Signal

We propose a novel Bayesian formulation for the reconstruction from compressed measurements. We demonstrate that high-sparsity enforcing priors based on lp-norms, with 0< p≤ 1, can be used within a Bayesian framework by majorization-minimization methods. By employing a fully Bayesian analysis of the compressed sensing system and a variational Bayesian analysis for inference, the proposed framework provides model parameter estimates along with the unknown signal, as well as the uncertainties of ...

Ce travail concerne le developpement d'un systeme de conversion de voix oesophagienne dans le but est de rendre plus intelligible celle-ci. La conversion de voix est une technique de transformation d'un signal de parole d'un locuteur source, de maniere a ce qu'il semble, a l'ecoute, etre prononce par un locuteur cible. Etant donnee la specificite de la voix oesophagienne, nous proposons dans cette etude d'appliquer une nouvelle technique de conversion vocale en tenant compte de la particularite de l'appareil vocal des patients qui ont subi une ablation de larynx. En effet, l'ablation des cordes vocales perturbe profondement le signal glottique et par consequent la voix oesophagienne acquise par le patient laryngectomise est difficile a comprendre, rauque et faible en intensite. Dans la litterature, plusieurs techniques de conversion des voix ont ete proposees, parmi lesquelles, la technique du codage lineaire predictif pour la conversion vocale [1] et...

TNF-related weak inducer of apoptosis (TWEAK) is a new member of the TNF superfamily. It signals through TNFRSF12A, commonly known as Fn14. The TWEAK-Fn14 interaction regulates cellular activities including proliferation, migration, differentiation, apoptosis, angiogenesis, tissue remodeling and inflammation. Although TWEAK has been reported to be associated with autoimmune diseases, cancers, stroke, and kidney-related disorders, the downstream molecular events of TWEAK-Fn14 signaling are yet not available in any signaling pathway repository. In this paper, we manually compiled from the literature, in particular those reported in human systems, the downstream reactions stimulated by TWEAK-Fn14 interactions. Our manual amassment of the TWEAK-Fn14 pathway has resulted in cataloging of 46 proteins involved in various biochemical reactions and TWEAK-Fn14 induced expression of 28 genes. We have enabled the availability of data in various standard exchange formats from NetPath, a reposito...

Two functionally distinct sets of meristematic cells exist within root tips of pea (Pisum sativum): the root apical meristem, which gives rise to the body of the root; and the root cap meristem, which gives rise to cells that differentiate progressively through the cap and separate ultimately from its periphery as border cells. When a specific number of border cells has accumulated on the root cap periphery, mitosis within the root cap meristem, but not the apical meristem, is suppressed. When border cells are removed by immersion of the root tip in water, a transient induction of mitosis in the root cap meristem can be detected starting within 5 min. A corresponding switch in gene expression throughout the root cap occurs in parallel with the increase in mitosis, and new border cells begin to separate from the root cap periphery within 1 h. The induction of renewed border cell production is inhibited by incubating root tips in extracellular material released from border cells. The ...

In this paper the problem of face recognition under variable illumination conditions is considered. Most of the works in the literature exhibit good performance under strictly controlled acquisition conditions, but the performance drastically drop when changes in pose and illumination occur, so that recently number of approaches have been proposed to deal with such variability. The aim of this work is to introduce an efficient local appearance feature extraction method based steerable pyramid (SP) for face recognition. Local information is extracted from SP sub-bands using LBP(Local binary Pattern). The underlying statistics allow us to reduce the required amount of data to be stored. The experiments carried out on different face databases confirm the effectiveness of the proposed approach.

Under commonwealth of the outlier extinguish inspection, exclusively on the impulsive outlier, the outlier extinguish algorithm is a substantial step, which is early performed prior to further computer vision steps thereupon the iterative mean filter (IMF) is inaugurated for fix value impulsive noise (FVIN) and grown into one of the superior achievement outliers extinguish algorithms. This academic article focuses to investigate the correlative achievement of the outlier extinguish algorithm established on IMF, is inaugurated from mean filter (MF) for carrying out the poor achievement of the aforesaid outlier extinguish algorithms (standard median filter (SMF), MF, and adaptive median filter (AMF)), for FVIN at omnipresent scattering of outlier consistency (5-90%). The analytical experiment comprehensively exploits on bountiful figures (F16, Girl, Lena, and Pepper) that are inspected in order to analyze the correlative achievement of an outlier extinguish algorithm established on IMF. In contrast with the aforesaid outlier extinguish algorithms (SMF, MF, and AMF), the outlier extinguish algorithm established on IMF has superior achievement from the experimental results.

Au CFA de 2014 nous presentions le caveau phonocamptique de la Cathedrale de Noyon qui comporte, dans un espace souterrain reduit (15 m²), un nombre important de pots acoustiques (64). L’etude des livres liturgiques et de la documentation de la cathedrale (XVe-XVIIe siecles) ne permet pas a ce jour d’identifier le role et l’usage de ce caveau. Pourtant, les etudes archeologiques et acoustiques que nous avions presentees en 2014 montraient le soin qu’avaient pris les bâtisseurs pour elaborer cet espace : deux modeles de pots de hauteurs differentes, correspondant a deux frequences moyennes proches d’une quarte musicale, une repartition choisie dans l’espace et un travail de maconnerie particulierement soigne. Afin d’en comprendre l’usage, la question est de savoir si les chantres descendaient dans le caveau et si les pots avaient un effet sur leur performance. En effet, la taille reduite de la salle permet d’envisager un effet reel et mesurable des pots, a la difference des dispositi...

SAR images provide detailed information about the target surface, though it is obscured by the well-known speckle effect. One alternative of speckle reduction is by ffitering the image, but this demands some assumptions about the speckle behaviour. However, it is important to take into account that noise reduction filters tend to blur the edges and sharp features of the images, since they always introduce some kind of low pass effect. Several filters have been developed for the speckle reduction, and most of them are of the form of a window that slides over de image. But there is no automatic process to determine the window size, a relevant parameter that depends, among other things, on the features of the studied arca. Given a filter, it can be applied to the S AR image for different window sizes; then it is possible to estimate the so-called speclde index as a measure that provides the best speclde reduction in accordance to the degree of heterogeneity of the region under study. I...

In this paper we present an adaptive method for image compression that is based on complexity level of the image. The basic compressor/de-compressor structure of this method is a multilayer perceptron artificial neural network. In adaptive approach different Back-Propagation artificial neural networks are used as compressor and de-compressor and this is done by dividing the image into blocks, computing the complexity of each block and then selecting one network for each block according to its complexity value. Three complexity measure methods, called Entropy, Activity and Pattern-based are used to determine the level of complexity in image blocks and their ability in complexity estimation are evaluated and compared. In training and evaluation, each image block is assigned to a network based on its complexity value. Best-SNR is another alternative in selecting compressor network for image blocks in evolution phase which chooses one of the trained networks such that results best SNR i...

Modern serialization formats for digital video data are designed in a way that they allow for the combination of high compression rates, high quality as well as performant enand decoding. As the capability for real-time decoding often is a requirement, concrete decoders are usually implemented in a way that they best fit a specific architecture and, thus, are not portable. In scenarios, where it is essential that the capability to decode existent video data can be retained, even if the underlying architecture is changed, portability is more important than performance. For such scenarios, we propose decoder specifications that serve as templates for concrete decoder implementations on different architectures. As a high level of abstraction guarantees system-independence, we use (meta)models and model transformations for that purpose. Consequently, every decoder specification is (partially) executable, which simplifies the development process. In this paper, we describe our concepts f...

Synchronous programming models capture concurrency in computation quite naturally, especially in its dataflow multi-clock (polychronous) flavor. With the rising importance of multi-core processors in safety-critical embedded systems or cyber-physical systems (CPS), there is a growing need for model-driven generation of multi-threaded code and thus mapping on multi-core (i.e. multi-core code). This paper would like to propose a build method of time-predictable system on multi-core, based on synchronous-model development. At the modeling level, the synchronous abstraction allows deterministic time semantics. Thus synchronous programming is a good choice for time-predictable system design. At the compiler level, the verified compiler from the synchronous language SIGNAL to our intermediate representation (S-CGA, a variant of guarded actions) and thus to multi-threaded code, preserves the time predictability. At the platform level, we propose a time-predictable multi-core architecture m...

Le mini-satellite Corot lance en 2006 utilisera la methode des transits : Une exoplanete signe son passage devant l'etoile par une breve baisse de flux inferieure au millieme. La stabilite et continuite de mesure seront assurees sur 150 jours pour 60. 000 etoiles afin d'augmenter le nombre de configurations favorables. La photometrie d'ouverture integre chaque flux dans un masque de lecture adapte aux multiples bruits, limite a 250 formes differentes pour 12. 000 cibles. J'ai etudie des methodes autorisant cette reduction sans perte notable de signal a bruit. Le tri efficace de masques aleatoires s'avere la plus satisfaisante. Pour la detection, j'ai developpe une methode qui rehausse le contraste des transits en eliminant les composantes des effets collectifs et de certains artefacts. Apres detection temporelle les systematiques sont identifiees, meme celles d'origine et de poids inconnus. On fait emerger de nouvelles detections en jaugeant la dispersion...

Steganography has proven to be one of the practical ways of securing data. It is a new kind of secret communication used mainly to hide secret data inside other innocent digital mediums. Most of existing steganographic techniques use digital multimedia files as cover mediums to hide secret data. Audio files and signals make appropriate mediums for steganography due to the high data transmission rate and the high level of redundancy. Hiding data in real time communication audio signals is not a simple mission. ...

Impedance cardiography is a noninvasive technique for monitoring stroke volume, based on sensing variation in the thoracic impedance, z(t), due to blood flow. In this technique, first derivative of impedance, dz/dt, is used to calculate two parameters: ventricular ejection time and (-dz/dt)<inf>max.</inf>Respiration and motion artifacts cause base line drift in the sensed impedance waveform, mainly during exercise, and this drift results in errors in the estimation of the two parameters. Ensemble averaging of z(t) signal suppresses motion artifacts but it introduces distortion in the signal. In this study, simultaneously acquired respiratory signal is used for cancellation of corrupting respiratory artifact from the recorded z(t) signal, using adaptive noise cancellation technique.

A review is presented of ongoing research on the oligosaccharide signalsinvolved in cell-cell recognition in the Chondrus crispus-Acrochaete operculata host-pathogen association. In this pathosystem,the host gametophytes are resistant to the pathogen, whereas thesporophytic generation is susceptible to infection. The virulence of thegreen algal pathogen is mediated by the recognition of carrageenanoligosaccharides released from its red algal host: kappa-carrageenanoligosaccharides inhibit A.