460 citations · 1.2k across the 40 of their papers we have counts for
24 papers · 1 filter
An accelerated randomized Bregman-Kaczmarz method for strongly convex linearly constraint optimization
Lionel Tondji, Dirk A. Lorenz, Ion Necoara
In this paper, we propose a randomized accelerated method for the minimization of a strongly convex function under linear constraints. The method is of Kaczmarz-type, i.e. it only…
A Bregman-Kaczmarz method for nonlinear systems of equations
Robert Gower, Dirk A. Lorenz, Maximilian Winkler
We propose a new randomized method for solving systems of nonlinear equations, which can find sparse solutions or solutions under certain simple constraints. The scheme only takes…
The Degenerate Variable Metric Proximal Point Algorithm and Adaptive Stepsizes for Primal-Dual Douglas-Rachford
Dirk A. Lorenz, Jannis Marquardt, Emanuele Naldi
In this paper the degenerate preconditioned proximal point algorithm will be combined with the idea of varying preconditioners leading to the degenerate variable metric proximal po…
-Regularization of the Beckmann Problem
Dirk Lorenz, Hinrich Mahler, Christian Meyer
We investigate the problem of optimal transport in the so-called Beckmann form, i.e. given two Radon measures on a compact set, we seek an optimal flow field which is a vector valu…
Chambolle-Pock's Primal-Dual Method with Mismatched Adjoint
Dirk A. Lorenz, Felix Schneppe
The primal-dual method of Chambolle and Pock is a widely used algorithm to solve various optimization problems written as convex-concave saddle point problems. Each update step inv…
Nonconvex flexible sparsity regularization: theory and monotone numerical schemes
Daria Ghilli, Dirk A. Lorenz, Elena Resmerita
Flexible sparsity regularization means stably approximating sparse solutions of operator equations by using coefficient-dependent penalizations. We propose and analyse a general no…