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Chinese Journal of Aeronautics 2024年第2期37卷 524-540页

作者： Xuan CUI Rui zhao Min WAN School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material *** develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 *** research focused on the two most widely recognized effects:the Joule thermal and the electric athermal *** mechanism of current action can be divided into two scenarios:one considering the Joule thermal effect only,and the other considering both effects *** basic constitutive models,namely the Modified-Hollomon model and the Johnson-Cook(J-C)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were *** was found that the J-C model with simultaneous consideration of the Joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four ***,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization *** results show that the constitutive model can effectively predict the temperature effect caused by the Joule heat effect and the athermal effect of current on the material.

关键词： Joule heating Elastoplasticity Plastic deformation Superalloys Constitutive models

Regression Analysis of Interval-Censored Data with Informative Observation Times Under the Accelerated Failure Time Model

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Journal of Systems Science & Complexity 2022年第4期35卷 1520-1534页

作者： zhao Shishun DONG Lijian SUN Jianguo Center for Applied Statistical Research School of MathematicsJilin UniversityChangchun130012China Department of Statistics University of MissouriColumbiaMO65211USA

This paper discusses regression analysis of interval-censored failure time data arising from the accelerated failure time model in the presence of informative *** the problem,a sieve maximum likelihood estimation approach is proposed and in the method,the copula model is employed to describe the relationship between the failure time of interest and the censoring or observation *** I-spline functions are used to approximate the unknown functions in the model,and a simulation study is carried out to assess the finite sample performance of the proposed approach and suggests that it works well in practical *** addition,an illustrative example is provided.

关键词： Accelerated failure time model copula models informative censoring interval-censored data splines

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The Strategic Analysis of Demand Forecast-Sharing in a Hybrid-Format Online Platform Supply Chain

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Journal of Systems Science and Systems Engineering 2024年第3期33卷 281-310页

作者： Jing zhao Zijun Yin Guobiao Zhou School of Mathematical Sciences Tiangong UniversityTianjin300387China

This paper examines the optimal forecast-sharing strategy in a hybrid-format online platform supply chain where a supplier sells a product through agency format and reselling format provided by a platform retailer who possesses demand forecasts from two *** asymmetry and co-opetitive relationship arise between the platform retailer and the supplier,which affect their operational decisions and the supply chain’s *** improve supply chain efficiency,we compare different forecast-sharing strategies(i.e.,no forecast sharing,sharing a single forecast,and sharing two forecasts),and analyze the effects of co-opetitive parameters on the optimal forecast-sharing *** analysis shows that forecast sharing is always beneficial to the supplier,and sharing two forecasts is more beneficial than sharing a single *** for the platform retailer and the whole supply chain,forecast sharing is beneficial only under certain conditions,depending on the co-opetitive *** optimal forecast-sharing strategy is the result of a combination of the negative effect of double marginalization in reselling channel and the positive effect of responding pricing to demand uncertainty in agency *** illustrate the parameter regions of the platform retailer’s voluntary sharing,contract sharing,and no sharing,and also find that higher channel competition intensity,higher market share of agency channel,and higher commission rate can promote the platform retailer’s voluntary *** study extends the research scope of demand forecast-sharing and sheds light on the decision-making processes for managing a hybrid-format online platform supply chain.

关键词： Supply chain management hybrid-format online platform demand forecast-sharing co-opetitive relationship channel competition intensity

Adaptive neural networks control for uncertain parabolic distributed parameter systems with nonlinear periodic time-varying parameter

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Science China(Technological Sciences) 2022年第7期65卷 1482-1492页

作者： LEI YanFang LI JunMin zhao AiLiang School of Mathematic and Statistics Xidian UniversityXi'an 710716China

This paper studies the problem of adaptive neural networks control(ANNC) for uncertain parabolic distributed parameter systems(DPSs) with nonlinear periodic time-varying parameter(NPTVP). Firstly, the uncertain nonlinear dynamic and unknown periodic TVP are represented by using neural networks(NNs) and Fourier series expansion(FSE), respectively. Secondly, based on the ANNC and reparameterization approaches, two control algorithms are designed to make the uncertain parabolic DPSs with NPTVP asymptotically stable. The sufficient conditions of the asymptotically stable for the resulting closed-loop systems are also derived. Finally, a simulation is carried out to verify the effectiveness of the two control algorithms designed in this work.

关键词： nonlinear parabolic distributed parameter systems adaptive neural networks control Fourier series expansion asymptotically stable

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Understanding Human and Machine Interaction from Decision Perspective: An Empirical Study Based on the Game of Go

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Journal of Systems Science & Complexity 2024年第2期37卷 647-667页

作者： zhao Ping LI Xuerong WANG Shouyang Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100190China

The authors aim to interpret human and AI interactions from the decision *** authors decompose the interaction analysis into the following main components in the context of interactions:Individual behavior patterns,interaction relationships,and comprehensive *** authors interpret intertemporal decisions from a physical perspective and employ cross-discipline concepts and methodologies to extract the behavior characteristics of players in the empirical case *** the individual behavior patterns,the authors find that human players prefer short-term periods to AI in *** interaction relationship analysis reveals a dynamic relationship between possible short-term co-movement and nearly counter-movement in the long *** authors apply principal component analysis to descriptive indicators and discover a regular decision *** main behavior pattern of players in the game of Go is switching between careful and daring *** differences in the decision hierarchies imply a discrepancy of patience between humans and AI.

关键词： Coherence analysis decision hierarchy machine behaviour multitaper spectral analysis

Adaptive level of autonomy for human-UAVs collaborative surveillance using situated fuzzy cognitive maps

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Chinese Journal of Aeronautics 2020年第11期33卷 2835-2850页

作者： Zhe zhao Yifeng NIU Lincheng SHEN College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

Collaborating with a squad of Unmanned Aerial Vehicles(UAVs)is challenging for a human operator in a cooperative surveillance *** this paper,we propose a cognitive model that can dynamically adjust the Levels of Autonomy(LOA)of the human-UAVs team according to the changes in task complexity and human cognitive ***,we use the Situated Fuzzy Cognitive Map(Si FCM)to model the relations among tasks,situations,human states and LOA.A recurrent structure has been used to learn the strategy of adjusting the LOA,while the collaboration task is separated into a perception routine and a control *** results have shown that the workload of the human operator is well balanced with the task efficiency.

关键词： Adaptive LOA Cognitive Model Human-UAVs collaboration Situated Fuzzy Cognitive Map(SiFCM) Time series learning

Transcriptome changes in Polygonum multiflorum Thunb. roots induced by methyl jasmonate

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2015年第12期16卷 1027-1041页

作者： Hong-chang LIU Wei WU Kai HOU Jun-wen CHEN Zhi zhao College of Agronomy Sichuan Agricultural University Guizhou key (Engineering) Laboratory for Propagation and Cultivation of Medicinal Plants

Transcriptome profiling has been widely used to analyze transcdptomic variation in plants subjected to abiotic or biotic stresses. Although gene expression changes induced by methyl jasmonate （MeJA） have been profiled in several plant species, no information is available on the MeJA-triggered transcriptome response of Polygonum multiflorum Thunb., a species with highly valuable medicinal properties. In this study, we used transcriptome profiling to investigate transcdptome changes in roots of P. mu/tiflorum seedlings subjected to a 0.25 mmol/L-MeJA rootirrigation treatment. A total of 18 677 differentially expressed genes （DEGs） were induced by MeJA treatment, of which 4535 were up-regulated and 14 142 were down-ragulated compared with controls. These DEGs were associated with 125 metabolic pathways. In addition to various common primary and secondary metabolic pathways, several sec- ondary metabolic pathways related to components with significant pharmacological effects were enriched by MeJA, including arachidonic acid metabolism, linoleic acid metabolism, and stilbenoid biosynthesis. The MeJA-induced transcdptome changes uncovered in this study provide a solid foundation for future study of functional genes controlling effective components in secondary metabolic pathways of P. multiflorum.

关键词： Polygonum multiflorum Thunb. Methyl jasmonate Transcriptome change Differentially expressed genes

Survey on research and development of on-orbit active debris removal methods

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Science China(Technological Sciences) 2020年第11期63卷 2188-2210页

作者： zhao PengYuan LIU JinGuo WU ChenChen State key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China

Space debris is growing dramatically with the rapid pace of human exploration of space,which seriously threatens the safety of artificial spacecraft in ***,the active debris removal(ADR)is *** review aims to review the ADR methods and to advance related research in the *** current research and development status are clearly demonstrated by mapping knowledge domain and *** this paper,the latest research results are classified and summarized in detail from two aspects of space debris capture and *** scheme comparison and evaluation of all ADR methods are performed,and the applicable scopes of various methods are *** ADR method is scored using a cobweb evaluation model based on six *** development of ADR is discussed to promote further research interest.

关键词： space debris active debris removal on-orbit servicing space robotics capture method

A symplectic finite element method based on Galerkin discretization for solving linear systems

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Applied Mathematics and Mechanics(English Edition) 2023年第8期44卷 1305-1316页

作者： Zhiping QIU zhao WANG Bo ZHU Institute of Solid Mechanics School of Aeronautic Science and EngineeringBeihang UniversityBeijing 100083China

We propose a novel symplectic finite element method to solve the structural dynamic responses of linear elastic *** the dynamic responses of continuous medium structures,the traditional numerical algorithm is the dissipative algorithm and cannot maintain long-term energy ***,a symplectic finite element method with energy conservation is constructed in this paper.A linear elastic system can be discretized into multiple elements,and a Hamiltonian system of each element can be *** single element is discretized by the Galerkin method,and then the Hamiltonian system is constructed into the Birkhoffian ***,all the elements are combined to obtain the vibration equation of the continuous system and solved by the symplectic difference *** the numerical experiments of the vibration response of the Bernoulli-Euler beam and composite plate,it is found that the vibration response solution and energy obtained with the algorithm are superior to those of the Runge-Kutta *** results show that the symplectic finite element method can keep energy conservation for a long time and has higher stability in solving the dynamic responses of linear elastic systems.

关键词： Galerkin finite element method linear system structural dynamic response symplectic difference scheme

Research on Piezoelectric Driving Microminiature Three-Legged Crawling Robot

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Journal of Bionic Engineering 2023年第4期20卷 1481-1492页

作者： Zhongyuan Zheng Yanru zhao Geng Wang School of Mechanical and Power Engineering Henan Polytechnic UniversityJiaozuo454000China key Laboratory of Testing Technology for Manufacturing Process of Ministry of Education Southwest University of Science and TechnologyMianyang621010China

Micro-robots have the characteristics of small size,light weight and flexible *** design a micro three-legged crawling robot with multiple motion directions,a novel driving scheme based on the inverse piezoelectric effect of piezoelectric ceramics was *** three legs of the robot were equipped with piezoelectric bimorphs as drivers,*** motion principles were analyzed and the overall force analysis was carried out with the theoretical mechanics *** natural frequency,mode shape and amplitude were analyzed with simulation software COMSOL Multiphysics,the optimal size was determined through parametric analysis,and then the micro three-legged crawling robot was *** effects of different driving voltages,different driving frequencies,different motion bases and different loads on the motion speed of the robot were *** is shown that the maximum speed of single-leg driving was 35.41 cm/s,the switching ability between different motion directions was measured,and the movements in six different directions were *** is demonstrated the feasibility of multi-directional motion of the *** research may provide a reference for the design and development of miniature piezoelectric three-legged crawling robots.

关键词： Three-legged crawling robot Piezoelectric drive Mechanical property analysis Kinematic features analysis