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See detailFonck meurt premier comme devant
Bechet, Christophe ULg

E-print/Working paper (2014)

Cet article revient sur le mythe du cavalier Fonck, premier soldat belge tué le 4 août 1914, sur la route Thimister-Battice

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See detailNew Orleans Jazz & Heritage Festival 2014
Sacré, Robert ULg

E-print/Working paper (2014)

Compte rendu du NOLA Jazz & Heritage Festival avril-mai 2014 , avec photos

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See detail3D analysis and determination of stride parameters for different type of foot strike in running
Deflandre, Dorian ULg; Bury, Thierry ULg; Schwartz, Cédric ULg et al

Poster (2014, July)

The purpose of the study was to compare methods for the determination of foot strike and toe off for runners with different foot strike patterns. A 3D optoelectronic system usually used in motion ... [more ▼]

The purpose of the study was to compare methods for the determination of foot strike and toe off for runners with different foot strike patterns. A 3D optoelectronic system usually used in motion laboratories was compared with tools commonly used on the field: an optical based detection system (OptoGait) and an accelerometer based system (Myotest). [less ▲]

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See detailExperimental modal analysis of a beam travelled by a moving mass using Hilbert Vibration Decomposition
Bertha, Mathieu ULg; Golinval, Jean-Claude ULg

Scientific conference (2014, July)

In this paper the problem of modal identification of time-varying system is investigated. To do so, a technique based on the sifting process of the Hilbert Vibration Decomposition (HVD) method is ... [more ▼]

In this paper the problem of modal identification of time-varying system is investigated. To do so, a technique based on the sifting process of the Hilbert Vibration Decomposition (HVD) method is presented. The key idea is to estimate the instantaneous frequency of the dominant mode, to extract its corresponding component by demodulation of the recorded signals and then to iterate with the subsequent dominant mode. In the case of multiple recorded signals, a source separation method is used as a preprocessing step to facilitate the identification of the instantaneous frequency for the following demodulation step. To illustrate the method, an experimental set-up consisting in a beam travelled by a non negligible mass is considered. The whole structure is randomly excited during the travel of the mass and some responses on the beam are recorded. [less ▲]

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See detailWenn Puppen es machen. Eindrücke von der 11. figuma in Eupen (B)
Wunsch-Viehöver, Vera ULg; Wunsch, Stephan

in Das Andere Theater (2014), 24(85),

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See detailReactor mixing angle from hybrid neutrino masses
Aristizabal Sierra, Diego ULg; de Medeiros Varzielas, Ivo

in Journal of High Energy Physics [=JHEP] (2014), 2014(7),

In terms of its eigenvector decomposition, the neutrino mass matrix (in the basis where the charged lepton mass matrix is diagonal) can be understood as originating from a tribimaximal dominant structure ... [more ▼]

In terms of its eigenvector decomposition, the neutrino mass matrix (in the basis where the charged lepton mass matrix is diagonal) can be understood as originating from a tribimaximal dominant structure with small deviations, as demanded by data. If neutrino masses originate from at least two different mechanisms, referred to as "hybrid neutrino masses", the experimentally observed structure naturally emerges provided one mechanism accounts for the dominant tribimaximal structure while the other is responsible for the deviations. We demonstrate the feasibility of this picture in a fairly model-independent way by using lepton-number-violating effective operators, whose structure we assume becomes dictated by an underlying A4 flavor symmetry. We show that if a second mechanism is at work, the requirement of generating a reactor angle within its experimental range always fixes the solar and atmospheric angles in agreement with data, in contrast to the case where the deviations are induced by next-to-leading order effective operators. We prove this idea is viable by constructing an A4-based ultraviolet completion, where the dominant tribimaximal structure arises from the type-I seesaw while the subleading contribution is determined by either type-II or type-III seesaw driven by a non-trivial A4 singlet (minimal hybrid model). After finding general criteria, we identify all the ZN symmetries capable of producing such A4-based minimal hybrid models. [less ▲]

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See detailHigh throughput sequencing analysis reveals genetic variability and selection pressure in different murine norovirus genomic regions during in vitro replication
Mauroy, Axel ULg; Taminiau, Bernard ULg; Nezer, Carine et al

Poster (2014, July)

Murine norovirus (MuNoV), a single stranded positive sense RNA virus belonging to the Caliciviridae family, is considered as a representative model for human norovirus infections, one of the most ... [more ▼]

Murine norovirus (MuNoV), a single stranded positive sense RNA virus belonging to the Caliciviridae family, is considered as a representative model for human norovirus infections, one of the most important etiological cause of both epidemic and sporadic gastroenteritis cases worldwide. Four open reading frames are described into its genome: ORF1 codes the non-structural (NS) proteins, including the viral RNA dependent RNA polymerase (RdRp); ORF2 codes the single capsid protein (VP1), wherein two domains are present: a relatively conserved domain (“shell”) and a more variable domain (“protruding”); ORF3 codes a minor structural protein; and ORF4, currently only found in viruses genetically related to MuNoV codes a virulence factor. In this study, we demonstrated by high throughput sequencing that, during serial passages of MuNoV in cell culture, the substitution rates, estimated by Bayesian inferences, did not significantly differ across the five targeted genomic regions except one. These rates were similar in four genomic regions encompassing partial non-structural 1-2 protein (NS1-2)-, NS5-, NS6-, NS7 (RdRp)- and VP1-coding sequences (coding the conserved part of the protein also including the ORF4 region). In the partial minor structural protein-coding region, this substitution rate was however estimated to be at least one log higher when expressed as substitution/site/day. The precise localisation of the detected nucleotide point mutations (substitution, deletion and insertion) were reported as well as the quantitative increase or decrease of the sequences harbouring them along ten cell culture passages. The non-silent amino acid mutations were also depicted in 3D models for four out of the five studied regions. These results have important implications for different norovirus research fields, especially in terms of diagnosis, classification methodology and genetic evolution. [less ▲]

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See detailEvaluation of process-driven spray retention model on ear-ly growth stage barley
Massinon, Mathieu ULg; Ouled Taleb Salah, Sofiene ULg; De Cock, Nicolas ULg et al

Conference (2014, July)

The efficiency of spray application of foliar plant protection products with hydraulic nozzles on vertically oriented and hydrophobic plants at early growth stages can be very low. The spray retention by ... [more ▼]

The efficiency of spray application of foliar plant protection products with hydraulic nozzles on vertically oriented and hydrophobic plants at early growth stages can be very low. The spray retention by crop leaves is affected by application parameters resulting from nozzle kind, size and operating pressure as well as spray mixture physicochemical properties. When optimizing the spray application, such targets are often used to perform retention trials for comparative purpose, i.e. indoor grown monocotyledonous at two leaves stage. A typical arrangement consists in spraying few plants sufficiently spaced underneath the nozzle to avoid interference due to secondary droplets from impacts on other plants. However, retention trials turn out to ineffective for significantly discriminating between application methods and mixtures due to the high variability between trials resulting from the different droplets retained by each plant. An alternative to retention trials is to tackle spray retention with a physical approach at the droplet scale. Such tests are often performed using high speed imaging with high magnification optics to characterize droplet impacts; adhesion, rebound or shatter on small excised leaf areas and neglect, however, the overall plant architecture. The aim of this paper is to evaluate a droplet interception model connecting actual spray retention with process-driven retention models. In this study, barley plants (BBCH11) were sprayed with 2 formulations using the same nozzle. The actual spray retention was assessed by dosing a fluorescent tracer added to the sprayed mixture. The plants were placed linearly below the center of a single moving nozzle during sprayings. Each plant was reconstructed in 3D afterwards using a structured light 3D scanner and used as input for the model. A virtual nozzle was built on the base of droplet size distributions measured with high speed shadow imaging by performing an adjustment of the distribution by the method of moments. A ran-dom droplet distribution was allocated for each spraying of a barley plant. Droplet velocities were given to droplets on the basis of the droplet velocity – diameter correlation by resolving the droplet transport equations for different droplet sizes. Initial droplet positions were ran-domly given. The interception model is based on a mathematical formalism for the intercep-tion between triangles of the 3D plant and droplet directions. If the droplet impacts a leaf, the amount actually retained by the leaf was computed on the basis of the droplet impact energy and impact behavior from experiments with high speed shadow imaging. In conclusion, the interception model allowed determining the spray retention by plants and discriminating ap-plication parameters by explaining the variability resulting from various droplet size distribu-tions intercepted by single plant. [less ▲]

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See detailEnhancement of ray tracing method for radiative heat transfer with new isocell quasi-monte carlo technique and application to EUI space instrument
Jacques, Lionel ULg; Masset, Luc ULg; Kerschen, Gaëtan ULg

in Proceedings of the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, HEFAT2014 (2014, July)

Monte Carlo ray tracing method for thermal analysis. The rationale for this research is the speed-up of radiative heat transfer computation with the Finite Element Method, widely used in mechanical ... [more ▼]

Monte Carlo ray tracing method for thermal analysis. The rationale for this research is the speed-up of radiative heat transfer computation with the Finite Element Method, widely used in mechanical engineering especially for space structure design but not yet often for thermal analysis of these structures. Based on Nusselt’s analogy, the ray direction sampling is done by sampling the unit disc to derive the ray directions. Stratified sampling is applied to the unit disc that is divided into cells or strata into which random points are generated. The isocell method relies on cells that have the particularity of presenting almost the same area and shape. This enhances the uniformity of the generated quasi-random sequence of ray directions and leads to faster convergence. The isocell method is associated with different surface sampling to derive REFs. The method is benchmarked against ESARAD, the standard ray tracing engine of the thermal analysis software used in the European aerospace industry. Various geometries are used. In particular, one entrance baffle of the Extreme Ultraviolet Imager (EUI) instrument developed at the Centre Spatial de Liège in Belgium is presented. The EUI instrument of the Solar Orbiter European Space Agency mission and will be launched in a 0.28 perihelion orbit around the Sun in 2018. [less ▲]

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See detailTassili n’Ajjer (Sahara Oriental Algérien) – Résultats préliminaires sur le Silurien-Dévonien
Djouder, Hocine ULg; Boulvain, Frédéric ULg; Da Silva, Anne-Christine ULg et al

in Journée Thématique de l’Association des Sédimentologistes Français (ASF) « Diagenèse : avancées récentes et perspectives » (2014, July)

Les gisements atypiques non-conventionnels, à roches sédimentaires faiblement perméables, ainsi que les « sources rocks » constituent une source pétrolière majeure, attirant de plus en plus l’industrie ... [more ▼]

Les gisements atypiques non-conventionnels, à roches sédimentaires faiblement perméables, ainsi que les « sources rocks » constituent une source pétrolière majeure, attirant de plus en plus l’industrie pétrolière, d’où un regain d’intérêt potentiel au sein du Bassin de Berkine. En effet, rien que les argiles radioactives (‘hot’) shales du Silurien sont à l’origine de 80 à 90% des hydrocarbures de la plaque Nord-africaine, et les argiles radioactives du Frasnien (source secondaire) avec des valeurs de TOC allant jusqu’à 14% (Lüning et al., 2000). L'objectif de la thèse s’agira dans un premier temps de l’analyse des diagraphies de forages (Berkine ‘subsurface’) conditionnée aux données de terrain (Tassili n’Ajjer sur affleurements) et de sismique réflexion. Ceci afin de réaliser la modélisation 2D et 3-D des corps réservoirs et de la roche mère, à l’aide du logiciel Petrel©. Et au final, la cartographie des unités de la série Silurien-Dévonien dans le but de définir les « Plays » potentielles aux futures plans d’exploration. Au second volet, la mise au point d’une méthodologie rigoureuse, permettant l’étude minéralogique et l’évolution diagénétique des faciès, sous différents aspect ; la quantification de la porosité, la définition des relations entre porosité et minéralogie. Ensuite caractériser les argiles radioactives du Llandoverien-Frasnien respectivement Silurien, Dévonien et minéraux associés (Lüning et al., 2004). Plus précisément les processus et mécanismes qui contrôlent les transformations des minéraux argileux (minéralogies et cristallochimies) en composante latérale mais aussi en fonction de la profondeur. Dans ce contexte, des missions de terrains seront entreprises dans les massifs du Fadnoun (Tassili Central), Oued Taïni, Oued Khabkhab ainsi que dans l’Oued Amassine (Tassili Occidental) qui nous permettront de décrire en surface les formations du Siluro-Dévonien (profondément étudiées par : Asses, A., 1987 - Massa, D., 1988 - Bekkouche, D., 1992 – IFP, Sonatrach, Beicip., 1999) qui renferment les argiles radioactives (‘hot’) shales et les niveaux réservoirs, situées à quelques centaines de kilomètres au Nord (Bassin de Berkine), sous 2500 à 3000 m de sédiments. Une première mission de terrain est déjà réalisée, ayant reçu un support financier de la R&D (Séjour de Recherche à l’étranger), ainsi que des facilitées administratives et logistiques respectivement du Ministère de la Culture et de l’office national du parc culturel du Tassili n’Ajjer (patrimoine mondial de l’UNESCO depuis 1982). D’autres missions ultérieures seront à organiser en fonction du planning du déroulement de la thèse. La première mission géologique de terrain a duré un mois sur le Plateau de Fadnoun (Tassili n’Ajjer central). Ceci dans différentes coupes géologique-type des affleurements du Silurien-Dévonien : l’Oued Imihrou, l’Oued Farzal, Gara Tihouririne (sur la route Illizi-Fort Tarat) et Isoutar (Djouder et al., 2014). Durant cette mission terrain nous avons pu assurer la concordance entre les thématiques et objectifs de départ et les réalisés sur terrain, entre autre : 1) la meilleure compréhension de la géométrie des corps sédimentaires, au sein du Plateau de Fadnoun et donc par extension dans le bassin ; 2) la description et l’analyse des faciès, grâce aux affleurements peu connus dans les oueds. Ils permettront une analyse, notamment en termes d’environnements sédimentaires, des formations du Silurien-Dévonien ; 3) application première dans son genre de la susceptibilité magnétique comme nouvel proxy, pour les corrélations lithostratigraphiques des unités du Silurien-Dévonien aux Tassilis. 4) réalisation d’un échantillonnage serré à différents niveaux pour couvrir tout l’intervalle de la dépression intra-Tassilienne et des Grès du Tassili Externe, et puis l’expédition du matériel, nécessaire aux analyses de laboratoires notamment à Liège, et collaborateurs. La confection de lames-minces (en cours) permettra l’étude de la minéralogie et de la pétrographie, et donc une meilleure compréhension des faciès et microfaciès, c’est à dire de leurs propriétés intrinsèques (systèmes hétérogènes et complexes). Les lames palynologiques permettront des datations précises de chaque niveau. Enfin, différentes analyses sur roche (minéraux argileux dans un Laboratoire partenaire de l’Université de Poitiers en France, susceptibilité magnétique, cathodoluminescence, analyses géochimiques des majeurs et des traces à l’ULg) permettront d’affiner les paramètres du paléoenvironnement (Da Silva et al., 2013). [less ▲]

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See detailIdentifying codes in vertex-transitive graphs
Gravier, Sylvain; Parreau, Aline ULg; Rottey, Sara et al

Conference (2014, July)

We consider the problem of computing identifying codes of graphs and its fractional relaxation. The ratio between the optimal integer and fractional solutions is between 1 and 2 log(|V|) where V is the ... [more ▼]

We consider the problem of computing identifying codes of graphs and its fractional relaxation. The ratio between the optimal integer and fractional solutions is between 1 and 2 log(|V|) where V is the set of vertices of the graph. We focus on vertex-transitive graphs for which we can compute the exact fractional solution. There are known examples of vertex-transitive graphs that reach both bounds. We exhibit infinite families of vertex-transitive graphs with integer and fractional identifying codes of order |V|^a with a in {1/4, 1/3, 2/5}. These families are generalized quadrangles (strongly regular graphs based on finite geometries). They also provide examples for metric dimension of graphs. [less ▲]

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See detailDonor age as a risk factor in donation after circulatory death liver transplantation in a controlled withdrawal protocol programme.
DETRY, Olivier ULg; DE ROOVER, Arnaud ULg; MEURISSE, Nicolas ULg et al

in The British journal of surgery (2014), 10(7), 784-792

BACKGROUND: Results of donation after circulatory death (DCD) liver transplantation are impaired by graft loss, resulting mainly from non-anastomotic biliary stricture. Donor age is a risk factor in ... [more ▼]

BACKGROUND: Results of donation after circulatory death (DCD) liver transplantation are impaired by graft loss, resulting mainly from non-anastomotic biliary stricture. Donor age is a risk factor in deceased donor liver transplantation, and particularly in DCD liver transplantation. At the authors' institute, age is not an absolute exclusion criterion for discarding DCD liver grafts, DCD donors receive comfort therapy before withdrawal, and cold ischaemia is minimized. METHODS: All consecutive DCD liver transplantations performed from 2003 to 2012 were studied retrospectively. Three age groups were compared in terms of donor and recipient demographics, procurement and transplantation conditions, peak laboratory values during the first post-transplant 72 h, and results at 1 and 3 years. RESULTS: A total of 70 DCD liver transplants were performed, including 32 liver grafts from donors aged 55 years or less, 20 aged 56-69 years, and 18 aged 70 years or more. The overall graft survival rate at 1 month, 1 and 3 years was 99, 91 and 72 per cent respectively, with no graft lost secondary to non-anastomotic stricture. No difference other than age was noted between the three groups for donor or recipient characteristics, or procurement conditions. No primary non-function occurred, but one patient needed retransplantation for artery thrombosis. Biliary complications were similar in the three groups. Graft and patient survival rates were no different at 1 and 3 years between the three groups (P = 0.605). CONCLUSION: Results for DCD liver transplantation from younger and older donors were similar. Donor age above 50 years should not be a contraindication to DCD liver transplantation if other donor risk factors (such as warm and cold ischaemia time) are minimized. [less ▲]

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See detailOptimization Of A Heat Pump For Satellite Cooling
Bell, Ian ULg; Lemort, Vincent

in 15 th International Refrigeration and Air Conditioning Conference at Purdue (2014, July)

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See detailThe concept of economic security of the hospital: A new look at the levers of control
Shutyak, Yuliya ULg; Van Caillie, Didier ULg

Conference (2014, July)

Despite a significant progress achieved in the healthcare sector during last decades, we need to admit the fact that many urgent problems remain unsolved even in well developed countries. Along with other ... [more ▼]

Despite a significant progress achieved in the healthcare sector during last decades, we need to admit the fact that many urgent problems remain unsolved even in well developed countries. Along with other major factors, economic causes of these problems hold a prominent position. It is then necessary to think about a need of shifting from a view of hospitals as ever being institutions existing by default in any society to a view of hospitals as organisations with an incorporated economic mechanism, adapted to social changes and relevant economic risks. With this regard, this paper seeks to incorporate the concept of economic security of the hospital into Simons’ LOC model used in hospital management. We provide a brief overview of the concept of economic security of the organization. We adjust this concept for hospital management considering the healthcare system as an economic system and taking main problems of the hospital and interests of stakeholders in the core of strategy development. Further, we accommodate the concept with the levers of control. The result of the paper is a revised Simons’ LOC model which provides a theoretical framework for further research on hospital management and serves a modified management instrument. [less ▲]

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See detailRisk assessment of soil compaction in Walloon Region
D'Or, Dimitri; Destain, Marie-France ULg

in Proceedings of geoENV2014 (2014, July)

It is well established that soil compaction affects the growth and functioning of roots and disrupts the activity of microfauna and soil microorganisms, resulting in a loss of yields. Agriculture and ... [more ▼]

It is well established that soil compaction affects the growth and functioning of roots and disrupts the activity of microfauna and soil microorganisms, resulting in a loss of yields. Agriculture and forestry using increasingly heavy machines, the risk of soil compaction is increasing accordingly. Chosen as indicator of the susceptibility of soils to compaction, the precompression stress (Pc) is calculated using the pedotransfer functions (PTFs) proposed by Horn and Fleige (2003). These PTFs involve eight parameters linked to the hydraulic and mechanical behaviour of soils: organic matter content, bulk density, air capacity, available and non-plant available water capacity, saturated hydraulic conductivity, cohesion and angle of internal friction. The challenge consists in producing Pc maps at the regional scale for Wallonia. Those maps should also be accompanied by estimation uncertainty map. Finally, the results should be exploited to produce compaction risk maps according to various frequent scenarios. In this paper, a methodology is proposed, combining geostatistics and Monte Carlo simulations, to achieve these goals. [less ▲]

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See detailFascination as a Case of Action at a Distance in Early Modern Science
Dubouclez, Olivier ULg

Conference (2014, July)

BUCHAREST-PRINCETON SEMINAR IN EARLY MODERN PHILOSOPHY 14th Edition Organized by the Research Centre for the Foundations of Modern Thought (FME), University of Bucharest, in collaboration with the ... [more ▼]

BUCHAREST-PRINCETON SEMINAR IN EARLY MODERN PHILOSOPHY 14th Edition Organized by the Research Centre for the Foundations of Modern Thought (FME), University of Bucharest, in collaboration with the Philosophy Department at Princeton University 8 – 13 July 2014 Bran, Romania De rerum natura: Naturalism, Super-naturalism, Unnaturalism Invited speakers include: Daniel Garber (Princeton University), Roger Ariew (University of South Florida), Igor Agostini (Università del Salento), Peter Anstey (University of Sydney), Olivier Dubouclez (Université de Liège), Tamás Pavlovits (University of Szeged), Jennifer Rampling (Princeton) Description : https://ci3.googleusercontent.com/proxy/8CBWEZYl_gju-O0mEKjDNw0Eh_qIbYUu1oZBKfZqOypmLO1gU9NfBBUnKK5HrwoN-VKG8iQn_PvQpZDlbxq0IwVL9dQOy_HcGJ0=s0-d-e1-ft#https://mail.google.com/mail/u/0/images/cleardot.gif Some Seventeenth Century authors gave a new definition of nature, clearly articulated in terms of natural laws and of their dependence on God. Even if some elder tensions, coming from the Stoic and Epicurean heritage, were thus released, new challenges appeared, related to the limits of nature (is the world finite or infinite?), the structure of matter, the status of the mind and the status of the human being with respect to nature. While some philosophers as Bruno, Telesio and Cardano tried to reach a compromise with Renaissance vitalism, promoting a natural magic and a new alchemy, some others, such Bacon, Descartes, Spinoza, Leibniz, proposed radical different paths. Not losing sight of the manner in which ancient thought (Pliny and Lucretius seem to be naturally summoned) informed modern debate over nature, the seminar will try to uncover a period in which Spinoza could articulate his critique of Descartes as holding a view of man as "imperium in imperio". The Bucharest-Princeton Seminar in Early Modern Philosophy is an international annual meeting of scholars interested in various aspects of early modern thought. The aim of the seminar is to create a stimulating environment for discussing papers and ideas. It includes workshops in the morning and presentations of papers in the afternoon, where participants can present work in progress. While the morning sessions will focus on the theme of “De rerum natura: Naturalism, Super-naturalism, Unnaturalism,” the afternoon sessions seek to give participants an opportunity to discuss their own special interests with an open and sympathetic audience of students and scholars with broad interests in early modern thought. Throughout we try to maintain a balance between the high scholarly level and the informal friendly spirit of a colloquium. The Seminar will take place in Bran, a small mountain resort near Brasov, in Transylvania. It will be hosted in a small, friendly Bed and Breakfast (single or double rooms). The participation fee is 150 EUR for faculty and 90 EUR for students (covering accommodation with breakfast). We invite applications for contributions (from researchers) and for attendance (from students). If you want to contribute a paper, please send a CV and a one-page abstract, and if you want to attend, a CV and a letter of intent – by April 20 – to Vlad Alexandrescu (valexandrescu@gmail.com), Dana Jalobeanu (dana.jalobeanu@celfis.ro). [less ▲]

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See detailAdvanced Aeroservoelastic Modeling for Horizontal axis Wind Turbines
Prasad, Chandra Shekhar ULg; Chen, Qiong-zhong; Dimitriadis, Grigorios ULg et al

in Cunha, A.; Caetano, E.; Riberio, P. (Eds.) et al Proceedings of the 9th International Conference on Structural Dynamics, EURODYN 2014 (2014, July)

This paper describes the development of a complete methodology for the unsteady aeroelastic and aeroservoelastic modeling of horizontal axis wind turbines at the design stage. The methodology is based on ... [more ▼]

This paper describes the development of a complete methodology for the unsteady aeroelastic and aeroservoelastic modeling of horizontal axis wind turbines at the design stage. The methodology is based on the implementation of unsteady aerodynamic modeling, advanced control strategies and nonlinear finite element calculations in the S4WT wind turbine design package. The aerodynamic modeling is carried out by means of the unsteady Vortex Lattice Method, including a free wake model. The complete model also includes a description of a doubly fed induction generator and its control system for variable speed operation and enhanced power output. The S4WT software features a non-linear finite element solver with multi-body dynamics capability. The complete methodology is used to perform complete aeroservoelastic simulations of a 2MW wind turbine prototype model. The interaction between the three components of the approach is carefully analyzed and presented here. [less ▲]

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See detailUpdate on investigation in IPF - Clinical presentation and epidemiology in domestic animals
Clercx, Cécile ULg

in Proceedings of the Fibrosis Across Species Consortium - Louisville - EU - 27th – 29th April 2014 (2014, July)

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See detailEvent-driven integration of linear structural dynamics models under unilateral elastic constraints
Depouhon, Alexandre ULg; Detournay, Emmanuel; Denoël, Vincent ULg

in Computer Methods in Applied Mechanics & Engineering (2014), 276

This paper proposes an algorithm for the numerical simulation of linear structural dynamics problems under unilateral elastic constraints, i.e., constraints with a linear force/displacement characteristic ... [more ▼]

This paper proposes an algorithm for the numerical simulation of linear structural dynamics problems under unilateral elastic constraints, i.e., constraints with a linear force/displacement characteristic whenever active. The presented procedure relies on an event-driven strategy for the handling of the contact constraints, in combination with one-step schemes dedicated to the time integration of the second-order equations of motion. Efficiency of the procedure follows from the use of cubic Hermite interpolation to continuously extend the normal gap functions that reflect the openings of the contact interfaces. Robustness follows from the proper handling of complex numerical situations, e.g., numerical grazing or discontinuity sticking, through appropriate algorithm structure and numerical implementation. And, integration stability is guaranteed by the very nature of the algorithm and that of the one-step integration scheme. Following a detailed coverage of the integration procedure and the countermeasures to the expected numerical difficulties, three application examples are treated for illustration purposes. A MATLAB implementation of the procedure is provided online; download and usage information are given in the Appendix. [less ▲]

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See detailExcavation damaged zone modelling including hydraulic permeability evolution in unsaturated argilaceous rock
Pardoen, Benoît ULg; Levasseur, Séverine ULg; Collin, Frédéric ULg

in 6th International Conference on Unsaturated Soils (2014, July)

The drilling of galleries induces damage propagation in the surrounding medium and creates the Excavation Damaged Zone (EDZ) in which the material properties are modified. The prediction of the fracture ... [more ▼]

The drilling of galleries induces damage propagation in the surrounding medium and creates the Excavation Damaged Zone (EDZ) in which the material properties are modified. The prediction of the fracture structure and flow properties evolution within this zone are major issues especially in the context of underground nuclear waste storage. Since experimental results indicate that shear strain localisation appears prior to fractures, we model the EDZ with strain localisation in shear band mode using the coupled local second gradient model. The evolution of the intrinsic hydraulic permeability inside the fractures is taken into consideration as well as the influence of gallery ventilation on the rock desaturation. The numerical results provide information about the damaged zone extension, structure and behaviour with good correspondence to in situ measurements and observations. [less ▲]

Detailed reference viewed: 72 (23 ULg)