New adaptive proximal gradient algorithms for solving multiobjective composite optimization problems

In this paper, we propose new adaptive proximal gradient algorithms to solve multiobjective optimization problems, where each objective function is the sum of a differentiable function and a proper, closed, convex function. Utilizing the local behavior of the differentiable terms we propose new adaptive ways to select stepsizes used in proximal gradient scheme. In particular, … Read more

Solution of Binary-Constrained Quadratic-Defined Optimization Problems by a Progressive Integer Programming Method

Extending a classic result of Giannessi and Tomasin [\textit{Lecture Notes in Comput. Sci. 3}, Springer, 1973, pp. 437–449], this paper shows that a binary-constrained quadratic-defined optimization problem can be formulated as a binary-constrained linear program with linear complementarity constraints (Bi-LPCC). The term “quadratic-defined problems” encompasses many problems that are defined by quadratic functions in the … Read more

Two-stage approach for the predispatch problem with uncertain demand using splitting variables in interior-point methods

The stochastic predispatch optimal power flow problem aims to minimize generation costs and transmission losses subject to network constraints under demand uncertainty. We formulate it as a two-stage stochastic quadratic optimization problem with fixed recourse, in which hydroelectric generation constitutes the here-and-now decision, while thermal generation and transmission flows are recourse decisions. Using a splitting-variable … Read more

The best approximation tuple: an extension of the Cheney-Goldstein algorithm and results to the multiple sets case

In this paper we extend the algorithm and several results published in the celebrated 1959 paper of Cheney and Goldstein about the best approximation pair (BAP) problem in two separate directions. One is the consideration of more than two sets. The other is the ability to handle each set as an intersections of a finite … Read more

Integer quadratic programming in fixed dimension is polynomial-time solvable

We give a deterministic polynomial-time algorithm for integer quadratic programming in every fixed dimension: it minimizes an arbitrary rational quadratic exactly over the integer points of a rational polyhedron, or certifies infeasibility or integer unboundedness. The core is a sign test that decides whether \(d^{\mathsf{T}}Qd\ge 0\) for every integer point \(d\) of a bounded symmetric … Read more

Unshackling Column Generation for Linearized Unconstrained Binary Quadratic Programs

When linearizing binary quadratic programs, the most usual way is to replace bilinear products with additional variables constrained to take on consistent values in any feasible solution. In this setting, column generation is a principally desirable solution technique, for instance because the number of such additional linearization variables may be large while many of them … Read more

A Proximal Approach for Nonsmooth Composite-Constrained Optimization

We propose a proximal-type algorithm for nonsmooth and nonconvex optimization problems with composite constraints. The constraint is defined by the composition of a locally upper-\(C^2\) outer function with a locally Lipschitz continuous inner mapping. The method is based on an improvement function that balances objective decrease and constraint satisfaction, and on a surrogate model obtained … Read more

Non-monotone direct-search methods for deterministic and stochastic derivative-free optimization

In derivative-free optimization (DFO), one minimizes functions for which the gradient is unavailable or expensive to compute. In many applications, objective function values and gradients are noisy due to simulations or system randomness. A class of standard direct-search methods for DFO accept a trial point when it decreases the objective function by an amount proportional … Read more

Stable and Unstable Singularities in Navier-Stokes ?

This document provides an extended and rigorous framework dedicated to the geometric analysis of the 3D incompressible Navier-Stokes equations \cite{ESS2003}. We comprehensively develop geometric proofs related to decay estimates, blow-up profiles, and the foundational partial regularity theory of Caffarelli, Kohn, and Nirenberg (CKN). We examine in detail the Hausdorff dimension of potential singular sets, local … Read more

Rooting Out Self-Intersection: An Algebraic Shape-Optimization Barrier

Self-intersection is a fundamental feasibility constraint in shape optimization: a self-crossing boundary leaves its interior, normal field, and finite-element mesh ill-defined, yet most existing barriers rely on heuristic geometric-proximity measures rather than certifying self-intersection directly. We propose a self-intersection barrier grounded in algebraic detection. We derived two bivariate polynomials from a curve’s Fourier coefficients whose … Read more