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High Voltage 2024年第2期9卷 380-390页

作者： Xinyu Wang Ping Wang Jianghai Geng Zikang Zhang Fangcheng Lü Shuguo Gao Hebei Provincial Key Laboratory of Power Transmission Equipment Security Defense North China Electric Power UniversityBaodingChina State Grid Hebei Electric Power Research institute ShijiazhuangChina

Transformers may suffer multiple short-circuit impacts during long-term operation,and axial instability is one of the typical types of serious accidents caused by short-circuit *** axial instability form of the winding-block structure is analysed,and the dynamic solution of the winding short-circuit electromagnetic force is obtained by estab-lishing the three-dimensional magnetic-circuit-force multi-physical field coupling simulation *** influence of strain rate on the cushion block constitutive equation is corrected,and the modified model is verified by short-circuit impact test and quasi-static *** research results show that for 110 kV 31.5 MVA transformers,the maximum electromagnetic axial resultant force of winding is 363.16 kN,and the ultimate tilt force is 1214.2 *** pre-tightening force configuration is accordingly recom-mended to range from 363.16 to 608.28 kN,which is narrowed by 18.49%compared with the static calculation method;Meanwhile,adding a logarithmic strain rate correction term to the classical constitutive equation of the cushion block can achieve a good correction of the stress-strain relationship with the coefficient of determination above 0.99,and the cushion block has a larger elastic modulus under high strain rate *** research results provide an important theoretical reference for the axial stability structure of transformers.

关键词： axial correction structure

The effect of seismic action on stability of saline soil subgrade in cold region based on isothermal stratification method

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Earthquake Research Advances 2024年第3期4卷 66-81页

作者： Jie Cheng Yu Zhang Ying Ma Xuerui Chen Ning An School of Traffic and Transportation Lanzhou Jiaotong UniversityLanzhou730070China Key Laboratory of railway Industry of Plateau railway Transportation Intelligent Management and Control Lanzhou Jiaotong UniversityLanzhou730070China Gansu institute of Engineering Geology Lanzhou730030China

With the change of seasons, the shear strength of saline soil subgrade filler will change with the change of external temperature, which will aggravate the adverse effects of seismic on the subgrade. To explore the influence of seismic action on the stability of saline soil subgrade under the influence of temperature on the strength of saline soil subgrade filler, this paper first carried out saline soil shear tests at different temperatures to obtain the influence of temperature on the shear strength of saline soil. Then, the temperature field of the saline soil subgrade was simulated, and then based on the subgrade isothermal stratification model and FLAC3D, the displacement and acceleration amplification effects of seismic action on the shady slope, sunny slope and subgrade of saline soil subgrade in different months were analyzed. The following conclusions were finally drawn: under the action of seismic, In the process of the change of subgrade temperature of Qarhan-Golmud Expressway between 7.7°C and 27°C, the change of saline soil cohesion is the main factor affecting the stability of subgrade slope, and the maximum and minimum values of subgrade surface settlement appear in September and June of each year,respectively. In August, the differences of settlement between the shady slope and the sunny slope shoulder of the subgrade were the largest, and the acceleration of the shady slope and the sunny slope and the inside of the subgrade changed most significantly in the vertical direction. Special attention should be paid to the seismic early warning in the above key months;In the range from both sides of the shoulder to the centerline of the roadbed,the acceleration amplification effect starts to increase significantly from about 3m from the centerline of the roadbed to the centerline, so it is necessary to pay attention to the seismic design of this range.

关键词： Subgrade stability Saline soils Acceleration amplification effect Seismic design

Multi-area Frequency-constrained Unit Commitment for Power Systems with High Penetration of Renewable Energy Sources and Induction Machine Load

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Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 754-766页

作者： Leibao Wang Hui Fan Jifeng Liang Longxun Xu Tiecheng Li Peng Luo Bo Hu Kaigui Xie the State Grid Hebei Electric Power Research institute Shijiazhuang 050021China State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400044China

The increasing penetration of renewable energy sources(RESs)brings great challenges to the frequency security of power *** traditional frequency-constrained unit commitment(FCUC)analyzes frequency by simplifying the average system frequency and ignoring numerous induction machines(IMs)in load,which may underestimate the risk and increase the operational *** this paper,we consider a multiarea frequency response(MAFR)model to capture the frequency dynamics in the unit scheduling problem,in which regional frequency security and the inertia of IM load are modeled with high-dimension differential algebraic equations.A multi-area FCUC(MFCUC)is formulated as mixed-integer nonlinear programming(MINLP)on the basis of the MAFR ***,we develop a multi-direction decomposition algorithm to solve the MFCUC *** original MINLP is decomposed into a master problem and *** subproblems check the nonlinear frequency dynamics and generate linear optimization cuts for the master problem to improve the frequency security in its optimal *** studies on the modified IEEE 39-bus system and IEEE 118-bus system show a great reduction in operational ***,simulation results verify the ability of the proposed MAFR model to reflect regional frequency security and the available inertia of IMs in unit scheduling.

关键词： Decomposition algorithm frequency response frequency-constrained unit commitment induction machine multi-area mixed-integer nonlinear programming(MINLP)

On the Polygonal Wear Evolution of Heavy-Haul Locomotive Wheels due to Wheel/Rail Flexibility and Its Mitigation Measures

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Chinese Journal of Mechanical Engineering 2024年第1期37卷 40-61页

作者： Yunfan Yang Feifan Chai Pengfei Liu Liang Ling Kaiyun Wang Wanming Zhai State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang 050043China State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

Wheel polygonal wear can immensely worsen wheel/rail interactions and vibration performances of the train and track,and ultimately,lead to the shortening of service life of railway *** present,wheel/rail medium-or high-frequency frictional interactions are perceived as an essential reason of the high-order polygonal wear of railway wheels,which are potentially resulted by the flexible deformations of the train/track system or other external *** this work,the effect of wheel/rail flexibility on polygonal wear evolution of heavy-haul locomotive wheels is explored with aid of the long-term wheel polygonal wear evolution simulations,in which different flexible modeling of the heavy-haul wheel/rail coupled system is ***,the mitigation measures for the polygonal wear of heavy-haul locomotive wheels are *** results point out that the evolution of polygonal wear of heavy-haul locomotive wheels can be veritably simulated with consideration of the flexible effect of both wheelset and *** of mixed-line operation of heavy-haul trains and application of multicut wheel re-profiling can effectively reduce the development of wheel polygonal *** research can provide a deep-going understanding of polygonal wear evolution mechanism of heavy-haul locomotive wheels and its mitigation measures.

关键词： Heavy-haul locomotive Wheel polygonal wear Wheel/rail flexibility Long-term polygonal wear evolution Mitigation measures

Identification of Motor Nuclei in the Medulla Oblongata of Carp for Biological Control

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Journal of Bionic Engineering 2024年第2期21卷 842-851页

作者： Yang Zhao Yong Peng Yudong Wen Lingjun Han Yanhong Yan Xueying Dong Hui Zhang Zheng Zhao Xiaoyue Liu School of Electrical Engineering Yanshan UniversityQinhuangdao066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao066004China Key Laboratory of National Defense of Mechanical Structure and Material Science Under Extreme Conditions Yanshan UniversityQinhuangdao066004China institute of Marine Science and Engineering Yanshan UniversityQinhuangdao066004China shijiazhuang University Shijiazhuang050035China

Brain-controlled technology is the key technology in biological control,and the corresponding relationship between animal brain nuclei and motor behavior is the *** purpose of this study was to explore the motor nuclei of the medulla oblongata in *** carps were subjected to electrical stimulation and chemical stimulation experiments,respectively,in the water-free state,and the effective chemical stimulation sites were injected with the pontamine sky blue *** brain tissue sections were obtained by paraffin tissue section technology and the neutral red staining *** comparing the positions of the brain nuclei shown in earlier studies,the motor nerve nuclei in the medulla oblongata were *** brain electrode was implanted into the motor nucleus of the medulla oblongata,and the underwater control experiment and behavioral tests were carried out with different electrical stimulation *** results showed that the abducens nucleus(NVI)was the motor nucleus that controls the ipsilateral steering,and the facial nucleus(NVII)was the motor nucleus that controls the forward *** adjusting the stimulation voltage and the stimulation pulse number,the carp can be stably controlled to achieve a left–right steering motion of 30°–180°and a forward motion of more than 80 cm/*** study indicated that the quantitative control of the steering and forward behavior of the carp can be achieved by electrical stimulation of the NVI and NVII,which provided a certain experimental basis for the accurate control of the carp robot.

关键词： Biological control Carp Medulla oblongata motor nucleus Electrical stimulation technique Chemical stimulation technique

Alarm Log Data Augmentation Algorithm Based on a GAN Model and Apriori

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Journal of Computer Science & Technology 2024年第4期39卷 951-966页

作者： Yang Yang Yu-Ting Li Yong-Hua Huo Zhi-Peng Gao Lan-Lan Rui State Key Laboratory of Network and Switching Technology Beijing University of Posts and TelecommunicationsBeijing 100876China The 54th Research institute of China Electronics Technology Group Corporation Shijiazhuang 050081China

The complexity of alarm detection and diagnosis tasks often results in a lack of alarm log *** to the strong rule associations inherent in alarm log data,existing data augmentation algorithms cannot obtain good results for alarm log *** address this problem,this paper introduces a new algorithm for augmenting alarm log data,termed APRGAN,which combines a generative adversarial network(GAN)with the Apriori *** generates alarm log data under the guidance of rules mined by the rule ***,we propose a new dynamic updating mechanism to alleviate the mode collapse problem of the *** addition to updating the real reference dataset used to train the discriminator in the GAN,we dynamically update the parameters and the rule set of the Apriori algorithm according to the data generated in each *** extensive experimentation on two public datasets,it is demonstrated that APRGAN surpasses other data augmentation algorithms in the domain with respect to alarm log data augmentation,as evidenced by its superior performance on metrics such as BLEU,ROUGE,and METEOR.

关键词： data augmentation alarm log data Apriori generative adversarial network(GAN)

Groundwater recharge via precipitation in the Badain Jaran Desert,China

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Journal of Groundwater Science and Engineering 2024年第1期12卷 109-118页

作者： Zhe Wang Li-juan Wang Jian-mei Shen Zhen-long Nie Le Cao Ling-qun Meng institute of Hydrogeology and Environmental Geology Chinese Academy of Geological SciencesShijiazhuang 050061China Technology Innovation Center for Geothermal&Hot Dry Rock Exploration and Development Ministry of Natural ResourcesShijiazhuang 050061China

Precipitation infiltration serves as a significant source of groundwater in the Badain Jaran *** investigate variations in precipitation infiltration within the desert,this study collected data on moisture content and temperature from the vadose zone through in-situ field *** these data,a numerical model is employed to explore the mechanism of groundwater recharge via *** results are as follows:(1)Moisture content and temperature in the shallow vadose zone exhibit significant seasonal variations,with moisture content diminishing with increasing depth;(2)Groundwater recharge via precipitation infiltration initially increases and then decreases with groundwater level depth(GWD).Peak groundwater recharge via precipitation occurs at a GWD of 0.75 m,decreasing to merely 0.012 cm at GWDs exceeding 2 m;(3)Groundwater is no longer susceptible to phreatic water evaporation when the GWD reaches approximately 3.7 ***,GWD plays a crucial role in governing groundwater recharge via precipitation in the Badain Jaran Desert.

关键词： Badain Jaran Desert Vadose zone Groundwater recharge In situ monitoring Numerical simulation

An improved elastoplastic model for rocks and application to cyclic loading and unloading triaxial compression tests

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Acta Mechanica Sinica 2024年第8期40卷 179-193页

作者： Qiuxin Gu Qiang Zhang Yapeng Li Peinan Wu Guilei Han State Key Laboratory for Geomechanics and Deep Underground Engineering School of Mechanics and Civil EngineeringChina University of Mining and TechnologyXuzhou221116China North China Engineering Investigation institute Shijiazhuang050021China

The recoverable strain of rock is completely classified as elastic strain in the conventional elastic-plastic theory,which often results in poor agreement between theoretical and experimental *** work proposes an improved elastoplastic model of rock materials considering the evolutions of crack deformation and elastic modulus to better characterize the nonlinear mechanical behavior of rock in the post-peak *** this model,the recoverable strain is assumed to be a combination of elastic and crack strain,and the constitutive relationship between crack strain and rock stress is *** on the proposed assumption,the evolutions of the mechanical parameters including strength parameters,elastic,plastic,and crack deformation parameters versus the plastic strain and confining stress were *** developed elastoplastic model was validated by comparing the theoretical values with the results of the triaxial cyclic loading and unloading *** theoretical calculation results show a good agreement with the laboratory test,which indicates that the improved elastoplastic model can effectively reflect the nonlinear mechanical behavior of the rock *** research results are expected to provide a valuable reference for further understanding the evolution of rock crack deformation.

关键词： Crack strain Elastic modulus deterioration Novel elastoplastic model Model validation

Experimental study on mix proportion optimization of anti-calcium dissolution shotcrete for tunnels based on response surface methodology

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Underground Space 2024年第2期15卷 203-220页

作者： Chongming Tian Yueping Tong Junyuan Zhang Fei Ye Guifeng Song Yin Jiang Meng Zhao School of Highway Chang’an UniversityXi’an 710064China Yunnan Laman Expressway Co. Ltd.Yunnan Xishuangbanna 666300China Hebei Traffic Planning Design institute Shijiazhuang 050035China

Aiming at the issue of crystallization and blockage of drainage system due to the massive calcium loss from the tunnel shotcrete,a selfdesigned tunnel seepage crystallization modelling system was *** system was produced in conjunction with the initial tunnel support shotcrete construction and drainage pipe installation,and is capable of simulating both the seepage process of groundwater in the shotcrete and the process of crystallization in the drainage *** on three different mechanisms of anti-crystallization,which include absorbing free calcium,reducing the porosity and increasing hydrophobicity,antialkali agent,nano-calcium carbonate,and silane were selected to test,***,the suitable dosing ranges of these three external admixtures for resisting calcium loss in shotcrete were determined by single factor tests,which were 7%–11%,4%–8%,and 0.3%–0.5%,***,the response surface method was employed to evaluate the interaction of antialkali agent,nano-calcium carbonate and silane on calcium loss in shotcrete,and to establish the relationship between them,and thus to determine the admixture ratio that can effectively reduce calcium loss crystallization in shotcrete,with the optimal admixture amounts of antialkali agent being 9.242%,nano-calcium carbonate 4.889%and silane 0.366%.Lastly,the reliability of the model test results was verified by the microscopic analysis,and the results showed that the total amount of calcium dissolution in the optimized group could be reduced by 75%compared with the blank control group,and was basically consistent with that derived from the response surface regression model,validating the high accuracy of the buildup response surface regression *** present study can provide some ideas and references for reducing the seepage crystallization behavior of groundwater in the initial tunnel support shotcrete.

关键词： Tunnel engineering Calcium loss Crystallization blockage Model test Response surface methodology Interaction effect

Artificial-intelligent-powered safety and efficiency improvement for controlling and scheduling in integrated railway systems

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High-Speed railway 2024年第3期2卷 172-179页

作者： Jun Liu Gehui Liu Yu Wang Wanqiu Zhang Beijing National railway Research&Design institute of Signal&Communication Group Co.Ltd. Beijing 100070China Engineering Research Center of railway Industry of Intelligent and Autonomous Train Control Beijing 100070China

The multi-mode integrated railway system,anchored by the high-speed railway,caters to the diverse travel requirements both within and between cities,offering safe,comfortable,punctual,and eco-friendly transportation *** the expansion of the railway networks,enhancing the efficiency and safety of the comprehensive system has become a crucial issue in the advanced development of railway *** light of the prevailing application of artificial intelligence technologies within railway systems,this study leverages large model technology characterized by robust learning capabilities,efficient associative abilities,and linkage analysis to propose an Artificial-intelligent(AI)-powered railway control and dispatching *** system is elaborately designed with four core functions,including global optimum unattended dispatching,synergetic transportation in multiple modes,high-speed automatic control,and precise maintenance decision and *** deployment pathway and essential tasks of the system are further delineated,alongside the challenges and obstacles *** AI-powered system promises a significant enhancement in the operational efficiency and safety of the composite railway system,ensuring a more effective alignment between transportation services and passenger demands.

关键词： High-speed railway Multi-mode railway system Artificial intelligence Large-scale mode,system framework Safety and efficiency improvement