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See detailDetecting with PMUs the onset of voltage instability caused by a large disturbance
Glavic, Mevludin; Van Cutsem, Thierry ULg

(2008, July)

This paper deals with long-term voltage instability triggered by the outage of transmission or generation equipments. It is shown how the onset of voltage instability could be detected in real-time from ... [more ▼]

This paper deals with long-term voltage instability triggered by the outage of transmission or generation equipments. It is shown how the onset of voltage instability could be detected in real-time from post-disturbance bus voltages provided by Phasor Measurement Units (PMUs), assuming observability of the whole region prone to voltage instability. An extended set of equilibrium equations is fitted to the measurements and the change in sign of sensitivities is onitored. The latter are easily computed even for a large system. The important effects of overexcitation limiters and load tap changers are taken into account. The approach is illustrated on a 52-bus 20-machine system, where PMU outputs are simulated from detailed time simulation. [less ▲]

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See detailGlobal synchronization on the circle
Sarlette, Alain ULg; Tuna, Sezai Emre; Blondel, Vincent et al

in Proceedings of the 17th IFAC World Congress (2008, July)

The convexity arguments used in the consensus literature to prove synchronization in vector spaces can be applied to the circle only when all agents are initially located on a semicircle. Existing ... [more ▼]

The convexity arguments used in the consensus literature to prove synchronization in vector spaces can be applied to the circle only when all agents are initially located on a semicircle. Existing strategies for (almost-)global synchronization on the circle are either restricted to specific interconnection topologies or use auxiliary variables. The present paper first illustrates this problem by showing that weighted, directed interconnection topologies can be designed to make any reasonably chosen configuration of the agents on the circle a stable equilibrium of a basic continuous-time consensus algorithm. Then it proposes a so-called “gossip algorithm”, which achieves global asymptotic synchronization on the circle with probability 1 for a large class of interconnections, without using auxiliary variables, thanks to the introduction of randomness in the system. [less ▲]

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See detailCurrent Trends in the Research on Physical Education Teacher Education (PETE)
Cloes, Marc ULg

Conference (2008, July)

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See detailEffects of small-scale atmospheric activity on precise positioning
Wautelet, Gilles ULg; Lejeune, Sandrine; Stankov, Stanimir et al

Report (2008)

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See detailMoins, mieux et autrement : Maintenant !
Ozer, Pierre ULg; Perrin, Dominique ULg

Article for general public (2008)

Veiller à la composition de notre assiette et être attentif à nos modes de déplacements sont deux éléments clefs qui font partie des multiples petits actes citoyens que nous pouvons poser pour participer ... [more ▼]

Veiller à la composition de notre assiette et être attentif à nos modes de déplacements sont deux éléments clefs qui font partie des multiples petits actes citoyens que nous pouvons poser pour participer à l’effort mondial de lutte contre le réchauffement climatique. Refuser de s’adapter ne reflète que notre opiniâtreté à vouloir nous emmitoufler dans un mode de vie qui n’est plus viable et notre incapacité à se détourner d’une société d’auto-consumation. [...] [less ▲]

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See detailMerging academic libraries: An opportunity for a face-lift?
Durieux, Nancy ULg; Vandenput, Sandrina ULg; Brouwir, Christine ULg et al

Conference (2008, June 26)

Although the decision to merge libraries generates stress, it is also a great opportunity to start a global reflection on the functioning of libraries. In 2003, the University of Liège decided to create a ... [more ▼]

Although the decision to merge libraries generates stress, it is also a great opportunity to start a global reflection on the functioning of libraries. In 2003, the University of Liège decided to create a new physical and functional structure by combining the previously independent libraries of Medicine, Veterinary Medicine, Botany, Zoology, Psychology and Educational Sciences. The initial phase included a plan to remove the collections and standardise the academic teaching of IT literacy in the various disciplines. We now want to question our missions and evaluate our present working procedures in order to optimise our services, eventually develop new ones, and make them visible through a new website or any other types of support. The different populations of users need to be clearly identified, evaluated and anticipated. Staff competences must be evaluated to guarantee that users' expectations are met, and possibly to envisage any new services that may need to be created. In addition, staff competences must be improved through adapted education and tailored professional training. At the same time, the library involvement in academic teaching deserves to be properly highlighted. We are aware that there is not anything new in such an approach, but the pieces of evidence are scattered, outdated or not adapted to our present situation. As a consequence, we propose an overview of the literature concerning the marketing of academic libraries, conducted according to the principles of Evidence-Based Library and Information Practice. We shall select the most important publications providing strong theoretical support, and we shall collect existing tools, evaluation grids and procedure rules that might be useful during any step of the project. We shall organise them into a structured and pragmatic working strategy that could be used by any library interested in a marketing approach. It should integrate the different topics previously mentioned such as the library’s missions, the evaluation and optimisation of services, as well as the visibility of the teaching activities and the professional education programmes developed by academic libraries. [less ▲]

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See detailFair Trade Organisations in Europe: A Significant Field of Social Enterprise?
Huybrechts, Benjamin ULg

Conference (2008, June 26)

With the help of examples of FTOs in Belgium, France, Italy and the UK, we have applied some of the features of SE approaches to the context of FT. It appears that FTOs are particularly significant ... [more ▼]

With the help of examples of FTOs in Belgium, France, Italy and the UK, we have applied some of the features of SE approaches to the context of FT. It appears that FTOs are particularly significant examples of SEs, combining in different ways economic, social and sometimes political dimensions. From more NGO-like to more business-like configurations, all FTOs of our sample seem to respect the key features of SEs, under which the primacy of 23 the social mission, the limited (if any) profit distribution, the focus on innovation and at least some degree of self-financing. Nevertheless, there is some heterogeneity in terms of FTOs’ goals and activities. While all FTOs seem to combine, at least, economic and social dimensions – although at varying degrees and forms –, the political dimension is not present in the same way for all FTOs. Pioneer FTOs generally conduct education and advocacy activities in a developed and explicit way. Newcomer FTOs, however, have heterogeneous profiles in terms of political involvement, as the positioning seems to depend much on the entrepreneur’s choices. In terms of governance, practices are also very diverse in terms of leaders’ profiles, legal forms and stakeholders’ involvement in the decision-making structures. Some FTOs are quasi-individual ventures and are thus close to some American approaches of SE. Other FTOs are much more multi-stakeholder and fit better in the EMES conceptualisation of SE. The governance structure also seems to reflect to a certain extent the positioning of the FTO towards the different dimensions of FT. FTOs led by activists and having volunteers or partner NGOs on their Board seem to have a stronger focus on non-economic (social and political) goals. In the other sense, very economic-oriented FTOs are often run by managers with a business background and governed by their manager and/or their shareholders. As a conclusion, this article has tried to provide some theoretical and empirical support to the implicit link that has been established, both in the academic world and in the field practice, between FT and SE. The diversity of the FT sector echoes the rich diversity of SEs’ practices and conceptualisations. In such sense, considering FTOs as SEs is probably made easier because of the wide and flexible theoretical framework of SE – few authors claiming to have a “definition” of SE. If more restricted conceptions of SE were to emerge – e.g., the limitation of SE to formal Third Sector legal forms, or to 100% market financing –, then part of the FTOs would be excluded from the SE area. In such sense, FT appears as an important laboratory the evolutions of which can feed the theoretical construction of SE. [less ▲]

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See detailLe modèle belge de concertation budgétaire
Husson, Jean-François ULg

Conference (2008, June 25)

Cette présentation aborde l'historique de la coordination budgétaire en Belgique depuis le début des années 1990. Elle s'attarde plus particulièrement sur les institutions de coordination (Comité de ... [more ▼]

Cette présentation aborde l'historique de la coordination budgétaire en Belgique depuis le début des années 1990. Elle s'attarde plus particulièrement sur les institutions de coordination (Comité de consertation, Conseil supérieur des Finances,...) et les divers instruments de régulation utilisés. [less ▲]

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See detailNew pH-sensitive flower micelles for drug delivery systems
Cajot, Sébastien ULg; Van Butsele, Kathy; Jérôme, Christine ULg

Poster (2008, June 23)

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See detailManufacturing and verification of ZnS and Ge prisms for the JWST MIRI imager
Rossi, Laurence ULg; Renotte, Etienne ULg; Plesseria, Jean-Yves ULg et al

in Proceedings of SPIE (2008, June 23), 7018

The JWST Mid-Infrared Instrument (MIRI) is designed to meet the JWST science requirements for mid-IR capabilities and includes an Imager MIRIM provided by CEA (France). A double-prism assembly (DPA ... [more ▼]

The JWST Mid-Infrared Instrument (MIRI) is designed to meet the JWST science requirements for mid-IR capabilities and includes an Imager MIRIM provided by CEA (France). A double-prism assembly (DPA) allows MIRIM to perform low-resolution spectroscopy. The MIRIM DPA shall meet a number of challenging requirements in terms of optical and mechanical constraints, especially severe optical tolerances, limited envelope and very high vibration loads. <br />The University of Cologne (Germany) and the Centre Spatial de Liege (Belgium) are responsible for design, manufacturing, integration, and testing of the prism assembly. A companion paper (Fischer et al. 2008) is presenting the science drivers and mechanical design of the DPA, while this paper is focusing on optical manufacturing and overall verification processes. <br />The first part of this paper describes the manufacturing of Zinc-sulphide and Germanium prisms and techniques to ensure an accurate positioning of the prisms in their holder. (1) The delicate manufacturing of Ge and ZnS materials and (2) the severe specifications on the bearing and optical surfaces flatness and the tolerance on the prism optical angles make this process innovating. The specifications verification is carried out using mechanical and optical measurements; the implemented techniques are described in this paper. <br />The second part concerns the qualification program of the double-prism assembly, including the prisms, the holder and the prisms anti-reflective coatings qualification. Both predictions and actual test results are shown. [less ▲]

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See detailRobustness of structures - behaviour of composite joints
Demonceau, Jean-François ULg; Jaspart, Jean-Pierre ULg

in Sixth International Workshop on Connections in Steel Structures (2008, June 23)

Recent events such as natural catastrophes or terrorism attacks have highlighted the necessity to ensure the structural integrity of buildings under exceptional loading. Accordingly, a European RFCS ... [more ▼]

Recent events such as natural catastrophes or terrorism attacks have highlighted the necessity to ensure the structural integrity of buildings under exceptional loading. Accordingly, a European RFCS project entitled “Robust structures by joint ductility” has been set up in 2004, for three years, with the aim to provide requirements and practical guidelines to ensure the structural integrity of steel and composite structures under exceptional loading through an appropriate robustness. In this project, the importance of the structural joints has been shown; indeed, these ones experience additional high tying forces after the loss of a column, as a result of the development of membrane forces in the beams located just above the damaged column. Moreover a reversal of moments occurs in some joints. In this paper design models for the evaluation of the mechanical properties of joints in such extreme situations are presented. References are made to recent tests on joints in isolation recently achieved in the framework of the above-mentioned RFCS project. [less ▲]

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See detailThe Driver Model of the traffic flow simulation PELOPS – modelling and application possibilities
Christen, Fréderic ULg; Huang, Q.

in 2nd Berlin Expert Conference on Driver Modelling “Driver Modelling in Science and Economy” (2008, June 20)

In diesem Beitrag wird zunächst das Verkehrssimulationsprogramms PELOPS vorgestellt. Dabei wird detailliert auf das in PELOPS enthaltene Fahrermodell eingegangen. Das Modell ist in der Lage, sowohl ... [more ▼]

In diesem Beitrag wird zunächst das Verkehrssimulationsprogramms PELOPS vorgestellt. Dabei wird detailliert auf das in PELOPS enthaltene Fahrermodell eingegangen. Das Modell ist in der Lage, sowohl einspuriges Folgeverhalten, als auch das Fahrverhalten beispielsweise bei Spurwechselmanövern realistisch abzubilden. Nach der Beschreibung des Modells wird die Methodik zur Entwicklung und Implementierung neuer Fahrermodellfunktionen erläutert. Hierbei werden die Vor- und Nachteile bei der Erfassung des Fahrerverhaltens anhand von Induktionsschleifen, Videodektionsanlagen, Fahrsimulatoren oder Messfahrzeugen beschrie- ben. Abschließend umreißt der Beitrag zwei Applikationsmöglichkeiten des Fahrermodells: Zum einen den Einsatz des Fahrermodells im Fahrsimulator und zum anderen die Integration des Fahrermodells als Reglers im Fahrzeug. [less ▲]

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See detailReproducible Testing of Distributed Software with Middleware Virtualization and Simulation
Briquet, Cyril ULg; de Marneffe, Pierre-Arnoul ULg

in Ur, Shmuel (Ed.) Proceedings of the 6th Workshop on Parallel And Distributed systems: Testing, Analysis, and Debugging (2008, June 20)

P2P Grids are Grids organized into P2P networks where participant exchange computing time so as to complete computational tasks. Evaluating the performance of scheduling algorithms enables one to deploy ... [more ▼]

P2P Grids are Grids organized into P2P networks where participant exchange computing time so as to complete computational tasks. Evaluating the performance of scheduling algorithms enables one to deploy those that are efficient. Performance is often evaluated experimentally or through simulation because these algorithms (typically heuristics) are too complex to model analytically. Testing the implementation of P2P Grid middleware before it is deployed is also important: Reproducing configurations or conditions that lead to unexpected outcomes is thus valuable. A P2P Grid environment exhibits multiple sources of failure and is typically dynamic and uncontrollable. Reproducing even basic behavior of Grid nodes in a controllable and repeatable manner is thus exceedingly difficult. Such lack of control over the environment is a major challenge in the software engineering of P2P Grid middleware. Simulators have been proposed to evaluate the performance of scheduling algorithms, but are often limited in scope, reusability and accuracy, i.e. they rely on simplified models. We introduce a software engineering pattern - that we call code once, deploy twice - to both reduce the distance between simulated and implemented algorithms and reproduce, at will, Grid configurations and environments: A simulator implementation of a Grid architecture is built by virtualizing its middleware implementation. An immediate benefit is that most of the code can be reused between both implementations; only communications between Grid nodes, multithreading within Grid nodes and actual task execution are coded differently. As a derived benefit, most of the code of the middleware can be tested within the controlled environment of the simulator, before it is deployed as-is. Another benefit is high simulation accuracy. We describe the implementation of a P2P Grid following the code once, deploy twice pattern, that we believe is also relevant to other Grid types (certainly Volunteer Grids and Desktop Grids, and possibly Globus-based Grids). [less ▲]

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See detailSur le concept de "valeur pure" chez Ferdinand de Saussure
Sofia, Estanislao ULg

Conference (2008, June 17)

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See detailImportation de notices BIB dans ALEPH & création de HOL et Z30 : retour d'expériences
Renaville, François ULg

Conference given outside the academic context (2008)

Synthèse de quelques expériences du Réseau des Bibliothèques de l'Université de Liège, entre mai 2007 et mai 2008, en matière d'importation de notices bibliographiques (intégration d'un catalogue ... [more ▼]

Synthèse de quelques expériences du Réseau des Bibliothèques de l'Université de Liège, entre mai 2007 et mai 2008, en matière d'importation de notices bibliographiques (intégration d'un catalogue, importation d'e-journaux, importation d'e-books) et de création de notices holdings et d'exemplaires. Avec exemples de scripts utilisés. - Analyse de la qualité des données ; - Créer un fichier en ALEPH séquentiel (services ALEPH & conversion xls -> ALEPH séquentiel) ; - Importation de notices BIB (manage-18) et exemples de scripts correctifs et d'amélioration ; - Manage-50 (création de Z30 et HOL) ; - Manage-500 (création de HOL seuls). [less ▲]

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See detailIMPROVE - Design of Improved and Competitive Products
Giuglea, S.; Chirica, I.; Giuglea, V. et al

in DBlaS'2008, I&CT Intern. Conf. (2008)

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See detailDiversity of planktonic cyanobacteria and microcystin occurrence in Polish water bodies investigated using a polyphasic approach
Boutte, Christophe; Mankiewicz-Boczek, Joanna; Komarkova, Jarka et al

in Aquatic Microbial Ecology (2008), 51

Microscopic measurements of fresh biomass and 16S rRNA gene sequences from clone libraries and denaturing gradient gel electrophoresis (DGGE) were used to investigate cyanobacterial diversity in Polish ... [more ▼]

Microscopic measurements of fresh biomass and 16S rRNA gene sequences from clone libraries and denaturing gradient gel electrophoresis (DGGE) were used to investigate cyanobacterial diversity in Polish water bodies in 2002. In addition, measurements of microcystin (MC) concentrations were made. Thirty water samples were taken from 11 water bodies; of these samples, 18 were obtained from the Sulejow Reservoir during regular monitoring from June to October. Intraand extracellular MC concentrations in Sulejow samples were measured by high performance liquid chromatography (HPLC). The extracellular MC concentration was assessed using a protein phosphatase inhibition assay (PPIA) in additional lakes. Additionally, physicochemical parameters were measured (total nitrogen [TN], total phosphorus [TP], TN:TP ratio, chlorophyll a concentration, temperature). In Sulejow, high intracellular MC concentrations corresponded to large cyanobacterial biovolumes and to low TN:TP ratios. In the other lakes, extracellular MCs were not linked to any measured parameters. The combination of the microscopic and molecular data showed that Aphanizomenon and Microcystis were the dominant genera during the summer period in the Sulejow Reservoir. At the genetic level, there was a succession of 2 different operational taxonomic units (OTUs) belonging to the lineage Anabaena/Aphanizomenon. In the other water bodies, the most frequent populations were Aphanizomenon, Anabaena, Microcystis and Planktothrix. Small populations of Romeria, Snowella, Woronichinia, Limnothrix and Pseudanabaena were observed, and an enigmatic cluster affiliated with Prochlorothrix was genetically retrieved. Anabaena and Microcystis were presumed to be the main genera responsible for the MC production. [less ▲]

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