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See detailSizing Photovoltaic Systems during Early Design A Decision Tool for Architects
Attia, Shady ULiege; De Herde, André

in Conference proceedings of American Solar Energy Society - 2010 (2010, May)

Despite all the available solar technologies and the opportunity to reduce energy demand, solar energy systems are in most cases not used in buildings today. The lack of technical knowledge among ... [more ▼]

Despite all the available solar technologies and the opportunity to reduce energy demand, solar energy systems are in most cases not used in buildings today. The lack of technical knowledge among architects is one of the main barriers according to the IEA-Task 41 entitled Solar Energy and Architecture [1]. In fact, several problems face architects during the design and set-up of buildings that integrate PV systems, for example, the complexity and uncertainty of estimating the PV performance. To overcome this problem and to examine these opportunities, this study developed a decision tool to guide architects to size PV systems during early design stages. The aim of the study was to help give architects a generic idea of the potential of PV as an energy source and how to integrate PV in the building architecture. The tool is based on a transient simulation database built using TRNSYS16 and underlies research considering PV technology parameters and local climatic conditions of Egypt. Simulations of three PV systems are compared with measured data in order to form a basis for optimal design and prediction of PV system performance. For this tool we developed and presented simple graphical visualization of the verified performance indices. For example, yearly maximum output energy of PV modules, for different inclinations and orientations for Aswan, Alexandria and Cairo. The overall benefit of this simple decision tool is informing and assisting architects and designers in order to increase the use of solar energy in buildings [less ▲]

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See detailUsing prior knowledge to accelerate online least-squares policy iteration
Busoniu, Lucian; De Schutter, Bart; Babuska, Robert et al

in Proceedings of the 2010 IEEE International Conference on Automation, Quality and Testing, Robotics (2010, May)

Reinforcement learning (RL) is a promising paradigm for learning optimal control. Although RL is generally envisioned as working without any prior knowledge about the system, such knowledge is often ... [more ▼]

Reinforcement learning (RL) is a promising paradigm for learning optimal control. Although RL is generally envisioned as working without any prior knowledge about the system, such knowledge is often available and can be exploited to great advantage. In this paper, we consider prior knowledge about the monotonicity of the control policy with respect to the system states, and we introduce an approach that exploits this type of prior knowledge to accelerate a state-of-the-art RL algorithm called online least-squares policy iteration (LSPI). Monotonic policies are appropriate for important classes of systems appearing in control applications. LSPI is a data-efficient RL algorithm that we previously extended to online learning, but that did not provide until now a way to use prior knowledge about the policy. In an empirical evaluation, online LSPI with prior knowledge learns much faster and more reliably than the original online LSPI. [less ▲]

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See detailInertie clinique et observance thérapeutique dans les valvulopathies chroniques du coeur gauche.
Moonen, Marie ULiege; Leroux, Aurélia ULiege; Lancellotti, Patrizio ULiege et al

in Revue Médicale de Liège (2010), 65(5-6), 290-8

Valvular heart diseases are of increasing importance among the general adult population. When compared with other heart diseases, there are few trials in the field of valvular heart disease and randomized ... [more ▼]

Valvular heart diseases are of increasing importance among the general adult population. When compared with other heart diseases, there are few trials in the field of valvular heart disease and randomized clinical trials are particularly scarce. Two sets of guidelines exist: one in the USA and the other in Europe. However, they are not always consistent due to the lack of randomized data and it appears that, frequently, there is a gap between the existing guidelines and their effective application. [less ▲]

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See detailCommunication financière : Un outil pour améliorer la liquidité des entreprises françaises
Sougné, Danielle ULiege; Ajina, Aymen ULiege

in Revue Banque = Banque Magazine (2010)

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See detailInfluence de l'ajout de co-solvant pour l'estérification du D-mannose et de l'acide D-glucuronique assistée par les lipases
Richard, Gaetan ULiege; Brognaux, Alison ULiege; Nott, Katherine ULiege et al

Poster (2010, May)

En parallèle à la production de biocarburant, le second objectif du bioraffinage est la transformation des sucres issus de l’hydrolyse de la lignocellulose en produits d’intérêt, qui se substitueront aux ... [more ▼]

En parallèle à la production de biocarburant, le second objectif du bioraffinage est la transformation des sucres issus de l’hydrolyse de la lignocellulose en produits d’intérêt, qui se substitueront aux produits de la vie courante issus du pétrole. L’une des voies de valorisation envisageable est la synthèse de molécules amphiphiles par greffage de chaînes grasses sur le sucre. Ces composés trouveraient alors des applications dans de très nombreux domaines utilisant les tensioactifs (alimentaire, détergence, peinture,…) . Dans le cadre du programme d’excellence TECHNOSE et du projet d’Action de Recherche Concertées SUPERZYM, deux sucres ont été testés : un polyol, le D-mannose, et un sucre acide, l’acide D-glucuronique. Afin de conférer un caractère amphiphile à la molécule, les lipases ont été utilisées en tant qu’outils d’estérification. Ces triglycérides hydrolases sont en effet capables de catalyser ce type de réaction, et de nombreux exemples dans la littérature démontrent le fort potentiel industriel de ces enzymes , . L’estérification du D-mannose et de l’acide D-glucuronique a donc été mise en œuvre en présence de la lipase de Candida antarctica B (Novozyme 435). La réaction est effective, mais l’ajout de co-solvants tels que la pyridine ou le DMSO améliore les vitesses initiales et les rendements de la réaction. Ces améliorations seront discutées et comparées sur ce poster. [less ▲]

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See detailGenerating informative trajectories by using bounds on the return of control policies
Fonteneau, Raphaël ULiege; Murphy, Susan; Wehenkel, Louis ULiege et al

in Proceedings of the Workshop on Active Learning and Experimental Design 2010 (in conjunction with AISTATS 2010) (2010, May)

We propose new methods for guiding the generation of informative trajectories when solving discrete-time optimal control problems. These methods exploit recently published results that provide ways for ... [more ▼]

We propose new methods for guiding the generation of informative trajectories when solving discrete-time optimal control problems. These methods exploit recently published results that provide ways for computing bounds on the return of control policies from a set of trajectories. [less ▲]

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See detailThe earthquake sedimentary record of the Marmara Sea, Turkey
Drab, Laureen; Hubert, Aurelia ULiege; Schmidt, Sabine et al

in Geophysical Research Abstracts (2010, May)

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See detailNew simplified analytical method for the Prediction of global stability of steel and composite sway frames
Demonceau, Jean-François ULiege; Ly, Dong Phuong Lam ULiege; Coméliau, Ludivine ULiege et al

in Proceedings of the annaual stability conference, 2010 (2010, May)

Eurocode 4 is the European design code for composite construction; in its so-called EN 1994-1-1 version, the design of “non-sway buildings” is mainly covered. As a result, EC4 focuses on the check of ... [more ▼]

Eurocode 4 is the European design code for composite construction; in its so-called EN 1994-1-1 version, the design of “non-sway buildings” is mainly covered. As a result, EC4 focuses on the check of structural elements like beams, columns, slabs and joints. However, in the last years, the construction of taller buildings and larger industrial halls without wind bracing systems tends to make global instability a relevant failure mode, which is not well covered by Eurocode 4. Recently, intensive experimental, numerical and theoretical investigations have been carried out at Liège University. The latter aimed at improving the knowledge in the field of sway composite building frames and at developing appropriate design rules. The rotational behavior of the beam-to-column composite joints is one of the key aspects of the problem to which a special attention has been paid. This paper reflects investigations carried out at Liege University on this topic. In particular, an innovative simplified analytical method to predict the ultimate loading factor and the associated collapse mode of both steel and composite frames subjected to static loadings is presented. [less ▲]

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See detailApproximate dynamic programming with a fuzzy parameterization
Busoniu, Lucian; Ernst, Damien ULiege; De Schutter, Bart et al

in Automatica (2010), 46(5), 804-814

Dynamic programming (DP) is a powerful paradigm for general, nonlinear optimal control. Computing exact DP solutions is in general only possible when the process states and the control actions take values ... [more ▼]

Dynamic programming (DP) is a powerful paradigm for general, nonlinear optimal control. Computing exact DP solutions is in general only possible when the process states and the control actions take values in a small discrete set. In practice, it is necessary to approximate the solutions. Therefore, we propose an algorithm for approximate DP that relies on a fuzzy partition of the state space, and on a discretization of the action space. This fuzzy Q-iteration algorithm works for deterministic processes, under the discounted return criterion. We prove that fuzzy Q-iteration asymptotically converges to a solution that lies within a bound of the optimal solution. A bound on the suboptimality of the solution obtained in a finite number of iterations is also derived. Under continuity assumptions on the dynamics and on the reward function, we show that fuzzy Q-iteration is consistent, i.e., that it asymptotically obtains the optimal solution as the approximation accuracy increases. These properties hold both when the parameters of the approximator are updated in a synchronous fashion, and when they are updated asynchronously. The asynchronous algorithm is proven to converge at least as fast as the synchronous one. The performance of fuzzy Q-iteration is illustrated in a two-link manipulator control problem. [less ▲]

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See detailIdentification of Deep sea Flora on Video Imagery
Carré, Cyril ULiege

Scientific conference (2010, May)

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See detailCoordinated motion design on Lie groups
Sarlette, Alain ULiege; Bonnabel, Silvere; Sepulchre, Rodolphe ULiege

in IEEE Transactions on Automatic Control (2010), 55(5), 1047-1058

The present paper proposes a unified geometric framework for coordinated motion on Lie groups. It first gives a general problem formulation and analyzes ensuing conditions for coordinated motion. Then, it ... [more ▼]

The present paper proposes a unified geometric framework for coordinated motion on Lie groups. It first gives a general problem formulation and analyzes ensuing conditions for coordinated motion. Then, it introduces a precise method to design control laws in fully actuated and underactuated settings with simple integrator dynamics. It thereby shows that coordination can be studied in a systematic way once the Lie group geometry of the configuration space is well characterized. Applying the proposed general methodology to particular examples allows to retrieve control laws that have been proposed in the literature on intuitive grounds. A link with Brockett's double bracket flows is also made. The concepts are illustrated on SO(3) , SE(2) and SE(3). [less ▲]

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See detailModelling the thermal efficiency of condensing boilers working in steady-state conditions
Makaire, Danielle ULiege; Ngendakumana, Philippe ULiege

Scientific conference (2010, May)

The structure of the model is similar to the model of a conventional boiler model with a main counterflow gas-water heat exchanger (HX1), at which a condensing heat exchanger is added (HX2). The case ... [more ▼]

The structure of the model is similar to the model of a conventional boiler model with a main counterflow gas-water heat exchanger (HX1), at which a condensing heat exchanger is added (HX2). The case losses to the ambient is neglected. Prior to the second heat exchanger (HX2), the exhaust gas are converted to equivalent wet air as the wet heat exchanger is simulated by a cooling coil used in air treatment. The model has been validated experimentally on gas- and oil-fired boilers. Calculated thermal efficiencies agree very well with experimental results. [less ▲]

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See detailThoughts on fetal growth: tissues and nutrition
Battisti, Oreste ULiege

Conference (2010, May)

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See detailUne approche théorique contingente du design des systèmes de contrôle de gestion : le cas des collectivités locales du Bénin
Togodo Azon, Degodo Aimé ULiege; Van Caillie, Didier ULiege; Pichault, François ULiege

in Association Francophone de Comptabiltélité (Ed.) Actes du 31ème Congrès de l'Association Francophone de Comptabilité (2010, May)

The current paper aims to elaborate a theoretical research model on the determinants of the management control systems in local collectivities in Sub-Sahara Africa. A critical state of the art allowed us ... [more ▼]

The current paper aims to elaborate a theoretical research model on the determinants of the management control systems in local collectivities in Sub-Sahara Africa. A critical state of the art allowed us to conclude that (1) organizational factors and (2) non organizational factors as the global institutional framework (the legal and regulatory pressures, the financial pressures and the political pressures) and the sociocultural framework (the domestic and group pressures, the ethnic pressures, the religious pressures and the pressures due to localization) are the major key determinants in the elaboration, the adoption and the efficiency of the Management Control System in local Sub-Saharian collectivities. [less ▲]

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See detailDynamic Nucleocytoplasmic Shuttling of an Arabidopsis SR Splicing Factor: Role of the RNA-Binding Domains
Rausin, Glwadys ULiege; Tillemans, Vinciane ULiege; Stankovic, Nancy ULiege et al

in Plant Physiology (2010), 153

Serine/arginine-rich (SR) proteins are essential nuclear-localized splicing factors. We have investigated the dynamic subcellular distribution of the Arabidopsis (Arabidopsis thaliana) RSZp22 protein, a ... [more ▼]

Serine/arginine-rich (SR) proteins are essential nuclear-localized splicing factors. We have investigated the dynamic subcellular distribution of the Arabidopsis (Arabidopsis thaliana) RSZp22 protein, a homolog of the human 9G8 SR factor. Little is known about the determinants underlying the control of plant SR protein dynamics, and so far most studies relied on ectopic transient overexpression. Here, we provide a detailed analysis of the RSZp22 expression profile and describe its nucleocytoplasmic shuttling properties in specific cell types. Comparison of transient ectopic- and stable tissue-specific expression highlights the advantages of both approaches for nuclear protein dynamic studies. By site-directed mutagenesis of RSZp22 RNA-binding sequences, we show that functional RNA recognition motif RNP1 and zinc-knuckle are dispensable for the exclusive protein nuclear localization and speckle-like distribution. Fluorescence resonance energy transfer imaging also revealed that these motifs are implicated in RSZp22 molecular interactions. Furthermore, the RNA-binding motif mutants are defective for their export through the CRM1/XPO1/Exportin-1 receptor pathway but retain nucleocytoplasmic mobility. Moreover, our data suggest that CRM1 is a putative export receptor for mRNPs in plants. [less ▲]

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See detailImmunohistochemical investigation of cells expressing CD21, membrane IgM, CD32, and a follicular dendritic cell marker in the lymphoid tissues of neonatal calves
Chattha, K. S.; Hodgins, D. C.; DeLay, J. et al

in Veterinary Immunology and Immunopathology (2010), 137

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