to the mass uncertainty and external disturbances.

关键词： Distributed spacecraft Gravitational wave detection Synchronous control Ultra-precision Ultra-stability

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Identifying Industrial Control Equipment Based on Rule Matching and Machine Learning

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Computer Modeling in Engineering & Sciences 2023年第10期137卷 577-605页

作者： Yuhao Wang Yuying Li yanbin Sun Yu Jiang Cyberspace Institute of Advanced Technology(CIAT) Guangzhou UniversityGuangzhou510006China

To identify industrial control equipment is often a key step in network mapping,categorizing network resources,and attack *** example,if vulnerable equipment or devices can be discovered in advance and the attack path canbe cut off,security threats canbe effectively avoided and the stable operationof the Internet canbe *** existing rule-matching method for equipment identification has limitations such as relying on experience and low *** paper proposes an industrial control device identification method based on PCA-Adaboost,which integrates rule matching and machine *** first build a rule base from network data collection and then use single andmulti-protocol rule-matchingmethods to identify the type of industrial control ***,we utilize PCA-Adaboost to identify unlabeled *** experimental results show that the recognition rate of this method is better than that of the traditional Nmap device recognitionmethod and the device recognition accuracy rate reaches 99%.The evaluation effect of the test data set is significantly enhanced.

关键词： Network mapping network resource industrial control equipment identification

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