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See detailApplication of the fast multipole method to hybrid finite element-boundary element models
V Sabariego, Ruth ULg; Gyselinck, Johan; Geuzaine, Christophe ULg et al

in Journal of Computational & Applied Mathematics (2004), 168(1-2), 403-412

This paper focuses on the acceleration of the hybrid finite element-boundary element analysis of 2D eddy current problems by means of the fast multipole method. An adaptive truncation scheme for the ... [more ▼]

This paper focuses on the acceleration of the hybrid finite element-boundary element analysis of 2D eddy current problems by means of the fast multipole method. An adaptive truncation scheme for the expansion of the 2D Laplace Green function is proposed. A linear time harmonic test case is considered. The results obtained with the hybrid model, with and without fast multipole acceleration, agree well with those obtained with a finite element model. The computational cost of the three calculations is compared and discussed. The proposed adaptive truncation scheme significantly contributes to the computation time savings achieved with the fast multipole method, particularly when dealing with moderate sized problems. (C) 2003 Elsevier B.V. All rights reserved. [less ▲]

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See detailApplication of the fast multipole method to the 2D finite element-boundary element analysis of electromechanical devices
V Sabariego, Ruth ULg; Gyselinck, J.; Geuzaine, Christophe ULg et al

in Proceedings of the 10th International Symposium on Numerical Field Calculation in Electrical Engineering (IGTE 2002) (2002)

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See detailApplication of the fast multipole method to the 2D finite element-boundary element analysis of electromechanical devices
V Sabariego, Ruth ULg; Gyselinck, J.; Geuzaine, Christophe ULg et al

in COMPEL (2003), 22(3), 659-673

The present paper deals with the fast multipole acceleration of the 2D finite element-boundary element modelling of electromechanical devices. It is shown that the fast multipole method, usually applied ... [more ▼]

The present paper deals with the fast multipole acceleration of the 2D finite element-boundary element modelling of electromechanical devices. It is shown that the fast multipole method, usually applied to large 3D problems, can also lead to a reduction in computational time when dealing with relatively small 2D problems, provided that an adaptive truncation scheme for the expansion of the 2D Laplace Green function is used. As an application example, the 2D hybrid modelling of a linear actuator is studied, taking into account saturation, the voltage supply and the mechanical equation. The computational cost without and with fast multipole acceleration is discussed for both the Linear and nonlinear case. [less ▲]

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See detailApplication of the Galileo system for a better synchronization of electrical power systems
Mack, Philippe; Capitanescu, Florin ULg; Glavic, Mevludin et al

(2007, July)

In this paper we present objectives and strategies of the NAVELEC research project funded by the European Union Galileo Joint Undertaking (GJU/05/2423). The project objective is to assess how the European ... [more ▼]

In this paper we present objectives and strategies of the NAVELEC research project funded by the European Union Galileo Joint Undertaking (GJU/05/2423). The project objective is to assess how the European Global Navigation Satellite System related solutions can enhance the operation and control of the European power system over wide areas. Some basic functionalities of the GALILEO system are given first, then we summarize the questionnaire, set at the initial stage of the project, and provide the analysis of received responses from transmission system operators. Two generic strategies to upgrade existing electrical power transmission networks with functionalities, as well as major steps to upgrade underlying infrastructures, are discussed in this paper. [less ▲]

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See detailApplication of the GHER 3D general circulation model to the Western Mediterranean
Beckers, Jean-Marie ULg

in Journal of Marine Systems (1991), 1(4), 315-332

The GHER 3D k− OGCM is briefly described and its application to the Western Mediterranean Sea's specifities is discussed. The simulation of the Western Mediterranean General Circulation in typical winter ... [more ▼]

The GHER 3D k− OGCM is briefly described and its application to the Western Mediterranean Sea's specifities is discussed. The simulation of the Western Mediterranean General Circulation in typical winter conditions shows that the model is able to reproduce the main physical processes and the main trends of the general circulation. However, the detailed current patterns appears too sensitive to the choice of initial conditions and a better knowledge of these conditions is required for further routine forecasts. [less ▲]

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See detailApplication of the Gini index to measure the concentration on several agricultural international markets
Burny, Philippe ULg; Lebailly, Philippe ULg

in Tropicultura (1986), 6(4), 163-166

This paper studies the level of concentration of several agricultural products exports whose roles are important in developing countries. The Gini index was determined as it measures the level of ... [more ▼]

This paper studies the level of concentration of several agricultural products exports whose roles are important in developing countries. The Gini index was determined as it measures the level of competition within the different markets. After a description of the index, eight products were studied : bovine meat, poultry meat, eggs in the shell, rice, sugar, tea, rubber and palm oil. For each of them, the Gini index was calculated according to the data of the Food and Agriculture Organization in 1965, 1970, 1975, 1980 and 1985. A comparison was made between the years 1965 and 1985 in order to show the evolution of the relative importance of the different exporting countries. ln conclusion, the successes, failures or changing goals of the agricultural policy of these countries could be evaluated. [less ▲]

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See detailApplication of the HFEMC method to an abandoned coalfield in Belgium: From conceptualisation to scenario simulations
Wildemeersch, Samuel ULg; Brouyère, Serge ULg; Orban, Philippe ULg et al

Conference (2009, October 20)

The Hybrid Finite Element Mixing Cell (HFEMC) method is a flexible modelling technique particularly suited to mining context (Brouyère et al., 2009). The principle of this method is to subdivide the ... [more ▼]

The Hybrid Finite Element Mixing Cell (HFEMC) method is a flexible modelling technique particularly suited to mining context (Brouyère et al., 2009). The principle of this method is to subdivide the modelled zone into several subdomains and to select a specific equation, ranging from the simple linear reservoir equation to the groundwater flow in porous media equation, to model groundwater flow in each subdomain. The model can be run in transient conditions, which makes it a useful tool for managing mine closure post-issues such as groundwater rebound and water inrushes. An application of the HFEMC method to an abandoned underground coal mine near the city of Liège (Belgium) is presented. The case study zone has been discretized taking advantage of the flexibility of the method. Then, the model has been calibrated in both steady-state and transient flow regimes based on hydraulic head and water discharge rate observations. Finally, the calibrated model has been used to run several scenarios in order to assess the impacts of possible future phenomena on the hydraulic heads and the water discharge rates. Among others, the simulation of a strong rainfall event shows a quick and strong increase in hydraulic heads in some exploited zones coupled with a strong increase in associated water discharge rates. This could lead to stability problems in the hill slopes near the exploited zones. This kind of predictions can greatly help managing and predicting mine water problems in this particularly complex mining system. [less ▲]

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See detailApplication Of The Hough Transform For Seed Row Localisation Using Machine Vision
Leemans, Vincent ULg; Destain, Marie-France ULg

in Biosystems Engineering (2006), 94(3),

This paper compares two methods based on machine vision to provide driver assistance in seed drill guidance in order to improve spacing accuracy during contiguous passages. The first case consisted of ... [more ▼]

This paper compares two methods based on machine vision to provide driver assistance in seed drill guidance in order to improve spacing accuracy during contiguous passages. The first case consisted of following the furrow created at the preceding passage by a special marker disc attached to the seed drill. A camera was located on the tractor and detected this furrow. In the second case, the seed rows themselves were detected by the camera without making use of the marker disc. In both cases, several video sequences were acquired in various situations, including different soil textures and various illumination conditions (375 sequences were acquired during three years). A pre-treatment of these sequences was performed and included a background subtraction in order to remove shadows and other wide unevenness. In the first case, the best results were obtained by using an image treatment based on the Hough transform coupled to a recursive filter. The search of the maximum of the Hough transform was performed using a mean shift algorithm. In the second case, where several parallel rows were simultaneously present on the images, an adapted Hough transform was proposed which took into account the a priori knowledge of the rows spacing. The trueness and precision in row detection were superior in the second case. The results are compatible with the application, since the trueness was smaller than 30 mm. This suggested that it can be possible to assist the manual guidance of a seed drill by an automatic system consisting in a camera detecting the seed rows. [less ▲]

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See detailApplication of the Hybrid Finite Element Mixing Cell method to an abandoned coalfield in Belgium
Wildemeersch, Samuel ULg; Brouyère, Serge ULg; Orban, Philippe ULg et al

in Journal of Hydrology (2010), 392(3-4), 188-200

The Hybrid Finite Element Mixing Cell (HFEMC) method is a flexible modelling technique particularly suited to mining problems. The principle of this method is to subdivide the modelled zone into several ... [more ▼]

The Hybrid Finite Element Mixing Cell (HFEMC) method is a flexible modelling technique particularly suited to mining problems. The principle of this method is to subdivide the modelled zone into several subdomains and to select a specific equation, ranging from the simple linear reservoir equation to the groundwater flow in porous media equation, to model groundwater flow in each subdomain. The model can be run in transient conditions, which makes it a useful tool for managing mine closure post-issues such as groundwater rebound and water inrushes. The application of the HFEMC method to an abandoned underground coal mine near the city of Liege (Belgium) is presented. The case study zone has been discretized taking advantage of the flexibility of the method. Then, the model has been calibrated in transient conditions based on both hydraulic head and water discharge rate observation and an uncertainty analysis has been performed. Finally, the calibrated model has been used to run several scenarios in order to assess the impacts of possible future phenomena on the hydraulic heads and the water discharge rates. Among others, the simulation of an intense rainfall event shows a quick and strong increase in hydraulic heads in some zones coupled with an increase in associated water discharge rates. This could lead to stability problems in local hill slopes. These predictions will help managing and predicting mine water problems in this complex mining system. [less ▲]

Detailed reference viewed: 102 (45 ULg)
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See detailApplication of the laser beam deflection to the study of temperature filed and heat transfer in natural convection,
Cerisier, P.; Sylvain, J. D.; Dauby, Pierre ULg

in Experiments in Fluids (2002), 33

Detailed reference viewed: 10 (0 ULg)
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See detailApplication of the laser deflection to the study of temperature fields in two-dimensional flows
Cerisier, P.; Dauby, Pierre ULg

in Proceedings of the VI International science-technical conference, Optical methods of flows investigation (2001)

Detailed reference viewed: 5 (0 ULg)
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See detailApplication of the Lempel-Ziv complexity to the alignment-free sequence comparison of protein families
Bacha, Sofiène; Baurain, Denis ULg

Scientific conference (2005, August 26)

Detailed reference viewed: 22 (4 ULg)
See detailApplication of the macromolecular engineering to the nanotechnology
Detrembleur, Christophe ULg

Conference (2005, May 11)

Detailed reference viewed: 7 (2 ULg)
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See detailApplication of the morphological acceleration factor in fluvial hydraulics
Dewals, Benjamin ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in E-proceedings of the 36th IAHR World Congress (2015, June)

The morphological acceleration factor (Morfac) has been widely used to speed-up morphodynamic simulations, mostly in coastal applications. The value of Morfac was generally set by trial and error and ... [more ▼]

The morphological acceleration factor (Morfac) has been widely used to speed-up morphodynamic simulations, mostly in coastal applications. The value of Morfac was generally set by trial and error and little theoretical background is available to identify an optimal value of Morfac for a given application and a target level of accuracy. In the present research, we generalize the few previous theoretical analyses regarding two main aspects. First, the range of the considered parameters (Froude number, relative roughness, transport rate …) has been considerably extended to cover typical values characterizing fluvial applications and not only coastal settings. Second, we show that the optimal value of Morfac depends greatly on the specific mathematical formulation of the flow model and on the flow regime. [less ▲]

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See detailApplication of the new Eurocode 3 beam-column formulae to tubular construction
Ly, L; Jaspart, Jean-Pierre ULg; Weynand, K

Scientific conference (2010, December)

New design formulae for the stability of structural members subjected to combined bending moments and axial forces (so-called beam-columns) have been recently developed and included in the EN version of ... [more ▼]

New design formulae for the stability of structural members subjected to combined bending moments and axial forces (so-called beam-columns) have been recently developed and included in the EN version of the European Norm Eurocode 3 Part 1-1 (EC3). It has however to be recognized that these formulae have been validated mostly through comparisons with results of experimental tests and numerical simulations carried out on columns with open sections. The question may therefore be raised to know whether the new formulae are adapted to tubular columns with a similar degree of accuracy and safety than for open section columns. The aim of the paper is to indicate how present EC3 formulae fit with the available results on tubular columns, and then to suggest improvements of the formulae when applied to the latter. [less ▲]

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See detailThe application of the NSGA-II optimization method in designing control charts
Faraz, Alireza ULg; Heuchenne, Cédric ULg; Seif, Asghar

Conference (2014, June 04)

The problem of designing control chart is formulated as a multi-objective optimization problem with the adjusted average time to signal as the statistical objective and the expected cost per hour as the ... [more ▼]

The problem of designing control chart is formulated as a multi-objective optimization problem with the adjusted average time to signal as the statistical objective and the expected cost per hour as the economic objective. Then we try to find the Pareto-optimal designs in which the two objectives are minimized simultaneously by using the elitist non-dominated sorting genetic algorithm method. Through an illustrative example, the advantages of the proposed approach is shown by providing a list of viable optimal solutions and graphical representations, thereby bolding the advantage of flexibility and adaptability. [less ▲]

Detailed reference viewed: 32 (3 ULg)