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1.
A revised conjugate gradient projection method for nonlinear inequality constrained optimization problems is proposed in the paper, since the search direction is the combination of the conjugate projection gradient and the quasi-Newton direction. It has two merits. The one is that the amount of computation is lower because the gradient matrix only needs to be computed one time at each iteration. The other is that the algorithm is of global convergence and locally superlinear convergence without strict complementary condition under some mild assumptions. In addition the search direction is explicit.  相似文献   

2.
In this paper we consider the global convergence of any conjugate gradient method of the form d1=-g1,dk+1=-gk+1+βkdk(k≥1)with any βk satisfying sume conditions,and with the strong wolfe line search conditions.Under the convex assumption on the objective function,we preve the descenf property and the global convergence of this method.  相似文献   

3.
In this paper, a modified formula for βk^PRP is proposed for the conjugate gradient method of solving unconstrained optimization problems. The value of βk^PRP keeps nonnegative independent of the line search. Under mild conditions, the global convergence of modified PRP method with the strong Wolfe-Powell line search is established. Preliminary numerical results show that the modified method is efficient.  相似文献   

4.
A NOTE ON THE NONLINEAR CONJUGATE GRADIENT METHOD   总被引:2,自引:0,他引:2  
The conjugate gradient method for unconstrained optimization problems varies with a scalar. In this note, a general condition concerning the scalar is given, which ensures the global convergence of the method in the case of strong Wolfe line searches. It is also discussed how to use the result to obtain the convergence of the famous Fletcher-Reeves, and Polak-Ribiere-Polyak conjugate gradient methods. That the condition cannot be relaxed in some sense is mentioned.  相似文献   

5.
This paper discusses the global convergence of a class of nonmonotone conjugate gradient methods (NM methods) for nonconvex object functions. This class of methods includes the nonmonotone counterpart of modified Polak-Ribiere method and modified Hestenes-Stiefel method as special cases.  相似文献   

6.
In this note,by combining the nice numerical performance of PR and HS methods with the global convergence property of FR method,a class of new restarting three terms conjugate gradient methods is presented.Global convergence properties of the new method with two kinds of common line searches are proved.  相似文献   

7.
In this paper we propose an affine scaling interior algorithm via conjugate gradient path for solving nonlinear equality systems subject to bounds on variables. By employing the affine scaling conjugate gradient path search strategy, we obtain an iterative direction by solving the linearize model. By using the line search technique, we will find an acceptable trial step length along this direction which is strictly feasible and makes the objective func- tion nonmonotonically decreasing. The global convergence and fast local convergence rate of the proposed algorithm are established under some reasonable conditions. Furthermore, the numerical results of the proposed algorithm indicate to be effective.  相似文献   

8.
In this paper, we give the convergence and consistence theory of multiple search direction conjugate gradient method (see [10]) and give some upper bound estimations of iterative value and error of our method.  相似文献   

9.
Conjugate Gradient Methods with Armijo-type Line Searches   总被引:14,自引:0,他引:14  
Abstract Two Armijo-type line searches are proposed in this paper for nonlinear conjugate gradient methods.Under these line searches, global convergence results are established for several famous conjugate gradientmethods, including the Fletcher-Reeves method, the Polak-Ribiere-Polyak method, and the conjugate descentmethod.  相似文献   

10.
Abstract. The global convergence of the general three-term conjugate gradient methods withthe relaxed strong Wolfe line-search is proved.  相似文献   

11.
In this paper, we propose a new trust-region-projected Hessian algorithm with nonmonotonic backtracking interior point technique for linear constrained optimization. By performing the QR decomposition of an affine scaling equality constraint matrix, the conducted subproblem in the algorithm is changed into the general trust-region subproblem defined by minimizing a quadratic function subject only to an ellipsoidal constraint. By using both the trust-region strategy and the line-search technique, each iteration switches to a backtracking interior point step generated by the trustregion subproblem. The global convergence and fast local convergence rates for the proposed algorithm are established under some reasonable assumptions. A nonmonotonic criterion is used to speed up the convergence in some ill-conditioned cases. Selected from Journal of Shanghai Normal University (Natural Science), 2003, 32(4): 7–13  相似文献   

12.
We prove the superlinear convergence of a nonmonotone BFGS algorithm on convex objective functions under suitable conditions.  相似文献   

13.
The objective of this article is to establish an oscillation criterion for all solutions of nonlinear difference equation where r(η) $$ r\left(\eta \right) $$ is a sequence of nonnegative real numbers and φ(η) $$ \varphi \left(\eta \right) $$ is not necessarily monotone sequence. Also, an example is presented to illustrate the significance of the main result.  相似文献   

14.
The paper deals with approximations and the numerical realization of a class of hemivariational inequalities used for modeling of delamination and nonmonotone friction problems. Assumptions guaranteeing convergence of discrete models are verified and numerical results of several model examples computed by a nonsmooth variant of Newton method are presented.The research was realized in the frame of the bilateral cooperation between Charles University, Prague and Aristotle University, Thessaloniki. The second author also acknowledges the support of the grant no. IAA1075402 of the Grant Agency of the Academy of Sciences of the Czech Republic and MSM 113200007.This revised version was published online in April 2005 with a corrected issue number.  相似文献   

15.
16.
We consider a general equilibrium problem defined on a convex set, whose cost bifunction may not be monotone. We show that this problem can be solved by the inexact proximal point method if there exists a solution to the dual problem. An application of this approach to nonlinearly constrained problems is also suggested.  相似文献   

17.
一个求解非线性对称方程组的非单调信赖域方法   总被引:2,自引:0,他引:2  
  相似文献   

18.
一类约束优化问题的非单调信赖域算法   总被引:1,自引:0,他引:1  
本文就一类等式约束优化问题,结合当前比较流行的非单调技术,提出了一类新的求解等式约束优化的非单调信赖域算法.其非单调程度由算法自适应控制,计算预测下降量和实际下降量的比值时,采用前m(k)个点的信息,这不同于以前在计算预测下降量和实际下降量的比值时,仅仅采用当前-个点的信息.在没有正则性条件的假设下我们证明了算法是有定义的.并且通过对不同情况的讨论证明了算法的全局收敛性.基本的数值试验表明算法是有效的,且说明提出的非单调信赖域算法比单调信赖域算法有效.  相似文献   

19.
研究了非协调有限元逼近非单调型拟线性椭圆问题,使用超收敛误差估计技巧,得出该问题光滑解和有限元解之间存在的超收敛关系.  相似文献   

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