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Deformation energy of tectonic coal under hydrostatic conditions:A new calculation model based on critical state theory

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International Journal of Mining science and Technology 2025年第1期35卷 87-100页

作者： Chenghao Wang Haisong Liu Yuanping Cheng Liang Wang Jingyu Jiang Artificial Intelligence Research Institute China University of Mining and TechnologyXuzhou 221116China National Engineering Research Center for Coal Gas Control China University of Mining and TechnologyXuzhou 221116China Intelligent Early Warning and Prevention Research Center for Coal Mine Disasters China University of Mining and TechnologyXuzhou 221116China School of Safety Engineering China University of Mining and TechnologyXuzhou 221116China

The deformation energy(Wd)of soil-like tectonic coal is crucial for investigating the mechanism of coal and gas *** coal has a significant nonlinear constitutive relationship,which makes traditional elastic-based models for computing *** by critical state soil mechanics,this study theoretically established a new calculation model of Wdsuitable for the coal with nonlinear deformation *** the new model,the relationship between energy and stress no longer follows the square law(observed in traditional linear elastic models)but exhibits a power function,with the theoretical value of the power exponent ranging between 1 and *** cyclic loading and unloading experiments were conducted on four groups of tectonic coal samples and one group of intact coal *** results indicated that the relationship between Wdand stress for both intact and tectonic coal follows a power *** exponents for intact and tectonic coal are close to 2 and 1,*** stress-strain curve of intact coal exhibits small deformation and linear characteristics,whereas the stress-strain curves of tectonic coal show large deformation and nonlinear *** study specifically investigates the role of coal viscosity in the cyclic loading/unloading *** downward bending in the unloading curves can be attributed to the time-dependent characteristics of coal,particularly its viscoelastic *** on experimental statistics,the calculation model of Wdwas further *** simplified model involves only one unknown parameter,which is the power exponent between Wdand *** measured Wdof the coal samples increases with the number of load *** phenomenon is attributed to coal's viscoelastic *** the same stress,the Wdof tectonic coal is an order of magnitude greater than that of intact *** calculation model of Wdproposed in this paper provides a new tool for studying the energy princip

关键词： Coal and gas outburst Tectonic coal Deformation energy Calculation model Critical state soil mechanics

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Synthesis of nitrogen-doped reduced graphene oxide/magnesium ferrite/polyaniline composite aerogel as a lightweight,broadband and efficient microwave absorber

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Journal of Materials science & Technology 2024年第8期175卷 115-124页

作者： Ruiwen Shu Lijuan Nie Ziwei Zhao Xunhong Yang School of Chemical Engineering State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal MinesAnhui University of Science and TechnologyHuainan 232001China Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining Anhui University of Science and TechnologyHuainan 232001China

The fabrication of graphene-based microwave absorbing materials with low density,small filling ratio,broad bandwidth and strong absorption remains a huge *** this work,nitrogen-doped reduced graphene oxide/magnesium ferrite/polyaniline(NRGO/MgFe_(2)O_(4)/PANI)composite aerogel was synthesized by a three-step method of solvothermal reaction,in situ chemical oxidation polymerization and hydrothermal *** results showed that the obtained aerogels had a unique three-dimensional(3D)porous network structure and low bulk density(11.1-13.0 mg cm^(−3)).It was worth noting that in the NRGO/MgFe_(2)O_(4)/PANI ternary composite aerogel,MgFe_(2)O_(4)coated with a thin PANI layer was anchored on the surface of NRGO ***,the NRGO/MgFe_(2)O_(4)/PANI ternary composite aerogel showed much better microwave absorbing capacity compared with pure NRGO aerogel and NRGO/MgFe_(2)O_(4)binary composite *** the filling ratio was as low as 11.5 wt.%,the obtained ternary composite aerogel exhibited the maximum effective absorption bandwidth of 7.0 GHz at a matching thickness of 2.1 mm,and the minimum reflection loss of-42.9 dB at a thickness of 3.57 ***,the prob-able microwave dissipation mechanism was also *** was believed that this study would pave the way for the construction of 3D graphene-based composites as lightweight,broadband and efficient microwave absorbents.

关键词： Graphene Composite aerogel Polyaniline Magnesium ferrite Microwave absorption

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Investigation on coal damage and fracture extension law of liquid nitrogen injection pre-cooling and fracturing under true triaxial stress

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International Journal of Mining science and Technology 2025年第2期35卷 213-229页

作者： Botao Li Haifei Lin Jianping Wei Hongtu Zhang Shugang Li Zongyong Wei Lei Qin Pei Wang Rongwei Luo Zeran Liu School of Safety Science and Engineering Henan Polytechnic UniversityJiaozuo 454003China State Key Laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic UniversityJiaozuo 454003China State Collaborative Innovation Center of Coal Work Safety and Clean-efficiency Utilization Henan Polytechnic UniversityJiaozuo 454003China College of Safety Science and Engineering Xi’an University of Science and TechnologyXi’an 710054China Key Laboratory of Shaanxi Province Universities of Gas Disaster Prevention and Control in Western Coal Mines Xi’an 710054China

To more accurately describe the coal damage and fracture evolution law during liquid nitrogen(LN_(2))fracturing under true triaxial stress,a thermal-hydraulic-mechanical-damage(THMD)coupling model for LN_(2) fracturing coal was developed,considering the coal heterogeneity and thermophysical parameters of *** accuracy and applicability of model were verified by comparing with LN_(2) injection pre-cooling and fracturing experimental *** effects of different pre-cooling times and horizontal stress ratios on coal damage evolution,permeability,temperature distribution,and fracture characteristics were *** results show that the permeability and damage of the coal increase exponentially,while the temperature decreases exponentially during the fracturing *** the pre-cooling time increases,the damage range of the coal expands,and the fracture propagation becomes more *** initiation pressure and rupture pressure decrease and tend to stabilize with longer precooling *** the horizontal stress ratio increases,fractures preferentially extend along the direction of maximum horizontal principal stress,leading to a significant decrease in both initiation and rupture *** a horizontal stress ratio of 3,the initiation pressure drops by 48.07%,and the rupture pressure decreases by 41.36%.The results provide a theoretical basis for optimizing LN_(2) fracturing techniques and improving coal seam modification.

关键词： Liquid nitrogen fracturing Thermal–hydraulic-mechanical-damage coupling Heterogeneous coal True triaxial stress Fracture morphology

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MACLSTM: A Weather Attributes Enabled Recurrent Approach to Appliance-Level Energy Consumption Forecasting

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Computers, Materials & Continua 2025年第2期82卷 2969-2984页

作者： Ruoxin Li Shaoxiong Wu Fengping Deng Zhongli Tian Hua Cai Xiang Li Xu Xu Qi Liu NARI-TECH Nanjing Control System Co. Ltd.Nanjing211106China School of Software Nanjing University of Information Science&TechnologyNanjing210044China Jiangsu Province Engineering Research Center of Advanced Computing and Intelligent Services Nanjing210044China

Studies to enhance the management of electrical energy have gained considerable momentum in recent years. The question of how much energy will be needed in households is a pressing issue as it allows the management plan of the available resources at the power grids and consumer levels. A non-intrusive inference process can be adopted to predict the amount of energy required by appliances. In this study, an inference process of appliance consumption based on temporal and environmental factors used as a soft sensor is proposed. First, a study of the correlation between the electrical and environmental variables is presented. Then, a resampling process is applied to the initial data set to generate three other subsets of data. All the subsets were evaluated to deduce the adequate granularity for the prediction of the energy demand. Then, a cloud-assisted deep neural network model is designed to forecast short-term energy consumption in a residential area while preserving user privacy. The solution is applied to the consumption data of four appliances elected from a set of real household power data. The experiment results show that the proposed framework is effective for estimating consumption with convincing accuracy.

关键词： Electrical load forecasting cloud computing smart grid weather attributes energy consumption time-series analysis

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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

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A Parameter Adaptive Model Predictive control for Virtual Coupling

A Parameter Adaptive Model Predictive Control for Virtual Co...

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International Conference on Artificial Intelligence and Autonomous Transportation, AIAT 2024

作者： Zhu, Yu Zhang, Yadong School of Information Science and Technology Southwest Jiaotong University Chengdu611765 China Sichuan Engineering Research Center of Train Operation Control Technology Chengdu611765 China

ISBN: (纸本)9789819639564

Virtual coupling technology is currently a focal point within the railway industry. Through vehicle-to-vehicle communication, virtual coupling allows trains to form a unified train unit, thereby reducing inter-train spacing and enhancing transportation efficiency. The complexity of tracking operations and the shorter spacing between virtual coupled trains place high demands on controller performance. This paper designs an adaptive model predictive control (MPC), enabling automatic adjustment of control parameters with the train's operation. Firstly, this paper establishes a train dynamics model based on an improved single-point mass model. Secondly, considering the characteristics of train tracking operations, this paper formulates rules for varying control parameters, thus designing an adaptive MPC. Finally, to validate the effectiveness of the method, simulations were conducted using three heterogeneous trains for virtual coupling target tracking. The results indicate that compared to fixed-parameter MPC, the method proposed in this paper improves computational efficiency by 5% and reduces inter-train spacing tracking error by 16%. The effectiveness of the proposed control approach has been demonstrated, providing a reference for further research on dynamic adjustment of control parameters in train operation processes. © Beijing Paike Culture Commu. Co., Ltd. 2025.

关键词： Self adjusting control systems

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State of Charge Estimation for Electric Vehicle Battery Using Support Vector Machines Technique 25

State of Charge Estimation for Electric Vehicle Battery Usin...

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25th International Middle East Power System Conference, MEPCON 2024

作者： Osman, Ali A. Hamad, Mostafa S. Abdel-Khalik, Ayman Samy Dessouky, Yasser G. Arab Academy for Science and Technology Research and Innovation Center Alamein Egypt Arab Academy for Science and Technology Electrical and Control Department Alexandria Egypt Faculty of Engineering Electrical Engineering Department Alexandria Egypt

ISBN: (纸本)9798350379648

State-of-charge (SOC) estimation is considered as the fundamental challenge for battery management system (BMS). the available SOC estimation methods face difficulty for accurate SOC estimation with different conditions such as (ambient temperature, the speed of wind or the humidity, etc). In this study, the training data and the testing data required in the estimation operation are collected using a real battery pack then followed by normalization. Then, lab experiment with MATLAB simulation applied to validate the results and get a powerful source of data generator. Then, the parameters in the support vector machine for regression model tuned to get the best estimated for SOC. Finally, simulation experiments have been done using python script to train the model and test a new data set. The results show the efficiency of using support vector machine for regression in estimating the battery SOC. © 2024 IEEE.

关键词： State of charge

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High strength and high work hardening rate in oxygen gradient Ti-15Mo alloy

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Journal of Materials science & Technology 2024年第31期198卷 56-62页

作者： Zhixin Wang Kai Yao Binkai Du Suyun He Xiaohua Min Shewei Xin Shijian Zheng Tianjin Key Laboratory of Materials Laminating Fabrication and Interface Control Technology School of Materials Science and EngineeringHebei University of TechnologyTianjin 300130China School of Materials Science and Engineering Dalian University of TechnologyDalian 116024China Northwest Institute for Non-Ferrous Metal Research Xi'an 710016China

The low work hardening is a prominent deficiency for high-strength titanium(Ti)*** gradient design of oxygen content was adopted to realize the coupling deformation of{332}twinning and dislocation slip in the Ti-15Mo ... 详细信息

The low work hardening is a prominent deficiency for high-strength titanium(Ti)*** gradient design of oxygen content was adopted to realize the coupling deformation of{332}<113>twinning and dislocation slip in the Ti-15Mo *** oxygen gradient alloy exhibited an optimal balance of yield/tensile strength(700 and 848 MPa)and elongation(25%),with remarkable work hardening *** dominated dislocation slip deformation and the solution strengthening of oxygen atoms in the oxygen-rich region resulted in a remarkable increase in yield *** successive formation of{332}<113>twins and piled-up geometrically necessary dislocations around the twin boundaries in the oxygen-free region induced remarkable back stress strengthening,maintaining the high work hardening rate,which resulted in a stable increase in *** twins and dislocations formed at the crack tips effectively hindered the cracking behavior,avoiding premature *** present study provides a novel idea for designing oxygen layer-distributed Ti alloys,which further improves the strength-ductility tradeoff.

关键词： Titanium alloys Oxygen gradient Work hardening Heterogeneous material Ductility

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Preparation of α-High Strength Gypsum from Flue Gas Desulfurization Gypsum Pretreated by Hydrothermal-aging Method

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Journal of Wuhan University of Technology(Materials science) 2024年第1期39卷 75-81页

作者：苏一鑫 GAO Lili 陈学青 LI Zhishui 李雲 CAO Jilin Engineering Research Center of Seawater Utilization Technology of Ministry of Education School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Heze Center for Disease Control and Prevention Heze 274010China Tianjin Bohua Yongli Chemical Industry Co. Ltd.Tianjin 300452China

The synthesis of α-calcium sulfate hemihydrate (α-CSH) from flue gas desulfurization (FGD)gypsum is a good way to realize the comprehensive utilization of FGD gypsum. To obtainα-CSH with the satisfactory performances, a facile hydrothermal-aging pretreatment process for FGD gypsum raw materials was proposed, where FGD gypsum was firstly hydrothermally converted to α-CSH whiskers, and α-CSH whiskers were further hydrated to synthesize CaSO4·2H2O (CSD) by aging under the regulation of N,N'-methylenebisacrylamide (MBA). The effects of aging time, MBA addition, aging temperature, and pH on the morphology of the synthesized CSD were investigated. The synthesized CSD crystals exhibit highly uniform prismatic morphology with the length of ca 100μm and the whiteness of 91.56%. The regulation mechanism of MBA was also illustrated. The synthesized CSD crystals with prismatic morphology were further used as raw materials to synthesize the short columnar α-CSH. The absolute dry compressive strength of paste prepared from the short columnar α-CSH is 40.85 MPa, which reaches α40 strength grade.

关键词： flue gas desulphurization gypsum α-calcium sulfate hemihydrate hydrothermal-aging method N,N'-methylenebisacrylamide prismatic CSD

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MTPA real-time tracking method based on AC signal Injection

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International Journal of Vehicle Autonomous Systems 2023年第2-4期16卷 161-179页

作者： Jin, Ningzhi Chen, Hongchao Wu, Zhiqiang Zhang, Long Jiang, Jiaxin Engineering Research Centre of Automotive Electronics Drive Control and System Integration Ministry of Education Harbin University of Science and Technology Heilongjiang Harbin China

In the actual control of Interior Permanent Magnet Synchronous Motor (IPMSM), the electrical parameters often fluctuate due to magnetic saturation and temperature change and therefore it is impossible to achieve an accurate control. Aiming at parameter changes, a new real-time tracking method for Maximum Torque Per Ampere (MTPA) trajectory of permanent magnet synchronous motor is proposed. The angle information corresponding to the MTPA current is extracted by introducing a new MTPA reference frame, infusing it with appropriate high-frequency AC signal components, analysing the internal relationship between the electromagnetic torque pulsation component and the current vector angle under the new MTPA reference frame, and then configuring reasonable cut-off frequencies of low-pass and band-pass filters. At the same time, compared with the traditional injection method, it is not necessary to inject high-frequency current angle into the vector angle and when the system is stable, it can be injected intermittently to reduce losses. Thus, accurate and efficient control can be achieved without parameter identification. The simulation results verify the feasibility and effectiveness of the proposed control algorithm. © 2022 Inderscience Enterprises Ltd.

关键词： Bandpass filters

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