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See detailOptimal synthesis of mechanisms using time-varying dimensions and natural coordinates
Collard, Jean-François; Fisette, Paul; Duysinx, Pierre ULg

in Herskowitz, José (Ed.) Proceedings of the 6th World Congress of Structural and Multidisciplinary Optimization (WCSMO6) (2005, June)

This paper presents a simple approach to optimize the dimensions and the positions of 2D mechanisms for path or function-generator synthesis. The proposed method is particularly adapted to assembled ... [more ▼]

This paper presents a simple approach to optimize the dimensions and the positions of 2D mechanisms for path or function-generator synthesis. The proposed method is particularly adapted to assembled mechanisms since time-varying dimensions always satisfy the assembly conditions which may represent a real difficulty when dealing with closed-loop mechanisms. The objective is to minimize the strain energy of the bars - considered as flexible - of the mechanism when this one follows perfectly the desired path. Two optimization strategies are developed and criticized. The first one is based on separated optimizations of design parameters and point coordinates. The second one is more global and is performed in two stages : multiple local synthesis are needed first to find the initial point coordinates, and then a global synthesis stage is undertaken to find both the best dimensions and coordinates. The use of natural coordinates is also particularly interesting since the only non linear functions to optimize are distance functions, and the objective function is rather well-conditioned for a gradient-based optimizer. The question of finding the global optimum is addressed and discussed. Since a standard genetic algorithm may fail to find it, a different approach is proposed: exploring the design space to find several local optima among which the designer will choose the most relevant one taking other design constraints into account. A simple technique is applied which consists in running multiple optimization processes starting from uniformly-distributed initial dimensions (full-factorial design of experiments) across the parameter space. Three applications are presented: a simple four-bar path synthesis to illustrate the optimization strategies, a four-bar steering linkage synthesis for function generation – Ackermann relation to highlight the limits of both strategies, and eventually a six-bar steering mechanism to explore the design space and find different local optima. [less ▲]

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See detailWhole-body barometric plethysmography in healthy dogs : influence of jet nebulizer and bias flow rate on the results of a bronchoprovocative test
Talavera, J.; Bernaerts, Frederique ULg; Schuller, S. et al

in ACVIM Meeting - Baltimore (USA) - juin 2005 (2005, June)

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See detailA unified finite element framework for the dynamic analysis of controlled flexible mechanisms
Bruls, Olivier ULg; Duysinx, Pierre ULg; Golinval, Jean-Claude ULg

in Proceedings of the ECCOMAS Conference on Advances in Computational Multibody Dynamics (2005, June)

This paper proposes a unified formalism for the simulation of mechatronic systems with complex flexible mechanisms. The equations of motion are formulated using a nonlinear Finite Element approach for the ... [more ▼]

This paper proposes a unified formalism for the simulation of mechatronic systems with complex flexible mechanisms. The equations of motion are formulated using a nonlinear Finite Element approach for the mechanism, and the block diagram language for the control system. The set of strongly coupled equations of motion is constructed numerically, and integrated in the time domain using the generalized-alpha method. Convergence and stability properties are thus guaranteed for the simulation algorithm. Two illustrative examples are treated in the fields of vehicle dynamics and robotics respectively. [less ▲]

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See detailQuasi steady-state models for long-term voltage and frequency dynamics simulation
Grenier, Marie-Eve; Lefebvre, Daniel; Van Cutsem, Thierry ULg

in Proc. IEEE Power Tech conference (2005, June)

The Quasi Steady-State (QSS) approximation of long-term dynamics relies on time-scale decomposition and consists of replacing faster phenomena by their equilibrium conditions, in order to reduce the ... [more ▼]

The Quasi Steady-State (QSS) approximation of long-term dynamics relies on time-scale decomposition and consists of replacing faster phenomena by their equilibrium conditions, in order to reduce the complexity of the whole model and increase the computation efficiency of time simulations. This paper describes the extension of a QSS model extensively used in long-term voltage stability studies, to readily incorporate the frequency dynamics that takes place over the same time scale. This extended QSS model relies on a common-frequency assumption. Its advantages, limitations and possible improvements are discussed through simulation results on the Hydro-Québec system, where it has been compared to full time scale simulations. Disturbances with an impact on either frequency or voltages are considered and the coupling between these two aspects of long-term dynamics is briefly discussed. [less ▲]

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See detailFlutter Clearance of a Non-linear aircraft
Benini, Guilherme; Vio, Gareth Arthur; Dimitriadis, Grigorios ULg et al

in Proceedings of the 2005 International Forum on Aeroelasticity and Structural Dynamics (2005, June)

Flight flutter testing is always carried out under the assumption that aircraft are linear. Recently, this assumption has started to come under question, especially as far as military aircraft are ... [more ▼]

Flight flutter testing is always carried out under the assumption that aircraft are linear. Recently, this assumption has started to come under question, especially as far as military aircraft are concerned. This paper deals with possible methodologies for flight flutter testing of aircraft that are no longer assumed linear. Simulated flight testing is performed for a simple non-linear aeroelastic system with cubic stiffness. The flutter speeds predicted using some of the classical linear flutter prediction methods as well as a non-linear method are compared. It is shown that, for non-linear system undergoing Hopf Bifurcations, classical linear flutter prediction can predict the flutter envelope with reasonable accuracy. However, fully non-linear system identification and stability analysis can not only predict the flutter point but also determine whether it is a linear or non-linear flutter point (i.e. whether divergent or Limit Cycle Oscillations will ensue). Additionally, the non-linear method can predict the amplitudes of LCOs that will occur post-critically. The application of the nonlinear method was successful for noise free data, but the problem of noise corruption still needs further investigation. [less ▲]

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See detailFast contingency filtering based on linear voltage drop estimates
Otomega, Bogdan; Van Cutsem, Thierry ULg

in Proc. IEEE PowerTech Conference (2005, June)

This paper deals with the filtering of harmless contingencies in voltage stability and security analyses. In many systems, a post-contingency load flow allows to identify the contingencies with severe ... [more ▼]

This paper deals with the filtering of harmless contingencies in voltage stability and security analyses. In many systems, a post-contingency load flow allows to identify the contingencies with severe impact on voltage stability, as causing either divergence or large voltage drops. However, for filtering purposes, accurate voltage drops need not be computed; linear estimates obtained from sensitivity formulas are appropriate. For a given contingency, the method used in this paper solves a sparse linear system to update the phase angles, assuming constant voltage magnitudes. Then, assuming constant active power flows in the branches, a second sparse system is solved to update the voltage magnitudes. This yields better accuracy than one full load flow iteration while retaining the sparse structure of a decoupled formulation. For contingency analysis, the incidents are filtered by comparing the voltage drops to a threshold. For secure power margin computations, the same procedure is used after stressing the system in the specified direction. The method has been tested on a real system where it has been found to combine simplicity of implementation, quality of filtering and computational efficiency. [less ▲]

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See detailApplication of a novel oscillatory flow screening micro-reactor to a biotransformation in a two-phase medium
Vicente, A.; Reis, N.; Nobre, C. et al

in Biochemical engineering : frontiers and advances in biotechnology, biological and biomolecular engineering : abstracts”. [S.n. : s.l.] (2005, June)

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See detailThe Critical Neighbourhood Range for Asymptotic Overlay Connectivity in Dense Ad Hoc Networks
Calomme, Sandrine; Leduc, Guy ULg

in Challenges in Ad Hoc Networking (2005, June)

We define, for an overlay built on top of an ad hoc network, a simple criterion for neighbourhood: two overlay nodes are neighbours if and only if there exists a path between them of at most R hops, and R ... [more ▼]

We define, for an overlay built on top of an ad hoc network, a simple criterion for neighbourhood: two overlay nodes are neighbours if and only if there exists a path between them of at most R hops, and R is called the (overlay) neighbourhood range. A small R may result in a disconnected overlay, while an unnecessarily large R would generate extra control traffic. We are interested in the minimum R ensuring overlay connectivity, the so-called critical R. We derive a necessary and sufficient condition on R to achieve asymptotic connectivity of the overlay almost surely, i.e. connectivity with probability 1 when the number of overlay nodes tends to infinity, under the hypothesis that the underlying ad hoc network is itself asymptotically almost surely connected. This condition, though asymptotic, sheds some light on the relation linking the critical R to the number of nodes n, the normalized radio transmission range r and the overlay density D (i.e., the proportion of overlay nodes). This condition can be considered as an approximation when the number of nodes is large enough. Since r is considered as a function of n, we are able to study the impact of topology control mechanisms, by showing how the shape of this function impacts the critical R. [less ▲]

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See detailAn interior point method based optimal power flow
Capitanescu, Florin ULg; Glavic, Mevludin; Wehenkel, Louis ULg

(2005, June)

This paper deals with the solution of an optimal power flow (OPF) problem by the interior point method (IPM). The latter is a very appealing approach to this nonlinear programming problem due to its speed ... [more ▼]

This paper deals with the solution of an optimal power flow (OPF) problem by the interior point method (IPM). The latter is a very appealing approach to this nonlinear programming problem due to its speed of convergence and ease of handling inequality constraints. Two interior point algorithms are presented and compared: the pure primal-dual and the predictor-corrector. Several implementation aspects of these IPM algorithms are also discussed. The OPF is formulated in rectangular coordinates which confers some significant advantages because generally its objective and constraints are quadratic functions. Among the large variety of OPF objectives, emphasis is put on two classical ones: the minimization of generation cost and the minimization of transmission active power losses. The solution obtained by both algorithms proves to be robust for the two OPF sub-problems (optimization of active power flows and reactive power flows) as well as for a full OPF applied to the former objective, which is unanimously recognized as the hardest problem to solve. Finally, numerical results on three test systems ranging from 60 to 300 buses are provided. [less ▲]

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See detailA CIDR Prefix Stopping Rule for Topology Discovery
Donnet, Benoît ULg; Friedman, Timur

in Proc. Algotel (2005, May)

Recently, a first step towards a highly distributed IP-level topology discovery tool has been made with the introduction of the Doubletree algorithm. Doubletree is an efficient cooperative algorithm that ... [more ▼]

Recently, a first step towards a highly distributed IP-level topology discovery tool has been made with the introduction of the Doubletree algorithm. Doubletree is an efficient cooperative algorithm that allows the discovery of a large portion of nodes and links in the network while strongly reducing probing redundancy on nodes and destinations as well as the amount of probes sent. In this paper, we propose to reduce more strongly the load on destinations and, more essentially, the communication cost required for the cooperation by introducing a probing stop rule based on CIDR address prefixes. [less ▲]

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See detailOptimization of mechatronic systems: application to a modern car equipped with a semi-active suspension
Duysinx, Pierre ULg; Bruls, Olivier ULg; collard, Jean-François et al

in Herskowitz, José (Ed.) Proceedings of the 6th World Congress of Structural and Multidisciplinary Optimization (WCSMO6) (2005, May)

The research aims at developing a global mechatronic approach to model, simulate and optimize complex industrial applications. The approach is illustrated with the simulation and the optimization of a ... [more ▼]

The research aims at developing a global mechatronic approach to model, simulate and optimize complex industrial applications. The approach is illustrated with the simulation and the optimization of a modern car (an Audi A6) equipped with a controlled semi-active suspension. An optimization procedure is used to find the best sub-system parameters in order to improve the comfort of the passengers while preserving the car ride and handling performances. Two different modeling and optimization approaches are used and compared. The first one is realized in the MATLAB-SIMULINK environment and is based on a symbolic multibody model of the chassis while the hydraulic actuators, and the controller are integrated using S-functions. Optimization is also carried out in MATLAB using algorithms available in MATLAB libraries, especially a genetic algorithm (GA). On the other hand, the second approach relies on a multibody model based on the Finite Element method whereas the optimization can be realized with an industrial open optimization tool. [less ▲]

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See detailHigher order sigma-delta modulators interfaces for capapcitive sensors
Kraft, Michaël ULg; Dong, Yufeng

in 2005 NSTI Nanotechnology Conference and Trade Show : NSTI Nanotech 2005 (2005, May)

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See detailGeneralized Shape optimization based on the Level Set method
Van Miegroet, Laurent ULg; Moës, Nicolas; Fleury, Claude ULg et al

in Herskowitz, José (Ed.) Proceedings of the 6th World Congress of Structural and Multidisciplinary Optimization (WCSMO6) (2005, May)

This paper describes a first step work devoted to applying XFEM and Level Sets methods in optimization of structures. This first step work is based on integrating an existing XFEM code within a general ... [more ▼]

This paper describes a first step work devoted to applying XFEM and Level Sets methods in optimization of structures. This first step work is based on integrating an existing XFEM code within a general open optimization tool, SAMCEF BOSS QUATTRO. Unlike most of the existing works, this approach is more shape optimization oriented. A library of pre-formatted basic geometric entities (such as ellipses, squares, triangles, etc.) described by Level Sets functions are used. These basic Level Set features can be combined to represent many kinds of interfaces and holes. The construction parameters of the basic Level Sets are considered as the design variables. In order to evaluate the sensitivities, a finite difference scheme over the design variables is used in this first work. Different mechanical responses (energy, weight, displacement, . . .) can be considered as objective functions or constraints in the problem formulation. Several academic 2D test cases of shape and topology optimization are presented within the XFEM and Level Set approach. In addition, a work by Missoum et al. [11], in which the shape and topology optimization of the structure is carried out by an optimal selection of holes characteristics with a genetic algorithm is presented. [less ▲]

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See detailLe tunnel TGV de Soumagne (Belgique) et ses difficultés géologiques
Janssens, B.; Bouhenni; Dethy, B. et al

in Colloque Géoline (2005, May)

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See detailEffect of back mixing during convective drying of wastewater sludges
Léonard, Angélique ULg; Meneses, Eustedio; Salmon, Thierry ULg et al

in Proceeedings of the joint of AFSIA (Association Française de Séchage dans l'Industrie et l'Agriculture) and Working group on Drying of EFCE at INA P-G, Paris, 12th and 13th May, 2005 (2005, May)

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See detailOptimization of Surface Allocation using Heuristic Approaches
Langer, Yves; Bay, Maud ULg; Crama, Yves ULg et al

in COMPIT 2005 , Hambourg, Germany (2005, May)

In this paper, we present a scheduling problem that arises in factories producing large building blocks (in our case, a shipyard workshop producing prefabricated keel elements). The factory is divided in ... [more ▼]

In this paper, we present a scheduling problem that arises in factories producing large building blocks (in our case, a shipyard workshop producing prefabricated keel elements). The factory is divided in several equal size areas. The blocks produced in the factory are very large, and, once a building block is placed in the factory, it cannot be moved until all processes on the building block are finished. The blocks cannot overlap. The objective is to maximize the number of building blocks produced in the factory during a certain time window. To solve this problem, we propose heuristics inspired by techniques initially developed for the three-dimensional bin packing problem, e.g. Faroe and al. (2003), since constraints for both problems are quite similar. Starting from an unfeasible solution, where blocks can overlap, a Guided Local Search (GLS) heuristic is used to minimize the sum of total overlap. If a solution with zero overlap is found, then it is a feasible solution; otherwise the block with the biggest overlap is removed and the procedure is restarted. The GLS algorithm has been improved by Fast Local Search (FST) tech- niques in order to speed up convergence to a local minimum. Additionally, neighborhoods are restricted to their smallest size so as to allow their evaluation in polynomial-time. In a last step, we explain the additional real-life issues arising in the industrial application and how firm-specific constraints can be conveniently considered by the model. [less ▲]

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See detailModelling, Simulation and Optimization of a Shipbuilding Workshop
Bair, Frédéric ULg; Langer, Yves; Caprace, Jean-David ULg et al

in COMPIT'2005 -Conference on Computer Applications and Information Technology in the Maritime Industries, Hamburg (2005, May)

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See detailCaracterization del jambon belga de las ardenas.
Hannecart, François; Deroanne, Claude; Sindic, Marianne ULg

in Abstracts du 3ème Congrès mondial du jambon sec (2005, May)

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See detailIntegration of vehicle, propulsion system and separation unit designs for a launcher using in-flight oxygen collection
Bizzarri, Didier; Hendrick, Patrick; Heyen, Georges ULg et al

in AIAA/CIRA 13th International Space Planes and Hypersonics Systems and Technologies Conference (2005, May)

The use of in-flight Oxygen Collection has shown to significantly improve space launcher performance. The conceptual approach followed by the Royal Military Academy of Brussels (RMA) has tried to widen ... [more ▼]

The use of in-flight Oxygen Collection has shown to significantly improve space launcher performance. The conceptual approach followed by the Royal Military Academy of Brussels (RMA) has tried to widen the available design margins in order to reduce the required technological leap and limit the economical risk associated with such a development. The aim of the ESA-funded theoretical and experimental study on an air separation device is to demonstrate the possibility of performing efficient air distillation in a compact rotating column. An integration of the vehicle, propulsion system and separation unit designs is presented aiming to optimise the overall vehicle performance while keeping technological difficulty and system complexity at a reasonable level. Reference vehicles are presented in their specific mission profiles with an emphasis on TSTO’s. Different layouts of the internal energy and mass flowsheets are compared, in order to make best use of the refrigeration capacity of the hydrogen fuel running though the propulsion system during the first phase of the flight considering the separator as a classical distillation column. This analysis provides the requirements in terms of heat exchange capacity, compression ratios and number of so-called transfer units needed in the separator. Here, the system is intentionally kept simple, to limit complexity, but the analysis is thorough and accurate, including, for example, the effect of the presence of argon. An analysis of the separation unit to reach those requirements is proposed. That includes internals, practical building with estimates of pressure drop, separation performance and flow limitation. Analysis of size reduction of the distillation unit from usual 1-g column to the high-g unit is provided as well as the scale up methodology of laboratory results. First experimental results obtained with our centrifugally enhanced distillation separation system are presented and perspectives for a larger on-board operational unit proposed. [less ▲]

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See detailExperimental Study Of An In-Flight Air Separation Device
Bizzarri, Didier; Hendrick, Patrick; Heyen, Georges ULg et al

in AIAA/CIRA 13th International Space Planes and Hypersonics Systems and Technologies Conference (2005, May)

Intending to provide in-flight Oxygen Collection capability to new launchers, a subscale model of a centrifugally enhanced air distillation unit is under development. The vehicle we foresee for this ... [more ▼]

Intending to provide in-flight Oxygen Collection capability to new launchers, a subscale model of a centrifugally enhanced air distillation unit is under development. The vehicle we foresee for this application is described elsewhere, the present paper concentrating only on the technological and experimental aspects. While the test setup has already been shown to be able to provide the adequate cooling power, the rig is still under construction. The experimental and technical aspects include choices and main trade-offs that had to be made during the design process. Of particular interest are the stainless steel all welded heat exchangers allowing for deep cooling and liquefaction of air from the main compressor and dryers. Specifically, developed hardware is described in details. On the test rig side, design of the rotating cryogenic separator is explained, including mechanical aspects, heat management and sealing. The whole system has modes of operation allowing, among other parameters, to explore various air compositions and mass flows rates on the gaseous and liquid sides. Perspectives are given for the testing of the separator. [less ▲]

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See detailProduction of resorcinol formaldehyde xerogels by convective drying
Léonard, Angélique ULg; Jomaa, Wahbi; Crine, Michel ULg

in Proceedings of the joint conference of AFSIA (Association Française pour le Séchage dans l’Industrie et l’Agriculture) and Working group on Drying of EFCE at INA P-G, Paris, 12th and 13th May, 2005 (2005, May)

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See detailTypical and atypical myopathies of horses
Votion, Dominique ULg

in 2ème Congrès de biologie clinique (2005, April 24)

Une fonction musculaire efficiente repose sur l’intégrité fonctionnelle des systèmes nerveux et musculaire. Les myopathies peuvent résulter d’atteintes nerveuses (myopathies neurogéniques) ou musculaires ... [more ▼]

Une fonction musculaire efficiente repose sur l’intégrité fonctionnelle des systèmes nerveux et musculaire. Les myopathies peuvent résulter d’atteintes nerveuses (myopathies neurogéniques) ou musculaires (myopathies myogéniques). La classification des myopathies selon leur origine n’est pas aisée car, quel que soit le processus pathologique initial, les signes cliniques et les lésions histologiques sont souvent aspécifiques. Dans cet écrit, les principales myopathies équines sont classées selon le tableau clinique. Ainsi, les subdivisions de ce classement incluent le diagnostic différentiel des principales atteintes neuromusculaires. Un type de myopathie pouvant avoir différents tableaux cliniques, il peut se retrouver plusieurs fois dans le tableau. Le détail des principales myopathies équines est précédé de la description des outils dont dispose le vétérinaire afin de poser le diagnostic de myopathie voire de spécifier le type de myopathie dont souffre le cheval. [less ▲]

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See detailCriterion-related validity of the revised Belgian Nursing Minimium Data Set (B-NMDS) throught the actual B-NMDS
THONON, Olivier ULg; VAN BOVEN, Caroline ULg; CODOGNOTTO, Jean ULg et al

in OUD, Nico; SERMEUS, Walter; EHNFORS, Margareta (Eds.) Proceedings of the fifth biennial European Conference of the Association for Common European Nursing Diagnoses, Interventions and Outcomes (2005, April)

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See detailNumerical Simulation of Cold Roll Forming Process
Bui, Quoc Viet; Papeleux, Luc ULg; Boman, Romain ULg et al

in Banabic, Dorel (Ed.) Proceedings of the 8th ESAFORM Conference on Material Forming (2005, April)

Cold roll-forming process of a U profile is modelled and simulated. The simulation is based on a 3D finite element analysis with the help of the home made Metafor code. The prediction on dimensions and ... [more ▼]

Cold roll-forming process of a U profile is modelled and simulated. The simulation is based on a 3D finite element analysis with the help of the home made Metafor code. The prediction on dimensions and deformed shape of the cold roll-formed sheet is in good agreement with the experimental results. Parametric study on roll forming parameters, such as the yield limit and the hardening property of materials, and the distance between stations is performed. [less ▲]

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See detailChromosome aberrations and equine fertility.
Durkin, Keith ULg; Raudsepp, T; Chowdhary, B.P.

in Proceedings of the 32nd Annual Meeting of the Texas Genetics Society (2005, April)

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See detailAnalysis of isokinetic parameters in the development of anterior knee pain syndrome: a prospective study in a military setting
Van Tiggelen, D.; Witvrouw, E.; Coorevits, P. et al

in Abstract Book of the XIV International Congress on Sports Rehabilitation and Traumatology: «The Accelerated Rehabilitation of the Injured Athlete» (2005, April)

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See detailA nation-wide project for the revision of the Belgian Nursing Minimum Data Set : from concept to implementation
SERMEUS, Walter; VAN DEN HEEDE, Koen; MICHIELS, Dominik et al

in OUD, Nico; SERMEUS, Walter; EHNFORS, Margareta (Eds.) Proceedings of the fifth biennial European Conference of the Association for Common European Nursing Diagnoses, Interventions and Outcomes (2005, April)

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See detaila comparison of control strategies applied to an existing ice-storage system
Lemort, Vincent ULg

(2005, April)

While ice storage systems are designed according to a defined strategy for warm day loads, it is interesting to consider other conventional control strategies for mid-season day loads. These different ... [more ▼]

While ice storage systems are designed according to a defined strategy for warm day loads, it is interesting to consider other conventional control strategies for mid-season day loads. These different control strategies, applied to an existing cooling plant, are compared in terms of operating costs and energy consumption. A simplified cooling plant model is built. The chillers, cooling towers, and the ice storage system are modeled as different systems connected together. A time stage equal to 15 minutes is considered to simulate the different control strategies. Existing technical constraints and set points are met. The operating costs of the cooling plant are evaluated by taking into account both the energy and the demand cost rate. In off-design conditions, savings of operating costs are made only if the storage tanks are fully discharged after being fully charged. In this case, ice storage systems reduce the operating costs of the cooling plant by shifting a significant fraction of on-peak energy consumption to off-peak periods and by reducing the on-peak demand. But at the same time, the introduction of an ice storage system in a cooling plant causes the electrical energy consumption to rise because the thermal efficiency of the chillers is reduced when working in ice formation mode. [less ▲]

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See detailThe electronic nose as a warning device of the odour emergence in a compost hall
Nicolas, Jacques ULg; Romain, Anne-Claude ULg; Ledent, C.

in Marco, S.; Montoliu, I. (Eds.) Proceedings of the 11th International Symposium on olfaction and electronic nose (ISOEN 2005) (2005, April)

A self-made electronic nose consisting in a sensor array of six commercial tin oxide gas sensors is used to monitor the odour emission from a compost facility. Supervised data processing tools, such as ... [more ▼]

A self-made electronic nose consisting in a sensor array of six commercial tin oxide gas sensors is used to monitor the odour emission from a compost facility. Supervised data processing tools, such as discriminant analysis, are able to recognize, in real time, the odour of compost with respect to other possible sources in the hall. The paper shows that with unsupervised methods, such as principal component analysis, it is not essential to identify all the possible odour sources during the learning phase. The closeness to the compost group centroid could be used as an indicator of the compost odour level. Alternatively, by a suitable calibration from olfactory measurements, the signals generated by the sensor array can be used to estimate the odour emission rate from the compost hall. Such real time monitoring should allow to assess and to anticipate the annoyance in the surrounding. [less ▲]

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See detailArray of microsystem for live monitoring of high voltage power lines
Renson, Luc ULg; Jamar, Claude ULg; Guérard, Suzanne ULg et al

in Proceedings of the 1st IOMAC (2005, April)

How to use microsystems placed on power lines environment.

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See detailMobility prediction's influence on QoS in wireless networks: a study on a call admission algorithm
François, Jean-Marc; Leduc, Guy ULg

(2005, April)

Several mechanisms increase the QoS level of mobile networks thanks to an underlying mobility prediction method (i.e. a means to predict a mobile's next access router). This paper aims at studying how the ... [more ▼]

Several mechanisms increase the QoS level of mobile networks thanks to an underlying mobility prediction method (i.e. a means to predict a mobile's next access router). This paper aims at studying how the accuracy of the prediction method can influence the network QoS in the particular context of call admission control. It shows that (a) the mobiles behaviour must be adapted according to the prediction scheme accuracy in order to achieve good performance and (b) the admission algorithm can be modified to increase its fairness and to give mobiles an incentive to do such an adaptation. [less ▲]

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See detailHétérogénéité, mon cher souci
Lafontaine, Dominique ULg

(2005, April)

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See detailInfluence of the nozzle capacity on the performance of a domestic fuel oil boiler
Ngendakumana, Philippe ULg; Masy, Cédric

in 2nd Edition of European Combustion Meeting (ECM 2005) (2005, April)

In order to investigate the influence of the nozzle capacity on the performance of fuel oil boilers, tests have been performed in transient and steady state regimes on our experimental boiler. The aim of ... [more ▼]

In order to investigate the influence of the nozzle capacity on the performance of fuel oil boilers, tests have been performed in transient and steady state regimes on our experimental boiler. The aim of the tests was to deduce the better couple nozzle - fuel injection pressure to reach the desired output power while producing fewer pollutants as possible. In short, a high fuel injection pressure associated with a low capacity nozzle is recommended. [less ▲]

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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 ▲]

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See detailStability and LCO Amplitude Prediction for Aeroelastic Systems with Aerodynamic and Structural Nonlinearities Using Numerical Continuation
Vio, Gareth Arthur; Dimitriadis, Grigorios ULg; Cooper, Jonathan Edward

in RTO-MP-AVT-123 Flow-Induced Unsteady Loads and the Impact on Military Applications (2005, April)

This paper deals with the prediction of stability boundaries and Limit Cycle Oscillation amplitudes for aeroelastic systems with nonlinear unsteady aerodynamic loads and/or nonlinearity in the structure ... [more ▼]

This paper deals with the prediction of stability boundaries and Limit Cycle Oscillation amplitudes for aeroelastic systems with nonlinear unsteady aerodynamic loads and/or nonlinearity in the structure. The Numerical Continuation method is used to accurately predict bifurcation conditions and LCO amplitudes for aeroelastic systems with various types of nonlinearity without the need for extensive CFD calculations. It is shown that it is possible to completely characterise the stability of systems undergoing subcritical and supercritical bifurcations. The method is applied to a pitch-plunge airfoil subjected to transonic aerodynamics and freeplay structural nonlinearity. The results from this analysis are compared to those obtained from full numerical simulation to ensure their accuracy. [less ▲]

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See detailEffect of a bovine colostrum supplementation in piglet diet at weaning on growth performances, food ingestion and faecal E. coli concentrations.
Boudry, Christelle ULg; Didderen, Isabelle; Wavreille, José et al

in Proceedings of the British Society of Animal Science (2005, April)

Bovine colostrum supplementation in piglets diet stimulates food intake and reduces the faecal E. coli population during the first week after weaning, inducing a liveweight gain increase. A reduction of ... [more ▼]

Bovine colostrum supplementation in piglets diet stimulates food intake and reduces the faecal E. coli population during the first week after weaning, inducing a liveweight gain increase. A reduction of the food conversion ratio was also observed, suggesting a better nutrient assimilation by the piglets. [less ▲]

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See detailA comparative study of isokinetic training using two brands of dynamometers
Croisier, Jean-Louis ULg; Herve, M. N.; Forthomme, Bénédicte ULg

in Abstract Book of the XIV International Congress on Sports Rehabilitation and Traumatology: «The Accelerated Rehabilitation of the Injured Athlete» (2005, April)

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See detailImproved Algorithms for Network Topology Discovery
Donnet, Benoît ULg; Friedman, Timur; Crovella, Mark

in International Workshop on Passive and Active Network Measurement (2005, April)

Topology discovery systems are starting to be introduced in the form of easily and widely deployed software. However, little consideration has been given as to how to perform large-scale topology ... [more ▼]

Topology discovery systems are starting to be introduced in the form of easily and widely deployed software. However, little consideration has been given as to how to perform large-scale topology discovery efficiently and in a network-friendly manner. In prior work, we have described how large numbers of traceroute monitors can coordinate their efforts to map the network while reducing their impact on routers and end-systems. The key is for them to share information regarding the paths they have explored. However, such sharing introduces considerable communication overhead. Here, we show how to improve the communication scaling properties through the use of Bloom filters to encode a probing stop set. Also, any system in which every monitor traces routes towards every destination has inherent scaling problems. We propose capping the number of monitors per destination, and dividing the monitors into clusters, each cluster focusing on a different destination list. [less ▲]

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See detailEffect of ruminal degradable nitrogen deficit on nitrogen metabolism in growing double-muscled Belgian Blue bulls fed maize silage based diet.
Valkeners, Damien; Beckers, Yves ULg; Van Laere, Marc et al

in Proceedings of the British Society of Animal Science annual conference2005, York, UK. 4th-6th April, 2005 (2005, April)

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See detailEffect of various levels of imbalance between energy and nitrogen supplies in the rumen on nitrogen metabolism in growing double-muscled Belgian Blue bulls fed maize silage based diet.
Valkeners, Damien; Beckers, Yves ULg; Amant, Stéphanie et al

in Proceedings of the British Society of Animal Science annual conference2005, York, UK. 4th-6th April, 2005 (2005, April)

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See detailPhotospheric abundance peculiarities in chromospherically active stars
Morel, Thierry ULg; Micela, G.; Favata, F.

in 13th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun (2005, March 01)

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See detailAdult Controversy : Long-term monitoring of acromegaly
Beckers, Albert ULg

in 37th International symposium - GH and Growth Factors in Endocrinology and Metabolism (2005, March)

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See detailA Throughflow Analysis Tool Based on the Navier-Stokes Equations
Simon, Jean-Francois; Léonard, Olivier ULg

in 6th European Conference on Turbomachinery Fluid Dynamics and Thermodynamics - Conference Proceedings (2005, March)

This paper describes a throughlow analysis tool based on a modern ¯nite-volume approach. The numerical model is obtained by averaging the 3-D Navier-Stokes equations in the blade passage, keeping only the ... [more ▼]

This paper describes a throughlow analysis tool based on a modern ¯nite-volume approach. The numerical model is obtained by averaging the 3-D Navier-Stokes equations in the blade passage, keeping only the axisymmetric part of the equations. The averaging reduces the spatial dimension of the problem but introduces additional terms, the blade forces, which have to be modeled. In the present viscous through°ow model, the 2-D annulus endwall °ow is captured by the resolution of the Navier-Stokes equations coupled to a simple mixing-length turbulence model. This allows to simulate high energy interactions and high losses near the endwalls. However, 3-D features such as tip or corner °ows cannot be predicted in axisymmetric computations. In the present contribution, these 3-D e®ects are modeled using empirical correlations from the literature. They are introduced into the equations, together with the pro¯le losses, by the so-called distributed loss model. Two test-cases, a high subsonic single stage compressor and a low speed three stage compressor, show the potential of the method. [less ▲]

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See detailArchitecture d'une boîte à outils d'algorithmes d'ingénierie de trafic et application au réseau GEANT
Skivée, Fabian; Balon, Simon ULg; Delcourt, Olivier et al

in Ingénierie des protocoles - Qualité de service, multimédia et mobilité (2005, March)

This paper presents the software architecture of a traffic engineering toolbox. The methods already included cover MPLS-based intra-domain traffic engineering (TE), but will soon cover IP-based TE and ... [more ▼]

This paper presents the software architecture of a traffic engineering toolbox. The methods already included cover MPLS-based intra-domain traffic engineering (TE), but will soon cover IP-based TE and inter-domain TE. This toolbox provides an open source software that allows an operator to test methods coming from the academic research. A researcher can also use the toolbox for comparing and promoting his/her TE algorithms. The toolbox is designed to be deployed as an on-line tool in a operational network or as a traffic engineering simulator. We present a case study of traffic optimisation on the GÉANT network that compares different routing algorithms, evaluates different protection cost, and analyses the worst-case link failure. [less ▲]

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See detailFongicides: Protection contre la septoriose en froment: quelle stratégie vis-à-vis de la résistance aux strobilurines?
Moreau, Jean-Marc; Bodson, Bernard ULg; Vancutsem, Françoise ULg

in Fumure et protection phytosanitaire des céréales (2005, February 23)

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See detailFongicides: la septeoriose est résistante aux strobilurines
Moreau, Jean-Marc; Bodson, Bernard ULg; Vancutsem, Françoise ULg

(2005, February 23)

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See detailVariétés, phytotechnie et rendement en paille du froment d'hiver
Vancutsem, Françoise ULg; Bodson, Bernard ULg; Minsier, François et al

in Fumure et protection phytosanitaire des céréales (2005, February 23)

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See detailL'azote minéral du sol; sous froment d'hiver: Situation au 10 février 2005
Destain, Jean-Pierre ULg; Couvreur, Luc; Herman, Jean-Luc et al

in Fumure et protection phytosanitaire des céréales (2005, February 23)

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See detailFongicides: Schéma de protection fongicide et sensibilité variétale
Vancutsem, Françoise ULg; Bodson, Bernard ULg; Moreau, Jean-Marc

in Fumure et protection phytosanitaire des céréales (2005, February 23)

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See detailLes conseils de fumure azotée
Bodson, Bernard ULg; Destain, Jean-Pierre ULg; Vancutsem, Françoise ULg et al

in Fumure et protection phytosanitaire des céréales (2005, February 23)

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See detailActualités dans le domaine de la fumure azotée
Bodson, Bernard ULg; Vancutsem, Françoise ULg; Destain, Jean-Pierre ULg et al

in Fumure et protection phytosanitaire des céréales (2005, February 23)

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See detailEffet du colostrum bovin administré à des porcelets au sevrage sur la morphologie de la paroi intestinale et sur le système immunitaire
Boudry, Christelle ULg; Dalle, Marie-Julie; Halleux, Caroline et al

in 37èmes journées de la recherche porcine (2005, February)

Two groups (A and B) of 6 piglets, weaned at 21 days (D0), received ad libitum the same diet during three weeks. The piglets of group A were not submitted to a colostrum supplementation while those of the ... [more ▼]

Two groups (A and B) of 6 piglets, weaned at 21 days (D0), received ad libitum the same diet during three weeks. The piglets of group A were not submitted to a colostrum supplementation while those of the group B received daily and orally 5 g of bovine colostrum. Each week, piglets were weighed and blood was taken on each one of them. One piglet of each group was sacrified on D0 and the rest of the animals on D21. Mesenteric lymph nodes (ML), iléal Peyer patches (iPP), jejunum and spleen biopsies were taken on each piglet before death. The haematological values and the intestinal histo-morphological data between the two groups were not significantly different, but FACS analyses on the lymphocytes in the biopsies and the determination of stimulation index suggested a significative effect of colostrum on the lymphocytes populations, with, in the ML, an increase of the LB population (14 % vs 28 %, P < 0,05) and, in the iPP, a reduction of the LB's (54,99 % vs 8,44 %, P < 0,01) with an increase of the LT cells (16,87 % vs 72,00 %, P < 0,001). An increase of the lymphocyte stimulation index from piglets receiving colostrum was observed the second day of in vitro stimulation with colostrum. In brief, the answer of the immunity system to bovine colostrum seems to be restricted to the intestinal immunity system and is characterised by an activation, a multiplication and a modification of the lymphocytes ratios. [less ▲]

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See detailAutomatic Scoring of sleep apnea and hypopnea by analysis of mandibular movements
Senny, Frédéric ULg; Destiné, Jacques ULg; Verly, Jacques ULg et al

in M.H.Hamza (Ed.) Proceedings of the 3rd International IASTED International conference on Biomedical Engineering (2005, February)

In this paper, we propose a method for sleep apnea and hypopnea detection by analyzing the mandibular movements recorded during sleep. This signal, highly correlated with the esophageal pressure during ... [more ▼]

In this paper, we propose a method for sleep apnea and hypopnea detection by analyzing the mandibular movements recorded during sleep. This signal, highly correlated with the esophageal pressure during apnea or hypopnea, is a good marker of respiratory efforts. The respiratory efforts and their background activity are used to detect salient mandibular movements related to sleep apnea and hypopnea, to delineate and to recognize episodes of sleep apnea and hypopnea. The method presented may be extended to others breathing disorders such as Respiratory Efforts Related Arousals (RERA). [less ▲]

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See detailLe déséquilibre de force musculaire favorise-t-il la survenue d’une lésion ?
Croisier, Jean-Louis ULg

in Actes du 2ème Colloque Médico-sportif « Entre laboratoire et terrain » (Liège) (2005, February)

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See detailLa diversification en productions animales
Wavreille, José; Rondia, Pierre; Decruyenaere, Virginie et al

in CRA-W; FUSAGx (Eds.) 10ème Carrefour des Productions animales : L’élevage : hier, aujourd’hui, demain quelles attentes pour quels enjeux ? (2005, January 26)

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See detailDifférenciation et fonctionnalité des produits agricoles
Rondia, Pierre; Dehareng, Frédérick; Beckers, Yves ULg et al

in CRA-W; FUSAGx (Eds.) 10ème Carrefour des Productions animales : L’élevage : hier, aujourd’hui, demain quelles attentes pour quels enjeux ? (2005, January 26)

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See detailAlimentation azotée du taurillon Blanc Bleu Belge culard: état des connaissances, nouvelles avancées et perspectives.
Valkeners, Damien; Beckers, Yves ULg; Froidmont, Eric et al

in CRA-W; FUSGAx (Eds.) 10ème Carrefour des Productions animales. L’élevage : hier, aujourd’hui, demain quelles attentes pour quels enjeux ? (2005, January 26)

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See detailAppréhender le caractère durable des systèmes agraires
Stilmant, Didier ULg; Jamar, Daniel; Debouche, Charles ULg et al

in Proceeding des dixième carrefour des productions animales (2005, January 26)

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See detailQuasars with Gaia: Identification and Astrophysical Parameters
Claeskens, Jean-François ULg; Smette, A.; Surdej, Jean ULg

in Turon, C.; O'Flaherty, K. S.; Perryman, M. A. C. (Eds.) Proceedings of the Gaia Symposium "The Three-Dimensional Universe with Gaia" (ESA SP-576) (2005, January 01)

Gaia will provide astrometric and photometric observations for about 500 000 quasars distributed over the whole sky. The latter would constitute an isotropic grid of fixed sources perfectly suited to ... [more ▼]

Gaia will provide astrometric and photometric observations for about 500 000 quasars distributed over the whole sky. The latter would constitute an isotropic grid of fixed sources perfectly suited to determine the referential frame. However, they must first be properly identified among stars, whose population is about 2000 times larger. Using broad and medium band photometry, we first compare the efficiency of two analysis methods (Ï 2 fitting and Artificial Neural Networks, ANNs) to produce the QSO catalogue with the lowest amount of contamination by stars. We then investigate whether the Gaia photometry could also provide precise values of the QSO astrophysical parameters (APs, like the redshift, the continuum slope, the emission line strength and possibly the extinction). To reach that purpose, we also compare the performances of the Spectral Principal Component Analysis (SPCA) with those of the Ï 2 fitting and ANN analysis. [less ▲]

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See detailHipparcos Astrometric Binaries in the Ninth Catalogue of Spectroscopic Binary Orbits: A Testbench for the Detection of Astrometric Binaries with Gaia
Jancart, Sylvie ULg; Jorissen, A.; Pourbaix, D.

in O'Flaherty, K.S.; Perryman, M.A.C (Eds.) The Three-Dimensional Universe with Gaia (2005, January 01)

The Ninth Catalogue of Spectroscopic Binary Orbits1 and the Hipparcos Intermediate Astrometric Data (IAD) are used to retrieve astrometric binaries from the Hipparcos data. It is found that basically all ... [more ▼]

The Ninth Catalogue of Spectroscopic Binary Orbits1 and the Hipparcos Intermediate Astrometric Data (IAD) are used to retrieve astrometric binaries from the Hipparcos data. It is found that basically all (non-SB2) systems with periods larger than about 100 d, and parallaxes larger than 5-10 mas exhibit an astrometric orbital motion which can be extracted from the IAD. The lessons learned from this kind of approach will be very valuable for the design of the Gaia reduction pipeline. [less ▲]

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See detailDetection and Characterization of Extra-Solar Planets with Gaia
Lattanzi, M. G.; Casertano, S.; Jancart, Sylvie ULg et al

in O'Flaherty, K.S.; Perryman, M.A.C (Eds.) The Three-Dimensional Universe with Gaia (2005, January 01)

The scope of this paper is twofold. First, it describes the simulation scenario and the results of the large scale double-blind test campaign set-up by the Planetary System Working Group for the realistic ... [more ▼]

The scope of this paper is twofold. First, it describes the simulation scenario and the results of the large scale double-blind test campaign set-up by the Planetary System Working Group for the realistic simulation of the Gaia capabilities in detecting extra-solar planets. Present limitations and envisaged future improvements are also discussed. Then, the identified capabilities are put in context by highlighting the unique contributions that the Gaia exo-planet discoveries will be able to bring to the science of extra-solar systems of the next decade. [less ▲]

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See detailOrbit Determination for Gaia Spectroscopic Binaries
Jancart, Sylvie ULg; Pourbaix, D.

in O'Flaherty, K.S.; Perryman, M.A.C (Eds.) The Three-Dimensional Universe with Gaia (2005, January 01)

Synthetic radial velocities for a population of 2300+ known spectroscopic binaries are generated according to the present scanning law. The effect of the distribution of the observations and of the noise ... [more ▼]

Synthetic radial velocities for a population of 2300+ known spectroscopic binaries are generated according to the present scanning law. The effect of the distribution of the observations and of the noise on the orbit fitting is investigated. According to our preliminary results short periods, below one day, will be hard to identify among the many aliases, even in the absence of noise. Requirements in terms of computing power for this shell task are estimated in conjunction with the adopted algorithm for the period search part of the orbit reconstruction. These results are for binaries detected in the Radial Velocity Spectrometer only. [less ▲]

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See detailEpidemiology of atypical myopathy: descriptive phase
Votion, Dominique ULg; Linden, Annick ULg; Desmecht, Daniel ULg et al

in In Proceeding: First Scientific Symposium of the European College of Equine Internal Medicine (ECEIM) (2005, January)

Atypical myopathy (AM) in grazing horses is a frequently fatal condition that has been reported in several European countries. In Belgium, since autumn 2000, AM was confirmed in 39 equids based on ... [more ▼]

Atypical myopathy (AM) in grazing horses is a frequently fatal condition that has been reported in several European countries. In Belgium, since autumn 2000, AM was confirmed in 39 equids based on characteristic histological lesions in postural and respiratory muscles. This study describes the history, clinical signs and biochemical changes associated with AM in these confirmed cases. [less ▲]

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See detailNon-Linear Identification Using a Genetic Algorithm Approach for Model Selection
Platten, Michael F; Wright, Jan Robert; Worden, Keith et al

in Proceedings of the 23rd International Modal Analysis Conference (2005, January)

The Non-Linear Resonant Decay Method is an approach for the identification of non-linear systems with large numbers of degrees of freedom. The identified non-linear model is expressed in linear modal ... [more ▼]

The Non-Linear Resonant Decay Method is an approach for the identification of non-linear systems with large numbers of degrees of freedom. The identified non-linear model is expressed in linear modal space and comprises the modal model of the underlying linear system with additional terms representing the non-linear behaviour. Potentially, a large number of these non-linear terms will exist but not all of them will be significant. The problem of deciding which and how many terms are required for an accurate identification has previously been addressed using the Forward Selection and Backward Elimination techniques. In this paper, a Genetic Algorithm optimisation is proposed as an alternative to those methods. A simulated 5-DOF lumped parameter non-linear system is used to demonstrate the proposed optimisation. The use of separate data sets for the identification and validation of the modal model is also investigated. It is found that the Genetic Algorithm approach yields significantly better results than the Backward Elimination and Forward Selection algorithms in many cases. [less ▲]

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See detailDevelopment of a general method for the verification of composite beams against lateral torsional buckling in the erection phase
Boissonnade, N.; Cajot, L. G.; Haller, M. et al

in Proceedings of the 2005 Eurosteel Conference on Steel and Composite Structures (2005)

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See detailSpeeding up Feature Selection by Using an Information Theoretic Bound.
Meyer, Patrick ULg; Caelen, Olivier; Bontempi, Gianluca

in BNAIC (2005)

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See detailSartre en de "happening", of de crisis van het beeld
Steinmetz, Rudy ULg

in Sartres verjaardagen. Giften et gaven (2005)

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See detailLogiques de champs et habitus journalistique. L’activation de l’État-providence en Belgique
Geuens, Geoffrey ULg

in Durand, Pascal; Dubois, Jacques; Winkin, Yves (Eds.) Le Symbolique et le Social. La Réception internationale de la pensée de Pierre Bourdieu - Actes du colloque international Le Symbolique et le Social. La Réception internationale de la pensée de Pierre Bourdieu (Centre culturel international de Cerisy-la-Salle, 12-19 juillet 2001) (2005)

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See detailSeismic assessment of an S-shape building with expansion joints
Plumier, André ULg; Denoël, Vincent ULg; Sanchez, Luiz et al

(2005)

An elastic analysis of an existing 20-storey reinforced concrete moment resisting frame divided in 3 blocks shows that beams supported on corbels of the adjacent block at the expansion joint loose their ... [more ▼]

An elastic analysis of an existing 20-storey reinforced concrete moment resisting frame divided in 3 blocks shows that beams supported on corbels of the adjacent block at the expansion joint loose their support when each independent block vibrate on its own under earthquake. Different reconnection hypothesis were considered, ranging from fixing totally each block to the adjacent one to more flexible options leaving some free relative move between blocks. An elastic modal superposition followed by a pushover analysis considering the final reconnection principle were made. The degrees of freedom of the joint reconnections were observed to be an important parameter. The solution found leaves a free relative rotational move between blocks and a flexible translational movement, so that forces at the connection do not become uselessly high. The springs used (long tie rods) work essentially elastically so that no permanent relative displacement exists between blocks after an earthquake. [less ▲]

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See detailAnalysis of tapered steel frames using beam elements and comparison with shell elements
Boissonnade, N.; Degée, Hervé ULg

in Proceedings of the 4th European Conference on Steel Structures (2005)

This paper deals with the consequences of modelling a tapered steel frame with beam elements rather than shell elements. It starts by presenting a specific beam element accounting for the tapering that ... [more ▼]

This paper deals with the consequences of modelling a tapered steel frame with beam elements rather than shell elements. It starts by presenting a specific beam element accounting for the tapering that allows performing geometrically as well as materially non-linear analysis. Then, several kinds of analyses are carried out on two different frames and the results obtained using shell elements, tapered beam elements and prismatic beam elements are compared. This comparison shows that the use of tapered elements leads to results in close agreement with those obtained by shell elements, unlike the prismatic ones. The paper aims at showing that resorting to a so-called segmentation technique should be decided carefully. It also intends at showing the accuracy and convenience of tapered elements when compared to shell models: the total number of degrees of freedom is indeed significantly reduced, leading to easier meshing, shorter computation time and easier interpretation of results. [less ▲]

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See detailHigh order bandpass sigma delta interfaces for vibratory gyroscopes
Kraft, Michael ULg; Dong, Y; Redman-White, W

in Proc. IEE Sensors (2005)

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See detailAnalyse numérique des tests expérimentaux à grande vitesse de déformation
Jeunechamps, Pierre-Paul ULg; Ponthot, Jean-Philippe ULg; BOUVIER, S. et al

in 7ème Colloque National en calcul des Structures (2005)

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See detailLinking biochemical and biophysical variables derived from imaging spectrometers to ecological models - The HyEco'04 Group Shoot.
Kooistra, L; Clevers, J; Schaepman, M et al

in Zagajewski, B; Sobczak, M; Wrzesien, M (Eds.) New Quality in Environmental Studies. Proceedings of 4th EARSeL Workshop on Imaging Spectroscopy (2005)

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See detailA variational formulation of constitutive models and updates in nonlinear finite viscoelasticity
FANCELLO, E.; Stainier, Laurent ULg; Ponthot, Jean-Philippe ULg

in 7ème Colloque National en calcul des Structures (2005)

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See detailStress oxydant et fluidité membranaire du globule rouge du cheval athlète : effets de l’exercice et de la complémentation en antioxydants
Portier, K.; de Moffarts, Brieuc; Lekeux, Pierre ULg et al

in 31ème Journée de la Recherche Equine des Haras Nationaux (2005)

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See detailLa langue comme facteur d'intégration ou d'exclusion. L'Athènes du Ve s. et la Rome de Cicéron
Rochette, Bruno ULg

in Angelli Bertinelli, Maria Gabriella (Ed.) Serta antiqua et mediaevalia VII. Il cittadino, lo straniero, Il barbaro, fra integratione ed emarginazione nell'antichità. Atti del I° Incontro internazionale di Storia Antica (2005)

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See detailReference values for left ventricular echocardiographic parameters during atropine/dobutamine stress testing
Sandersen, Charlotte ULg; Detilleux, Johann ULg; De Moffarts, Brieuc et al

in Proceedings of the 44th Annual Congress of the British Equine Veterinary Association (BEVA) (2005)

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See detailFunction and dysfunction of the lower airways
Lekeux, Pierre ULg; Art, Tatiana ULg

in Proceedings: 9e Congrès de médecine et chirurgie équine (2005)

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See detailSensitivity Analysis of Escherichia coli's Tricarboxilic Acid Cycle under Anaerobic Conditions
Ofiteru, I. R.; Lavric, V.; Allgöwer, F. et al

in Proc. Foundations of Systems Biology in Engineering, FOSBE 2005 (2005)

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See detailLearning, then Compacting Visual Policies
Jodogne, Sébastien ULg; Piater, Justus ULg

in 7th European Workshop on Reinforcement Learning (2005)

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See detailDevelopment of a neural network to predict the final geometry of forged rings after cooling
Casotto, S.; Bruschi, S.; Pascon, Frédéric ULg et al

in Banabic, D. (Ed.) Proceedings of the 8th ESAFORM Conference on Material Forming (Vol. 2) (2005)

The paper deals with an application of Artificial Neural Networks (ANNs) to predict the geometry of hot forged pieces after cooling. Different ANNs have been considered and evaluated; then a network with ... [more ▼]

The paper deals with an application of Artificial Neural Networks (ANNs) to predict the geometry of hot forged pieces after cooling. Different ANNs have been considered and evaluated; then a network with two hidden layers has been set up. Training and testing data have been obtained through calibrated numerical simulations of the cooling phase carried out with a finite element (F.E.) code. The good agreement between predicted and numerical results confirms the possibility of using well-trained neural network to foresee final dimensions of pieces after hot forging operations. [less ▲]

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See detailRobust Non-Rigid Object Tracking Using Point Distribution Models
Mathes, Tom; Piater, Justus ULg

in British Machine Vision Conference (2005)

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See detailDetermination of the optimal forging conditions of a Cr-Mo-V high alloy steel through a microstructural, thermophysical and mechanical study
Bouffioux, Chantal ULg; Carton, Marc ULg; Lecomte-Beckers, Jacqueline ULg et al

in Banabic, D. (Ed.) Proceedings of the 8th ESAFORM Conference on Material Forming (Vol. 1) (2005)

The forging process of cylinders requires the knowledge of material recrystallisation conditions to prevent crack appearance. Due to the continuous recrystallisation during forging, very large ... [more ▼]

The forging process of cylinders requires the knowledge of material recrystallisation conditions to prevent crack appearance. Due to the continuous recrystallisation during forging, very large deformations can be applied as the generated dislocations do not yield to hardening but to recrystallisation phenomenon. This paper summarizes the data identification of a FEM recrystallisation model and defines the optimal forging process for one roll. [less ▲]

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See detailObject Tracking Using Color Interest Points
Gabriel, Pierre; Hayet, Jean-Bernard; Piater, Justus ULg et al

in International Conference on Advanced Video and Signal based Surveillance (2005)

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See detailEndocarditis in horses: a retrospective study of five cases
Amory, Hélène ULg; Bertrand, P; Delguste, Catherine ULg et al

in Proceedings of the 44th Annual Congress of the British Equine Veterinary Association (BEVA) (2005)

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See detailInteractive Learning of Mappings from Visual Percepts to Actions
Jodogne, Sébastien ULg; Piater, Justus ULg

in 22nd International Conference on Machine Learning (2005)

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See detailAccounting for coherence in wind forces in finite element models
Denoël, Vincent ULg

in Proceedings of the Eurodyn 2005 Conference (2005)

The behaviour of civil engineering structures subjected to wind forces is generally approached by means of finite element models. These numerical models are necessary since the shape of the structure as ... [more ▼]

The behaviour of civil engineering structures subjected to wind forces is generally approached by means of finite element models. These numerical models are necessary since the shape of the structure as well as the representation of the applied forces are difficult to handle in closed forms. In stochastic dynamic analyses, the coherence of the applied forces – in this context coming from the wind flow – is represented by the off-diagonal terms in the power spectral density matrix. This matrix is obtained by assembling elementary matrices, each of them corresponding to a stochastically loaded finite element. Even though the unique rigorous approach is not so complicated, simplified formulations are generally used to set up these elementary matrices. These simplifications result in a bad estimation of the high frequency content of the applied forces. Comparing these approached power spectral density’s to the actual ones enables to determine numerical admittance functions which allow correcting the bad estimation of the forces. This paper presents several finite element formulations for the estimation of the applied forces and derives the corresponding expressions of the numerical admittance functions. [less ▲]

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See detailUnsupervised Learning of Visual Feature Hierarchies
Scalzo, Fabien; Piater, Justus ULg

in Proceedings of the International Conference on Machine Learning and Data Mining (MLDM) (2005)

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See detailInterferometric fringes projection system for 3D profilometry and relief investigation
Moreau, Vincent; Laboury, Dimitri ULg; Tilkens, Bernard et al

in Optical Methods for Arts and Archaeology, Proceedings of SPIE, Vol. 5857 (2005)

We present a new 3D full-frame profilometer based on structured laser light projection method. This device takes advantage of the polarization states splitting technique for producing and shifting ... [more ▼]

We present a new 3D full-frame profilometer based on structured laser light projection method. This device takes advantage of the polarization states splitting technique for producing and shifting multiple sinusoidal Young’s interference patterns that are projected on the inspected surface. The principle of the technique is presented and we discuss the advantages of monochromatic light projection method as a mean to overcome ambient lighting for in-situ measurement. Some results that we obtained on objects from the Egyptian Department of the British Museum are presented to demonstrate that 3D laser profilometry is a worthwhile technique for epigraphic investigations where naked-eye inspections fail. [less ▲]

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See detailTracking by cluster analysis of feature points and multiple particle filters
Du, Wei ULg; Piater, Justus ULg

in 3rd International Conference on Advances in Pattern Recognition (2005)

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See detailLarge strain elasto/viscoplastic constitutive model. Theory and numerical scheme
Ponthot, Jean-Philippe ULg; GARCIA-GARINO, C.; MIRASSO, A.

in MECOM 2005, Mecanica Computational (2005)

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See detailTask-Driven Learning of Spatial Combinations of Visual Features
Jodogne, Sébastien ULg; Scalzo, Fabien; Piater, Justus ULg

in Proc. of the IEEE Workshop on Learning in Computer Vision and Pattern Recognition (2005)

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See detailAnalysis of the vegetation trends using low resolution remote sensing data in the Sahel (1982-1999) for the monitoring of desertification
Hountondji, Yvon ULg; Sokpon, Nestor; Ozer, Pierre ULg

in Röder, Achim; Hill, Joachim (Eds.) Abstract Book - Remote Sensing and Geoinformation Processing in the Assessment and Monitorinf of Land Degradation and Desertification (2005)

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See detailApprentissage non-supervisé de hiérarchies de caractéristiques visuelles
Scalzo, Fabien; Piater, Justus ULg

in Actes du Congrès ORASIS (2005)

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See detailLandslide risk analysis in the Mailuu-Suu valley (Kyrgyzstan) by means of remote sensing techniques
Danneels, Gaelle; Pirard, Eric ULg; Torgoev, Isakbek et al

in Geophysical Research Abstracts (2005)

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See detailBeyond deforestation: use of landscape metrics and satellite imagery to analyze tropical forest fragmentation.
Colson, F; Shimabukuro, Y E; Bogaert, Jan ULg

in Proceedings of: Forestsat 2005, workshop on operational tools in forestry using remote sensing techniques. (2005)

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See detailDistance and location processes in memory for time: An update
Bastin, Christine ULg; Friedman, William J.

in Proceedings of the 28th International Congress of Psychology (2005)

Memory for times of past events depends on direct impressions of the temporal “distances” of the events in the past and the reconstruction of temporal “locations. Two studies shed light on the possible ... [more ▼]

Memory for times of past events depends on direct impressions of the temporal “distances” of the events in the past and the reconstruction of temporal “locations. Two studies shed light on the possible neurological basis of location-based processes. In an ERP study, adults performed tasks thought to bias subjects to use distance or location processes. Late frontal activity was specifically linked to location-based processes. In another study using the same tasks, aging was found to disrupt location-based processes more than distance-based processes. Age-related differences in the use of location-based processes were mediated by speed of processing and by working-memory capacities. [less ▲]

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