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排序方式: 共有287条查询结果,搜索用时 15 毫秒
281.
In this paper, an improved interior-type feasible QP-free algorithm for inequality constrained optimization problems is proposed. At each iteration, by solving three systems of linear equations with the same coefficient matrix, a search direction is generated. The algorithm is proved to be globally and superlinearly convergent under some mild conditions. Preliminary numerical results show that the proposed algorithm may be promising. Advantages of the algorithm include: the uniformly nonsingularity of the coefficient matrices without the strictly complementarity condition is obtained. Moreover, the global convergence is achieved even if the number of the stationary points is infinite. 相似文献
282.
In this paper, an improved feasible QP-free method is proposed to solve nonlinear inequality constrained optimization problems. Here, a new modified method is presented to obtain the revised feasible descent direction. In view of the computational cost, the most attractive feature of the new algorithm is that only one system of linear equations is required to obtain the revised feasible descent direction. Thereby, per single iteration, it is only necessary to solve three systems of linear equations with the same coefficient matrix. In particular, without the positive definiteness assumption on the Hessian estimate, the proposed algorithm is still global convergence. Under some suitable conditions, the superlinear convergence rate is obtained. 相似文献
283.
利用微分学方法给出刘徽不等式与祖冲之不等式的证明;得到两个关于双曲函数的不等式;还得到两个关于单位圆内接正n边形周长与π之间关系的不等式. 相似文献
284.
Let be the Kaplan-Meier estimator of distribution function F. Let J(˙) be a measurable real-valued function. In this paper, a U-statistic representation for the Kaplan-Meier L-estimator, , is derived. Furthermore, the representation is also used to establish a Berry-Essen inequality for .
Received September 28, 1998, Accepted March 10, 1999 相似文献
285.
A technical framework of constructing a linear controller for
chaotic synchronization by utilizing the stability theory of
cascade-connected system is presented. Based on the method developed
in the paper, two simple and linear feedback controllers, as
examples, are derived for the synchronization of Liu chaotic system
and Duffing oscillator, respectively. This method is quite flexible
in constructing a control law. Its effectiveness is also illustrated
by the simulation results. 相似文献
286.
Lagrangian methods are popular in solving continuous constrained optimization problems. In this paper, we address three important issues in applying Lagrangian methods to solve optimization problems with inequality constraints.First, we study methods to transform inequality constraints into equality constraints. An existing method, called the slack-variable method, adds a slack variable to each inequality constraint in order to transform it into an equality constraint. Its disadvantage is that when the search trajectory is inside a feasible region, some satisfied constraints may still pose some effect on the Lagrangian function, leading to possible oscillations and divergence when a local minimum lies on the boundary of the feasible region. To overcome this problem, we propose the MaxQ method that carries no effect on satisfied constraints. Hence, minimizing the Lagrangian function in a feasible region always leads to a local minimum of the objective function. We also study some strategies to speed up its convergence.Second, we study methods to improve the convergence speed of Lagrangian methods without affecting the solution quality. This is done by an adaptive-control strategy that dynamically adjusts the relative weights between the objective and the Lagrangian part, leading to better balance between the two and faster convergence.Third, we study a trace-based method to pull the search trajectory from one saddle point to another in a continuous fashion without restarts. This overcomes one of the problems in existing Lagrangian methods that converges only to one saddle point and requires random restarts to look for new saddle points, often missing good saddle points in the vicinity of saddle points already found.Finally, we describe a prototype Novel (Nonlinear Optimization via External Lead) that implements our proposed strategies and present improved solutions in solving a collection of benchmarks. 相似文献
287.
一类对称函数不等式的加细和推广 总被引:8,自引:1,他引:7
石焕南 《数学的实践与认识》1999,29(4):81-84
利用控制不等式理论加细和推广了一类对称函数不等式,并给出一个几何应用。 相似文献