Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
See detailLarge displacement formulations for elastic bodies
Fraeijs de Veubeke, Baudouin ULiege

Report (1969)

Detailed reference viewed: 21 (0 ULiège)
Full Text
See detailLarge Dynamic Range Co-Phasing System Development for Segmented Telescope Mirrors
Simar, Juan Felipe ULiege

Poster (2011, December 02)

Detailed reference viewed: 72 (23 ULiège)
Full Text
Peer Reviewed
See detailLarge earthquakes Cycles in Lake Sediments along the North Anatolian Fault, Turkey
Boës, X.; Moran, S. B.; King, J. et al

in Journal of Paleolimnology (2009), (10.1007/s10933-009-9376-x),

In 1999, the large surface-rupturing earth- quakes of Izmit and Duzce completed a 60-year cycle that included a westward migration of nine consecutive large earthquake failures ([50 km surface rupture ... [more ▼]

In 1999, the large surface-rupturing earth- quakes of Izmit and Duzce completed a 60-year cycle that included a westward migration of nine consecutive large earthquake failures ([50 km surface rupture), which started with the 1939 Erzincan earthquake in eastern Turkey. In this study, we focused on seismic cycles and seismic risk predictability along the North Anatolian Fault (NAF). Toward the west end of the NAF (26°E–32°E, i.e. Bolu), large earthquake fre- quency is measured from either historic earthquake catalogs, or geologic records from isolated outcrops and marine sediment cores from the Marmara Sea. In comparison, the eastern part of the NAF zone (32°E– 42°E) is less well documented by palaeo-seismologic archives. Thus, the sediment records of lake basins located on the eastern NAF zone constitute a unique opportunity for testing a new palaeo-seismologic approach. To this end, we used a diverse array of complementary methods involving: (1) a 600-km transect of fault-related lakes, (2) sedimentologic observations on cores from six lakes, and (3) a comparison between records of catastrophic sediment transfers in lakes (i.e. radionuclide chronomarkers and erosion tracers) and historic earthquake reports. Our study indicates that lakes along the NAF are sensitive geologic recorders of large surface-rupturing earth- quakes (surface-wave magnitude (Ms) C 6.9); smaller intensities are not recorded. The most responsive lake systems exhibit increases in sediment accumulation by a factor of [40 for a [3-m strike-slip displacement (Ms C 7). However, based on results from the 1939 Erzincan earthquake (Ms = 7.8) chronostratigraphic marker, large surface-rupturing earthquakes are detected only by certain lake records and not by others. Matching multiple lake records along the NAF pro- vides information both on the location of a surface rupture of a paleo-earthquake as well as its magnitude. Finally, the shallow lake basins along the NAF could potentially document cycles of large seismic events for at least the late Holocene. [less ▲]

Detailed reference viewed: 58 (5 ULiège)
Full Text
Peer Reviewed
See detailLarge elasto-optic effect and reversible electrochromism in multiferroic BiFeO3
Sando, D.; Yang, Yurong; Bousquet, Eric ULiege et al

in Nature Communications (2016), 7

The control of optical fields is usually achieved through the electro-optic or acousto-optic effect in single-crystal ferroelectric or polar compounds such as LiNbO3 or quartz. In recent years, tremendous ... [more ▼]

The control of optical fields is usually achieved through the electro-optic or acousto-optic effect in single-crystal ferroelectric or polar compounds such as LiNbO3 or quartz. In recent years, tremendous progress has been made in ferroelectric oxide thin film technology—a field which is now a strong driving force in areas such as electronics, spintronics and photovoltaics. Here, we apply epitaxial strain engineering to tune the optical response of BiFeO3 thin films, and find a very large variation of the optical index with strain, corresponding to an effective elasto-optic coefficient larger than that of quartz. We observe a concomitant strain-driven variation in light absorption—reminiscent of piezochromism—which we show can be manipulated by an electric field. This constitutes an electrochromic effect that is reversible, remanent and not driven by defects. These findings broaden the potential of multiferroics towards photonics and thin film acousto-optic devices, and suggest exciting device opportunities arising from the coupling of ferroic, piezoelectric and optical responses. [less ▲]

Detailed reference viewed: 28 (8 ULiège)
Full Text
Peer Reviewed
See detailLarge Excess of Heavy Nitrogen in Both Hydrogen Cyanide and Cyanogen from Comet 17P/Holmes
Bockelée-Morvan, D.; Biver, N.; Jehin, Emmanuel ULiege et al

in Astrophysical Journal (2008), 679(Letters), 49-52

From millimeter and optical observations of the Jupiter-family comet 17P/Holmes performed soon after its huge outburst of 2007 October 24, we derive [SUP]14[/SUP]N/[SUP]15[/SUP]N = 139 +/- 26 in HCN and ... [more ▼]

From millimeter and optical observations of the Jupiter-family comet 17P/Holmes performed soon after its huge outburst of 2007 October 24, we derive [SUP]14[/SUP]N/[SUP]15[/SUP]N = 139 +/- 26 in HCN and [SUP]14[/SUP]N/[SUP]15[/SUP]N = 165 +/- 40 in CN, establishing that HCN has the same nonterrestrial isotopic composition as CN. The same conclusion is obtained for the long-period comet C/1995 O1 (Hale-Bopp) after a reanalysis of previously published measurements. These results are compatible with HCN being the prime parent of CN in cometary atmospheres. The [SUP]15[/SUP]N excess relative to the Earth's atmospheric value indicates that N-bearing volatiles in the solar nebula underwent important N isotopic fractionation at some stage of solar system formation. HCN molecules never isotopically equilibrated with the main nitrogen reservoir in the solar nebula before being incorporated in Oort Cloud and Kuiper Belt comets. The [SUP]12[/SUP]C/[SUP]13[/SUP]C ratios in HCN and CN are measured to be consistent with the terrestrial value. [less ▲]

Detailed reference viewed: 45 (5 ULiège)
See detailLarge group teaching: the distance learning solution?
Pasleau, Françoise ULiege; Doseray, Patrick; Fairon, Nicolas ULiege et al

Poster (2005, June)

Problem-based learning has been introduced at the University of Liège for four years now. The medical library was committed with the organisation of different activities (60 hours/2 years), starting with ... [more ▼]

Problem-based learning has been introduced at the University of Liège for four years now. The medical library was committed with the organisation of different activities (60 hours/2 years), starting with the control of basic computer litteracy, continuing with an analysis of the structure of the different document types used for scientific communication as well as the discovery of both traditional and electronic medical libraries, to end with guidelines for information retrieval. Such courses requested new approaches and several difficulties had to be taken into consideration including : 1. The transfer of skills rather than kowledge. Some theoretical bases have to be taught before practicing. But the students mostly need to be challenged with different situations requesting different approaches of litterature searching. 2. The course is given before the students feel the need of it. The librarians enconter the students during the first semester of the second year before the students are asked to search the medical litterature to build their own knowledge about clinical matters. 3. The absence of motivation. Second year medical students are focused on major courses in basic and preclinical sciences. 4. Large group teaching (n ≥ 300). All the sections of the medical Faculty are concerned. 5. Inadequate logistic support. Small sized computer rooms do not allow the organization of very many parallel hand-on sessions. 6. Insufficient teaching staffs. Distance learning tools were used to develope online activities complementary to face to face teaching. They are focused on practice. Links to the theory are provided but only when they are indispensable. Many quizzes are also proposed in order to trigger critical mind and auto-evaluation. By January 2005, a first cycle will be completed from the beginning of the course to the final examination. We plan to survey students from every section in order to evaluate the impact of this new teaching strategy. Their observations will be reported as well as our conclusions and suggestions for possible improvements. [less ▲]

Detailed reference viewed: 90 (5 ULiège)
Full Text
Peer Reviewed
See detailLarge Margin Classification with the Progressive Hedging Algorithm
Defourny, Boris ULiege; Wehenkel, Louis ULiege

Conference (2009, December)

Several learning algorithms in classification and structured prediction are formulated as large scale optimization problems. We show that a generic iterative reformulation and resolving strategy based on ... [more ▼]

Several learning algorithms in classification and structured prediction are formulated as large scale optimization problems. We show that a generic iterative reformulation and resolving strategy based on the progressive hedging algorithm from stochastic programming results in a highly parallel algorithm when applied to the large margin classification problem with nonlinear kernels. We also underline promising aspects of the available analysis of progressive hedging strategies. [less ▲]

Detailed reference viewed: 62 (2 ULiège)
Full Text
Peer Reviewed
See detailLarge N(c) QCD versus quark model
Semay, Claude; Buisseret, Fabien; Stancu, Floarea ULiege et al

in Few-Body Systems (2008), 44

Detailed reference viewed: 22 (2 ULiège)
Full Text
See detailLarge Nc baryons and Regge trajectories
Matagne, Nicolas; Stancu, Floarea ULiege

in Bled Workshops in Physics (2013, November), 14(1), 37-42

The mixed symmetric positive and negative parity baryons are described in a similar way in the $1/N_c$ expansion method of QCD by using a procedure where the permutation symmetry is incorporated exactly ... [more ▼]

The mixed symmetric positive and negative parity baryons are described in a similar way in the $1/N_c$ expansion method of QCD by using a procedure where the permutation symmetry is incorporated exactly. This allows to express the mass formula in terms of a small number of linearly independent operators. We show that the leading term follows a different Regge trajectory from that found for symmetric states, when plotted as a function of the band number $N$. [less ▲]

Detailed reference viewed: 33 (6 ULiège)
Full Text
Peer Reviewed
See detailLarge neighborhood search for multi-trip vehicle routing
François, Véronique ULiege; Arda, Yasemin ULiege; Crama, Yves ULiege et al

in European Journal of Operational Research (2016), 255(2), 422-441

We consider the multi-trip vehicle routing problem, in which each vehicle can perform several routes during the same working shift to serve a set of customers. The problem arises when customers are close ... [more ▼]

We consider the multi-trip vehicle routing problem, in which each vehicle can perform several routes during the same working shift to serve a set of customers. The problem arises when customers are close to each other or when their demands are large. A common approach consists of solving this problem by combining vehicle routing heuristics with bin packing routines in order to assign routes to vehicles. We compare this approach with a heuristic that makes use of specific operators designed to tackle the routing and the assignment aspects of the problem simultaneously. Two large neighborhood search heuristics are proposed to perform the comparison. We provide insights into the configuration of the proposed algorithms by analyzing the behavior of several of their components. In particular, we question the impact of the roulette wheel mechanism. We also observe that guiding the search with an objective function designed for the multi-trip case is crucial even when exploring the solution space of the vehicle routing problem. We provide several best known solutions for benchmark instances. [less ▲]

Detailed reference viewed: 79 (15 ULiège)
Full Text
See detailLarge neighborhood search for multi-trip vehicle routing
François, Véronique ULiege; Arda, Yasemin ULiege; Crama, Yves ULiege et al

E-print/Working paper (2015)

We consider two large neighborhood search approaches for the multi-trip vehicle routing problem, where each vehicle can perform several routes during the working shift to serve a set of customers. The ... [more ▼]

We consider two large neighborhood search approaches for the multi-trip vehicle routing problem, where each vehicle can perform several routes during the working shift to serve a set of customers. The problem specifically arises when customers are close to each other and/or when the demands are large. A common approach in the literature consists in solving this problem by mixing vehicle routing heuristics with bin packing routines to assign routes to vehicles. We compare this approach with the use of specific operators designed to tackle the routing and the assignment aspects of the problem simultaneously. We provide several best known solutions for benchmark instances. At the end of the work, we give insights about the proposed algorithm configurations by analyzing the behavior of several method components. [less ▲]

Detailed reference viewed: 135 (15 ULiège)
Full Text
Peer Reviewed
See detailLARGE ORGANIC-WALLED MICROFOSSILS IN MESOARCHEAN SHALLOW-MARINE SILICICLASTIC DEPOSITS
Javaux, Emmanuelle ULiege; Marshall, Craig; Bekker, Andrey

Conference (2010, June)

Detailed reference viewed: 29 (2 ULiège)
Full Text
Peer Reviewed
See detailLARGE PENETRATION OF DISTRIBUTED PRODUCTIONS: DYNAMIC LINE RATING AND FLEXIBLE GENERATION, A MUST REGARDING INVESTMENT STRATEGY AND NETWORK RELIABILITY
Schell, Peter; Lilien, Jean-Louis ULiege; Nguyen, Huu-Minh ULiege et al

Conference (2012, May)

Dynamic Line Rating (DLR), a.k.a determining the maximum rating of overhead lines based on real-time weather parameters has the potential to significantly increase the power transport & distribution ... [more ▼]

Dynamic Line Rating (DLR), a.k.a determining the maximum rating of overhead lines based on real-time weather parameters has the potential to significantly increase the power transport & distribution capacity of the grid in favorable weather conditions. Combining active network management (curtailable generation) with DLR as trigger offers a solution out-there for the <br />system operator that combines technical feasibility, adequate implementation timing and economic viability. Flexible generation being already in use on the ELIA network, the potential benefits of using it in conjunction with DLR will be analyzed. [less ▲]

Detailed reference viewed: 115 (51 ULiège)
Full Text
Peer Reviewed
See detailLarge phosphorus hyperfine coupling as a sensitive tool for studying molecular dynamics : ESR and Molecular Mechanics studies of ring interconversion in cis-2,5-diphosphoryl-2,5-dimethyl-pyrrolidinoxyl radical
Rockenbauer, Antal; Gaudel-Siri, Anouk; Siri, Didier et al

in Journal of Physical Chemistry A (2003), 107(19), 3851-3857

ESR spectra of cis- and trans-â-diphosphorylated pyrrolidine-N-oxyl radicals, c-1 and t-1, were studied in liquid and frozen solution. The expected 1:2:1 triplet (aP (2)) of the 1:1:1 triplet (aN) was ... [more ▼]

ESR spectra of cis- and trans-â-diphosphorylated pyrrolidine-N-oxyl radicals, c-1 and t-1, were studied in liquid and frozen solution. The expected 1:2:1 triplet (aP (2)) of the 1:1:1 triplet (aN) was observed for t-1; however, for c-1, the inner lines of the 1:2:1 triplet showed a dramatic broadening characteristic of chemical exchange between two equivalent conformations. Owing to the large difference in the hyperfine splitting constants (hfsc) of the exchanging phosphorus (¢aP 21 G), the coalescence temperature was unusually high (193 K, in n-pentane), and the potential barrier for ring interconversion (10.5 kJ mol-1) was easily obtained from the temperature dependence of the exchange rate. This value was in very good agreement with the value obtained for an empirical pseudorotational potential (11 kJ mol-1) that was adjusted to fit the temperature dependence of the phosphorus hfsc. For c-1, molecular mechanics calculations gave similar characteristics for the pseudorotational potential and indicated the existence of two identical minima with distorted geometries lying between 3T4 and 3E or 4T3 and E3. For t-1, only the 3T4 conformer was found to be significantly populated. Frozen solution spectra showed that the phosphorus hfsc anisotropy is higher when the C-P bond is pseudoaxial; this result can be explained by a geometry-dependent delocalization of the unpaired electron into the phosphorus 3p orbitals. [less ▲]

Detailed reference viewed: 20 (1 ULiège)
Full Text
Peer Reviewed
See detailLarge pion pole in Z(S)(MOM)/(Z(P)(MOM) from Wilson action data
Cudell, Jean-René ULiege; Le Yaouanc, A.; Pittori, C.

in Physics Letters B (2001), 516(1-2), 92-102

Detailed reference viewed: 15 (4 ULiège)
Full Text
Peer Reviewed
See detailLarge predatory marine reptiles from the Albian–Cenomanian of Annopol, Poland
Bardet, Nathalie; Fischer, Valentin ULiege; Machalski, Marcin

in Geological Magazine (2016)

During the Early–Late Cretaceous transition, marine ecosystems in Eurasia hosted a diverse set of large predatory reptiles that occupied various niches. However, most of our current knowledge of these ... [more ▼]

During the Early–Late Cretaceous transition, marine ecosystems in Eurasia hosted a diverse set of large predatory reptiles that occupied various niches. However, most of our current knowledge of these animals is restricted to a small number of bonebed-like deposits. Little is known of the geographical and temporal extent of such associations. The middle Albian – middle Cenomanian phosphorite-bearing succession exposed at Annopol, Poland produces numerous ichthyosaurian and plesiosaurian fossils. These are mostly isolated skeletal elements (e.g. teeth, vertebrae), but disarticulated partial skeletons and an articulated, sub vertically embedded ichthyosaur skull are also available. The following taxa are identified: ‘Platypterygius’ sp., cf. Ophthalmosaurinae, Ichthyosauria indet., Polyptychodon interruptus, Pliosauridae indet., Elasmosauridae<indet. and Plesiosauria indet. The large-sized ichthyosaur ‘Platypterygius’ and the pliosaurid Polyptychodon interruptus predominate within the upper Albian – middle Cenomanian deposits. The Annopol record, combined with data from England, France and western Russia, suggests that ‘Platypterygius’ and Polyptychodon interruptus formed a long-term, stable ecological sympatry in marine ecosystems of the European archipelago, at least during the Albian – middle Cenomanian. In addition, the marine reptile assemblage from Annopol is distinct from other Eurasian ecosystems in containing also elasmosaurids in its Albian portion. [less ▲]

Detailed reference viewed: 100 (8 ULiège)
Full Text
Peer Reviewed
See detailLarge review finds no clinically important effect of glucosamine or chondroitin on pain in people with osteoarthritis of the knee or hip but results are questionable and likely due to heterogeneity
Bruyère, Olivier ULiege

in Evidence-Based Medicine (2010)

Context Treatment of osteoarthritis with unspecifi c symptomatic agents is not satisfactory and burdened with safety issues. The use of glucosamine and/or chondroitin as diseasemodifying agents is ... [more ▼]

Context Treatment of osteoarthritis with unspecifi c symptomatic agents is not satisfactory and burdened with safety issues. The use of glucosamine and/or chondroitin as diseasemodifying agents is increasingly popular, despite conflicting clinical trial evidence with the many available products. Wandel and colleagues produced a systematic review and a meta-analysis with relatively new statistical methods. [less ▲]

Detailed reference viewed: 288 (12 ULiège)
Full Text
Peer Reviewed
See detailLarge ring 1,3-bridged 2-azetidinones: experimental and theoretical studies
Urbach, Allan; Dive, Georges ULiege; Tinant, Bernard et al

in European Journal of Medicinal Chemistry (2009), 44

Detailed reference viewed: 49 (7 ULiège)
Full Text
Peer Reviewed
See detailLarge Sample Size, Wide Variant Spectrum, and Advanced Machine-Learning Technique Boost Risk Prediction for Inflammatory Bowel Disease.
Wei, Zhi; Wang, Wei; Bradfield, Jonathan et al

in American Journal of Human Genetics (2013)

We performed risk assessment for Crohn's disease (CD) and ulcerative colitis (UC), the two common forms of inflammatory bowel disease (IBD), by using data from the International IBD Genetics Consortium's ... [more ▼]

We performed risk assessment for Crohn's disease (CD) and ulcerative colitis (UC), the two common forms of inflammatory bowel disease (IBD), by using data from the International IBD Genetics Consortium's Immunochip project. This data set contains ?17,000 CD cases, ?13,000 UC cases, and ?22,000 controls from 15 European countries typed on the Immunochip. This custom chip provides a more comprehensive catalog of the most promising candidate variants by picking up the remaining common variants and certain rare variants that were missed in the first generation of GWAS. Given this unprecedented large sample size and wide variant spectrum, we employed the most recent machine-learning techniques to build optimal predictive models. Our final predictive models achieved areas under the curve (AUCs) of 0.86 and 0.83 for CD and UC, respectively, in an independent evaluation. To our knowledge, this is the best prediction performance ever reported for CD and UC to date. [less ▲]

Detailed reference viewed: 12 (0 ULiège)
Full Text
Peer Reviewed
See detailLarge scale 2D numerical modelling of reservoirs sedimentation and flushing operations
Dewals, Benjamin ULiege; Erpicum, Sébastien ULiege; Archambeau, Pierre ULiege et al

in Proceedings of the 9th International Symposium on River Sedimentation (2004)

The quasi-3D flow solver WOLF has been developed at the University of Liege for almost a decade. It has been used to carry out the simulation of silting processes in large reservoirs and to predict the ... [more ▼]

The quasi-3D flow solver WOLF has been developed at the University of Liege for almost a decade. It has been used to carry out the simulation of silting processes in large reservoirs and to predict the efficiency of flushing operations. Besides briefly depicting the mathematical and numerical model, the present paper demonstrates its applicability on the case of a large hydropower project in India. The silting process of the reservoir has been simulated by means of the quasi-3D flow model with a quasi-steady approach. For simulating flushing events, both the topography changes and their interactions with the flow have been carefully handled in a strongly coupled approach. This narrow coupling has required the development of a suitable upwind numerical scheme. Results are presented with 2D- and 3D-views, completed by cross-sections and curves of the variation of key variables. The numerous observations based on those results lead to a global assessment of the silting mechanism and of the flushing efficiency. [less ▲]

Detailed reference viewed: 164 (4 ULiège)