242 citations · 1.1k across the 27 of their papers we have counts for
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Analysis of the Optimization Landscapes for Overcomplete Representation Learning
Qing Qu, Yuexiang Zhai, Xiao Li +2
We study nonconvex optimization landscapes for learning overcomplete representations, including learning (i) sparsely used overcomplete dictionaries and (ii) convolutional dictiona…
Weakly Convex Optimization over Stiefel Manifold Using Riemannian Subgradient-Type Methods
Xiao Li, Shixiang Chen, Zengde Deng +3
We consider a class of nonsmooth optimization problems over the Stiefel manifold, in which the objective function is weakly convex in the ambient Euclidean space. Such problems are…
Short-and-Sparse Deconvolution -- A Geometric Approach
Yenson Lau, Qing Qu, Han-Wen Kuo +3
Short-and-sparse deconvolution (SaSD) is the problem of extracting localized, recurring motifs in signals with spatial or temporal structure. Variants of this problem arise in appl…
A Nonconvex Approach for Exact and Efficient Multichannel Sparse Blind Deconvolution
Qing Qu, Xiao Li, Zhihui Zhu
We study the multi-channel sparse blind deconvolution (MCS-BD) problem, whose task is to simultaneously recover a kernel and multiple sparse inputs $\{\mathbf x_i\}_{i=…