Nonlinear Optimization

A Derivative-Free Algorithm for Constrained Global Optimization based on Exact Penalty Functions

  • G. Di Pillo
  • Stefano Lucidi
  • Francesco Rinaldi
    • Categories Global Optimization, Nonlinear Optimization

    Constrained global optimization problems can be tackled by using exact penalty approaches. In a preceding paper, we proposed an exact penalty algorithm for constrained problems which combines an unconstrained global minimization technique for minimizing a non-differentiable exact penalty func- tion for given values of the penalty parameter, and an automatic updating of the penalty parameter … Read more

    Derivative-free Robust Optimization for Circuit Design

  • A. Ciccazzo
  • Giampaolo Liuzzi
  • Stefano Lucidi
  • Francesco Rinaldi
  • V. Latorre
    • Categories Nonlinear Optimization, Robust Optimization Tags

    In this paper, we introduce a framework for derivative-free robust optimization based on the use of an efficient derivative-free optimization routine for mixed integer nonlinear problems. The proposed framework is employed to find a robust optimal design of a particular integrated circuit (namely a DC-DC converter commonly used in portable electronic devices). The proposed robust … Read more

    A Parallel Quadratic Programming Method for Dynamic Optimization Problems

  • Moritz Diehl
  • Sebastian Sager
  • Janick V Frasch
    • Categories Control Applications, Quadratic Programming Tags , , ,

    Quadratic programming problems (QPs) that arise from dynamic optimization problems typically exhibit a very particular structure. We address the ubiquitous case where these QPs are strictly convex and propose a dual Newton strategy that exploits the block-bandedness similarly to an interior-point method. Still, the proposed method features warmstarting capabilities of active-set methods. We give details … Read more

    An alternative proof of a PTAS for fixed-degree polynomial optimization over the simplex

  • Etienne de Klerk
  • Monique Laurent
  • Zhao Sun
    • Categories Nonlinear Optimization Tags , ,

    The problem of minimizing a polynomial over the standard simplex is one of the basic NP-hard nonlinear optimization problems — it contains the maximum clique problem in graphs as a special case. It is known that the problem allows a polynomial-time approximation scheme (PTAS) for polynomials of fixed degree, which is based on polynomial evaluations … Read more

    Finding Diverse Solutions of High Quality to Binary Integer Programs

  • Renata A. Konrad
  • Andrew C. Trapp
    • Categories 0-1 Programming, Multi-Criteria Optimization, Nonlinear Optimization

    Typical output from an optimization solver is a single optimal solution. At the same time, a set of high-quality and diverse solutions could be beneficial in a variety of contexts, for example problems involving imperfect information, or those for which the structure of high-quality solution vectors can reveal meaningful insights. In view of this, we … Read more

    A Regularized SQP Method with Convergence to Second-Order Optimal Points

  • Philip E. Gill
  • Vyacheslav Kungurtsev
  • Daniel P. Robinson
    • Categories Constrained Nonlinear Optimization, Nonlinear Optimization Tags , , , , , ,

    Regularized and stabilized sequential quadratic programming methods are two classes of sequential quadratic programming (SQP) methods designed to resolve the numerical and theoretical difficulties associated with ill-posed or degenerate nonlinear optimization problems. Recently, a regularized SQP method has been proposed that provides a strong connection between augmented Lagrangian methods and stabilized SQP methods. The method … Read more

    An efficient gradient method using the Yuan steplength

  • Roberta De Asmundis
  • Daniela di Serafino
  • William W. Hager
  • Gerardo Toraldo
  • Hongchao Zhang
    • Categories Nonlinear Optimization, Quadratic Programming, Unconstrained Optimization Tags , ,

    We propose a new gradient method for quadratic programming, named SDC, which alternates some SD iterates with some gradient iterates that use a constant steplength computed through the Yuan formula. The SDC method exploits the asymptotic spectral behaviour of the Yuan steplength to foster a selective elimination of the components of the gradient along the … Read more

    A feasible active set method for strictly convex problems with simple bounds

  • Philipp Hungerländer
  • Franz Rendl
    • Categories Convex Optimization, Quadratic Programming Tags , , ,

    A primal-dual active set method for quadratic problems with bound constraints is presented which extends the infeasible active set approach of [K. Kunisch and F. Rendl. An infeasible active set method for convex problems with simple bounds. SIAM Journal on Optimization, 14(1):35-52, 2003]. Based on a guess of the active set, a primal-dual pair (x,α) … Read more

    Quasi-Newton updates with weighted secant equations

  • Serge Gratton
  • Vincent Malmedy
  • Philippe L. Toint
    • Categories Nonlinear Systems and Least-Squares, Unconstrained Optimization Tags , ,

    We provide a formula for variational quasi-Newton updates with multiple weighted secant equations. The derivation of the formula leads to a Sylvester equation in the correction matrix. Examples are given. Citation Report naXys-09-2013, Namur Centre for Complex Systems, Unibersity of Namur, Namur (Belgium) Article Download View Quasi-Newton updates with weighted secant equations

    An Active-Set Quadratic Programming Method Based On Sequential Hot-Starts

  • Travis C. Johnson
  • Christian Kirches
  • Andreas Wächter
    • Categories Quadratic Programming Tags , , , , , , ,

    A new method for solving sequences of quadratic programs (QPs) is presented. For each new QP in the sequence, the method utilizes hot-starts that employ information computed by an active-set QP solver during the solution of the first QP. This avoids the computation and factorization of the full matrices for all but the first problem … Read more