Nonnegative matrix factorization (NMF) has proven to be a useful tool for the analysis of nonnegative multivariate data. However, it is known not to lead to unique results when applied to blind source separation (BSS) problems. In this paper we present an extension of NMF capable of solving the BSS problem when the underlying sources are sufficiently sparse. In contrast to most well-established...

We propose a new blind source separation algorithm based on mixtures of alpha-stable distributions. Complex symmetric alpha-stable distributions have been recently showed to better model audio signals in the time-frequency domain than classical Gaussian distributions thanks to their larger dynamic range. However, inference of these models is notoriously hard to perform because their probability...

Background: Emotion regulation and separation anxiety are some of the problems faced by elementary-school students. This study aimed to investigate the effectiveness of cognitive-behavioral play therapy (CBPT) on emotion regulation and separation anxiety of elementary-school children in Isfahan. Methods: This quasi-experimental study was conducted using a pretest-posttest design with a contro...

   Graphene oxide nanosheet (GONS) can be a suitable membrane for gas separation with high permeability and selectivity. Separation of N2/CO2 using functionalized GONS was investigated by molecular dynamics simulations. The simulated systems were comprised of two types of GONS with a pore in their center, N2 and CO2 molecules. The selectivity and ...

The blind source separation (BSS) problem is often solved by maximizing objective functions reflecting the statistical independence between outputs. Since global maximization may be difficult without exhaustive search, criteria for which all the local maxima correspond to an acceptable solution of the BSS problem are of interest. It is known that some BSS criteria used in a deflation procedure ...

This paper deals with blind separation of convolutive mixtures of continuous phase modulated (CPM) sources. The main difficulty lies in the fact that CPM sources are non-linear (and hence non i.i.d.) sources. The problem is addressed through the general formulation of blind source separation (BSS). The separation method consists in iterative constrained optimizations of criteria depending on th...

Human reaction times during sensory-motor tasks vary considerably. To begin to understand how this variability arises, we examined neuronal populational response time variability at early versus late visual processing stages. The conventional view is that precise temporal information is gradually lost as information is passed through a layered network of mean-rate "units." We tested in humans w...

In this paper, a non-parametric “gradient” of the mutual information is first introduced. It is used for showing that mutual information has no local minima. Using the introduced “gradient”, two general gradient based approaches for minimizing mutual information in a parametric model are then presented. These approaches are quite general, and principally they can be used in any mutual informati...

In this paper a method to simultaneously achieving the two main objective of smoothing the control while maintaining ideally infinite frequency regimes is particularized to the simplex sliding mode method. The present paper proposes a simplex sliding mode control logic based on the time derivative of the control vector. This practice, beside the standard chattering reduction effect, has the imp...

Recent studies show that facial information contained in visual speech can be helpful for the performance enhancement of audio-only blind source separation (BSS) algorithms. Such information is exploited through the statistical characterization of the coherence between the audio and visual speech using, e.g., a Gaussian mixture model (GMM). In this paper, we present three contributions. With th...