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arXiv · 2105.02994

A Convexly Constrained LiGME Model and Its Proximal Splitting Algorithm

Wataru Yata·Masao Yamagishi·Isao Yamada
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Abstract

For the sparsity-rank-aware least squares estimations, the LiGME (Linearly involved Generalized Moreau Enhanced) model was established recently in [Abe, Yamagishi, Yamada, 2020] to use certain nonconvex enhancements of linearly involved convex regularizers without losing their overall convexities. In this paper, for further advancement of the LiGME model by incorporating multiple a priori knowledge as hard convex constraints, we newly propose a convexly constrained LiGME (cLiGME) model. The cLiGME model can utilize multiple convex constraints while preserving benefits achieved by the LiGME model. We also present a proximal splitting type algorithm for the proposed cLiGME model. Numerical experiments demonstrate the efficacy of the proposed model and the proposed optimization algorithm in a scenario of signal processing application.

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Wataru Yata, Masao Yamagishi, Isao Yamada. 2021-05-06. A Convexly Constrained LiGME Model and Its Proximal Splitting Algorithm. https://arxiv.org/abs/2105.02994

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