Estimation and Variational Methods for Gradient Algorithm Generation

نویسنده

  • Paul Michel
چکیده

This study containsa new approach to the unconstrained minimization of a multivariable function f(.) using a quasi-Newton step computation procedure. The whole problem is reformulated as the control problem of a linear system described by its state-space equations and having unknown dynamical properties. First of all, an adaptive identification problem arises and is solved by using set estimation concepts. The resulting dynamics contain in particular an-estimate of the Hessian matrix of f(x), matrix which is used to regulate the system to zero. Some matrix symmetrization methods are also studied and finally used for generating a sequence of steps ~+lx k by the classical Newton method. THESIS SUPERVISOR: Sanjoy K. Mitter TITLE: Professor of Electrical Engineering and ComputerScience

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تاریخ انتشار 2012