Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
Peer Reviewed
See detailPrédiction de mobilité par le mobile ou par le point d'accès: comparaison sur base de traces réelles
François, Jean-Marc; Leduc, Guy ULg

in CFIP'2006 (2006, November)

Le problème de la prédiction de mobilité se définit comme le fait de deviner quel sera le prochain point d'accès rencontré par un terminal mobile lors de son déplacement dans un réseau sans fil. Les ... [more ▼]

Le problème de la prédiction de mobilité se définit comme le fait de deviner quel sera le prochain point d'accès rencontré par un terminal mobile lors de son déplacement dans un réseau sans fil. Les prédictions faites permettent d'améliorer la qualité de service fournie par le réseau en lui permettant de prendre des mesures pro-actives (telles des réservations de ressources). Les agents de prédiction se classent principalement en deux catégories: les agents liés à un mobile particulier (responsables d'anticiper les déplacements de celui-ci) et ceux liés à un point d'accès (prédisant le prochain point d'attache de tous les terminaux y étant connectés). Cet article vise à comparer les deux méthodes à l'aide de traces réelles tirées d'un réseau WiFi de grande taille. Il montre que certains postulats souvent admis (comme le fait que les habitudes de mouvement du week-end sont différentes de celles du reste de la semaine) doivent être revus. [less ▲]

Detailed reference viewed: 32 (6 ULg)
Full Text
See detailPrédiction de structures de macromolécules par apprentissage automatique
Marcos Alvarez, Alejandro ULg

Master's dissertation (2011)

Proteins are an essential constituent of cellular life whose biggest part of their function is determined by their tridimensional shape. Nowadays, however, no method is able to predict efficiently ... [more ▼]

Proteins are an essential constituent of cellular life whose biggest part of their function is determined by their tridimensional shape. Nowadays, however, no method is able to predict efficiently tridimensional protein structures based only on their amino acids sequence. We propose here an "ab initio" approach based on the concept of learning for search. Protein structure prediction is modeled in the form of an optimization problem solved by an optimization algorithm that follows an iterative framework in which a structure modification operator is selected and then applied to the current structure. The quality of the new structure is then assessed by an oracle that will determine whether or not the structure is accepted. The repetition of this framework will eventually lead to the sought structure. The critical point of this rationale lies in the choice of the modification operator, which has to be done very accurately in order to avoid the classical pitfalls of optimization problems. The operator selection step will then be subjected to machine learning thus legitimizing the term "learning for search" of the proposed method. The goal of this thesis is to show that machine learning can improve the results obtained via a simple optimization procedure. Our experiments show that this goal is fulfilled. We however know that many choices that we did should be questioned regarding both the optimization and the machine learning procedures. Finally, we can notice that the application domain of this work extends beyond the protein structure prediction problem. There exist indeed many optimization problems in the scientific literature for which no exact neither approximation algorithm exists and that are thus still very badly solved. Such problems could greatly benefit from a "learning for search" approach such as the one described in this work. [less ▲]

Detailed reference viewed: 198 (35 ULg)
Full Text
See detailPrédiction des performances sportives et détection précoce des myopathies par respirométrie à haute résolution
Votion, Dominique ULg; Serteyn, Didier ULg

in cheval athlète, stress oxydant & inflammation (2013, June 07)

Detailed reference viewed: 46 (19 ULg)
Full Text
Peer Reviewed
See detailPrédiction des zones propices au ravinement par un modèle de régression logistique intégrant des données de télédétection. Cas du sous-bassin versant de l’oued Alayem - Beni Slimane, Algérie
Daoudi, Mohamed; Ozer, André ULg; Gérard, Paul ULg et al

in Randriamanga, Simone; Rakotoniaina, Solofoarisoa; Auda, Yves (Eds.) et al Les XIèmes Journées Scientifiques du Réseau Télédétection de l'AUF (2008, November 03)

Le sous-bassin versant de l'oued Alayem - Beni Slimane, d’une superficie de 118 km², constitue une zone d'étude d'intérêt particulier en raison des caractéristiques physicoclimatiques représentatives de ... [more ▼]

Le sous-bassin versant de l'oued Alayem - Beni Slimane, d’une superficie de 118 km², constitue une zone d'étude d'intérêt particulier en raison des caractéristiques physicoclimatiques représentatives de la zone tellienne méditerranéenne. Le processus de ravinement y est très répandu et constitue un problème majeur. Les facteurs physiques et anthropiques contribuent à une accélération du phénomène. Le présent travail propose une méthode multivariée, basée sur des données multisources, afin de déterminer les variables indépendantes significatives qui favorisent l’existence de l’érosion ravinante et calculer la probabilité des zones de susceptibilité au processus de ravinement. Des variables explicatives toutes liés aux caractéristiques physico-climatiques sont retenues pour le modèle : il s’agit de la lithologie, la pente, l’orientation des versants, l’altitude (MNT), la morphopédologie, la couverture du sol (PVI) et l’agressivité des précipitations (Indice R). Elles permettent de généraliser le modèle prédictif pour des régions semblables du nord de l’Algérie ou du Maghreb. [less ▲]

Detailed reference viewed: 21 (0 ULg)
Full Text
Peer Reviewed
See detailPrédiction du gras intermusculaire du porc Piétrain par l'ultrasonographie en temps réel
Youssao, A. K. I.; Verleyen, Vincent ULg; Michaux, Charles ULg et al

in Viandes & Produits Carnés - Hors série "10èmes journée Sciences du Muscle et Technologies des Viandes" (2004)

Detailed reference viewed: 69 (3 ULg)
See detailLa prédiction et l'évaluation de l'efficacité des professeurs
De Landsheere, Gilbert ULg

in Revue Belge de Psychologie et de Pedagogie (1963), 104

The accurate evaluation of the efficaciousness of the teachers is impossible because many variables interfere. An objective description of the behavior of the teacher is preferable.

Detailed reference viewed: 6 (0 ULg)
See detailLa prédiction et l'évaluation de l'efficacité des professeurs
de Landsheere, Gilbert ULg

in Revue Belge de Psychologie et de Pédagogie (1963), 25(104), 93-111

Detailed reference viewed: 10 (0 ULg)
Full Text
Peer Reviewed
See detailPrédiction numérique des défauts de forme engendrés par l'usinage
Debongnie, Jean-François ULg; Masset, Luc ULg

in Actes du 7ème Congrès de Mécanique. Volume I. Mécanique des Solides (2005, April)

Presentation of a prediction method of form errors arising during machining which has been developed in the manufacturing laboratory of the University of Liège. It combines empirical force models and a ... [more ▼]

Presentation of a prediction method of form errors arising during machining which has been developed in the manufacturing laboratory of the University of Liège. It combines empirical force models and a finite element model of the machined part. A particularly efficient solution scheme has been developed, leading to a valuable tool for the industry. [less ▲]

Detailed reference viewed: 73 (9 ULg)
Full Text
Peer Reviewed
See detailPrediction of acid mine generating potential: Validation using mineralogy
Bouzahzah, Hassan; Benzaazoua, Mostafa; Plante, Benoît et al

in Proceedings 24th International Applied Geochemistry Symposium (2009)

Detailed reference viewed: 49 (8 ULg)
Peer Reviewed
See detailPrediction of Body Weight of Primiparous Dairy Cows Throughout Lactation
Vanrobays, Marie-Laure ULg; Vandenplas, Jérémie ULg; Hammami, Hedi ULg et al

in Proceedings of the 10th World Congress on Genetics Applied to Livestock Production (2014, August)

Body weight (BW) can be computed using linear conformation traits (CBW). However, these traits are recorded mostly once during a lactation. Therefore, predicted BW (PBW) is needed throughout the lactation ... [more ▼]

Body weight (BW) can be computed using linear conformation traits (CBW). However, these traits are recorded mostly once during a lactation. Therefore, predicted BW (PBW) is needed throughout the lactation (e.g., allowing feed intake prediction in milk recording systems). A two-step procedure was developed to obtain PBW using a random regression test-day model using CBW as observations. Added second step consisted in changing prior distribution for additive genetic random effects using results from first step to predict again PBW. This method was applied on 24,919 primiparous Holstein cows having 25,061 CBW to obtain PBW for 232,436 test-days. Results showed that applying both steps provided more accurate estimates than using only the first step. Furthermore, this procedure predicting PBW throughout lactation is also extremely flexible because actual BW can also be used together with CBW, the prediction model being able to accommodate different levels of accuracies. [less ▲]

Detailed reference viewed: 28 (12 ULg)
Full Text
Peer Reviewed
See detailPrediction of Bone Loss Rate in Healthy Postmenopausal Women
Reginster, Jean-Yves ULg; Deroisy, Rita ULg; Collette, Julien ULg et al

in Calcified Tissue International (1997), 60(3), 261-4

Prevention of fractures is the only way to drastically reduce osteoporosis-related health expenditures. In order to optimize the cost/benefit ratio of a strategy of prevention, it is essential to identify ... [more ▼]

Prevention of fractures is the only way to drastically reduce osteoporosis-related health expenditures. In order to optimize the cost/benefit ratio of a strategy of prevention, it is essential to identify, as early as possible, women who will develop fractures later in their life. Therefore, and since postmenopausal bone loss is an asymptomatic process, screening procedures should detect, at the time of the menopause, women whose postmenopausal bone loss is higher than the mean, and will, a couple of years later, exhibit a low mineral content and a subsequent high risk for fractures. For 3 years we have followed a cohort of 92 healthy women who had undergone menopause less than 36 months previously. By a multivariate discriminant analysis based on the differences in lumbar bone density, assessed by dual photon absorptiometry, and in a few routine biochemical parameters (serum phosphorus, estrone, androstenedione, and urine calcium) observed during the first 6 months of the study, we have been able to correctly predict the rate of spinal bone loss, observed at the end of the 3 years, in 76% of the subjects. All of the women who presented a bone loss higher than 10% over the 3 years were correctly isolated by our discriminant functions after 6 months of follow-up. We conclude that a measurement of lumbar bone mineral density coupled with a few routine biochemical determinations, repeated twice at a 6-month interval in healthy postmenopausal women, can isolate 100% of postmenopausal "fast bone losers" with an overall specificity of 76%. [less ▲]

Detailed reference viewed: 21 (5 ULg)