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See detailSimulation Based Assessment of Heat Pumping Potential in Non-Residential Buildings – Part 1: Modeling
Bertagnolio, Stéphane ULiege; Stabat, Pascal; Soccal, Benjamin et al

in Proceedings of the 10th REHVA World Congress - Clima 2010 (2010, May)

1 Introduction A solution to reduce the energy consumption in office and health care buildings consist in better exploiting the potential of the heat pump technology. This can be done by recovering heat ... [more ▼]

1 Introduction A solution to reduce the energy consumption in office and health care buildings consist in better exploiting the potential of the heat pump technology. This can be done by recovering heat at the condenser when the chiller is used to produce cold (simultaneous heating and cooling demands) or by using the chiller in heat pump mode (non-simultaneous heating and cooling demands). Both strategies appear particularly feasible when cooling and heating needs and the heat pump technology are, at least partly, present in the building, which is often the case in the tertiary sector. The analysis of these reversibility and recovery potentials is one of the subjects of the IEA-ECBCS Annex 48 project. 2 Simulation tools A package of simulation tools is developed in order to assess the energy and environmental performances and costs of such solutions. A first tool allows a quick estimation of the potential of recovery and reversibility options, starting with limited information and using a limited amount of parameters. It consists in simulating the considered building and its secondary HVAC system in order to generate hourly values of heating and cooling system loads and to compute theoretical reversibility and recovery potentials. This first simulation run can be performed by mean of a calibrated building energy simulation tool (Trnsys, Energyplus…). Hourly values of heating and cooling loads of a given building can also be obtained through in-situ measurements. A second tool allows to simulate the behavior of the heat pump plant and to compute its performances using the previously computed heating and cooling load profiles as inputs. The considered heat pump configuration is then compared to a classical HVAC primary system (composed of a boiler and a chiller) in terms of primary energy consumption, CO2 emissions and costs. In this first paper, the development of such models and their implementation in an equation-based solver are described. The considered heat pump configurations are presented and the models of the main components (heat pump, boiler, thermal storage system, cooling tower and ground heat exchanger) are described. Five general configurations are considered: (1) reversible air-to-water heat pump, (2) exhaust air heat pump, (3) dual condenser heat pump, (4) water loop systems and (5) ground coupled heat pump. The modeling hypotheses, the control algorithms and the connection of these models into global heat pump systems simulation models are discussed. Finally, it is shown how simple equation-based simulation models can be connected to allow quick and robust assessment of the potential of complex heat pump systems. [less ▲]

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See detailNotes de recherche n°12. Le remembrement urbain
Marique, Anne-Françoise ULiege; Lejeune, Zoé ULiege; Halleux, Jean-Marie ULiege et al

Report (2010)

Cette note de recherche se penche sur un nouvel outil wallon en faveur de la redynamisation des villes, le remembrement urbain. Cet outil qui trouve son origine dans la Déclaration de la Politique ... [more ▼]

Cette note de recherche se penche sur un nouvel outil wallon en faveur de la redynamisation des villes, le remembrement urbain. Cet outil qui trouve son origine dans la Déclaration de la Politique régionale 2004-2009, n’a été appliqué jusqu’à présent que dans cinq dossiers. L’approche prospective adoptée dans cette note de recherche se base sur ces cinq expériences et sur une série d’entretiens avec les acteurs-clés du remembrement urbain. Après une analyse historique et juridique de l’outil, la note aborde le RU sous un angle plus opérationnel. En conclusion, les auteurs établissent une série de recommandations dressent quelques perspectives de développement. [less ▲]

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See detailComment un cours en PBL aide l'étudiant à devenir apprenant
Sadzot, Agnès ULiege; Massart, Valérie ULiege; Duchesnes, Christiane ULiege et al

in Ammar, Adil; Sbihi, Mohammed (Eds.) AIPU 2010 Réformes et changements pédagogiques dans l'enseignement supérieur (2010, May)

En 2006-2007, le cours d'Apprentissage de la Démarche Logopédique (ADL) est créé dans la formation en logopédie à l'Université de Liège. Il s'agit d’une approche clinique adoptant une méthodologie de type ... [more ▼]

En 2006-2007, le cours d'Apprentissage de la Démarche Logopédique (ADL) est créé dans la formation en logopédie à l'Université de Liège. Il s'agit d’une approche clinique adoptant une méthodologie de type Problem-Based Learning. En février 2009, une recherche par groupes focalisés a été réalisée dans le but d'évaluer l'impact de ce nouveau cours sur la formation clinique des étudiants. Les principaux résultats issus de cette recherche concernent le vécu des apprenants, et la façon dont les ADL ont modifié leur "métier d'étudiant". En effet, l'analyse des groupes focalisés suggère que les ADL permettent aux apprenants de développer des aptitudes transversales, telles que confiance en soi, capacités de communication, travail en équipe, esprit critique, organisation du travail, questionnement clinique, essentielles à la pratique professionnelle en logopédie. Par ailleurs, les ADL renforcent les liens entre théorie et pratique, en exigeant la mobilisation et la mise en réseau de toutes les connaissances acquises. [less ▲]

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See detailLes notions de monisme et dualisme
Behrendt, Christian ULiege

in Martens, Paul; Bossuyt, Marc (Eds.) Liber amicorum Michel Melchior (2010)

L'article décrit la portée de la distinction entre les notions de monisme et dualisme comme écoles de réception du droit international au sein de l'ordre juridique interne

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See detailAcide Hyaluronique et matrice extracellulaire : une molécule primitive ?
Nusgens, Betty ULiege

in Annales de Dermatologie et de Vénéréologie (2010), 137(supplément 1), 3-8

Hyaluronic acid, or hyaluronan, is a polymer made of the repetition of a unique disaccharidic unit, D-glucuronic acid and D-N-acetylglucosamine, that can reach a molecular mass of 10(7) daltons. This ... [more ▼]

Hyaluronic acid, or hyaluronan, is a polymer made of the repetition of a unique disaccharidic unit, D-glucuronic acid and D-N-acetylglucosamine, that can reach a molecular mass of 10(7) daltons. This primitive polymer has emerged as a remarkable extracellular matrix component by its viscoelastic properties, its hygroscopic capacities and the diversity of cell processes it controls. Identified in all vertebrate tissues, more than 50% of acid hyaluronic of the organism is present in skin. Having no protein core, its synthesis is performed through a unique process, depending on enzymatic activity of hyaluronan synthases acting at the internal face of the plasmatic membrane and extruding the nascent polymer to the extracellular medium. This polymer constitutes a scaffold on which a large number of sulfated proteoglycans, up to one hundred, can be linked. These supramolecular structures of considerable size are able to entrap large amounts of water and ions to provide tissues with hydration and turgescence. Hyaluronic acid is recognized by cell membrane receptors, notably CD44 which is the best known. Interaction of hyaluronic acid with its receptors triggers several intracellular signaling pathways regulating proliferation, migration and differentiation. Cell response is largely influenced by the size of the polymer and by that of the fragments generated upon degradation by hyaluronidases or free radicals. Hyaluronic acid is metabolically very active, as, for example, its half-life in skin is less than one day. Detected in epidermis where it could play a role in the control of proliferation and differentiation of basal cells, it is however prominent in dermis in association with versican. The remarkable physicochemical properties of hyaluronic acid as well as the diversity of biological processes it controls largely surpass the primitive character of this polymer. [less ▲]

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See detailLa filation biologique
Wautelet, Patrick ULiege

in Wautelet, Patrick (Ed.) Relations familiales internationales - l'actualité vue par la pratique (2010)

In this paper, I attempt to offer an overview of the main rules under Belgian law which deal with the establishment and the challenge of filiation links (parent-children relationship). This is done using ... [more ▼]

In this paper, I attempt to offer an overview of the main rules under Belgian law which deal with the establishment and the challenge of filiation links (parent-children relationship). This is done using 5 practical cases (inspiration for which has been found in practice and court reports) going from the most classic to more sophisticated situations. Some attention is also devoted to recent issues such as the consequences of using surrogacy arrangements with foreign mothers. [less ▲]

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See detailPartenariats, cohabitation légale et autres relations de vie commune
Wautelet, Patrick ULiege

in Wautelet, Patrick (Ed.) Relations familiales internationales - l'actualité vue par la pratique (2010)

In this paper, I offer an overview of the main questions which arise in relation with the so-called 'new forms' of marriage (such as same sex marriage and partnership), looking specifically at cross ... [more ▼]

In this paper, I offer an overview of the main questions which arise in relation with the so-called 'new forms' of marriage (such as same sex marriage and partnership), looking specifically at cross-border situations. An attempt is made to determine who has access to such legal relationships in Belgium, what are the consequences of such relationships in mixed relations and whether the newly created institutions are duly recognized as such abroad. [less ▲]

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See detailRecent developments in optimization of flexible components of multibody systems
Duysinx, Pierre ULiege; Emonds-Alt, Jonathan; Virlez, Geoffrey ULiege et al

Conference (2010, May)

Recently mechanical engineering has extended from a component to a system oriented approach. The structural analysis of components is now completed by the whole mechanical system simulation using ... [more ▼]

Recently mechanical engineering has extended from a component to a system oriented approach. The structural analysis of components is now completed by the whole mechanical system simulation using multibody system analysis. This evolution aims at capturing better the real loading conditions accounting for the component interaction and couplings in the system. Structural optimization is continuing along the same tracks. Recent works in structural optimization have tried to optimize components with respect to loadings conditions defined through dynamic loading coming from multibody system dynamic analysis. Generally, optimization techniques consider that the structural component is isolated from the rest of the mechanism and use simplified quasi-static load cases to mimic the complex loadings in service. In contrast, we have shown in previous works devoted to topology optimization that an optimization directly based on the dynamic response of the flexible multibody system leads to a more integrated approach. In order to overcome the limitations of some previous approaches, a more integrated optimization technique is proposed here, based on the nonlinear finite element approach for flexible multibody systems. The non linear finite element formalism accounts for both large rigid-body motions and elastic deflection of the structural components. In previous work, the optimal design of components was realized as an optimal truss / beam layout. The present communication investigates the optimal design of components considered as a continuum medium. We study first sizing optimal design of structural components and we later extend the method to optimal material distribution approach to address their lay out optimization. The continuum domain is discretized into finite elements. For sizing optimization, the design variables are wall-thickness and lumped element variables. For topology optimization the design variables are classically density-like parameters associated to a power law interpolation of effective material properties for intermediate densities, also known as Simply Isotropic Material with Penalization (SIMP). This study assesses the feasibility of this approach, which extends optimization techniques to continuum flexible bodies included in MBS. The numerical implementation is conducted in SAMCEF MECANO for the flexible MBS analysis and BOSS Quattro for the optimization shell. The nonlinear equations of motion are solved using a generalized-a time integration scheme while the sensitivity analysis of mechanical responses is based on a direct differentiation method or finite differences. For sizing and parametric optimization the paper investigates and compares several optimization approaches methods such as classical gradient-based methods (SQP, Augmented lagrangian), sequential convex programming methods (CONLIN, MMA), but also surrogate-based optimization method (with Neural Networks) combined with genetic algorithms. The formulation of the problem is also discussed, and its influence on the convergence history is illustrated. Optimal sizing, shape and topology optimization of a simple model of a robot are addressed. The optimization approach is illustrated on numerical applications of sizing optimization of robot arms during trajectory tracking and lightweight layout optimal design of automotive components. [less ▲]

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See detailSome misunderstood or unknown tricks (LaTeX)
Merciadri, Luca ULiege

in TUGboat (2010), 31(1), 76-78

Some very simple things to do in LATEX2e are often misunderstood (or simply unknown) to the –even skilled– writer. We here present some useful codes for 1. pedagogical uses: write a matrix with borders ... [more ▼]

Some very simple things to do in LATEX2e are often misunderstood (or simply unknown) to the –even skilled– writer. We here present some useful codes for 1. pedagogical uses: write a matrix with borders; show simplifications of terms in mathematical developments, 2. presenting data: make an accolade in a table, 3. solving the Springer’s tocdepth problem in svmono class, 4. writing european envelopes in an efficient way, 5. improving typography: the microtype package. [less ▲]

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See detailMultiparametric observations and analysis in the Bay of Calvi (Corsica), an ideal site for studying the human activity effects and climate changes in the Mediterranean Sea; STARESO
Gobert, Sylvie ULiege; Alvera Azcarate, Aïda ULiege; Barth, Alexander ULiege et al

Conference (2010, May)

STARESO (Station de REcherche Sous marine et Océanographique) is the marine and oceanographic research station of the University of Liège (Belgium) managed by the French company STARESO S.A.. Constructed ... [more ▼]

STARESO (Station de REcherche Sous marine et Océanographique) is the marine and oceanographic research station of the University of Liège (Belgium) managed by the French company STARESO S.A.. Constructed in 1969, it is located near Calvi (Corsica, Western Mediterranean Sea) in an oligotrophic area chosen for the exceptional quality of its coastal waters STARESO offers to the oceanographers, by diving or with boats, a direct access to the sea. The variety of the accessible ecosystems is remarkable and unique in the Mediterranean basin: -the Bay of Calvi is characterized by healthy and very diverse biocenosis (e.g. Posidonia meadows, rocky and sandy communities, -a steep submarine canyon, with depths greater than 1 000 meters, is accessible in 15 minutes of navigation; -the Liguro-Provençal front, a major hydrologic structure, is situated between 10 and 15 miles of the coast. STARESO is accessible all the year for everybody and is functioning like an oceanographic research vessel. The Station is a platform for all oceanographic disciplines with a scientific expertise widely based on a long tradition of interdisciplinary work, and a direct access to time series of physical, chemical and biological data registered with automated systems and variety of sensors deployed in the Bay of Calvi since 30 years. This platform provides the opportunity to reach coastal, pelagic, benthic, deep systems with a manageable cost and ship requirements in a pristine zone. [less ▲]

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See detailUpdating hydrogen fluoride (HF) FTIR time series above Jungfraujoch: comparison of two retrieval algorithms and impact of line shape models
Duchatelet, Pierre ULiege; Demoulin, Philippe ULiege; Hase, Frank et al

Poster (2010, May)

Fluorine enters the stratosphere mainly in the form of chlorofluorocarbons (CFCs; principally CFC-11 and CFC-12) and tetrafluoromethane (CF4), which have been widely emitted at ground level by human ... [more ▼]

Fluorine enters the stratosphere mainly in the form of chlorofluorocarbons (CFCs; principally CFC-11 and CFC-12) and tetrafluoromethane (CF4), which have been widely emitted at ground level by human activities over the past few decades. In the lower stratosphere, the photolysis of the long-lived CFC-11 (CCl3F) and CFC-12 (CCl2F2), whose emissions from the ground have been progressively phased out by the Montreal Protocol and its successive Amendments and Adjustments, leads to the formation of the two reservoirs: COClF and COF2. Subsequent photolysis of these two compounds then liberates F atoms, which could quickly react with CH4, H2O or H2 to form the extreme stable hydrogen fluoride (HF) gas. The formation of HF by these reactions is significant, as they make HF the largest fluorine reservoir in the middle and upper stratosphere. Despite the fact that fluorine does not directly participate in ozone depletion, measurements of the concentration of individual F-containing species at different altitude of the atmosphere are important as they reflect the amounts of anthropogenic gases – which also often bear ozone-threatening Cl atoms - transported into the middle atmosphere as well as their decomposition. Since the first detection of hydrogen fluoride in the Earth’s atmosphere by Zander (1975), several studies dealing with HF total column amounts derived from ground-based Fourier transform infrared (FTIR) observations at several latitudes in both hemispheres have been published. In addition, these last years have seen the emergence of more sophisticated retrieval algorithms (e.g. SFIT-2, PROFFIT) allowing to inverse total or partial columns as well as vertical distribution of the target gas from ground-based FTIR spectra. In this contribution, we propose to compare HF total columns derived from FTIR high-resolution ground-based observations performed at the Jungfraujoch (46.5°N, 8.0°E, 3580 m asl) by using two different retrieval codes: SFIT-2 v.3.91 and PROFFIT v.9.5. The impact of spectroscopic parameters (Voigt line shape model versus Galatry model line shape) on HF retrievals is also analyzed. References: Zander, R.: Présence de HF dans la stratosphère supérieure, C.R. Acad. Sci. Paris. Série B., 281, 213-214, 1975. [less ▲]

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See detailComparison of the error budgets associated with ground-based FTIR measurements of atmospheric CH4 profiles at Ile de la Réunion and Jungfraujoch
Vanhaelewyn, Gauthier; Duchatelet, Pierre ULiege; Vigouroux, Corinne et al

Poster (2010, May)

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See detailLittérature latine et banques de données : ne quid nimis
Denooz, Joseph ULiege

in Euphrosyne (2010), XXXVIII

The number of available digital versions of ancient Latin texts has increased in almost excessive proportions. These versions are recorded either on cd-roms (PHI3, BTL, Hyperbas-Lasla-Nice) or (more and ... [more ▼]

The number of available digital versions of ancient Latin texts has increased in almost excessive proportions. These versions are recorded either on cd-roms (PHI3, BTL, Hyperbas-Lasla-Nice) or (more and more frequently) on websites (e.g. The Latin Library, Intratext, Itinera electronica,…). It can be observed that most of these digitalised texts are actually not data banks but at the outmost text-bases that do not include any critical, lexicological, morphological, or syntactical information. Moreover these bases are often copied and pasted from each other, thus reproducing the same files with their qualities and flaws. The aim of the present article is to provide a description of what is available and to hoghlight both positive and negative aspects [less ▲]

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See detailLes indications de la toxine botulique chez l'enfant infirme moteur cérébral
Battisti, Oreste ULiege

Scientific conference (2010, May)

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See detailLorsque l'attachement mère-enfant est difficilie
Battisti, Oreste ULiege

Scientific conference (2010, May)

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See detailEvaluation du potentiel de récupération d’énergie à l’échappement d’un moteur TDI à l’aide d’un cycle de Rankine organique (ORC)
Declaye, Sébastien ULiege; Quoilin, Sylvain ULiege; Lemort, Vincent ULiege

Poster (2010, May)

Une étude expérimentale a été menée sur un cycle de Rankine organique de faible puissance (2,5kW). Les résultats expérimentaux ont permis de calibrer un modèle du cycle qui a ensuite été utilisé afin ... [more ▼]

Une étude expérimentale a été menée sur un cycle de Rankine organique de faible puissance (2,5kW). Les résultats expérimentaux ont permis de calibrer un modèle du cycle qui a ensuite été utilisé afin d’évaluer le potentiel de récupération d’énergie à l’échappement d’un moteur TDI pour 13 points de fonctionnement représentatifs. Les résultats montrent la possibilité de produire jusqu’à 2,4kW de puissance mécanique additionnelle. La fraction d’énergie récupérée (ERR) pouvant atteindre 6,8% de la puissance à l’arbre moteur. [less ▲]

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See detailIn silico study of the interaction of the Myelin Basic Protein C-terminal a-helical peptide with DMPC and mixed DMPC/DMPE lipid bilayers
Bessonov, Kyrylo ULiege

Conference (2010, May)

Biological membranes continue to be extensively investigated in different ways. This paper presents the benefits of Molecular Dynamics (MD) approaches to study the properties of biological membranes and ... [more ▼]

Biological membranes continue to be extensively investigated in different ways. This paper presents the benefits of Molecular Dynamics (MD) approaches to study the properties of biological membranes and proteins using the freely available GROMACS package, in the context of the Myelin Basic Protein (MBP) C-terminal a-helical peptide. A mixed membrane consisting of 2-Dimyristoyl-sn-Glycero-3-phosphocholine/1,2-Dimyristoyl-sn-Glycero-3- phosphoethanolamine (DMPC/DMPE), and pure DMPC membranes, composed of 188 and 248 lipids, respectively, were simulated for 200 ns at 309 K. The DMPC membrane was approximately three times more fluid compared to the DMPC/DMPE system, with the diffusion coefficients (D) being 0.0207x10-5 cm2/s and 0.0068x10-5 cm2/s, respectively. In addition, the 14-residue peptide representing the C-terminal a-helical region of murine Myelin Basic Protein (MBP), with amino acid sequence NH2-A141YDAQGTLSKIFKL154-COOH , was simulated in both membrane systems for 200 ns. The peptide penetrated further into the DMPC bilayer compared to the mixed DMPC/DMPE bilayer, potentially because of the reduced accessibility of the charged peptide amino acid side chains to the formal positive charge of the amine N atom surrounded by methyl and methylene groups in DMPC, that might have resulted in greater overall peptide mobility [3]. These findings are significant in their implication that membrane composition affects the behavior of MBP, providing further insights into myelin structure. Our preliminary results suggest that local changes in membrane composition (e.g. enrichment in DMPE molecules), as well as, electrostatic nature of primary amino acid sequence could cause localized denaturation / instability of external MBP a-helices possibly augmenting the degradation of myelin in multiple sclerosis (MS), resulting in a subsequent decrease of nerve impulse propagation efficiency. [less ▲]

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See detailOn the Convergence of Social Protection Performance in the European Union
Lefebvre, Mathieu ULiege

Scientific conference (2010, May)

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