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See detailBGP-aware IGP Link Weight Optimization in Presence of Route Reflectors
Balon, Simon ULg; Leduc, Guy ULg

in IEEE INFOCOM 2009 (2009, April)

The first generation of IGP Link Weight Optimizers (LWOs) was based on presumably invariant intra-domain traffic matrices only, ignoring the fact that updating link weights had a side effect on these ... [more ▼]

The first generation of IGP Link Weight Optimizers (LWOs) was based on presumably invariant intra-domain traffic matrices only, ignoring the fact that updating link weights had a side effect on these traffic matrices due to hot-potato routing, thus result- ing in suboptimal link weight settings, and sometimes to very bad performance. The second generation of IGP LWOs, referred to as BGP-aware LWOs, has been able to optimize link weights while taking hot-potato effects into account. However, these tools relied on the complete visibility assumption fulfilled by e.g. a full-mesh iBGP configu- ration. This paper proposes a third generation LWO, still BGP-aware, but also able to work with iBGP con- figurations based on route reflectors, which usually hide some reachability information from routers. This partial visibility may cause various problems, including path deflections (i.e., the actual egress router is not the expected one), which may in turn create forwarding loops. Our LWO embeds a BGP routing solver which can always predict the actual egress router, even when route reflectors are used. It can also forbid solutions leading to path deflection. Its efficiency is evaluated on a real dataset, and compared to other LWOs. [less ▲]

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See detailTime series of 12CO and 13CO at northern mid-latitudes: Determination of Partial Column and δ13C seasonal and interannual variations
Mahieu, Emmanuel ULg; Duchatelet, Pierre ULg; Rinsland, C. P. et al

in Geophysical Research Abstracts (2009, April), 11(EGU2009-10017-1),

Carbon monoxide (CO) is an important reactive gas in the troposphere. It is emitted at the ground level by fossil fuel combustion and biomass burning. Biogenic sources and oceans as well as oxidation of ... [more ▼]

Carbon monoxide (CO) is an important reactive gas in the troposphere. It is emitted at the ground level by fossil fuel combustion and biomass burning. Biogenic sources and oceans as well as oxidation of methane and nonmethane hydrocarbons complete the emissions budget. Large uncertainties still affect the relative contributions of the identified anthropogenic and natural sources. Destruction by the hydroxyl radical (OH) is the main removal process for CO in both the troposphere and the stratosphere. The resulting average tropospheric lifetime of CO varies from several weeks to a few months. Two approaches have been developed and optimized to independently retrieve abundances of 12CO and 13CO from high-resolution ground-based infrared solar spectra, using sets of carefully selected lines and the SFIT-2 (v3.91) algorithm which implements the optimal estimation method. The corresponding products will be described and characterized in terms of error budget and information content. These strategies have allowed us to produce partial column time series of 12CO and 13CO, using spectra recorded on a regular basis at the Jungfraujoch station (46.5ºN, 8.0ºE, 3580 m asl, Swiss Alps), a site of the Network for the Detection of Atmospheric Composition Change (NDACC). The seasonal and interannual changes observed in the 12CO,13CO and δ13C (13C/12C) data sets will be presented and discussed. Complementary zonal mean time series derived from occultation measurements collected by the ACE-FTS instrument onboard the Canadian SCISAT-1 platform since 2004 will also be included and analyzed, focusing on the upper troposphere-lower stratosphere region of the atmosphere. Finally, we will use GEOS-Chem 3-D chemistry transport model results to help in the interpretation of the short and long-term variations characterizing the ground-based and satellite data sets, focusing on the factors influencing the partitioning between the two CO isotopologues. [less ▲]

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See detailGreenland ice sheet projections from IPCC AR4 global models
Franco, Bruno ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg et al

Poster (2009, April)

The atmosphere-ocean general circulation models (AOGCMs) used for the IPCC 4th Assessment Report (IPCC AR4) are evaluated for the Greenland ice sheet (GrIS) current climate modelling. The most efficient ... [more ▼]

The atmosphere-ocean general circulation models (AOGCMs) used for the IPCC 4th Assessment Report (IPCC AR4) are evaluated for the Greenland ice sheet (GrIS) current climate modelling. The most efficient AOGCMs are chosen by comparison between the 1970-1999 outputs of the Climate of the twentieth Century experiment (20C3M) and reanalyses (ECMWF, NCEP/NCAR). This comparison reveals that surface parameters such as temperature and precipitation are highly correlated to the atmospheric circulation (500 hPa geopotential height) and its interannual variability (North Atlantic oscillation). The outputs of the three most efficient AOGCMs are then used to assess the changes planned by three IPCC greenhouse gas emissions scenarios (SRES) for the 2070-2099 period. Future atmospheric circulation changes should dampen the west-to-east circulation (zonal flow) and should enhance the Meridional Overturning Circulation (MOC). As a consequence, this provides more heat and moisture to the GrIS, increasing temperature on the whole ice sheet and precipitation on the north-eastern region. It is also shown that the GrIS surface mass balance (SMB) anomalies from the SRES A1B scenario are about -300 km³/yr with respect to the 1970-1999 period, leading to 5 cm of global sea-level rise (SLR) for the end of the 21st century. This work helps to choose the boundaries conditions for AOGCMs downscaled future projections. [less ▲]

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See detailMieux Traiter le diabète permet-il de vivre plus longtemps?
Scheen, André ULg; Philips, Jean-Christophe ULg

in Médecine Clinique Endocrinologie & Diabète (2009), hors série(avril 2009), 2-7

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See detailCombinaison fixe perindopril-amlodipine (Coveram®) dans le traitement de l'hypertension artérielle et de l'insuffisance coronaire.
Scheen, André ULg; Krzesinski, Jean-Marie ULg

in Revue Médicale de Liège (2009), 64(4), 223-227

Coveram® is a new fixed combination of an angiotensin converting enzyme inhibitor, perindopril, and a calcium antagonist, amlodipine. This new medication is indicated for the treatment of arterial ... [more ▼]

Coveram® is a new fixed combination of an angiotensin converting enzyme inhibitor, perindopril, and a calcium antagonist, amlodipine. This new medication is indicated for the treatment of arterial hypertension and/or stable coronary heart disease. Such fixed combination of two molecules that have been extensively evaluated according to evidence-based medicine offers the advantage of an excellent efficacy, associated with a good tolerance profile, and favours patient’s compliance. The marketing of different formulations of Coveram® combining various dosages allows easy adjustment and titration of each of the components according to the individual patient’s characteristics. [less ▲]

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See detailLayer-by-layer self-assembled chitosan coating on electrospun nanofibers
Croisier, Florence ULg; Aqil, Abdelhafid ULg; Detrembleur, Christophe ULg et al

Poster (2009, April)

By combining electrospinning technique and layer-by-layer deposition, we produced a new material made of multilayered, chitosan-based nanofibers. Layer-by-layer (LBL) is a well-known method for surface ... [more ▼]

By combining electrospinning technique and layer-by-layer deposition, we produced a new material made of multilayered, chitosan-based nanofibers. Layer-by-layer (LBL) is a well-known method for surface coating, based on electrostatic interactions. It enables the controllable deposition of a variety of polyions including synthetic and natural materials, with designable layer structure, defined wall thickness and size. Electrospinning (ESP) technique allows the fabrication of polymer fibers ranging from nanometers to a few microns in diameter, depending on the polymer characteristics (a.o. molecular weight, solution viscosity and conductivity) and processing conditions (electric potential, distance between syringe-capillary and collection plate, concentration, flow rate). Mats of nanofibers produced by ESP display a very large surface area-to-volume ratio and high porosity with very small pore size. The nanometric scale of electrospun fibers also proves a positive effect on cellular growth, as fibers mats mimic extracellular matrix structure. The association of these two techniques with the use of biocompatible and biodegradable polymers such as chitosan, gives outstanding prospects in the field of biomedical applications, especially for the preparation of wound dressings, artificial skin or tissue engineering scaffolds. In the present study, a charged copolymer, poly(methylmethacrylate-block-methacrylic acid), was added to a poly(ε-caprolactone) or poly(D,L-lactide) solution before electrospinning in order to obtain charges on fibers surface. Oppositely charged polyelectrolytes – chitosan and poly(styrene sulfonate) or hyaluronic acid – were then alternately deposited on these aliphatic polyester fiber “cores” using LBL method. The aliphatic polyester core was also removed selectively to confirm the existence of a multilayered shell, obtaining hollow fibers. [less ▲]

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See detailCycles in the Temperature Data Are Induced by the Sun
Nicolay, Samuel ULg; Mabille, Georges ULg; Fettweis, Xavier ULg et al

Poster (2009, April)

The presence of two cycles of period of 30 and 42 months approximatively has been observed in temperature records and climatic indices. Moreover, it has been shown that these cycles are statistically ... [more ▼]

The presence of two cycles of period of 30 and 42 months approximatively has been observed in temperature records and climatic indices. Moreover, it has been shown that these cycles are statistically significant. Here we outline the role played by the Sun in the presence of these cycles, observed in time series. To do so, we use IPCC AR4 climatic models, sunspot number data and the Morlet wavelet method. [less ▲]

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See detailConfidence Levels for the Cycles Found in Air Temperature Data
Mabille, Georges ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg et al

Poster (2009, April)

Recently, new cycles have been observed in air temperature data and proxy series using a wavelet-based methodology. Although many evidences attest the validity of this method applied to climatic data, no ... [more ▼]

Recently, new cycles have been observed in air temperature data and proxy series using a wavelet-based methodology. Although many evidences attest the validity of this method applied to climatic data, no systematic study of its efficiency has been carried out. Here, we estimate the confidence levels for this approach and show that the observed cycles are significant. [less ▲]

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See detailTechnological and Economical Survey of Organic Rankine Cycle Systems
Quoilin, Sylvain ULg; Lemort, Vincent ULg

(2009, April)

This paper presents an overview of current R&D in the field of small and middle scale Organic Rankine Cycles (ORC’s). Major ORC’s applications are described and their technical and economical maturity is ... [more ▼]

This paper presents an overview of current R&D in the field of small and middle scale Organic Rankine Cycles (ORC’s). Major ORC’s applications are described and their technical and economical maturity is analyzed. The paper also emphasizes the selection criteria for the expander and for the working fluid. [less ▲]

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See detailDissuasion nucléaire et Europe. Entre zones grises et zones floues
Dumoulin, André ULg

in Défense et sécurité internationale (2009)

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See detailL'évaluation actuarielle des engagements de pension selon l'IAS 19 et ses perspectives d'évolution
Sougné, Danielle ULg

in Revue française de comptabilité (2009)

Detailed reference viewed: 65 (7 ULg)
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See detailTechnology for a Mid-IR Flagship Mission to Characterize Earth-like Exoplanets
Lawson, P. R.; Absil, Olivier ULg; Akeson, R. L. et al

E-print/Working paper (2009)

The exploration of Earth-like exoplanets will be enabled at mid-infrared wavelengths through technology and engineering advances in nulling interferometry and precision formation flying. Nulling ... [more ▼]

The exploration of Earth-like exoplanets will be enabled at mid-infrared wavelengths through technology and engineering advances in nulling interferometry and precision formation flying. Nulling interferometry provides the dynamic range needed for the detection of biomarkers. Formation flying provides the angular resolution required in the mid-infrared to separately distinguish the spectra of planets in multi-planet systems. The flight performance requirements for nulling have been met and must now be validated in a flight-like environment. Formation-flying algorithms have been demonstrated in the lab and must now be validated in space. Our proposed technology program is described. [less ▲]

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See detailExoplanet Characterization and the Search for Life
Kasting, James; Traub, W.; Roberge, A. et al

E-print/Working paper (2009)

Over 300 extrasolar planets (exoplanets) have been detected orbiting nearby stars. We now hope to conduct a census of all planets around nearby stars and to characterize their atmospheres and surfaces ... [more ▼]

Over 300 extrasolar planets (exoplanets) have been detected orbiting nearby stars. We now hope to conduct a census of all planets around nearby stars and to characterize their atmospheres and surfaces with spectroscopy. Rocky planets within their star's habitable zones have the highest priority, as these have the potential to harbor life. Our science goal is to find and characterize all nearby exoplanets; this requires that we measure the mass, orbit, and spectroscopic signature of each one at visible and infrared wavelengths. The techniques for doing this are at hand today. Within the decade we could answer long-standing questions about the evolution and nature of other planetary systems, and we could search for clues as to whether life exists elsewhere in our galactic neighborhood. [less ▲]

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See detailAre bio and nano likely to be compared? If so, what are the consequences on public participation?
Thoreau, François ULg

Conference (2009, March 29)

Like modern biotechnologies, nanotechnologies are a generic area of research linked with several interconnected disciplinary fields. They may be converted into a large panel of applications. It also ... [more ▼]

Like modern biotechnologies, nanotechnologies are a generic area of research linked with several interconnected disciplinary fields. They may be converted into a large panel of applications. It also brings, with its development, promises of a quite huge potential including important economic opportunities. Both of those emergent technologies also raise important social, ethical or environmental issues. Nevertheless, many substantive differences remain between biotechnologies and nanotechnologies. The former was introduced in society by a time public actors were less sensitive to public participation, as shows the history of parliamentary Technology Assessment. A lack of public participation is often told to have grounded some public opposition to some particular biotechnologies, with the usually quoted case of GMOs. The latter are currently under development in quite other circumstances, as social shaping of technology begins to be widely acknowledged and role played by STS community grows faster. Nanotechnologies deal with more uncertainties and more complexity. So it is commonly accepted that, within their development process, they should include more public participation to avoid some pitfalls of biotechnologies. Still, other differences that context exist between biotechnologies and nanotechnologies. It may be stressed that biotechnologies have left laboratories for a private financial designing of marketable products and that nanotechnologies are just starting to leave laboratories under great public impulsions, with wide public support and funding, as in the case of the National Nanotechnology Initiative in the US. So in the presentation we consider whether, given those differences, biotechnologies and nanotechnologies are likely to be compared. Then we pick a look to potential consequences related to public participation. Should there be more public participation? What for? Should it be driven in a different way? [less ▲]

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See detailInter and intra genetic biodiversity in South East asian rodents: new insights for their conservation
Pagès, Marie ULg; Latinne, Alice ULg; Rivière, Taiana et al

Conference (2009, March 28)

Detailed reference viewed: 13 (1 ULg)