Derivative-free methods (Conjugate Gradient Methods) for dealing with nonlinear equations and image restoration
摘要
The conjugate gradient methods (CGs) have successfully solved large-scale unconstrained minimization problems. However, research activities on the methods (CGs) for some other applications are somewhat fewer. In this paper, we propose new parameters for designing two new methods as extensions and developments of the classical methods (CGs). We supply these proposed methods with a proper step size and line search technique that depends on backtracking line search to make both proposed methods capable of dealing with pretty complicated nonlinear systems. If the size of the system is very large, the task is more challenging for dealing with such a system. The two proposed methods (CGs), therefore, in this paper are abbreviated by FCGNE and HMHZS. The FCGNE method contains two new parameters of the CG method with a convexity coefficient that combines the two parameters to get a research direction. The HMHZS method is a new hybrid CG method that hybridizes three old methods (CGs) to obtain a new research direction. One task of this study is to establish the global convergence proof of the FCGNE approach by presenting some limited conditions. The effectiveness of the suggested algorithms is tested by solving a group of systems of nonlinear equations involving