14 accepted papers
In this paper, we propose a novel strategy which utilizes an inherent algebraic property of simultaneously diagonalizable matrix tuples, i.e., commutativity, for both (i) reducing approximate CP decomposition of a higher-order tensor to Approximate Simultaneous Diagonalization (ASD) and (ii) solving…
In this paper, we present a novel formulation of Approximate Simultaneous Diagonalization (ASD) with a nonconvex feasibility problem to find a structured low rank matrix whose building blocks are the Kronecker sums of given multiple matrices. To tackle this feasibility problem, we propose an alterna…
In this paper, we propose a new linearly involved convexity-preserving model for signal recovery by extending the idea in the generalized minimax concave (GMC) penalty [Se-lesnick' 17]. The proposed model can use nonconvex penalties but maintain the overall convexity and is applicable to much more g…
Identification of piecewise continuous Hammerstein systems, which consist of the cascade of memoryless piecewise continuous systems followed by linear systems, is an important problem in engineering. In the identification process, major existing approaches approximate exact minimization of the non-c…
We propose a novel automatic shrinkage tuning technique for the adaptive proximal forward-backward splitting (APFBS) algorithm. The shrinkage tuning aims to choose an appropriate value of the shrinkage parameter and achieve minimal system mismatch as possible. The system mismatch is approximated bas…
In 2013, Nguyen and Yamada proposed Adaptive normalized quasi-Newton algorithm and its adaptive step size for accurate and stable extraction of the first generalized eigenvector. The adaptive step size is determined by an upper bound of the condition number of a time-varying matrix. However, the emp…
Decomposition of symmetric tensors has found numerous applications in blind sources separation, blind identification, clustering, and analysis of social interactions. In this paper, we consider fourth order symmetric tensors, and its symmetric tensor decomposition. By imposing unit-length constraint…
Exploiting the sparsity in learning algorithms is a key to achieve excellent performances of adaptive filters. This can be realized by the adaptive proximal forward-backward splitting with carefully chosen parameters. In this paper, we propose an automatic parameter tuning based on a minimization pr…
Finding a common point of multiple closed sets in a real Hilbert space has been an important task in a wide range of signal processing. In this paper, we study asymptotic properties of the parallel projection method (PPM) for closed sets satisfying a special feasibility condition, which holds in the…
This paper proposes fast iterative algorithms for solving convexly constrained spline smoothing through a characterization of solutions in a primal-dual space. In view of achievements for fast implementations of spline interpolation, the update of the proposed algorithm is designed as the compositio…
We propose an efficient image restoration framework based on stochastic optimization. Image restoration usually requires some iterative methods for solving optimization problems that characterize restored images, where the multiplication of the observation matrix Φ ϵ Rm × n and variables has to be c…
Nguyen and Yamada [NY'13] proposed an adaptive algorithm for fast and stable extraction of the first generalized Hermitian eigenvector and mentioned the extension to the first r generalized eigenvector extraction based on the nested orthogonal complement structure [NTY'12]. However, we recently foun…
Two-dimensional (2D) phase unwrapping is a reconstruction problem of a continuous phase, defined over 2D-domain, from its wrapped samples. In our previous work, we presented a two-step phase unwrapping algorithm which first constructs, as the real and imaginary parts of a complex function, a pair of…
In this paper, we propose a new modeling technique of signals having time-varying spectral patterns for supervised source separation. Typical examples of such signals are instrumental sounds having several segments such as “attack” and “sustain”. In the proposed technique, a given signal is modeled…