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See detailLe cycle du fer. Physiopathologie et exploration.
Fillet, Georges ULg

in Annales Médico-chirurgicales du Hainaut (1978), 30

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See detailCycle écologique de Dunaliella salina et Artemia salina en relation avec la fluctuation des paramètres physicochimiques des eaux de la saline Sebkhet Al Hdhibet au sud tunisien
Ammar, Jihenne; Ben Ouada, Hatem; Franck, Fabrice ULg et al

in Mésogée (2013), 69

Le présent travail s’intéresse à la variation saisonnière des caractéristiques biologiques et physicochimiques des eaux de la saline de Sebkhat Al Hdhibet au sud tunisien. Des mesures biologiques (densité ... [more ▼]

Le présent travail s’intéresse à la variation saisonnière des caractéristiques biologiques et physicochimiques des eaux de la saline de Sebkhat Al Hdhibet au sud tunisien. Des mesures biologiques (densité cellulaire en Dunaliella et Artemia), physiques et chimiques ont été effectuées sur plusieurs zones du site et à différentes périodes de l’année. L’interaction entre tous ces paramètres a été évaluée, dans l’espace et dans le temps, moyennant la méthode multidimensionnelle de l’analyse factorielle en composantes principales (ACP). Les résultats montrent que ce milieu hyperhalin favorise la poussée exclusive de deux micro- organismes halophiles : Dunaliella salina et Artemia salina, et permettent de tracer le cycle écologique annuel de ces deux espèces. Les plus fortes concentrations en A. salina sont enregistrées en fin d’hiver et début du printemps lorsque les pluies diluent les sels du milieu et diminuent le pH, favorisant l’augmentation des taux de bicarbonates. En fin de printemps, D. salina atteint sa concentration maximale. En été, lorsque la température des eaux dépasse 30°C, la salinité augmente, provoquant la précipitation progressive de sels et la réduction des taux de bicarbonates dans le milieu. A l’exception des puits de pompages, qui représentent une réserve en Dunaliella, la saline se dessèche dans sa majeure partie. 24% de cellules de D. salina sont piégés dans les cristaux de sels. Les cultures réalisées au laboratoire à partir de ces cristaux montrent que ces cellules reprennent rapidement leur croissance avec des vitesses avoisinant 100 000 cellules/ml/j, en pleine phase exponentielle. [less ▲]

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See detailCycle Optimization of a Turbine Engine: an Approach Based on Genetic Algorithms
Borguet, Sébastien ULg; Kelner, Vincent ULg; Léonard, Olivier ULg

in Proceedings od the 7th Belgian Congress on Theoretical and Applied Mechanics (2006, May)

Multi-objective optimization is performed of a turbofan. The objectives are to minimize the Specific Fuel Consumption at cruise conditions, as well as to maximize the Specific Thrust during the take-off ... [more ▼]

Multi-objective optimization is performed of a turbofan. The objectives are to minimize the Specific Fuel Consumption at cruise conditions, as well as to maximize the Specific Thrust during the take-off phase. Three design variables have been selected: the by-pass ratio, the fan pressure ratio, and the high pressure compressor pressure ratio. The backbones of the optimization approach consist of a genetic algorithm and a modular gas turbine simulation tool. [less ▲]

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See detailLe cycle sexuel de la femelle des petits camélidés sud-américains
Hanzen, Christian ULg; Cucho Dolmos, Hernan; Ampuero Casquino, Enrique et al

E-print/Working paper (2015)

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See detailCycle Slips Detection in Quad-Frequency Mode: Galileo's Contribution to an Efficient Approach under Hogh Ionospheric Activity
Van de Vyvere, Laura ULg

in CLGE Student Contest (2015)

Cycle slips detection has always been a key issue in phase measurements accuracy, thus impacting positioning precision. Since Galileo is the first constellation to offer four carrier frequencies available ... [more ▼]

Cycle slips detection has always been a key issue in phase measurements accuracy, thus impacting positioning precision. Since Galileo is the first constellation to offer four carrier frequencies available in Open Service, we were able to develop an innovative detection algorithm, especially promising in harsh environment like high ionospheric activity. This improves previous dual and triple-frequency methods, whose efficiency was somehow limited in tricky situations, like ionospheric events or particular configurations. In our algorithm, two types of testing quantities were used: triple-frequency Simsky combination and dual-frequency Geometry-Free combination, each one being associated to a suitable detection algorithm. Simsky combination allows to detect almost every configuration, except for cycle slips of the same magnitude, appearing simultaneously on all carriers. Geometry-Free combination is only used to detect this particular case, since it suffers from quick variation of ionospheric delay. Together - through the choice of the most efficient combination alternatives - they enable the detection of any cycle slips configuration. This is now made possible thanks to the availability of data from Galileo’s four carriers. The quad-frequency algorithm has been tested on Galileo observations from both GMSD (Japan) and NKLG (Gabon) stations. On the first ones, cycle slips were artificially inserted in order to simulate particular cases and test algorithm robustness. NKLG raw data were used to assess algorithm behaviour for cases met in the equatorial area. Enhanced with a suitable cycle slip correction method and a real-time feature, our algorithm could directly be integrated into the software receiver, enabling the supply of continuous and corrected data to the user. In conclusion, this first quad-frequency cycle slips detection algorithm is obviously a step forward and every Galileo user will indeed be able to benefit from a highly better-quality positioning. With regard to precise positioning, this is yet another step reinforcing Galileo’s competitivity against other dual or triple-frequency GNSS. [less ▲]

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See detailCycle, cercle, compilation. Introduction
Henrard, Nadine ULg

Conference (2016, February 16)

Introduction à la journée "Cycle, cercle, compilation", s'intéressant à la constitution d'ensembles d'hommes (cercles littéraires) ou de textes (compilations, cycles) au Moyen Âge. Les questionnements ... [more ▼]

Introduction à la journée "Cycle, cercle, compilation", s'intéressant à la constitution d'ensembles d'hommes (cercles littéraires) ou de textes (compilations, cycles) au Moyen Âge. Les questionnements soulevés par cette journée touchent ainsi à tous les stades de la chaîne du texte, de l’écriture à la réception et nécessitent de conjuguer axes synchronique et diachronique, données codicologiques et littéraires, historiques et aussi sociologiques. Ils invitent à interroger la part du hasard et de l’intention qui joue dans le rassemblement des œuvres et montrent, si besoin en était encore, qu’il est indispensable d’inscrire le fait littéraire dans une dynamique globale, en rappelant que les œuvres ne sont que des pièces imbriquées dans divers systèmes avec lesquels elles entrent en dialogue. [less ▲]

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See detailCycle-based TCP-Friendly Algorithm
Ait-Hellal, Omar; Yamamoto, Lidia; Leduc, Guy ULg

in Proceedings of IEEE Globecom'99 (1999, December)

Several TCP-Friendly algorithms have been recently proposed to support multimedia applications. These algorithms try to mimic the congestion control behavior of TCP. However, the oscillatory (bursty ... [more ▼]

Several TCP-Friendly algorithms have been recently proposed to support multimedia applications. These algorithms try to mimic the congestion control behavior of TCP. However, the oscillatory (bursty) nature of TCP traffic is widely known to be unsuitable for most typical real-time applications. Adopting such behavior would result in annoying QoS oscillations for the users of such real-time applications. In the present paper we describe a new TCP-Friendly algorithm based on the TCP cycle estimation. We show through simulations that the proposed algorithm is able to smooth the oscillations while keeping fairness towards TCP. [less ▲]

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See detailLes cycles du désir sexuel (saison 2)
Kempeneers, Philippe ULg

in Sexualités humaines (2010), 6

Cette deuxième saison au pays du désir nous conduit aux confins de la passion amoureuse, entre animalité et profonde humanité

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See detailLes cycles du désir sexuel (saison 3)
Kempeneers, Philippe ULg

in Sexualités humaines (2010), 7

Au terme de ce triptyque sur le désir et ses différentes figures, un cas clinique très éclairant

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See detailCycles found in air temperature data and proxy series using the Morlet wavelet method
Nicolay, Samuel ULg; Mabille, Georges ULg; Fettweis, Xavier ULg et al

Scientific conference (2009, February 25)

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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 detailCycles of humid-dry climate conditions around the P/E boundary: New stable isotope data from terrestrial organic matter in Vasterival section (NW France)
Storme, Jean-Yves ULg; Dupuis, C.; Schnyder, J. et al

in Terra Nova (2012), 24(2), 114-122

The Palaeocene/Eocene boundary (P/EB) and the Palaeocene-Eocene Thermal Maximum (55.8Ma) are defined stratigraphically based on carbon isotope ratios of various materials. Here, the position of the P/EB ... [more ▼]

The Palaeocene/Eocene boundary (P/EB) and the Palaeocene-Eocene Thermal Maximum (55.8Ma) are defined stratigraphically based on carbon isotope ratios of various materials. Here, the position of the P/EB is refined in the terrestrial-lacustrine and swampy Vasterival section (Upper Normandy coast, France) by using carbon isotopes measured on dispersed organic matter (δ 13C org). Moreover, nitrogen isotopes on dispersed organic matter (δ 15N org) are, for the first time in the Palaeogene record, associated with carbon isotope and lithological data to constrain palaeoclimatic and environmental changes around the P/EB in a terrestrial environment. Humid-dry fluctuations before and during this key interval in Earth history are suggested. © 2012 Blackwell Publishing Ltd. [less ▲]

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See detailCyclic and oligo-carbonates by organocatalytic coupling of CO2 with epoxides or oxetanes
Alves, Margot ULg; Grignard, Bruno ULg; Boyaval, Amélie ULg et al

Conference (2016, April 20)

Valorising CO2 as a renewable C1 feedstock for producing added value building blocks is the scope of many academic and industrial researches. Carbon dioxide is a thermodynamically and kinetically stable ... [more ▼]

Valorising CO2 as a renewable C1 feedstock for producing added value building blocks is the scope of many academic and industrial researches. Carbon dioxide is a thermodynamically and kinetically stable molecule that can be converted into five and six membered cyclic carbonates by coupling with epoxides or oxetanes, respectively, using appropriate catalysts. Although transition metal catalysts are efficient under atmospheric pressure and ambient temperature, most of them are poorly selective, sensitive to hydrolysis and/or oxidation and/or toxic whereas less/non-toxic and eco-friendly organocatalysts such as ionic liquids and halide salts are generally only efficient at very high temperature and pressure favouring their thermal degradation. To overcome these limitations, we developed a new highly efficient bicomponent homogeneous organocatalyst composed of an ammonium salt as the catalyst and fluorinated single or double hydrogen bond donor activators. Through online FTIR kinetic studies, we demonstrated that this new organocatalyst showed unexpected catalytic activity for the fast and selective addition of CO2 onto epoxides under solvent-free and mild experimental conditions. The use of this dual catalyst was then extended to the coupling of CO2 with less reactive oxetanes to produce hydroxyl telechelic oligocarbonates. In the first part of this talk, based on kinetics of reactions followed by online FTIR under pressure, we will describe the reaction conditions required for the organocatalytic coupling of CO2 with epoxides and oxetanes. In the second part, the mechanism of the reaction will be approached and discussed based on DFT calculations. Finally, we will compare and discuss the efficiency of various organocatalytic systems for this type of reaction. [less ▲]

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See detailCyclic appearance of left ventricular outflow tract dynamic obstruction during mechanical ventilation: evidence for a preload dependent phenomenon.
Canivet, Jean-Luc ULg; Lancellotti, Patrizio ULg; Radermecker, Marc ULg et al

in Journal of Intensive Care Medicine (2008), 23(4), 281-4

The cyclic appearance of dynamic left ventricular outflow tract obstruction during mechanical ventilation, according to the phasic changes in preload, is described in this article. Hemodialysis-induced ... [more ▼]

The cyclic appearance of dynamic left ventricular outflow tract obstruction during mechanical ventilation, according to the phasic changes in preload, is described in this article. Hemodialysis-induced fluid removal resulted in preload dependence as evidenced by the pulse pressure variation in a 56-year-old critically ill patient. The clinical picture was suggestive of myocardial failure. Transthoracic echocardiography disclosed dynamic left ventricular outflow tract obstruction associated with systolic anterior motion of the mitral valve. Progressive fluid restitution resulted in a parallel decrease in both the degree of dynamic obstruction and pulse pressure variation. During fluid loading, dynamic obstruction disappeared at first during the inspiratory phase of intermittent positive pressure ventilation corresponding to the phasic increase in left ventricular preload. Further fluid loading resulted in the disappearance of dynamic obstruction during both inspiratory and expiratory phase of intermittent positive pressure ventilation. This is the first reported case clearly relating left ventricular outflow tract dynamic obstruction to preload dependence during mechanical ventilation in a critically ill patient without predisposing anatomical factor. [less ▲]

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See detailCyclic behaviour of cohesionless soils under seismic loading
Cerfontaine, Benjamin ULg

Diverse speeche and writing (2012)

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See detailThe cyclic behaviour of sand, from the Prevost model to offshore geotechnics
Cerfontaine, Benjamin ULg

Doctoral thesis (2014)

The main objective of this thesis is the studying of the cyclic behaviour of dense sand. Its centre of gravity is the implementation of a convenient constitutive law in the finite element code LAGAMINE ... [more ▼]

The main objective of this thesis is the studying of the cyclic behaviour of dense sand. Its centre of gravity is the implementation of a convenient constitutive law in the finite element code LAGAMINE. The first step consists in summarising the salient features of the cyclic behaviour of sand observed in laboratory tests. Undrained monotonic and cyclic experiments are addressed. The phase transformation line is a key parameter in the description of its behaviour. The plasticity effects in both loading and unloading, the progressive pore pressure accumulation coupled with the degradation of the stiffness of the soil are of uttermost importance in the cyclic behaviour. The Prevost model is adopted for its conceptual simplicity and its physically related parameters. The basic equations of the model are described and its variants are illustrated. Calibration of the required parameters is carried out by means of simplified routines implemented in Matlab. A unique set of parameters is determined for each soil at a given relative density. Monotonic experiments are well reproduced. The model also replicates satisfactorily the trend of cyclic experiments. An implicit scheme is embraced in order to implement the model in the finite element code LAGAMINE. The implicit Prager translation rule is adopted for that purpose. It is ensured the discrete formulation reproduces exactly the analytical model. Accuracy, efficiency and robustness of the model are addressed throughout triaxial and multi-axial numerical examples. A hydro-mechanical interface finite element is developed. It consists in a three-node 1D isoparametric element. It is able to reproduce fluid flows across and along the interface. The unsticking of both walls of the interface is coupled with a suction effect due to the filling of the vacuum created. The behaviour of the element is illustrated by simple 1D examples of transient consolidation of a soil column. A final application consists in the modelling of a suction caisson, part of a tripod structure for wind turbines. An axisymmetric representation of this foundation is carried out. It is assumed embedded into dense Lund sand described by the Prevost model. Monotonic and cyclic simulations are performed in both drained and partially drained conditions. The salient features of the resistance of such foundations are highlighted. Their partially drained behaviour strongly increases their transient resistance. A storm including an extreme event is employed to simulate a cyclic loading. A pseudo-random short signal and its sinusoidal equivalent representation finally lead to an identical vertical settlement. This is confirmed by a long duration storm. Finally, a cyclic diagram summarising the final settlement attained for combinations of average and cyclic vertical loads is elaborated. Keywords [less ▲]

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See detailCyclic catamenial dermatoses.
Hermanns-Lê, Trinh ULg; Hermanns, Jean François; Lesuisse, Marianne et al

in BioMed Research International (2013), 2013

Detailed reference viewed: 24 (4 ULg)
See detailCyclic esterketone compounds and processes for the synthesis and use thereof
Wautier, Henri; Laterre, Jean-Pierre; Lecomte, Philippe ULg et al

Patent (2001)

Cyclic esterketone compounds, and in particular, 2-oxepane-1,5-dione, which are useful as a monomer for the production of polymers, and in particular for the production of poly(2-oxepane-1,5-dione ... [more ▼]

Cyclic esterketone compounds, and in particular, 2-oxepane-1,5-dione, which are useful as a monomer for the production of polymers, and in particular for the production of poly(2-oxepane-1,5-dione). Processes are also disclosed for both the synthesis of this new compound and for the use (polymerization) thereof for the preparation of poly(2-oxepane-1,5-dione). The poly(2-oxepane-1,5-dione) polymers and copolymers which are obtained by use of the polymerization processes with the monomer compounds are also disclosed. [less ▲]

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