Global rational stabilization of a class of nonlinear time-delay systems

The present paper is mainly aimed at introducing a novel notion of stability of nonlinear time-delay systems called Rational Stability. According to the Lyapunov-type, various sufficient conditions for rational stability are reached. Under delay dependent conditions, we suggest a nonlinear time-delay observer to estimate the system states, a state feedback controller and the observer-based controller rational stability is provided. Moreover, global rational stability using output feedback is given. Finally, the study presents simulation findings to show the feasibility of the suggested strategy

Analyse locale de la forme 3D pour la reconnaissance d'expressions faciales

National audienceIn this paper we propose a novel approach for indentityindependent 3D facial expression recognition. Our approach is based on shape analysis of local patches extracted from 3D facial shape model. A Riemannian framework is applied to compute geodesic distances between correspondent patches belonging to different faces of the BU-3DFE database and conveying different expressions. Quantitative measures of similarity are obtained and then used as inputs to several classification methods. Using Multiboosting and Support Vector Machines (SVM) classifiers, we achieved average recognition rates respectively equal to 98.81% and 97.75%.Dans cet article, nous proposons une nouvelle approche pour la reconnaissance d'expressions faciales 3D invariante par rapport à l'identité. Cette approche est basée sur l'analyse de formes de " patches "locaux extraits à partir de modèles de visages 3D. Un cadre Riemannien est utilisé pour le calcul de distances géodésiques entre les patches correspondants appartenant a des visages différents sous différentes expressions. Des mesures quantitatives de similarité sont alors obtenues et sont utilisées comme des paramètres d'entrée pour des algorithmes de classification multiclasses. En utilisant des techniques de Multiboosting et de Machines à Vecteurs de Support (SVM), les taux de reconnaissance des six expressions de base obtenus sur la base BU-3DFE sont respectivement 98.81% et 97.75%

Bayesian Modeling in Genetics and Genomicsvvv

This chapter provides a critical review of statistical methods applied in animal and plant breeding programs, especially Bayesian methods. Classical and Bayesian procedures are presented in pedigree-based and marker-based models. The flexibility of the Bayesian approaches and their high accuracy of prediction of the breeding values are illustrated. We show a tendency of the superiority of Bayesian methods over best linear unbiased prediction (BLUP) in accuracy of selection, but some difficulties on elicitation of some complex prior distributions are investigated. Genetic models including marker and pedigree information are more accurate than statistical models based on markers or pedigree alone

Fitting lactation curves of dairy cattle in different types of herds in Tunisia

peer reviewedThe incomplete gamma function was used to fit lactation curves of Holstein-Friesian cows in four types of herds in Tunisia. A total of 8640 records were used in the analysis. These included 1269, 637, 239, and 498 first lactation and 2986, 1441, 650, and 920 second and later lactation records in four herd groups namely investors, state, cooperative, and farmers' herds, respectively. The effects of environmental variables, production sector, herd, parity, first test-day date, calving year, and calving season on the main lactation curve traits were analysed. The factors associated with milk yield at the beginning of lactation and the decreasing phase of the curve, persistency, and peak yield varied significantly (P<0.01) with all variables. The ascending phase of the lactation curve was not affected by parity and calving year, while days in milk until peak depended only on the rank of lactation. The state herds had the lowest peak and total yields. The summer season was unfavourable for milk production. In contrast to first lactation cows, third lactation cows had the highest peak and total yields. Milk yield was highly correlated with peak yield (r = 0.79) and was not related to persistency measure. (C) 2003 Elsevier B.V. All rights reserved

Quelles caractéristiques géométriques faciales 3D donnent votre identité ?

Session "Articles"National audienceLa reconnaissance de visages 3D basée sur les courbes faciales 3D de différentes natures (courbes de niveaux, courbes iso-géodésiques, courbes radiales, profils, polarisation géodésique, etc), est une problématique de reconnaissance des formes largement abordée dans la littérature. Cette représentation par des courbes permet notamment d'analyser localement la forme de la surface faciale contrairement aux approches basées sur les surfaces entières. Elle a l'avantage de faire face aux variations de la pose (le visage test peut correspondre seulement à une partie du visage enrôlé) ou dans le cas des données manquantes (visage altéré par les occultations). Deux questions qui n'ont pas été abordés dans la littérature sont: Est ce que l'utilisation de toutes les courbes du visage aboutissent aux meilleures performances? Y a-t-il des courbes faciales plus pertinentes que d'autres? Nous essayons de répondre à ces questions dans cet article. Premièrement, nous représentons les surfaces faciales comme des collections de courbes de niveaux et radiales. Ensuite, en utilisant la géométrie Riemannienne nous analysons leurs formes. Enfin nous utilisons l'algorithme AdaBoost pour sélectionner les courbes (caractéristiques géométriques) les plus discriminantes. Les expérimentations, réalisées sur la base FRGCv2 avec le protocole standard, donne un taux de reconnaissance de 98.02% qui est un résultat compétitif vis-à-vis de l'état de l'ar