期刊文献+
共找到914篇文章
< 1 2 46 >
每页显示 20 50 100
A New Technique for Estimating the Lower Bound of the Trust-Region Subproblem
1
作者 Xinlong Luo 《Applied Mathematics》 2011年第4期424-426,共3页
Trust-region methods are popular for nonlinear optimization problems. How to determine the predicted reduction of the trust-region subproblem is a key issue for trust-region methods. Powell gave an estimation of the l... Trust-region methods are popular for nonlinear optimization problems. How to determine the predicted reduction of the trust-region subproblem is a key issue for trust-region methods. Powell gave an estimation of the lower bound of the trust-region subproblem by considering the negative gradient direction. In this article, we give an alternate way to estimate the same lower bound of the trust-region subproblem. 展开更多
关键词 trust-region METHOD UNCONSTRAINED OPTIMIZATION trust-region Subproblem
在线阅读 下载PDF
Adaptive Conic Trust-Region Method for Nonlinear Least Squares Problems 被引量:3
2
作者 Yang Yang Sun Wenyu 《南京师大学报(自然科学版)》 CAS CSCD 北大核心 2007年第1期13-21,共9页
关键词 非线性最小二乘问题 自适应锥模型 算法
在线阅读 下载PDF
A FILTER-TRUST-REGION METHOD FOR LC^1 UNCONSTRAINED OPTIMIZATION AND ITS GLOBAL CONVERGENCE 被引量:1
3
作者 ZhenghaoYang Wenyu Sun Chuangyin Dang 《Analysis in Theory and Applications》 2008年第1期55-66,共12页
In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorith... In this paper we present a filter-trust-region algorithm for solving LC1 unconstrained optimization problems which uses the second Dini upper directional derivative. We establish the global convergence of the algorithm under reasonable assumptions. 展开更多
关键词 nonsmooth optimization filter method trust region algorithm global conver- gence LC1 optimization
在线阅读 下载PDF
Projected gradient trust-region method for solving nonlinear systems with convex constraints
4
作者 JIA Chun-xia ZHU De-tong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2011年第1期57-69,共13页
In this paper, a projected gradient trust region algorithm for solving nonlinear equality systems with convex constraints is considered. The global convergence results are developed in a very general setting of comput... In this paper, a projected gradient trust region algorithm for solving nonlinear equality systems with convex constraints is considered. The global convergence results are developed in a very general setting of computing trial directions by this method combining with the line search technique. Close to the solution set this method is locally Q-superlinearly convergent under an error bound assumption which is much weaker than the standard nonsingularity condition. 展开更多
关键词 Nonlinear equation trust region method projected gradient local error bound.
在线阅读 下载PDF
A nonmonotone adaptive trust-region algorithm for symmetric nonlinear equations
5
作者 Gong-Lin Yuan Cui-Ling Chen Zeng-Xin Wei 《Natural Science》 2010年第4期373-378,共6页
In this paper, we propose a nonmonotone adap-tive trust-region method for solving symmetric nonlinear equations problems. The convergent result of the presented method will be estab-lished under favorable conditions. ... In this paper, we propose a nonmonotone adap-tive trust-region method for solving symmetric nonlinear equations problems. The convergent result of the presented method will be estab-lished under favorable conditions. Numerical results are reported. 展开更多
关键词 TRUST Region Method Global Con-vergence SYMMETRIC Nonlinear EQUATIONS
在线阅读 下载PDF
STOCHASTIC TRUST-REGION METHODS WITH TRUST-REGION RADIUS DEPENDING ON PROBABILISTIC MODELS 被引量:2
6
作者 Xiaoyu Wang Ya-xiang Yuan 《Journal of Computational Mathematics》 SCIE CSCD 2022年第2期294-334,共41页
We present a stochastic trust-region model-based framework in which its radius is related to the probabilistic models.Especially,we propose a specific algorithm termed STRME,in which the trust-region radius depends li... We present a stochastic trust-region model-based framework in which its radius is related to the probabilistic models.Especially,we propose a specific algorithm termed STRME,in which the trust-region radius depends linearly on the gradient used to define the latest model.The complexity results of the STRME method in nonconvex,convex and strongly convex settings are presented,which match those of the existing algorithms based on probabilistic properties.In addition,several numerical experiments are carried out to reveal the benefits of the proposed methods compared to the existing stochastic trust-region methods and other relevant stochastic gradient methods. 展开更多
关键词 trust-region methods Stochastic optimization Probabilistic models trust-region radius Global convergence
原文传递
A Trust-region Algorithm for Nonlinear Constrained Optimization Problem
7
作者 童小娇 周叔子 《Journal of Mathematical Research and Exposition》 CSCD 北大核心 2004年第3期445-460,共16页
This paper presents a new trust-region algorithm for general nonlinear constrained optimization problems. Certain equivalent KKT conditions of the problems are derived. Global convergence of the algorithm to a first-o... This paper presents a new trust-region algorithm for general nonlinear constrained optimization problems. Certain equivalent KKT conditions of the problems are derived. Global convergence of the algorithm to a first-order KKT point is established under mild conditions on the trial steps. Numerical example is also reported. 展开更多
关键词 nonlinear constrained optimization trust-region method global convergence.
在线阅读 下载PDF
Error bounds of Lanczos approach for trust-region subproblem
8
作者 Leihong ZHANG Weihong YANG +1 位作者 Chungen SHEN Jiang FENG 《Frontiers of Mathematics in China》 SCIE CSCD 2018年第2期459-481,共23页
Because of its vital role of the trust-region subproblem (TRS) in various applications, for example, in optimization and in ill-posed problems, there are several factorization-free algorithms for solving the large-s... Because of its vital role of the trust-region subproblem (TRS) in various applications, for example, in optimization and in ill-posed problems, there are several factorization-free algorithms for solving the large-scale sparse TRS. The truncated Lanczos approach proposed by N. I. M. Gould, S. Lucidi, M. Roma, and P. L. Toint [SIAM J. Optim., 1999, 9: 504-525] is a natural extension of the classical Lanczos method for the symmetric linear system and eigenvalue problem and, indeed follows the classical Rayleigh-Ritz procedure for eigenvalue computations. It consists of 1) projecting the original TRS to the Krylov subspa^es to yield smaller size TRS's and then 2) solving the resulted TRS's to get the approximates of the original TRS. This paper presents a posterior error bounds for both the global optimal value and the optimal solution between the original TRS and their projected counterparts. Our error bounds mainly rely on the factors from the Lanczos process as well as the data of the original TRS and, could be helpful in designing certain stopping criteria for the truncated Lanczos approach. 展开更多
关键词 trust-region method trust-region subproblem (TRS) Lanczos method Steihaug-Toint conjugate-gradient iteration error bound
原文传递
A NEW TRUST-REGION ALGORITHM FOR FINITE MINIMAX PROBLEM 被引量:2
9
作者 Fusheng Wang Chuanlong Wang Li Wang 《Journal of Computational Mathematics》 SCIE CSCD 2012年第3期262-278,共17页
In this paper, a new trust region algorithm for minimax optimization problems is proposed, which solves only one quadratic subproblem based on a new approximation model at each iteration. The approach is different wit... In this paper, a new trust region algorithm for minimax optimization problems is proposed, which solves only one quadratic subproblem based on a new approximation model at each iteration. The approach is different with the traditional algorithms that usually require to solve two quadratic subproblems. Moreover, to avoid Maratos effect, the nonmonotone strategy is employed. The analysis shows that, under standard conditions, the algorithm has global and superlinear convergence. Preliminary numerical experiments are conducted to show the effiency of the new method. 展开更多
关键词 trust-region methods Minimax optimization Nonmonotone strategy GLOBALCONVERGENCE Superlinear convergence.
原文传递
A necessary and sufficient condition of convexity for SOC reformulation of trust-region subproblem with two intersecting cuts 被引量:2
10
作者 YUAN JianHua WANG MeiLing +1 位作者 AI WenBao SHUAI TianPing 《Science China Mathematics》 SCIE CSCD 2016年第6期1127-1140,共14页
We consider the extended trust-region subproblem with two linear inequalities. In the "nonintersecting" case of this problem, Burer and Yang(2015) have proved that its semi-definite programming relaxation wi... We consider the extended trust-region subproblem with two linear inequalities. In the "nonintersecting" case of this problem, Burer and Yang(2015) have proved that its semi-definite programming relaxation with second-order-cone reformulation(SDPR-SOCR) is a tight relaxation. In the more complicated "intersecting" case, which is discussed in this paper, so far there is no result except for a counterexample for the SDPR-SOCR. We present a necessary and sufficient condition for the SDPR-SOCR to be a tight relaxation in both the "nonintersecting" and "intersecting" cases. As an application of this condition, it is verified easily that the "nonintersecting" SDPR-SOCR is a tight relaxation indeed. Furthermore, as another application of the condition, we prove that there exist at least three regions among the four regions in the trust-region ball divided by the two intersecting linear cuts, on which the SDPR-SOCR must be a tight relaxation. Finally, the results of numerical experiments show that the SDPR-SOCR can work efficiently in decreasing or even eliminating the duality gap of the nonconvex extended trust-region subproblem with two intersecting linear inequalities indeed. 展开更多
关键词 trust-region subproblem linear inequality constraints global solutions second-order-cone refor-mulation SDP relaxation
原文传递
A Subspace Version of the Powell–Yuan Trust-Region Algorithm for Equality Constrained Optimization 被引量:3
11
作者 Geovani Nunes Grapiglia Jinyun Yuan Ya-xiang Yuan 《Journal of the Operations Research Society of China》 EI 2013年第4期425-451,共27页
This paper studied subspace properties of the Celis–Dennis–Tapia(CDT)subproblem that arises in some trust-region algorithms for equality constrained optimization.The analysis is an extension of that presented by Wa... This paper studied subspace properties of the Celis–Dennis–Tapia(CDT)subproblem that arises in some trust-region algorithms for equality constrained optimization.The analysis is an extension of that presented by Wang and Yuan(Numer.Math.104:241–269,2006)for the standard trust-region subproblem.Under suitable conditions,it is shown that the trial step obtained from the CDT subproblem is in the subspace spanned by all the gradient vectors of the objective function and of the constraints computed until the current iteration.Based on this observation,a subspace version of the Powell–Yuan trust-region algorithm is proposed for equality constrained optimization problems where the number of constraints is much lower than the number of variables. The convergence analysis is given and numerical results arealso reported. 展开更多
关键词 Constrained optimization trust-region methods Subspace methods
原文传递
A trust-region and affine scaling algorithm for linearly constrained optimization 被引量:1
12
作者 陈中文 章祥荪 《Science China Mathematics》 SCIE 2002年第11期1390-1397,共8页
A new trust-region and affine scaling algorithm for linearly constrained optimization is presentedin this paper. Under no nondegenerate assumption, we prove that any limit point of the sequence generatedby the new alg... A new trust-region and affine scaling algorithm for linearly constrained optimization is presentedin this paper. Under no nondegenerate assumption, we prove that any limit point of the sequence generatedby the new algorithm satisfies the first order necessary condition and there exists at least one limit point ofthe sequence which satisfies the second order necessary condition. Some preliminary numerical experiments are reported. 展开更多
关键词 linear constraint trust-region AFFINE scaling INTERIOR point method.
原文传递
A TRUST-REGION ALGORITHM FOR NONLINEAR INEQUALITY CONSTRAINED OPTIMIZATION 被引量:1
13
作者 XiaojiaoTong ShuziZhou 《Journal of Computational Mathematics》 SCIE CSCD 2003年第2期207-220,共14页
This paper presents a new trust-region algorithm for n-dimension nonlinear optimization subject to m nonlinear inequality constraints. Equivalent KKT conditions are derived, which is the basis for constructing the new... This paper presents a new trust-region algorithm for n-dimension nonlinear optimization subject to m nonlinear inequality constraints. Equivalent KKT conditions are derived, which is the basis for constructing the new algorithm. Global convergence of the algorithm to a first-order KKT point is established under mild conditions on the trial steps, local quadratic convergence theorem is proved for nondegenerate minimizer point. Numerical experiment is presented to show the effectiveness of our approach. 展开更多
关键词 Inequality constrained optimization trust-region method Global convergence Local quadratic convergence.
原文传递
PRIMAL-DUAL PATH-FOLLOWING METHODS AND THE TRUST-REGION UPDATING STRATEGY FOR LINEAR PROGRAMMING WITH NOISY DATA 被引量:1
14
作者 Xinlong Luo Yiyan Yao 《Journal of Computational Mathematics》 SCIE CSCD 2022年第5期756-776,共21页
In this article,we consider the primal-dual path-following method and the trust-region updating strategy for the standard linear programming problem.For the rank-deficient problem with the small noisy data,we also giv... In this article,we consider the primal-dual path-following method and the trust-region updating strategy for the standard linear programming problem.For the rank-deficient problem with the small noisy data,we also give the preprocessing method based on the QR decomposition with column pivoting.Then,we prove the global convergence of the new method when the initial point is strictly primal-dual feasible.Finally,for some rankdeficient problems with or without the small noisy data from the NETLIB collection,we compare it with other two popular interior-point methods,i.e.the subroutine pathfollow.m and the built-in subroutine linprog.m of the MATLAB environment.Numerical results show that the new method is more robust than the other two methods for the rank-deficient problem with the small noise data. 展开更多
关键词 Continuation Newton method trust-region method Linear programming Rank deficiency Path-following method Noisy data.
原文传递
A New Restarting Adaptive Trust-Region Method for Unconstrained Optimization 被引量:1
15
作者 Morteza Kimiaei Susan Ghaderi 《Journal of the Operations Research Society of China》 EI CSCD 2017年第4期487-507,共21页
In this paper,we present a new adaptive trust-region method for solving nonlinear unconstrained optimization problems.More precisely,a trust-region radius based on a nonmonotone technique uses an approximation of Hes... In this paper,we present a new adaptive trust-region method for solving nonlinear unconstrained optimization problems.More precisely,a trust-region radius based on a nonmonotone technique uses an approximation of Hessian which is adaptively chosen.We produce a suitable trust-region radius;preserve the global convergence under classical assumptions to the first-order critical points;improve the practical performance of the new algorithm compared to other exiting variants.Moreover,the quadratic convergence rate is established under suitable conditions.Computational results on the CUTEst test collection of unconstrained problems are presented to show the effectiveness of the proposed algorithm compared with some exiting methods. 展开更多
关键词 Unconstrained optimization trust-region methods Nonmonotone technique Adaptive radius Theoretical convergence
原文传递
A TRUST-REGION ALGORITHM FOR SOLVING MINI-MAX PROBLEM
16
作者 Bothina E1-Sobky Abdallah Abotahoun 《Journal of Computational Mathematics》 SCIE CSCD 2018年第6期776-791,共16页
In this paper, we propose an algorithm for solving inequality constrained mini-max optimization problem. In this algorithm, an active set strategy is used together with mul- tiplier method to convert the inequality co... In this paper, we propose an algorithm for solving inequality constrained mini-max optimization problem. In this algorithm, an active set strategy is used together with mul- tiplier method to convert the inequality constrained mini-max optimization problem into unconstrained optimization problem. A trust-region method is a well-accepted technique in constrained optimization to assure global convergence and is more robust when they deal with rounding errors. One of the advantages of trust-region method is that it does not require the objective function of the model to be convex. A global convergence analysis for the proposed algorithm is presented under some conditions. To show the efficiency of the algorithm numerical results for a number of test problems are reported. 展开更多
关键词 Mini-max problem Active-set Multiplier method trust-region Global con-vergence
原文传递
A Derivative-Free Optimization Algorithm Combining Line-Search and Trust-Region Techniques
17
作者 Pengcheng XIE Ya-xiang YUAN 《Chinese Annals of Mathematics,Series B》 SCIE CSCD 2023年第5期719-734,共16页
The speeding-up and slowing-down(SUSD)direction is a novel direction,which is proved to converge to the gradient descent direction under some conditions.The authors propose the derivative-free optimization algorithm S... The speeding-up and slowing-down(SUSD)direction is a novel direction,which is proved to converge to the gradient descent direction under some conditions.The authors propose the derivative-free optimization algorithm SUSD-TR,which combines the SUSD direction based on the covariance matrix of interpolation points and the solution of the trust-region subproblem of the interpolation model function at the current iteration step.They analyze the optimization dynamics and convergence of the algorithm SUSD-TR.Details of the trial step and structure step are given.Numerical results show their algorithm’s efficiency,and the comparison indicates that SUSD-TR greatly improves the method’s performance based on the method that only goes along the SUSD direction.Their algorithm is competitive with state-of-the-art mathematical derivative-free optimization algorithms. 展开更多
关键词 Nonlinear optimization DERIVATIVE-FREE Quadratic model Line-Search trust-region
原文传递
Trust-Region Based Stochastic Variational Inference for Distributed and Asynchronous Networks
18
作者 FU Weiming QIN Jiahu +2 位作者 LING Qing KANG Yu YE Baijia 《Journal of Systems Science & Complexity》 SCIE EI CSCD 2022年第6期2062-2076,共15页
Stochastic variational inference is an efficient Bayesian inference technology for massive datasets,which approximates posteriors by using noisy gradient estimates.Traditional stochastic variational inference can only... Stochastic variational inference is an efficient Bayesian inference technology for massive datasets,which approximates posteriors by using noisy gradient estimates.Traditional stochastic variational inference can only be performed in a centralized manner,which limits its applications in a wide range of situations where data is possessed by multiple nodes.Therefore,this paper develops a novel trust-region based stochastic variational inference algorithm for a general class of conjugate-exponential models over distributed and asynchronous networks,where the global parameters are diffused over the network by using the Metropolis rule and the local parameters are updated by using the trust-region method.Besides,a simple rule is introduced to balance the transmission frequencies between neighboring nodes such that the proposed distributed algorithm can be performed in an asynchronous manner.The utility of the proposed algorithm is tested by fitting the Bernoulli model and the Gaussian model to different datasets on a synthetic network,and experimental results demonstrate its effectiveness and advantages over existing works. 展开更多
关键词 Asynchronous networks Bayesian inference distributed algorithm stochastic variational inference trust-region method
原文传递
AN ADAPTIVE TRUST-REGION METHOD FOR GENERALIZED EIGENVALUES OF SYMMETRIC TENSORS
19
作者 Yuting Chen Mingyuan Cao +1 位作者 Yueting Yang Qingdao Huang 《Journal of Computational Mathematics》 SCIE CSCD 2021年第3期358-374,共17页
For symmetric tensors,computing generalized eigenvalues is equivalent to a homogenous polynomial optimization over the unit sphere.In this paper,we present an adaptive trustregion method for generalized eigenvalues of... For symmetric tensors,computing generalized eigenvalues is equivalent to a homogenous polynomial optimization over the unit sphere.In this paper,we present an adaptive trustregion method for generalized eigenvalues of symmetric tensors.One of the features is that the trust-region radius is automatically updated by the adaptive technique to improve the algorithm performance.The other one is that a projection scheme is used to ensure the feasibility of all iteratives.Global convergence and local quadratic convergence of our algorithm are established,respectively.The preliminary numerical results show the efficiency of the proposed algorithm. 展开更多
关键词 Symmetric tensors Generalized eigenvalues trust-region Global convergence Local quadratic convergence
原文传递
A TRUST-REGION METHOD FOR NONSMOOTH NONCONVEX OPTIMIZATION
20
作者 Ziang Chen Andre Milzarek Zaiwen Wen 《Journal of Computational Mathematics》 SCIE CSCD 2023年第4期683-716,共34页
We propose a trust-region type method for a class of nonsmooth nonconvex optimization problems where the objective function is a summation of a(probably nonconvex)smooth function and a(probably nonsmooth)convex functi... We propose a trust-region type method for a class of nonsmooth nonconvex optimization problems where the objective function is a summation of a(probably nonconvex)smooth function and a(probably nonsmooth)convex function.The model function of our trust-region subproblem is always quadratic and the linear term of the model is generated using abstract descent directions.Therefore,the trust-region subproblems can be easily constructed as well as efficiently solved by cheap and standard methods.When the accuracy of the model function at the solution of the subproblem is not sufficient,we add a safeguard on the stepsizes for improving the accuracy.For a class of functions that can be“truncated”,an additional truncation step is defined and a stepsize modification strategy is designed.The overall scheme converges globally and we establish fast local convergence under suitable assumptions.In particular,using a connection with a smooth Riemannian trust-region method,we prove local quadratic convergence for partly smooth functions under a strict complementary condition.Preliminary numerical results on a family of Ei-optimization problems are reported and demonstrate the eficiency of our approach. 展开更多
关键词 trust-region method Nonsmooth composite programs Quadratic model function Global and local convergence
原文传递
上一页 1 2 46 下一页 到第
使用帮助 返回顶部