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See detailModeling and simulation of the domestic energy use in Belgium following a bottom-up approach
Georges, Emeline ULg; Gendebien, Samuel ULg; Bertagnolio, Stéphane ULg et al

in Proceedings of the CLIMA 2013 11th REHVA World Congress & 8th International Conference on IAQVEC (2013, June)

The present paper presents a “bottom-up” approach dedicated to the modeling and simulation of the domestic energy use. This methodology focuses first on a microanalysis (i.e. modeling and simulation of a ... [more ▼]

The present paper presents a “bottom-up” approach dedicated to the modeling and simulation of the domestic energy use. This methodology focuses first on a microanalysis (i.e. modeling and simulation of a set of representative households). Results from this micro-analysis are then used and extended to allow drawing conclusions at a macro-scale. The methodology can be validated by comparing simulation results to annual national energy consumption indexes or synthetic load profiles (energy consumption profiles generated from values of predefined past periods). Once the method is validated, it can be used to study the impact of different retrofit scenarios on the annual energy use and on the energy demand profiles. This paper describes the methodology developed for Belgium. [less ▲]

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See detailModeling and Uncertainty Quantification of Thermoelastic Damping in Micro-Resonators
Lepage, Séverine; Golinval, Jean-Claude ULg

Conference given outside the academic context (2006)

In the design of micro-electromechanical systems (MEMS) such as micro-resonators, dissipation mechanisms may have detrimental effects on the quality factor, which is directly related to the response ... [more ▼]

In the design of micro-electromechanical systems (MEMS) such as micro-resonators, dissipation mechanisms may have detrimental effects on the quality factor, which is directly related to the response amplitude of the system that is excited at its natural frequency. One of the major dissipation phenomena to be considered in such micro-systems is thermoelastic damping. Hence, the performance of such MEMS is directly related to their thermoelastic quality factor which has to be predicted accurately. Moreover, the performance of MEMS depends on manufacturing processes which may cause substantial uncertainty in the geometry and in the material properties of the device. The reliability of MEMS devices is affected by the inability to accurately predict the behavior of the system due to the presence of these uncertainties. The aim of this paper is to provide a framework to account for uncertainties in the finite element analysis. Particularly, the influence of uncertainties on the performance of a micro-beam is studied using Monte- Carlo simulations. A random field approach is used to characterize the variation of the material as well as the geometric properties. Their effects on the thermoelastic quality factor of a micro-beam are studied. [less ▲]

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See detailA modeling approach to determine the contribution of plant hydraulic conductivities on the water uptake dynamics in the soil-plant-atmosphere system
Lobet, Guillaume ULg; Pagès, Loïc; Draye, Xavier

in Plant Growth Modeling, Simulation, Visualization and Applications (PMA), 2012 IEEE Fourth International Symposium on (2012)

Detailed reference viewed: 14 (2 ULg)
See detailModeling argon dynamics in first-year sea ice
Moreau, S.; Vancoppenolle, M.; Tison, J.-L. et al

Poster (2012, July)

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See detailModeling astatine production in liquid lead-bismuth spallation targets
David, J.-C.; Boudard, A.; Cugnon, Joseph ULg et al

in European Physical Journal A -- Hadrons & Nuclei (2013), 49

Detailed reference viewed: 38 (16 ULg)
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See detailModeling Biogeochemical Processes in Marine Ecosystems
Grégoire, Marilaure ULg; Oguz, Temel

in Nihoul, Jacques; Chen, Arthur (Eds.) the Unesco Encyclopedia of Life Support Systems (2005)

Detailed reference viewed: 22 (1 ULg)
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See detailModeling cell/matrix growth in three dimensional scaffolds under dynamic culture conditions
Guyot, Yann ULg; Papantoniou, Ioannis; Chai, Yoke Chin et al

Conference (2013, October)

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See detailModeling climate change impacts on groundwater resources using transient stochastic climatic scenarios
Goderniaux, Pascal ULg; Brouyère, Serge ULg; Blenkinsop, Stephen et al

in Water Resources Research (2011), 47

Several studies have highlighted the potential negative impact of climate change on groundwater reserves but additional work is required to help water managers to plan for future changes. In particular ... [more ▼]

Several studies have highlighted the potential negative impact of climate change on groundwater reserves but additional work is required to help water managers to plan for future changes. In particular, existing studies provide projections for a stationary climate representative of the end of the century, although information is demanded for the near-future. Such time-slice experiments fail to account for the transient nature of climatic changes over the century. Moreover, uncertainty linked to natural climate variability is not explicitly considered in previous studies. In this study, we substantially improve upon the state-of-the-art by using a sophisticated transient weather generator (WG) in combination with an integrated surface-subsurface hydrological model (Geer basin, Belgium) developed with the finite element modelling software 'HydroGeoSphere'. This version of the WG enables the stochastic generation of large numbers of equiprobable climatic time series, representing transient climate change, and used to assess impacts in a probabilistic way. For the Geer basin, 30 equiprobable climate change scenarios from 2010 to 2085 have been generated for each of 6 different RCMs. Results show that although the 95% confidence intervals calculated around projected groundwater levels remain large, the climate change signal becomes stronger than that of natural climate variability by 2085. Additionally, the WG ability to simulate transient climate change enabled the assessment of the likely timescale and associated uncertainty of a specific impact, providing managers with additional information when planning further investment. This methodology constitutes a real improvement in the field of groundwater projections under climate change conditions. [less ▲]

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See detailModeling Daily Traffic Counts: Analyzing the Effects of Holidays
Cools, Mario ULg; Moons, Elke; Wets, Geert

in Sloboda, Brian (Ed.) Transportation Statistics (2009)

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See detailModeling frictional contact conditions with the penalty method in the extended finite element framework
Biotteau, Ewen ULg; Ponthot, Jean-Philippe ULg

Scientific conference (2012, September 12)

This paper introduces an application of the eXtended Finite Element Method (XFEM) to model metal forming processes. The X-FEM is used to account for material interfaces and reduce the meshing constraints ... [more ▼]

This paper introduces an application of the eXtended Finite Element Method (XFEM) to model metal forming processes. The X-FEM is used to account for material interfaces and reduce the meshing constraints due to the shape of the tools and the evolving configuration of the structures. Large deformations and non-linear behaviors are also accounted for, but this contribution focuses in the modeling of frictional conditions on the interface. In X-FEM simulations, the constraint of impenetrability is usually imposed using Lagrange multiplier methods. For such strategies, stabilisation algorithms are needed to prevent the apparition of instabilities due to the introduction of dual unknowns. The strategy presented here proposes to manage the contact using the penalty approach. As it requires no additional variables, it is not submitted to the same kind of instabilities. The contact problem is modeled using integration sub-elements, defined on the boundary of the structure, on which the contact constraints have to be enforced. [less ▲]

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See detailModeling groundwater with ocean and river interaction
Carabin, Guy; Dassargues, Alain ULg

in Water Resources Research (1999), 35(8), 2347-2358

We develop and implement the groundwater model, Saturated/Unsaturated Flow and Transport in 3D (SUFT3D), to integrate water quantity/quality data and simulations with models of other hydrologic cycle ... [more ▼]

We develop and implement the groundwater model, Saturated/Unsaturated Flow and Transport in 3D (SUFT3D), to integrate water quantity/quality data and simulations with models of other hydrologic cycle components, namely, rivers and the ocean. This work was done as part of the Sea Air Land Modeling Operational Network (SALMON) project supported by the IBM International Foundation through its Environmental Research Program. The first research steps, presented here, address the simulation of typical hydrologic conditions to demonstrate SUFT3D's effectiveness and accuracy. The theory behind the modeling of seawater intrusion and groundwater-river interaction is summarized along with the numerical methods and characteristics of SUFT3D. The code was applied to different, increasingly complex scenarios: confined to unconfined conditions, local to regional scale, homogeneous to increasing heterogeneity, two- to three-dimensional. Of particular interest were the impacts of different boundary conditions and influence of river interactions on seawater intrusion. Results are illustrated, discussed, and compared, when possible, to those in the literature. Simulating groundwater exchange between both the river and the ocean has provided interesting results that better depict the dynamics of flow and transport in coastal zone groundwater systems. [less ▲]

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See detailModeling information sharing in animal health surveillance with social network analysis
Delabouglise, Alexis; Dao Thi, Hiep; Nguyen Tien, Thanh et al

Poster (2014, May 08)

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See detailModeling lactation curves and estimation of genetic parameters for first lactation test-day records of French Holstein cows.
Druet, Tom ULg; Jaffrezic, F.; Boichard, D. et al

in Journal of Dairy Science (2003), 86(7), 2480-90

Several functions were used to model the fixed part of the lactation curve and genetic parameters of milk test-day records to estimate using French Holstein data. Parametric curves (Legendre polynomials ... [more ▼]

Several functions were used to model the fixed part of the lactation curve and genetic parameters of milk test-day records to estimate using French Holstein data. Parametric curves (Legendre polynomials, Ali-Schaeffer curve, Wilmink curve), fixed classes curves (5-d classes), and regression splines were tested. The latter were appealing because they adjusted the data well, were relatively insensitive to outliers, were flexible, and resulted in smooth curves without requiring the estimation of a large number of parameters. Genetic parameters were estimated with an Average Information REML algorithm where the average information matrix and the first derivatives of the likelihood functions were pooled over 10 samples. This approach made it possible to handle larger data sets. The residual variance was modeled as a quadratic function of days in milk. Quartic Legendre polynomials were used to estimate (co)variances of random effects. The estimates were within the range of most other studies. The greatest genetic variance was in the middle of the lactation while residual and permanent environmental variances mostly decreased during the lactation. The resulting heritability ranged from 0.15 to 0.40. The genetic correlation between the extreme parts of the lactation was 0.35 but genetic correlations were higher than 0.90 for a large part of the lactation. The use of the pooling approach resulted in smaller standard errors for the genetic parameters when compared to those obtained with a single sample. [less ▲]

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See detailModeling Lymphangiogenesis in a three-dimensional culture system
Bruyere, Françoise; Melen-Lamalle, Laurence; Blacher, Silvia ULg et al

in Nature Methods (2008), 5(5), 431-437

Unraveling the molecular mechanisms of lymphangiogenesis is hampered by the lack of appropriate in vitro models of three-dimensional (3D) lymph vessel growth which can be used to exploit the potential of ... [more ▼]

Unraveling the molecular mechanisms of lymphangiogenesis is hampered by the lack of appropriate in vitro models of three-dimensional (3D) lymph vessel growth which can be used to exploit the potential of available transgenic mice. We developed a potent reproducible and quantifiable 3D-culture system of lymphatic endothelial cells, the lymphatic ring assay, bridging the gap between 2D-in vitro and in vivo models of lymphangiogenesis. Mice thoracic duct fragments are embedded in a collagen gel leading to the formation of lymphatic capillaries containing a lumen as assessed by electron microscopy and immunostaining. This assay phenocopies the different steps of lymphangiogenesis, including the spreading from a preexisting vessel, cell proliferation, migration and differentiation into capillaries. Our study provides evidence for the implication of an individual matrix metalloproteinase, MMP-2, during lymphangiogenesis. The lymphatic ring assay is a robust, quantifiable and reproducible system which offers new opportunities for rapid identification of unknown regulators of lymphangiogenesis. [less ▲]

Detailed reference viewed: 133 (25 ULg)
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See detailModeling medium-scale TEC structures observed by Belgian GPS receivers network
Kutiev, Ivan; Marinov, Pencho; Fidanova, Stefka et al

in Advances in Space Research (2009), 43

Detailed reference viewed: 33 (4 ULg)
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See detailModeling Microbial Cross-contamination in Quick Service Restaurants by Means of Experimental Simulations With Bacillus Spores
Baptista Rodrigues, Ana Lúcia ULg; Crevecoeur, Sébastien ULg; Dure, Remi et al

Poster (2010)

Cross contamination has been frequently mentioned as being in the origin of a wide range of food borne outbreaks. Handling of food is one of the ways through which cross contamination may occur. For many ... [more ▼]

Cross contamination has been frequently mentioned as being in the origin of a wide range of food borne outbreaks. Handling of food is one of the ways through which cross contamination may occur. For many different reasons, quick service restaurants are particularly at risk. Due to its importance, cross contamination via the hands should be taken into consideration when carrying out a quantitative risk assessment. The main goal of this study was to determine transfer rates of bacteria to and via the hands, reduction rates of two hand sanitizing procedures and to apply the results to a quantitative microbial risk assessment model. According to our results, handling of a portion of raw minced meat contaminated at 4.104 cfu leads to the presence of 24 cfu on both hands, 3 cfu on ready-to-eat product (RTE) manipulated with unwashed hands, 1 cfu on RTE manipulated with wiped hands and absence on RTE manipulated with washed hands. This study provides adequate quantitative data for quantitative microbial risk assessment. [less ▲]

Detailed reference viewed: 67 (4 ULg)