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Five levels of discrete wavelet transform are applied to decompose the ECG beat signal into six subband components. Higher order statistics proceeds to calculate valuable features from the three midband components. These features together with three RR interval-related features construct the primary feature set. A feature selection algorithm based on correlation coefficient and Fisher discriminality...
The automatic tracking of components allows a quick and consistent analysis of parameters related to biological experiments. The register of parameters is done by a system that analyzes a sequence of images and computes a number of descriptors characterizing the behavior of each target. Our objective is to create a framework for tracking in biological experiments, with multiple targets that may suffer...
The paper first deals with the design of Rayleigh fading channel simulators based on a Moving Average (MA) model. We present a new approach to estimate the model parameters based on the inner-outer factorization. The core of the approach consists of assimilating an infinite-order MA model to the outer spectral factor of the channel power spectral density (PSD). This outer factor, which leads to a...
We investigate distributed cooperative antenna (COOPA) systems with limited feedback. A feedback link is required to provide channel state information, and in many cases it is based on the codebook which consists of maximally spaced codes. The feedback overhead can be reduced by organizing the codebook structure in a smart way to exploit the temporal correlation of the channel. We have proposed the...
A kind of topology creation strategy for image analysis and classification is presented. The topology creation strategy automatically generates a relevance map from essential regions of natural images. It also derives a set of well-structured representations from low-level description to drive the final classification. The backbone of the topology creation strategy is a distribution mapping rule involving...
MIMO-OFDM receivers with horizontal encoding are considered in this paper. The successive interference cancellation (SIC) algorithm is compared to the K-best list sphere detector (LSD). The SIC and K-best LSD receivers are designed for a 2 × 2 antenna system with quadrature phase shift keying (QPSK), 16-quadrature amplitude modulation (QAM) and 64-QAM. The linear minimum mean squared error (LMMSE)...
Shift-invariant dictionaries are generated by taking all the possible shifts of a few short patterns. They are helpful to represent long signals where the same pattern can appear several times at different positions. We present an algorithm that learns shift invariant dictionaries from long training signals. This algorithm is an extension of K-SVD. It alternates a sparse decomposition step and a dictionary...
Two medieval manuscripts are recorded, investigated and analyzed by philologists in collaboration with computer scientists. Due to mold, air humidity and water the parchment is partially damaged and consequently hard to read. In order to enhance the readability of the text, the manuscript pages are imaged in different spectral bands ranging from 360 to 1000nm. A registration process is necessary for...
We present a denoising method that is well fitted to the processing of extremely irregular signals such as (multi)fractal ones. Such signals are often encountered in practice, e.g., in biomedical applications. The basic idea is to estimate the regularity of the original data from the observed noisy ones using the large scale information, and then to extrapolate this information to the small scales...
Most music genre classification techniques employ pattern recognition algorithms to classify feature vectors extracted from recordings into genres. An automatic music genre classification system using tensor representations is proposed, where each recording is represented by a feature matrix over time. Thus, a feature tensor is created by concatenating the feature matrices associated to the recordings...
We examine the robustness of several audio features applied exemplarily to musical instrument classification. For this purpose we study the robustness of 15 MPEG-7 Audio Low-Level Descriptors and 13 further spectral, temporal, and perceptual features against four types of signal modifications: low-pass filtering, coding artifacts, white noise, and reverberation. The robustness of the 120 feature coefficients...
Recent theoretical developments in the field of blind source separation (BSS) introduced the score function difference (SFD) and showed its close relationship with the differential of the mutual information. These results are of great interest for developing BSS methods since the mutual information can be seen as the canonical cost function for BSS. However these results were only proposed in the...
In this paper, a fast and an effective multi-view face tracking algorithm with head pose estimation is introduced. For modeling the face pose we employ a tree of boosted classifiers built using either Haar-like filters or Gauss filters. A first classifier extracts faces of any pose from the background. Then more specific classifiers discriminate between different poses. The tree of classifiers is...
Equation error adaptive algorithm (EQ-E) for an adaptive infinite impulse response (IIR) digital filter is one of the IIR adaptive algorithms that exhibit global convergence. In the presence of a disturbance signal, the coefficients of the equation error based adaptive digital filter (ADF) converge to solutions with bias. In this paper, we propose a kind of block adaptive algorithm for the EQ-E IIR...
EDGE preserving smoothing is an important step toward image segmentation. Currently, bilateral and mean shift filters are popular solutions to this problem. The multiscale mode filter proposed in this paper can be thought of as a generalization of both, working successively at a number of scales. As a result of the multiscale approach, the filter avoids being trapped into spurious local maxima, in...
Functional clustering is used to identify strongly interacting regions in the brain. In this study, functional clustering approach is applied to near infrared spectroscopy (NIRS) signals obtained during mental arithmetic task. Being a stress inducing task, mental arithmetic is known to cause a right lateral activation in the brain. We hypothesized that functional clusters would be more localized in...
Most applications of sparse representations are based on a combined ℓ2-ℓ1 criterion, where the least-squares-part ensures closeness to the observations and the ℓ1-part sparsity. This choice leads to quite efficient algorithms and has a clear connection to maximum likelihood approaches in case of additive Gaussian noise. We replace the least-squares-part by a ℓ1-part and investigate the recovery conditions...
In this paper, we introduce a distributed strategy for localization in a wireless sensor network composed of limited range sensors. The proposed distributed algorithm provides sensor position estimation from local similarity measurements. Incremental Kernel Principal Component Analysis techniques are used to build the nonlinear manifold linking anchor nodes. Non-anchor nodes positions are estimated...
This paper describes a scalable coder - G.711.1 - which has been standardized by ITU-T for wideband telephony and voice over IP applications. The main feature of this extension is to give wideband scalability to ITU-T G.711, the most widely deployed speech codec. G.711.1 is designed to achieve a very short delay and low complexity. ITU-T evaluation results show that the codec fulfils all the requirements...
We study the time-scale representation provided by the Morlet wavelet transform for characterizing NMR signals. From an analytical analysis and simulations, we conclude that the wavelet shows a satisfactory performance even when a baseline, an additive Gaussian noise or a solvent are present in the signals. It can also cope with non-Lorentzian lineshapes which commonly occur because of the inhomogeneous...
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