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See detailDark atoms and the positron-annihilation-line excess in the galactic bulge
Cudell, Jean-René ULg; Khlopov, Maxim; Wallemacq, Quentin ULg

in Advances in High Energy Physics (in press), 2014

It was recently proposed that stable particles of charge -2, O^{--}, can exist and constitute dark matter after they bind with primordial helium in O-helium (OHe) atoms. We study here in details the ... [more ▼]

It was recently proposed that stable particles of charge -2, O^{--}, can exist and constitute dark matter after they bind with primordial helium in O-helium (OHe) atoms. We study here in details the possibility that this model provides an explanation for the excess of gamma radiation in the positron-annihilation line from the galactic bulge observed by INTEGRAL. This explanation assumes that OHe, excited to a 2s state through collisions in the central part of the Galaxy, de-excites to its ground state via an E0 transition, emitting an electron-positron pair. The cross section for OHe collisions with excitation to 2s level is calculated and it is shown that the rate of such excitations in the galactic bulge strongly depends not only on the mass of O-helium, which is determined by the mass of O^{--}, but also on the density and velocity distribution of dark matter. Given the astrophysical uncertainties on these distributions, this mechanism constrains the O^{--} mass to lie in two possible regions. One of these is reachable in the experimental searches for stable multicharged particles at the LHC. [less ▲]

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See detailThe soundtrack of RR Lyrae in Omega Cen at high-frequency
Calamida, A.S.; Randall, S.K.; Monelli, M. et al

in Memorie della Società Astronomica Italiana : Journal of the Italian Astronomical Society (in press)

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See detailCompte rendu de D. van Mal-Maeder, A. Burnier, L. Núñez (éds.): Jeux de voix. Énonciation, intertextualité et intentionnalité dans la littérature antique
Macedo, Gabriel ULg

in Antiquité Classique : Revue Interuniversitaire d'Etudes Classiques (in press)

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See detailCosmological constraints on mirror matter parameters
Ciarcelluti, Paolo; Wallemacq, Quentin ULg

in Advances in High Energy Physics (in press), 2014

Up-to-date estimates of the cosmological parameters are presented as a result of numerical simulations of cosmic microwave background and large scale structure, considering a flat Universe in which the ... [more ▼]

Up-to-date estimates of the cosmological parameters are presented as a result of numerical simulations of cosmic microwave background and large scale structure, considering a flat Universe in which the dark matter is made entirely or partly of mirror matter, and the primordial perturbations are scalar adiabatic and in linear regime. A statistical analysis using the Markov Chain Monte Carlo method allows to obtain constraints of the cosmological parameters. As a result, we show that a Universe with pure mirror dark matter is statistically equivalent to the case of an admixture with cold dark matter. The upper limits for the ratio of the temperatures of ordinary and mirror sectors are around 0.3 for both the cosmological models, that show the presence of a dominant fraction of mirror matter, 0.06 < Ω_{mirror} h^2 < 0.12. [less ▲]

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See detailRéexamen du dessin du codex miscellaneus de Montserrat (P. Montserrat inv. nr. 154 = MP³ 2916.41)
Macedo, Gabriel ULg

in Aegyptus (in press), 90

New interpretation of the drawing of a mythological hero in the 4th Montserrat codex miscellaneus.

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See detailLes animateurs de la vie littéraire en Belgique francophone : de leur rôle interne à leur position de médiateur transnational
Dozo, Björn-Olav ULg

in Blanchard, Nelly; Thomas, Mannaig (Eds.) Des littératures périphériques (in press)

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See detailLe Fonds Hubert Nyssen à l'Université de Liège
Durand, Pascal ULg; Habrand, Tanguy ULg

in Histoires littéraires (in press)

Biographie croisée de l'écrivain et de l'éditeur Hubert Nyssen et présentation détaillée du Fonds d'archives déposé par lui au Centre d'Etude du Livre Contemporain de l'Université de Liège.

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See detailImpact of vocal load on breathiness: Perceptual evaluation
Remacle, Angélique ULg; Schoentgen, Jean; FINCK, Camille ULg et al

in Logopedics, Phoniatrics, Vocology (in press)

Objectives: To evaluate the impact on voice of 2 hours of continuous oral reading. Methods: Fifty normophonic women underwent two sessions of voice loading in which the required intensity level varied: 60 ... [more ▼]

Objectives: To evaluate the impact on voice of 2 hours of continuous oral reading. Methods: Fifty normophonic women underwent two sessions of voice loading in which the required intensity level varied: 60-65 dB(A) for the first session, and 70-75 dB(A) for the second session. Ten expert judges evaluated the breathiness of one sentence recorded before and after each loading session. Pairs of stimuli were presented randomly to the judges, who were asked to designate the breathiest sample. Results: A significant decrease in breathiness was observed following both sessions, suggesting an improvement of voice subsequent to loading. When comparing the two intensity levels, no difference was found for breathiness after vocal loading. [less ▲]

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See detailA Balance Equation Determines a Switch in Neuronal Excitability
Franci, Alessio ULg; Drion, Guillaume ULg; Seutin, Vincent ULg et al

in PLoS Computational Biology (in press)

We use the qualitative insight of a planar neuronal phase portrait to detect an excitability switch in arbitrary conductance-based models from a simple mathematical condition. The condition expresses a ... [more ▼]

We use the qualitative insight of a planar neuronal phase portrait to detect an excitability switch in arbitrary conductance-based models from a simple mathematical condition. The condition expresses a balance between ion channels that provide a negative feedback at resting potential (restorative channels) and those that provide a positive feedback at resting potential (regenerative channels). Geometrically, the condition imposes a transcritical bifurcation that rules the switch of excitability through the variation of a single physiological parameter. Our analysis of six di erent published conductance based models always nds the transcritical bifurcation and the associated switch in excitability, which suggests that the mathematical predictions have a physiological rel- evance and that a same regulatory mechanism is potentially involved in the excitability and signaling of many neurons. [less ▲]

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See detailLe rôle de la perception de soi comme lecteur dans le développement de la compétence en lecture
Schillings, Patricia ULg; Dupont, Virginie; Neuberg, France ULg et al

in Mesure et Evaluation en Education [=MEE] (in press)

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See detailMODEL PREDICTIVE CONTROL OF CONGESTION AND VOLTAGE PROBLEMS IN ACTIVE DISTRIBUTION NETWORKS
Soleimani Bidgoli, Hamid ULg; Glavic, Mevludin ULg; Van Cutsem, Thierry ULg

in Proc. of CIRED Workshop 2014 (in press)

This paper presents a centralized control scheme, inspired of Model Predictive Control (MPC), to manage thermal overloads and correct abnormal voltages in real-time. The control scheme is able to smoothly ... [more ▼]

This paper presents a centralized control scheme, inspired of Model Predictive Control (MPC), to manage thermal overloads and correct abnormal voltages in real-time. The control scheme is able to smoothly bring the system within the desired limits, taking into account its near-future evolution. The control method effectiveness is illustrated on a 20-kV, 32-bus network hosting four distributed generation units. [less ▲]

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See detailLes entreprises publiques locales en Région wallonne (seconde édition)
Durviaux, Ann-Lawrence ULg; Gabriel, Ingrid ULg

Book published by Larcier (in press)

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See detailAlgorithmic and Computational Advances for Fast Power System Dynamic Simulations
Aristidou, Petros ULg; Van Cutsem, Thierry ULg

in Proceedings of the IEEE PES General Meeting (in press)

In this paper, some algorithmic and computational advances are presented for power system dynamic simulations. The heart is a Schur-complement-based solution algorithm, stemming from domain decomposition ... [more ▼]

In this paper, some algorithmic and computational advances are presented for power system dynamic simulations. The heart is a Schur-complement-based solution algorithm, stemming from domain decomposition methods, applied to the differential-algebraic equation model. This algorithm is then accelerated computationally, by employing parallel computing techniques, and numerically, by exploiting time-scale decomposition and localization. Models of a real medium-scale system and a realistic large-scale test system are used for the performance evaluation of the proposed methods. [less ▲]

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See detailOn the convergence of relaxation schemes to couple phasor-mode and electromagnetic transients simulations
Plumier, Frédéric ULg; Geuzaine, Christophe ULg; Van Cutsem, Thierry ULg

in Proceedings of the IEEE PES General Meeting (in press)

Hybrid simulations combining phasor-mode and electromagnetic transients models aim at taking advantage of computational speed of the former and accuracy of the latter. For simulation accuracy, a ... [more ▼]

Hybrid simulations combining phasor-mode and electromagnetic transients models aim at taking advantage of computational speed of the former and accuracy of the latter. For simulation accuracy, a relaxation process is used, which consists of iterating between both models. The convergence properties of this relaxation process are investigated. The speed of convergence is assessed when the variables exchanged at the interface between both models are respectively pure voltage/current sources, Norton/Thévenin equivalents, or a combination of them. Iteratively updated Norton/Thévenin equivalents are shown to drastically reduce the number of relaxation iterations. [less ▲]

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See detailAn online interactive tool to assess energy consumption in residential buildings and for daily mobility
Marique, Anne-Françoise ULg; de Meester, Tatiana; De Herde, André et al

in Energy and Buildings (in press)

Improving energy efficiency in the building and transportation sectors is a viable approach to mitigate the effects of climate change and has become an important policy target. As a result, in addition to ... [more ▼]

Improving energy efficiency in the building and transportation sectors is a viable approach to mitigate the effects of climate change and has become an important policy target. As a result, in addition to scientific research and public policies addressing energy efficiency, raising public awareness of the impact of the behaviour of citizens to energy efficiency is crucial and could quickly lead to significant reductions in the total energy consumption of a territory. In this context, this paper presents a new online interactive tool that enables not only citizens but also local authorities and private developers to (1) assess the sources of energy consumption related to housing and to daily mobility at both the individual and neighbourhood scales, (2) compare these sources and (3) determine relevant and personalised suggestions to reduce energy consumption. Numerous methods and tools, including a typological classification of buildings, thermal dynamic simulations, life-cycle assessments and statistical treatments of national censuses, were used to produce the two large databases used in this interactive tool. This report represents the primary results of a three-year long scientific research project dedicated to the study of energy efficiency in buildings and for daily mobility that is accessible to a large non-specialised audience. [less ▲]

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See detailCapital symbolique
Durand, Pascal ULg

in COnTEXTES : Revue de Sociologie de la Littérature (in press)

Présentation et discussion du concept de « Capital symbolique » dans la sociologie de Pierre Bourdieu.

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See detailFace à la globalisation : de l’interculturalité implicite à l’interculturalité engagée
Defays, Jean-Marc ULg

in Actes du colloque international « Interculturalité : Etat des lieux et perspectives, théories et pratiques », Université Antonine, Beyrouth, Liban, (in press)

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See detailLe français – sur objectifs universitaires – dans les politiques linguistiques et les centres de langues des universités marocaines : état d’une réflexion, esquisse d’un programme
Defays, Jean-Marc ULg; Jaafar, Khalid

in Actes du IIème Forum mondial des Centres Universitaires de Langues – Forum Heracles (Hautes Etudes et Recherches pour les Apprentissages dans les Centres de langues de l’Enseignement Supérieur) (in press)

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See detailLes langues à l’université : changements en cours et à venir
Defays, Jean-Marc ULg

in Actes du Colloque international « Apprendre les langues à l’Université au 21e siècle », DILTEC (Didactique des Langues, des Textes et des Cultures), UPMC, Paris, 9-11 juin 2011 (in press)

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