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See detailIntervention ergonomique à visée cognitive pour le maintien au travail de patients atteints de sclérose en plaques : construction d’une méthodologie et validation d’un questionnaire
Blavier, Adelaïde ULg; Monisse, Aurélié; DELRUE, Gaël ULg et al

in Van de Leemput, Cécile (Ed.) Activités humaines, Technologies et Bien-être (2013, July 11)

The purpose of this paper is to present the construction of a questionnaire in order to evaluate the specific work difficulties and compensation mechanisms developed by multiple sclerosis patients (MS ... [more ▼]

The purpose of this paper is to present the construction of a questionnaire in order to evaluate the specific work difficulties and compensation mechanisms developed by multiple sclerosis patients (MS). At the moment, it does not exist any questionnaire that links the patients cognitive deficits with their professional situation. This lack of accurate assessment is detrimental to the patients job retention. Our questionnaire was constructed from review of literature and interviews of patients and experts. Three groups of patients answered the questionnaire: MS patients, diabetics patients and a control group. We controlled the effect of anxiety and depression and we conducted a factorial analysis that showed the existence of 3 factors: the ergonomics factor (that includes cognitive difficulties and resources and adaptation process), the description of work situation and the social support. The three groups of participants obtained similar results for the work description and the social support while the group of patients with MS obtained a higher score than the other 2 groups for the ergonomics factor. These results suggest that our questionnaire is specific to the MS patients population and to their difficulties they met in their work situations. These results offered also some ways to increase job retention in MS patients population. [less ▲]

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See detailVerification of a novel material model to predict damage in composite structures
Chiu, Louis N.S.; Falzon, Brian G.; Boman, Romain ULg et al

in International Conference on Structural Integrity and Fracture (2013, July 11)

An intralaminar damage model (IDM), based on continuum damage mechanics, was developed for the simulation of composite structures subjected to damaging loads. This model can capture the complex ... [more ▼]

An intralaminar damage model (IDM), based on continuum damage mechanics, was developed for the simulation of composite structures subjected to damaging loads. This model can capture the complex intralaminar damage mechanisms, accounting for mode interactions, and delaminations. Its development is driven by a requirement for reliable crush simulations to design composite structures with a high specific energy absorption. This IDM was implemented as a user subroutine within the commercial finite element package, Abaqus/Explicit[1]. In this paper, the validation of the IDM is presented using two test cases. Firstly, the IDM is benchmarked against published data for a blunt notched specimen under uniaxial tensile loading, comparing the failure strength as well as showing the damage. Secondly, the crush response of a set of tulip-triggered composite cylinders was obtained experimentally. The crush loading and the associated energy of the specimen is compared with the FE model prediction. These test cases show that the developed IDM is able to capture the structural response with satisfactory accuracy. [less ▲]

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See detailDry galloping on bridge cables: roughness and shape effects on an inclined circular cylinder
Benidir, Adel; Flamand, Olivier; Gaillet, Laurent et al

in Proceedings of the European-African Conference on Wind Engineering 2013 (2013, July 09)

Dry galloping of stays in cable-stayed bridges is a phenomenon that is still of interest to the scientific community. Over the course of the current three-year research project numerous experiments will ... [more ▼]

Dry galloping of stays in cable-stayed bridges is a phenomenon that is still of interest to the scientific community. Over the course of the current three-year research project numerous experiments will be carried out to investigate the effect of turbulence and inclination angle on dry galloping. The novel aspect of this study consists of an in-depth investigation into the effect of non uniformity of the pipe surrounding the stay cables on the dry galloping excitation mechanism. Previous studies reported that dry galloping is caused by the appearance of a negative pressure bubble on one side of the circular cylinder at the critical Reynolds number range, leading to a rapid drop in the drag coefficient and the appearance of a non negligible lift force. This paper presents results from initial experiments in the wind tunnel at CSTB – Nantes, France. [less ▲]

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See detailUncoupled spectral analysis with non-proportional damping
Canor, Thomas ULg; Blaise, Nicolas ULg; Denoël, Vincent ULg

in Proceedings of the European-African Conference on Wind Engineering (2013, July 07)

The use of normal modes of vibration in the analysis of structures with non-proportional damping reduces the number of governing equations, but does not decouple them. A common practice consists in ... [more ▼]

The use of normal modes of vibration in the analysis of structures with non-proportional damping reduces the number of governing equations, but does not decouple them. A common practice consists in decoupling the equations by disregarding the off-diagonal elements of the modal damping matrix. This paper proposes a method based on the asymptotic expansion of the modal transfer matrix to take into account the modal coupling in Gaussian spectral analysis. First, the mathematical background is introduced, then the relevance of the method is illustrated within the context of the analysis of a large and real structure submitted to wind loadings. [less ▲]

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See detailPrincipal static wind loads
Blaise, Nicolas ULg; Denoël, Vincent ULg

in 6th Proceedings of European-African Conference on Wind Engineering (2013, July 07)

The concept of static wind load is widely used in practice for structural wind design. In this context, this paper assesses the envelope reconstruction problem stated as follows: find the best set of ... [more ▼]

The concept of static wind load is widely used in practice for structural wind design. In this context, this paper assesses the envelope reconstruction problem stated as follows: find the best set of static loadings that is optimum to reproduce by static analyses, the envelope values of structural responses resulting from a formal buffeting dynamic analysis. A solution was recently derived by means of Principal Static Wind Loads which are well-suited for this problem. The concept is illustrated with a large stadium roof and the accuracy of the envelope reconstruction is analysed. [less ▲]

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See detail3D Modeling of Thin Resistive Sheets in the Discontinuous Galerkin Method for Transient Scattering Analysis
Boubekeur, Mohamed; Kameni, Abelin; Bernard, Laurent et al

in Proceedings of the 19th Conference on the Computation of Electromagnetic Fields (COMPUMAG 2013) (2013, July 03)

This papers presents a modeling of thin resistive sheets. An interface condition is used to avoid the fine mesh. The electromagnetic fields are computed with a time domain Discontinuous Galerkin method in ... [more ▼]

This papers presents a modeling of thin resistive sheets. An interface condition is used to avoid the fine mesh. The electromagnetic fields are computed with a time domain Discontinuous Galerkin method in order to evaluate the shielding effectiveness. A 3D cavity is treated to illustrate the efficiency of the condition. [less ▲]

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See detailLes facteurs de la relation d’agence en niveaux dans la longue chaîne Bailleurs de fonds étrangers - ONG internationales – ONG locales - associations endogènes - bénéficiaires : cas du Burundi
Manirambona, Célestin ULg

in EMES-SOCENT Conference selected papers (2013, July 02)

Several studies on the sources of funding for local NGOs in Africa highlight their dependence on foreign donors, while in developed countries, these organizations have multiple resources. Investigations ... [more ▼]

Several studies on the sources of funding for local NGOs in Africa highlight their dependence on foreign donors, while in developed countries, these organizations have multiple resources. Investigations previously done show that the majority of resources of local NGOs come from foreign donors, and most of them are dead at inception due to lack of funding. Before reaching the beneficiaries, financing goes through several players who are related by an explicit contract: Foreign donors - International NGOs - Local NGOs - Endogenous groups - beneficiaries populations. The literature points to the existence of a contractual relationship between the one who runs the activities and the one that funds them. Yet despite this explicit contract, some actors in this chain of relationships are influenced by other factors and / or their interests and make decisions that have no direct links with the mission of the organization. This leads us to ask ourselves two questions: first, the question about the factors that characterize the relationship between actors and secondly whether at all levels, the actors involve other stakeholders. The present paper aims to provide a conceptual and theoretical framework to characterize the agency chain relationship between these different actors. Although there are studies on the application of the agency theory in the governance of Nonprofit organizations, there have been very few studies done on the agency chain relationship between these organizations. It is then necessary to make new theoretical developments on how local NGOs in Africa in general, and Burundi in particular, are funded and governed; and that, in the case where the actors in the chain relationship are in different contexts. To do this, we will first mobilize and apply the agence theory and others theories of governance at this agency chain relationship. We conclude by showing the peculiarity of Africa in general, and Burundi in particular with additional elements that enhance this agency relationship, making then the conceptual model complex. [less ▲]

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See detailDirect determination of physical parameters for main sequence stars
Rabus, Markus; Lachaume, Regis; Brahm, Rafael et al

in Protostars and Planets VI (2013, July 01)

The environment of planetary formation and evolution is mainly characterized by its host star's physical properties. Until recently most fundamental stellar parameters, like e. g. the star's radius and ... [more ▼]

The environment of planetary formation and evolution is mainly characterized by its host star's physical properties. Until recently most fundamental stellar parameters, like e. g. the star's radius and effective temperature, have only been estimated indirectly; but with advances in interferometric observing technique it is now possible to obtain a direct estimate of them. In this poster we present preliminary results from measured interferometric fringe visibilities of main-sequence stars. These visibilities were collected using the four-beam combiner VLTI/PIONIER instrument and the 1.8m Auxiliary Telescopes (ATs) in A1-G1-K0-J3 quadruplet configuration. We bracketed each science target with different calibrators to ensure reducing the systematic errors in our data. For each target star, the data reduction was performed several hundred times, each time randomizing the set of fringes by the bootstrap method and the calibrators' diameters. This allowed us to take into account error correlations across spectral channels, between consecutive observations, and overnight. Each result was least-squares fitted by a uniform disc, yielding a value for the target's diameter. From the distribution of diameters we assessed the statistical error in the respective measurement. Using the HIPPARCOS parallax we estimated the distance and obtained the star's linear radius. Combined with the bolometric flux we obtained a direct quantification of the effective temperature from the Stefan-Boltzmann equation. Finally, these direct determinations of stellar radii and effective temperatures enable us to better characterize planets around main-sequence stars. [less ▲]

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See detailUnraveling the mystery of exozodiacal dust
Ertel, Steve; Augereau, Jean-Charles; Thebault, Philippe et al

in Protostars and Planets VI (2013, July 01)

Exozodiacal dust clouds are thought to be the extrasolar analogs of the Solar System's zodiacal dust. Studying these systems provides insights in the architecture of the innermost regions of planetary ... [more ▼]

Exozodiacal dust clouds are thought to be the extrasolar analogs of the Solar System's zodiacal dust. Studying these systems provides insights in the architecture of the innermost regions of planetary systems, including the habitable zone. Furthermore, the mere presence of the dust may result in major obstacles for direct imaging of earth-like planets. Our EXOZODI project aims to detect and study exozodiacal dust and to explain its origin. We are carrying out the first large, near-infrared interferometric survey in the northern (CHARA/FLUOR) and southern (VLTI/PIONIER) hemisphere. Preliminary results suggest a detection rate of up to 30% around A to K type stars and interesting trends with spectral type and age. In addition to the statistical analysis of our survey results, detailed modeling studies of single systems, modeling of possible dust creation mechanisms and the development of next-generation modeling tools dedicated to address the mystery of exozodiacal dust are main tasks of our project. [less ▲]

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See detailThe VLTI/PIONIER survey of southern TTauri disks.
Anthonioz, Fabien; Ménard, Francois; Pinte, Christophe et al

in Protostars and Planets VI (2013, July 01)

Studying the inner regions of protoplanetary disks (1-10 AU) is of importance to understand the formation of planets and the accretion process feeding the forming central star. Herbig AeBe stars are ... [more ▼]

Studying the inner regions of protoplanetary disks (1-10 AU) is of importance to understand the formation of planets and the accretion process feeding the forming central star. Herbig AeBe stars are bright enough to be routinely observed by Near IR interferometers. The data for the fainter T Tauri stars is much more sparse. In this contribution we present the results of our ongoing survey at the VLTI. We used the PIONIER combiner that allows the simultaneous use of 4 telescopes, yielding 6 baselines and 3 independent closure phases at once. PIONIER's integrated optics technology makes it a sensitive instrument. We have observed 22 T Tauri stars so far, the largest survey for T Tauri stars to this date. Our results demonstrate the very significant contribution of an extended component to the interferometric signal. The extended component is different from source to source and the data, with several baselines, offer a way to improve our knowledge of the disk geometry and/or composition.These results validate an earlier study by Pinte et al. 2008 and show that the dust inner radii of T Tauri disks now appear to be in better agreement with the expected position of the dust sublimation radius, contrary to previous claims. [less ▲]

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See detailYield variability linked to climate uncertainty and nitrogen fertilisation
Dumont, Benjamin ULg; Basso, Bruno; Leemans, Vincent ULg et al

in Stafford, John V. (Ed.) Precision agriculture '13 (2013, July)

At the parcel scale, crop models such as STICS are powerful tools to study the effects of variable inputs such as management practices (e.g. nitrogen (N) fertilisation). In combination with a weather ... [more ▼]

At the parcel scale, crop models such as STICS are powerful tools to study the effects of variable inputs such as management practices (e.g. nitrogen (N) fertilisation). In combination with a weather generator, we built up a general methodology that allows studying the yield variability linked to climate uncertainty, in order to assess the best N practice. Our study highlighted that, applying the Belgian farmer current N practice (60 60 60 kgN.ha-1), the yield distribution was found to be very asymmetric with a skewness of -1.02 and a difference of 5% between the mean (10.5 t.ha-1) and the median (11.05 t.ha-1) of the distribution. Which implied that, under such practice, the probability for farmers to achieve decent yields, in comparison of the mean of the distribution, was the highest. [less ▲]

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See detailNonlinear Computational Homogenization Method for the Evaluation of Eddy Currents in Soft Magnetic Composites
Niyonzima, Innocent ULg; Sabariego, Ruth Vazquez; Dular, Patrick ULg et al

in Proceedings of the 19th Conference on the Computation of Electromagnetic Fields (COMPUMAG2013) (2013, July)

In this paper, a heterogeneous multiscale method (HMM) technique is applied to model the behaviour of electromagnetic fields in soft magnetic composites (SMC). Two problems are derived from the two-scale ... [more ▼]

In this paper, a heterogeneous multiscale method (HMM) technique is applied to model the behaviour of electromagnetic fields in soft magnetic composites (SMC). Two problems are derived from the two-scale homogenization theory: a macroscale problem that captures the slow variations of the overall solution, and many mesoscale problems that allow determining the constitutive laws at the macroscale. As application, an SMC core is considered. [less ▲]

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See detailA multirate approach to combine electromagnetic transients and fundamental-frequency simulations
Plumier, Frédéric ULg; Geuzaine, Christophe ULg; Van Cutsem, Thierry ULg

in Proc. 10th International Conference on Power System Transients (2013, July)

Abstract--- A new multi-rate technique is proposed to combine fundamental-frequency simulation (typical of stability studies) with electromagnetic transients simulation. The objective of this hybrid ... [more ▼]

Abstract--- A new multi-rate technique is proposed to combine fundamental-frequency simulation (typical of stability studies) with electromagnetic transients simulation. The objective of this hybrid approach is to obtain more accurate simulations than with the fundamental-frequency approximation, while saving computing time by applying the detailed model to a subsystem only, in some neighbourhood of the disturbance. It also allows to remove some limitations of fundamental-frequency simulation, such as the difficulty of simulating unbalanced faults. A relaxation technique is used to iterate between both models with simple interfacing. Preliminary results obtained with a 74-bus test system are presented, together with a comparison with full electromagnetic transients simulation. [less ▲]

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See detailPrediction of non-linear time-variant dynamic crop model using bayesian methods
Mansouri, Majdi ULg; Dumont, Benjamin ULg; Destain, Marie-France ULg

in John Stafford (Ed.) Precision agriculture '13 (2013, July)

This work addresses the problem of predicting a non-linear time-variant leaf area index and soil moisture model (LSM) using state estimation. These techniques include the extended Kalman filter (EKF ... [more ▼]

This work addresses the problem of predicting a non-linear time-variant leaf area index and soil moisture model (LSM) using state estimation. These techniques include the extended Kalman filter (EKF), particle filter (PF) and the more recently developed technique, variational filter (VF). In the comparative study, the state variables (the leaf-area index LAI, the volumetric water content of the layer 1, HUR1 and the volumetric water content of the layer 2, HUR2) are estimated from noisy measurements of these variables, and the various estimation techniques are compared by computing the estimation root mean square error with respect to the noise-free data. The results show that VF provides a significant improvement over EKF and PF. [less ▲]

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See detailMultiple Viewpoints on Landscape Quality Assessment: some evidence from a survey in Wallonia and Romania
Schmitz, Serge ULg; Vanderheyden, Vincent ULg; Teleuca, Alexandra et al

in Morimoto, Takehiro; Ichikawa, Yasuo; Kim, Doo-Chul (Eds.) Globalization and New Challenges of Agricultural and Rural Systems (2013, July)

Actually assessing landscapes out of a specific framework is not an easy task due to the multiple functions that landscapes perform.The paper presents the result of a survey among landscape experts in ... [more ▼]

Actually assessing landscapes out of a specific framework is not an easy task due to the multiple functions that landscapes perform.The paper presents the result of a survey among landscape experts in Romania and Wallonia. Expert had to specify their level of agreement on 52 Likert items regarding landscape quality indicators [less ▲]

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See detailPoroelastic Center of Dilation Revisited
Huynen, Alexandre ULg; Detournay, Emmanuel

in Hellmich, Christian; Pichler, Bernhard; Dietmar, Adam (Eds.) Poromechanics V: Proceedings of the Fifth Biot Conference on Poromechanics (2013, July)

A comparison of the original elastic solution for the center of dilation with the classic Lame ́ solution reveals an unexpected dependence of the center of dilation solu- tion on Poisson’s ratio. This ... [more ▼]

A comparison of the original elastic solution for the center of dilation with the classic Lame ́ solution reveals an unexpected dependence of the center of dilation solu- tion on Poisson’s ratio. This inconsistency is investigated by means of two alternative representations of the singularity which lead to the identification of a compressed zone inside the singularity. The poroelastic equivalent to this nucleus of strain is shown to be the superposition of the elastic one with drained material parameters and an instan- taneous point fluid source associated with a finite volume of fluid that is expelled from the compressed region inside the singularity and is injected in the porous medium. [less ▲]

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See detailContributions to the process modelling of resin infusion under flexible tooling (RIFT) manufacturing for composite aerostructures
Pierce, R.S.; Falzon, B.G.; Thompson, M.C. et al

in Proceedings of ICCM19 (2013, July)

The cost of manufacturing textile-reinforced composite aerostructures using Resin Infusion under Flexible Tooling (RIFT) can be reduced by computational modelling. This paper outlines the current progress ... [more ▼]

The cost of manufacturing textile-reinforced composite aerostructures using Resin Infusion under Flexible Tooling (RIFT) can be reduced by computational modelling. This paper outlines the current progress and contributions made towards this goal. A continuum-based material model was incorporated into a finite element package to simulate the draping of a dry carbon fibre fabric. It accurately tracks the changes in the warp and weft fibre orientations and has been experimentally validated. Material characterisation was performed to determine the tensile and shear properties of a plain weave fabric reinforcement material. In support of bias extension shear testing, an accessible Digital Image Correlation (DIC) approach was developed for accurate optical strain measurement. A relationship between permeability and shear angle was also experimentally determined using a novel permeability measurement technique. Future work is planned to combine all these aspects in an infusion model and demonstrate the complete process model. [less ▲]

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See detailIdentification of mechanical systems with local nonlinearities through discrete-time Volterra series and Kautz functions
Shiki, Sidney Bruce; Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg et al

in Proceedings of the 11th International Conference on Recent Advances in Structural Dynamics (2013, July)

Mathematical modeling of mechanical structures is an important research area in structural dynamics. One of the goals of this area is to obtain a model that accurately predicts the dynamics of the system ... [more ▼]

Mathematical modeling of mechanical structures is an important research area in structural dynamics. One of the goals of this area is to obtain a model that accurately predicts the dynamics of the system. However, the nonlinear eff ects caused by large displacements and boundary conditions like gap, backlash or joint are not as well understood as the linear counterpart. This paper identifies a non-parametric discrete-time Volterra model of a benchmark nonlinear structure consisting of a cantilever beam connected to a thin beam at its free end. Time-domain data experimentally measured are used to identify the Volterra kernels, which are expanded with orthogonal Kautz functions to facilitate the identification process. The nonlinear parameters are then estimated through a model updating process involving optimization of the residue between the numerical and experimental kernels. The advantages and drawbacks of the Volterra series for modeling the behavior of nonlinear structures are finally indicated with suggestions to overcome the disadvantages found during the tests. [less ▲]

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See detailEquivalent static wind loads for structures with non-proportional damping
Blaise, Nicolas ULg; Canor, Thomas ULg; Denoël, Vincent ULg

in Proceedings of the 11th International Conference on Recent Advances in Structural dynamics (2013, July)

In current practice, wind structural design is often carried out using the concept of equivalent static wind loads. The main characteristic of such loadings is to reproduce, with static analyses, the same ... [more ▼]

In current practice, wind structural design is often carried out using the concept of equivalent static wind loads. The main characteristic of such loadings is to reproduce, with static analyses, the same extreme structural responses as those resulting from a formal buffeting analysis. This paper proposes a method for the computation of equivalent static wind loads for structures with slight non-proportional damping in a modal framework. Because of the smallness of the out-of diagonal terms, this method is based on recent developments related to asymptotic expansion of the modal transfer matrix of such structures. As a main benefit, the static loading is described as a perturbation of the equivalent loading that would be obtained for the uncoupled system. The main contribution of this paper is to formalize the expression of the correction terms resulting from the non-proportionality of damping. The method is presented with a detailed illustrative example. [less ▲]

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See detailInfluence des communications sur la construction du common ground. Proposition d'une méthodologie d'analyse de la dynamique temporelle des échanges multimodaux.
Defays, Aurore ULg; Leclercq, Pierre ULg; Nyssen, Anne-Sophie ULg

in van de Leemput, Cécile; Chauvin, Christine; Hellemans, Catherine (Eds.) Activités humaines, Technologies et Bien-être (EPIQUE 2013) (2013, July)

L’objectif de cette étude est de présenter une méthodologie d’analyse des communications multimodales dans les situations de conception collective. Cette méthodologie permet de décrire quelles sont les ... [more ▼]

L’objectif de cette étude est de présenter une méthodologie d’analyse des communications multimodales dans les situations de conception collective. Cette méthodologie permet de décrire quelles sont les modalités de communication qui supportent particulièrement l’élaboration du common ground, zone de partage indispensable pour l’efficacité de la communication, et donc pour la performance collaborative. La méthode présentée vise également à pouvoir identifier les articulations pertinentes entre modalités de communication, dans le sens où elles favorisent l’élaboration de ce processus. Dans une première phase de notre recherche, nous avons observé et analysé les échanges multimodaux tels qu’ils prennent place en situation « naturelle » (ou non-médiatisée) dans le but de prétester notre méthode, mais également de pouvoir comparer cette situation avec les situations de collaboration distantes et outillées par des nouvelles technologies que nous envisagerons par la suite. [less ▲]

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See detailNumerical and Experimental Investigation of Slot-Blowing Air Over a Cylinder
Runge, William; Buysschaert, Frank; Hayez, Jules et al

in Proceedings of the 5th European Conference for Aeronautics and Space Sciences (2013, July)

Tangential slot blowing around a cylinder in the Coanda effect has been proposed as a mechanism for yaw control in a novel coaxial helicopter. The proposed design has been investigated computationally ... [more ▼]

Tangential slot blowing around a cylinder in the Coanda effect has been proposed as a mechanism for yaw control in a novel coaxial helicopter. The proposed design has been investigated computationally, using the unsteady k-ω SST solver in NUMECA, as well as experimentally in the wind tunnel at the Université de Liège. While the concept in general is promising, it has been shown that there are some potential problems, including pitch-yaw coupling and some unsteady flow conditions. These problems exist under varied circumstances, and, exist at least in part due to the complicated flow-field in this problem, even in 2-dimensions. [less ▲]

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See detailUsing Proper Orthogonal Decomposition and Dynamic Mode Decomposition Methods for Comparing CFD Results Experimental Measurements
Guissart, Amandine ULg; Andrianne, Thomas ULg; Dimitriadis, Grigorios ULg et al

in Proceedings of the 16th 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 ▲]

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See detailAeroelastic response of a 2-DOF wing with structural and aerodynamic nonlinearity
Norizham, Abdul Razak ULg; Dimitriadis, Grigorios ULg

in Proceedings of the International Forum on Aeroelasticity and Structural Dynamics, IFASD 2013 (2013, June 25)

The aeroelastic behaviour of a wing oscillating in the heave and pitch degrees of freedom with continuos nonlinear stiffness is examined by means of wind tunnel experiments. The phenomena of interest are ... [more ▼]

The aeroelastic behaviour of a wing oscillating in the heave and pitch degrees of freedom with continuos nonlinear stiffness is examined by means of wind tunnel experiments. The phenomena of interest are classical flutter and limit cycle oscillation. The focus of the present work is the transformation of classical flutter into LCOs by varying the stiffness from linear to nonlinear stiffness. The interaction of flow separation-related nonlinearity with structural nonlinearities is also of interest. The measured aeroelastic responses are analyzed and the bifurcation behavior of the dynamic system is characterized. The analysis shows that the bifurcation behaviour is dictated neither by the structural nor from the aerodynamic nonlinearity but by a combination of the two. [less ▲]

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See detailIs the wheat distillers grains soluble ProtiWanze a valuable alternative to soybean and canola meals in beef cattle diet?
Lessire, Françoise ULg; Rollin, Frédéric ULg

in ICPD (Ed.) Book of Abstracts (2013, June 24)

The objective of this study was to evaluate whether introducing the condensed wheat distillers soluble ProtiWanze® (PW) in diets of beef cattle has an impact on feeding costs, health and production of the ... [more ▼]

The objective of this study was to evaluate whether introducing the condensed wheat distillers soluble ProtiWanze® (PW) in diets of beef cattle has an impact on feeding costs, health and production of the animals. PW by-product from a Belgian bio-ethanol plant which utilized only wheat without bran, is an acid (pH=4) liquid feed rich in energy (VEM= 1130) and protein (TP= 282 mg/kg DM). PW supplementation from 9 to 13% on DM basis has been tested in 4 suckler cows’ farms for 4 months in 2011 and 2012. In 2011, 2 BB (H1 and H3) and 1 Blonde d’Aquitaine (H2: 23 cows) herds were evaluated and in 2012, the Blonde d’Aquitaine herd was replaced by a third BBB herd (H4: 42 cows). Every month, animals’ health and production were checked by the mean of Body Condition Score, Ruminal Fill, Fecal Consistency, Undigested Fraction and Locomotion Scores determination, as described by Zaaier et al.(2001) and Sprecher et al.(1997). Ruminal fluid was sampled by a stomach tube (Ruminator®) on 5 cows for pH, redox potential (Methylene blue test) and protozoa assessment (optical microscopy). Reproduction performances of this 2 year’s-period were analyzed. Price of a diet containing the same amount of proteins brought by a mixture of 1/3 soybean and 2/3 canola meal was calculated to verify whether introducing PW reduced feeding costs. Whatever the concentration of PW used, no adverse effect has been observed concerning reproduction, production performance, ruminal pH. Feeding costs were reduced by 0.08 €/cow/day in 2011 and by 0.02 €/cow/day in 2012. This lower spared amount in 2012 is the consequence of the reduction in PW protein concentration while its price increased. Anyway, comparison has to take into account the energy brought by this CDS as it has been suggested by Petersen’s equation, which compares CDS price with soybean meal but also with maize price. Further argument to be considered, especially in BB, is the high PW palatability, its low ruminal filling value and better roughage digestion. [less ▲]

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See detailSimulation of bird wing flapping using the unsteady vortex lattice method
Gardiner, James; Norizham, Abdul Razak ULg; Dimitriadis, Grigorios ULg et al

in Proceedings of the International Forum on Aeroelasticity and Structural Dynamics, IFASD 2013 (2013, June 24)

The flight of barnacle geese at airspeeds representing high-speed migrating flight is investigated using experiments and simulations. The experimental part of the work involved the filming of three ... [more ▼]

The flight of barnacle geese at airspeeds representing high-speed migrating flight is investigated using experiments and simulations. The experimental part of the work involved the filming of three barnacle geese flying at different airspeeds in a wind tunnel. The video footage was analysed in order to extract the wing kinematics. Additional information, such as wing geometry and camber was obtained from a 3D scan of a dried wing. An unsteady vortex lattice method was used to simulate the aerodynamics of the measured flapping motion. It was found that the simulation correctly predicted the shape of the wake and the fact that the wing is aerodynamically inactive during the upstroke. The predicted aerodynamic lift and thrust forces were very sensitive to the wing's camber. Future work will attempt to identify the sensitivity to all the wing shape and kinematic parameters. Additional phenomena will also be modelled, including passive twisting of the wingtip, body lift and leading edge suction. [less ▲]

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See detailHemoreactivity of polymeric carriers designed for drug delivery systems
Grandfils, Christian ULg; Sevrin, Chantal ULg

in Proceeding Biomedica 2013 (2013, June 19)

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See detailIMPLEMENTATION OF A WEAK COUPLING APPROACH BETWEEN A CFD AND AN FE SOFTWARE FOR FIRES IN COMPARTMENT
Tondini, Nicola; Franssen, Jean-Marc ULg

in Idelsohn, S; Papadrakakis, M; Schrefler, B (Eds.) V International Conference on Computational Methods for Coupled Problems in Science and Engineering (2013, June 17)

The paper presents the assumptions and the issues that arise when developing an integrated modelling methodology between a Computational Fluid Dynamics (CFD) software applied to compartment fires and a ... [more ▼]

The paper presents the assumptions and the issues that arise when developing an integrated modelling methodology between a Computational Fluid Dynamics (CFD) software applied to compartment fires and a Finite Element (FE) software applied to structural systems subjected to fire. In particular, a weak coupling approach used to simulate a fire exposed structure by modelling the fire development in the compartment, the heat penetration in the structure and the mechanical response is described. The advantages and the disadvantages of such a technique are highlighted compared to a full coupling that conversely takes into account all mutual interactions. The favourable aspect of computing the thermal response of the structure in the FE model in order to avoid modelling the structure in the CFD model is underlined, namely a sensitive reduction of computational demand. Finally, the study is enriched by an application of this methodology that concerns the simulation of a pool fire in an open compartment the results of which are compared with those obtained by employing the simplified Hasemi model included in the Eurocodes. [less ▲]

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See detailChemically resistant encapsulant to enable a novel MEMS fabrication process
Stoukatch, Serguei ULg; Walewyns, Thomas; Tooten, Ester et al

in Conf. Proceedings (2013, June 13)

We have proposed and demonstrated a novel sequence in MEMS fabrication process flow. The novel MEMS fabrication process flow can be shortly described as a “packaging first, MEMS release second”, whereas a ... [more ▼]

We have proposed and demonstrated a novel sequence in MEMS fabrication process flow. The novel MEMS fabrication process flow can be shortly described as a “packaging first, MEMS release second”, whereas a standard process starts form MEMS release and ends up with packaging. The process is explored on a 3D capacitive MEMS sensor (3 x 3 mm²). Unreleased wafer is singulated by sawing on individual dies, then the individual sensor is mounted to the package, wire bonded and encapsulated. Because the sensors are still unreleased there is no damage occurred during the assembly. However the choice for the encapsulant material is not evident. The encapsulant must survive the chemical attack during the MEMS release process (mixture of 73%HF and IPA (isopropanol)), followed by a triple rinse in IPA. We pre-selected 6 different encapsulants: a silicone-, an epoxy- and an urethane-based. At least one encapsulant passed the acceptance criteria: there is no delamination, there is no texture change and the encapsulant maintains a sufficient mechanical adhesion. Additionally to that we measured micro-hardness of the encapsulant before and after the HF release test. We also performed an electrical characterization of the flow meter sensor before and after the HF release and we detected no changes in the sensor’s performance caused by HF exposure. We have proposed and demonstrated a novel sequence for MEMS fabrication. We packaged the sensor first, and performed the release after that. The key enabler for the novel process is the encapsulant which can withstand exposure to the release solution (73%HF:IPA). [less ▲]

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See detailDYNAMIC LINE RATING AND AMPACITY FORECASTING AS THE KEYS TO OPTIMISE POWER LINE ASSETS WITH THE INTEGRATION OF RES. THE EUROPEAN PROJECT TWENTIES DEMONSTRATION INSIDE CENTRAL WESTERN EUROPE
Nguyen, Huu-Minh ULg; Schell, Peter; Lilien, Jean-Louis ULg

in Proceedings of Congrès International des Réseaux Electriques de Distribution (2013, June 12)

The general increase of Distributed & intermittent renewable Generation is pushing TSOs and DSOs to find innovative solutions to increase the capacity of their networks. Dynamic Line Rating (DLR) has ... [more ▼]

The general increase of Distributed & intermittent renewable Generation is pushing TSOs and DSOs to find innovative solutions to increase the capacity of their networks. Dynamic Line Rating (DLR) has proven to be a very promising solution to cope with this issue. However, few experiments so far have addressed ampacity forecasting, which is critical to allow the integration of DLR in the electricity market processes. To tackle this gap, we developed an algorithm based on real-time DLR measurements and weather forecasts, which provides ampacity forecasts up to two days ahead. This paper describes the results of the EU-funded TWENTIES Demo led in Belgium on two 150kV lines. Currently, the DLR system used provides a two-day ahead ampacity forecast with more than 10% average gain over static rating (dynamic gain forecast varying roughly between 0% and 30%) with 98% confidence. Operational gains allowed by this increase of flexibility are still being assessed. [less ▲]

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See detailExperimental analysis of the stability of coarse sediments
Duma, Diana ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Symposium on Two-phase Modelling for Sediment Dynamics in Geophysical Flows (2013, June 12)

To predict the inception of sediment motion, Shields diagram remains the most widely used criterion in engineering practice so far. However, this approach faces several limitations and a number of gaps in ... [more ▼]

To predict the inception of sediment motion, Shields diagram remains the most widely used criterion in engineering practice so far. However, this approach faces several limitations and a number of gaps in knowledge still remain. The present research aims to provide new knowledge about the inception of motion in rivers with coarse sediments. A series of experiments was conducted in a flume horizontal 6 m long and 15 cm wide. The bottom was paved, either entirely or partly, with gravels of approximately 12 mm in diameter. Ultrasonic sensors were used to measure the water depth, a flowmeter for the discharge, an ultrasonic velocity profiler (UVP) transducer for the flow velocity. Three different thresholds were defined to distinguish between the following states: no motion, vibration of stones, local motion, and large scale motion. The overwhelming influence of turbulence was emphasized by the conducted tests. This paper details the results of these experiments and demonstrates the need for further research in order to better quantify these effects. [less ▲]

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

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

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See detailA Simplified Procedure to Assess the Strength of a Ship Impacting a Lock Miter Gate
Buldgen, Loïc ULg; Le Sourne, Hervé; Rigo, Philippe ULg

in Proceedings of the ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering (2013, June 09)

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See detailPrédiction des performances sportives et détection précoce des myopathies par respirométrie à haute résolution
Votion, Dominique ULg; Serteyn, Didier ULg

in cheval athlète, stress oxydant & inflammation (2013, June 07)

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See detailOptimization of the operating conditions of an existing biomass CHP plant with respect to pollutants levels
Sartor, Kevin ULg; Restivo, Yannick ULg; Ngendakumana, Philippe ULg et al

in Proceedings of 21st Biomass Conference and Exhibition (2013, June 03)

While small and medium size biomass combined heat and power plants (i.e., up to 5 MW of electrical rated power) represent an attractive option to exploit locally available biomass resources at low cost ... [more ▼]

While small and medium size biomass combined heat and power plants (i.e., up to 5 MW of electrical rated power) represent an attractive option to exploit locally available biomass resources at low cost, the corresponding investment per unit of rated power significantly rises when the installed power decreases. In these cases, secondary pollutant emissions control measures are most of the time not economically viable and primary emissions control must be used alone to avoid the formation of undesired compounds such as $NO_x$ and $SO_x$. Primary control measures require the careful optimization of fuel quality and combustion process. For plant operators, being able to accommodate biomass quality changes in order to minimize the fuel cost can be of great importance in order to guarantee the profitability of the plant. This contribution is dedicated to the development of zero-dimensional (input-output) combustion simulation model able to predict the pollutants emissions resulting from complete and incomplete combustion with respect to varying combustion operation (ambient temperature, humidity, fumes recirculation,..). This tool is intended to be integrated in global simulation model of the CHP plant and the attached district heating network installed on the University campus in Liège. Doing so, the plant operation can be optimized with respect to economic as well as environmental and energetic aspects (3E approach) thus ensuring the sustainability of the approach. [less ▲]

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See detailShip Manoeuvring Behaviour in Crossing Current Near-by a Lock
HASEGAWA, K; OH, K G; Ahmed, Y A et al

in VanTorre, Marc (Ed.) Third International Conference on Ship Manoeuvring in Shallow and Confined Water (2013, June 03)

Ship behaviour in current is one of the classical problems in ship manoeuvrability. However, it is not yet fully investigated. The study is motivated by an assessment study on the ship navigation near by ... [more ▼]

Ship behaviour in current is one of the classical problems in ship manoeuvrability. However, it is not yet fully investigated. The study is motivated by an assessment study on the ship navigation near by a river lock where relatively strong current exists. It is demonstrated how a ship behaves in the current and relatively large drift angle may happen, if the current is comparative to ship speed. In this situation, the hydrodynamic forces and moment acting on a ship is not any more at the range of lift force/moment, and therefore normal mathematical model cannot be applied. Similar situation may occur in case of rapid river stream condition, when a ship losts its power in current. At East Japan Great Earthquake happened in 2011, many ships without their power were drifting in tsunami. It is urgent matter to investigate on the ship behaviour in such situation. [less ▲]

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See detailA PML for convex truncated domains in time-dependent acoustics with a DG-FE discretization
Modave, Axel ULg; Lambrechts, Jonathan; Delhez, Eric ULg et al

in Proceedings of the 11th International Conference on Mathematical and Numerical Aspects of Waves (WAVES 2013) (2013, June 03)

A new perfectly matched layer (PML) is proposed for convex truncated domains in the context of time-dependent acoustics. With this formulation, the size of the computational domain can be reduced when ... [more ▼]

A new perfectly matched layer (PML) is proposed for convex truncated domains in the context of time-dependent acoustics. With this formulation, the size of the computational domain can be reduced when classical shapes of truncated domains are less appropriate. A numerical discretization based on the discontinuous Galerkin method is then described and validated. An example of realistic three-dimensional application is finally proposed. [less ▲]

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See detailAn Observational Study of Mixing in Fast-Rotating Massive Stars: Description of the Method and Very First Results
Morel, Thierry ULg; Palate, Matthieu ULg; Rauw, Grégor ULg

in Massive Stars: From alpha to Omega (2013, June 01)

Collecting He and CNO abundances for a large sample of fast-rotating massive stars is crucial for addressing the efficiency of rotational mixing in these objects. This is becoming a pressing issue ... [more ▼]

Collecting He and CNO abundances for a large sample of fast-rotating massive stars is crucial for addressing the efficiency of rotational mixing in these objects. This is becoming a pressing issue following the recent recognition based on observations by the VLT-FLAMES Survey of massive stars that fast rotators can show no signs of deep mixing contrary to the predictions of models. We have embarked in a project aiming at determining the abundances of the key elements indicators of mixing in a sample of bright, Galactic OB dwarfs. We present here the method and the very first results for two of the fastest OB stars known vsin i = 400 km/s : HD 93521 and zeta Oph. [less ▲]

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See detailMassive Stars in the Gaia-ESO Survey
Blomme, Ronny; Fremat, Yves; Lobel, Alex et al

in Massive Stars: From alpha to Omega (2013, June 01)

The Gaia-ESO Survey (GES) is an ambitious project to study the formation and evolution of the Milky Way and its stellar populations. It is led by Gerry Gilmore and Sofia Randich and includes about 350 Co ... [more ▼]

The Gaia-ESO Survey (GES) is an ambitious project to study the formation and evolution of the Milky Way and its stellar populations. It is led by Gerry Gilmore and Sofia Randich and includes about 350 Co-Investigators. During 300 nights (spread over 5 years) of order 10^5 Giraffe spectra and 10^4 UVES spectra will be taken. As part of the survey, about 13 clusters will be observed that were chosen specifically for their massive-star content. We report on the preliminary analysis of GES data from two such clusters: NGC 3293 and NGC 6705. We determine stellar parameters for the B-type stars in NGC 3293 and compare the A-type stars population between the two clusters. We also use a repeat observation to study binarity and use the radial velocity information to study cluster membership in NGC 3293. We also list our plans for future observations, which include the Carina nebula region. [less ▲]

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See detailSimultaneous X-ray and Optical Variability Study of the O-star Binary delta Orionis with Chandra and MOST
Nichols, Joy; Moffat, Anthony F. J.; Ignace, Richard et al

in Massive Stars: From alpha to Omega (2013, June 01)

We report preliminary results from variability analysis of delta Ori in Chandra high-resolution X-ray spectroscopy and concurrent MOST high-precision optical photometry. With nearly complete phase ... [more ▼]

We report preliminary results from variability analysis of delta Ori in Chandra high-resolution X-ray spectroscopy and concurrent MOST high-precision optical photometry. With nearly complete phase coverage of the 5-day eclipsing binary orbit, it is possible to measure directly radial velocity and flux variations as a function of phase, leading to a mapping of the stellar wind distribution for the massive primary star. The phase dependence of the X-ray overall intensity and the comparative behavior of the emission lines are also presented. [less ▲]

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See detailRecent results on the hierarchical triple system HD 150136
Gosset, Eric ULg; Berger, J. P.; Absil, Olivier ULg et al

in Bonanos, Alceste (Ed.) Massive Stars: From alpha to Omega (2013, June 01)

HD 150136 is a hierarchical triple system, non-thermal radio emitter, made of three O stars totalling some 130 solar masses. The 2.67-day inner orbit is rather well-known. Recent works derived a good ... [more ▼]

HD 150136 is a hierarchical triple system, non-thermal radio emitter, made of three O stars totalling some 130 solar masses. The 2.67-day inner orbit is rather well-known. Recent works derived a good approximation for the outer orbit with a period of 3000 days. We report here on interferometric observations that allow us to angularly resolve the outer orbit. First evidences for an astrometric displacement are given. The determination of the outer system orbit gives access to the inclinations of the systems and to the masses, including the one of the O3-O3.5 primary star. [less ▲]

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See detailThe Nebula around the Luminous Blue Variable WRAY 15-751 as seen by Herschel
Vamvatira-Nakou, Chloi ULg; Hutsemekers, Damien ULg; Royer, P. et al

in Massive Stars: From alpha to Omega (2013, June 01)

To understand the evolution of massive stars it is crucial to study the nebulae associated to Luminous Blue Variables which can reveal the star mass-loss history. We obtained far-infrared Herschel PACS ... [more ▼]

To understand the evolution of massive stars it is crucial to study the nebulae associated to Luminous Blue Variables which can reveal the star mass-loss history. We obtained far-infrared Herschel PACS imaging and spectroscopic observations of the nebula associated with the Luminous Blue Variable star WRAY 15-751. These images revealed a second nebula, bigger and cooler, lying in an empty cavity that probably delineates the remnant of the O-star bubble formed when the star was on the Main Sequence. The dust mass and temperature were derived from the modeling of the far-infrared SED. The analysis of the emission line spectrum revealed that the main nebula consists of a region of photoionised gas surrounded by a thin photodissociation region. Both regions are mixed with dust. The calculated C, N, O abundances, together with the estimated mass-loss rate, show that the nebula was ejected from the star during a Red Supergiant phase. This is compatible with the latest evolutionary tracks for a ~40 Mo star with little rotation. [less ▲]

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See detailUsing mobile milking robots for special quality dairy products based on site specific grazing
Oudshoorn, F.W.; Philipsen, B.; Dufrasne, Isabelle ULg et al

in A Helgadóttir (Ed.) Grassland Science in Europe : The role of Grasslands in a Green Future - Threats and Perspectives in Less Favoured Areas (2013, June)

An option for combining grazing and automatic milking is Infield Automatic Milking, with more or less mobile infield automatic milking systems (IAMS), which have been practiced since 2008 in several ... [more ▼]

An option for combining grazing and automatic milking is Infield Automatic Milking, with more or less mobile infield automatic milking systems (IAMS), which have been practiced since 2008 in several European countries. This emerging technology can be used to harvest milk from specific areas, giving specialized dairies the possibility to market concept milk, cheese or butter. Terroir dairy can be a new way to increase marginal product value and thereby farm income. Three different options are described; i) the IAMS placed on a stationary platform in the field, ii) movable together with facilities necessary for the functionality from field to field, iii) as a self propelled moving unit that changes positions in the field every day, requiring transportation of the milk to the field border. All systems could guarantee dairy products based on maximum grazing for the period the pasture can provide sufficient feeding. Batch size depends on the dairies minimum process volume for the specific products, local conditions will be decisive for the amount of days needed for pooling before production. [less ▲]

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See detailAircraft engine gas path diagnostic methods: public benchmarking results
Simon, Donald; Borguet, Sébastien ULg; Léonard, Olivier ULg et al

in Proceedings of ASME Turbo Expo 2013 (2013, June)

Recent technology reviews have identified the need for objective assessments of aircraft engine health management (EHM) technologies. To help address this issue, a publicly available gas path diagnostic ... [more ▼]

Recent technology reviews have identified the need for objective assessments of aircraft engine health management (EHM) technologies. To help address this issue, a publicly available gas path diagnostic benchmarking problem has been created and made publicly available. This software tool, referred to as the Propulsion Diagnostic Method Evaluation Strategy (ProDiMES), has been constructed based on feedback provided by individuals within the aircraft EHM community. It provides a standard benchmarking problem enabling users to develop, evaluate and compare diagnostic methods. This paper will present an overview of ProDiMES along with a description of four gas path diagnostic methods developed and applied to the problem. These methods, which include analytical and empirical diagnostic techniques, will be described and associated blind test case metric results will be presented and compared. Lessons learned along with recommendations for improving the public benchmarking processes will also be presented and discussed. [less ▲]

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See detailCOORDINATED VOLTAGE CONTROL OF DISTRIBUTION NETWORKS HOSTING DISPERSED GENERATION
Van Cutsem, Thierry ULg; Valverde, Gustavo ULg

in Proc. 22nd International conference on Electricity Distribution (2013, June)

This paper presents a centralized control scheme to regulate distribution network voltages in the presence of dispersed generation. The algorithm resorts to model predictive control to smoothly bring ... [more ▼]

This paper presents a centralized control scheme to regulate distribution network voltages in the presence of dispersed generation. The algorithm resorts to model predictive control to smoothly bring unsatisfactory voltages inside the desired range of values. Using a sensitivity model, the controller calculates optimal power output changes of distributed generators to correct the network voltages, giving priority to reactive over active power. Simulations results are presented on a 32-bus test system and three variants of the optimization problem are compared. [less ▲]

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See detailComparison of the Heart-type fatty acid-binding protein (H-FABP) with the high sensitive cardiac troponin T in healthy runners
LE GOFF, Caroline ULg; MELON, Pierre ULg; BREVERS, Eric ULg et al

in Book of abstracts of 18th Annual Congress of the ECSS (2013, June)

Background: Heart-type fatty acid-binding protein (H-FABP) is a low molecular weight protein involved in the intracellular uptake and buffering of long chain fatty in the myocardium. It is an early marker ... [more ▼]

Background: Heart-type fatty acid-binding protein (H-FABP) is a low molecular weight protein involved in the intracellular uptake and buffering of long chain fatty in the myocardium. It is an early marker for acute coronary syndrome. Troponin T (TnT) is a component of the contractile apparatus of the striated musculature. Cardiac TnT is a cardio-specific, highly sensitive marker for myocardial damage. The aim of our study was to compare the results obtained with the H-FABP and the highly sensitive cardiac troponins (hsTnT) and to test their cardiospecificity in healthy runners. Methods: Twenty three runners (marathon) were enrolled. We drowned samples at three times: just before (T0), just after (T1), and three hours after the end of the race (T3). H-FABP was determined with a Randox immunoturbidimetric assay and hs-TnT with a Roche electrochemiluminescence immunoassay, both on Cobas 6000. A linear regression was calculated to observe if there is any correlation between the two biomarkers. Values above the 95th percentile for H-FABP (2.5ng/mL) and the 99th percentile for hsTnT (14ng/L) were considered as positive. Results: At T0, none of the subjects were positive for hsTnT but 35% were positive for H-FABP; at T1, 83% for hsTnT and 100% for H-FABP; at T3, 83% for hsTnT and 96% for H-FABP. At T0, the regression equation was H-FABP T0 = 3.9454 – 0.1001 x hsTnT T0; at T1: H-FABP T1 = 51.838 – 1.7026 x hsTnT T1; at T3: H-FABP T3 = 47.977 – 1.6193 x hsTnT T3. No correlation was observed between the two biomarkers at the different time. Conclusions: We observed a significant increase of H-FABP and hsTnT in runners. These markers are independent to each other. These values could biologically correspond to a heart ischemia. However, we suggested that exercise-induced cardiac hsTnT and H-FABP release is not a marker of exercise-induced pathology but likely a physiologic response to effort or an exercise-induced cardiac remodelling. [less ▲]

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See detailUsing mobile milking robots for special quality dairy products based on site specific grazing
Oudshoorn, F.W.; Philipsen, B.; Dufrasne, Isabelle ULg et al

in A Helgadóttir (Ed.) Grassland Science in Europe : The role of Grasslands in a Green Future - Threats and Perspectives in Less Favoured Areas (2013, June)

An option for combining grazing and automatic milking is Infield Automatic Milking, with more or less mobile infield automatic milking systems (IAMS), which have been practiced since 2008 in several ... [more ▼]

An option for combining grazing and automatic milking is Infield Automatic Milking, with more or less mobile infield automatic milking systems (IAMS), which have been practiced since 2008 in several European countries. This emerging technology can be used to harvest milk from specific areas, giving specialized dairies the possibility to market concept milk, cheese or butter. Terroir dairy can be a new way to increase marginal product value and thereby farm income. Three different options are described; i) the IAMS placed on a stationary platform in the field, ii) movable together with facilities necessary for the functionality from field to field, iii) as a self propelled moving unit that changes positions in the field every day, requiring transportation of the milk to the field border. All systems could guarantee dairy products based on maximum grazing for the period the pasture can provide sufficient feeding. Batch size depends on the dairies minimum process volume for the specific products, local conditions will be decisive for the amount of days needed for pooling before production. [less ▲]

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See detailL'emplâtre Isis et autres recettes d'origine égyptienne
Marganne, Marie-Hélène ULg

in Pardon-Labonnelie, Muriel (Ed.) La coupe d'Hygie. Médecine et chimie dans l'Antiquité (2013, June)

Study the context of emergence and spread of Isis plaster and other related recipes, which seem to come from an Egyptian priestly context.

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See detailNumerical investigation of continuous fiber glass drawing
Chouffart, Quentin ULg; Simon, Philippe; Terrapon, Vincent ULg

in Idelsohn, Sergio R; Papadrakakis, Manolis; Schrefler, Bernhard A (Eds.) Proceedings of the V International Conference on Computational Methods for Coupled Problems in Science and Engineering (2013, June)

The physics of glass fiber drawing is studied through numerical simulations and experimental measurements, with a focus on the fluid region, from the hole tip at the bushing plate to the glass transition ... [more ▼]

The physics of glass fiber drawing is studied through numerical simulations and experimental measurements, with a focus on the fluid region, from the hole tip at the bushing plate to the glass transition point. The influence of the different heat transfer mechanisms is investigated to understand their respective impact on fiberization, such as fiber radius attenuation and internal stresses. Numerical predictions are then compared to experimental data measurements obtained from a dedicated fiberization unit. Numerical and experimental results show a good agreement. In particular, it is found that the ambient air temperature and the radiation have an important impact on the fiber cooling rate. Moreover, for a prescribed fiber diameter, internal stresses are lower when operating at a higher temperature. [less ▲]

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See detailDistributed load interruption and shedding against voltage delayed recovery or instability
Otomega, Bogdan; Van Cutsem, Thierry ULg

in Proc. IEEE PES 2013 PowerTech Conference (2013, June)

This paper deals with a two-part system integrity protection scheme to be installed in distribution networks, to counteract fault-induced delayed voltage recovery or even short-term voltage instability ... [more ▼]

This paper deals with a two-part system integrity protection scheme to be installed in distribution networks, to counteract fault-induced delayed voltage recovery or even short-term voltage instability due to induction motors. The first part consists of a fast triggered but temporary reduction of some loads to facilitate motor re-acceleration after fault clearing. The second part resorts to load shedding, as a back-up. The scheme relies on purely distributed controllers; each of them measures a bus voltage and interrupts/disconnects load at the same bus. Tests have been performed on a generic MV/LV system. They illustrate the benefit of load interruption and the selectivity of the proposed scheme. [less ▲]

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See detailA Site-Specific Grain Yield Response Surface : Computing the Identity Card of a Crop Under Different Nitrogen Management Scenarios
Dumont, Benjamin ULg; Basso, Bruno; Leemans, Vincent ULg et al

in The acts of the EFITA2013 congress (2013, June)

At the parcel scale, crop models such as STICS are powerful tools to study the effects of variable inputs such as management practices (e.g. nitrogen (N) fertilization). In combination with a weather ... [more ▼]

At the parcel scale, crop models such as STICS are powerful tools to study the effects of variable inputs such as management practices (e.g. nitrogen (N) fertilization). In combination with a weather generator, we propose a general methodology that allows studying the yield variability linked to climate uncertainty, in order to assess the best practices in applying fertilizers. Our study highlights that, using the usual practice of Belgian farmers, namely applying three doses of 60kgN/ha, the yield’s distribution presents the highest degree of asymmetry. This implies the highest probability to achieve yields superior to the mean. The computed return time of expected yield shows that 9 years out of 10, a grain yield of 7.26 tons.ha-1 could at least be achieved. [less ▲]

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See detailPlatelet-rich plasma (PRP) to treat upper patellar tendinopathies
Kaux, Jean-François ULg; Croisier, Jean-Louis ULg; SIMONI, Paolo ULg et al

in Book of abstracts of 18th Annual Congress of the ECSS (2013, June)

Introduction: Tendinopathies, especially upper patellar tendinopathy also known as jumper’s knee, often remain rebel to conservative treatments. Several experimental studies have shown the healing ... [more ▼]

Introduction: Tendinopathies, especially upper patellar tendinopathy also known as jumper’s knee, often remain rebel to conservative treatments. Several experimental studies have shown the healing properties of platelet and their growth factors. These factors have the potentiality to improve healing of different tissues: bones, muscles, tendons... Researches have specifically demonstrated the platelets action as mediator and/or enhancer of tissue healing. On the other hand, such treatment has been totally removed of list of doping treatments. The aim of our study was to investigate the effect of 1 injection of PRP in patients suffering from chronic jumper’s knee. Methods: Patients performed imaging (US and MRI) and functional assessments, and a clinical examination using an algometer, before treatment and 6 weeks after PRP treatment. They were also invited to answer to questionnaire relative to pain and functional status. PRP was obtained from autologous blood using an apheresis system (COM.TEC, Fresenius). The injection of 6mL of PRP was realised without local anaesthesia into the proximal insertion of the patellar tendon. A 48h rest-time was recommended after infiltration. Afterwards, a submaximal eccentric reeducation was initiated 1 week after infiltration 3 times a week during 5 weeks. In case of pain, anti-inflammatory drugs were prohibited and patient were encouraged to take class I or II painbrakers. Our protocol was approved by Ethic Committee of University and University Hospital of Liège. Results: Eighteen patients with jumper’s knee were included in our study. Pre-injection tests revealed pain of the upper part of the patellar tendon just below the patella, associated with loss of function. Imaging exams confirmed diagnosis. Six weeks post-injection, the clinical status was improved for the majority of the patients, with a significant decrease of algo-functional scores. The pain reported during functional assessments was decreased (in particular for the eccentric actions), yet no significant improvement of physical performances was observed. We found no significant differences between imaging exams before and 6 weeks after PRP injection. Conclusion: One in situ injection of PRP clinically improved patients with jumper’s knee 6 weeks after treatment. Most patients reported a decrease of pain during day-life and through physical activities. However nor functional performances neither imaging were improved. A followup at 3 months is actually in process to evaluate more long term efficacy of PRP treatment. [less ▲]

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See detailTowards a concept of operation using BIM technologies to improve productivity in construction projects.
Tahrani, Souha; Schmitz, Dimitri ULg; Leonard, Michael et al

in Proceedings CSCE 2013 (2013, June)

The main objective of this paper is to evaluate the potential role of approaches that integrates the BIM and productivity measurement tools to increase the productivity in construction. A concept of ... [more ▼]

The main objective of this paper is to evaluate the potential role of approaches that integrates the BIM and productivity measurement tools to increase the productivity in construction. A concept of operation will be proposed in the context of a pilot project that is designed to be used in future projects that use a new constructive system which is developed by industrial partners; this system offers a controlled and protected building environment. The research methodology is structured into four steps. 1) Benchmarking the firm's current situation through direct observations, surveys and interviews to identify issues and challenges related to the use of technologies, the current process, and the organizational structure of the project. 2) Defining the desired situation based on the project’s stakeholders’ expectations. 3) Using Focus Groups to determine and sort the requirements for an instrumentation of the new Construction Process. 4) Determining the instrumentation to be installed to support the new operation modes that are to be used by industrial partners. This instrumentation is supported by BIM, Productivity and ICT tools, and will be validated through site tests and interviews with project’s stakeholders. Preliminary results showed a problem of coordination and communication in the project, and identified resistance factors to technology adoption, specifically BIM implementation. The paper also highlights several wastes that have been found during pilot project analysis, and that have been correlated to the wastes found from literature. [less ▲]

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See detailMineralogical characterization of a gold ore through a computational mineral liberation analysis
Rojas, Ronald; Torem, Mauricio; Merma, Antonio et al

in Proceedings of the XV Balkan Mineral Processing Congress - BMPC 2013 (2013, June)

This work presents the mineralogical characterization of a very low-grade Brazilian gold ore. The aim is to provide mineralogical information and liberation distribution characteristics in order to assess ... [more ▼]

This work presents the mineralogical characterization of a very low-grade Brazilian gold ore. The aim is to provide mineralogical information and liberation distribution characteristics in order to assess a possible economic byproducts recovery. This may include a direct tailings processing or alternative gold processing routes. It was studied the distribution of all minerals present in the ore, mainly the gangue minerals. Distribution based on speciation, particle size, mineralogical association and liberation determined through the use of the automated analytical Scanning Electron Microscope technique (MLA). The study is complemented with chemical and mineralogical analysis by XRF and XRD respectively. It also includes particle size analysis, gravity separation and magnetic separation tests. Chemical analysis showed that the ore consists essentially of SiO2 (62.33%), Al2O3 (15.95%), Fe2O3 (7.66%), K2O (4.60%), TiO2 (1%) and others (8.46%). Based on this analysis, the study was mainly directed to the characterization of titanium-bearing minerals due to its economic importance. Therefore, minerals as ilmenite, rutile and anatase were identified as the Ti-bearing minerals. After a meticulous analysis of the results, it was identified a possible route for processing TiO2, taking into account the mineralogical and liberation point of view. [less ▲]

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See detailModeling and simulation of the domestic energy use in Belgium following a bottom-up approach
Georges, Emeline ULg; Gendebien, Samuel ULg; Bertagnolio, Stéphane ULg et al

in Proceedings of the CLIMA 2013 11th REHVA World Congress & 8th International Conference on IAQVEC (2013, June)

The present paper presents a “bottom-up” approach dedicated to the modeling and simulation of the domestic energy use. This methodology focuses first on a microanalysis (i.e. modeling and simulation of a ... [more ▼]

The present paper presents a “bottom-up” approach dedicated to the modeling and simulation of the domestic energy use. This methodology focuses first on a microanalysis (i.e. modeling and simulation of a set of representative households). Results from this micro-analysis are then used and extended to allow drawing conclusions at a macro-scale. The methodology can be validated by comparing simulation results to annual national energy consumption indexes or synthetic load profiles (energy consumption profiles generated from values of predefined past periods). Once the method is validated, it can be used to study the impact of different retrofit scenarios on the annual energy use and on the energy demand profiles. This paper describes the methodology developed for Belgium. [less ▲]

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See detailIdentifying and modeling the integrated design process of net Zero Energy buildings
Attia, Shady ULg; Walter, Emmanuel; Andersen, Marilyne

in Proceedings of the High Performance Buildings - Design and Evaluation Methodologies Conference (2013, June)

High Performance Buildings (HPB), including Net Zero Energy Buildings (NZEBs) and nearly Zero Energy Buildings (nZEB) are emerging as an important market in Europe and around the world. However, there are ... [more ▼]

High Performance Buildings (HPB), including Net Zero Energy Buildings (NZEBs) and nearly Zero Energy Buildings (nZEB) are emerging as an important market in Europe and around the world. However, there are very few studies that aim to model the process of HPBs and define key design processes, decisions and competencies of design teams. More importantly, there is hardly any documentation processes on tools currently being used to design high performance building. Therefore, the purpose of this paper is to identify, model and propose a generic integrated process maps for HPB. The generic process map focuses on the design phases steps, roles and tools used. The research methodology is based on literature review and a case study. With the help of a process modelling software (TIBCO), a Swiss office building (Green Office) is used to validate the produced process maps. The visual maps delivers insights on the integrated design process reporting on the means of improving the delivery of HPBs. [less ▲]

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See detailASSESSMENT OF FATIGUE RELIABILITY FOR JACKET-TYPE OFFSHORE PLATFORMS CONSIDERING DYNAMIC BEHAVOIR
Reza Khedmati, Mohammad; Rigo, Philippe ULg; Amrane, Amirouche ULg et al

in Proceedings of the ASME 2013 32nd International Conference on Ocean, Offshore and Arctic Engineering OMAE 2013 (2013, June)

In order to traditionally investigate the strength of marine structures, the structure is subjected to a maximum static load. However, the marine structures are usually suffering environmental forces ... [more ▼]

In order to traditionally investigate the strength of marine structures, the structure is subjected to a maximum static load. However, the marine structures are usually suffering environmental forces varying with time. Wave forces are the most important time dependent loading that causes fatigue in structural elements and joints. In this paper different methods base on S-N curve and linear elastic failure mechanics are presented. The governing equations and theories that are used in each method are expressed and the application of each method will be discussed. The two main methods of deterministic analyses are: stressbased approach (S-N curve approach) and linear elastic fracture mechanics (LEFM) approaches. These approaches are applicable to different analyzing strategies, ie the first approach is used for cases in which general form of fatigue is dominant, but the latter involves the calculations of reliability as functions of crack geometry and its boundary conditions. The SPD12C jacket platform is also modeled as a case study and the results of fatigue reliability analysis are presented. In this paper a comprehensive method is presented to accurately predict the reliability of offshore platforms. This method is based on S-N curve and the results are compared with the fatigue life of joints. Due to nonlinear interaction of soil and piles and the other affecting parameters such as flexibility of joints, non Gaussian procedure of loading, and nonlinearity of reaction force, the precise analyzing of stress levels will be impossible and a complex numerical analysis could only give limited information about the statistical properties of stress. In order to perform the fatigue analysis and predicting the cycles of stress SACS was used which is known as a powerful software in designing and analyzing offshore structures. In this paper the whole structure was modeled subjected to different forces such as wave and sea currents. The effects of parameters such as marine growth and interaction of soil and piles are also included. The latter is shown to have a significant effect on determination of fatigue life of the platform. [less ▲]

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See detailNumerical Simulation of Double Cup Extrusion Test using the Arbitrary Lagrangian Eulerian Formalism
Boman, Romain ULg; Koeune, Roxane; Ponthot, Jean-Philippe ULg

in Proceedings of Coupled Problems 2013 (2013, June)

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See detailComparison of a fluid and a solid approach for the numerical simulation of Friction Stir Welding with a non-cylindrical pin
Bussetta, Philippe ULg; Dialami, Narges; Boman, Romain ULg et al

in Proceedings of "V International Conference on Computational Methods for Coupled Problems in Science and Engineering" (2013, June)

Friction Stir Welding (FSW) process is a solid-state joining process during which materials to be joined are not melted. As a consequence, the heat-affected zone is smaller and the quality of the weld is ... [more ▼]

Friction Stir Welding (FSW) process is a solid-state joining process during which materials to be joined are not melted. As a consequence, the heat-affected zone is smaller and the quality of the weld is better with respect to more classical welding processes. Because of extremely high strains in the neighbourhood of the tool, classical numerical simulation techniques have to be extended in order to track the correct material deformations. The Arbitrary Lagrangian Eulerian (ALE) formulation is used to preserve a good mesh quality throughout the computation. With this formulation the mesh displacement is independent from the material displacement. Moreover, some advanced numerical techniques such as remeshing or a special computation of transition interface is needed to take into account non-cylindrical tools. During the FSW process, the behaviour of the material in the neighbourhood of the tool is at the interface between solid mechanics and fluid mechanics. Consequently, a numerical model of the FSW process based on a solid formulation is compared to another one based on a fluid formulation. It is shown that these two formulations essentially deliver the same results in terms of pressures and temperatures. [less ▲]

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See detailExuberant inflammatory reaction after an infiltration of platelet-rich plasma to treat tendinopathy
Kaux, Jean-François ULg; Croisier, Jean-Louis ULg; LEONARD, Philippe ULg et al

in Book of abstracts of 18th Annual Congress of the ECSS (2013, June)

Background: PRP, obtained from centrifuged autologous blood, contains a large quantity of growth factors, which may enhance the tissue healing processes. Local infiltration of PRP represents a relatively ... [more ▼]

Background: PRP, obtained from centrifuged autologous blood, contains a large quantity of growth factors, which may enhance the tissue healing processes. Local infiltration of PRP represents a relatively new treatment for tendinopathies. To date, no side effects have been reported after infiltration of PRP to treat tendinopathy. Case report: A 35-year-old patient had a right upper patellar tendinopathy which was resistant to all conservative treatments for more than 6 months. The patient was a type 1 diabetic (well controlled). He had an intratendinous infiltration of 6 mL of PRP (8.105 platelets/mm3, almost no red or white blood cells) after disinfection but without local anaesthetic. Immediately following the infiltration, local cryotherapy was performed for 15 minutes. NSAIDs were avoided, but class-1 or -2 pain-killers were authorised if necessary. A standardised sub-maximal eccentric rehabilitation should have been started 1 week after. However, the patient experienced local swelling with erythema, increased heating and pain which appeared just underneath the patella, but without biological inflammatory syndrome. A great Doppler signal in a thicker patellar tendon was observed by US, but there was no sign of local infectious disease demonstrated by either CT or MRI. However, the local inflammation did not decrease after a progressive 3-week treatment of local cryotherapy, local and oral NSAIDs and colchicine 1 mg. Thus, an insidious infection was suspected, even though there was neither evidence of biological inflammatory syndrome nor sign of infectious lesion on imagery examination. An antibiotic therapy (rifampicine 600 mg + minocycline 100 mg) was initiated for 3 months. Finally, a 3-phase bone scintigraphy suggested the presence of a complex regional pain syndrome type 1 treated by a classical physical therapy and concomitant class-2 pain killers. The evolution was favourable after 6 months of symptomatic treatment, and the pain decreased to a level similar to that before the infiltration of PRP. Discussion/Conclusions: This case report draws attention to potential side effects that are linked to this new therapy by infiltration of platelet rich plasma in case of tendinopathy, in particular when used in patients with type 1 diabetes. Thus, the balance between benefits and risks must be carefully evaluated before using this treatment in patients with type 1 diabetes. Reference: Platelet-rich plasma application in the management of chronic tendinopathies. Acta Orthop Belg 2013; 79: 10-15. [less ▲]

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See detailShaking table tests on unreinforced load-bearing masonry walls - Comparison with simple rocking models
Mordant, Christophe ULg; Dietz, Matt; Degée, Hervé ULg

in ECCOMAS Thematic Conference - COMPDYN 2013: 4th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering, Proceedings - An IACM Special Interest Conference (2013, June)

Assessment of the overall seismic performances of multi-storey unreinforced masonry structures requires an appropriate characterization of the behaviour of their structural components, in particular when ... [more ▼]

Assessment of the overall seismic performances of multi-storey unreinforced masonry structures requires an appropriate characterization of the behaviour of their structural components, in particular when these are subjected to a dynamic ground motion input. In order to develop a better understanding on this issue and in a further perspective of investigating the consequences of the presence of 1 cm thick rubber elements used for improving the sound-proofing performances of the building, shaking table tests have been carried out in the framework of the European project SERIES. Four single walls were tested. These were built with high resistance thin-bed layered clay masonry with empty vertical joints. Two of them had an aspect ratio close to 1, while the other two were close to 0.4. One wall of each aspect ratio included rubber devices at its bottom and top to enable comparisons and conclusions about the influence of rubber on the wall behaviour. The test results were then partially compared to results obtained with a theoretical rocking model considering the wall as a rigid body. The results summarized in the present contribution evidence a significant rocking behaviour for the highest input acceleration levels. Characterization of this behaviour is however strongly dependent on the aspect ratio of the wall and on the presence or not of rubber devices in terms of natural frequencies, damping, dynamic amplifications and progressive damage with increasing acceleration levels. It is also showed that the theoretical rocking predictions are in good agreement with the experimental results for high acceleration levels, while the behaviour is closer to the one of a cantilever for the lower levels. It is finally evidenced that, in presence of acoustic rubber devices, amplitudes of the rocking motion are increased but with a more limited damaging of the wall because of the capacity of the rubber to absorb the impact energy. Results of this study on single walls are expected to be further extended to global masonry structures, account taken for the influence of actual boundary conditions of the wall. [less ▲]

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See detailUnderstanding the role of subcultures in the enterprise architecture process
Niemietz, Hella; De Kinderen, Sybren; Constantinidis, Christina ULg

in ECIS 2013 Proceedings (2013, June)

Enterprise Architecture (EA) is positioned as an instrument for coordinating enterprise transformation. However, existing EA approaches pay less attention to soft factors that may have an impact on ... [more ▼]

Enterprise Architecture (EA) is positioned as an instrument for coordinating enterprise transformation. However, existing EA approaches pay less attention to soft factors that may have an impact on enterprise transformations. The existence of different organisational subcultures is not taken into account although it is considered as significant in the context of change. The social alignment of business and IT groups plays, for instance, a major role in transformations and in EA. This paper presents the first step of a larger study addressing the question how differences between organisational subcultures contribute to struggles/failure of EA-guided transformations. We use a series of qualitative, unstructured expert interviews to explore to what extent and how cultural differences can trigger struggles in EA-guided transformations from an architect’s perspective. Based on these interviews, an initial conceptual model is developed. This model suggests that communication breakdowns act as an intermediary factor between differences in organisational subculture and transformation struggles. A second round of expert interviews is used for the assessment and elaboration of the initial model focusing on communication breakdowns. The analysis of these interviews supports the intermediary role of communication breakdowns and refines the concepts of the model. [less ▲]

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See detailA new computational method for nonlinear normal modes of nonconservative systems
Renson, Ludovic ULg; Kerschen, Gaëtan ULg

in Proceedings of the Euromech Colloquium n. 541 - New Advances in the Nonlinear Dynamics and Control of Composites for Smart Engineering Design (2013, June)

The concept of nonlinear normal modes (NNMs) was introduced with the aim of providing a rigorous generalization of normal modes to nonlinear systems. Initially, NNMs were defined as periodic solutions of ... [more ▼]

The concept of nonlinear normal modes (NNMs) was introduced with the aim of providing a rigorous generalization of normal modes to nonlinear systems. Initially, NNMs were defined as periodic solutions of the underlying conservative system, and continuation algorithms were recently exploited to compute them. To extend the concept of NNMs to nonconservative systems, Shaw and Pierre defined an NNM as a two-dimensional invariant manifold in the system’s phase space. This contribution presents a novel algorithm for solving the set of partial differential equations governing the manifold geometry numerically. The resolution strategy takes advantage of the hyperbolic nature of the equations to progressively solve them in annular regions. Each region is defined by two different iso-energy curves and equations are discretized using a specific finite element technique. The proposed strategy also offers the opportunity to estimate the frequency-energy dependence of the mode without using time integration. The algorithm is applied to both conservative and nonconservative systems. [less ▲]

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See detailThe contributions of pairs of parallel surfaces in a simple analytical model of room reverberation
Embrechts, Jean-Jacques ULg

in I.C.A. (Ed.) Proceedings of the 2013 ICA Congress (2013, June)

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See detailExploiting Localization for Faster Power System Dynamic Simulations
Aristidou, Petros ULg; Fabozzi, Davide; Van Cutsem, Thierry ULg

in Proc. IEEE PES 2013 PowerTech Conference (2013, June)

This paper proposes an algorithm for exploiting the localized response of power system components to accelerate dynamic simulations. During the simulation, components marginally participating to the ... [more ▼]

This paper proposes an algorithm for exploiting the localized response of power system components to accelerate dynamic simulations. During the simulation, components marginally participating to the system dynamics are characterized as latent and their dynamic models are replaced by much simpler equivalents. At the same time, components with significant dynamic activity are characterized as active and their original dynamic models are used. Based on the criterion proposed, components switch status between active and latent to increase performance while retaining accuracy. Two realistic test systems, a medium-scale and a large-scale, are used for the performance evaluation of the proposed method. [less ▲]

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See detailIsocinétisme : aspects spécifiques chez le sportif
Croisier, Jean-Louis ULg; Delvaux, François ULg; Kaux, Jean-François ULg et al

in Abstract Book de la 1ère Journée de Rééducation de l'INSEP (2013, June)

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See detailControl of Dispersed Generation to Regulate Distribution and Support Transmission Voltages
Valverde, Gustavo ULg; Van Cutsem, Thierry ULg

in Proc. IEEE PES 2013 PowerTech Conference (2013, June)

This paper presents an on-line centralized controller based on Model Predictive Control concepts to regulate distribution network voltages, and possibly support transmission network. It computes and ... [more ▼]

This paper presents an on-line centralized controller based on Model Predictive Control concepts to regulate distribution network voltages, and possibly support transmission network. It computes and applies a sequence of changes of the distributed generators power outputs to progressively meet a set of operation constraints at distribution, and possibly transmission level. An 11-kV, 75-bus test system with 22 distributed generators is used to illustrate the performance of the proposed controller when transmission system support is requested. Comparisons with single-step open-loop control are also provided. [less ▲]

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See detailDynamic Simulations of Combined Transmission and Distribution Systems using Decomposition and Localization
Aristidou, Petros ULg; Van Cutsem, Thierry ULg

in Proc. IEEE PES 2013 PowerTech Conference (2013, June)

Simulating a power system with both transmission and distribution networks modeled is a challenging task. On the one hand, it is difficult to set up equivalents restituting the dynamic behavior of ... [more ▼]

Simulating a power system with both transmission and distribution networks modeled is a challenging task. On the one hand, it is difficult to set up equivalents restituting the dynamic behavior of aggregated loads and distributed generation units. On the other hand, representing all distribution networks in detail is computationally very demanding. In this paper, the combination of a domain-decomposition approach with the exploitation of the localized nature of power system responses to disturbances is proposed. Distribution networks marginally participating to the system dynamics are automatically replaced by simple models, while the others are simulated with full detail, thereby preserving simulation accuracy. [less ▲]

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See detailApport des TICE dans la mise en place d'une pédagogie active pour les grands groupes
Colaux, Catherine ULg; Georges, François ULg; Poumay, Marianne ULg

in Actes du VIIè colloque Questions de Pédagogie dans l’Enseignement Supérieur (2013, June)

Il n'est pas toujours simple pour un étudiant de comprendre le bien fondé de certains cours généraux. Pour éviter leur démotivation il est important de pouvoir les aider à donner du sens à ceux-ci, mais ... [more ▼]

Il n'est pas toujours simple pour un étudiant de comprendre le bien fondé de certains cours généraux. Pour éviter leur démotivation il est important de pouvoir les aider à donner du sens à ceux-ci, mais comment procéder dans de grands auditoires où les cours ex cathedra font légion ? Utilisées en guise de préparation de cours magistraux, les TICE exploitées dans certaines conditions (collaboration, contrôle laissé aux apprenants, réflexivité et temps) donneraient plus d'authenticité aux exposés et offriraient aux apprenants d'y être davantage actifs [less ▲]

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See detailBilan de 5 années de conception et de régulation d'outils pédagogiques innovants: implémentation d'un portfolio dans un enseignement de l'architecture par compétences
Scheffers, Patricia ULg

in Actes du VIIème Colloque: Questions de Pédagogies en Enseignement Supérieur (2013, June)

Entre 2007 et 2012, des innovations pédagogiques initialement conçues de façon intuitive et ponctuelle par quelques enseignants se sont développées, améliorées et généralisées. Comment ont-elles ... [more ▼]

Entre 2007 et 2012, des innovations pédagogiques initialement conçues de façon intuitive et ponctuelle par quelques enseignants se sont développées, améliorées et généralisées. Comment ont-elles progressivement pris corps d'un point de vue théorique ? Comment sont-elles devenues les composantes essentielles d'un portfolio qui se développera peut-être bientôt sur plusieurs années du cursus ? Comment l'ensemble s'articule-t-il autour d'un projet de référentiel de compétences facultaire ? [less ▲]

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See detailInvestigation of biological markers to evaluate the adaptation of the newborn Belgian Blue calf to the extrauterine life. A pilot study.
Ronzoni, Anna ULg; Theron, Léonard ULg; De Marchin, Emmanuelle et al

in Dalin, Göran (Ed.) 15th International Conference on Production Diseases in Farms Animals, Book of Abstracts (2013, June)

Adaptation to extrauterine life and immunity transfer at calving are more at stake when dealing with highly productive breeds such as the Belgian Blue Cattle Breed (BBCB). The purpose of the present pilot ... [more ▼]

Adaptation to extrauterine life and immunity transfer at calving are more at stake when dealing with highly productive breeds such as the Belgian Blue Cattle Breed (BBCB). The purpose of the present pilot study was to evaluate different blood markers, from the birth to the first week of life in BBCB calves, in order to investigate fundamental aspects of the adaptation to the extrauterine life as passive immunity transfer and early energy metabolism. Eighty calves coming from 10 different farms located in Wallonia (Belgium) were enrolled. A clinical examination was performed to verify viability and maturity at birth. Blood samples were collected at birth, day 1 and day 3 to 7. Passive immunity transfer analysis included serum and colostrum immunoglobulin G (IgG) concentration, and plasmatic selenium concentration (Se). Glycemia, serum insulin and cortisol concentration have been considered for the energy metabolism analysis. The data collected were statistically analysed using logistic regression and unpaired t-test. All calves were born alive, viable and mature by caesarean section. Mortality rate was 0% at one week and 5% at three months. Only 33% of calves had an IgG concentration >16g/L after one week of age, while only 34% of colostra had an IgG concentration >70g/L. Glycemia and serum insulin concentration at birth were significantly lower than other breeds, and plasmatic selenium concentration were coherent with low supplemented dams. We compared calves across IgG concentration classes (>16 g/L vs <16g/L). The crosssectional analysis of the risk of FPT when given low IgG concentration colostra has shown a non significant odd ratio (OR 1,058 and 0,39116 g/L) (p<0,001). No significant difference has been shown between cortisol and glycemia (p=0,3) nor insulin and glycemia (p=0,2) at birth. These data suggest a significant difference in BBCB calves on several metabolic markers, but they also revealed that immunity transfer and micronutrition of pregnant hyper-productive dams remain a challenge in modern farms. [less ▲]

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See detailPrediction and measurement of the random incidence scattering coefficient of periodic reflective rectangular diffuser profiles
Schmich-Yamane, Isabelle; Embrechts, Jean-Jacques ULg; Müller-Trapet, Markus et al

in Proceedings of the 2013 ICA Congress (2013, June)

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See detailImpact of different endurance races on the heart: the point of view of the biologist
LE GOFF, Caroline ULg; MELON, Pierre ULg; Thébault, Jérémie et al

in Book of abstracts of 18th Annual Congress of the ECSS (2013, June)

Objective The aim of this study was to investigate the impact of intense exercise, represented by different endurance races, in relationship with oxidative stress and cardiac markers. In a second time, we ... [more ▼]

Objective The aim of this study was to investigate the impact of intense exercise, represented by different endurance races, in relationship with oxidative stress and cardiac markers. In a second time, we tried to demonstrate if oxidative stress induced by physical activity is a physiological or pathological process, and to establish some issues to diagnose the risk of sudden death in athletes. Methods Four populations were compared, a control group of 16 participants “sedentary” (37 ± 4,39 years old), a group of 24 semi-marathon runners (41 years ± 8,76 years old), a group of 28 marathon runners (44,1 ± 8,37 years old) and a group of 33 ultra-trail runners (45,8 ± 8,7 years old). Three blood tests were drowned, one just before, one just after, and the last three hours after the end of the race.Different oxidative and stress and cardiac biomarkers were measured. The ultra-trail runners will be subject to an echocardiography and an ECG pre- and post-race. For statistical analysis, STATISTICA 10 software was used. We performed a non-parametric test of Kruskal-Wallis for independent sample and a Friedman ANOVA for paired samples. Results Myeloperoxydase increased during exercise, but the release is less important according to the level of training of the runners. GSH/GSSG ratio seems to remain stable during the race but it could increase during the 24 hours post-race. There is a decrease in lipidic peroxidation during exercise. But, we note an increase of creatine kinase, isoform MB, myoglobin and C-reactive protein during the race. We observe an increase of troponin T and natriuretic peptide but with a different kinetic than the kinetic obtained for a myocardial infarction. Medical imaging in ultra-trail runners present cardiac adaptations to endurance training, as left ventricular hypertrophy (LVH) and incomplete right bundle branch block (IRBBB). A decrease of systolic and diastolic volumes of the left ventricle and a decrease of longitudinal strain were observed by echocardiography at the end of the race. Conclusion Endurance races induce the income of oxidative stress objectified by different biomarkers increase, but a cell necrosis is not specially observed. In fact, the increase of the cardiac markers during endurance races but may be explained by a transient modification of myocyte permeability, with a release of pool cytosolic. These races may induce micro-muscle damages causing the appearance of an inflammatory process explaining our observations of markers of inflammation. For the medical imaging, it was observed a myocardial adaptation to training and a transient impairment of ventricular function due to dehydration. [less ▲]

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See detailSmart agritourism: How to take advantage of local and regional assets?
Dubois, Charline ULg; Schmitz, Serge ULg

in Helgadóttir, Guðrún (Ed.) NAF 2013 – Rural Tourism, Challenges in Changing Times (2013, June)

Agritourism, subset of rural tourism, is defined in Wallonia and in Grand Duchy of Luxembourg as a tourist accommodation or a set of tourist activities on an active farm. In these regions, rural ... [more ▼]

Agritourism, subset of rural tourism, is defined in Wallonia and in Grand Duchy of Luxembourg as a tourist accommodation or a set of tourist activities on an active farm. In these regions, rural environment becomes a recreation place for tourist seeking for rurality and also proximity of agriculture. Because of the difficulties of some agricultural areas in West European countryside, some farmers, actors of rural milieu in transformation, open their farmhouse to g! uests while other actors, among which authorities, imagine agr! itourism as an easy and magic solution to the safeguard of rural life. This paper analyses the agritourism development through its socio-economic and environmental assets to understand what influences its development in a particular region. How does it deal with environmental assets, relative proximity and local community? The analysis is based on data collected through surveys and interviews in Wallonia and in the Grand Duchy of Luxembourg: 1148 questionnaires were administered in tourist locations in July and August 2012, and 31 life histories were collected from farmers these last three winters. The paper highlights that the farm has both to find a niche on the rural tourist market and to take advantage of embeddedness in the local and the regional contexts. This approach of linking typology of Walloon and Luxembourg agritourist products, type of rural areas and geographical settings shows that it cannot be limited only to environmental assets and that other factors infl! uence the development of particular agritourist products such as the accessibility, the local community, the hospitality, the rural development policy, the farming orientation, and the complementarity with tourist places. [less ▲]

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See detailUse of Time- and Frequency-Domain Approaches for Damage Detection in Civil Engineering Structures
Nguyen, Viet Ha; Mahowald, Jean; Maas, Stefan et al

in Maia, NMM; Neves, NM; Sampaio, RPC (Eds.) International Conference on Structural Engineering Dynamics : ICEDyn 2013, Sesimbra 17-19 June 2013 (2013, June)

The aim of this paper is to apply both time- and frequency-domain-based approaches on real-life civil engineering structures and to assess their capability for damage detection. The first structure is the ... [more ▼]

The aim of this paper is to apply both time- and frequency-domain-based approaches on real-life civil engineering structures and to assess their capability for damage detection. The first structure is the Champangshiehl Bridge located in Luxembourg. Several damage levels were intentionally created by cutting a growing number of prestressed tendons and vibration data were acquired by the University of Luxembourg for each damaged state. The second example consists in reinforced and prestressed concrete panels. Successive damages were introduced in the panels by loading heavy weights and by cutting steel wires. The illustrations show different consequences in damage identification by the considered techniques. [less ▲]

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See detailDetection and Localisation of Damage on Industrially Produced Concrete Slabs Through Time- and Frequency-Domain Approaches
Nguyen, Viet Ha; Mahowald, Jean; Golinval, Jean-Claude ULg et al

in Carrera, E; Miglioretti, F; Petrolo, M (Eds.) 6th ECCOMAS Thematic Conference on Smart Structures and Materials (SMART2013) (2013, June)

The objective of this work is to address the problem of damage detection in civil engineering structures using non-destructive techniques and dynamic measurements. To this purpose, time- or frequency ... [more ▼]

The objective of this work is to address the problem of damage detection in civil engineering structures using non-destructive techniques and dynamic measurements. To this purpose, time- or frequency-domain methods are used for the diagnostics. It consists in practical output-only techniques as Stochastic Subspace Identification (SSI) for modal identification or Enhanced Principal Component Analysis (EPCA) for detecting the presence of damage. The use of the Hankel matrix instead of the observation matrix improves effectively the robustness of these methods. Damage localization is based on Frequency Response Functions (FRFs) and sensitivity analysis of PCA results. The efficiency of the above-mentioned methods has been demonstrated in earlier studies mainly on numerical models and small-scale laboratory experiments [3, 4]. It was also tested successfully on industrial examples to perform machine condition monitoring using a reduced set of sensors [2]. In this work, the investigation is performed on precast prestressed and non-prestressed concrete slabs. Successive damages were artificially introduced in the slabs by loading heavy weights and by cutting steel wires, which induced cracks in the structure. The examples show the consequences of the considered techniques for damage identification. The results that are very different between prestressed and non-prestressed slabs may be used as input for the condition control of this kind of structures. [less ▲]

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See detailThe influence of grinding media alloys on the flotation performances at Ellatsite plant (Bulgaria)
Bastin, David ULg; Gaydardzhiev, Stoyan ULg; Jacques, Simon et al

in Proceedings of the XV Balkan Mineral Processing Congress (2013, June)

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See detailNonlinear dynamic analysis of an F-16 aircraft using GVT data
Noël, Jean-Philippe ULg; Renson, Ludovic ULg; Kerschen, Gaëtan ULg et al

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

This paper aims at investigating the nonlinear dynamics of an F-16 aircraft, based upon sine-sweep data collected during a ground vibration test (GVT) campaign. Various analysis techniques, including the ... [more ▼]

This paper aims at investigating the nonlinear dynamics of an F-16 aircraft, based upon sine-sweep data collected during a ground vibration test (GVT) campaign. Various analysis techniques, including the mere visual inspection of the time series, the wavelet transform and the restoring force surface method, are utilised and reveal that the F-16 wing-to-payload mounting interfaces exhibit both softening and hardening nonlinearities. [less ▲]

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See detailLes macrophytes dans les ruisseaux de référence wallons: caractérisation des sites et typologie floristique
Sossey Alaoui, Khadija ULg; Galoux, Daniel; Rosillon, Francis ULg

in Colloque international des Macrophytyes: IRSTEA, Bordeaux 28-30 mai 2013 (2013, May 30)

La Directive européenne cadre 2000/60/CE sur l’eau a pour objectif l’atteinte du bon état écologique et du bon état chimique au sein des bassins hydrographiques, d'ici 2015. Pour établir l’état écologique ... [more ▼]

La Directive européenne cadre 2000/60/CE sur l’eau a pour objectif l’atteinte du bon état écologique et du bon état chimique au sein des bassins hydrographiques, d'ici 2015. Pour établir l’état écologique, la Directive impose de mesurer l’écart à la référence pour les indicateurs de la qualité biologique des cours d’eau (macroinvertébrés, diatomées, poissons, macrophytes et phytoplancton). L’élaboration d’une typologie macrophytique des ruisseaux de référence du bassin hydrographique de la Meuse, en Wallonie est l’objectif de l’étude. Les 50 sites étudiés font l’objet d’une caractérisation physico-chimique et mésologique et ensuite de relevés de végétation. Ceux-ci sont effectués sur des segments de cours d’eau de 100m de long et le recouvrement de chaque espèce est estimé selon une échelle d’abondance. Les ruisseaux étudiés peuvent être considérés comme le résultat d’un inventaire quasi exhaustif pour la Wallonie. Les plantes supérieures (hydrophytes), les mousses, les hépatiques, les macroalgues sont identifiées sur le terrain et au laboratoire à l’aide du binoculaire et du microscope. Le degré de la pente, l’altitude de la source et du site, l’occupation du sol, la géologie et certaines caractéristiques physico-chimiques de l’eau (ph, conductivité, teneur en calcium, magnésium et alcalinité) permettent de caractériser les stations. Six ensembles de ruisseaux avec leurs espèces caractéristiques sont mis en évidence par le "Two-Way Clustering" et "l’Indicator Species". L'analyse du déterminisme de distribution de la végétation dans les différents ensembles montre que ces derniers sont étroitement liés aux régions naturelles et leur typologie s’inscrit dans la typologie physique choisie par le Service public de Wallonie. [less ▲]

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See detailThe economic and environmental feasibility of biogas buses in Liege
Mostert, Martine ULg; Limbourg, Sabine ULg

in 2013 BIVEC-GIBET Transport Research Days - Proceedings (2013, May 30)

Everyday, many students at the University of Liège have to drive to the Sart-Tilman village to attend their courses. These journeys are responsible for the emission of harmful particles which have ... [more ▼]

Everyday, many students at the University of Liège have to drive to the Sart-Tilman village to attend their courses. These journeys are responsible for the emission of harmful particles which have negative impacts on climate and human health. This paper analyzes the economic and environmental feasibility of using biogas buses for public transport in Liège. The idea of implementing biogas buses is based on the proposed recycling of organic waste by the company INTRADEL, which manages and treats waste in the region. The economic and environmental advantages and drawbacks of biogas buses are developed and compared with those of the current diesel bus fleet. The main conclusion of this study is that, while internalizing external costs due to pollution, the use of biogas buses becomes an attractive option compared with classical diesel buses. Nevertheless, it requires investment and might lead to resistance to change. However, it remains a good solution for the reduction of CO2 emissions. [less ▲]

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See detailCORPORATE SUSTAINABILITY, STRATEGY AND ACCOUNTING CONTROLS: AN EXPLORATION OF CORPORATE PRACTICES
Crutzen, Nathalie ULg

in Actes du 34ème congrès annuel de l'AFC (2013, May 30)

The accounting and management control literature demonstrates the key role of management control to support strategy implementation. However, despite several calls in the social and environmental ... [more ▼]

The accounting and management control literature demonstrates the key role of management control to support strategy implementation. However, despite several calls in the social and environmental accounting research (Parker, 2000; Chung and Parker, 2008), to date, very few studies have explored how management controls support the implementation of a sustainability strategy in practice. With reference to Malmi and Brown framework (2008), this paper explores the existence of a selection of accounting-based controls (planning, cybernetic control as well as reward and compensation systems) to support sustainability strategy deployment. Concretely, based on the qualitative analysis of seven cases, it investigates what kind of accounting-based management controls exists in multinational corporations to support the implementation of an explicit sustainability strategy [less ▲]

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See detailComparison between analytical and optimal control techniques in the differential drag based rendez-vous
Dell'Elce, Lamberto ULg; Kerschen, Gaëtan ULg

in Proceedings of the 5th International Conference on Spacecraft Formation Flying Missions & Technologies (2013, May 29)

The focus of this study is on differential drag for propellantless satellite rendez-vous. This technique is particularly attractive for low-Earth-orbit small satellites for which stringent weight ... [more ▼]

The focus of this study is on differential drag for propellantless satellite rendez-vous. This technique is particularly attractive for low-Earth-orbit small satellites for which stringent weight constraints apply. Most existing contributions are based on bang-bang strategies, which may be difficult to implement in practice. This is why the present paper proposes a novel strategy integrating pseudospectral optimal control for maneuver planning and model predictive control for dealing with uncertainties and unmodeled dynamics. One important advantage of this methodology is that it can naturally account for attitude dynamics and constraints, which, in turn, paves the way for the practical realization of differential drag-based rendez-vous. A realistic scenario involving two nanosatellites of the QB50 constellation is considered to illustrate and validate the proposed developments. In addition, a comparison of this numerical technique with an existing analytic solution is carried out, and their respective pros and cons are discussed. [less ▲]

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See detailThe Solar Sail Material (SSM) Project : Results of Activities
Dalla Vedova, Florio; de Wilde, Don; Semprimoschnig, Christopher et al

in The Third International Symposium on Solar Sailing: Book of abstracts (2013, May 28)

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See detailPsychosocial needs and perception of inequity: How spouses react to the cancer of their partner?
Wagener, Aurélie ULg; Bragard, Isabelle ULg; Jonius, Bénédicte et al

in 2013 BAPS Annual Meeting : Conference booklet (2013, May 28)

Background. Several studies have highlighted the importance of psychosocial needs in cancer patients’ spouses. Our study’s aim was to reduce these spouses’ needs, using a combination of two ... [more ▼]

Background. Several studies have highlighted the importance of psychosocial needs in cancer patients’ spouses. Our study’s aim was to reduce these spouses’ needs, using a combination of two psychotherapeutic methods: 1. Psychosocial needs’ organization into a hierarchy; 2. Problem-solving method. We also assessed perception of inequity, which is a new concept used in psycho-oncology. This perception focusses on two feelings that spouses might experience in their relationships: firstly, the feeling of overbenefit and underinvestment; secondly, the feeling of underbenefit and overinvestment. Method. A longitudinal design with three assessments (T0,T1,T2) and two groups (experimental, control) was employed. Spouses fulfilled questionnaires: socio-demographic questionnaire, Psychosocial Needs Inventory, Perception of Inequity, Hospital Anxiety and Depression Scale. At T0, all participants organised their psychosocial needs into a hierarchy. Experimental group practiced problem-solving method before control group. Indeed, experimental group practiced it between T0 and T1 while control group practiced it only between T1 and T2. Results. Thirty-seven spouses participated: N experimental group=19; N control group=18. Whenever the combination was given, repeated measures’ ANOVAs highlighted a significant decrease in unsatisfied psychosocial needs when participants have received both methods. Nevertheless, our results did not replicate previous findings according to which spouses experience a higher feeling of overinvestment and underbenefit than feeling of underinvestment and overbenefit. Discussion. Our results underline the interest of proposing psychotherapeutic methods to cancer patients’ spouses to reduce unsatisfied psychosocial needs: clinical implications will be further discussed. Moreover, perception of inequity is a significant concept in psycho-oncology which consequences will also be discussed. [less ▲]

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See detailCombination of actor’s play training and assertiveness program to reduce difficulties in self-affirmation: A preliminary study.
Wagener, Aurélie ULg; Delvaux, Muriel ULg; Sarto, Danielle et al

in 2013 BAPS Annual Meeting : Conference booklet (2013, May 28)

BACKGROUND. Difficulties in assertiveness are often reported by individuals suffering from various psychological problems involving anxiety, depression. Cognitive and behavioral therapeutic procedures ... [more ▼]

BACKGROUND. Difficulties in assertiveness are often reported by individuals suffering from various psychological problems involving anxiety, depression. Cognitive and behavioral therapeutic procedures have already proven their effectiveness in helping these patients. The aim of our study was to test the efficacy of new therapeutic procedure, inspired by the third wave of behavioral and cognitive psychotherapies. METHOD. Our study used an actor’s play training combined with an assertiveness program which comprised ten sessions: five of which were animated by an actress and five by a psychologist-psychotherapist. Each actor play’s session was given alternatively with a psychoeducation’s session. Twenty subjects participated in this program. They fulfilled these pre and post-test assessments: social self-efficacy questionnaire, self-affirmation scales, self-esteem scale, communication scale, anxiety and depression scales. Repeated measures’ ANOVAs have been used to compare pre and post-test results. RESULTS. Results showed statistically significant improvements on each dependent variable, except for the Communication Scale. The higher effects appeared for Beck Depression Inventory and Social Self-efficacy Questionnaire which presented an effect size of 0,74 and 0,56, respectively. Scores on STAI-A and B and on Self-affirmation Scale were over the effect size’s threshold. However, these improvements don’t attain control group’s scores reported in the scientific literature. DISCUSSION. The results highlighted that our program is effective in reducing difficulties in assertiveness. [less ▲]

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See detailIntegrated management of wild chamomile populations by tillage
Jaunard, Delphine ULg; Monty, Arnaud ULg; Mahy, Grégory ULg et al

in Agricultural and Apllied Biological Sciences (2013, May 21)

Gembloux, Belgium Chemical weeding in agriculture increasingly raises environmental, health and economic preoccupations. European authorities has set up legislations (directive 91/414, settlement 1107 ... [more ▼]

Gembloux, Belgium Chemical weeding in agriculture increasingly raises environmental, health and economic preoccupations. European authorities has set up legislations (directive 91/414, settlement 1107/2009, directive 2009/128) aiming to reduce risks related to the use of pesticides and encouraging integrated pest management. This situation leads professionals and scientists to take interest in the biology and population dynamics of weeds and to study the impacts of integrated pest management on weeds and crops. Tillage can potentially be an efficient weed control method in winter wheat (Triticum aestivum L.). We studied wild chamomile (Matricaria chamomilla L.) population dynamics and crop yields in an experimental winter wheat crop, in relation to tillage methods. Five modalities (i.e. different combinations of a stubble cultivator and/or a moldboard plow, including a no-tillage control) were applied during three years (2009-2012), with four replications, in Gembloux (Belgium). In each plot, M. chamomilla density was recorded throughout the seasons. In summer 2012, wild chamomile density was significantly lower in plots tilled with a moldboard plow. The use of a stubble cultivator did not significantly affect M. chamomilla density. In addition, we found higher wheat yields in ploughed plots, indicating that the decrease in M. chamomilla density reduced competition for wheat. To confirm these results, experiments are still under investigation in similar conditions. [less ▲]

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See detailFumigant toxicity of Mentha pulegium and Citrus aurantium essential oils to Tetranychus urticae (Acari: Tetranychidae) and Phytoseiulus persimilis (Acari: Phytoseiidae)
Attia, Sabrine; Grissa, K.L.; Lognay, Georges ULg et al

in Boeckx; Bossier, Peter; Smagghe, Guy (Eds.) et al Proceedings of the 65th international symposium on crop protection (2013, May 21)

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See detailComparison of parameterization schemes for solving the discrete material optimization problem of composite structures
Duysinx, Pierre ULg; Guillermo Alonso, Maria ULg; Tong, Gao et al

in Halftka, Raphael; KIM, Nam Ho (Eds.) Proceeding of the 10th World Congress on Structural And Multidisciplinary Optimization (2013, May 19)

Optimal design of composite structures can be formulated as an optimal selection of material in a list of different laminates. Based on the seminal work by Stegmann and Lund, the optimal problem can be ... [more ▼]

Optimal design of composite structures can be formulated as an optimal selection of material in a list of different laminates. Based on the seminal work by Stegmann and Lund, the optimal problem can be stated as a topology optimization problem with multiple materials. The research work carries out a large investigation of different interpolation and penalization schemes for the optimal material selection problem. Besides the classical Design Material Optimization (DMO) scheme and the recent Shape Function with Penalization (SFP) scheme by Bruyneel, the research introduces a generalization of the SFP approach using a bi-value coding parameterization (BCP) by Gao, Zhang and Duysinx. The paper provides a comparison of the different parameterization approaches. It also proposes alternative penalization schemes and it investigates the effect of the power penalization. Finally, we discuss the solution aspects in the perspective of solving large-scale industrial applications. The conclusions are illustrated by a numerical application for the compliance maximization of an in-plane composite ply. [less ▲]

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See detailA Lateral sensor for the alignment of two formation-flying satellites
Roose, Stéphane ULg; Stockman, Yvan ULg; Sodnik, Zoran

in Lehmann, Peter H.; Osten, Wolfgang; Albertazzi, Armando (Eds.) SPIE Proceedings Vol. 8788: (2013, May 15)

The lateral sensor is a system able to measure the lateral position between two satellites. It bridges the gap between the alignment accuracy achieved with the radio frequency metrology, and the alignment ... [more ▼]

The lateral sensor is a system able to measure the lateral position between two satellites. It bridges the gap between the alignment accuracy achieved with the radio frequency metrology, and the alignment accuracy required to start the high-precision optical metrology (fine-lateral and longitudinal sensor). This project concerns the demonstration of formation flying technologies for future European scientific and application missions of the EUROPEAN SPACE AGENCY. Technological developments enabling formation flying have already been initiated and some precursor missions already cover part of the related technologies, for example SMART-2. The lateral sensor developed at Centre Spatial de Liège (CSL) is based on a camera (CMOS detector) a telecentric lens designed at CSL, a fibre-coupled laser-diode bar and a corner cube. The fibre-coupled laser-diode bar emits a diverging beam, from the master spacecraft to a slave spacecraft. A corner cube located on the slave spacecraft sends the light back. This light is captured by the telecentric lens and camera (build by Deltatec Liège-B). A lateral shift “d” of the corner cube is seen on the camera as an image displacement. Real time centroidisation algorithms will allow tracking the image position and feed the on-board computer with this information via a RS422 link, allowing further position stabilisation. The imaging system needs to operate in a depth of field from 25 m to 250 m. Because of the large depth of operation, all lateral system performances are angular ones. The system is build to meet: • Tracking capability for a spot moving @ 0.5 arcdeg/sec • Spot detection with the sun in the field of view • Centroidisation accuracy: 0.1 camera pixels (3.5 arcsec) • Absolute calibration accuracy: 0.14 camera pixels (5 arcsec) In order to comply with these requirements, the following features were implemented : • The camera allows quick read-out of sub-windows of interest (in 1 ms). • Optimize radiometric budget and laser diode power consumption, and its related heat dissipation. • An interference filter blocks all unwanted light centred on the laser wavelength (980 nm). • The detector captures the images. An electronic unit records the images and localizes the bright spot (return image from the corner cube). • Implementation of a “slow detection mode”, which allows to discriminate sun from moving image The system is a standalone unit. Once connected to an unregulated 28V power-supply, it delivers, after spot detection, pixel coordinates to the RS422 link at a 10 Hz rate. Its average power consumption is 8W. The system can be put in a programming mode, to allow uploading settings in the FPGA. Tracking, absolute calibration, resolution and sun avoidance have been measured in a field of 10 arcdeg and the range of depth of 5 m to 80 m. The coarse lateral sensor has successfully undergone thermal qualification (40°C and -30 °C), and vibration test (high-level sinus, random and shock test in the 3–axis). Its metrology performances (centroidisation accuracy (<0.1 pixel RMS) and tracking) remained unchanged after these qualification tests. The absolute calibration is 0.3% in the interval of ±5arcdeg (11 arcsec in ±1arcdeg). [less ▲]

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See detailInnovative smart sensors to enhance eco-efficiency of a continuous (steel) production line
Saint-Mard, Michel; Stoukatch, Serguei ULg; Schischke, Karsten et al

in Proc. Conf. of the AMA Association for Sensor Technology (2013, May 15)

The paper aims to demonstrate the benefits for a global approach that allows to define new research directions, new potential industrial markets, and increasing interest from potential users. Combining ... [more ▼]

The paper aims to demonstrate the benefits for a global approach that allows to define new research directions, new potential industrial markets, and increasing interest from potential users. Combining performance, economic and environmental criteria in a joint assessment approach for the target applications of sensor systems, facilitates significantly the communication between service provider and user. The environmental assessment approach for sensor systems will be available as a beta-version online tool tentatively from July 2013 onwards. Interested SMEs are invited to get involved as the LCA to go consortium will provide also a comprehensive mentoring for SMEs [less ▲]

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See detailSynthesis of [18F]4-(4-fluorophenyl)-1,2,4-triazole-3,5-dione: an agent for specific radiolabelling of tyrosine.
Flagothier, Jessica ULg; Warnier, Corentin ULg; Lemaire, Christian ULg et al

in Flagothier, Jessica (Ed.) Journal of Labelled Compounds and Radiopharmaceuticals (2013, May 14)

Objectives: Metal-free and mild tyrosine modification reactions are an attractive alternative to the commonly used lysine and cysteine modification protocols for peptide and proteins labelling. Recently ... [more ▼]

Objectives: Metal-free and mild tyrosine modification reactions are an attractive alternative to the commonly used lysine and cysteine modification protocols for peptide and proteins labelling. Recently, Ban and co-workers have reported a tyrosine bioconjugation through ene-type reactions. Cyclic diazodicarboxamides, which are electrophilic compounds, react selectively in o-position on the phenol side chain of tyrosine in mild aqueous conditions and the 1,2,4-triazolidine-3,5-dione linkage is hydrolytically and thermally stable. We herein present the synthesis of [18F]4-(4-fluorophenyl)-1,2,4-triazole-3,5-dione and the coupling with N-acyl tyrosine methylamide. Methods: The N,N,N-trimethyl-4-nitrobenzeneammonium trifluoromethanesulfonate 1 was prepared following a procedure previously reported [2]. The [18F]prosthetic group 6, [18F]4-(4-fluorophenyl)-1,2,4-triazole-3,5-dione, was synthesized in five steps. Results: The synthesis of the [18F]prosthetic group has been realized with a decay-corrected radiochemical yield of 20% in 90 minutes. The radiochemical yield of the coupling with N-acyl tyrosine methylamide is 40% (DC). This presented synthetic pathway should be easily automated: particulary because the purifications between the different steps are exclusively done on SPE cartridges. Conclusions: We successfully developed an efficient bioconjugation method for fluorine-18 labelling of tyrosine without prior modifications of the peptide in very mild conditions. [less ▲]

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See detailEffects of eccentric versus concentric training on mouse muscle phenotype
Hody, Stéphanie ULg; Lacrosse, Zoé ULg; Leprince, Pierre ULg et al

in Abstract Book of 10th Meeting of Belgian Society for Neuroscience (2013, May)

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See detailThe prognostic value of preoperative FDG PET-CT in hepatocellular carcinoma treated by liver transplantation.
GOVAERTS, L.; DETRY, Olivier ULg; BLETARD, Noëlla ULg et al

in PROCEEDINGS OF THE XVIth SYMPOSIUM OF THE BELGIAN SOCIETY OF NUCLEAR MEDICINE (2013, May)

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See detailCompact integrated surface plasmon resonance spectroscopic sensor platform with on-chip self-referencing
Hastanin, Juriy ULg; Fleury-Frenette, Karl ULg; Lenaerts, Cedric ULg et al

in Proceeding of the International Conference on Surface Plasmon Photonics (SPP6): Ottawa, Canada, May 2013 (2013, May)

We present the SPR_CD spectroscopic biosensor design experimentally investigated by our research group. The implemented sensor platform is dedicated to droplet biochemical analysis involving multichannel ... [more ▼]

We present the SPR_CD spectroscopic biosensor design experimentally investigated by our research group. The implemented sensor platform is dedicated to droplet biochemical analysis involving multichannel detection format. [less ▲]

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See detailPerspectives pour une transition durable des territoires périurbains.
Marique, Anne-Françoise ULg; Reiter, Sigrid ULg

in Journées Aperau : Aménager les métropoles. (2013, May)

L’article traite de la transition durable des territoires périurbains. Deux leviers d’action sont mobilisés à cette fin: (1) la forme urbaine et (2) la mobilité. Trois types de scénarios centrés sur une ... [more ▼]

L’article traite de la transition durable des territoires périurbains. Deux leviers d’action sont mobilisés à cette fin: (1) la forme urbaine et (2) la mobilité. Trois types de scénarios centrés sur une évolution du stock bâti existant sont modélisés et évalués (la rénovation énergétique, la densification et la démolition/reconstruction) de façon à répondre à deux questions : « comment intervenir dans les quartiers périurbains existants? » et « où intervenir? ». Ces simulations montrent que le renouvellement périurbain par densification des quartiers les mieux localisés permet de dépasser le clivage traditionnel entre les modèles de la « ville compacte » et de la « ville diffuse », en offrant de véritables opportunités pour la transition durable des territoires périurbains existants. Ces résultats théoriques, et appréhendés du seul point de vue énergétique, sont ensuite recadrés dans un contexte plus large pour mettre en évidence les opportunités, les limitations, les contraintes et la faisabilité de ces scénarios. [less ▲]

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See detailReview of the Newmark method predicting seismic slope displacements - the focus on the Arias Intensity amplification factor
Torgoev, Almazbek ULg; Havenith, Hans-Balder ULg; Lamair, Laura ULg

in Proceedings of the International Symposium in Commemoration of the 2008 Wenchuan Earthquake (2013, May)

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See detailPlaisir, jeu et écriture dans la déconstruction derridienne
Steinmetz, Rudy ULg

in Les plaisirs et les jours (2013, May)

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See detailUpdate on bone metabolism in premature infants
SENTERRE, Thibault ULg

in 5th International Clinical & Community Nutrition Conference (2013, May)

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See detailLessons from the Liege Acromegaly Survey (LAS)
PETROSSIANS, Patrick ULg; Zacharieva, Sabina; Chanson, Philippe et al

in Endocrine Abstracts - 15 the European Congress of Endocrinology (2013, May)

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See detailImportance of early nutritional support in very low birth weight infants
SENTERRE, Thibault ULg

in 5th International Clinical & Community Nutrition Conference (2013, May)

Detailed reference viewed: 16 (0 ULg)