This paper presents an application of a hierarchical social (HS) metaheuristic to region-based segmentation. The original image is modelled as a simplified image graph, which is successively partitioned into two regions, corresponding to the most significant components of the actual image, until a termination condition is met. The graph-partitioning task is solved as a variant of the min-cut pr...

This paper presents a new variable step-size normalized subband adaptive filter (VSS-NSAF) algorithm. In the proposed VSS-NSAF, the step-size changes in order to have largest decrease in the mean square deviation (MSD) for sequential iterations. To reduce the computational complexity of VSS-NSAF, the variable step-size selective partial update normalized subband adaptive filter (VSS-SPU-NSAF) i...

In this work we propose a randomized algorithm to estimate the street-level commuting route using call detail records (CDRs). Our algorithm works in three steps. First, for each individual, we create perturbations of estimated home and work locations within the cell tower coverage. Second, we identify a route between each pair of both locations through a web mapping service. Finally, we choose ...

Geometric attacks are among the most challenging problems in present day watermarking. Such attacks are very simple to implement yet they can defeat most of the existing watermarking algorithms without causing serious perceptual image distortion. In this paper we propose a new public watermarking algorithm, which is robust to such attacks. This algorithm uses a normalized with respect to affine...

A novel feedback-based spike detection algorithm for noisy spike trains is presented in this paper. It uses the information extracted from the results of spike classification for the enhancement of spike detection. The algorithm performs template matching for spike detection by a normalized correlator. The detected spikes are then sorted by the OSortalgorithm. The mean of spikes of each cluster...

Brain tumor segmentation from Magnetic Resonance Images (MRIs) is an important task to measure tumor responses to treatments. However, automatic segmentation is very challenging. This paper presents an automatic brain tumor segmentation method based on a Normalized Gaussian Bayesian classification and a new 3D Fluid Vector Flow (FVF) algorithm. In our method, a Normalized Gaussian Mixture Model...

The Laplacian eigenvalues of a network play an important role in the analysis of many structural and dynamical network problems. In this paper, we study the relationship between the eigenvalue spectrum of the normalized Laplacian matrix and the structure of ‘local’ subgraphs of the network. We call a subgraph local when it is induced by the set of nodes obtained from a breath-first search (BFS)...

In order to accelerate the motion estimation process, the normalized partial distortion search algorithm calculates the partial distortion by constantly selecting specific pixels from every sub-macroblock to early reject the incorrect motion vector. However, these selected pixels are supposed that the pixels’ values of sub-macroblock are uniform distribution. This paper proposes a partial disto...

The proportionate normalized least-mean-square (PNLMS) algorithms were developed in the context of network echo cancellation. They outperform the normalized leastmean-square (NLMS) algorithm only when the echo path is sparse. Unfortunately, realworld network echo path may not be that sparse sometimes, while the acoustic echo paths are usually less sparse. The improved PNLMS (IPNLMS) algorithm i...