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Development of Cueing Algorithm Based on “Closed-Loop” Control for Flight Simulator Motion System

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Wuhan University Journal of Natural Sciences 2019年第5期24卷 376-382页

作者： ZHU Daoyang DUAN Shaoli FANG Da College of Intelligent manufacturing Wuhan Technical College of Communications

The classical washout algorithm had fixed gains and manually constructed filters, so that it led to poor adaptability. Furthermore, it lost the sustained acceleration cues of high-and mid-frequency in cross-over(tilt-coordination) channel, and the acceleration of cross-over frequency was also limited by angular velocity limiter, so the false cues in flight simulation process were clearly perceived by pilots. The paper studied the characteristics of the classical washout algorithm and flight simulator motion platform, tried to redesign the source of cross-over acceleration channel and translation acceleration channel, and transferred the part of cross-over acceleration that was unsimulated sustained acceleration to translation acceleration channel. Comparisons were mainly made between classical washout algorithm and revised algorithm in a longitudinal/pitch direction. The evaluation was based on the implementation of human vestibular perception system. The results demonstrated that the revised algorithm could significantly reduce the phase lag, and improved the spikes tracking performance. Furthermore, sensory angular velocity and the error of sensory acceleration were strictly controlled within the threshold of human perception system, and the displacement was a little broader than the classical washout algorithm. Therefore, it was proved that the new algorithm could diminish the filters parameters and heighten the self-adaptability for the washout algorithm. In addition, the magnitude of false cues was remarkably reduced during flight simulator, and the workspace utilization of the motion platform was developed by "closed-loop" control system.

关键词： classical washout algorithm human vestibular system "closed-loop" control false cues

Unraveling structure evolution failure mechanism in MoS_(2)anode for improving lithium storage stability

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Journal of Materials Science & Technology 2022年第33期128卷 245-253页

作者： Guannan Zu Shiyu Xu Changhao Wang Hongyi Li Manchen Zhang Xiaoxing Ke Yuxiang Hu Ruzhi Wang Jinshu Wang Key Laboratory of Advanced Functional Materials of Education Ministry of China Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China Beijing Key Laboratory of Microstructure and Properties of Solids Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

2 H phase molybdenum disulfide(2 H-MoS_(2))possesses the two-dimensional layered structure and high theoretical capacity,presenting excellent lithiation-delithiation ***,the violent capacity decay within dozens of cycles still remains a great challenge due to lacking of in-depth failure ***,a novel decay-recovery-decay failure phenomenon upon long-term cycles is reported for the first time,which originates from the slow size change of Mo nanoparticles(NPs).Decay stages are triggered by many irregular-shaped Mo NPs with the increasing size up to~15 nm,leading to prominent pseudocapacitance failure and capacity *** recovery stages are attributed to the pulverization of coarse Mo NPs through surface sulfurization and accompanying *** overcome the instability issue,proper modifiers should be introduced to restrain the spontaneous growth of Mo NPs,such as aluminum oxide(Al_(2)O_(3)).The strong Mo-Al_(2)O_(3)bond gradually"drags"Al_(2)O_(3)fragments into the active material as the cycle continuously proceeds,resulting in the efficient refinement and the reversible conversion between Mo and MoS_(2).Therefore,the enhanced cycling stability and the capacity retention are successfully *** is expected to provide a new insight into the energy storage of transition metal chalcogenide anode materials in rechargeable batteries.

关键词： 2H-MoS_(2) Decay-recovery-decay Mo nanoparticles Al_(2)O_(3) Enhanced cycling stability

Local Stress Measurement in Thin Aluminum Plates based on Zero-Group-Velocity Lamb mode

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Chinese Journal of Mechanical Engineering 2023年第2期36卷 155-165页

作者： Weiming Xuan Maodan Yuan Xuanrong Ji Wenjin Xu Yan Chen Lvming Zeng State Key Laboratory of Precision Electronic manufacturing Technology and Equipment Guangdong University of TechnologyGuangzhou 510006China

The stress state is critical to the reliability of structures,but existing ultrasonic methods are challenging to measure local *** this paper,zero-group-velocity(ZGV)Lamb mode was proposed to measure the local stress field in thin aluminum *** Lamb wave’s dispersive characteristics under initial stress were analyzed based on the FloquetBloch theory with Murnaghan hyperelastic material *** obtained dispersion curves show that higher-order Lamb wave modes near the cut-off frequencies are sensitive to applied stress across the plate,indicating that the S1-ZGV mode has a rather high sensitivity to *** to conventional ultrasonic stress measurement,it is found that the frequency of the S1-ZGV mode changes near-linearly with the amplitude of applied *** experiments were conducted to illustrate the feasibility of local stress measurement in a thin aluminum plate based on the S1-ZGV *** and multiple localized stress fields were evaluated with the S1-ZGV method,and reconstructed results matched well with actual stress fields,proving that the ZGV Lamb wave method is a sensitive stress measurement technique in thin plates.

关键词： Stress field Zero-group-velocity mode Dispersion curves Acoustoelastic effect Lamb wave

Analysis on influencing factors of detecting chemical oxygen demand in water by ultraviolet absorption spectroscopy

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Optoelectronics Letters 2022年第12期18卷 749-754页

作者： ZHOU Kunpeng LIU Zhiyang CONG Menglong MAN Shanxin Intelligent manufacturing Technology Key Laboratory Intelligent Agricultural Machinery Equipment&Technology TeamCollege of EngineeringInner Mongolia Minzu UniversityTongliao028000China College of Information Engineering Jingzhou University(College of Engineering and Technology Yangtze University)Jingzhou434000China Alxa League Meteorological Bureau Alxa750300China

Taking the standard solution and actual water samples as the research object, this paper studies the influence of various environmental factors(temperature, alkalinity(pH), inorganic salt ions and salinity) on the detection of chemical oxygen demand(COD) in water by ultra-violet(UV) spectrometry, analyzes the influence mechanism, and draws relevant conclusions. The results show that the UV absorbance of the COD standard solution and the actual river water samples varies very little with temperature. The value of pH has certain impact on both the standard solution and the actual water samples, but the pH values of the affected experimental samples are in different ranges. The effects of nitrogen salt ions(NO_(2)^(-)and NO_(3)^(-)) on the UV absorption spectra can be eliminated by intercepting the UV spectrum interval less affected for modeling. The influence of salinity values below 35‰ on the UV absorption spectrum of water is mainly concentrated in the spectral band of 200—250 nm, and the influence above 250 nm is very little. This paper provides a preliminary analysis and discussion on the influence mechanism and laws of various environmental factors in the detection of water quality parameters by UV spectrometry, which provides an experimental basis for selecting the optimal test conditions when establishing the COD prediction model.

关键词： absorption chemical mechanism

A Discrete Multi‑Objective Artificial Bee Colony Algorithm for a Real‑World Electronic Device Testing Machine Allocation Problem

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Chinese Journal of Mechanical Engineering 2022年第6期35卷 136-150页

作者： Jin Xie Xinyu Li Liang Gao State Key Laboratory of Digital manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China

With the continuous development of science and technology,electronic devices have begun to enter all aspects of human life,becoming increasingly closely related to human *** have higher quality requirements for electronic *** device testing has gradually become an irreplaceable engineering process in modern manufacturing enterprises to guarantee the quality of products while preventing inferior products from entering the *** the large output of electronic devices,improving the testing efficiency while reducing the testing cost has become an urgent problem to be *** study investigates the electronic device testing machine allocation problem(EDTMAP),aiming to improve the production of electronic devices and reduce the scheduling distance among testing machines through reasonable machine ***,a mathematical model was formulated for the EDTMAP to maximize both production and the scheduling distance among testing ***,we developed a discrete multi-objective artificial bee colony(DMOABC)algorithm to solve EDTMAP.A crossover operator and local search operator were designed to improve the exploration and exploitation of the algorithm,*** experiments were conducted to evaluate the performance of the proposed *** experimental results demonstrate the superiority of the proposed algorithm compared with the non-dominated sorting genetic algorithm II(NSGA-II)and strength Pareto evolutionary algorithm 2(SPEA2).Finally,the mathematical model and DMOABC algorithm were applied to a real-world factory that tests radio-frequency *** results verify that our method can significantly improve production and reduce the scheduling distance among testing machines.

关键词： Electronic device Machine allocation Multi-objective optimization Artificial bee colony algorithm

A Fast Charging–Cooling Coupled Scheduling Method for a Liquid Cooling-Based Thermal Management System for Lithium-Ion Batteries

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Engineering 2021年第8期7卷 1165-1176页

作者： Siqi Chen Nengsheng Bao Akhil Garg Xiongbin Peng Liang Gao State Key Laboratory of Digital manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China Intelligent manufacturing Key Laboratory of Ministry of Education Shantou UniversityShantou 515063China

Efficient fast-charging technology is necessary for the extension of the driving range of electric ***,lithium-ion cells generate immense heat at high-current charging *** order to address this problem,an efficient fast charging–cooling scheduling method is urgently *** this study,a liquid cooling-based thermal management system equipped with mini-channels was designed for the fastcharging process of a lithium-ion battery module.A neural network-based regression model was proposed based on 81 sets of experimental data,which consisted of three sub-models and considered three outputs:maximum temperature,temperature standard deviation,and energy *** sub-model had a desirable testing accuracy(99.353%,97.332%,and 98.381%)after *** regression model was employed to predict all three outputs among a full dataset,which combined different charging current rates(0.5C,1C,1.5C,2C,and 2.5C(1C=5 A))at three different charging stages,and a range of coolant rates(0.0006,0.0012,and 0.0018 kg·s^(-1)).An optimal charging–cooling schedule was selected from the predicted dataset and was validated by the *** results indicated that the battery module’s state of charge value increased by 0.5 after 15 min,with an energy consumption lower than 0.02 *** maximum temperature and temperature standard deviation could be controlled within 33.35 and 0.8C,*** approach described herein can be used by the electric vehicles industry in real fast-charging ***,optimal fast charging-cooling schedule can be predicted based on the experimental data obtained,that in turn,can significantly improve the efficiency of the charging process design as well as control energy consumption during cooling.

关键词： Lithium-ion battery module Fast-charging Neural network regression Scheduling State of charge Energy consumption

Novel thin plate element theory based on a continuity re-relaxed technique

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Science China(Technological Sciences) 2010年第9期53卷 2450-2457页

作者： CUI XiangYang,LI GuangYao & ZHENG Gang State Key Laboratory of Advanced Design and manufacturing for Vehicle Body,Hunan University,Changsha 410082,China State Key Laboratory of Advanced Design and manufacturing for Vehicle Body Hunan University Changsha China

Thin plate problem has been receiving much interest due to its wide application in *** this paper,a novel thin plate element theory is proposed based on a continuity re-relaxed technique to avoid the high continuity requirement for thin plate formulation which needs the high computation *** problem is first discretized into a set of background cells with field nodes,and only deflection field is treated as the field *** top of the background cells,the integration domains are further *** curvatures over integration domains are restructured through the divergence theorem,and the continuity requirement of the trial deflection function for thin plate problems can be *** Galerkin weak form is then used to create the discretized system *** curvatures in the integration domains are constant,and the stiffness matrix of the system can be computed directly without numerical *** rotational essential boundary conditions are imposed in the process of curvature field *** numerical examples are computed using the RPIM approximation *** excellent results demonstrate the efficiency of the proposed method.

关键词： thin plate problem continuity re-relaxed curvature field restructured Galerkin weak form

Deciphering the critical effect of cathode-electrolyte interphase by revealing its dynamic evolution

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Journal of Energy Chemistry 2023年第6期81卷 192-199,I0006页

作者： Zhengfeng Zhang Changdong Qin Kuan Wang Xiao Han Jinhui Li Manling Sui Pengfei Yan Beijing Key Laboratory of Microstructure and Property of Solids Faculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China

Cathode electrolyte interphase(CEI)layer plays a crucial role in determining the electrochemical performance of lithium-ion *** by the sensitive nature of CEI and the lack of characterization techniques,its dynamic evolution during cycling,its formation mechanism,and its specific impact on battery performance are not yet fully ***,we systematically investigate the dynamic evolution of CEI layer and its critical effect on the cycling performance of LiCoO_(2)cathode by diverse characterization *** find that cycling voltage plays a key role in affecting CEI formation and evolution,and a critical potential(4.05 V ***)is identified,which acts as the switching potential between CEI deposition and *** show that CEI starts deposition in the discharge process when the potential is below 4.05 V,and CEI decomposition occurs when the potential is higher than 4.05 *** the battery is cycled below such a critical potential,a stable CEI layer is developed,which leads to superior cycling *** the battery is cycled above such a critical potential,a CEI-free cathode interface is observed,which also demonstrates good cycle ***,when the critical potential falls in the cycling voltage range,CEI deposition and decomposition are repeatedly switched on during cycling,leading to the dynamically unstable CEI *** unstable CEI layer causes continuous interfacial reaction and degradation,resulting in battery performance *** work deepens the understanding of the CEI formation and evolution mechanisms,and clarifies the critical effect of CEI layer on cycling performance,which provides new insights into stabilizing the electrode-electrolyte interface for high-performance rechargeable batteries.

关键词： LiCoO_(2) CEI Lithium-ion battery Electron microscopy XPS

Effect of Hot Isostatic Pressing on Fatigue Properties of Laser Melting Deposited AerMet100 Steel

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Journal of Iron and Steel Research International 2013年第11期20卷 79-84页

作者： CHENG Hao LIU Dong TANG Hai-bo ZHANG Shu-quan RAN Xian-zhe WANG Hua-ming Engineering Research Center of Ministry of Education on Laser Direct manufacturing for Large Metallic Components Beihang University

The ultra-high strength steel AerMetl00 was fabricated .by laser melting deposition （LMD） process. The effect of hot isostatic pressing （HIP） on high-cycle fatigue properties of the LMD AerMet100 steel was investigated, and the influence of defects on fatigue behavior was discussed. Results showed that the LMD AerMetl00 steel had fine directionally solidified cellular dendrite structure and coarse columnar prior austenite grains. Metallurgical de fects such as gas pore and lack-of-fusion porosity were produced during the laser deposition process. After HIP treat- ment, the number and size of metallurgical defects had remarkably decreased. Moreover, high-cycle fatigue proper ties of the alloys after HIP treatment were superior to the as-deposited alloys.

关键词： laser melting deposition hot isostatic pressing AerMetl00 steel high cycle fatigue metallurgical defect