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1.
提出了一类新的求解无约束最优化问题的新拟牛顿非单调信赖域算法.采用加权的r_k用以调整信赖域半径,在适当的条件下,证明了算法的全局收敛性.数值结果表明算法的有效性.  相似文献   

2.
一类带非单调线搜索的信赖域算法   总被引:1,自引:0,他引:1  
通过将非单调Wolfe线搜索技术与传统的信赖域算法相结合,我们提出了一类新的求解无约束最优化问题的信赖域算法.新算法在每一迭代步只需求解一次信赖域子问题,而且在每一迭代步Hesse阵的近似都满足拟牛顿条件并保持正定传递.在一定条件下,证明了算法的全局收敛性和强收敛性.数值试验表明新算法继承了非单调技术的优点,对于求解某...  相似文献   

3.
一类带线搜索的非单调信赖域算法   总被引:15,自引:0,他引:15  
本文对于无约束最优化问题提出了一类新的非单调信赖域算法.与通常的非单调信赖域算法不同,当试探步不成功时,并不重解信赖域子问题,而采用非单调线搜索,从而减小了计算量.在适当的条件下,证明了此算法的全局收敛性.  相似文献   

4.
一类新的非单调信赖域算法及其收敛性   总被引:19,自引:0,他引:19  
利用非单调性,邓乃扬等提出了一类具有强收敛性质的非单调信赖型算法,为了保证算法的收敛性,他们假定以下两个条件成立;(1)信赖域半径(△k)有上界;(2)对所有k有∥sk∥≤c∥gk∥,其中sk=xk+1-xk,gk为f(t)在xk处的梯度,c〉0随后,柯小伍,韩继业从另一角度了提出了一类非调信赖域型算法,尽管他们未利用条件,但仍假定条件(2)成立,在本文中,我们提出了一类新的非单调信赖域算法,在没  相似文献   

5.
无约束最优化的一类非单调信赖域算法   总被引:1,自引:0,他引:1       下载免费PDF全文
提出无约束最优化的一类非单调信赖域算法 .在适当的条件下 ,证明此算法的全局和Q 二次收敛性 ,还讨论了步长和信赖域半径的几种选取规则 .  相似文献   

6.
一类新的信赖域算法的全局收敛性   总被引:22,自引:1,他引:22  
本文对于无约束最优化问题提出了一类非单调的信赖域算法,它是通常的单调信赖域算法的推广。当目标函数是有下界的连续可微函数,而且它的二阶导数的近似的模是线性地依赖于迭代次数时,我们证明了新算法的整体收敛性。  相似文献   

7.
刘亚君  刘新为 《计算数学》2016,38(1):96-112
梯度法是求解无约束最优化的一类重要方法.步长选取的好坏与梯度法的数值表现息息相关.注意到BB步长隐含了目标函数的二阶信息,本文将BB法与信赖域方法相结合,利用BB步长的倒数去近似目标函数的Hesse矩阵,同时利用信赖域子问题更加灵活地选取梯度法的步长,给出求解无约束最优化问题的单调和非单调信赖域BB法.在适当的假设条件下,证明了算法的全局收敛性.数值试验表明,与已有的求解无约束优化问题的BB类型的方法相比,非单调信赖域BB法中e_k=‖x_k-x~*‖的下降呈现更明显的阶梯状和单调性,因此收敛速度更快.  相似文献   

8.
本文对无约束优化问题提出了一类基于锥模型的非单调信赖域算法.二次模型非单调信赖域算法是新算法的特例.在适当的条件下,证明了算法的全局收敛性及Q-二次收敛性.  相似文献   

9.
无约束多目标规划的非单调信赖域算法   总被引:1,自引:0,他引:1  
本提出了无约束多目标规划的一类非单调信赖域算法,并证明了算法的全局收敛性。  相似文献   

10.
一类新的非单调信赖域算法   总被引:1,自引:0,他引:1  
提出了一类带线性搜索的非单调信赖域算法.算法将非单调Armijo线性搜索技术与信赖域方法相结合,使算法不需重解子问题.而且由于采用了MBFGS校正公式,使矩阵Bk能较好地逼近目标函数的Hesse矩阵并保持正定传递.在较弱的条件下,证明了算法的全局收敛性.数值结果表明算法是有效的.  相似文献   

11.
This paper presents a new trust region algorithm for solving a class of composite nonsmooth optimizations. It is distinguished by the fact that this method does not enforce strict monotonicity of the objective function values at successive iterates and that this method extends the existing results for this type of nonlinear optimization with smooth, or piecewise smooth, or convex objective functions or their composition. It is proved that this algorithm is globally convergent under certain conditions. Finally, some numerical results for several optimization problems are reported which show that the nonmonotonic trust region method is competitive with the usual trust region method.  相似文献   

12.
§1 IntroductionIn this paper we analyze an interior point scaling projected reduced Hessian methodwith trust region strategy for solving the nonlinear equality constrained optimizationproblem with nonnegative constraints on variables:min f(x)s.t. c(x) =0 (1.1)x≥0where f∶Rn→R is the smooth nonlinear function,notnecessarily convex and c(x)∶Rn→Rm(m≤n) is the vector nonlinear function.There are quite a few articles proposing localsequential quadratic programming reduced Hessian methods…  相似文献   

13.
本文利用函数平均权重的非单调技术以及自适应信赖域方法,提出一个解非线性方程组的非单调自适应信赖域法.并在适当假设条件下,讨论了算法的全局收敛性.数值试验表明了算法是有效的.  相似文献   

14.
We extend the classical affine scaling interior trust region algorithm for the linear constrained smooth minimization problem to the nonsmooth case where the gradient of objective function is only locally Lipschitzian. We propose and analyze a new affine scaling trust-region method in association with nonmonotonic interior backtracking line search technique for solving the linear constrained LC1 optimization where the second-order derivative of the objective function is explicitly required to be locally Lipschitzian. The general trust region subproblem in the proposed algorithm is defined by minimizing an augmented affine scaling quadratic model which requires both first and second order information of the objective function subject only to an affine scaling ellipsoidal constraint in a null subspace of the augmented equality constraints. The global convergence and fast local convergence rate of the proposed algorithm are established under some reasonable conditions where twice smoothness of the objective function is not required. Applications of the algorithm to some nonsmooth optimization problems are discussed.  相似文献   

15.
Nonmonotonic trust region algorithm   总被引:24,自引:0,他引:24  
A nonmonotonic trust region method for unconstrained optimization problems is presented. Although the method allows the sequence of values of the objective function to be nonmonotonic, convergence properties similar to those for the usual trust region method are proved under certain conditions, including conditions on the approximate solutions to the subproblem. To make the solution satisfy these conditions, an algorithm to solve the subproblem is also established. Finally, some numerical results are reported which show that the nonmonotonic trust region method is superior to the usual trust region method according to both the number of gradient evaluations and the number of function evaluations.The authors would like to thank Professor L. C. W. Dixon for his useful suggestions.  相似文献   

16.
In this paper,on the basis of making full use of the characteristics of unconstrained generalized geometric programming(GGP),we establish a nonmonotonic trust region algorithm via the conjugate path for solving unconstrained GGP problem.A new type of condensation problem is presented,then a particular conjugate path is constructed for the problem,along which we get the approximate solution of the problem by nonmonotonic trust region algorithm,and further prove that the algorithm has global convergence and quadratic convergence properties.  相似文献   

17.
欧宜贵  侯定丕 《东北数学》2002,18(4):335-342
This paper preasents a new trust region algorithm for solving a class of composite nonsmooth optimizations.It is distinguished by the fact that this method does not enforce strict monotonicity of the objective function values at successive itereates and that this method extends the existing results for this type of nonlinear optimization with smooth ,or piecewis somooth,or convex objective functions or their composition It is pyoved that this algorithm is globally convergent under certain conditions.Finally,some numerical results for several optimization problems are reported which show that the nonmonotonic trust region method is competitive with the usual trust region method.  相似文献   

18.
In this paper, we propose a new nonmonotonic interior point backtracking strategy to modify the reduced projective affine scaling trust region algorithm for solving optimization subject to nonlinear equality and linear inequality constraints. The general full trust region subproblem for solving the nonlinear equality and linear inequality constrained optimization is decomposed to a pair of trust region subproblems in horizontal and vertical subspaces of linearize equality constraints and extended affine scaling equality constraints. The horizontal subproblem in the proposed algorithm is defined by minimizing a quadratic projective reduced Hessian function subject only to an ellipsoidal trust region constraint in a null subspace of the tangential space, while the vertical subproblem is also defined by the least squares subproblem subject only to an ellipsoidal trust region constraint. By introducing the Fletcher's penalty function as the merit function, trust region strategy with interior point backtracking technique will switch to strictly feasible interior point step generated by a component direction of the two trust region subproblems. The global convergence of the proposed algorithm while maintaining fast local convergence rate of the proposed algorithm are established under some reasonable conditions. A nonmonotonic criterion should bring about speeding up the convergence progress in some high nonlinear function conditioned cases.  相似文献   

19.
本文提供修正近似信赖域类型路经三类预条件弧线路径方法解无约束最优化问题.使用对称矩阵的稳定Bunch-Parlett易于形成信赖域子问题的弧线路径,使用单位下三角矩阵作为最优路径和修正梯度路径的预条件因子.运用预条件因子改进Hessian矩阵特征值分布加速预条件共轭梯度路径收敛速度.基于沿着三类路径信赖域子问题产生试探步,将信赖域策略与非单调线搜索技术相结合作为新的回代步.理论分析证明在合理条件下所提供的算法是整体收敛性,并且具有局部超线性收敛速率,数值结果表明算法的有效性.  相似文献   

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