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See detailGPs working in solo practice : obstacles and motivations for working in a group ? A qualitative study
Feron, Jean-Marc; Cerexhe, F.; Pestiaux, Dominique et al

in BMC Family Practice (2003), 20(2), 167-172

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See detailGPS, Galileo and BeiDou inter-system biases estimation in relative positioning with code and phase pseudoranges
Deprez, Cécile ULiege; Warnant, René ULiege

Conference (2016, September 07)

The recent increase in the number of Global Navigation Satellite Systems (GNSS) opens new perspectives in the field of high precision positioning. Particularly, the Chinese BeiDou satellite system and the ... [more ▼]

The recent increase in the number of Global Navigation Satellite Systems (GNSS) opens new perspectives in the field of high precision positioning. Particularly, the Chinese BeiDou satellite system and the European Galileo program have experienced major progress in 2015 and 2016 with the launch of 7 and 8 satellites respectively. Associated with the ongoing GPS modernization, many more frequencies and satellites are now available. Therefore, multi-GNSS relative positioning based on overlapping frequencies should entail better accuracy and reliability in position estimations. However, the differences between satellite systems induce inter-system biases (ISBs) inside the multi-GNSS equations of observation. The combined use of L1 and L5 from GPS with E1 and E5a from Galileo, B2 from BeiDou and E5b from Galileo in zero baseline double differences (ZB DD) based on a unique pivot satellite is employed to resolve ISBs. This model removes all the satellite- and receiver-dependent error sources by differentiating and the zero baseline configuration allows atmospheric and multipath effects elimination. An analysis of the long-term stability of ISBs (GPS- Galileo and Galileo - BeiDou) is conducted onvariouspairsof receiversover large timespans. Thepossibleinfluenceof temperature variations inside the receivers over ISB values is also investigated. Our study is based on the 6 multi-GNSS receivers (2 Septentrio PolaRx4, 1 Septentrio PolaRxS, 1 Septentrio PolaRx5 and 2 Trimble NetR9) installed on the roof of our building in Liege. The estimated ISBs are then used as corrections in the multi-GNSS observation model and the resulting accuracy of multi-GNSS positioning is compared to GPS, Galileo and BeiDou standalone solutions. [less ▲]

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See detailGPS, superconducting and absolute gravimeter measurements to evaluate crustal deformation in Membach, Belgium
Van Camp, Michel; Warnant, René ULiege; Francis, Olivier et al

Conference (2002)

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See detailLe GPS, un système à tout faire ?
Warnant, René ULiege

Conference given outside the academic context (2002)

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See detailA GPS/GNSS dense network used to monitor ionospheric positioning error
Wautelet, Gilles ULiege; Lejeune, Sandrine; Warnant, René ULiege

Poster (2010, December)

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See detailGPS™ II and GPS™ III: comparison of obtained platelets concentrations
Kaux, Jean-François ULiege; Le Goff, Caroline ULiege; Renouf, Julien et al

Poster (2010, March 20)

Introduction: Recently, several researches, essentially in vitro, demonstrated the positive effects of platelets on healing process of different tissues: bones, muscles and tendons. The aim of this study ... [more ▼]

Introduction: Recently, several researches, essentially in vitro, demonstrated the positive effects of platelets on healing process of different tissues: bones, muscles and tendons. The aim of this study is to compare the obtained platelets concentration between the new GPS™ III and GPS™ II. Methods: Two blood samples of 52 mL were taken in 5 volunteers and transferred respectively in both GPS™ II and GPS™ III. These devices were centrifuged at 3200 RPM during 15 min. The platelet-rich plasma (PRP) was thus collected and transferred in 6 mL test tubes. Cells count was done using an analyser ABX Micros 60. Results and conclusion: Platelets concentrations were more important from 6.2 up to 9.2 times with GPS™ II and from 7.3 up to 8.3 times with GPS™ III compared to blood samples. Efficiency of the collected platelets was around 92% for GPS™ II and 96% for GPS™ III. Both techniques made it possible to collect platelets but, unfortunately, also a lot of red and white blood cells. None of these parameters showed any significant difference (p>0.05). Conflicts of interests: The 10 devices GPS™ II and GPS™ III were provided gracefully by the firm Biomet Biologics TTC. [less ▲]

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See detailDe graanziekten en hun behandeling
Marchal, Émile ULiege

Book published by Vandenbroeck (1922)

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See detail"Grace of the Crocodiles" Towards Deterritorialization of Culture in Robert Drewe's Grace
Delrez, Marc ULiege

in Collier, Gordon; Delrez, Marc; Fuchs, Anne (Eds.) et al Engaging with Literature of Commitment, Volume 2: The Worldly Scholar (2012)

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See detailGrade retention at the transition to secondary school: A quasi-experimental study of its consequences on relationships with parents and peers
Lecocq, Aurélie; Mathys, Cécile ULiege; Véronneau, Marie-Hélène

Conference (2014, May)

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See detailGrade Retention at the Transition to Secondary School: Using Propensity Score Matching to Identify Consequences on Psychosocial Adjustment
Mathys, Cécile ULiege; Véronneau, Marie-Hélène; Lecocq, Aurélie

in Journal of Early Adolescence (2017)

This study tested whether grade retention at the transition into secondary school had a significant impact on adolescent psychosocial adjustment. A quasi-experimental design was used in which propensity ... [more ▼]

This study tested whether grade retention at the transition into secondary school had a significant impact on adolescent psychosocial adjustment. A quasi-experimental design was used in which propensity score matching was implemented. Univariate ANCOVAs were subsequently run on a subsample of 181 students enrolled in one typical secondary school in the French-speaking region of Belgium (M = 12.91 years, 55.8% girls). These analyses revealed that retained students experienced decreases in self-esteem, perceived parental support for competence and involvement in the relationships with their parents, and intrinsic and extrinsic motivation variables. Retained students also failed to show the decrease in delinquent and aggressive behaviors and social withdrawal that was observed in matched promoted students. In sum, grade retention appears to be detrimental to early-adolescence psychosocial adjustment. To decrease rates of grade retention among adolescents, change is needed in parents’, school staff’s, and policymakers’ preconceptions that the practice has overall positive outcomes. [less ▲]

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See detailGraded-commutative nonassociative algebras: higher octonions and Krichever-Novikov superalgebras; their structures, combinatorics and non-trivial cocycles.
Kreusch, Marie ULiege

Doctoral thesis (2015)

This dissertation consists of two parts. The first one is the study of a series of real (resp. complex) noncommutative and nonassociative algebras $\bbO_{p,q}$ (resp. $\bbO_{n}$) generalizing the algebra ... [more ▼]

This dissertation consists of two parts. The first one is the study of a series of real (resp. complex) noncommutative and nonassociative algebras $\bbO_{p,q}$ (resp. $\bbO_{n}$) generalizing the algebra of octonion numbers $\bbO$. This generalization is similar to the one of the algebra of quaternion numbers in Clifford algebras. Introduced by Morier-Genoud and Ovsienko, these algebras have a natural $\bbZ_2^n$-grading ($p+q =n$), and they are characterized by a cubic form over the field $\bbZ_2.$ We establish all the possible isomorphisms between the algebras $\bbO_{p,q}$ preserving the structure of $\bbZ_2^n$-graded algebra. The classification table of $\bbO_{p,q}$ is quite similar to that of the real Clifford algebras $\cC l_{p,q}$, the main difference is that the algebras $\bbO_{n,0}$ and $\bbO_{0,n}$ are exceptional. We also provide a periodicity for the algebras $\bbO_n$ and $\bbO_{p,q}$ analogous to the periodicity for the Clifford algebras $\cC l_{n}$ and $\cC l_{p,q}$. In the second part we consider superalgebras of Krichever-Novikov (K-N) type. Krichever and Novikov introduced a family of Lie algebras with two marked points generalizing the Witt algebra and its central extension called the Virasoro algebra. The K-N Lie (super)algebras for more than two marked points were studied by Schlichenmaier. In particular, he extended the explicit formula of $2$-cocycles due to Krichever and Novikov to multiple-point situation. We give an explicit construction of central extensions of Lie superalgebras of K-N type and we establish a $1$-cocycle with values in its dual space. In the case of Jordan superalgebras related to superalgebras of K-N type, we calculate a 1-cocycle with coefficients in the dual space. [less ▲]

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See detailThe Grader layered intrusion (Havre-Saint-Pierre anorthosite, Québec) and genesis of nelsonite and other Fe-Ti-P ores
Charlier, Bernard ULiege; Sakoma, Emmanuel; Sauvé, Martin et al

in Lithos (2008), 101(3-4), 359-378

The Grader layered intrusion is part of the Havre-Saint-Pierre anorthosite in the Grenville Province (Quebec, Canada). This intrusion has a basin-like morphology and contains significant resources of ... [more ▼]

The Grader layered intrusion is part of the Havre-Saint-Pierre anorthosite in the Grenville Province (Quebec, Canada). This intrusion has a basin-like morphology and contains significant resources of Fe–Ti–P in ilmenite and apatite. Outcropping lithologies are massive oxide alternating with anorthosite layers, banded ilmenite–apatite–plagioclase rocks and layered oxide apatite (gabbro-)norites. Drill cores provide evidence for stratigraphic variations of mineral and whole rock compositions controlled by fractional crystallization with the successive appearance of liquidus phases: plagioclase and ilmenite followed by apatite, then orthopyroxene together with magnetite, and finally clinopyroxene. This atypical sequence of crystallization resulted in the formation of plagioclase–ilmenite–apatite cumulates or “nelsonites” in plagioclase-free layers. Fine-grained ferrodiorites that cross-cut the cumulates are shown to be in equilibrium with the noritic rocks. The high TiO2 and P2O5 contents of these assumed liquids explains the early saturation of ilmenite and apatite before Fe–Mg silicates, thus the nelsonites represent cumulates rather than crystallized Fe–Ti–P-rich immiscible melts. The location of the most evolved mineral and whole rock compositions several tens of meters below the top of the intrusion, forming a sandwich horizon, is consistent with crystallization both from the base and top of the intrusion. The concentrations of V and Cr in ilmenite display a single fractionation path for the different cumulus assemblages and define the cotectic proportion of ilmenite to 21 wt.%. This corresponds to bulk cotectic cumulates with ca. 8 wt.% TiO2, which is significantly lower than what is commonly observed in the explored portion of the Grader intrusion. The proposed mechanism of ilmenite-enrichment is the lateral removal of plagioclase due to its relative buoyancy in the dense ferrodiorite melt. This plagioclase has probably accumulated in other portions of the intrusion or has not been distinguished from the host anorthosite. [less ▲]

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See detailGradient Boosted Regression Trees in Scikit-Learn
Prettenhofer, Peter; Louppe, Gilles ULiege

Conference (2014, February 23)

This talk describes Gradient Boosted Regression Trees (GBRT), a powerful statistical learning technique with applications in a variety of areas, ranging from web page ranking to environmental niche ... [more ▼]

This talk describes Gradient Boosted Regression Trees (GBRT), a powerful statistical learning technique with applications in a variety of areas, ranging from web page ranking to environmental niche modeling. GBRT is a key ingredient of many winning solutions in data-mining competitions such as the Netflix Prize, the GE Flight Quest, or the Heritage Health Price. We give a brief introduction to the GBRT model and regression trees -- focusing on intuition rather than mathematical formulas. The majority of the talk is dedicated to an in depth discussion how to apply GBRT in practice using scikit-learn. We cover important topics such as regularization, model tuning and model interpretation that should significantly improve your score on Kaggle. [less ▲]

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See detailGradient boosting for kernelized output spaces
Geurts, Pierre ULiege; Wehenkel, Louis ULiege; d'Alché-Buc, Florence

in Proceedings of the 24th International Conference on Machine Learning (2007)

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See detailGradient foaming of polycarbonate/carbon nanotube based nanocomposites with supercritical carbon dioxide and their EMI shielding performances
Monnereau, Laure; Urbanczyk, Laetitia; Thomassin, Jean-Michel ULiege et al

in Polymer (2015), 59

Sorption and diffusion of supercritical carbon dioxide (scCO2) into polycarbonate (PC) nanocomposites loaded with 0, 1 and 2 wt% of multi-walled carbon nanotubes (MWNTs) have been investigated. After ... [more ▼]

Sorption and diffusion of supercritical carbon dioxide (scCO2) into polycarbonate (PC) nanocomposites loaded with 0, 1 and 2 wt% of multi-walled carbon nanotubes (MWNTs) have been investigated. After determination of the saturation equilibrium, the samples have been saturated with scCO2 to ensure a partial foaming with a density gradient from the surface to the center of the samples and the morphology of the porous materials has been analysed by SEM. The gradient materials were very advantageous for EMI shielding since the foamed structure at the surface had low dielectric constant and limited the reflection of the EM signal while the presence of highly conductive solid in the middle ensured a high absorption of the electromagnetic radiation. [less ▲]

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See detailGradient of proteolytic enzymes, their inhibitors and matrix proteins expression in a ruptured abdominal aortic aneurysm
Defawe, O. D.; Colige, Alain ULiege; Lambert, Charles ULiege et al

in European Journal of Clinical Investigation (2004), 34(7), 513-514

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See detailGradient urbain-rural de la ville de Lubumbashi: dynamique entre 2002 et 2009
Andre, Marie ULiege; Bogaert, Jan ULiege; Mahy, Grégory ULiege et al

in Ernoult, Aude (Ed.) Dynamiques écologiques des paysages: de l'agricole à l'urbain (2013, June 12)

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See detailGradient urbain-rural de la ville de Lubumbashi: dynamique entre 2002 et 2009
Andre, Marie ULiege; Mahy, Grégory ULiege; Lejeune, Philippe ULiege et al

Conference (2013, June 12)

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See detailGradient-elution parameters in capillary liquid chromatography for high-speed separations of peptides and intact proteins
Vaast, A.; Tyteca, Eva ULiege; Desmet, G. et al

in Journal of Chromatography. A (2014), 1355

This contribution relates to the assessment of gradient-elution parameters in capillary liquid chromatography affecting the peak widths in the reversed-phase separation of peptides and intact proteins ... [more ▼]

This contribution relates to the assessment of gradient-elution parameters in capillary liquid chromatography affecting the peak widths in the reversed-phase separation of peptides and intact proteins. Gradient separations were performed using both a poly(sytrene-co-divinylbenzene) monolithic column and a microparticulate fused-core column (silica C18, 2.7μm). The applicability of the conventional linear (LSS) and non-linear solvent-strength model (Neue-Kuss) were investigated to describe the retention behaviour of the compounds as a function of the mobile-phase composition. This was performed by using a wide range of gradient conditions, including different gradient slopes (β, ranging from 0.05 to 0.65min-1) and mobile-phase compositions (δφ, i.e. gradient span). Although the LSS-model provided accurate retention time predictions (<1.3% deviation) of scouting runs with more conventional gradient slopes, the prediction of high-speed separations with a high degree of accuracy (<2%) could only be obtained with the non-linear model. The solvent-strength parameters resulting from the use of both models, as well as the retention factors at the moment of elution (ke), further served as input parameters to assess the influence of the gradient slope on the expected peak-compression effects in gradient mode, with a focus on high-speed separations. The importance of the correct model choice was emphasized in terms of compression; while the LSS-model lead to the conclusion of peak broadening rather than peak sharpening, the use of a more accurate non-linear model showed the existence of peak compression effect. The results presented in this manuscript show the occurrence of gradient-related focusing effects, which appear to be more prevalent for extremely fast separations. © 2014 Elsevier B.V. [less ▲]

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