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Constitutive model of viscoelastic dynamic damage for the material of gas obturator in modular-charge howitzer

Defence technology（防务技术） 2024年第9期39卷 203-216页

作者： Zhonggang Li Longmiao Chen Yifan Li Yufeng Jia Quan Zhang School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Technology Center Shanxi North Machine-building Co.Ltd.Taiyuan 030009China Research and Development Department Kelong New Material Technology Co.Ltd.Xianyang 712000China

In order to investigate the mechanical response behavior of the gas obturator of the breech mechanism,made of polychloroprene rubber(PCR), uniaxial compression experiments were carried out by using a universal testing machine and a split Hopkinson pressure bar(SHPB), obtaining stress-strain responses at different temperatures and strain rates. The results revealed that, in comparison to other polymers, the gas obturator material exhibited inconspicuous strain softening and hardening effects;meanwhile, the mechanical response was more affected by the strain rate than by temperature. Subsequently, a succinct viscoelastic damage constitutive model was developed based on the ZWT model, including ten undetermined parameters, formulated with incorporating three parallel components to capture the viscoelastic response at high strain rate and further enhanced by integrating a three-parameter Weibull function to describe the damage. Compared to the ZWT model, the modified model could effectively describe the mechanical response behavior of the gas obturator material at high strain rates. This research laid a theoretical foundation for further investigation into the influence of chamber sealing issues on artillery firing.

关键词： Breech mechanism Gas obturator Polychloroprene rubber Constitutive model Strain rate Damage

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Rumor Governance Under Uncertain Conditions: An Evolutionary Game Theory Analysis

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Annals of Data Science 2025年第3期12卷 1073-1111页

作者： Dong, Xuefan Tang, Lei College of Economics and Management Beijing University of Technology Beijing100124 China Research Base of Beijing Modern Manufacturing Development Beijing University of Technology Beijing100124 China

In the rapidly evolving landscape of online information dissemination, managing rumors has become an imperative challenge for governments worldwide. This study employs a tripartite evolutionary game model to examine the behavior evolution of the government, online media, and netizens in the process of rumor propagation under uncertain conditions. The innovation of the model lies in considering the probability of successful rumor detection under government regulation, the uncertainty of rumor dissemination by online media and netizens, and introducing a dynamic government penalty mechanism. Through simulation and analysis, we identify the evolutionarily stable strategies of each participant under different scenarios and provide specific governance strategies for each party involved. The results reveal that appropriate government penalties, proactive regulation by online media, and rational choices by netizens can effectively curb rumor spreading. In uncertain environments, adopting flexible policies and dynamic adjustment mechanisms is crucial for effective rumor governance. The results reveal that appropriate government penalties, proactive regulation by online media, and rational choices by netizens can effectively curb rumor spreading. In uncertain environments, adopting flexible policies and dynamic adjustment mechanisms is crucial for effective rumor governance. This study not only enriches the application of evolutionary game theory but also offers practical strategic recommendations for policymakers to address the challenges of rumor propagation. © The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature 2025.

关键词： Information dissemination

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Effect of Operating Parameters on the Real-Time Torque Distribution of a Plug-In Electric Hybrid Vehicle

SAE International journal of Sustainable Transportation, Ene...

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SAE International journal of Sustainable Transportation, Energy, Environment, and Policy 2023年第2期4卷

作者： Zhang, Yan Yuan, Xiayi Chongqing University of Technology China Automotive Research & Development Center Guangzhou Automobile Group Co. Ltd China

This article presented a real-time torque distribution strategy for a single-shaft, plug-in hybrid electric vehicle (PHEV) and investigated the effect of multiple operating parameters by using three working conditions, namely, steady operating conditions, acceleration operating conditions, and brake operating conditions. The corresponding experiments were performed according to the earlier discussed three working conditions. The main conclusions of this study are given as follows: (1) Under steady operating conditions, the engine no longer offers torque to the motor for charging when the pedal degree is higher than 60%. (2) Under acceleration conditions, the engine startup is sensitive to the state of charge (SOC) decrement, maximum of 1%, and this decrement increases with an increase in the initial SOC. (3) Under brake operating conditions, the initial SOC may have a significant influence on the variation stability of motor torque, especially when the braking intensity is less than 0.1. © 2023 SAE International. All rights reserved.

关键词： Plug-in hybrid vehicles

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Command filtered integrated estimation guidance and control for strapdown missiles with circular field of view

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Defence technology（防务技术） 2024年第5期35卷 211-221页

作者： Wei Wang Jiaqi Liu Shiyao Lin Baokui Geng Zhongjiao Shi School of Aerospace Engineering Beijing Institute of TechnologyBeijing 10081China China Research and Development Academy of Machinery Equipment Beijing 100089China Northwest Industries Group CO. Ltd.Xi'an 710043China

In this paper,an integrated estimation guidance and control(IEGC)system is designed based on the command filtered backstepping approach for circular field-of-view(FOV)strapdown *** threedimensional integrated estimation guidance and control nonlinear model with limited actuator deflection angle is established considering the seeker's FOV *** boundary time-varying integral barrier Lyapunov function(IBLF)is employed in backstepping design to constrain the body line-of-sight(BLOS)in IEGC system to fit a circular ***,the nonlinear adaptive controller is designed to estimate the changing aerodynamic *** generalized extended state observer(GESO)is designed to estimate the acceleration of the maneuvering targets and the unmatched time-varying disturbances for improving tracking ***,the command filters are used to solve the"differential expansion"problem during the backstepping *** Lyapunov theory is used to prove the stability of the overall closed-loop IEGC ***,the simulation results validate the integrated system's effectiveness,achieving high accuracy strikes against maneuvering targets.

关键词： Integrated estimation guidance and control Circular field-of-view Time-varying integral barrier Lyapunov function Command filtered backstepping control Nonlinear adaptive control Extended state observer

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research on flight operation risk probability assessment based on pilot competency

Research on flight operation risk probability assessment bas...

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2024 International Conference on Computer Application and Information Security, ICCAIS 2024

作者： Tian, Xianhui Liu, Kun Qiao, Dongxiao Xu, Yubin Wang, Xuhui Jin, Qinfang Research and Development Center China Academy of Civil Aviation Science and Technology Beijing100000 China

ISBN: (纸本)9781510689312

As an important part of modern transportation, the safety and reliability of air transport are directly related to the safety of passengers and crew. Many scholars have conducted extensive and in-depth research on flight risk assessment, but the competency data of flight crew has not been considered in the research. As the core of flight operation, the competency level of the flight crew directly threatens flight risk. Based on flight crew competency data and Fault Tree Analysis (FTA), this paper studies the probability assessment method of flight operation risk, forms a probability model of unsafe flight operation events, and carries out application analysis of the model through practical cases. This study provides a new way for airlines to estimate flight risk before flight departure, which can accurately estimate and control flight risk probability based on pilot competency data. © The Authors.

关键词： Risk assessment

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Microstructural Evolution during Tensile Deformation in TRC-ZA21 Magnesium Alloy with Different Loading Directions and Strain Rates

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Acta Metallurgica Sinica(English Letters) 2023年第2期36卷 192-214页

作者： Yun Zhang Chen Jiang Shaoheng Sun Wei Xu Quan Yang Yongjun Zhang Shiwei Tian Xiaoge Duan Zhe Xu Haitao Jiang Institute of Engineering Technology University of Science and Technology BeijingBeijing100083China China Electric Power Research Institute Beijing100055China Shunde Graduate School of University of Science and Technology Beijing Foshan528399China China Ship Research and Development Academy Beijing100081China

The variation of texture characteristics and activation of deformation mechanism in magnesium alloys can be achieved by addition of RE and Ca elements and subsequently affect the microstructure evolution during deformation *** this manuscript,the effects of loading direction and strain rate on mechanical properties,microstructural characteristics,texture evolution and deformation mechanism in TRC-ZA21 magnesium alloy sheet were ***,orientation dependence and strain rate sensitivity of deformation mechanism were also *** results showed that evident difference in mechanical properties in TRC-ZA21 alloy exhibited by the changes in loading direction and strain *** variations in grain orientation and basal texture characteristic were attributed to the grain rotation behavior during the plastic deformation,dominated by deformation *** slip,extension twinning and prismatic slip played different contributions to plastic deformation behavior and presented orientation dependence and strain rate *** activities of prismatic slip and extension twinning both enhance with increasing strain *** phenomenon of weakened effect of twinning and promoted role of prismatic slip was presented to coordinate strain compatibility during plastic deformation.

关键词： Magnesium alloys Mechanical property Orientation behavior Deformation mechanism Microstructural evolution

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Finite Elements modelling and assessment of ceramic rollers with edge cracks

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Procedia Structural Integrity 2024年 57卷 236-249页

作者： Yuri Kadin Charlotte Vieillard Jeroen Wensing Anand Theerthan SKF Research & Technology Development Houten The Netherlands

To ensure reliability of hybrid cylindrical roller bearings each ceramic roller is inspected, and scrapped if a surface imperfection above the critical size is detected. This inspection aims to reduce the potential root cause of Rolling Contact Fatigue (RCF) which can occur during operation, shortening the bearing life. The rejection criterion is based on experimental and theoretical knowledge, which for the last decade was developed in SKF for the material imperfections mainly located on the rolling element raceway. These imperfections are subjected to high contact pressure and therefore are considered as the primary root cause of RCF failure. Regarding rollers, however, imperfections can be present beyond the raceway, i.e. at the roller chamfer where the lower risk of RCF is expected, because the edge imperfections are typically out of the rolling contact zone. Nevertheless, the risk associated with these features should be assessed too, chiefly because the size of edge imperfections can be rather large. In our previous study, the imperfection termed as a Missing Material was studied, combining the semi-analytical tool for the contact mechanics and the Finite Elements (FE) method for the stress analysis. In the current work, another imperfection type is considered, and this is a surface crack located at the chamfer of ceramic roller. The RCF analysis is based on the semi-analytical evaluation of the rolling contact pressure (between a ceramic roller and a steel inner ring), and computational fracture mechanics for the estimation of fatigue crack propagation.

关键词： Si3N4 Ceramic rollers Hybrid bearing Fracture mechanics Rolling contact fatigue Finite Elements Material imperfections

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High Torque Capability Non-Permanent Magnet Hybrid Excited Switched Reluctance Motor for Electric Vehicle Application

High Torque Capability Non-Permanent Magnet Hybrid Excited S...

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2023 IEEE Energy Conversion Congress and Exposition, ECCE 2023

作者： Abhijith, Vijina Hossain, M.J. Lei, Gang Sreelekha, Premlal Ajikumar Kadam, Sandeep B University of Technology Sydney School of Electrical and Data Engineering Sydney Australia Entuple e Mobility Research and Development Bangalore India TechEmbers Research and Development Kerala India

ISBN: (纸本)9798350316445

Switched reluctance motors (SRMs) have become more prevalent in electric traction motors because they operate at high speeds, have optimum control, and can improve electrically driven performance with multiple phases overlapping. This can be attributed to their maximum torque per ampere and power density. The design and development of specialized electrical machines, like SRMs, have proliferated in recent years as an alternative to DC series and permanent magnet-based (PM) motors. This paper presents the design consideration and the performance evaluation of a hybrid excited non-permanent magnet assisted switched reluctance motor for electric vehicles (EV) applications. The hybrid excitation of switched reluctance motors (HESRM) is attracting considerable demand in the EV market due to its high torque performance. However, this method is currently incorporated with PM-assisted excitation to enhance the performance of SRMs. This newly designed hybrid excitation method enhances torque performance without using rare earth elements by injecting direct current (DC) through the designated auxiliary poles. The novel machine's static characteristics and dynamic performance are simulated and compared with the conventional SRM drives of the same ratings. Consequently, two motor prototypes are redesigned, and the concept is validated through experimental analysis. In all speed ranges, the proposed topologies provide significantly greater electromagnetic torque than the conventional ones. Because of its fault tolerance, multiple control topologies and redundancy were attained, thus making this machine well-suited for EV applications. © 2023 IEEE.

关键词： electric vehicle hybrid excitation of switched permanent magnet reluctance motor switched reluctance motor

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research on the performance of harmony search with local search algorithms for solving flexible job-shop scheduling problem

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Journal of Intelligent and Fuzzy Systems 2025年第3期48卷 291-304页

作者： Li, Jia Xue, Shuaihao Li, Minghui Shi, Xiaoqiu School of Manufacturing Science and Engineering Southwest University of Science and Technology Mianyang China State Key Laboratory of Intelligent Manufacturing Equipment and Technology School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan China Low Speed Aerodynamics Institute China Aerodynamics Research and Development Center Sichuan Mianyang China Key Laboratory of Icing and Anti/De-icing China Aerodynamics Research and Development Center Sichuan Mianyang China Mianyang Science and Technology City Intelligent Manufacturing Industry Technology Innovation Institute Sichuan Mianyang China

Combining the harmony search algorithm (HS) with the local search algorithm (LS) can prevent the HS from falling into a local optimum. However, how LS affects the performance of HS has not yet been studied systematically. Therefore, in this paper, it is first proposed to combine four frequently used LS with HS to obtain several search algorithms (HSLSs). Then, by taking the flexible job-shop scheduling problem (FJSP) as an example and considering decoding times, study how the parameters of HSLSs affect their performance, where the performance is evaluated by the difference rate based on the decoding times. The simulation results mainly show that (I) as the harmony memory size (HMS) gradually increases, the performance of HSLSs first increases rapidly and then tends to remain unchanged, and HMS is not the larger the better;(II) as harmony memory considering rate increases, the performance continues to improve, while the performance of pitch adjusting rate on HSLSs goes to the opposite;Finally, more benchmark instances are also used to verify the effectiveness of the proposed algorithms. The results of this paper have a certain guiding significance on how to choose LS and other parameters to improve HS for solving FJSP. © 2025 – IOS Press. All rights reserved.

关键词： Scheduling algorithms

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Geochemical characteristics of produced fluids from CBM wells and their indicative significance for gas accumulation in Daning-Jixian block,Ordos Basin

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Frontiers of Earth Science 2023年第3期17卷 661-678页

作者： Taotao YAN Chao YANG Shuai ZHENG Yadong BAI Wei CHEN Yanfei LIU Wenguang TIAN Shasha SUN Shangwen JIN Jiahang WANG Zhenxing LIU Huifang YAO College of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Coal Reservoir Laboratory of National Engineering Research Center of CBM Development&Utilization China University of GeosciencesBeijing 100083China China Coal Geology Group Co. LtdBeijing 100043China Research Institute of Petroleum Exploration and Development(Northwest) PetroChinaLanzhou 730000China Beijing Furuibao Energy Technology Company Beijing 100176China PetroChina Research Institute of Petroleum Exploration and Development Beijing 100083China Engineering Institute of SINOPEC Shanghai Offshore Oil&Gas Company Shanghai 200120China Exploration and Development Research Institute of PetroChina Huabei Oilfield Company PetroChinaRenqiu 062552China

The Daning-Jixian block,the eastern edge of the Ordos Basin,is one of the most potential areas for CO_(2)geological storage,enhanced coalbed methane recovery(ECBM)exploration and production in China in recent *** ionic composition and total dissolved solids(TDS)of the produced water,coal organic matter maturity,molecular composition and carbon isotope characteristics of the produced gas were utilized to analyze the hydrogeological condition,CBM generation and migration characteristics in this *** CBM enrichment patterns and the geological impacts on gas well production characteristics were *** optimal area for CBM development and CO_(2)geological storage in the study area were also *** by the Xueguan reverse fault zone,the hydraulic unit in this area can be divided into two parts(i.e.,the recharge-runoff zone in the east and the weak runoff-stagnation zone in the west).The thermogenic gas is dominating CBM genesis in this *** biogenic gas replenishment is only distributed in the eastern margin area,where theδ13C1 value is less than the thermal simulation results as an influence of hydrodynamic ***,two models of CBM formation and accumulation were proposed,1)thermogenic CBM migrated by hydrodynamic and resorbed for preservation at impermeable fault boundaries;2)thermogenic CBM trapped by fault and accumulated by hydrodynamic in slope *** gas production performance,generally increased from east to west,is mainly dominated by hydrogeological ***,the west side of the fault zone is the enrichment and high-yield area for ECBM development and CO_(2)geological storage in the study area.

关键词： produced water and gas gas accumulation geochemical parameter CBM production CO_(2)geological storage Daning-Jixian block

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