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A generalized nonlinear three-dimensional Hoek‒Brown failure criterion

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3149-3164页

作者： Jiaxin Wang Shunchuan Wu Haiyong Cheng Junlong Sun xiaolong Wang Yaxi Shen Faculty of Land Resource Engineering Kunming University of Science and TechnologyKunming650093China Key Laboratory of Geohazard Forecast and Geoecological Restoration in Plateau Mountainous Area Ministry of Natural ResourcesKunming650093China Yunnan Key Laboratory of Geohazard Forecast and Geoecological Restoration in Plateau Mountainous Area Kunming650093China

To understand the strengths of rocks under complex stress states,a generalized nonlinear threedimensional(3D)Hoek‒Brown failure(NGHB)criterion was proposed in this *** criterion shares the same parameters with the generalized HB(GHB)criterion and inherits the parameter advantages of *** new parameters,b,and n,were introduced into the NGHB criterion that primarily controls the deviatoric plane shape of the NGHB criterion under triaxial tension and compression,*** NGHB criterion can consider the influence of intermediate principal stress(IPS),where the deviatoric plane shape satisfies the smoothness requirements,while the HB criterion *** criterion can degenerate into the two modified 3D HB criteria,the Priest criterion under triaxial compression condition and the HB criterion under triaxial compression and tension *** criterion was verified using true triaxial test data for different parameters,six types of rocks,and two kinds of in situ rock *** comparison,three existing 3D HB criteria were selected for performance comparison *** result showed that the NGHB criterion gave better prediction performance than other *** prediction errors of the strength of six types of rocks and two kinds of in situ rock masses were in the range of 2.0724%-3.5091%and 1.0144%-3.2321%,*** proposed criterion lays a preliminary theoretical foundation for prediction of engineering rock mass strength under complex in situ stress conditions.

关键词： Rock mechanics HoekeBrown criterion Failure criterion Intermediate principal stress True triaxial test Smoothness and convexity

A Deformable Network with Attention Mechanism for Retinal Vessel Segmentation

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Journal of Beijing Institute of Technology 2024年第3期33卷 186-193页

作者： xiaolong Zhu Wenjian Li Weihang Zhang Dongwei Li Huiqi Li School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

The intensive application of deep learning in medical image processing has facilitated the advancement of automatic retinal vessel segmentation *** overcome the limitation that traditional U-shaped vessel segmentation networks fail to extract features in fundus image sufficiently,we propose a novel network(DSeU-net)based on deformable convolution and squeeze excitation residual *** deformable convolution is utilized to dynamically adjust the receptive field for the feature extraction of retinal *** the squeeze excitation residual module is used to scale the weights of the low-level features so that the network learns the complex relationships of the different feature layers *** validate the DSeU-net on three public retinal vessel segmentation datasets including DRIVE,CHASEDB1,and STARE,and the experimental results demonstrate the satisfactory segmentation performance of the network.

关键词： retinal vessel segmentation deformable convolution attention mechanism deep learning

Scale effect removal and range migration correction for hypersonic target coherent detection

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Journal of Systems Engineering and Electronics 2024年第1期35卷 14-23页

作者： WU Shang SUN Zhi JIANG Xingtao ZHANG Haonan DENG Jiangyun LI xiaolong CUI Guolong School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

The detection of hypersonic targets usually confronts range migration(RM)issue before coherent integration(CI).The traditional methods aiming at correcting RM to obtain CI mainly considers the narrow-band radar ***,with the increasing requirement of far-range detection,the time bandwidth product,which is corresponding to radar’s mean power,should be promoted in actual ***,the echo signal generates the scale effect(SE)at large time bandwidth product situation,influencing the intra and inter pulse integration *** eliminate SE and correct RM,this paper proposes an effective algorithm,i.e.,scaled location rotation transform(ScLRT).The ScLRT can remove SE to obtain the matching pulse compression(PC)as well as correct RM to complete CI via the location rotation transform,being implemented by seeking the actual rotation *** to the traditional coherent detection algorithms,Sc LRT can address the SE problem to achieve better detection/estimation *** last,this paper gives several simulations to assess the viability of ScLRT.

关键词： hypersonic target detection coherent integration(CI) scale effect(SE)removal range migration(RM)correction scaled location rotation transform(ScLRT)

Safe Efficient Policy Optimization Algorithm for Unsignalized Intersection Navigation

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IEEE/CAA Journal of Automatica Sinica 2024年第9期11卷 2011-2026页

作者： xiaolong Chen Biao Xu Manjiang Hu Yougang Bian Yang Li Xin Xu State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body the College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body the College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082 Wuxi Intelligent Control Research Institute(WICRI)of Hunan University Wuxi 214115China College of Intelligence Science and Technology Institute of Unmanned SystemsNational University of Defense TechnologyChangsha 410073China

Unsignalized intersections pose a challenge for autonomous vehicles that must decide how to navigate them safely and *** paper proposes a reinforcement learning(RL)method for autonomous vehicles to navigate unsignalized intersections safely and *** method uses a semantic scene representation to handle variable numbers of vehicles and a universal reward function to facilitate stable learning.A collision risk function is designed to penalize unsafe actions and guide the agent to avoid them.A scalable policy optimization algorithm is introduced to improve data efficiency and safety for vehicle learning at *** algorithm employs experience replay to overcome the on-policy limitation of proximal policy optimization and incorporates the collision risk constraint into the policy optimization *** proposed safe RL algorithm can balance the trade-off between vehicle traffic safety and policy learning *** intersection scenarios with different traffic situations are used to test the algorithm and demonstrate its high success rates and low collision rates under different traffic *** algorithm shows the potential of RL for enhancing the safety and reliability of autonomous driving systems at unsignalized intersections.

关键词： Autonomous driving decision-making reinforcement learning(RL) unsignalized intersection

Yanggan Jiangmei Formula alleviates hepatic inflammation and lipid accumulation in non-alcoholic steatohepatitis by inhibiting the NF-κB/NLRP3 signaling pathway

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Chinese Journal of Natural Medicines 2024年第3期22卷 224-234页

作者： WU Yuanyuan ZHOU Jingwen ZUO Xinchen KUANG Yufeng SUN Lixia ZHANG xiaolong The First Clinical Medical College Nanjing University of Chinese MedicineNanjing 210023China The Affiliated Hospital of Nanjing University of Chinese Medicine Jiangsu Province Hospital of Chinese MedicineNanjing 210029China

The role of NF-κB and the NLRP3 inflammasome in the chronic inflammatory microenvironment of non-alcoholic steatohepatitis(NASH)has been posited as *** Yanggan Jiangmei Formula(YGJMF)has shown promise in ameliorating hepatic steatosis in NASH patients,yet its pharmacological mechanisms remain largely *** study was conducted to investigate the efficacy of YGJMF in NASH and to elucidate its pharmacological *** simulate NASH both in vivo and in vitro,high-fat-diet(HFD)rats and HepG2 cells stimulated with free fatty acids(FFAs)were *** severity of liver injury and lipid deposition was assessed using serum indicators,histopathological staining,micro-magnetic resonance imaging(MRI),and the liver-tomuscle signal intensity ratio(SIRL/M).Furthermore,a combination of enzyme-linked immunosorbent assay(ELISA),immunohistochemistry(IHC),immunofluorescence,real-time quantitative polymerase chain reaction(RT-qPCR),and Western blotting analyses was employed to investigate the NF-κB/NLRP3 signaling pathway and associated cytokine *** results from liver pathology,MRI assessments,and biochemical tests in rat models demonstrated YGJMF’s significant effectiveness in reducing liver damage and lipid ***,YGJMF markedly reduced hepatocyte inflammation by downregulating inflammatory cytokines in both liver tissue and ***,YGJMF was found to disrupt NF-κB activation,consequently inhibiting the assembly of the NLRP3 inflammasome in both the in vitro and in vivo *** preliminary findings of this study suggest that YGJMF may alleviate hepatic steatosis and inhibit the NF-κB/NLRP3 signaling pathway,thereby exerting anti-inflammatory effects in NASH.

关键词： Non-alcoholic steatohepatitis Nuclear factor kappa B NLRP3 inflammasome Yanggan Jiangmei Formula

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触发器在实现数据库安全方面的新应用

计算机工程 2005年第19期31卷 157-159页

作者：康效龙张玉清田玉敏西安电子科技大学计算机科学与工程学院西安710071 中国科学院研究生院国家计算机网络入侵防范中心北京100039

针对目前大量利用数据库漏洞提升用户权限后的恶意篡改攻击,设计并实现了一种新的触发器应用,基于安全事件发生前或发生过程中构建了一层用户自定义的访问控制功能,提高了数据库的安全性,并在一定程度上,改变了目前数据库保护中主要依... 详细信息

针对目前大量利用数据库漏洞提升用户权限后的恶意篡改攻击,设计并实现了一种新的触发器应用,基于安全事件发生前或发生过程中构建了一层用户自定义的访问控制功能,提高了数据库的安全性,并在一定程度上,改变了目前数据库保护中主要依赖于事后恢复的局面。

关键词：触发器数据库安全访问控制

Survey on digital twins for Internet of Vehicles:Fundamentals,challenges,and opportunities

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Digital Communications and Networks 2024年第2期10卷 237-247页

作者： Jiajie Guo Muhammad Bilal Yuying Qiu Cheng Qian xiaolong Xu Kim-Kwang Raymond Choo School of Computer and Software Nanjing University of Information Science and TechnologyNanjing210044China Department of Computer Engineering Hankuk University of Foreign StudiesGyeonggi-do17035South Korea Jiangsu Hydraulic Research Institute Nanjing210044China Department of Information Systems and Cyber Security University of Texas at San AntonioSan AntonioTX78249-0631USA

As autonomous vehicles and the other supporting infrastructures(e.g.,smart cities and intelligent transportation systems)become more commonplace,the Internet of Vehicles(IoV)is getting increasingly *** have been attempts to utilize Digital Twins(DTs)to facilitate the design,evaluation,and deployment of IoV-based systems,for example by supporting high-fidelity modeling,real-time monitoring,and advanced predictive ***,the literature review undertaken in this paper suggests that integrating DTs into IoV-based system design and deployment remains an understudied *** addition,this paper explains how DTs can benefit IoV system designers and implementers,as well as describes several challenges and opportunities for future researchers.

关键词： Internet of vehicles Digital twin Simulation Traffic systems

Force Compensation Control for Electro-Hydraulic Servo System with Pump-Valve Compound Drive via QFT-DTOC

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 228-246页

作者： Kaixian Ba Yuan Wang xiaolong He Chunyu Wang Bin Yu Yaliang Liu Xiangdong Kong Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Qinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China National Engineering Research Center for Local Joint of Advanced Manufacturing Technology and Equipment Yanshan UniversityQinhuangdao 066004China

Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ***,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy *** contrast,pump control systems offer a high ***,their response ability is *** fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of ***,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first *** addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC *** method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the ***,experimental verification is performed using the PCDS performance test *** experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the *** relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.

关键词： Legged robot Pump-valve compound drive system(PCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)

Research on Scheduling Strategy of Flexible Interconnection Distribution Network Considering Distributed Photovoltaic and Hydrogen Energy Storage

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Energy Engineering 2024年第5期121卷 1263-1289页

作者： Yang Li Jianjun Zhao xiaolong Yang He Wang Yuyan Wang College of Electrical Engineering Northeast Electric Power UniversityJilin132011China Smart Distribution Network Center State Grid Jibei Electric Power Co.Ltd.Qinhuangdao066000China

Distributed photovoltaic(PV)is one of the important power sources for building a new power system with new energy as the main *** rapid development of distributed PV has brought new challenges to the operation of distribution *** order to improve the absorption ability of large-scale distributed PV access to the distribution network,the AC/DC hybrid distribution network is constructed based on flexible interconnection technology,and a coordinated scheduling strategy model of hydrogen energy storage(HS)and distributed PV is ***,the mathematical model of distributed PV and HS system is established,and a comprehensive energy storage system combining seasonal hydrogen energy storage(SHS)and battery(BT)is ***,a flexible interconnected distribution network scheduling optimization model is established to minimize the total active power loss,voltage deviation and system operating ***,simulation analysis is carried out on the improved IEEE33 node,the NSGA-II algorithm is used to solve specific examples,and the optimal scheduling results of the comprehensive economy and power quality of the distribution network are *** with the method that does not consider HS and flexible interconnection technology,the network loss and voltage deviation of this method are lower,and the total system cost can be reduced by 3.55%,which verifies the effectiveness of the proposed method.

关键词： Seasonal hydrogen storage flexible interconnection AC/DC distribution network photovoltaic absorption scheduling strategy