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Chinese Journal of Aeronautics 2015年第1期28卷 152-163页

作者： tian Yongliang Liu Hu Yin jiao Luo Mingqiang Wu Guanghui School of Aeronautic Science and Engineering Beihang University Chengdu Aircraft Design Institute Commercial Aircraft Corporation of China Ltd.

Simulation-based training is a promising way to train a carrier flight deck crew because of the complex and dangerous working environment. Quantitative evaluation of simulation-based training quality is vital to make simulation-based training practical for aircraft carrier *** paper develops a personal computer-based aircraft carrier marshalling simulation system and a cave automatic virtual environment（CAVE）-based immersive environment. In order to compare the training effectiveness of simulation-based training and paper-based training, a learning cubic model is proposed and a contrast experiment is carried out as well. The experimental data is analyzed based on a simplified Kirkpatrick＇s model. The results show that simulation-based training is better than paper-based training by 26.80% after three rounds of testing, which prove the effectiveness of simulation-based aircraft carrier marshalling training.

关键词： aircraft cubic dangerous simplified questionnaire vital train deviation pyramid judge

Multi-objective energy management for PHEV using Pontryagin's minimum principle and particle swarm optimization online

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Science China(Information Sciences) 2021年第1期64卷 263-265页

作者： Yuying wang Xiaohong jiao Institute of Electric Engineering Yanshan University

Dear editor,Plug-in hybrid electric vehicles (PHEVs),which can be charged through an external power grid,have been regarded as one of the research areas for the developing methods to reduce petroleum demand and exhaust *** management strategies (EMSs) are crucial for reducing the energy consumption for PHEVs because the power demands during the driving cycle are usually provided by multiple energy *** addition,PHEVs are often equipped with high-cost batteries,which need to be charged and discharged *** indicates that,to achieve the economic feasibility of PHEVs,battery health cannot be ignored with respect to energy management [1].

关键词： plug-in hybrid electric vehicle energy management strategy multi-objective Pontryagin's minimum principle particle swarm optimization

Digital Twin for Human-Robot Interactive Welding and Welder Behavior Analysis

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IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 334-343页

作者： Qiyue wang Wenhua jiao Peng wang YuMing Zhang Institute for Sustainable Manufacturing and the Department of Electrical and Computer Engineering University of KentuckyLexingtonKY 40506 USA the Institute for Sustainable Manufacturing and the Department of Electrical and Computer Engineering and also with the Department of Mechanical EngineeringUniversity of KentuckyLexingtonKY 40506 USA

This paper presents an innovative investigation on prototyping a digital twin(DT)as the platform for human-robot interactive welding and welder behavior *** humanrobot interaction(HRI)working style helps to enhance human users'operational productivity and comfort;while data-driven welder behavior analysis benefits to further novice welder *** HRI system includes three modules:1)a human user who demonstrates the welding operations offsite with her/his operations recorded by the motion-tracked handles;2)a robot that executes the demonstrated welding operations to complete the physical welding tasks onsite;3)a DT system that is developed based on virtual reality(VR)as a digital replica of the physical human-robot interactive welding *** DT system bridges a human user and robot through a bi-directional information flow:a)transmitting demonstrated welding operations in VR to the robot in the physical environment;b)displaying the physical welding scenes to human users in *** to existing DT systems reported in the literatures,the developed one provides better capability in engaging human users in interacting with welding scenes,through an augmented *** verify the effectiveness,six welders,skilled with certain manual welding training and unskilled without any training,tested the system by completing the same welding job;three skilled welders produce satisfied welded workpieces,while the other three unskilled do not.A data-driven approach as a combination of fast Fourier transform(FFT),principal component analysis(PCA),and support vector machine(SVM)is developed to analyze their *** an operation sequence,i.e.,motion speed sequence of the welding torch,frequency features are firstly extracted by FFT and then reduced in dimension through PCA,which are finally routed into SVM for *** trained model demonstrates a 94.44%classification accuracy in the testing *** successful pattern recognition in skilled

关键词： Digital twin(DT) human-robot interaction(HRI) machine learning virtual reality(VR) welder behavior analysis

Solute transport characteristics of a deep soil profile in the Loess Plateau,China

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Journal of Arid Land 2018年第4期10卷 628-637页

作者： wang jiao SHAO Ming'an Key Laboratory of Ecosystems Network Observation and Modeling Institute of Geographical Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Northwest A&F UniversityYangling 712100China

Understanding solute transport behaviors of deep soil profile in the Loess Plateau is helpful for ecological construction and agricultural production improvement. In this study, solute transport processes of a deep soil profile were measured by a conservative tracer experiment using 25 undisturbed soil cores （20 cm long and 7 cm diameter for each） continuously sampled from the surface downward to the depth of 500 cm in the Loess Plateau of China. The solute transport breakthrough curves （BTCs） were analyzed in terms of the convection-dispersion equation （CDE） and the mobile-immobile model （MIM）. Average pore-water velocity and dispersion coefficient （or effective dispersion coefficient） were calculated using the CDE and MIM. Basic soil properties and water infiltration parameters were also determined to explore their influence on the solute transport parameters. Both pore-water velocity and dispersion coefficient （or effective dispersion coefficient） generally decreased with increasing depth, and the dispersivity fluctuated along the soil profile. There was a good linear correlation between log-transformed pore-water velocity and dispersion coefficient, with a slope of about 1.0 and an average dispersivity of 0.25 for the entire soil profile. Generally speaking, the soil was more homogeneous along the soil profile. Our results also show that hydrodynamic dispersion is the dominant mechanism of solute transport of loess soils in the study area.

关键词： solute transport loess soil pore-water velocity dispersion coefficient hydraulic conductivity Loess Plateau

Numerical and theoretical investigations of heat transfer characteristics in helium-xenon cooled microreactor core

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Nuclear Science and Techniques 2023年第11期34卷 1-19页

作者： tian‑Shi wang Xiang Chai Chao‑Ran Guan Xin‑Yue Liu jiao‑Long Deng Hui He Xiao‑Jing Liu School of Nuclear Science and Engineering Shanghai JiaoTong UniversityShanghai 200240China

Helium-xenon cooled microreactors are a vital technological solution for portable nuclear reactor power *** exam-ine the convective heat transfer behavior of helium-xenon gas mixtures in a core environment,numerical simulations are conducted on a cylindrical coolant channel and its surrounding solid *** numerical methods are used to determine the effect and mechanisms of power and its distribution,inlet temperature and velocity,and outlet pressure on the distribution and change trend of the axial Nusselt ***,a theoretical framework that can describe the effect of power variation on the evolution of the thermal boundary layer is employed to formulate an axial distribution cor-relation for the Nusselt number of the coolant channel,under the assumption of a cosine distribution for the axial *** on the simulation results,the correlation coefficients are determined,and a semi-empirical relationship is identified under the corresponding operating *** correlation derived in this study is consistent with the simulations,with an average relative error of 5.3%under the operating ***,to improve the accuracy of the predictions near the entrance,a segmented correlation is developed by combining the Kays correlation with the aforementioned *** new correlation reduces the average relative error to 2.9%and maintains satisfactory accuracy throughout the entire axial range of the channel,thereby demonstrating its applicability to turbulent heat transfer calculations for helium-xenon gas mixtures within the core *** findings provide valuable insights into the convective heat transfer behavior of a helium-xenon gas mixture in a core environment.

关键词： Helium-xenon gas mixture Convective heat transfer Power distribution Numerical simulation Nusselt number correlation

Unsteady aerodynamics modeling for flight dynamics application

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Acta Mechanica Sinica 2012年第1期28卷 14-23页

作者： Qing wang Kai-Feng He. Wei-Qi Qian tian-jiao Zhang Yan-Qing Cheng Kai-Yuan Wu State Key Laboratory of Aerodynamics 621000 MianyangChina Computational Aerodynamics Institute China Aerodynamics Research and Development Center621000 MianyangChina Scientific Research Base of Flight Technology and Safety Civil Aviation Flight University of China618307 GuanghanChina

In view of engineering application, it is practicable to decompose the aerodynamics into three components： the static aerodynamics, the aerodynamic increment due to steady rotations, and the aerodynamic increment due to unsteady separated and vortical flow. The first and the second components can be presented in conventional forms, while the third is described using a one-order differential equation and a radial-basis-function （RBF） network. For an aircraft configuration, the mathematical models of 6- component aerodynamic coefficients are set up from the wind tunnel test data of pitch, yaw, roll, and coupled yawroll large-amplitude oscillations. The flight dynamics of an aircraft is studied by the bifurcation analysis technique in the case of quasi-steady aerodynamics and unsteady aerodynam- ics, respectively. The results show that：（1） unsteady aerodynamics has no effect upon the existence of trim points, but affects their stability; （2） unsteady aerodynamics has great effects upon the existence, stability, and amplitudes of periodic solutions; and （3） unsteady aerodynamics changes the stable regions of trim points obviously. Furthermore, the dynamic responses of the aircraft to elevator deflections are inspected. It is shown that the unsteady aerodynamics is beneficial to dynamic stability for the present aircraft. Finally, the effects of unsteady aerodynamics on the post-stall maneuverability

关键词： Unsteady aerodynamics High angle of attack Mathematical model Flight dynamics - Bifurcation analysis Post-stall maneuver

Mechanical properties and friction behaviors of CNT/AlSi_(10)Mg composites produced by spark plasma sintering

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International Journal of Minerals,Metallurgy and Materials 2017年第5期24卷 584-593页

作者： Lin-zhi wang Ying Liu jiao-jiao Wu Xi Zhang Chongqing Key Laboratory of Additive Manufacturing Technology and Systems Chongqing Institute of Green and Intelligent TechnologyChinese Academy of Sciences College of Material Science and Engineering Sichuan University College of Material Science and Engineering Southwest Jiaotong university

The mechanical properties and friction behaviors of CNT/AlSi10Mg composites produced by spark plasma sintering (SPS) were investigated. The results showed that the densities of the sintered composites gradually increased with increasing sintering temperature and that the highest microhardness and compressive strength were achieved in the specimen sintered at 450A degrees C. CNTs dispersed uniformly in the Al-Si10Mg matrix when the addition of CNTs was less than 1.5wt%. However, when the addition of CNTs exceeded 1.5wt%, the aggregation of CNTs was clearly observed. Moreover, the mechanical properties (including the densities, compressive strength, and microhardness) of the composites changed with CNT content and reached a maximum value when the CNT content was 1.5wt%. Meanwhile, the minimum average friction coefficient and wear rate of the CNT/AlSi10Mg composites were obtained with 1.0wt% CNTs.

关键词： metal matrix composites carbon nanotubes (CNTs) aluminum silicon magnesium alloys spark plasma sintering mechanical properties friction

Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 380-390页

作者： Yishuang Yu Jingxiao Zhao Xuelin wang Hui Guo Zhenjia Xie Chengjia Shang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic *** results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without ***,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to *** improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant ***,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant *** findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels.

关键词： high-strength steel cobalt transformation kinetics crystallography impact toughness

Learning a discriminative high-fidelity dictionary for single channel source separation

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1097-1110页

作者： tian Yuanrong wang Xing School of Electronic Countermeasure National University of Defense TechnologyHefei 230037China Institute of Aeronautics Engineering Air Force Engineering UniversityXi’an 710038China

Sparse-representation-based single-channel source separation,which aims to recover each source’s signal using its corresponding sub-dictionary,has attracted many scholars’*** basic premise of this model is that each sub-dictionary possesses discriminative information about its corresponding source,and this information can be used to recover almost every sample from that ***,in a more general sense,the samples from a source are composed not only of discriminative information but also common information shared with other *** paper proposes learning a discriminative high-fidelity dictionary to improve the separation *** innovations are ***,an extra sub-dictionary was combined into a conventional union dictionary to ensure that the source-specific sub-dictionaries can capture only the purely discriminative information for their corresponding sources because the common information is collected in the additional ***,a task-driven learning algorithm is designed to optimize the new union dictionary and a set of weights that indicate how much of the common information should be allocated to each ***,a source separation scheme based on the learned dictionary is *** results on a human speech dataset yield evidence that our algorithm can achieve better separation performance than either state-of-the-art or traditional algorithms.

关键词： single channel source separation sparse representation dictionary learning discrimination high-fidelity

A Note on Determine the Greatest Common Subfamily of Two NFSRs by Grbner Basis

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Journal of Systems Science & Complexity 2015年第5期28卷 1231-1242页

作者： wang Zhongxiao QI Wenfeng tian tian Luoyang University of Foreign Language State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Information Science and Technology Institute

For nonlinear feedback shift registers(NFSRs), their greatest common subfamily may be not unique. Given two NFSRs, the authors only consider the case that their greatest common subfamily exists and is unique. If the greatest common subfamily is exactly the set of all sequences which can be generated by both of them, the authors can determine it by Grbner basis theory. Otherwise, the authors can determine it under some conditions and partly solve the problem.

关键词： Greatest common subfamily Grbner basis nonlinear feedback shift register stream cipher