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See detailFuture preventive therapy: are there promising drug targets
Schoenen, Jean ULg

in Headache Currents (2006), 3

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See detailFuture projections of the Greenland ice sheet climate simulated by the regional climate model MAR forced by 2 CMIP5 global models.
Fettweis, Xavier ULg; Franco, Bruno ULg

Conference (2012, February 14)

As part of the ICE2SEA project, the regional climate model MAR was forced by the global models HadCM3 and ECHAM5 for making future projections of the Greenland Ice Sheet (GrIS) Surface Mass Balance (SMB ... [more ▼]

As part of the ICE2SEA project, the regional climate model MAR was forced by the global models HadCM3 and ECHAM5 for making future projections of the Greenland Ice Sheet (GrIS) Surface Mass Balance (SMB) over 1980-2099 at a resolution of 25km. However, the comparison with MAR forced by the ERA-40 reanalysis over 1980-1999 shows that MAR forced by these GCMs is not able to represent reliably the current SMB due to biases in the general circulation and in the free atmosphere summer temperature modelled by these GCMs around the GrIS. <br /> <br /> That is why, we present here first results of MAR forced by the next generation of GCMs from the CMIP5 data base (CanESM2 and NorESM1 here). The comparison with the ERA-40 forced MAR simulations over current climate is a lot of better, which increases the reliability and the interest of these new MAR projections. In addition, the new scenarios (RCP 2.6, 4.5, 6.0 and 8.5) of the next IPCC Assessment Report (AR5) are used here. These new simulations show notably that the response of SMB to rising temperature is not a linear function of the temperature anomalies due to the positive albedo feedback which accelerates the surface melt. For 2100, in case of extreme rising temperature (RCP 8.5 scenario), MAR simulates a surface GrIS mass loss corresponding to a cumulated sea level rise of about 15 cm since 2000! Mainly the changes in SMB and in surface energy balance will be discussed here. [less ▲]

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See detailFuture projections of the Greenland ice sheet energy balance driving the surface melt
Franco, Bruno ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg

in Cryosphere (The) (2013), 7

In this study, simulations at 25 km resolution are performed over the Greenland ice sheet (GrIS) throughout the 20th and 21st centuries, using the regional climate model MAR forced by four RCP scenarios ... [more ▼]

In this study, simulations at 25 km resolution are performed over the Greenland ice sheet (GrIS) throughout the 20th and 21st centuries, using the regional climate model MAR forced by four RCP scenarios from three CMIP5 global circulation models (GCMs), in order to investigate the projected changes of the surface energy balance (SEB) components driving the surface melt. Analysis of 2000–2100 melt anomalies compared to melt results over 1980–1999 reveals an exponential relationship of the GrIS surface melt rate simulated by MAR to the near-surface air temperature (TAS) anomalies, mainly due to the surface albedo positive feedback associated with the extension of bare ice areas in summer. On the GrIS margins, the future melt anomalies are preferentially driven by stronger sensible heat fluxes, induced by enhanced warm air advection over the ice sheet. Over the central dry snow zone, the surface albedo positive feedback induced by the increase in summer melt exceeds the negative feedback of heavier snowfall for TAS anomalies higher than 4 °C. In addition to the incoming longwave flux increase associated with the atmosphere warming, GCM-forced MAR simulations project an increase of the cloud cover decreasing the ratio of the incoming shortwave versus longwave radiation and dampening the albedo feedback. However, it should be noted that this trend in the cloud cover is contrary to that simulated by ERA-Interim–forced MAR for recent climate conditions, where the observed melt increase since the 1990s seems mainly to be a consequence of more anticyclonic atmospheric conditions. Finally, no significant change is projected in the length of the melt season, which highlights the importance of solar radiation absorbed by the ice sheet surface in the melt SEB. [less ▲]

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See detailFuture projections of the Greenland ice sheet surface mass balance simulated by the regional climate model MAR forced by three CMIP5 global models.
Fettweis, Xavier ULg; Franco, Bruno ULg; Lang, Charlotte ULg et al

Conference (2012, September 11)

As part of the ICE2SEA project, the regional climate model MAR was forced by the global models HadCM3 and ECHAM5 for making future projections of the Greenland Ice Sheet (GrIS) Surface Mass Balance (SMB ... [more ▼]

As part of the ICE2SEA project, the regional climate model MAR was forced by the global models HadCM3 and ECHAM5 for making future projections of the Greenland Ice Sheet (GrIS) Surface Mass Balance (SMB) over 1980-2099 at a resolution of 25km. However, the comparison with MAR forced by the ERA-40 reanalysis over 1980-1999 shows that MAR forced by these GCMs is not able to represent reliably the current SMB due to biases in the general circulation and in the free atmosphere summer temperature modelled by these GCMs around the GrIS. That is why, we present here first results of MAR forced by the next generation of GCMs from the CMIP5 data base (CanESM2, NorESM1 and MIROC5 here). The comparison with the ERA-INTERIM forced MAR simulations over current climate is a lot of better, which increases the reliability and the interest of these new MAR projections. In addition, the new scenarios (RCP 2.6, 4.5, 6.0 and 8.5) of the next IPCC Assessment Report (AR5) are used here. These new simulations show notably that the response of SMB to rising temperature is not a linear function of the temperature anomalies due to the positive albedo feedback which enhances the surface melt. For 2100, in case of extreme rising temperature (RCP 8.5 scenario), MAR simulates a surface GrIS mass loss corresponding to a cumulated sea level rise (SLR) of about 15 cm since 2000! Mainly the changes in SMB and in surface energy balance will be discussed here and estimations of the GrIS surface melt contribution to the SLR using all the CMIP5 outputs will be given. [less ▲]

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See detailThe future sea-level rise contribution of Greenland's glaciers and ice caps
Machguth, H.; Rastner, P.; Bolch, T. et al

in Environmental Research Letters (2013), 8(025005), 14

We calculate the future sea-level rise contribution from the surface mass balance of all of Greenland's glaciers and ice caps (GICs, ~90 000 km2) using a simplified energy balance model which is driven by ... [more ▼]

We calculate the future sea-level rise contribution from the surface mass balance of all of Greenland's glaciers and ice caps (GICs, ~90 000 km2) using a simplified energy balance model which is driven by three future climate scenarios from the regional climate models HIRHAM5, RACMO2 and MAR. Glacier extent and surface elevation are modified during the mass balance model runs according to a glacier retreat parameterization. Mass balance and glacier surface change are both calculated on a 250 m resolution digital elevation model yielding a high level of detail and ensuring that important feedback mechanisms are considered. The mass loss of all GICs by 2098 is calculated to be 2016 ± 129 Gt (HIRHAM5 forcing), 2584 ± 109 Gt (RACMO2) and 3907 ± 108 Gt (MAR). This corresponds to a total contribution to sea-level rise of 5.8 ± 0.4, 7.4 ± 0.3 and 11.2 ± 0.3 mm, respectively. Sensitivity experiments suggest that mass loss could be higher by 20–30% if a strong lowering of the surface albedo were to take place in the future. It is shown that the sea-level rise contribution from the north-easterly regions of Greenland is reduced by increasing precipitation while mass loss in the southern half of Greenland is dominated by steadily decreasing summer mass balances. In addition we observe glaciers in the north-eastern part of Greenland changing their characteristics towards greater activity and mass turnover. [less ▲]

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See detailFuture surface mass balance contribution of the Antarctic ice-sheet to sea level rise
Agosta, Cécile ULg; Fettweis, Xavier ULg; Krinner, Gerhard et al

Scientific conference (2012, December 04)

Most of the IPCC-AR4 global circulation models predict an increase of the Antarctic Surface Mass Balance (SMB) during the 21st century that would mitigate global sea level rise. High-resolution modeling ... [more ▼]

Most of the IPCC-AR4 global circulation models predict an increase of the Antarctic Surface Mass Balance (SMB) during the 21st century that would mitigate global sea level rise. High-resolution modeling is necessary to adequately capture the Antarctic SMB, that is why we present here a downscaling method leading to 15-km SMB resolution for century time-scales over Antarctica. Our first results show that a higher resolution induce at the same time more run-off but a significantly higher mitigation of sea level rise for the next centuries. [less ▲]

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See detailFuture Talks, Compte-rendu du colloque organisé par Die Neue Sammlung, The International Design Museum, les 22 et 23 octobre 2009 à Munich
Defeyt, Catherine ULg

in CeROArt : Conservation, Exposition, Restauration d'Objets d'Art (2010)

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See detailFuture thinking and the self
D'Argembeau, Arnaud ULg

Conference (2011, August 04)

Detailed reference viewed: 39 (4 ULg)
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See detailFuture trends in the management of airway inflammatory disorders
Lekeux, Pierre ULg; Bureau, Fabrice ULg

in Proceedings: 6th Congress of the World Equine Veterinary Association (1999)

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See detailFuturs antérieurs et précédents uchroniques: l'anti-utopie comme conjuration de la menace
Claisse, Frédéric ULg

in Temporalités : Productions, Usages, Figures : Revue de Sciences Sociales et Humaines (2010), (12),

Traditionally regarded as a mere critical inversion of utopia, dystopia will be characterized here as an instance of a more general critical posture, through the concepts of ‘future perfect’ and ... [more ▼]

Traditionally regarded as a mere critical inversion of utopia, dystopia will be characterized here as an instance of a more general critical posture, through the concepts of ‘future perfect’ and ‘counterfactual precedent’. The future perfect belongs to, but differs from the logics of alert in its temporal modalities and use of fiction: the dystopian future is described as having already happened in the actuality of the narrative present, in a paradoxical gesture which aims to conjure up the threat in the recipient’s representational space only to thwart it. The cases examined are taken from the issue of new technologies of surveillance and social control, which challenged stakeholders to update their critical reference points and anticipation skills over the last twenty years. An analysis in terms of the future perfect enables us to understand the swing of configurations: Big Brother is now downgraded as a ‘counterfactual precedent’ compared to the new threats posed by ‘societies of control’. In addition, the similar way these fictional patterns and figures operate points to a cognitive (the articulation between the real and the possible worlds accessed by anticipation) as well as a pragmatic dimension (empowering the political community to envision a new future). By the end of the analysis, fiction appears as both a mode of knowledge and a handle on the world. [less ▲]

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See detailLes futurs enseignants se sentent-ils une responsabilité vis-à-vis de l'échec scolaire ?
Beckers, Jacqueline ULg

in Education et Recherche (1995), 17(3),

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See detailFUV Global View of the Evolution of Electrons and Protons Substorms
Meurant, M.; Hubert, Benoît ULg; Gérard, Jean-Claude ULg et al

Conference (2002, May 01)

The FUV instruments on board the IMAGE satellite provide global images of the N2-LBH (WIC), OI-1356 Ì· (SI13) and Doppler shifted Lyman-alpha (SI12) emissions of the north polar aurora. The 7 Re apogee of ... [more ▼]

The FUV instruments on board the IMAGE satellite provide global images of the N2-LBH (WIC), OI-1356 Ì· (SI13) and Doppler shifted Lyman-alpha (SI12) emissions of the north polar aurora. The 7 Re apogee of the IMAGE orbit allows FUV to simultaneously image the entire auroral zone during a large fraction of the orbit. We present a result of a study of the global morphology evolution during substorm development and recovery. In order to avoid any dayglow contamination, this study is restricted to winter observation. In active regions, electron fluxes and electrons mean energies are deduced assuming a Maxwellian distribution assumption. The mean energy is derived from the WIC/SI13 ratio. Proton fluxes are also determined assuming a 8 keV proton mean energy with a Kappa distribution. The temporal dependence of the electron and proton injections is studied along with their magnetic local time and magnetic latitude variations during several substorms. In particular, the temporal evolution of the magnetic latitude of the bulk proton and electron injections is presented. Our results are found to be consistent with previous studies resting on ground based observations. [less ▲]

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See detailFUV remote sensing of the isotropic boundary and magnetotail stretching
Blockx, Caroline ULg; Gérard, Jean-Claude ULg; Meurant, M. et al

Conference (2004, December 01)

Several studies attempted to identify the Isotropic Boundary (IB) defining the limit between the adiabatic and non-adiabatic trajectories of the trapped protons along closed magnetic field lines. This ... [more ▼]

Several studies attempted to identify the Isotropic Boundary (IB) defining the limit between the adiabatic and non-adiabatic trajectories of the trapped protons along closed magnetic field lines. This boundary is an indicator of the amount of magnetic field lines' stretching in the magnetotail. These studies are based on in situ measurements, resulting in spatially and temporally restricted samples. To avoid this limitation, we propose to use global data obtained with the FUV-SI12 proton imager on board IMAGE spacecraft. We determine at each magnetic local time the position of an optical boundary equivalent to IB and thereby the stretching of the magnetic field lines. We show that the correspondence between the latitude of the maximum proton precipitation observed by SI12 and the IB measured by DMSP satellites is statistically established and depends on the magnetic local time. The relation between the position of the maximum proton precipitation as well as the intensity of this maximum and the magnetic field's distortion is determined by comparison with GOES-8 data. We thus suggest that SI12 can be used as a tool for the global determination of the isotropic boundary and to monitor the amount of stretching in the magnetotail. [less ▲]

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See detailFUV spectroscopy of the H_2 emission in the Jovian aurora: model update and results
Gérard, Jean-Claude ULg; Dols, V.; Colignon, David ULg et al

in Bulletin of the American Astronomical Society (1998, September 01)

The Jovian aurora exhibits bright emissions mainly due the bright Lyman-alpha line and to radiation from excited singlet states to the ground electronic state extending from 800 to 1600 Angstroms. Above ... [more ▼]

The Jovian aurora exhibits bright emissions mainly due the bright Lyman-alpha line and to radiation from excited singlet states to the ground electronic state extending from 800 to 1600 Angstroms. Above 1200 Angstroms, the molecular spectrum is dominated by the Lyman (B-X) bands and continuum and the Werner (C-X) bands. These transitions have been observed with the Goddard High Resolution Spectrometer (GHRS) and the Space Telescope Imaging Spectrometer (STIS) at various spectral and spatial resolutions. To analyze these spectra, a model synthetic auroral spectrum has been constructed and applied to the analysis of the ro-vibrational temperature of H_2 and a search for non-H_2 emission features. It has been recently updated to include the latest singlet state excitation and cascading cross sections, self-absorption in optically thick lines and to account for the energy distribution of the secondary electrons which cause additional excitation. We illustrate these effects in a few study cases and apply the model to high resolution (0.5 Angstroms) GHRS spectra and low resolution STIS spectra of the entire H_2 spectrum at wavelengths longer than Lyman-alpha. We determine the methane column overlying the auroral emission peak and find that a better fit is obtained with additional absorption by acetylene. [less ▲]

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See detailA fuzzy approach to the definition of standardized visibility in fog.
Boreux, Jean-Jacques ULg; Duckstein, Lucien

in Applied Mathematics and Computation (1994), 61(2-3), 287-299

The problem of defining the physical concept of standardized visibility is addressed by means of a fuzzy logic approach. Assuming that several hypotheses hold, it is possible to evaluate a standardized ... [more ▼]

The problem of defining the physical concept of standardized visibility is addressed by means of a fuzzy logic approach. Assuming that several hypotheses hold, it is possible to evaluate a standardized visibility Vk (or meteorological visual range) as the ratio of a psychometric coefficient k and the extinction coefficient σ of the aerosol. The main disadvantage of this relationship due to Koschmieder stems from the fact that the meteorological visual range can be very different from visibility estimated by a human observer with normal sight. This is particularly true during fog extinction coefficient supplied by a transmissometer and the corresponding visibility evaluated by an expert. Calculations are performed according to two different approaches. First, a so-called fuzzy hyperbolic model based on a distance defined by Bardossy et al is presented, yielding a crisp (nonfuzzy) value of the coefficient k. Next, we use the multiplication of two fuzzy numbers, taken as triangular, to build an average fuzzy number k that accounts for the different values found in the literature. The defuzzification of k confirms the result obtained by the first approach. [less ▲]

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See detailFuzzy approximation for convergent model-based reinforcement learning
Busoniu, Lucian; Ernst, Damien ULg; Babuska, Robert et al

in Proceedings of the 2007 IEEE International Conference on Fuzzy Systems (FUZZ-IEEE-07) (2007)

Reinforcement learning (RL) is a learning control paradigm that provides well-understood algorithms with good convergence and consistency properties. Unfortunately, these algorithms require that process ... [more ▼]

Reinforcement learning (RL) is a learning control paradigm that provides well-understood algorithms with good convergence and consistency properties. Unfortunately, these algorithms require that process states and control actions take only discrete values. Approximate solutions using fuzzy representations have been proposed in the literature for the case when the states and possibly the actions are continuous. However, the link between these mainly heuristic solutions and the larger body of work on approximate RL, including convergence results, has not been made explicit. In this paper, we propose a fuzzy approximation structure for the Q-value iteration algorithm, and show that the resulting algorithm is convergent. The proof is based on an extension of previous results in approximate RL. We then propose a modi ed, serial version of the algorithm that is guaranteed to converge at least as fast as the original algorithm. An illustrative simulation example is also provided. [less ▲]

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See detailFuzzy Control Chart A Better Alternative for Shewhart Average Chart
Faraz, Alireza ULg; MOGHADAM, M. B.

in Quality & Quantity (2007), 41(3), 375-385

This paper through a real illustrative example and a power test shows that designing a fuzzy control chart for process average of a continuous (variable) quality characteristic with a warning line is a ... [more ▼]

This paper through a real illustrative example and a power test shows that designing a fuzzy control chart for process average of a continuous (variable) quality characteristic with a warning line is a better alternative to Shewhart ¯X chart in many respects, like providing better neural view to inspectors, offering different strategic options for company to choose, detecting the desire shifts more quickly, and more sensibility to small shifts without any complexity augmentation to the chart. [less ▲]

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See detailFuzzy k-NN applied to moulds detection
Kuske, Martyna; Rubio, R.; Romain, Anne-Claude ULg et al

in Sensors and actuators. B, Chemical (2005), 106(1), 52-60

The possibility to detect Aspergillus versicolor growing on different building materials by a metal oxide sensor array is studied. Results show that an accurate classification rate of 89 +/- 3% can be ... [more ▼]

The possibility to detect Aspergillus versicolor growing on different building materials by a metal oxide sensor array is studied. Results show that an accurate classification rate of 89 +/- 3% can be obtained combining an extended linear discriminant analysis plus a fuzzy k-NN classifier. The classification ability of the classifier is assessed within the dataset by crossvalidation and also in a second dataset collected 5 months later. There is a slight decrease in the classification performance for all the algorithms, being the most sensitive the most accurate one. [less ▲]

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See detailFuzzy K-NN applied to moulds detection
Kuske, Martyna; Rubio, R.; Nicolas, Jacques ULg et al

in Proceedings of ISOEN'03 (2003, June)

The possibility to detect Aspergillus versicolor growing on different building materials by a metal oxide sensor array is studied. Results show that an accurate classification rate of 89 +/- 3% can be ... [more ▼]

The possibility to detect Aspergillus versicolor growing on different building materials by a metal oxide sensor array is studied. Results show that an accurate classification rate of 89 +/- 3% can be obtained combining an extended linear discriminant analysis plus a fuzzy k-NN classifier. The classification ability of the classifier is assessed within the dataset by crossvalidation and also in a second dataset collected 5 months later. There is a slight decrease in the classification performance for all the algorithms, being the most sensitive the most accurate one. [less ▲]

Detailed reference viewed: 21 (4 ULg)