Complementarity and Variational Inequalities

Complementarity-Based Nonlinear Programming Techniques for Optimal Mixing in Gas Networks

  • Falk M. Hante
  • Martin Schmidt
    • Categories Applications - Science and Engineering, Complementarity and Variational Inequalities, Nonlinear Optimization Tags , , , ,

    We consider nonlinear and nonsmooth mixing aspects in gas transport optimization problems. As mixed-integer reformulations of pooling-type mixing models already render small-size instances computationally intractable, we investigate the applicability of smooth nonlinear programming techniques for equivalent complementarity-based reformulations. Based on recent results for remodeling piecewise affine constraints using an inverse parametric quadratic programming approach, we … Read more

    Two New Weak Constraint Qualifications for Mathematical Programs with Equilibrium Constraints and Applications

  • Alberto Ramos
    • Categories Complementarity and Variational Inequalities, Constrained Nonlinear Optimization Tags ,

    We introduce two new weaker Constraint Qualifications (CQs) for Mathematical Programs with Equilibrium (or Complementarity) Constraints, MPEC for short. One of them is a tailored version of the Constant Rank of Subspace Component (CRSC) and the other is a relaxed version of the MPEC-No Nonzero Abnormal Multiplier Constraint Qualification (MPEC-NNAMCQ). Both incorporate the exact set … Read more

    The New Butterfly Relaxation Methods for Mathematical Program with Complementarity Constraints

  • Jean-Pierre Dussault
  • Tangi Migot
  • Mounir Haddou
    • Categories Complementarity and Variational Inequalities, Constrained Nonlinear Optimization Tags

    We propose a new family of relaxation schemes for mathematical program with complementarity constraints that extends the relaxations of Kadrani, Dussault, Bechakroun from 2009 and the one of Kanzow \& Schwartz from 2011. We discuss the properties of the sequence of relaxed non-linear program as well as stationarity properties of limiting points. A sub-family of … Read more

    How to Compute a M-stationary point of the MPCC

  • Jean-Pierre Dussault
  • Tangi Migot
  • Mounir Haddou
  • Abdeslam Kadrani
    • Categories Complementarity and Variational Inequalities, Constrained Nonlinear Optimization

    We discuss here the convergence of relaxation methods for MPCC with approximate sequence of stationary points by presenting a general framework to study these methods. It has been pointed out in the literature, \cite{kanzow2015}, that relaxation methods with approximate stationary points fail to give guarantee of convergence. We show that by defining a new strong … Read more

    Several variants of the primal-dual hybrid gradient algorithm with applications

  • Jianchao Bai
  • Jicheng Li
  • Zhie Wu
    • Categories Complementarity and Variational Inequalities, Convex Optimization

    By reviewing the primal-dual hybrid algorithm (PDHA) proposed by He, You and Yuan (SIAM J. Imaging Sci. 2014;7(4):2526-2537), in this paper we introduce four improved schemes for solving a class of generalized saddle-point problems. By making use of the variational inequality, weaker conditions are presented to ensure the global convergence of the proposed algorithms, where … Read more

    Weakly homogeneous variational inequalities and solvability of nonlinear equations over cones

  • M. Seetharama Gowda
  • D. Sossa
    • Categories Complementarity and Variational Inequalities Tags , , , ,

    Given a closed convex cone C in a finite dimensional real Hilbert space H, a weakly homogeneous map f:C–>H is a sum of two continuous maps h and g, where h is positively homogeneous of (positive) degree gamma on C and g(x)/||x||^gamma–>0 as ||x||–>infinity in C. Given such a map f, a nonempty closed convex … Read more

    Convergence properties of a second order augmented Lagrangian method for mathematical programs with complementarity constraints

  • Roberto Andreani
  • Paulo J. S. Silva
  • Leonardo D. Secchin
    • Categories Complementarity and Variational Inequalities Tags , ,

    Mathematical Programs with Complementarity Constraints (MPCCs) are difficult optimization problems that do not satisfy the majority of the usual constraint qualifications (CQs) for standard nonlinear optimization. Despite this fact, classical methods behaves well when applied to MPCCs. Recently, Izmailov, Solodov and Uskov proved that first order augmented Lagrangian methods, under a natural adaption of the … Read more

    Symmetric ADMM with Positive-Indefinite Proximal Regularization for Linearly Constrained Convex Optimization

  • Bin Gao
  • Feng Ma
    • Categories Complementarity and Variational Inequalities, Convex Optimization, Parallel Algorithms Tags , , ,

    The proximal ADMM which adds proximal regularizations to ADMM’s subproblems is a popular and useful method for linearly constrained separable convex problems, especially its linearized case. A well-known requirement on guaranteeing the convergence of the method in the literature is that the proximal regularization must be positive semidefinite. Recently it was shown by He et … Read more

    Lyapunov rank of polyhedral positive operators

  • Michael Orlitzky
    • Categories Complementarity and Variational Inequalities, Convex Optimization, Linear, Cone and Semidefinite Programming Tags , , , ,

    If K is a closed convex cone and if L is a linear operator having L(K) a subset of K, then L is a positive operator on K and L preserves inequality with respect to K. The set of all positive operators on K is denoted by pi(K). If J is the dual of K, … Read more

    Differentiated oligopolistic markets with concave cost functions via Ky Fan inequalities

  • Giancarlo Bigi
  • Mauro Passacantando
    • Categories Complementarity and Variational Inequalities, Finance and Economics Tags , , , ,

    A model for Nash-Cournot oligopolistic markets with concave cost functions and a differentiated commodity is analysed. Equilibrium states are characterized through Ky Fan inequalities. Relying on the minimization of a suitable merit function, a general algorithmic scheme for solving them is provided. Two concrete algorithms are therefore designed that converge under suitable convexity and monotonicity … Read more