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See detailUsing platelet-rich plasma to treat jumper’s knees: Exploring the effect of a second closely-timed infiltration
Kaux, Jean-François ULiege; Croisier, Jean-Louis ULiege; Forthomme, Bénédicte ULiege et al

in Journal of Science and Medicine in Sport (2016), 19(3), 200-204

Some clinical series have evaluated the effect of platelet-rich plasma (PRP) in the treatment of proximal patellar tendinopathy. Although it is possible that a single infiltrative administration may prove ... [more ▼]

Some clinical series have evaluated the effect of platelet-rich plasma (PRP) in the treatment of proximal patellar tendinopathy. Although it is possible that a single infiltrative administration may prove to be an effective treatment for this indication, most of the existing studies evaluated the effects of two or three successive infiltrations. The aim of this study was to evaluate whether two infiltrations of PRP proves more effective than a single treatment. DESIGN: Prospective, randomized and comparative study of level 2. METHODS: Twenty patients suffering from chronic proximal patellar tendinopathy were enrolled into the study and split into two randomized groups (one or two infiltrations of PRP, respectively). The 3-month follow-up evaluation consisted of VAS, IKDC and VISA-P scores, along with algometer, isokinetic and ultrasounds evaluations. After 1 year, subjects were contacted to define their functional evolution. RESULTS: The concentration of the PRP used for each infiltration was similar in both groups, and contained no red or white cells. Results revealed no difference in treatment efficacy between the groups. CONCLUSIONS: The comparison between one or two infiltrations of PRP did not reveal any difference between the two groups at short to mid term. A second closely-timed infiltration of PRP to treat proximal patellar tendinopathies is not necessary to improve the efficacy of this treatment in the short term. [less ▲]

Detailed reference viewed: 94 (37 ULiège)
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See detailUsing prior knowledge to accelerate online least-squares policy iteration
Busoniu, Lucian; De Schutter, Bart; Babuska, Robert et al

in Proceedings of the 2010 IEEE International Conference on Automation, Quality and Testing, Robotics (2010, May)

Reinforcement learning (RL) is a promising paradigm for learning optimal control. Although RL is generally envisioned as working without any prior knowledge about the system, such knowledge is often ... [more ▼]

Reinforcement learning (RL) is a promising paradigm for learning optimal control. Although RL is generally envisioned as working without any prior knowledge about the system, such knowledge is often available and can be exploited to great advantage. In this paper, we consider prior knowledge about the monotonicity of the control policy with respect to the system states, and we introduce an approach that exploits this type of prior knowledge to accelerate a state-of-the-art RL algorithm called online least-squares policy iteration (LSPI). Monotonic policies are appropriate for important classes of systems appearing in control applications. LSPI is a data-efficient RL algorithm that we previously extended to online learning, but that did not provide until now a way to use prior knowledge about the policy. In an empirical evaluation, online LSPI with prior knowledge learns much faster and more reliably than the original online LSPI. [less ▲]

Detailed reference viewed: 28 (3 ULiège)
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See detailUsing Proper Orthogonal Decomposition and Dynamic Mode Decomposition Methods for Comparing CFD Results Experimental Measurements
Guissart, Amandine ULiege; Andrianne, Thomas ULiege; Dimitriadis, Grigorios ULiege et al

in Proceedings of the 15th International Forum on Aeroelasticity and Structural Dynamics, IFASD 2013 (2013, June 26)

A method for the quantitative comparison of numerical and/or experimental data of unsteady aerodynamics around static and oscillating bodies is introduced. It is based on Proper Orthogonal Decomposition ... [more ▼]

A method for the quantitative comparison of numerical and/or experimental data of unsteady aerodynamics around static and oscillating bodies is introduced. It is based on Proper Orthogonal Decomposition (POD) and Dynamic Mode Decomposition (DMD) to extract the dominant structures of the unsteady flow. The proposed method is applied to spatio-temporal data for the flow around a 4:1 rectangular cylinder. Exper- imental data are obtained from wind tunnel testing and two dimensional Time-resolved Particle Image Velocimetry (Tr-PIV) measurements, while unsteady Reynolds Averaged Navier-Stokes (uRANS) are used to compute numerical results. It is demonstrated that the two approaches are complementary and represent a powerful tool that enables the analysis and the quantitative comparison of the main spatial (POD) and temporal (DMD) characteristics of unsteady aerodynamic data. [less ▲]

Detailed reference viewed: 241 (78 ULiège)
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See detailUsing Proper Orthogonal Decomposition Methods for Comparing CFD Results to Experimental Measurements
Andrianne, Thomas ULiege; Guissart, Amandine ULiege; Terrapon, Vincent ULiege et al

Scientific conference (2012, December 07)

This work presents a method for quantitative comparison of numerical results to experimental measurements. It is based on the concept of Proper Orthogonal Decomposition. This technique is selected in ... [more ▼]

This work presents a method for quantitative comparison of numerical results to experimental measurements. It is based on the concept of Proper Orthogonal Decomposition. This technique is selected in order to compare the unsteady aerodynamic flows around static and oscillating bodies obtained from wind tunnel testing and numerical simulations. Two dimensional Time-resolved Particle Image Velocimetry measurements are carried out on the upper surface a 4:1 rectangular cylinder. Simulations are performed using unsteady Reynolds-Averaged Navier-Stokes and an unsteady Discrete Vortex Method. It is demonstrated that the proposed technique is a good preliminary step for comparing the main characteristics of unsteady aerodynamic data. [less ▲]

Detailed reference viewed: 79 (30 ULiège)
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See detailUsing Proper Orthogonal Decomposition Methods for Comparing CFD Results to Experimental Measurements
Andrianne, Thomas ULiege; Guissart, Amandine ULiege; Terrapon, Vincent ULiege et al

in Proceedings of the 5th Symposium on Integrating CFD and Experiments in Aerodynamics (Integration 2012) (2012, October 03)

This work presents a method for quantitative comparison of numerical results to experimental measurements. It is based on the concept of Proper Orthogonal Decomposition. This technique is selected in ... [more ▼]

This work presents a method for quantitative comparison of numerical results to experimental measurements. It is based on the concept of Proper Orthogonal Decomposition. This technique is selected in order to compare the unsteady aerodynamic flows around static and oscillating bodies obtained from wind tunnel testing and numerical simulations. Two dimensional Time-resolved Particle Image Velocimetry measurements are carried out on the upper surface a 4:1 rectangular cylinder. Simulations are performed using unsteady Reynolds-Averaged Navier-Stokes and an unsteady Discrete Vortex Method. It is demonstrated that the proposed technique is a good preliminary step for comparing the main characteristics of unsteady aerodynamic data. [less ▲]

Detailed reference viewed: 294 (48 ULiège)
Peer Reviewed
See detailUsing putative anti-auxins to improve somatic embryo maturation of Abies nordmanniana
Tahiri, Abdelghani ULiege; Misson, Jean-Pierre; Kevers, Claire et al

Poster (2011)

In Belgium, the culture of Nordmann fir (Abies nordmanniana) is mainly located in Wallonia region. The planted area is estimated in average at 5000 ha  that annualy produce some 4 million Christmas trees ... [more ▼]

In Belgium, the culture of Nordmann fir (Abies nordmanniana) is mainly located in Wallonia region. The planted area is estimated in average at 5000 ha  that annualy produce some 4 million Christmas trees destined in priority to the export market. In vitro propagation by somatic embryogenesis is considered as an alternative method to seedlings for producing homogeneous and orthotropic trees on a large scale. Currently, the performances of the somatic embryo (SE) maturation is still insufficient to consider any commercial application of the technology. In this way , the effect of three substances  (2,3,5-triiodobenzoïque acid  as TIBA, 2 - (p-chlorophenoxy)-2-methylpropionic acids as PCIB, p-hydroxbenzoïque as PHBA)  reported as ''anti-auxins'' have been tested with three embryogenic lines on the formation and maturation of normal somatic embryos. [less ▲]

Detailed reference viewed: 53 (8 ULiège)
See detailUsing R for conducting psychometric research
Magis, David ULiege

Scientific conference (2013, October 31)

R is a statistical environment that permits to perform many various analyses, from basic descriptive statistics to advanced and complex modeling through high-level graphical features. In addition, it is ... [more ▼]

R is a statistical environment that permits to perform many various analyses, from basic descriptive statistics to advanced and complex modeling through high-level graphical features. In addition, it is open-source software with thousands of users worldwide and with (almost) daily improvements by the development of additional packages. The purpose of this talk is twofold: (a) to provide a broad overview of R (in its basic form), RStudio (software for optimized display of R components) and R Commander (an add-on package with menus and toolboxes for R); and (b) to describe and illustrate the functioning of several R packages related to psychometrics in general and item response theory in particular. The talk will be at a theoretical low-level, focusing rather on applications and illustrations with examples. Topics to be covered may include (depending on time constraints): calibration of item response models, ability estimation, model checking, differential item functioning, computerized adaptive testing. Some information about the creation and compilation of R packages will also be given. References: R Core Team (2013). R: A language and environment for statistical computing. R Foundation for Statistical Computing, Vienna, Austria. URL http://www.R-project.org/. [less ▲]

Detailed reference viewed: 89 (5 ULiège)
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See detailUsing recorded images for political purposes
Delhalle, Nancy ULiege

in Theater Topics (2012), 5

Detailed reference viewed: 27 (2 ULiège)
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See detailUsing reflection triggers while learning in an online course
Verpoorten, Dominique ULiege; Westera, Wim; Specht, Marcus

in British Journal of Educational Technology (2012), 43(6), 1030-1040

This paper reports about a controlled experiment on the effects of three types of reflection triggers in an online course. 54 volunteers, distributed in 5 groups, used these structured opportunities for ... [more ▼]

This paper reports about a controlled experiment on the effects of three types of reflection triggers in an online course. 54 volunteers, distributed in 5 groups, used these structured opportunities for reflection during learning. Results show that reflection triggers were extensively employed by the test persons and were perceived as quite useful to reflection and learning. Test persons in the experimental groups reported significantly more reflective tools and more intensive reflection than those in the control group. In contrast, no positive effects on learner performance and retention could be established. This paradox elicits different possible explanations which are discussed in the light of the common pedagogical claim that more thoughtful approaches to learning should be promoted. [less ▲]

Detailed reference viewed: 102 (24 ULiège)
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See detailUsing remote sensing (optical and radar) and modeling to support the irrigation management of cereals in a semi-arid region: a case study of the Tadla irrigated perimeter in Morocco
Benabdelouahab, Tarik ULiege

Doctoral thesis (2015)

Summary Irrigated agriculture is an important strategic sector in Morocco, it accounts for about 45%, on average, of the agricultural Gross Domestic Product, contributing thus to food security and ... [more ▼]

Summary Irrigated agriculture is an important strategic sector in Morocco, it accounts for about 45%, on average, of the agricultural Gross Domestic Product, contributing thus to food security and employment. It occupies 15% (about 1.5 million ha) of the total cultivated area in the country. Irrigation scheme managers need to ensure that water is optimally used in the irrigated perimeters and that water shortages are avoided. For large areas under irrigation, this can be achieved through water monitoring at plot level using modeling and satellite-based methodologies. The main objective of this research was to assess the use of optical and radar remote sensing and of crop modeling in the irrigation monitoring and management of wheat in the irrigated perimeter of Tadla. The potential of spectral indices derived from SPOT-5 images was explored for comparing, quantifying and mapping surface water content changes at regional and local levels. Indices were computed using the reflectance in red, near infrared and shortwave infrared bands. Our findings show that the normalized difference water index (NDWIRog) could be used to estimate and map the surface water content of wheat plots, from bare soil to fully covered soil. Backscatter threshold values derived from SAR images were used to detect irrigation water supplies in wheat plots and the optimal acquisition frequency of SAR images was determined in order to ensure continuous monitoring. A field crop model (AquaCrop) was adjusted to simulate durum wheat yields and the temporal evolution of soil moisture status in order to manage and schedule irrigation water supplies and assess their impact on yield. Currently, the approaches described in this paper are being applied independently. This research was intended, therefore, to provide tools to help policy-makers and stakeholders improve irrigation monitoring and mitigate wheat water stress at the field and irrigation perimeter levels in semi-arid areas. Keywords: irrigation management, spectral index, wheat, backscattering, SAR, semi-arid, Morocco. [less ▲]

Detailed reference viewed: 120 (20 ULiège)
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See detailUsing S-Monovette° lower the rate of hemolysed specimen from a belgian academic emergency department
VRANKEN, Laura ULiege; DELCOUR, Sandra ULiege; CAVALIER, Etienne ULiege

in Clinical Chemistry & Laboratory Medicine (2015, October)

Detailed reference viewed: 31 (1 ULiège)
See detailUsing SAR of ERS1 for evaluation of natural risks in the Andes (Ecuador)
Ozer, Pierre ULiege; Cornet, Yves ULiege; Moreno, A. et al

Poster (1994)

Detailed reference viewed: 29 (7 ULiège)
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See detailUsing seismic inversions to obtain an indicator of internal mixing processes in main-sequence solar-like stars
Buldgen, Gaël ULiege; Dupret, Marc-Antoine ULiege; Reese, Daniel Roy

in Astronomy and Astrophysics (2015)

Context. Currently, seismic modelling is one of the best ways of building accurate stellar models, thereby providing accurate ages. However, current methods are affected by simplifying assumptions ... [more ▼]

Context. Currently, seismic modelling is one of the best ways of building accurate stellar models, thereby providing accurate ages. However, current methods are affected by simplifying assumptions concerning stellar mixing processes. In this context, providing new structural indicators that are less model-dependent and more sensitive to mixing processes is crucial. Aims. We wish to build a new indicator for core conditions (i.e. mixing processes and evolutionary stage) on the main sequence. This indicator tu should be more sensitive to structural differences and applicable to older stars than the indicator t presented in a previous paper. We also wish to analyse the importance of the number and type of modes for the inversion, as well as the impact of various constraints and levels of accuracy in the forward modelling process that is used to obtain reference models for the inversion. Methods. First, we present a method of obtaining new structural kernels in the context of asteroseismology. We then use these new kernels to build a new indicator of central conditions in stars, denoted tu, and test it for various effects including atomic diffusion, various initial helium abundances, and various metallicities, following the seismic inversion method presented in our previous paper. We then study the indicator’s accuracy for seven different pulsation spectra including those of 16CygA and 16CygB and analyse how it depends on the reference model by using different constraints and levels of accuracy for its selection Results. We observe that the inversion of the new indicator tu using the SOLA method provides a good diagnostic for additional mixing processes in central regions of stars. Its sensitivity allows us to test for diffusive processes and chemical composition mismatch. We also observe that using modes of degree 3 can improve the accuracy of the results, as well as using modes of low radial [less ▲]

Detailed reference viewed: 24 (7 ULiège)
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See detailUsing seismic targets as benchmarks for spectroscopic analyses of cool stars
Morel, Thierry ULiege; Miglio, Andrea ULiege; Valentini, Marica ULiege

in Journal of Physics: Conference Series (2011), 328

The frequency of maximum oscillation power measured in dwarfs and giants exhibiting solar-like pulsations provides a precise, and potentially accurate, inference of the stellar surface gravity. An ... [more ▼]

The frequency of maximum oscillation power measured in dwarfs and giants exhibiting solar-like pulsations provides a precise, and potentially accurate, inference of the stellar surface gravity. An extensive comparison for about 40 well-studied pulsating stars with gravities derived by traditional means (ionization balance, pressure-sensitive spectral features or location with respect to evolutionary tracks) supports the validity of this technique and reveals an overall remarkable agreement with mean differences not exceeding 0.05 dex (although with a dispersion of up to ~0.2 dex). It is argued that interpolation in theoretical isochrones may be the most precise way of estimating the gravity by traditional means in nearby dwarfs. The use of seismic targets as benchmarks in the context of forthcoming large-scale surveys (such as the follow up of the Gaia mission) is briefly discussed. [less ▲]

Detailed reference viewed: 15 (0 ULiège)
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See detailUsing sets of behavioral biomarkers to assess short-term effects of pesticide: a study case with endosulfan on frog tadpoles
Denoël, Mathieu ULiege; D'hooghe, Bastien; Ficetola, G. Francesco et al

in Ecotoxicology (2012), 21(4), 1240-1250

Pesticides and other chemicals often have detrimental effects at environmental concentrations. Many amphibian species are particularly threatened because of their susceptibility but also because wetlands ... [more ▼]

Pesticides and other chemicals often have detrimental effects at environmental concentrations. Many amphibian species are particularly threatened because of their susceptibility but also because wetlands are often polluted. Behavioral assessments of toxicity have the advantage of showing sublethal effects but quantitative measures at varied scales of integrations are rarely considered together. In this study, we aimed at showing that these behavioral endpoints could be differently affected across time and concentrations, and be biomarkers of toxicity. To this end, we tested the effects of an organochlorine pesticide (endosulfan) on amphibians during a standard 96 h test. We evaluated possible lag effects in continuing the analyses after removal of the pesticide. The study was based on 240 tadpoles (4 pesticide treatments: 0.4, 3, 22, and 282 lg/l, 1 control and 1 solvent-control). Abnormal behaviors such as lying and swirling rapidly were exhibited only in the presence of the pesticide. Essential functions such as breathing and feeding were deeply affected by the pesticide: contaminated tadpoles breathed and fed less than control tadpoles. They also moved less and occupied a more central position in the aquariums in the presence of the pesticide. A higher mortality was only found at the highest concentration. These results suggest that endosulfan is toxic to amphibians at environmental concentrations. Behavioral markers showed potential as early warning systems. They should thus be used in complement to other markers to detect sublethal effects only a few days after application of the pesticide and at concentrations where mortality does not occur. [less ▲]

Detailed reference viewed: 154 (24 ULiège)
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See detailUsing shear strain localisation to model the fracturing around gallery in unsaturated Callovo-Oxfordian claystone
Pardoen, Benoît ULiege; Levasseur, Séverine ULiege; Collin, Frédéric ULiege

in Chau, Kam Tim; Zhao, Jidong (Eds.) Bifurcation and Degradation of Geomaterials in the New Millennium (2015, January 28)

Galleries drilling leads to damage propagation, fracturing and properties modifications in the surrounding medium. The prediction of the damaged zone behaviour is an important matter and needs to be ... [more ▼]

Galleries drilling leads to damage propagation, fracturing and properties modifications in the surrounding medium. The prediction of the damaged zone behaviour is an important matter and needs to be properly assessed. To do so the fractures can be modelled using shear strain localisation. The coupled local second gradient model is used under unsaturated conditions to correctly model the strain localisation behaviour. The permeability evolution and the rock desaturation due to air ventilation in galleries are considered. Finally, a hydro-mechanical modelling of a gallery excavation in Callovo-Oxfordian claystone is performed leading to a fairly good representation of the damaged zone. [less ▲]

Detailed reference viewed: 71 (32 ULiège)