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A Combined Homotopy Interior Point Method for Nonconvex Programming with Pseudo Cone Condition 被引量:13
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作者 于波 刘庆怀 +1 位作者 冯果忱 孙以丰 《Northeastern Mathematical Journal》 CSCD 2000年第4期383-386,共4页
关键词 nonconvex programming interior point method homotopy method
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基于WSS-Pointnet的变电站点云弱监督语义分割方法
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作者 裴少通 孙海超 +2 位作者 胡晨龙 王玮琦 兰博 《电工技术学报》 北大核心 2026年第1期234-245,共12页
现有的变电站点云语义分割算法均采用完全监督学习,需要大量人工标注点云数据,导致分割任务耗时长且成本高昂。为解决这一问题,该文提出一种基于PointNet改进的弱监督语义分割PointNet(WSS-PointNet)算法。首先,通过构建多层降采样结构... 现有的变电站点云语义分割算法均采用完全监督学习,需要大量人工标注点云数据,导致分割任务耗时长且成本高昂。为解决这一问题,该文提出一种基于PointNet改进的弱监督语义分割PointNet(WSS-PointNet)算法。首先,通过构建多层降采样结构,结合采样层与分组层对输入点云数据进行多尺度特征提取,从而捕捉点云在不同尺度上的几何和拓扑信息。在此基础上,引入PointNet结构以进一步提取区域特征,优化局部特征整合与全局特征表示;针对粗粒度语义特征的优化,提出膨胀式语义信息嵌入与浸染式语义信息嵌入两种模块,分别采用“由内而外”和“由外而内”的信息传递策略对点云语义信息进行细致处理,两种嵌入机制均基于图卷积神经网络,通过捕捉局部连接模式与信息共享实现语义特征的高效传播。其次,构建变电站点云数据集,并对WSS-PointNet算法进行消融实验,同时与主流的完全监督学习算法和弱监督学习算法进行对比。经实验验证,WSS-PointNet相比于改进前将变电站点云分割的总体精度(OA)提高了10.3个百分点,平均交并比(mIoU)提高了10.1个百分点,平均准确率(mAcc)提高了10.5个百分点,同时在标注所需时间方面缩短了90%,接近完全监督算法中最好的分割效果。该模型可显著降低处理变电站点云数据的时间与成本,同时保持点云分割的高精度。 展开更多
关键词 点云语义分割 弱监督方法 膨胀式语义信息嵌入 浸染式语义信息嵌入 变电站
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A Combined Homotopy Infeasible Interior-Point Method for Convex Nonlinear Programming 被引量:3
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作者 杨轶华 吕显瑞 刘庆怀 《Northeastern Mathematical Journal》 CSCD 2006年第2期188-192,共5页
In this paper, on the basis of the logarithmic barrier function and KKT conditions, we propose a combined homotopy infeasible interior-point method (CHIIP) for convex nonlinear programming problems. For any convex n... In this paper, on the basis of the logarithmic barrier function and KKT conditions, we propose a combined homotopy infeasible interior-point method (CHIIP) for convex nonlinear programming problems. For any convex nonlinear programming, without strict convexity for the logarithmic barrier function, we get different solutions of the convex programming in different cases by CHIIP method. 展开更多
关键词 convex nonlinear programming infeasible interior point method homotopy method global convergence
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Dynamic economic dispatch combining network flow and interior point method 被引量:1
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作者 韩学山 赵建国 柳焯 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2003年第4期461-466,共6页
Under the environment of electric power market, economic dispatch (ED) problem should consider network constraints, unit ramp rates, besides the basic constraints. For this problem, it is important to establish the ef... Under the environment of electric power market, economic dispatch (ED) problem should consider network constraints, unit ramp rates, besides the basic constraints. For this problem, it is important to establish the effective model and algorithm. This paper examines the decoupled conditions that affect the solution optimality to this problem. It proposes an effective model and solution method. Based on the look-ahead technique, it finds the number of time intervals to guarantee the solution optimality. Next, an efficient technique for finding the optimal solution via the interior point methods is described. Test cases, which include dispatching six units over 5 time intervals on the IEEE 30 test system with line flows and ramp constraints are presented. Results indicate that the computational effort as measured by iteration counts or execution time varies only modestly with the problem size. 展开更多
关键词 Economic dispatch OPTIMIZATION network constraints ramp constraints interior point method
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Element-free Galerkin method for free vibration of rectangular plates with interior elastic point supports and elastically restrained edges 被引量:1
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作者 王砚 王忠民 阮苗 《Journal of Shanghai University(English Edition)》 CAS 2010年第3期187-195,共9页
The element-free Galerkin method is proposed to solve free vibration of rectangular plates with finite interior elastic point supports and elastically restrained edges.Based on the extended Hamilton's principle for t... The element-free Galerkin method is proposed to solve free vibration of rectangular plates with finite interior elastic point supports and elastically restrained edges.Based on the extended Hamilton's principle for the elastic dynamics system,the dimensionless equations of motion of rectangular plates with finite interior elastic point supports and the edge elastically restrained are established using the element-free Galerkin method.Through numerical calculation,curves of the natural frequency of thin plates with three edges simply supported and one edge elastically restrained,and three edges clamped and the other edge elastically restrained versus the spring constant,locations of elastic point support and the elastic stiffness of edge elastically restrained are obtained.Effects of elastic point supports and edge elastically restrained on the free vibration characteristics of the thin plates are analyzed. 展开更多
关键词 element free method rectangular thin plates interior elastic point supports elastically restrained edges free vibration
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A New Infeasible Interior-point Method for Linear Complementarity Problem Based on Full Newton Step 被引量:1
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作者 龚小玉 胡振鹏 王先甲 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第4期624-632,共9页
This paper proposes an infeasible interior-point algorithm with full-Newton step for linear complementarity problem,which is an extension of Roos about linear optimization. The main iteration of the algorithm consists... This paper proposes an infeasible interior-point algorithm with full-Newton step for linear complementarity problem,which is an extension of Roos about linear optimization. The main iteration of the algorithm consists of a feasibility step and several centrality steps. At last,we prove that the algorithm has O(nlog n/ε) polynomial complexity,which coincides with the best known one for the infeasible interior-point algorithm at present. 展开更多
关键词 complementarity problem infeasible interior-point methods full-Newton step polynomial complexity
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Geo-interface modeling with material point method: A review 被引量:1
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作者 Tiancheng Xie Honghu Zhu +4 位作者 Youkou Dong Mingliang Zhou Bin Wang Wei Zhang Jidong Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3950-3972,共23页
Geo-interfaces refer to the contact surfaces between multiple media within geological strata,as well as the transition zones that regulate the migration of three-phase matter,changes in physical states,and the deforma... Geo-interfaces refer to the contact surfaces between multiple media within geological strata,as well as the transition zones that regulate the migration of three-phase matter,changes in physical states,and the deformation and stability of rock and soil masses.Owing to the combined effects of natural factors and human activities,geo-interfaces play crucial roles in the emergence,propagation,and triggering of geological disasters.Over the past three decades,the material point method(MPM)has emerged as a preferred approach for addressing large deformation problems and simulating soil-water-structure interactions,making it an ideal tool for analyzing geo-interface behaviors.In this review,we offer a systematic summary of the basic concepts,classifications,and main characteristics of the geo-interface,and provide a comprehensive overview of recent advances and developments in simulating geo-interface using the MPM.We further present a brief description of various MPMs for modeling different types of geo-interfaces in geotechnical engineering applications and highlight the existing limitations and future research directions.This study aims to facilitate innovative applications of the MPM in modeling complex geo-interface problems,providing a reference for geotechnical practitioners and researchers. 展开更多
关键词 Geo-interface Material point method(MPM) Interaction mechanism Large deformation Numerical simulation
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Optimal Adjustment Algorithm for <i>p</i>Coordinates and The Starting Point in Interior Point Methods 被引量:1
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作者 Carla T. L. S. Ghidini Aurelio R. L. Oliveira Jair Silva 《American Journal of Operations Research》 2011年第4期191-202,共12页
Optimal adjustment algorithm for p coordinates is a generalization of the optimal pair adjustment algorithm for linear programming, which in turn is based on von Neumann’s algorithm. Its main advantages are simplicit... Optimal adjustment algorithm for p coordinates is a generalization of the optimal pair adjustment algorithm for linear programming, which in turn is based on von Neumann’s algorithm. Its main advantages are simplicity and quick progress in the early iterations. In this work, to accelerate the convergence of the interior point method, few iterations of this generalized algorithm are applied to the Mehrotra’s heuristic, which determines the starting point for the interior point method in the PCx software. Computational experiments in a set of linear programming problems have shown that this approach reduces the total number of iterations and the running time for many of them, including large-scale ones. 展开更多
关键词 Von Neumann’s ALGORITHM Mehrotra’s HEURISTIC interior point methods Linear Programming
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A Primal-dual Interior Point Method for Nonlinear Programming 被引量:1
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作者 张珊 姜志侠 《Northeastern Mathematical Journal》 CSCD 2008年第3期275-282,共8页
In this paper, we propose a primal-dual interior point method for solving general constrained nonlinear programming problems. To avoid the situation that the algorithm we use may converge to a saddle point or a local ... In this paper, we propose a primal-dual interior point method for solving general constrained nonlinear programming problems. To avoid the situation that the algorithm we use may converge to a saddle point or a local maximum, we utilize a merit function to guide the iterates toward a local minimum. Especially, we add the parameter ε to the Newton system when calculating the decrease directions. The global convergence is achieved by the decrease of a merit function. Furthermore, the numerical results confirm that the algorithm can solve this kind of problems in an efficient way. 展开更多
关键词 primal-dual interior point algorithm merit function global convergence nonlinear programming
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A NEW FRAMEWORK OF PRIMAL-DUAL INFEASIBLE INTERIOR-POINT METHOD FOR LINEAR PROGRAMMING
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作者 林正华 宋岱才 刘庆怀 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 1998年第2期183-194,共12页
On the basis of the formulations of the logarithmic barrier function and the idea of following the path of minimizers for the logarithmic barrier family of problems the so called "centralpath" for linear pro... On the basis of the formulations of the logarithmic barrier function and the idea of following the path of minimizers for the logarithmic barrier family of problems the so called "centralpath" for linear programming, we propose a new framework of primal-dual infeasible interiorpoint method for linear programming problems. Without the strict convexity of the logarithmic barrier function, we get the following results: (a) if the homotopy parameterμcan not reach to zero,then the feasible set of these programming problems is empty; (b) if the strictly feasible set is nonempty and the solution set is bounded, then for any initial point x, we can obtain a solution of the problems by this method; (c) if the strictly feasible set is nonempty and the solution set is unbounded, then for any initial point x, we can obtain a (?)-solution; and(d) if the strictly feasible set is nonempty and the solution set is empty, then we can get the curve x(μ), which towards to the generalized solutions. 展开更多
关键词 Linear PROGRAMMING infeasible interior-point method HOMOTOPY method global convergence.
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Solving Fixed Point Problems in More General Nonconvex Sets Via an Interior Point Homotopy Method
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作者 SU Meng-long LIU Mai-xue 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第1期74-78,共5页
In this paper,we are mainly devoted to solving fixed point problems in more general nonconvex sets via an interior point homotopy method.Under suitable conditions,a constructive proof is given to prove the existence o... In this paper,we are mainly devoted to solving fixed point problems in more general nonconvex sets via an interior point homotopy method.Under suitable conditions,a constructive proof is given to prove the existence of fixed points,which can lead to an implementable globally convergent algorithm. 展开更多
关键词 nonconvex sets interior point homotopy method
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Globally Convergent Interior Point Methods for Variational Inequalities in Unbounded Sets
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作者 徐庆 于波 +1 位作者 冯果忱 李荣华 《Northeastern Mathematical Journal》 CSCD 2002年第1期9-12,共4页
The finite-dimensional variational inequality problem (VIP) has been studied extensively in the literature because of its successful applications in many fields such as economics, transportation, regional science and ... The finite-dimensional variational inequality problem (VIP) has been studied extensively in the literature because of its successful applications in many fields such as economics, transportation, regional science and operations research. Barker and Pang[1] have given an excellent survey of theories, methods and applications of VIPs. 展开更多
关键词 variational inequality homotopy method interior point method
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A material point finite element method for thermo-hydro-mechanical modeling in poro-elastic media with brittle fracturing
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作者 Zhaonan Wang Louis Ngai Yuen Wong 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3299-3315,共17页
In this study,a powerful thermo-hydro-mechanical(THM)coupling solution scheme for saturated poroelastic media involving brittle fracturing is developed.Under the local thermal non-equilibrium(LTNE)assumption,this sche... In this study,a powerful thermo-hydro-mechanical(THM)coupling solution scheme for saturated poroelastic media involving brittle fracturing is developed.Under the local thermal non-equilibrium(LTNE)assumption,this scheme seamlessly combines the material point method(MPM)for accurately tracking solid-phase deformation and heat transport,and the Eulerian finite element method(FEM)for effectively capturing fluid flow and heat advection-diffusion behavior.The proposed approach circumvents the substantial challenges posed by large nonlinear equation systems with the monolithic solution scheme.The staggered solution process strategically separates each physical field through explicit or implicit integration.The characteristic-based method is used to stabilize advection-dominated heat flows for efficient numerical implementation.Furthermore,a fractional step approach is employed to decompose fluid velocity and pressure,thereby suppressing pore pressure oscillation on the linear background grid.The fracturing initiation and propagation are simulated by a rate-dependent phase field model.Through a series of quasi-static and transient simulations,the exceptional performance and promising potential of the proposed model in addressing THM fracturing problems in poro-elastic media is demonstrated. 展开更多
关键词 Thermo-hydro-mechanical(THM)coupling Local thermal non-equilibrium(LTNE) Material point method(MPM) Characteristic-based method Phase field model
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Sensitivity Analysis of Structural Dynamic Behavior Based on the Sparse Polynomial Chaos Expansion and Material Point Method
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作者 Wenpeng Li Zhenghe Liu +4 位作者 Yujing Ma Zhuxuan Meng Ji Ma Weisong Liu Vinh Phu Nguyen 《Computer Modeling in Engineering & Sciences》 2025年第2期1515-1543,共29页
This paper presents a framework for constructing surrogate models for sensitivity analysis of structural dynamics behavior.Physical models involving deformation,such as collisions,vibrations,and penetration,are devel-... This paper presents a framework for constructing surrogate models for sensitivity analysis of structural dynamics behavior.Physical models involving deformation,such as collisions,vibrations,and penetration,are devel-oped using the material point method.To reduce the computational cost of Monte Carlo simulations,response surface models are created as surrogate models for the material point system to approximate its dynamic behavior.An adaptive randomized greedy algorithm is employed to construct a sparse polynomial chaos expansion model with a fixed order,effectively balancing the accuracy and computational efficiency of the surrogate model.Based on the sparse polynomial chaos expansion,sensitivity analysis is conducted using the global finite difference and Sobol methods.Several examples of structural dynamics are provided to demonstrate the effectiveness of the proposed method in addressing structural dynamics problems. 展开更多
关键词 Structural dynamics DEFORMATION material point method sparse polynomial chaos expansion adaptive randomized greedy algorithm sensitivity analysis
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Interior-Point Methods Applied to the Predispatch Problem of a Hydroelectric System with Scheduled Line Manipulations
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作者 Silvia M. S. Carvalho Aurelio R. L. Oliveira 《American Journal of Operations Research》 2012年第2期266-271,共6页
Transmission line manipulations in a power system are necessary for the execution of preventative or corrective main- tenance in a network, thus ensuring the stability of the system. In this study, primal-dual interio... Transmission line manipulations in a power system are necessary for the execution of preventative or corrective main- tenance in a network, thus ensuring the stability of the system. In this study, primal-dual interior-point methods are used to minimize costs and losses in the generation and transmission of the predispatch active power flow in a hydroelectric system with previously scheduled line manipulations for preventative maintenance, over a period of twenty-four hours. The matrix structure of this problem and the modification that it imposes on the system is also broached in this study. From the computational standpoint, the effort required to solve a problem with or without line manipulations is similar, and the reasons for this are also discussed in this study. Computational results sustain our findings. 展开更多
关键词 interior-point methods Scheduled LINE MANIPULATIONS Hydroelectric Systems The BRAZILIAN Power System
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Kernel Function-Based Primal-Dual Interior-Point Methods for Symmetric Cones Optimization
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作者 ZHAO Dequan ZHANG Mingwang 《Wuhan University Journal of Natural Sciences》 CAS 2014年第6期461-468,共8页
In this paper, we present a large-update primal-dual interior-point method for symmetric cone optimization(SCO) based on a new kernel function, which determines both search directions and the proximity measure betwe... In this paper, we present a large-update primal-dual interior-point method for symmetric cone optimization(SCO) based on a new kernel function, which determines both search directions and the proximity measure between the iterate and the center path. The kernel function is neither a self-regular function nor the usual logarithmic kernel function. Besides, by using Euclidean Jordan algebraic techniques, we achieve the favorable iteration complexity O( √r(1/2)(log r)^2 log(r/ ε)), which is as good as the convex quadratic semi-definite optimization analogue. 展开更多
关键词 symmetric cones optimization Kernel function interior-point method polynomial complexity
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Power Generation Expansion Planning Using an Interior Point with Cutting Plane (IP/CP) Method
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作者 Moon, Guk-Hyun Seo, In-Yong Jaehee, Lee 《Journal of Mechanics Engineering and Automation》 2015年第11期640-645,共6页
The generation expansion planning is one of complex mixed-integer optimization problems, which involves a large number of continuous or discrete decision variables and constraints. In this paper, an interior point wit... The generation expansion planning is one of complex mixed-integer optimization problems, which involves a large number of continuous or discrete decision variables and constraints. In this paper, an interior point with cutting plane (IP/CP) method is proposed to solve the mixed-integer optimization problem of the electrical power generation expansion planning. The IP/CP method could improve the overall efficiency of the solution and reduce the computational time. Proposed method is combined with the Bender's decomposition technique in order to decompose the generation expansion problem into a master investment problem and a slave operational problem. The numerical example is presented to compare with the effectiveness of the proposed algorithm. 展开更多
关键词 Benders' decomposition technique power generation expansion planning interior point with cutting plane method mixed integer programming.
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Fourth Order Compact Finite Volume Methods for 1D Elliptic and Parabolic Equations on Non-uniform Meshes
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作者 ZHOU Lei WANG Feng WANG Tongke 《应用数学》 北大核心 2026年第2期342-359,共18页
This paper studies high order compact finite volume methods on non-uniform meshes for one-dimensional elliptic and parabolic differential equations with the Robin boundary conditions.An explicit scheme and an implicit... This paper studies high order compact finite volume methods on non-uniform meshes for one-dimensional elliptic and parabolic differential equations with the Robin boundary conditions.An explicit scheme and an implicit scheme are obtained by discretizing the equivalent integral form of the equation.For the explicit scheme with nodal values,the algebraic system can be solved by the Thomas method.For the implicit scheme with both nodal values and their derivatives,the system can be implemented by a prediction-correction procedure,where in the correction stage,an implicit formula for recovering the nodal derivatives is introduced.Taking two point boundary value problem as an example,we prove that both the explicit and implicit schemes are convergent with fourth order accuracy with respect to some standard discrete norms using the energy method.Two numerical examples demonstrate the correctness and effectiveness of the schemes,as well as the indispensability of using non-uniform meshes. 展开更多
关键词 Two point boundary value problem Parabolic equation Robin boundary condition Non-uniform mesh Fourth order compact finite volume scheme Predictioncorrection method Error estimate
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Low-order Wavefront Error Compensation for Multi-field of Lithography Projection Objective Based on Interior Point Method
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作者 LU Yutong ZHOU Ji +4 位作者 KANG Xia ZHU Xianchang LIU Junbo WANG Jian HU Song 《Instrumentation》 2022年第3期43-50,共8页
Low-order wavefront error account for a large proportion of wave aberrations.A compensation method for low order aberration of projection lithography objective based on Interior Point Method is presented.Compensation ... Low-order wavefront error account for a large proportion of wave aberrations.A compensation method for low order aberration of projection lithography objective based on Interior Point Method is presented.Compensation model between wavefront error and degree of movable lens freedom is established.Converting over-determined system to underdetermined system,the compensation is solved by Interior Point Method(IPM).The presented method is compared with direct solve the over-determined system.Then,other algorithm GA,EA and PS is compared with IPM.Simulation and experimental results show that the presented compensation method can obtained compensation with less residuals compared with direct solve the over-determined system.Also,the presented compensation method can reduce computation time and obtain results with less residuals compare with AGA,EA and PS.Moreover,after compensation,RMS of wavefront error of the experimental lithography projection objective decrease from 56.05 nm to 17.88 nm. 展开更多
关键词 Wavefront Error Compensation Lithography Projection Objective interior point method Computer Aided Alignment
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A dense mesh optimization method for accelerating electrostatic interaction computation of non-cooperative space targets
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作者 Heng JING Zixuan ZHENG +3 位作者 Dejia CHE Da ZHANG Shulong LI Jianping YUAN 《Chinese Journal of Aeronautics》 2026年第2期499-516,共18页
Computing electrostatic interaction on non-cooperative targets with unknown meshes is crucial for electrostatic-based space on-orbit services.Although meshes for electrostatic interaction computations can be reconstru... Computing electrostatic interaction on non-cooperative targets with unknown meshes is crucial for electrostatic-based space on-orbit services.Although meshes for electrostatic interaction computations can be reconstructed from point clouds,they are usually too dense,leading to high computational costs.This paper presents an optimization method for converting dense meshes into optimal meshes,enabling fast and accurate computation of the electrostatic interaction by point clouds.First,the dense mesh reconstructed from point clouds is simplified into a coarse mesh using local operators.Second,the simplified mesh is refined by an iterative strategy that integrates a lightweight method of moments and an impedance matrix inheritance technique,ultimately yielding an optimal mesh for computing the electrostatic interaction.Simulation results show that our method effectively optimizes dense meshes,making electrostatic interaction computations using point clouds approximately 63.4 times more efficient than the previous method. 展开更多
关键词 Non-cooperative target Electrostatic interaction method of moments point cloud Mesh optimization
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