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See detailLine-profile variablity in the spectrum of WR22 around periastron: binary interaction or intrinsic variability ?
Rauw, Grégor ULg; Vreux, Jean-Marie ULg; Gosset, Eric ULg

in Liege International Astrophysical Colloquia (1996)

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See detailLinear and curvilinear effects of inbreeding on production traits for walloon Holstein cows
Croquet, Coraline; Mayeres, Patrick; Gillon, Alain ULg et al

in Journal of Dairy Science (2007), 90(1), 465-471

The nonlinear effects of inbreeding were studied by comparing linear and curvilinear regression models of phenotypic performances on inbreeding coefficients for production traits (milk, fat, and protein ... [more ▼]

The nonlinear effects of inbreeding were studied by comparing linear and curvilinear regression models of phenotypic performances on inbreeding coefficients for production traits (milk, fat, and protein yields) of Holstein cows in their first lactation. Three different regression models (linear, quadratic, and cubic) were introduced separately into a single-trait, single-lactation, random regression test-day model. The significance of the different regression coefficients was studied based on a t-test after estimation of error variances and covariances associated with the different regression coefficients. All of the tested regression coefficients were significantly different from 0. The traditional regression coefficients of milk, fat, and protein yields on inbreeding were, respectively, -22.10, -1.10, and -0.72 kg for Holstein cows in their first lactation. However, the estimates of 305-d production losses for various classes of animals based on inbreeding coefficients showed that the effect of inbreeding was not a linear function of the percentage of inbreeding. The 305-d milk yield loss profiles attributable to inbreeding, obtained by the various regression models, were different. However, for inbreeding coefficients between 0 and 10%, these differences were small. [less ▲]

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See detailLinear and loglinear structural mean models to evaluate the benefits of an on-demand dosing regimens
Comté, Laetitia ULg; Vansteelandt, Stijn; Tousset, Eric et al

in Clinical Trials : Journal of the Society for Clinical Trials (2009), 6(5), 403-415

Background Structural mean models (SMM) can be used to estimate treatment efficacy when drug exposure varies. We applied SMM to evaluate the clinical benefits of a proton pump inhibitor prescribed to be ... [more ▼]

Background Structural mean models (SMM) can be used to estimate treatment efficacy when drug exposure varies. We applied SMM to evaluate the clinical benefits of a proton pump inhibitor prescribed to be taken as needed to alleviate epigastric pain. We also investigated a new diagnostic approach to evaluate model assumptions. Methods All patients were suffering from non-erosive reflux disease or functional ulcer-like dyspepsia and were prescribed a proton pump inhibitor to be taken as needed for relief of epigastric pain. The primary endpoint was a score variable that expresses the magnitude of gastro-intestinal symptoms at 8 weeks after randomization. We developed linear and loglinear versions of the SMM to derive an unbiased estimator of the reduction in symptom score as a function of exposure to the test drug. Semi-parametric models based on splines and corresponding simultaneous confidence bands identified the presence of potential interactions between drug exposure and baseline covariates. Results The on-demand dosing regimen generated a wide range of drug exposure. Application of SMM showed that the potential treatment induced reduction in symptom score was much greater than the average treatment reduction observed in this population of patients. Our diagnostic tool was useful for detecting the interaction between drug exposure and baseline covariates. Limitations Analysis could only be performed over the two first months after randomization because, afterwards, many patients dropped out from the placebo group. Conclusions The structural mean model approach allows one to estimate treatment efficacy in the presence of variable drug exposure. Similar results were obtained using linear and loglinear SMM. [less ▲]

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See detailLinear and Non-Linear Transonic Flow Behaviour of the Goland+ wing
Vio, Gareth Arthur; Dimitriadis, Grigorios ULg; Cooper, Jonathan Edward et al

in Proceedings of the 2007 International Forum on Aeroelasticity and Structural Dynamics (2007, June)

This paper is part of a study investigating the prediction of the aeroelastic behavior of aircraft subjected to transonic aerodynamic forces. The main objective of the work is the creation of Reduced ... [more ▼]

This paper is part of a study investigating the prediction of the aeroelastic behavior of aircraft subjected to transonic aerodynamic forces. The main objective of the work is the creation of Reduced Order Models from coupled Computational Fluid Dynamic and Finite Element calculations. The novelty of the approach lies in the identification of different types of Reduced Order Model in different flight regimes. Linear modal models are used in the Mach range range where the full CFD/CSD system is linear and nonlinear modal models in the transonic flight regime where the CFD/CSD system undergoes Limit Cycle Oscillations. Static solutions of the CFD/CSD system are used in order to determine the extent of the nonlinear Mach number range. The model treated in this work is a three-dimensional wing in a transonic flowfield. [less ▲]

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See detailLinear and nonlinear analyses of convective instabilities in evaporating liquid layers
Dauby, Pierre ULg; Dondlinger, Mireille; Marjerit, Jonathan et al

in Bulletin of the American Physical Society, Vol. 45, n°9 (2005, November)

The present work consists in a theoretical study of Rayleigh- B'enard-Marangoni instabilities in an evaporating horizontal liquid layer which is surmounted by a mixture of its vapour and an inert gas. The ... [more ▼]

The present work consists in a theoretical study of Rayleigh- B'enard-Marangoni instabilities in an evaporating horizontal liquid layer which is surmounted by a mixture of its vapour and an inert gas. The fluid and the gas mixture form a 2-layer system but simplified models can be built to analyse the behaviour of the system. In particular, a 1-layer model can be deduced by introducing a generalized Biot number. In the so- called 1.5-layer approximation, the behaviour of the gas is simplified by only keeping the linear equation of vapour diffusion. In the linear study of thermoconvective instabilities, both simplified models are shown to be in good agreement with the complete 2-layer system. For the non linear approach, only the simplified models are considered. A Galerkin-Eckhaus method is used to deduce amplitude equations for the weakly nonlinear analysis of the problem. The stability domains for the rolls, squares and hexagonal patterns emerging above threshold are determined. Both water and ethanol are used as fluids, while the inert gas is assumed to be air. [less ▲]

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See detailLinear and nonlinear analyses of convective instabilities in evaporating liquid layers
Dondlinger, M.; Margerit, J.; Dauby, Pierre ULg

in On Interfacial Fluid Dynamics And Processes in phyisico-chemical systems (2004)

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See detailLinear and nonlinear Rayleigh-Bénard-Marangoni instability with surface deformations
Regnier, Vincent; Dauby, Pierre ULg; Lebon, Georgy ULg

in Physics of Fluids (2000), 12

Thermoconvective instabilities in a bilayer liquid-gas system with a deformed interface are investigated. In the first part of the work which is devoted to a linear approach, emphasis is put on the role ... [more ▼]

Thermoconvective instabilities in a bilayer liquid-gas system with a deformed interface are investigated. In the first part of the work which is devoted to a linear approach, emphasis is put on the role of the upper gas layer on the instability phenomenon. The condition to be satisfied by the gas to remain purely conductive is established. The so-called Oberbeck-Boussinesq approximation is discussed and its range of validity is carefully defined. Instead of the classical Rayleigh, Marangoni, crispation, and Galileo numbers, new dimensionless groups are introduced. A critical comparison with several previous works is made. The nonlinear analysis consists in studying the different convective patterns which can appear above the threshold. Particular attention is devoted to the shape of the interface and the so-called ``hybrid'' relief. The amplitude of the deformation is also determined and comparison with experimental data is discussed. [less ▲]

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See detailLinear and nonlinear thermal instability of a rotating saturated porous medium heated from below
Desaive, Thomas ULg; Hennenberg, M.; Lebon, Georgy ULg

in 1st international conference on applications of porous media (2002)

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See detailLinear Benard-Marangoni instability in rigid circular containers
Dauby, Pierre ULg; Lebon, Georgy ULg; Bouhy, E.

in Physical Review. E : Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics (1997), 56(1), 520-530

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See detailLinear coupling between the Rayleigh-Bénard instability and rotation for a ferrofluid in a normal magnetic fluid
Hennenberg, M.; Weyssow, B.; Desaive, Thomas ULg et al

in The first international conference on applications of porous media (2002)

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See detailLinear foreign bodies in cats
Hamaide, Annick ULg

in Proceedings du 15th congrès FECAVA (2009, November)

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See detailLinear formulation of identifying cdes in graphs
Vandomme, Elise ULg; Gravier, Sylvain; Parreau, Aline ULg

Poster (2013, September 09)

Identifying codes were introduced by Karpovsky, Chakrabarty and Levitin in 1998 and can be applied to locate fire in a building using sensors. Buildings are modelled by graphs with rooms as vertices. The ... [more ▼]

Identifying codes were introduced by Karpovsky, Chakrabarty and Levitin in 1998 and can be applied to locate fire in a building using sensors. Buildings are modelled by graphs with rooms as vertices. The placement of sensors in the rooms corresponds to choosing a subset of vertices. Finding a sensor-placement such that the location of a fire in one room can be precisely determined is equivalent to constructing an identifying code in the graph. These are dominating sets of vertices for which the closed neighbourhood of each vertex (i.e., the vertex and its neighbours) has a unique intersection with the set. The problem of finding an identifying code has been widely studied. Yet its formulation as an integer linear problem hasn't been much considered. Let G be a graph with vertex set V, to an identifying code $C\subseteq V$ of $G$ correspond weights x_u (x_u is 1 if u belongs to C, otherwise x_u is 0) satisfying the following : for all vertices u,v * the sum of the x_w for w in the closed neighbourhood of u is at least 1 * the sum of the x_w for w in the symmetric difference of the closed neighbourhoods of u and v is at least 1. Of course, it is interesting to find an identifying code with the smallest possible cardinality. But in general this is a NP-hard problem. A way to obtain bounds on the minimal cardinality is to consider the associated linear problem where the weights x_u are fractional. In the case of vertex-transitive graphs, the minimal cardinality for the fractional case can only take two values which depend on the number of vertices, the degree of the graph and the smallest symmetric difference between any two closed neighbourhoods. We show that for an infinite family of graphs the bound is tight and for another another the bound is far too be reached. [less ▲]

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See detailLinear magnetoelectric effect by orbital magnetism
Scaramucci, A.; Bousquet, Eric ULg; Fechner, M. et al

in Physical Review Letters (2012), 109(19),

We use symmetry analysis and first-principles calculations to show that the linear magnetoelectric effect can originate from the response of orbital magnetic moments to the polar distortions induced by an ... [more ▼]

We use symmetry analysis and first-principles calculations to show that the linear magnetoelectric effect can originate from the response of orbital magnetic moments to the polar distortions induced by an applied electric field. Using LiFePO 4 as a model compound we show that spin-orbit coupling partially lifts the quenching of the 3d orbitals and causes small orbital magnetic moments (μ (L)≈0.3μ B) parallel to the spins of the Fe2 + ions. An applied electric field E modifies the size of these orbital magnetic moments inducing a net magnetization linear in E. © 2012 American Physical Society. [less ▲]

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See detailLinear regression under fixed-rank constraints: a Riemannian approach
Meyer, Gilles ULg; Bonnabel, Silvère; Sepulchre, Rodolphe ULg

in Proceedings of the 28th International Conference on Machine Learning (2011)

In this paper, we tackle the problem of learning a linear regression model whose parameter is a fixed-rank matrix. We study the Riemannian manifold geometry of the set of fixed-rank matrices and develop ... [more ▼]

In this paper, we tackle the problem of learning a linear regression model whose parameter is a fixed-rank matrix. We study the Riemannian manifold geometry of the set of fixed-rank matrices and develop efficient line-search algorithms. The proposed algorithms have many applications, scale to high-dimensional problems, enjoy local convergence properties and confer a geometric basis to recent contributions on learning fixed-rank matrices. Numerical experiments on benchmarks suggest that the proposed algorithms compete with the state-of-the-art, and that manifold optimization offers a versatile framework for the design of rank-constrained machine learning algorithms. [less ▲]

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See detailLinear Repeating Points [chap. 13]
Wolper, Pierre ULg

in Kuper, Gabi; Libkin, Leonid; Paredaens, Jan (Eds.) Constraint Databases (2000)

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See detailLinear stability analysis of an evaporating binary liquid layer with fully transient reference profiles
Machrafi, Hatim ULg; Rednikov, Alexey; Colinet, Pierre et al

in Bulletin of the American Physical Society, Vol. 55, n°16 (2010)

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See detailA linear-quadratic model of cell survival considering both sublethal and potentially lethal radiation damage
Rutz, HP; COUCKE, Philippe ULg; Mirimanoff, RO

in Radiotherapy & Oncology (1991), 21(4), 273-276

We assessed the dose-dependence of repair of potentially lethal damage in Chinese hamster ovary cells x-irradiated in vitro. The recovery ratio (RR) by which survival (SF) of the irradiated cells was ... [more ▼]

We assessed the dose-dependence of repair of potentially lethal damage in Chinese hamster ovary cells x-irradiated in vitro. The recovery ratio (RR) by which survival (SF) of the irradiated cells was enhanced increased exponentially with a linear and a quadratic component, namely xi and psi: RR = e xi D + psi D2. Survival of irradiated cells can thus be expressed by a combined linear-quadratic model considering four variable, namely alpha and beta for the capacity of the cells to accumulate sublethal damage, and xi and psi for their capacity to repair potentially lethal damage: SF = e(xi - alpha)D + (psi - beta)D2. [less ▲]

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See detailLa linéarité comme métadiscours dans l’oeuvre de Murray Bail
Herbillon, Marie ULg

in MethIS : Méthodes et Interdisciplinarité en Sciences Humaines (2008), 1

Si d’aucuns ont relevé, chez Murray Bail, une propension à la géométrisation des espaces textuels, nul n’a souligné la fonction politico-parodique de la ligne droite dans l’oeuvre de cet écrivain ... [more ▼]

Si d’aucuns ont relevé, chez Murray Bail, une propension à la géométrisation des espaces textuels, nul n’a souligné la fonction politico-parodique de la ligne droite dans l’oeuvre de cet écrivain australien contemporain. En feignant de souscrire à la culture de la linéarité, ce dernier vise pourtant à la dénoncer et, avec elle, un certain héritage occidental. Cette réflexion prend, à l’occasion, un tour métafictionnel : bien que ses intentions parodiques aient pu le contraindre à emprunter au réalisme traditionnel certains de ses codes narratifs, Bail a longtemps cherché à discréditer ce genre littéraire trop linéaire. Avec Eucalyptus (1998), l’auteur parvient toutefois à transcender la linéarité structurelle apparente de ses premiers romans. Cet article explore les manières dont Bail s’est approprié le réalisme et/ou l’a transgressé pour, en définitive, mieux l’intégrer à la littérature australienne. [less ▲]

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See detailLinearity and stationarity of the pharmacokinetics of tiludronate in horses
Delguste, Catherine ULg; Doucet, Michèle; Amory, Hélène ULg et al

Poster (2005)

Two studies were conducted in order to assess the linearity and stationarity of the pharmacokinetics of tiludronate in horses. For each study, plasma concentrations of tiludronate were measured by HPLC-UV ... [more ▼]

Two studies were conducted in order to assess the linearity and stationarity of the pharmacokinetics of tiludronate in horses. For each study, plasma concentrations of tiludronate were measured by HPLC-UV at regular intervals and noncompartmental analysis was performed. First, single intravenous administrations of 0.05 (group 1, n = 5), 0.1 (group 2, n = 5) and 0.2 mg/kg (group 3, n = 5) were performed in healthy male adult horses. A linear relationship between groups was found for C5min (C5min = 0.0726 + 11.8589 * dose) as well as for AUC0-inf (AUC0-inf = -0.632561 + 30.9649 * dose). Clearance ranged from 0.033 to 0.044 L/h/kg and was not significantly different between groups. MRT (h) were 3.96, 4.95 and 9.40 and VDss (L/kg) were 0.16, 0.19 and 0.28 for the 0.05, 0.1 and 0.2 mg/kg doses respectively. Second, 10 daily intravenous administrations at a dosage rate of 0.1 mg/kg were administered to 4 healthy horses. Plasma tiludronate concentrations were measured after the 1st and 10th dose as well as 8 hours after each dose. The mean plasma accumulation ratio between the 1st and the 10th dose was 1.31 ± 0.48. Medians of the tiludronate concentration values measured in plasma 8 hours post-dose were not statistically different between doses. Maximum and minimum concentrations of tiludronate (mg/L) following the last dose were 0.91 and 0.04 respectively. It was concluded that the pharmacokinetics of tiludronate in horses are linear from 0.05 to 0.2 mg/kg IV and stationary after 10 IV administrations of 0.1 mg/kg. [less ▲]

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