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Defence Technology（防务技术） 2024年第2期32卷 1-22页

作者： Zengliang Han Mou Chen Haojie zhu Qingxian Wu School of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Unmanned autonomous helicopter(UAH)path planning problem is an important component of the UAH mission planning *** to reduce the influence of non-complete ground threat information on UAH path planning,a ground threat prediction-based path planning method is proposed based on artificial bee colony(ABC)algorithm by collaborative thinking ***,a dynamic threat distribution probability model is developed based on the characteristics of typical ground *** dynamic no-fly zone of the UAH is simulated and established by calculating the distribution probability of ground threats in real ***,a dynamic path planning method for UAH is designed in complex environment based on the real-time prediction of ground *** adding the collision warning mechanism to the path planning model,the flight path could be dynamically adjusted according to changing no-fly ***,a hybrid enhanced ABC algorithm is proposed based on collaborative thinking *** proposed algorithm applies the leader-member thinking mechanism to guide the direction of population evolution,and reduces the negative impact of local optimal solutions caused by collaborative learning update strategy,which makes the optimization performance of ABC algorithm more controllable and ***,simulation results verify the feasibility and effectiveness of the proposed ground threat prediction path planning method.

关键词： UAH Path planning Ground threat prediction Hybrid enhanced Collaborative thinking

Terminal attitude selection method of missile attack aircraft

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Chinese Journal of Aeronautics 2024年第2期37卷 385-400页

作者： Peng HOU Yang PEI Yuxue GE Mengjie zhu School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Research Department Shanghai Electro-Mechanical Engineering InstituteShanghai 201108China

The appropriate terminal attitude of missile is important to improve the damage effectiveness of fragmentation warhead against aircraft *** this paper,three missile terminal attitude selection methods are proposed to solve the problem of terminal attitude selection in different situations according to their respective evaluation *** MVE-based method uses the damage probability of each detonation point around the aircraft at a given attitude of missile to calculate the Mean Volume of Effectiveness(MVE)at the corresponding attitude,and then uses the MVE for different attitudes to select the terminal strike *** detonation position-based method addresses the case where the missile detonation position can be assessed in *** the effects of missile guidance errors and fuze activation position errors,Monte Carlo simulations are used to calculate the damage probability of aircraft with different strike attitudes,from which the terminal strike attitude is *** BP-ANN model-based method uses the constructed Back Propagation Artificial Neural Network(BP-ANN)model instead of simulation to calculate the evaluation indexes in the corresponding cases of MVE-based method and Detonation position-based method,which can improve the efficiency of attitude *** are conducted for different scenarios to verify the feasibility and effectiveness of the proposed method.

关键词： Aircraft vulnerability Attitude selection BP-ANN Damage probability Damage effectiveness

Wearable Leg Movement Monitoring System for High-Precision Real-Time Metabolic Energy Estimation and Motion Recognition

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Research 2024年第2期2023卷 417-429页

作者： Jinfeng Yuan Yuzhong Zhang Shiqiang Liu Rong zhu State Key Laboratory of Precision Measurement Technology and Instruments Department of Precision InstrumentTsinghua UniversityBeijing 100084China

Comprehensive and quantitative assessment of human physical activity in daily life is valuable for healthcare,especially for those who suffer from obesity and neurological disorders or are at high risk of *** wearable devices,e.g.,smartwatches,are insufficient and inaccurate for monitoring highly dynamic limb movements and assessing human ***,we report a new wearable leg movement monitoring system incorporating a custom-made motion sensor with machine learning algorithm to perceive human motion accurately and comprehensively during diverse walking and running *** system enables real-time multimodal perceptions of personal identity,motion state,locomotion speed,and energy expenditure for wearers.A general law of extracting real-time metabolic energy from leg movements is verified although individual gaits show *** addition,we propose a novel sensing configuration combining unilateral lower leg movement velocity with its angular rate to achieve high accuracy and good generalizability while simplifying the wearable *** performances in personal identification(accuracy of 98.7%)and motion-state recognition(accuracy of 93.7%)are *** wearable system also exhibites high-precision real-time estimations of locomotion speed(error of 3.04%to 9.68%)and metabolic energy(error of 4.18%to 14.71%)for new subjects across various time-varying *** wearable system allows reliable leg movement monitoring and quantitative assessment of bodily kinematic and kinetic behaviors during daily activities,as well as safe identity authentication by gait parameters,which would greatly facilitate smart life,personal healthcare,and rehabilitation training.

关键词： smart enable monitoring

Design method and experimental study of a cathode tool with an extremely high leveling ratio for electrochemical machining of blisk

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Chinese Journal of Aeronautics 2024年第4期37卷 593-608页

作者： Moqi SHEN Jia LIU Jingtao WANG Di zhu College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China

To obtain final parts with the desired dimensional accuracy and repeatability via electrochemical machining(ECM), the machining process must enter an ECM balanced state. However,for the ECM processing of blisk, a key component of aerospace engines, the surface of the blade blank often has an uneven allowance distribution due to the narrow passage of the cascade. It is difficult to remedy this issue in subsequent processing steps, which is necessary to ensure the dimensional accuracy and repeatability of the final blade profile. To solve this problem, electrolytic machining must be preceded by electrolytic shaping, which requires cathode tools with large leveling ratios to quickly homogenize the blank surface of the blade. In this study, to obtain a cathode tool with an extremely high leveling ratio, a design method based on the variation in the electrode gap in the non-equilibrium electrolytic state is proposed, and a dissolution model based on the nonequilibrium state is established. In this design method, the allowance on the blank to be machined is first divided into many discrete allowances with the normal direction. The initial machining clearance, feed rate, and total machining time are then calculated using classical ECM equilibrium state theory based on the maximum allowance. Meanwhile, the point coordinates of the cathode tool at maximum allowance can be determined. The non-equilibrium model can then be used to calculate the relative coordinate positions corresponding to the remaining discrete allowances. Finally, the entire cathode tool profile is designed. Simulations, fundamental experiments, and blisk unit workpiece experiments were carried out to validate the design approach. In the simulated processing of the plane workpiece, the leveling ratio of the cathode tool designed by the proposed method(0.77)was 83% higher than that of the cathode tool designed using the traditional method. The simulation results were confirmed by processing experiments. In t

关键词： Electrochemical machining(ECM) Non-equilibrium machining Large leveling ratios Cathode design Finite element simulation Blisk

Gas–solid reactor optimization based on EMMS-DPM simulation and machine learning

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Particuology 2024年第6期89卷 131-143页

作者： Haolei Zhang Aiqi zhu Ji Xu Wei Ge State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing 100190China

Design,scaling-up,and optimization of industrial reactors mainly depend on step-by-step experiments and engineering experience,which is usually time-consuming,high cost,and high *** numerical simulation can reproduce high resolution details of hydrodynamics,thermal transfer,and reaction process in reactors,it is still challenging for industrial reactors due to huge computational *** this study,by combining the numerical simulation and artificial intelligence(AI)technology of machine learning(ML),a method is proposed to efficiently predict and optimize the performance of industrial reactors.A gas–solid fluidization reactor for the methanol to olefins process is taken as an example.1500 cases under different conditions are simulated by the coarse-grain discrete particle method based on the Energy-Minimization Multi-Scale model,and thus,the reactor performance data set is *** develop an efficient reactor performance prediction model influenced by multiple factors,the ML method is established including the ensemble learning strategy and automatic hyperparameter optimization technique,which has better performance than the methods based on the artificial neural ***,the operating conditions for highest yield of ethylene and propylene or lowest pressure drop are searched with the particle swarm optimization algorithm due to its strength to solve non-linear optimization *** show that decreasing the methanol inflow rate and increasing the catalyst inventory can maximize the yield,while decreasing methanol the inflow rate and reducing the catalyst inventory can minimize the pressure *** two objectives are thus conflicting,and the practical operations need to be compromised under different circumstance.

关键词： Discrete particle method Artificial intelligence Machine learning Particle swarm optimization Industrial reactor optimization

High-efficiency crystalline white organic lightemitting diodes

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Light(Science & Applications) 2024年第4期13卷 747-759页

作者： Yijun Liu Feng zhu Yue Wang Donghang Yan State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China. School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China. State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun 130012China

Crystalline white organic light-emitting diodes(C-WOLEDs)are promising candidates for lighting and display *** is urgently necessary,however,to develop energy-saving and high-efficiency C-WOLEDs that have stable and powerful emission to meet commercial ***,we report a crystalline host matrix(CHM)with embedded nanoaggregates(NA)structure for developing high-performance C-WOLEDs by employing a thermally activated delayed fluorescence(TADF)material and orange phosphorescent dopants(Phos.-D).The CHM-TADFNA-D WOLED exhibit a remarkable EQE of 12.8%,which is the highest performance WOLEDs based on crystalline *** device has a quick formation of excitons and a well-designed energy transfer process,and possesses a fast ramping of luminance and current *** to recently reported high-performance WOLEDs based on amorphous material route,the C-WOLED achieves a low series-resistance Joule-heat loss ratio and an enhanced photon output,demonstrating its significant potential in developing the next-generation WOLEDs.

关键词： diodes dopant crystalline

Recent progresses in thermal treatment of β-Ga_(2)O_(3) single crystals and devices

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1659-1677页

作者： Yuchao Yan zhu Jin Hui Zhang Deren Yang State Key Laboratory of Silicon and Advanced Semiconductor Materials and School of Materials Science and Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Provincial Key Laboratory of Power Semiconductor Materials and Devices ZJU-Hangzhou Global Scientific and Technological Innovation CenterHangzhou 311200China

In recent years,ultra-wide bandgap β-Ga_(2)O_(3) has emerged as a fascinating semiconductor material due to its great potential in power and photoelectric *** semiconductor industrial,thermal treatment has been widely utilized as a convenient and effective approach for substrate property modulation and device ***,a thorough summary of β-Ga_(2)O_(3) substrates and devices behaviors after high-temperature treatment should be *** this review,we present the recent advances in modulating properties of β-Ga_(2)O_(3) substrates by thermal treatment,which include three major applications:(ⅰ)tuning surface electrical properties,(ⅱ)modifying surface morphology,and(ⅲ)oxidating ***,regulating electrical contacts and handling with radiation damage and ion implantation have also been discussed in device *** each category,universal annealing conditions were speculated to figure out the corresponding problems,and some unsolved questions were proposed *** review could construct a systematic thermal treatment strategy for various purposes and applications of β-Ga_(2)O_(3).

关键词： β-gallium oxide thermal treatment substrates devices

DEM investigation of strength and critical state behaviours of granular materials under true triaxial loadings

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Particuology 2024年第2期85卷 198-212页

作者： Minyi zhu Guobin Gong Jun Xia Stephen Wilkinson Department of Civil Engineering Xi'an Jiaotong-Liverpool UniversityChina Department of Civil Engineering and Industrial Design University of LiverpoolLiverpoolUK Faculty of Engineering and Information Sciences University of Wollongong in DubaiUnited Arab Emirates

This paper investigates the strength and critical state(CS)behaviours of granular materials via DEM simulations of true triaxial drained tests under three different loading modes including constant b(in-termediate stress ratio)tests with constantσ'1(major principal stress),constant p(mean pressure)and constantσ'3(minor principal stress)*** this end,a series of samples are generated with the same particle size distribution,and with the confining stresses ranging from 100 kPa to 900 *** CS is achieved for all *** the macroscopic behaviours and the microscopic behaviours are examined and compared considering different loading modes,confining stresses and intermediate stress ratios(b).The critical state lines(CSLs)are found to be unique and independent of the loading modes,but dependent on the b *** CSLs with b=0 and b=1 form the two boundaries of CSLs respectively beyond which CSLs under all other b tests cannot go *** different strength criteria are examined and compared in terms of both peak and CS *** Mohr-Coulomb strength criterion is found to be only suitable for axisymmetric loading *** Lade-Duncan criterion is only suitable for describing peak strengths,which is dependent on the loading modes and confining *** Satake criterion and Matsuoka-Nakai criterion are the more appropriate strength criteria for describing CS failures,indicating that the CS values of both the Satake parameter and the Matsuoka-Nakai parameter describe an inherent property that characterizes the CS failure for a given type of *** CS mechanical coordination number is fitted by a curved line for a given b value,which is unique regardless of the loading *** peak and CS values of both major and minor principal fabric tensors decrease with increasing b values,while they increase with increasing b values for the intermediate principal fabric tensor.

关键词： Discrete element method Intermediate stress ratio Dilation Critical state Failure criterion

A Self-Adapting and Efficient Dandelion Algorithm and Its Application to Feature Selection for Credit Card Fraud Detection

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 377-390页

作者： Honghao zhu MengChu Zhou Yu Xie Aiiad Albeshri IEEE School of Computer and Information Engineering Bengbu UniversityBengbu 233030China School of Information and Electronic Engineering Zhejiang Gongshang UniversityHangzhou 310018China Helen and John C.Hartmann the Department of Electrical and Computer EngineeringNew Jersey Institute of TechnologyNewark NJ 07102 USA College of Information Engineering Shanghai Maritime UniversityShanghai 201306China Department of Computer Science King Abdulaziz UniversityJeddah 21481Saudi Arabia

A dandelion algorithm(DA) is a recently developed intelligent optimization algorithm for function optimization problems. Many of its parameters need to be set by experience in DA,which might not be appropriate for all optimization problems. A self-adapting and efficient dandelion algorithm is proposed in this work to lower the number of DA's parameters and simplify DA's structure. Only the normal sowing operator is retained;while the other operators are discarded. An adaptive seeding radius strategy is designed for the core dandelion. The results show that the proposed algorithm achieves better performance on the standard test functions with less time consumption than its competitive peers. In addition, the proposed algorithm is applied to feature selection for credit card fraud detection(CCFD), and the results indicate that it can obtain higher classification and detection performance than the-state-of-the-art methods.

关键词： Credit card fraud detection(CCFD) dandelion algorithm(DA) feature selection normal sowing operator

Feedback Mechanism-driven Mutation Reptile Search Algorithm for Optimizing Interpolation Developable Surfaces

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Journal of Bionic Engineering 2024年第1期21卷 527-571页

作者： Gang Hu Jiao Wang Xiaoni zhu Muhammad Abbas Department of Applied Mathematics Xi'an University of TechnologyXi'an 710054China School of Mechanical and Precision Instrument Engineering Xi'an University of TechnologyXi'an 710048China Department of Mathematics University of SargodhaSargodha 40100Pakistan

Curvature lines are special and important curves on *** is of great significance to construct developable surface interpolated on curvature lines in engineering *** this paper,the shape optimization of generalized cubic ball developable surface interpolated on the curvature line is studied by using the improved reptile search ***,based on the curvature line of generalized cubic ball curve with shape adjustable,this paper gives the construction method of SGC-Ball developable surface interpolated on the ***,the feedback mechanism,adaptive parameters and mutation strategy are introduced into the reptile search algorithm,and the Feedback mechanism-driven improved reptile search algorithm effectively improves the solving *** IEEE congress on evolutionary computation 2014,2017,2019 and four engineering design problems,the feedback mechanism-driven improved reptile search algorithm is compared with other representative methods,and the result indicates that the solution performance of the feedback mechanism-driven improved reptile search algorithm is *** last,taking the minimum energy as the evaluation index,the shape optimization model of SGC-Ball interpolation developable surface is *** developable surface with the minimum energy is achieved with the help of the feedback mechanism-driven improved reptile search algorithm,and the comparison experiment verifies the superiority of the feedback mechanism-driven improved reptile search algorithm for the shape optimization problem.

关键词： Reptile search algorithm Feedback mechanism Adaptive parameter Mutation strategy SGC-Ball interpolation developable surface Shape optimization