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See detailFinite-element analysis of a double-winding induction motor with a special rotor bars topology
Oliveira, Ana Margarida; Kuo-Peng, Patrick; Sadowski, Nelson et al

in IEEE Transactions on Magnetics (2004), 40(2, Part 2), 770-773

A model allowing the simulation of induction machines with different rotor bars configurations is presented. The electrical machine is modeled by using two-dimensional (2-D) finite-element method and its ... [more ▼]

A model allowing the simulation of induction machines with different rotor bars configurations is presented. The electrical machine is modeled by using two-dimensional (2-D) finite-element method and its equations are directly coupled with those of the circuit. A general and new contribution is added for the consideration of special rotor bars topologies. The movement is taken into account by means of the moving band technique, the Maxwell stress tensor, and the mechanical oscillation equation. The model is applied to a brushless doubly fed induction motor. [less ▲]

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See detailFinite-Element Analysis of a Shielded Pulsed-Current Induction Heater -- Experimental Validation of a Time-Domain Thin-Shell Approach
V Sabariego, Ruth ULg; Sergeant, Peter; Gyselinck, Johan et al

in COMPEL (2010), 29(6), 1585-1595

Purpose – The aim of this paper is the experimental validation of an original time-domain thin-shell formulation. The numerical results of a three-dimensional thin-shell model are compared with the ... [more ▼]

Purpose – The aim of this paper is the experimental validation of an original time-domain thin-shell formulation. The numerical results of a three-dimensional thin-shell model are compared with the measurements performed on a heating device at different working frequencies. Design/methodology/approach – A time-domain extension of the classical frequency-domain thin-shell approach is used for the finite-element analysis of a shielded pulse-current induction heater. The time-domain interface conditions at the shell surface are expressed in terms of the average flux density vector in the shell, as well as in terms of a limited number of higher-order components. Findings – A very good agreement between measurements and simulations is observed. A clear advantage of the proposed thin-shell approach is that the mesh of the computation domain does not depend on the working frequency anymore. It provides a good compromise between computational cost and accuracy. Indeed, adding a sufficient number of induction components, a very high accuracy can be achieved. Originality/value – The method is based on the coupling of a time-domain 1D thin-shell model with a magnetic vector potential formulation via the surface integral term. A limited number of additional unknowns for the magnetic flux density are incorporated on the shell boundary. [less ▲]

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See detailFinite-Element Analysis of a Shielded Pulsed-Current Induction Heater-- Experimental Validation of a Time-Domain Thin-Shell Approach
V Sabariego, Ruth ULg; Sergeant, Peter; Gyselink, Johan et al

in Proceedings of the 8th International Symposium on Electric and Magnetic Fields (EMF2009) (2009)

A time-domain extension of the classical frequency-domain thin-shell approach is used for the finite-element analysis of a shielded pulse-current induction heater. The time-domain interface conditions at ... [more ▼]

A time-domain extension of the classical frequency-domain thin-shell approach is used for the finite-element analysis of a shielded pulse-current induction heater. The time-domain interface conditions at the shell surface are expressed in terms of the average (zero-order) instantaneous flux and current density vectors in the shell, as well as in terms of a limited number of higher-order components. The three-dimensional thin-shell model is validated by comparing the numerical results with measurements performed on the heating device at different working frequencies. [less ▲]

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See detailFinite-Element Homogenization of Laminated Iron Cores With Inclusion of Net Circulating Currents Due to Imperfect Insulation
Gyselinck, Johan; Dular, Patrick ULg; Krähenbühl, Laurent et al

in IEEE Transactions on Magnetics (2016), 52(3),

This paper deals with the time-domain homogenization of laminated cores in 2-D or 3-D finite-element (FE) models of electromagnetic devices, allowing for net circulating current in the laminations (e.g ... [more ▼]

This paper deals with the time-domain homogenization of laminated cores in 2-D or 3-D finite-element (FE) models of electromagnetic devices, allowing for net circulating current in the laminations (e.g., due to imperfect or damaged insulation). The homogenization is based on the expansion of the induction throughout the lamination thickness using a set of orthogonal polynomial basis functions (BFs), in conjunction with the magnetic vector potential formulation. These BFs allow for net flux, net current, and skin effect in the laminations; by choosing the number of BFs, one can compromise between accuracy and computational cost. The approach is validated through a linear 2-D test case with in-plane imposed and induced current density. A brute-force model, in which all laminations are finely meshed, produces the reference solution. The extension to nonlinear 3-D problems is expected to be straightforward. [less ▲]

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See detailA finite-element reciprocity solution for EEG forward modeling with realistic individual head models
Ziegler, Erik ULg; Chellappa, Sarah Laxhmi ULg; Gaggioni, Giulia ULg et al

in NeuroImage (2014), 103

Highlights • Creates EEG forward models suitable for high-resolution source localization. • Automatic T1-based whole-head finite element meshing and leadfield computation. • Pipelines can incorporate ... [more ▼]

Highlights • Creates EEG forward models suitable for high-resolution source localization. • Automatic T1-based whole-head finite element meshing and leadfield computation. • Pipelines can incorporate conductivity tensors from diffusion-weighted images. • Open-source toolbox shared under a permissive software license. • Accuracy comparable to SimBio FEM and superior to OpenMEEG BEM solutions. [less ▲]

Detailed reference viewed: 141 (27 ULg)
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See detailFinite-element simulations of cup drawing using the taylor and the lamel model
Van Bael, A.; He, S.; Van Houtte, P. et al

in Stören, Sigurd (Ed.) Proceedings of the 7th ESAFORM conference on Materials Forming (2004)

Detailed reference viewed: 21 (4 ULg)
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See detailFinite-elements design of a guarded heating cylinder to measure thermal properties of materials
Nicolas, Jacques ULg; Martin, Fabrice; Andre, Philippe ULg et al

in Review of Scientific Instruments (1990), 61

A device for the measurement of thermal properties of phase change materials and, in general, of medium thermal conductivity materials, is described. The measuring cell is a modified version of the ... [more ▼]

A device for the measurement of thermal properties of phase change materials and, in general, of medium thermal conductivity materials, is described. The measuring cell is a modified version of the guarded hot plate technique, here designed for about 8-cm-diam samples. A well-known difficulty arises in such a device: its limitation when the sample cross section becomes too small with respect to its thickness. A finite-element model is used to study the shape of isotherms in a thick sample (10 cm) for different configurations of the measuring device. This analysis has led to the selection of the optimum design. It shows that the instrument is able to handle samples with a diameter to thickness ratio of about 1 so far as the heat transfer coefficient remains beneath some limits (here 100 W/m2 K). The control system is also described and some typical results are presented. Review of Scientific Instruments is copyrighted by The American Institute of Physics. [less ▲]

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See detailFinite-size effects in BaTiO3 nanowires
Geneste, G.; Bousquet, Eric ULg; Junquera, J. et al

in Applied Physics Letters (2006), 88

The size dependence of the ferroelectric properties of BaTiO3 nanowires is studied from first principles. We show that the ferroelectric distortion along the wire axis disappears below a critical diameter ... [more ▼]

The size dependence of the ferroelectric properties of BaTiO3 nanowires is studied from first principles. We show that the ferroelectric distortion along the wire axis disappears below a critical diameter of about 1.2 nm. This disappearance is related to a global contraction of the unit cell resulting from low atomic coordinations at the wire surface. It is shown that a ferroelectric distortion can be recovered under appropriate tensile strain conditions. (c) 2006 American Institute of Physics. [less ▲]

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See detailFinitely Presented Monoids and Algebras defined by Permutation Relations of Abelian Type
Cedó, Ferran; Jespers, Eric; Klein, Georg ULg

in Journal of Pure and Applied Algebra (2012), 216

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See detailFiniteness of the weighted likelihood estimator and applications to CAT
Magis, David ULg

Scientific conference (2016, July 07)

The purpose of this talk is to present some recent research on the weighted likelihood estimator (WLE) of ability in item response theory (IRT). This estimator is quite commonly used as an alternative to ... [more ▼]

The purpose of this talk is to present some recent research on the weighted likelihood estimator (WLE) of ability in item response theory (IRT). This estimator is quite commonly used as an alternative to usual maximum likelihood and Bayesian estimators. However, the uestion of providing finite ability estimates was left unsolved and led to some controversy. Recently, Magis and Verhelst (in press) established that the WLE always returns finite values, independently of the IRT model, the number of items, and the item responses. This general result will be briefly outlined. The finiteness of the WLE has straightforward impact within the field of computerized adaptive testing (CAT). One technical and crucial issue in CAT is to accurately estimate the latent ability at the early stages of the adaptive process, when only a few items are available. Currently heuristic adjustments are adviced to avoid infinite estimates with only a few item responses. In this talk it will be highlighted how the use of the WLE throughout the CAT can be a promising and performant approach to solve this issue. [less ▲]

Detailed reference viewed: 36 (3 ULg)
See detailFins a quin punt l'alumnat immigrant és victima de segregacio escolar ? Analisi secundaria de l'estudi PISA 2000
Crahay, Marcel ULg; Monseur, Christian ULg

in In Nouvinguts, fins quan ? Ve Simposi : llengua, educacio i immigracio Coordination (2007)

Detailed reference viewed: 32 (2 ULg)
See detailLes fins du monde peuvent-elles faire littérature ? Exemplarités du récit dystopique
Stienon, Valérie ULg

Scientific conference (2014, March 27)

S’il est possible d’observer de nombreuses œuvres qui, depuis le XIXe siècle et particulièrement au tournant du XXe siècle, se présentent comme des fictions de fins du monde déclinant les situations ... [more ▼]

S’il est possible d’observer de nombreuses œuvres qui, depuis le XIXe siècle et particulièrement au tournant du XXe siècle, se présentent comme des fictions de fins du monde déclinant les situations-catastrophes, il est plus difficile d’appréhender ces textes en mots et en images comme un ensemble cohérent et de les associer à un genre littéraire particulier. Entre désignations d’époque et catégorisations rétrospectives, un corpus se dessine toutefois, qui développe ses propres caractéristiques internes et connaît une histoire éditoriale complexe. La communication propose de réfléchir aux modalités d’appartenance de ces « récits dystopiques » à l’histoire littéraire et aux critères possibles de leur rassemblement pour une étude poétique transversale. [less ▲]

Detailed reference viewed: 64 (2 ULg)
See detailFiona Templeton
Delville, Michel ULg

in Shelton, Pamela (Ed.) Contemporary Women Poets (1997)

Detailed reference viewed: 26 (1 ULg)
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See detailFIPA : étude clinique et génétique à l'Hôpital "King Edward Memorial", Bombay (Mumbai) Inde
Bothra, N; Daly, Adrian ULg; CASTERMANS, Emilie ULg et al

in Annales d'Endocrinologie (2013, October), 74

Detailed reference viewed: 26 (10 ULg)
See detailFIPA et mutations dans le gène AIP
Beckers, Albert ULg

Scientific conference (2006, December 15)

Detailed reference viewed: 18 (3 ULg)
See detailFire action and design approach
Franssen, Jean-Marc ULg; Dotreppe, Jean-Claude ULg; Both, K. et al

in Fire design of concrete structures - structural behaviour and assessment. State-of-art report. (2008)

Detailed reference viewed: 61 (6 ULg)