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Asymptotically Optimal Empirical Bayes Estimation of Parameter for Scale-exponential Family under PA Samples 被引量:1
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作者 FAN Guo-liang LING Neng-xiang XU Hong-xia 《Chinese Quarterly Journal of Mathematics》 CSCD 2010年第3期372-378,共7页
The Bayes estimator of the parameter is obtained for the scale exponential family in the case of identically distributed and positively associated(PA) samples under weighted square loss function.We construct the emp... The Bayes estimator of the parameter is obtained for the scale exponential family in the case of identically distributed and positively associated(PA) samples under weighted square loss function.We construct the empirical Bayes(EB) estimator and prove it is asymptotic optimal. 展开更多
关键词 PA samples scale exponential family E·B estimation asymptotical optimality
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ASYMPTOTICALLY OPTIMAL EMPIRICAL BAYES ESTIMATION FOR THE PARAMETERS OF MULTI-PARAMETER DISCRETE EXPONENTIAL FAMILY
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作者 杨亚宁 韦来生 《Acta Mathematica Scientia》 SCIE CSCD 1996年第1期15-22,共8页
For the multi-parameter discrete exponential family,we construct an empirical Bayes(EB)estimator of the vector-valued parameterθ.under some conditions,this estimator is proved to be asymptotically optimal.
关键词 Empirical Bayes estimation asymptotically optimal multi-parameter discrete exp onential family.
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Asymptotically Optimal and Admissible Empirical Bayes Estimation of Normal Parameter
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作者 LIU Huan-xiang SHI Yi-min +1 位作者 ZHANG Su-mei ZHOU Bing-chang 《Chinese Quarterly Journal of Mathematics》 CSCD 北大核心 2007年第1期1-6,共6页
Under square loss, this paper constructs the empirical Bayes(EB) estimation for the parameter of normal distribution which has both asymptotic optimality and admissibility. Moreover, the convergence rate of the EB e... Under square loss, this paper constructs the empirical Bayes(EB) estimation for the parameter of normal distribution which has both asymptotic optimality and admissibility. Moreover, the convergence rate of the EB estimation obtained is proved to be O(n^-1). 展开更多
关键词 empirical Bayes estimation asymptotic optimality ADMISSIBILITY
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Optimal Design of Multiple Stress Constant Accelerated Life Test Plan on Non-rectangle Test Region 被引量:8
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作者 CHEN Wenhua GAO Liang +2 位作者 LIU Juan QIAN Ping PAN Jun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1231-1237,共7页
For optimal design of constant stress accelerated life test(CSALT) with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT desig... For optimal design of constant stress accelerated life test(CSALT) with two-stress, if the stresses could not reach the highest levels simultaneously, the test region becomes non-rectangular. For optimal CSALT design on non-rectangle test region, the present method is only focused on non-rectangle test region with simple boundary, and the optimization algorithm is based on experience which can not ensure to obtain the optimal plan. In this paper, considering the linear-extreme value model and the optimization goal to minimize the variance of lifetime estimate under normal stress, the optimal design method of two-stress type-I censored CSALT plan on general non-rectangular test region is proposed. First, two properties of optimal test plans are proved and the relationship of all the optimal test plans is determined analytically. Then, on the basis of the two properties, the optimal problem is simplified and the optimal design method of two-stress CSALT plan on general non-rectangular test region is proposed. Finally, a numerical example is used to illustrate the feasibility and effectiveness of the method, The result shows that the proposed method could obtain the optimal test plan on non-rectangular test regions with arbitrary boundaries. This research provides the theory and method for two-stress optimal CSALT planning on non-rectangular test regions. 展开更多
关键词 accelerated life test non- rectangular test region test plan optimal design
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THE EXISTENCE AND GLOBAL OPTIMAL ASYMPTOTIC BEHAVIOUR OF LARGE SOLUTIONS FOR A SEMILINEAR ELLIPTIC PROBLEM
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作者 张志军 《Acta Mathematica Scientia》 SCIE CSCD 2008年第3期595-603,共9页
By Karamata regular variation theory and constructing comparison functions, the author shows the existence and global optimal asymptotic behaviour of solutions for a semilinear elliptic problem Δu = k(x)g(u), u ... By Karamata regular variation theory and constructing comparison functions, the author shows the existence and global optimal asymptotic behaviour of solutions for a semilinear elliptic problem Δu = k(x)g(u), u 〉 0, x ∈ Ω, u|δΩ =+∞, where Ω is a bounded domain with smooth boundary in R^N; g ∈ C^1[0, ∞), g(0) = g'(0) = 0, and there exists p 〉 1, such that lim g(sξ)/g(s)=ξ^p, ↓Aξ 〉 0, and k ∈ Cloc^α(Ω) is non-negative non-trivial in D which may be singular on the boundary. 展开更多
关键词 Semilinear elliptic equations explosive subsolutions explosive supersolutions EXISTENCE the global optimal asymptotic behaviour
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Numerical solutions of second order initial value problems of Bratu-type via optimal homotopy asymptotic method
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作者 Mohamed Abdalla Darwish Bothayna S. Kashkari 《American Journal of Computational Mathematics》 2014年第2期47-54,共8页
We present the optimal homotopy asymptotic method (OHAM) to find the numerical solution of the second order initial value problems of Bratu-type. We solve some examples to illustrate the validity and efficiency of the... We present the optimal homotopy asymptotic method (OHAM) to find the numerical solution of the second order initial value problems of Bratu-type. We solve some examples to illustrate the validity and efficiency of the method. 展开更多
关键词 Bratu optimal HOMOTOPY asymptotIC method. numerical solution Initial-value problem
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OPTIMAL HARVESTING POLICY FOR INSHORE-OFFSHORE FISHERY MODEL WITH IMPULSIVE DIFFUSION 被引量:7
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作者 董玲珍 陈兰荪 孙丽华 《Acta Mathematica Scientia》 SCIE CSCD 2007年第2期405-412,共8页
This article studies the inshore-offshore fishery model with impulsive diffusion. The existence and global asymptotic stability of both the trivial periodic solution and the positive periodic solution are obtained. Th... This article studies the inshore-offshore fishery model with impulsive diffusion. The existence and global asymptotic stability of both the trivial periodic solution and the positive periodic solution are obtained. The complexity of this system is also analyzed. Moreover, the optimal harvesting policy are given for the inshore subpopulation, which includes the maximum sustainable yield and the corresponding harvesting effort. 展开更多
关键词 Impulsive diffusion inshore-offshore fishery model global asymptotic stability periodic solution optimal harvesting policy
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An Optimal Design of Accelerated Degradation Tests Based on Degradation Performance
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作者 Yunshun Wu 《Open Journal of Statistics》 2019年第6期686-694,共9页
This paper mainly talks about the relationship between an optimal design of accelerated degradation tests and the degradation performance. When there is a linear relationship between the parameter of distribution and ... This paper mainly talks about the relationship between an optimal design of accelerated degradation tests and the degradation performance. When there is a linear relationship between the parameter of distribution and the critical values, a special pattern of accelerated degradation tests is presented by taking the critical values as accelerated variable. And the optimal test plan is obtained by minimizing the asymptotic variance of the MLE of the parameter of distribution. Finally, a numerical example is presented to illustrate the procedures of the test plan. 展开更多
关键词 ACCELERATED DEGRADATION Test CRITICAL VALUES asymptotIC Variance optimal Design
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Optimal Weights in Nonparametric Analysis of Clustered ROC Curve Data
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作者 Yougui Wu 《Journal of Applied Mathematics and Physics》 2015年第7期828-834,共7页
In diagnostic trials, clustered data are obtained when several subunits of the same patient are observed. Within-cluster correlations need to be taken into account when analyzing such clustered data. A nonparametric m... In diagnostic trials, clustered data are obtained when several subunits of the same patient are observed. Within-cluster correlations need to be taken into account when analyzing such clustered data. A nonparametric method has been proposed by Obuchowski (1997) to estimate the Receiver Operating Characteristic curve area (AUC) for such clustered data. However, Obuchowski’s estimator gives equal weight to all pairwise rankings within and between cluster. In this paper, we modify Obuchowski’s estimate by allowing weights for the pairwise rankings vary across clusters. We consider the optimal weights for estimating one AUC as well as two AUCs’ difference. Our results in this paper show that the optimal weights depends on not only the within-patient correlation but also the proportion of patients that have both unaffected and affected units. More importantly, we show that the loss of efficiency using equal weight instead of our optimal weights can be severe when there is a large within-cluster correlation and the proportion of patients that have both unaffected and affected units is small. 展开更多
关键词 DIAGNOSTIC Test optimal WEIGHT asymptotIC RELATIVE Efficiency Receiver Operating Characteristic CURVE Area under a ROC CURVE
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OPTIMAL POWER ALLOCATION WITH AF AND SDF STRATEGIES IN DUAL-HOP COOPERATIVE MIMO NETWORKS
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作者 Xu Xiaorong Zheng Baoyu Zhang Jianwu 《Journal of Electronics(China)》 2010年第3期328-339,共12页
Dual-hop cooperative Multiple-Input Multiple-Output (MIMO) network with multi-relay cooperative communication is introduced. Power allocation problem with Amplify-and-Forward (AF) and Selective Decode-and-Forward (SDF... Dual-hop cooperative Multiple-Input Multiple-Output (MIMO) network with multi-relay cooperative communication is introduced. Power allocation problem with Amplify-and-Forward (AF) and Selective Decode-and-Forward (SDF) strategies in multi-node scenario are formulated and solved respectively. Optimal power allocation schemes that maximize system capacity with AF strategy are presented. In addition, optimal power allocation methods that minimize asymptotic Symbol Error Rate (SER) with SDF cooperative protocol in multi-node scenario are also proposed. Furthermore, performance comparisons are provided in terms of system capacity and approximate SER. Numerical and simulation results confirm our theoretical analysis. It is revealed that, maximum system capacity could be obtained when powers are allocated optimally with AF protocol, while minimization of system's SER could also be achieved with optimum power allocation in SDF strategy. In multi-node scenario, those optimal power allocation algorithms are superior to conventional equal power allocation schemes. 展开更多
关键词 Dual-hop cooperative Multiple-Input Multiple-Output (MIMO) network optimal power allocation Amplify-and-Forward (AF) Selective Decode-and-Forward (SDF) System capacity asymptotic Symbol Error Rate (SER)
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An Overview of Sequential Approximation in Topology Optimization of Continuum Structure
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作者 Kai Long Ayesha Saeed +6 位作者 Jinhua Zhang Yara Diaeldin Feiyu Lu Tao Tao Yuhua Li Pengwen Sun Jinshun Yan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期43-67,共25页
This paper offers an extensive overview of the utilization of sequential approximate optimization approaches in the context of numerically simulated large-scale continuum structures.These structures,commonly encounter... This paper offers an extensive overview of the utilization of sequential approximate optimization approaches in the context of numerically simulated large-scale continuum structures.These structures,commonly encountered in engineering applications,often involve complex objective and constraint functions that cannot be readily expressed as explicit functions of the design variables.As a result,sequential approximation techniques have emerged as the preferred strategy for addressing a wide array of topology optimization challenges.Over the past several decades,topology optimization methods have been advanced remarkably and successfully applied to solve engineering problems incorporating diverse physical backgrounds.In comparison to the large-scale equation solution,sensitivity analysis,graphics post-processing,etc.,the progress of the sequential approximation functions and their corresponding optimizersmake sluggish progress.Researchers,particularly novices,pay special attention to their difficulties with a particular problem.Thus,this paper provides an overview of sequential approximation functions,related literature on topology optimization methods,and their applications.Starting from optimality criteria and sequential linear programming,the other sequential approximate optimizations are introduced by employing Taylor expansion and intervening variables.In addition,recent advancements have led to the emergence of approaches such as Augmented Lagrange,sequential approximate integer,and non-gradient approximation are also introduced.By highlighting real-world applications and case studies,the paper not only demonstrates the practical relevance of these methods but also underscores the need for continued exploration in this area.Furthermore,to provide a comprehensive overview,this paper offers several novel developments that aim to illuminate potential directions for future research. 展开更多
关键词 Topology optimization sequential approximate optimization convex linearization method ofmoving asymptotes sequential quadratic programming
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Optimal regularity of positive solutions of the Hénon-Hardy equation and related equations
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作者 Zongming Guo Fangshu Wan 《Science China Mathematics》 SCIE CSCD 2024年第10期2283-2302,共20页
We present a new method to determine the optimal regularity of positive solutions u∈C^(4)(Ω\{0})∩C^(0)(Ω) of the Hénon-Hardy equation,i.e.,Δ^(2)u=|x|^(α)u^(p)inΩ,(0,1) where Ω■RN(N≥4) is a bounded smoot... We present a new method to determine the optimal regularity of positive solutions u∈C^(4)(Ω\{0})∩C^(0)(Ω) of the Hénon-Hardy equation,i.e.,Δ^(2)u=|x|^(α)u^(p)inΩ,(0,1) where Ω■RN(N≥4) is a bounded smooth domain with 0∈Ω,α>-4,and p∈R.It is clear that 0 is an isolated singular point of solutions of(0.1) and the optimal regularity of u in Ω relies on the parameter α.It is also important to see that the regularity of u at x=0 determines the regularity of u in Ω.We first establish asymptotic expansions up to arbitrary orders at x=0 of prescribed positive solutions u ∈C^(4)(Ω{0}) ∩ C^(0)(Ω)of(0.1).Then we show that the regularity at x=0 of each positive solution u of(0.1) can be determined by some terms in asymptotic expansions of the related positive radial solution of the equation(0.1) with Ω=B,where B is the unit ball of R^(N).The main idea works for more general equations with singular weights. 展开更多
关键词 H´enon-Hardy equation positive solutions optimal regularity singular point asymptotic expansions
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Modified Augmented Lagrange Multiplier Methods for Large-Scale Chemical Process Optimization 被引量:6
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作者 梁昔明 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2001年第2期167-172,共6页
Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studi... Chemical process optimization can be described as large-scale nonlinear constrained minimization. The modified augmented Lagrange multiplier methods (MALMM) for large-scale nonlinear constrained minimization are studied in this paper. The Lagrange function contains the penalty terms on equality and inequality constraints and the methods can be applied to solve a series of bound constrained sub-problems instead of a series of unconstrained sub-problems. The steps of the methods are examined in full detail. Numerical experiments are made for a variety of problems, from small to very large-scale, which show the stability and effectiveness of the methods in large-scale problems. 展开更多
关键词 modified augmented Lagrange multiplier methods chemical engineering optimization large-scale non- linear constrained minimization numerical experiment
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A Stable Analytical Solution Method for Car-Like Robot Trajectory Tracking and Optimization 被引量:4
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作者 Keyvan Majd Mohammad Razeghi-Jahromi Abdollah Homaifar 《IEEE/CAA Journal of Automatica Sinica》 EI CSCD 2020年第1期39-47,共9页
In this paper, the car-like robot kinematic model trajectory tracking and control problem is revisited by exploring an optimal analytical solution which guarantees the global exponential stability of the tracking erro... In this paper, the car-like robot kinematic model trajectory tracking and control problem is revisited by exploring an optimal analytical solution which guarantees the global exponential stability of the tracking error. The problem is formulated in the form of tracking error optimization in which the quadratic errors of the position, velocity, and acceleration are minimized subject to the rear-wheel car-like robot kinematic model. The input-output linearization technique is employed to transform the nonlinear problem into a linear formulation. By using the variational approach, the analytical solution is obtained, which is guaranteed to be globally exponentially stable and is also appropriate for real-time applications. The simulation results demonstrate the validity of the proposed mechanism in generating an optimal trajectory and control inputs by evaluating the proposed method in an eight-shape tracking scenario. 展开更多
关键词 Global asymptotic stability input-output linearization optimal control trajectory tracking
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Acceleration Factor Harmonious Particle Swarm Optimizer 被引量:2
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作者 Jie Chen Feng Pan Tao Cai 《International Journal of Automation and computing》 EI 2006年第1期41-46,共6页
A Particle Swarm Optimizer (PSO) exhibits good performance for optimization problems, although it cannot guarantee convergence to a global, or even local minimum. However, there are some adjustable parameters, and r... A Particle Swarm Optimizer (PSO) exhibits good performance for optimization problems, although it cannot guarantee convergence to a global, or even local minimum. However, there are some adjustable parameters, and restrictive conditions, which can affect the performance of the algorithm. In this paper, the sufficient conditions for the asymptotic stability of an acceleration factor and inertia weight are deduced, the value of the inertia weight w is enhanced to ( 1, 1). Furthermore a new adaptive PSO algorithm - Acceleration Factor Harmonious PSO (AFHPSO) is proposed, and is proved to be a global search algorithm. AFHPSO is used for the parameter design of a fuzzy controller for a linear motor driving servo system. The performance of the nonlinear model for the servo system demonstrates the effectiveness of the optimized fuzzy controller and AFHPSO. 展开更多
关键词 Particle swarm optimizer acceleration factor harmonious PSO asymptotic stability global convergence fuzzy control.
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THE ASYMPTOTICALLY OPTIMAL EMPIRICALBAYES ESTIMATION IN ONE WAY ANOVA MODEL 被引量:1
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作者 WEI Laisheng (Department of Statistics and Finance, University of Science and Technology of China, Hefei 230026, China) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1999年第1期13-22,共10页
Consider the one-way analysis of variance (ANOVA) model Yij=μ+αi+∈ij,i=1,…,a; j = 1,…,b, ∈ij~N(0, σ2). By using the kernel estimation of multivariate density function and its partial derivatives and making use... Consider the one-way analysis of variance (ANOVA) model Yij=μ+αi+∈ij,i=1,…,a; j = 1,…,b, ∈ij~N(0, σ2). By using the kernel estimation of multivariate density function and its partial derivatives and making use of the estimators of nuisance parameters μ and σ2, we construct the empirical Bayes (EB) estimators of parameter vector α = (α1,…,αa)T. Under the existence condition of the second order moment on prior distribution, we obtain their asymptotic optimality. 展开更多
关键词 asymptotIC optimalITY empirical BAYES estimation ONE WAY ANOVA model.
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Common model analysis and improvement of particle swarm optimizer 被引量:1
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作者 Feng PAN Jie CHEN Minggang GAN Guanghui WANG Tao CAI 《控制理论与应用(英文版)》 EI 2007年第3期233-238,共6页
Particle swarm optimizer (PSO), a new evolutionary computation algorithm, exhibits good performance for optimization problems, although PSO can not guarantee convergence of a global minimum, even a local minimum. Ho... Particle swarm optimizer (PSO), a new evolutionary computation algorithm, exhibits good performance for optimization problems, although PSO can not guarantee convergence of a global minimum, even a local minimum. However, there are some adjustable parameters and restrictive conditions which can affect performance of the algorithm. In this paper, the algorithm are analyzed as a time-varying dynamic system, and the sufficient conditions for asymptotic stability of acceleration factors, increment of acceleration factors and inertia weight are deduced. The value of the inertia weight is enhanced to (-1, 1). Based on the deduced principle of acceleration factors, a new adaptive PSO algorithm- harmonious PSO (HPSO) is proposed. Furthermore it is proved that HPSO is a global search algorithm. In the experiments, HPSO are used to the model identification of a linear motor driving servo system. An Akaike information criteria based fitness function is designed and the algorithms can not only estimate the parameters, but also determine the order of the model simultaneously. The results demonstrate the effectiveness of HPSO. 展开更多
关键词 Particle swarm optimizer asymptotic stability Global convergence System identification Akaike information criteria
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NEW HMM ALGORITHM FOR TOPOLOGY OPTIMIZATION 被引量:4
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作者 Zuo Kongtian ZhaoYudong +2 位作者 Chen Liping Zhong Yifang Huang Yuying 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第3期346-350,共5页
A new hybrid MMA-MGCMMA (HMM) algorithm for solving topology optimization problems is presented. This algorithm combines the method of moving asymptotes (MMA) algorithm and the modified globally convergent version... A new hybrid MMA-MGCMMA (HMM) algorithm for solving topology optimization problems is presented. This algorithm combines the method of moving asymptotes (MMA) algorithm and the modified globally convergent version of the method of moving asymptotes (MGCMMA) algorithm in the optimization process. This algorithm preserves the advantages of both MMA and MGCMMA. The optimizer is switched from MMA to MGCMMA automatically, depending on the numerical oscillation value existing in the calculation. This algorithm can improve calculation efficiency and accelerate convergence compared with simplex MMA or MGCMMA algorithms, which is proven with an example. 展开更多
关键词 Topology optimization Method of moving asymptotes (MMA) Modified globally convergent version of MMA (MGCMMA) HMM algorithm Convergence
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Relevant Region sampling strategy with adaptive heuristic for asymptotically optimal path planning 被引量:2
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作者 Chenming Li Fei Meng +2 位作者 Han Ma Jiankun Wang Max Q-H.Meng 《Biomimetic Intelligence & Robotics》 EI 2023年第3期21-29,共9页
Sampling-based planning algorithm is a powerful tool for solving planning problems in highdimensional state spaces.In this article,we present a novel approach to sampling in the most promising regions,which significan... Sampling-based planning algorithm is a powerful tool for solving planning problems in highdimensional state spaces.In this article,we present a novel approach to sampling in the most promising regions,which significantly reduces planning time-consumption.The RRT#algorithm defines the Relevant Region based on the cost-to-come provided by the optimal forward-searching tree.However,it uses the cumulative cost of a direct connection between the current state and the goal state as the cost-to-go.To improve the path planning efficiency,we propose a batch sampling method that samples in a refined Relevant Region with a direct sampling strategy,which is defined according to the optimal cost-to-come and the adaptive cost-to-go,taking advantage of various sources of heuristic information.The proposed sampling approach allows the algorithm to build the search tree in the direction of the most promising area,resulting in a superior initial solution quality and reducing the overall computation time compared to related work.To validate the effectiveness of our method,we conducted several simulations in both SE(2)and SE(3)state spaces.And the simulation results demonstrate the superiorities of proposed algorithm. 展开更多
关键词 Path planning asymptotical optimality Relevant Region Adaptive heuristic
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LIMITING BEHAVIOR OF RECURSIVE M-ESTIMATORS IN MULTIVARIATE LINEAR REGRESSION MODELS AND THEIR ASYMPTOTIC EFFICIENCIES
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作者 缪柏其 吴月华 刘东海 《Acta Mathematica Scientia》 SCIE CSCD 2010年第1期319-329,共11页
Recursive algorithms are very useful for computing M-estimators of regression coefficients and scatter parameters. In this article, it is shown that for a nondecreasing ul (t), under some mild conditions the recursi... Recursive algorithms are very useful for computing M-estimators of regression coefficients and scatter parameters. In this article, it is shown that for a nondecreasing ul (t), under some mild conditions the recursive M-estimators of regression coefficients and scatter parameters are strongly consistent and the recursive M-estimator of the regression coefficients is also asymptotically normal distributed. Furthermore, optimal recursive M-estimators, asymptotic efficiencies of recursive M-estimators and asymptotic relative efficiencies between recursive M-estimators of regression coefficients are studied. 展开更多
关键词 asymptotic efficiency asymptotic normality asymptotic relative efficiency least absolute deviation least squares M-ESTIMATION multivariate linear optimal estimator reeursive algorithm regression coefficients robust estimation regression model
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