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See detailPredicting the spatial distribution of population based on impervious surface maps and modeled land use change
Cornet, Yves ULg; Binard, Marc ULg; Ledant, Martin et al

in Perakis, Konstantinos G.; Moysiadis, Athanasios K. (Eds.) European Association of Remote Sensing Laboratories 32nd EARSeL Symposium Proceedings Advances in Geosciences Mykonos Island, Greece, 21 May - 24 May 2012 (2012)

Land use and changes in the spatial distribution of population are spatially and temporally linked and have an obvious impact on the urban environment. For instance, they influence the mobility and ... [more ▼]

Land use and changes in the spatial distribution of population are spatially and temporally linked and have an obvious impact on the urban environment. For instance, they influence the mobility and accessibility and play an important role in waste water management. This forecasting of the spatial distribution of population is thus a critical issue in planning. In order to allow this forecasting we have adjusted a multiple regression model to estimate the population distribution in function of land-use. The originality in our modeling strategy is the use of sealed surface proportion maps as weighting factor assuming that sealed surface proportion is a proxy of population density. The data exploited to adjust the parameters of the model are three time-series of landuse maps from the EU-MOLAND, census data and medium and high resolution remotely sensed images. We made use of these images in a spectral unmixing procedure that provides the sealed surface proportion maps. In the model, the population was normalized in order to get a model that is independent of time and space. This is required for prediction and spatial extrapolation which assumes a temporally and spatially stable relationship between land use, imperviousness and population density. We validated the model by means of a population disaggregation/re-aggregation procedures and tested its robustness regarding the resolution because predicted sealed surface proportion and predicted landuse maps using the calibrated EU-MOLAND model are generated at lower resolution (200 m) than the resolution used in the model adjustment. The results described in this paper regard the urban zone of Dublin. [less ▲]

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See detailPredicting the transverse volume distribution under an agricultural spray boom
Leunda, P.; Debouche, Charles ULg; Caussin, R.

in Crop Protection (1990), 9(2), 111-114

The volume distribution of spray below individual agricultural flat-fan spray nozzles was fitted to a truncated normal distribution. This expresses the parameters as a function of the spray liquid ... [more ▼]

The volume distribution of spray below individual agricultural flat-fan spray nozzles was fitted to a truncated normal distribution. This expresses the parameters as a function of the spray liquid pressure, the boom height and the nozzle orifice size. This model was used to predict the transverse distribution below an agricultural spray boom. [less ▲]

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See detailPredicting transpiration from forest stands in Belgium for the 21st century
Misson, Laurent; Rasse, Daniel; Vincke, Caroline et al

in Agricultural and Forest Meteorology (2002), 111(4), 265-282

Canopy transpiration is a major element of the hydrological cycle of temperate forests. Levels of water stress during the 21st century will be largely controlled by the response of canopy transpiration to ... [more ▼]

Canopy transpiration is a major element of the hydrological cycle of temperate forests. Levels of water stress during the 21st century will be largely controlled by the response of canopy transpiration to changing environmental conditions. One year of transpiration measurement in two stands (Quercus robur L. and Fagus sylvatica L.) was used to calibrate the ASPECTS model on a(1) and D-0, two parameters of a modified version of Leuning's equation of stomatal conductance. A second year of data was used to validate the model. The results indicate a higher sensitivity of g(sc), to vapour pressure deficit (DS) in oak than in beech (D-0 (oak) < D-0 (beech)). To simulate future forest transpiration, site specific weather data sets were constructed from GCM outputs, spatially and temporally downscaled with local climatic data. Temperature increase between the end of the 20th and 21st centuries was predicted to be 2.8 degreesC in the beech stand and 3.1 degreesC in the oak stand. Based solely on temperature change, ASPECTS predicted an increase in transpiration of 17% in the beech and 6% in the oak stand, the difference being due to variation in local climate and the sensitivity of both species to D-s. Based solely on increased atmospheric CO2 (355 ppm in 1990 to 700 ppm in 2100), ASPECTS predicted that transpiration would decrease by 22% in beech and 19% in oak. With the combined scenarios of climatic change and increased atmospheric CO2, ASPECTS showed a decrease of 7% in transpired water in the oak stand and only 4% in the beech stand, which are not significant differences from zero. Consequently, water stress should not increase in either stand during the 21st century. (C) 2002 Elsevier Science B.V All rights reserved. [less ▲]

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See detailPrediction and measurement of the random incidence scattering coefficient of periodic reflective rectangular diffuser profiles
Schmich-Yamane, Isabelle; Embrechts, Jean-Jacques ULg; Müller-Trapet, Markus et al

in Proceedings of the 2013 ICA Congress (2013, June)

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See detailPrédiction de l'érosion ravinante en Algérie : vers une nouvelle approche probabiliste à l'aide de données multisources.
Daoudi, Mohamed; Salmon, Marc ULg; Dewitte, Olivier et al

in Journées d’Animation Scientifique (JAS09) de l’AUF (2009, November)

Pour faire face à la complexité de l'érosion ravinante dans la région tellienne, le présent travail propose l'utilisation d'une approche probabiliste basée sur des données multisources dont les images de ... [more ▼]

Pour faire face à la complexité de l'érosion ravinante dans la région tellienne, le présent travail propose l'utilisation d'une approche probabiliste basée sur des données multisources dont les images de télédétection. Un modèle de régression logistique a été élaboré pour la prédiction du processus de ravinement dans le bassin versant de l'oued Isser. Dans un premier temps, il expose les facteurs contrôlant l'érosion linéaire et dans un deuxième temps, il génère des cartes prédictives des zones propices au ravinement. [less ▲]

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See detailPrédiction de la composition de la carcasse et de la qualité de viande du Piétrain stress négatif par ultrasonographie en temps réel
Youssao, A. K. I.; Verleyen, Vincent ULg; Michaux, Charles ULg et al

in Annales de Médecine Vétérinaire (2003), 147(6), 403-410

The lean meat proportion and longissimus thoracis intramuscular fat percentage were predicted in negative-stress Pietrain pigs by real-time ultrasound using Pie Medical 200. The optimal probing site for ... [more ▼]

The lean meat proportion and longissimus thoracis intramuscular fat percentage were predicted in negative-stress Pietrain pigs by real-time ultrasound using Pie Medical 200. The optimal probing site for the estimation of carcass lean content percentage was first identified. The models for the prediction of carcass lean content proportion by ultrasound measurement were developed. Comparisons between Fat Lean Meter, ultrasonic device Piglog 105 and Pie Medical 200 were made for lean meat proportion estimation in Pietrain carcasses. The intramuscular fat percentage was predicted from the white pixel percentage in the longissimus thoracis ultrasound image [less ▲]

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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 ▲]

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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 ▲]

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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)

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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 ▲]

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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)

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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.

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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)