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See detailMulti wavelength study of the gravitational lens system RXS J1131-1231 - II. Lens model and source reconstruction
Claeskens, Jean-François ULg; Sluse, Dominique ULg; Riaud, Pierre ULg et al

in Astronomy and Astrophysics (2006), 451(3), 865-879

Aims. High angular resolution images of the complex gravitational lens system RXS J1131-1231 (a quadruply imaged AGN with a bright Einstein ring) obtained with the Advanced Camera for Surveys and NICMOS ... [more ▼]

Aims. High angular resolution images of the complex gravitational lens system RXS J1131-1231 (a quadruply imaged AGN with a bright Einstein ring) obtained with the Advanced Camera for Surveys and NICMOS instruments onboard the Hubble Space Telescope are analysed to determine the lens model and to reconstruct the host galaxy. Methods. The lens model is constrained by the relative astrometric positions of the lens and point-like images, and by the extended lensed structures. The non-parametric light distribution is recovered in the source plane by means of back ray-tracing. Results. 1-Precise astrometry and photometry of the four QSO lensed images (A-D) and of the lensing galaxy ( G) are obtained. They are found in agreement with an independent study presented in a companion paper. The position and colours of the X object seen in projection close to the lens are found to be only compatible with a satellite galaxy associated with the lens. 2- The Singular Isothermal Ellipsoid plus external shear provides a good fit of the astrometry of images A-D. The positions of extended substructures are also well reproduced. However an octupole ( m = 4) must be added to the lens potential in order to reproduce the observed lens position, as well as the I-B/I-C point-like image flux ratio. The ellipticity and orientation of the mass quadrupole are found similar to those of the light distribution, fitted by a Sersic profile. The lens (z = 0.295) is found to be a massive elliptical in a rich environment and showing possible evolution with respect to z = 0. 3- The host galaxy ( z = 0.658) is found to be a substantially magnified ( M similar to 9) luminous Seyfert 1 spiral galaxy. The angular resolution is sufficient to see regions where stars are intensively forming. Interaction with a closeby companion is also observed. 4- Finally, in the case of RXS J1131-1231, extended lensed structures do not help much in constraining the lens model. [less ▲]

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See detailMulti- Channel Service Management: How well Integrated are the Channels?
Liljander, V.; Pihlstrom, M.; Van Riel, Allard ULg

Poster (2008, July 14)

Detailed reference viewed: 27 (2 ULg)
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See detailMulti- Sensor 3D Image Fusion and Interactive Search
Ross, William; Waxman, Allen M.; Streilein, William et al

Conference (2000, July)

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See detailMulti- sensor Image Fusion for Efficient Color 3D Site Visualization and Rapid Analysis Utilizing Search Acceleration Algorithms
Ross, William; Waxman, Allen M.; Streilein, William et al

Conference (2000, May)

Detailed reference viewed: 6 (1 ULg)
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See detailMulti-affine analysis of typical currency exchange rates
Vandewalle, Nicolas ULg; Ausloos, Marcel ULg

in European Physical Journal B -- Condensed Matter (1998), 4(2), 257-261

For foreign currency exchange rates; multi-affine analysis can put quantitatively into evidence the differences between correlated (daily closing market) values and random walks in time dependent data ... [more ▼]

For foreign currency exchange rates; multi-affine analysis can put quantitatively into evidence the differences between correlated (daily closing market) values and random walks in time dependent data. The H(q) spectrum is presented and discussed here for the USD/DEM and JPY/USD exchange rates. The time-evolution of these ratios is found to be multi-affine. The h(gamma)-curve describing the hierarchy of exponents is numerically obtained. Our findings suggest that the modelling of exchange rate time-evolution from day to day is possible within the framework of modern statistical physics and related to models of turbulence in the physics of fluids. Finally, we argue that there is a multiplicity of information levels in the foreign exchange market such that the "efficient market theory" is a crude oversimplification indeed. [less ▲]

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See detailA multi-Agent System for Architectural Sketches Interpretation
Juchmes, Roland ULg; Leclercq, Pierre ULg; Azar, Sleiman

in Hugues, John F.; Jorge, Joaquim A. (Eds.) Eurographics Workshop on Sketch-Based Interfaces and Modeling (2004)

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See detailMulti-allergens detection by flow cytometric immunoassay
Otto; Planque; Lamote et al

Poster (2015, November)

Detailed reference viewed: 26 (4 ULg)
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See detailMulti-Aperture Imaging of Extrasolar Planetary Systems
Absil, Olivier ULg

in Coudé du Foresto, Vincent; Gelino, Dawn; Ribas, Ignasi (Eds.) Pathways Towards Habitable Planets (2010, October 01)

In this paper, we review the various ways in which an infrared stellar interferometer can be used to perform direct detection of extrasolar planetary systems. We first review the techniques based on ... [more ▼]

In this paper, we review the various ways in which an infrared stellar interferometer can be used to perform direct detection of extrasolar planetary systems. We first review the techniques based on classical stellar interferometry, where (complex) visibilities are measured, and then describe how higher dynamic ranges can be achieved with nulling interferometry. The application of nulling interferometry to the study of exozodiacal discs and extrasolar planets is then discussed and illustrated with a few examples. [less ▲]

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See detailMulti-aperture imaging of extrasolar planetary systems (invited review)
Absil, Olivier ULg

Scientific conference (2009, September 14)

Space‐based nulling interferometry has been identified since 1978 as a promising technique to detect and characterize extrasolar Earth‐like planets. In this talk, I will review the evolution of the ... [more ▼]

Space‐based nulling interferometry has been identified since 1978 as a promising technique to detect and characterize extrasolar Earth‐like planets. In this talk, I will review the evolution of the multi‐aperture concepts dedicated to Earth‐like planet imaging during the last 30 years, and discuss the future prospects in this field. In particular, I will describe the proposed architecture for the Darwin/TPF‐I mission, which has resulted from a common optimization effort by ESA and NASA and from various industrial studies during the past decade. The main scientific and technical hard points will be critically discussed. This talk will also review the precursor instruments (present and future) that could enable future flagship interferometric missions similar to Darwin/TPF‐I. [less ▲]

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See detailA multi-approach survey as the most reliable tool to accurately assess biodiversity: the example of Thai murine rodents
Chaval, Yannick; Dobigny, Gauthier; Michaux, Johan ULg et al

in Kasetsart Journal. Natural Sciences (2010), 44(4), 590-603

Wildlife surveys rely on an accurate taxonomic framework. Identification tools used to reach this goal are not equivalent and may depend on several objectives and constraints, including sampling ... [more ▼]

Wildlife surveys rely on an accurate taxonomic framework. Identification tools used to reach this goal are not equivalent and may depend on several objectives and constraints, including sampling conservation difficulties, the invasiveness of the sampling techniques, sampling capacity, the relevance of the results, materials needed, the cost and the user time required in the field and laboratory. This article presents and discusses the advantages and limits of each identification tool used in the Ceropath (Community ecology of rodents and their pathogens in South East Asia) program to reach a fast and relevant identification of the rodents sampled. It is concluded that there needs to be a combination of the results from different methods, including the most recent ones, to achieve an improvement in taxonomic identification. [less ▲]

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See detailMulti-area security assessment: results using efficient bounding method
Wehenkel, Louis ULg; Glavic, Mevludin; Ernst, Damien ULg

in Proceedings of the 38th North American Power Symposium (NAPS 2006) (2006)

We present our recent results on using previously introduced framework for multi-area security assessment in large interconnections. The basic idea of the framework is exchanging just enough information ... [more ▼]

We present our recent results on using previously introduced framework for multi-area security assessment in large interconnections. The basic idea of the framework is exchanging just enough information so that each operator can evaluate the impact in his control area of contingencies both internal and external to his area. We provide illustrations based on a localization concept known as efficient bounding method and recently introduced approximate DC model of the European interconnected system. In this paper we focus on four transmission system operators (within the approximate DC model): Belgium, France, Germany, and Netherlands (for both Summer and Winter-peak load conditions). [less ▲]

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See detailMulti-armed bandit based policies for cognitive radio's decision making issues
Jouini, Wassim; Ernst, Damien ULg; Moy, Christophe et al

in Proceedings of the 3rd International Conference on Signals, Circuits and Systems (SCS) (2009, November)

We suggest in this paper that many problems related to Cognitive Radio’s (CR) decision making inside CR equipments can be formalized as Multi-Armed Bandit problems and that solving such problems by using ... [more ▼]

We suggest in this paper that many problems related to Cognitive Radio’s (CR) decision making inside CR equipments can be formalized as Multi-Armed Bandit problems and that solving such problems by using Upper Confidence Bound (UCB) algorithms can lead to high-performance CR devices. An application of these algorithms to an academic Cognitive Radio problem is reported. [less ▲]

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See detailMulti-aspects architectural design: the conception of new building envelopes
Dupagne, Albert ULg; Hauglustaine, Jean-Marie ULg

Conference (1999, October)

The building is not a unique object any more, but results from the assembly of components, among which the envelope is one of the objects assembled. The components are more and more specialised and ... [more ▼]

The building is not a unique object any more, but results from the assembly of components, among which the envelope is one of the objects assembled. The components are more and more specialised and acquire an actual independence. On the other hand, the components of the building and of the envelope have a large diversity of life cycles; moreover the life duration of the components shortens, because they rapidly become obsolescent from many points of view: technology, technique, performance, functionality, etc., so that their easy transformability, adaptability (and/or removability) becomes an important quality required to them. The conception of new building envelopes must take these aspects into account, in order to obtain a best practice design. [less ▲]

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See detailMulti-axial integrated optics solution for POPS, a 2nd-generation VLTI fringe tracker
Tarmoul, Nassima; Hénault, François; Mourard, Denis et al

in Danchi, W. C.; Delplancke, F.; Rajagopal, J. K. (Eds.) Optical and Infrared Interferometry II (2010, July)

POPS (Planar Optical Phase Sensor) is a second-generation fringe tracker for the Very Large Telescope Interferometer (VLTI), intended to simultaneously measure the cophasing and coherencing errors of up ... [more ▼]

POPS (Planar Optical Phase Sensor) is a second-generation fringe tracker for the Very Large Telescope Interferometer (VLTI), intended to simultaneously measure the cophasing and coherencing errors of up to six Unit Telescopes (UT) or Auxiliary Telescopes (AT) in real time. The most promising concepts are probably based on the utilization of Integrated Optics (IO) components, and were the scope of a Phase A study led by Observatoire de Grenoble (LAOG). Herein is described a tentative design built around a multi-axial IO chip whose fringes are dispersed downstream on a detector array, and a Chromatic Phase Diversity algorithm presented in another paper of this conference . We depict the foreseen opto-mechanical, detection and software implementations, and provide numerical results from a realistic simulation model in terms of group and phase delay measurement accuracy and limiting magnitudes in the K band. The ultimate performance of the method is discussed and compared with the original 2[SUP]nd[/SUP] generation VLTI fringe tracker requirements. [less ▲]

Detailed reference viewed: 51 (1 ULg)
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See detailMulti-biomaterial for controlled release of active substances
Zalfen, Alina; Nizet, Dominique; Jérôme, Christine ULg et al

Poster (2006)

Detailed reference viewed: 15 (0 ULg)
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See detailMulti-Camera People Tracking by Collaborative Particle Filters and Principal Axis-Based Integration
Du, Wei ULg; Piater, Justus ULg

in Asian Conference on Computer Vision (2007)

Detailed reference viewed: 21 (0 ULg)
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See detailA multi-centre clinico-genetic analysis of the VPS35 gene in Parkinson disease indicates reduced penetrance for disease-associated variants.
Sharma, Manu; Ioannidis, John P. A.; Aasly, Jan O. et al

in Journal of Medical Genetics (2012), 49(11), 721-6

BACKGROUND: Two recent studies identified a mutation (p.Asp620Asn) in the vacuolar protein sorting 35 gene as a cause for an autosomal dominant form of Parkinson disease . Although additional missense ... [more ▼]

BACKGROUND: Two recent studies identified a mutation (p.Asp620Asn) in the vacuolar protein sorting 35 gene as a cause for an autosomal dominant form of Parkinson disease . Although additional missense variants were described, their pathogenic role yet remains inconclusive. METHODS AND RESULTS: We performed the largest multi-center study to ascertain the frequency and pathogenicity of the reported vacuolar protein sorting 35 gene variants in more than 15,000 individuals worldwide. p.Asp620Asn was detected in 5 familial and 2 sporadic PD cases and not in healthy controls, p.Leu774Met in 6 cases and 1 control, p.Gly51Ser in 3 cases and 2 controls. Overall analyses did not reveal any significant increased risk for p.Leu774Met and p.Gly51Ser in our cohort. CONCLUSIONS: Our study apart from identifying the p.Asp620Asn variant in familial cases also identified it in idiopathic Parkinson disease cases, and thus provides genetic evidence for a role of p.Asp620Asn in Parkinson disease in different populations worldwide. [less ▲]

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See detailMulti-Chromatic Analysis of SAR Images for Coherent Target Detection
Bovenga, Fabio; Barbier, Christian ULg; De Rauw, Dominique ULg et al

in Remote Sensing (2014), 6

This work investigates the possibility of performing target analysis through the Multi-Chromatic Analysis (MCA), a technique that basically explores the information content of sub-band images obtained by ... [more ▼]

This work investigates the possibility of performing target analysis through the Multi-Chromatic Analysis (MCA), a technique that basically explores the information content of sub-band images obtained by processing portions of the range spectrum of a synthetic aperture radar (SAR) image. According to the behavior of the SAR signal at the different sub-bands, MCA allows target classification. Two strategies have been experimented by processing TerraSAR-X images acquired over the Venice Lagoon, Italy: one exploiting the phase of interferometric sub-band pairs, the other using the spectral coherence derived by computing the coherence between sub-band images of a single SAR acquisition. The first approach introduces the concept of frequency-persistent scatterers (FPS), which is complementary to that of the time-persistent scatterers (PS). FPS and PS populations have been derived and analyzed to evaluate the respective characteristics and the physical nature of the targets. Spectral coherence analysis has been applied to vessel detection, according to the property that, in presence of a random distribution of surface scatterers, as for open sea surfaces, spectral coherence is expected to be proportional to sub-band intersection, while in presence of manmade structures it is preserved anyhow. First results show that spectral coherence is well preserved even for very small vessels, and can be used as a complementary information channel to constrain vessel detection in addition to classical Constant False Alarm Rate techniques based on the sole intensity channel. [less ▲]

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See detailMulti-Cité, une expérience de formation initiale inédite
Beckers, Jacqueline ULg; Stegen, Pierre; Merenne-Schoumaker, Bernadette ULg et al

in Puzzle (1997), 2(juin), 10-16

L'article présente l'expérience de formation co-jointe de futurs professeurs de géographie de l'ULg et de la Haute Ecole Charlemagne via la réalisation d'un jeu pédagogique portant sur la gestion urbaine ... [more ▼]

L'article présente l'expérience de formation co-jointe de futurs professeurs de géographie de l'ULg et de la Haute Ecole Charlemagne via la réalisation d'un jeu pédagogique portant sur la gestion urbaine, jeu publié dans GEO 41. [less ▲]

Detailed reference viewed: 36 (12 ULg)
See detailMulti-city network on drug mesure trends
Honore, A.; Amraei, M.; Bils, L. et al

Report (1999)

Detailed reference viewed: 7 (0 ULg)