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1.
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   

2.
凸约束优化的非单调信赖域算法的收敛性   总被引:1,自引:0,他引:1  
本文对凸约束优化问题提出一类新的非单调信赖域算法,在二次模型Hesse矩阵{Bk}一致有界条件下,证明了算法具有强收敛性;在{Bk}线性增长的条件下,证明了算法具有弱收敛性;这推广了现有约束或凸约束优化问题的各种信赖域算法,改进了收敛性结果。  相似文献   

3.
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   

4.
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   

5.
一种基于新锥模型的自适应信赖域算法   总被引:1,自引:0,他引:1  
本文提出一种自动确定信赖域半径的新锥模型信赖域算法.该算法在每步迭代中利用以前迭代点的二次信息和水平向量信息自动产生一个信赖域半径.且证明了全局收敛性及超线性收敛性,数值结果验证了新算法的有效性.  相似文献   

6.
文章结合非单调信赖域方法和非单调线搜索技术提出了一类新的无约束优化算法.与传统的非单调信赖与算法相比,此算法在每步都采用非单调Wolfe线搜索得到下一个迭代点,信赖域半径由子问题的近似解和线搜索的步长调节,这样得到的新算法不仅不需重解子问题,而且在每步迭代保证目标函数的近似海赛矩阵的正定性,在一定条件下证明了算法具有全局收敛性和Q-二次收敛性.数值试验表明算法是十分有效的.  相似文献   

7.
本文对线性约束多规划问题提出了一类非单调信赖域算法 ,该方法是可行点法与信赖域技巧的结合 .在一定的条件下证明了算法的全局收敛性 .并进行了数值试验 .  相似文献   

8.
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   

9.
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   

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.
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 from 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 efficiency of the new method.  相似文献   

12.
A class of nonmonotone trust region algorithms is presented for unconstrained optimizations. Under suitable conditions, the global and Q-quadratic convergences of the algorithm are proved. Several rules of choosing trial steps and trust region radii are also discussed. Project supported by the National Natural Science Foundation of China (Grant No. 19136012).  相似文献   

13.
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   

14.
In this paper, we present a nonmonotone filter trust region algorithm for solving nonlinear equality constrained optimization. Similar to Bryd–Omojokun class of algorithms, each step is composed of a quasi-normal step and a tangential step. This new method has more flexibility for the acceptance of the trial step compared to the filter methods, and requires less computational costs compared with the monotone methods. Under reasonable conditions, we give the globally convergence properties. Numerical tests are presented that confirm the efficiency of the approach.  相似文献   

15.
Two trust regions algorithms for unconstrained nonlinear optimization problems are presented: a monotone and a nonmonotone one. Both of them solve the trust region subproblem by the spectral projected gradient (SPG) method proposed by Birgin, Martínez and Raydan (in SIAM J. Optim. 10(4):1196?C1211, 2000). SPG is a nonmonotone projected gradient algorithm for solving large-scale convex-constrained optimization problems. It combines the classical projected gradient method with the spectral gradient choice of steplength and a nonmonotone line search strategy. The simplicity (only requires matrix-vector products, and one projection per iteration) and rapid convergence of this scheme fits nicely with globalization techniques based on the trust region philosophy, for large-scale problems. In the nonmonotone algorithm the trial step is evaluated by acceptance via a rule which can be considered a generalization of the well known fraction of Cauchy decrease condition and a generalization of the nonmonotone line search proposed by Grippo, Lampariello and Lucidi (in SIAM J. Numer. Anal. 23:707?C716, 1986). Convergence properties and extensive numerical results are presented. Our results establish the robustness and efficiency of the new algorithms.  相似文献   

16.
万中  冯冬冬 《计算数学》2011,33(4):387-396
基于非单调线搜索在寻求优化问题最优解中的优越性,提出了一类新的非单调保守BFGS算法.同已有方法不同,该算法中用来控制非单调性程度的算法参数不是取固定值,而是利用已有目标函数和梯度函数的信息自动调整其取值,以改善算法的数值表现.在合适的假设条件下,建立了新的非单调保守BFGS算法的全局收敛性.用基准测试优化问题测试了算...  相似文献   

17.
In this paper we propose new globalization strategies for the Barzilai and Borwein gradient method, based on suitable relaxations of the monotonicity requirements. In particular, we define a class of algorithms that combine nonmonotone watchdog techniques with nonmonotone linesearch rules and we prove the global convergence of these schemes. Then we perform an extensive computational study, which shows the effectiveness of the proposed approach in the solution of large dimensional unconstrained optimization problems.  相似文献   

18.
The trust region(TR) method for optimization is a class of effective methods.The conic model can be regarded as a generalized quadratic model and it possesses the good convergence properties of the quadratic model near the minimizer.The Barzilai and Borwein(BB) gradient method is also an effective method,it can be used for solving large scale optimization problems to avoid the expensive computation and storage of matrices.In addition,the BB stepsize is easy to determine without large computational efforts.In this paper,based on the conic trust region framework,we employ the generalized BB stepsize,and propose a new nonmonotone adaptive trust region method based on simple conic model for large scale unconstrained optimization.Unlike traditional conic model,the Hessian approximation is an scalar matrix based on the generalized BB stepsize,which resulting a simple conic model.By adding the nonmonotone technique and adaptive technique to the simple conic model,the new method needs less storage location and converges faster.The global convergence of the algorithm is established under certain conditions.Numerical results indicate that the new method is effective and attractive for large scale unconstrained optimization problems.  相似文献   

19.
We propose a nonmonotone adaptive trust region method based on simple conic model for unconstrained optimization. Unlike traditional trust region methods, the subproblem in our method is a simple conic model, where the Hessian of the objective function is approximated by a scalar matrix. The trust region radius is adjusted with a new self-adaptive adjustment strategy which makes use of the information of the previous iteration and current iteration. The new method needs less memory and computational efforts. The global convergence and Q-superlinear convergence of the algorithm are established under the mild conditions. Numerical results on a series of standard test problems are reported to show that the new method is effective and attractive for large scale unconstrained optimization problems.  相似文献   

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