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Reachability-Based Confidence-Aware Probabilistic Collision Detection in Highway Driving

Engineering 2024年第2期33卷 90-107页

作者： xinwei wang Zirui Li Javier Alonso-Mora Meng wang School of Engineering and Materials Science Queen Mary University of LondonLondon E14NSUK Department of Cognitive Robotics Delft University of TechnologyDelft 2628 CDNetherlands School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China Chair of Traffic Process Automation “Friedrich List”Faculty of Transport and Traffic SciencesTU DresdenDresden 01069Germany

Risk assessment is a crucial component of collision warning and avoidance systems for intelligent vehicles.Reachability-based formal approaches have been developed to ensure driving safety to accurately detect potential vehicle collisions.However,they suffer from over-conservatism,potentially resulting in false–positive risk events in complicated real-world applications.In this paper,we combine two reachability analysis techniques,a backward reachable set(BRS)and a stochastic forward reachable set(FRS),and propose an integrated probabilistic collision–detection framework for highway driving.Within this framework,we can first use a BRS to formally check whether a two-vehicle interaction is safe;otherwise,a prediction-based stochastic FRS is employed to estimate the collision probability at each future time step.Thus,the framework can not only identify non-risky events with guaranteed safety but also provide accurate collision risk estimation in safety-critical events.To construct the stochastic FRS,we develop a neural network-based acceleration model for surrounding vehicles and further incorporate a confidence-aware dynamic belief to improve the prediction accuracy.Extensive experiments were conducted to validate the performance of the acceleration prediction model based on naturalistic highway driving data.The efficiency and effectiveness of the framework with infused confidence beliefs were tested in both naturalistic and simulated highway scenarios.The proposed risk assessment framework is promising for real-world applications.

关键词： Probabilistic collision detection Confidence awareness Probabilistic acceleration prediction Reachability analysis Risk assessment

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Underdetermined direction of arrival estimation with nonuniform linear motion sampling based on a small unmanned aerial vehicle platform

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Defence Technology（防务技术） 2024年第3期33卷 352-363页

作者： xinwei wang Xiaopeng Yan Tai An Qile Chen Dingkun Huang Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China

Uniform linear array(ULA)radars are widely used in the collision-avoidance radar systems of small unmanned aerial vehicles(UAVs).In practice,a ULA's multi-target direction of arrival(DOA)estimation performance suffers from significant performance degradation owing to the limited number of physical elements.To improve the underdetermined DOA estimation performance of a ULA radar mounted on a small UAV platform,we propose a nonuniform linear motion sampling underdetermined DOA estimation method.Using the motion of the UAV platform,the echo signal is sampled at different positions.Then,according to the concept of difference co-array,a virtual ULA with multiple array elements and a large aperture is synthesized to increase the degrees of freedom(DOFs).Through position analysis of the original and motion arrays,we propose a nonuniform linear motion sampling method based on ULA for determining the optimal DOFs.Under the condition of no increase in the aperture of the physical array,the proposed method obtains a high DOF with fewer sampling runs and greatly improves the underdetermined DOA estimation performance of ULA.The results of numerical simulations conducted herein verify the superior performance of the proposed method.

关键词： Unmanned aerial vehicle(UAV) Uniform linear array(ULA) Direction of arrival(DOA) Difference co-array Nonuniform linear motion sampling method

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Cognitive interference decision method for air defense missile fuze based on reinforcement learning

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Defence Technology（防务技术） 2024年第2期32卷 393-404页

作者： Dingkun Huang Xiaopeng Yan Jian Dai xinwei wang Yangtian Liu Science and Technology on Electromechanical Dynamic Control Laboratory School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China

To solve the problem of the low interference success rate of air defense missile radio fuzes due to the unified interference form of the traditional fuze interference system,an interference decision method based Q-learning algorithm is proposed.First,dividing the distance between the missile and the target into multiple states to increase the quantity of state spaces.Second,a multidimensional motion space is utilized,and the search range of which changes with the distance of the projectile,to select parameters and minimize the amount of ineffective interference parameters.The interference effect is determined by detecting whether the fuze signal disappears.Finally,a weighted reward function is used to determine the reward value based on the range state,output power,and parameter quantity information of the interference form.The effectiveness of the proposed method in selecting the range of motion space parameters and designing the discrimination degree of the reward function has been verified through offline experiments involving full-range missile rendezvous.The optimal interference form for each distance state has been obtained.Compared with the single-interference decision method,the proposed decision method can effectively improve the success rate of interference.

关键词： Cognitive radio Interference decision Radio fuze Reinforcement learning Interference strategy optimization

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Constrained docking control for shipborne UAV SideArm recovery

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Chinese Journal of Aeronautics 2024年第5期37卷 39-59页

作者： Zikang SU Zhuolin XING Xuebing LI Chuntao LI xinwei wang Honglun wang College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China School of Engineering and Materials Science Queen Mary University of LondonLondon E14NSUK School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

In this work,we sought to investigate constrained docking control during shipborne SideArm recovery of an Unmanned Aerial Vehicle(UAV)under preassigned safe docking constraints,rough ocean environments,and different initial positions.The aim was to solve the UAV tracking-lag problem that manifests when attempting to dock with a rapidly moving SideArm and to improve the accuracy and rapidity of docking.First,together with the formulations of the shipborne SideArm system and environmental airflows,the affine nonlinear dynamics of the hook was established to reduce tracking lag.Then,echo state network approximators with good approximation capacity and low computational consumption were designed to accurately approximate the UAV’s unknown nonlinear dynamics.With feedforward compensation provided by these approximators,a nonlinear-mapping-based constrained docking control law was developed for shipborne SideArm recovery of UAVs.This approach to controlling the docking trajectory and the forward docking speed of the UAV can achieve rapid and exact docking with a moving SideArm,without violating the preassigned safe docking-constraint envelopes.Simulations under different docking scenarios were used to validate the effectiveness and advantages of the proposed docking-control algorithm.

关键词： SideArm recovery Unmanned aerial vehicle Docking control Nonlinear mapping Echo state network

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Peculiarity of transcriptional and H3K27me3 dynamics during peach bud dormancy

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Horticultural Plant Journal 2024年第1期10卷 38-50页

作者： Yalin Zhao Yong Li Ke Cao Weichao Fang Changwen Chen xinwei wang Jinlong Wu Wenwu Guo Lirong wang The Key Laboratory of Biology and Genetic Improvement of Horticultural Crops(Fruit Tree Breeding Technology) Ministry of AgricultureZhengzhou Fruit Research InstituteChinese Academy of Agricultural SciencesZhengzhouHenan 450009China Western Research Institute Chinese Academy of Agricultural SciencesChangjiXinjiang 831100China College of Horticulture and Forestry Science Huazhong Agricultural UniversityWuhanHubei 430070China

Bud dormancy facilitates the survival of meristems under harsh environmental conditions.To elucidate how molecular responses to chilling accumulation controlling dormancy in peach buds,chromatin immunoprecipitation sequencing to identify the H3K27me3 modifications and RNA sequencing of two peach cultivars with pronounced differences in chilling requirement were carried out,the results showed that genes associated with abscisic acid and gibberellic acid signal pathways play key roles in dormancy regulation.The results demonstrated that peach flower bud differentiation occurred continuously in both cultivars during chilling accumulation,which was correlated with the transcript abundance of key genes involved in phytohormone metabolism and flower bud development under adverse conditions.The more increased strength in high chillingrequirement cultivar along with the chilling accumulation at the genome-wide level.The function of the dormancy-associated MADS-box gene PpDAM6 was identified,which is involved in leaf bud break in peach and flower development in transgenic Nicotiana tabacum(NC89).In addition,PpDAM6 was positively regulated by PpCBF,and the genes of putative dormancy-related and associated with metabolic pathways were proposed.Taken together,these results constituted a theoretical basis for elucidating the regulation of peach bud dormancy transition.

关键词： Peach bud Dormancy RNA-seq H3K27me3 Chilling requirement

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Genomic analysis provides insights into the westward expansion of domesticated peaches in China

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Horticultural Plant Journal 2024年第2期10卷 367-375页

作者： Wenqing Li Yong Li xinwei wang Guoqing Zhao Gengrui Zhu Ke Cao Weichao Fang Jinlong Wu Kai Ma Changwen Chen Lirong wang Zhengzhou Fruit Research Institute CAASZhengzhouHennan 450009China Xinjiang Academy of Agricultural Sciences UrumqiXinjiang 830091China Western Research Institute CAASChangjiXinjiang 831100China

Peach, an economically important model plant of the Rosaceae family, has been domesticated and cultivated in China for approximately5 000 years. The Hexi Corridor, an important corridor connecting east-central China and the Tarim Basin, is the starting point of the Silk Road that links China and the Eurasian region. As a globally distributed fruit tree, the spread of peach was accomplished through historical trade routes in the Hexi Corridor and the Tarim Basin. However, knowledge of peach genetic diversity in these regions remains limited. In this study,we examined the relationships and the spread history of domesticated peaches through sequencing and genomic analysis of 161 peach accessions collected from Northwest China, including 43 from the Hexi Corridor and 104 from the Tarim Basin. The results indicate that peach landraces in the Hexi Corridor and the Tarim Basin are derivatives of peaches from the east and south of China (ESC). Notably, the genetic diversity of accessions from both the Hexi Corridor and the Tarim Basin was lower than that of ESC accessions. Reduction of diversity (ROD) and linkage disequilibrium (LD) analyses detected a genetic bottleneck in peaches from these regions. Additionally, these peaches have undergone varying degrees of selection from natural environment. Moreover, genes responsive to biotic and abiotic stresses were under selection, which could be the result of the climate change of Northwest China after the Last Glacial Maximum (LGM). Our findings provide a better understanding of the genetic basis of peach migration in Northwest China. Furthermore, this study expands the available genomic data for peaches and provides critical information for future peach breeding programs.

关键词： Peach Hexi corridor Tarim Basin Genetic diversity Gene flow

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Target layer state estimation in multi-layer complex dynamical networks considering nonlinear node dynamics

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Chinese Physics B 2024年第4期33卷 245-252页

作者：吴亚勇王欣伟蒋国平 College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China Jiangsu Engineering Laboratory for IOT Intelligent Robots Nanjing 210023China

In many engineering networks, only a part of target state variables are required to be estimated.On the other hand,multi-layer complex network exists widely in practical situations.In this paper, the state estimation of target state variables in multi-layer complex dynamical networks with nonlinear node dynamics is studied.A suitable functional state observer is constructed with the limited measurement.The parameters of the designed functional observer are obtained from the algebraic method and the stability of the functional observer is proven by the Lyapunov theorem.Some necessary conditions that need to be satisfied for the design of the functional state observer are obtained.Different from previous studies, in the multi-layer complex dynamical network with nonlinear node dynamics, the proposed method can estimate the state of target variables on some layers directly instead of estimating all the individual states.Thus, it can greatly reduce the placement of observers and computational cost.Numerical simulations with the three-layer complex dynamical network composed of three-dimensional nonlinear dynamical nodes are developed to verify the effectiveness of the method.

关键词： multi-layer complex dynamical network nonlinear node dynamics target state estimation functional state observer

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Analysis of fluid vibration transfer path and parameter sensitivity of swash plate axial piston pump

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High Technology Letters 2022年第2期28卷 217-226页

作者：赵建华 wang xinwei LIU Hang PEI Youzhi YANG Yong WU Zhaohua wang Jin XING Lanchun DU Guojun Shijiazhuang Haishan Industrial Development Co. Ltd.Shijiazhuang 050200P.R.China Fluid Power Transmission and Control Laboratory Yanshan UniversityQinhuangdao 066004P.R.China College of Civil Engineering and Mechanics Yanshan UniversityQinhuangdao 066004P.R.China

Taking swash plate axial piston pump as the research object,the mechanism of fluid vibration and transfer rule are analyzed.The pump shell can be assumed as the ultimate recipient of vibration transmission,the path model and differential equations from the fluid to the shell are established.The parameters of the path model are determined by the simulation software,and the mathematical model is solved by the simulation software.And time/frequency domain analysis of vibration acceleration of shell is presented.Based on the different influence of various parameters in the transfer path model on transfer characteristics and vibrational recipients,the time-varying parameters are studied by using sensitivity analysis theory,and the influence of the structural parameters on the vibration characteristics of vibration subject is quantitatively analyzed.The research in the paper provides theoretical basis for vibration analysis and structure parameter optimization of axial piston pump.

关键词： axial plunger pump fluid vibration transfer path shell vibration fault analysis

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An Efficient Method for Local Buckling Analysis of Stiffened Panels

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第1期36卷 17-25页

作者： wang xinwei YUAN Zhangxian State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics School of Aerospace Engineering Georgia Institute of Technology

The local buckling of stiffened panels is one of possible failure modes and concerned by engineers in the preliminary design of lightweight structures. In practice,a simplified model,i.e.,a rectangular plate with elastically restrained along its unloaded edges,is established and the Ritz method is usually employed for solutions. To use the Ritz method,however,the loaded edges of the plate are usually assumed to be simply supported. An empirical correction factor has to be used to account for clamped loaded edges. Here,a simple and efficient method,called the quadrature element method(QEM),is presented for obtaining accurate buckling behavior of rectangular plates with any combinations of boundary conditions, including the elastically restrained conditions. Different from the conventional high order finite element method(FEM),non-uniformly distributed nodes are used,and thus the method can achieve an exponential rate of convergence. Formulations are worked out in detail. A computer program is developed. Improvement of solution accuracy can be easily achieved by changing the number of element nodes in the computer program. Several numerical examples are given. Results are compared with either existing solutions or finite element data for verifications. It is shown that high solution accuracy is achieved. In addition,the proposed method and developed computer program can allow quick analysis of local buckling of stiffened panels and thus is suitable for optimization routines in the preliminary design stage.

关键词： local buckling quadrature element method elastically restrained stiffened panel

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Accurate Free Vibration of Functionally Graded Skew Plates

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第2期34卷 188-194页

作者： Jin Chunhua wang xinwei State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics School of Civil Engineering and Architecture Nantong University

The present study aims to analyze free vibration of thin skew plates made of functionally graded material(FGM)by using the weak form quadrature element method.The material properties vary continuously through the thickness according to a power-law form.A novel FGM skew plate element is formulated according to the neutral surface based plate theory and with the help of the differential quadrature rule.For verifications,Numerical results are compared with available data in literature.Results reveal that the non-dimensional frequency parameters of the FGM skew plates are independent of the power-law exponent and always proportional to those of homogeneous isotropic ones when the coupling and rotary inertias are neglected.In addition,employing the physical neutral surface based plate theory is equivalent to using the middle plane based plate theory with the reduced flexural modulus matrix.

关键词： functionally graded material(FGM) skew plate free vibration quadrature element method neutral surface

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