Détection et localisation d’endommagements structuraux par la méthode des sous-espaces, le modèle de Kalman et la méthode d’analyse en composantes principales
; ; Golinval, Jean-Claude
in Mécanique & Industries (2006), 7
This paper deals with the application of statistical process control techniques for damage diagnosis based on vibration measurements. The first approach considered in this work is based the Stochastic ... [more ▼]
This paper deals with the application of statistical process control techniques for damage diagnosis based on vibration measurements. The first approach considered in this work is based the Stochastic Subspace Identification (SSI) algorithm, from which a Kalman model is constructed to fit the measured response histories of the undamaged (reference) structure. This model may be used to make a prediction of the newly measured responses. The residual error between the model predictions and the actual measurements is defined as a damage-sensitive feature. Outlier statistics provides then a quantitative indicator of damage. The advantage of the method is that model extraction has to be performed only once using the reference data and that no further modal identification is needed. Thus on-line structural health monitoring may easily be realized. In the second approach, principal component analysis (PCA) of the sensor time-responses is used to extract principal directions (i.e. features), which define a subspace that is representative of the dynamics of the instrumented structure. Any change in the response of a single sensor affects the subspace spanned by the complete sensor response set. It follows that the subspace corresponding to the current state of the structure can be compared to the subspace of the initial state of the structure, assumed to be healthy, in order to diagnose possible damage. Principal component analysis may also be performed for every potential subset of damaged sensors in order to identify the involved sensor, and, therefore, the damaged substructure. [less ▲]Detailed reference viewed: 66 (6 ULg)
Effect of sampling method and culture conditions on the result of fungal culture in the diagnosis of canine sino-nasal aspergillosis.
; Clercx, Cécile ; Mignon, Bernard et al
in Proceedings of the 24th VCRS meeting (2006)Detailed reference viewed: 5 (4 ULg)
Les effets sociocognitifs de l’enseignement de la compréhension en première accueil de l’enseignement secondaire : zoom sur le sentiment de progresser
in Caractères (2006), 24(4), 33-39Detailed reference viewed: 5 (2 ULg)
Construction et gestion qualité dans les systèmes de testing
Detroz, Pascal ; Tinnirello, Salvatore
Scientific conference (2006)Detailed reference viewed: 1 (0 ULg)
Comparative study of commercially available anti-alpha-synuclein antibodies.
; ; Deprez, Manuel et al
in Neuropathology & Applied Neurobiology (2006), 32(3), 351-6
Immunohistochemistry for alpha-synuclein has become the histological technique of choice for the diagnosis for Parkinson's disease, Dementia with Lewy bodies and Multiple System Atrophy (http://www.ICDNS ... [more ▼]
Immunohistochemistry for alpha-synuclein has become the histological technique of choice for the diagnosis for Parkinson's disease, Dementia with Lewy bodies and Multiple System Atrophy (http://www.ICDNS.org). Nevertheless, no standardised protocol has been proposed. We have reviewed 242 of the 270 studies published until June 2005 that mentioned immunohistochemistry for anti-alpha synuclein on human tissue and we found that only 75 (31%) used commercial antibodies. We also noted that protocols, particularly dilution and antigen unmasking, varied between studies, even when the same antibody was employed. In order to establish a standardised protocol for alpha-synuclein immunohistochemistry, which can be applied in diagnostic neuropathology we tested seven commercial monoclonal antibodies in brains of subjects with Parkinson's disease, dementia with Lewy bodies, multiple system atrophy, multiple sclerosis with incidental Lewy bodies and aged-matched normal brain and determined for each antibody the best suited protocol for antigen unmasking. We evaluated the intensity of immunolabelling in Lewy bodies, neuropil threads, dendrites, pre-synaptic terminals, granular cytoplasmic positivity, peri-axonal positivity, glial inclusions and non-specific immunolabelling. Although our results showed that all the antibodies detected alpha-synuclein inclusions, differences were noted between antibodies, particularly with regard to the detection of glial inclusions. From our study, the best antibodies of the seven tested appeared to be those directed against amino acids 116-131 and 15-123 and we suggest them to be used in routine diagnostic practice for alpha-synucleinopathies. [less ▲]Detailed reference viewed: 10 (1 ULg)
Comparative assessment of old and new suboptimal control schemes on three example processes
Journee, Michel ; ;
in Proceedings of the 13th IFAC Workshop on Control Applications of Optimisation, Paris (2006)Detailed reference viewed: 4 (2 ULg)
Utiliser le tableur en toute autonomie
Vandeput, Etienne ;
in Pochon, Luc-Olivier; Bruillard, Éric; Maréchal, Anne (Eds.) Apprendre (avec) les progiciels Entre apprentissages scolaires et pratiques professionnelles (2006)
Cet article identifie les invariants des progiciels tableurs dans la perspective d'en enseigner les principes organisateurs essentiels. Dans sa deuxième partie, des exemples plutôt inhabituels d'exercices ... [more ▼]
Cet article identifie les invariants des progiciels tableurs dans la perspective d'en enseigner les principes organisateurs essentiels. Dans sa deuxième partie, des exemples plutôt inhabituels d'exercices liés à la maîtrise de ces invariants sont proposés et commentés. [less ▲]Detailed reference viewed: 37 (5 ULg)
In Vitro Effects Of Water Activity, Temperature And Solutes On The Growth Rate Of P-Italicum Wehmer And P-Digitatum Sacc.
; ; et al
in Journal of Applied Microbiology (2006), 101(3), 628-636Detailed reference viewed: 14 (0 ULg)
Properties of the equine third metacarpal bone as evaluated by axial transmission quantitative ultrasound and quantitative computed tomography – A preliminary study
; Farnir, Frédéric ; et al
Poster (2006)Detailed reference viewed: 14 (0 ULg)
Le statut juridique du migrant en Belgique
in Leleu, Yves-Henri; Dirix, Eric (Eds.) Rapports Belges au Congrès de l'Académie Internationale de Droit comparé à UTRECHT. The Belgian reports at the Congress of Utrecht of the International Academy of Comparative Law. De Belgische rapporten voor het Congres van de "Académie Internationale de Droit comparé" (2006)Detailed reference viewed: 7 (0 ULg)
Animal models of drug addiction: advantages and limitations
in Acta Neurologica Belgica (2006), 106
Various animal models have been developed to investigate the neurobiological and behavioral mechanisms of drug addiction. The most popular of these animal models include the locomotor sensitization ... [more ▼]
Various animal models have been developed to investigate the neurobiological and behavioral mechanisms of drug addiction. The most popular of these animal models include the locomotor sensitization paradigm, the place conditioning procedure and the self-administration technique. With these techniques, it is possible to mimic in rodents the major aspects of human drug addiction. The self-administration procedure is the most widely used and show an excellent natural and predictive validity. In the self-administration protocol, experimental animals, usually rats or mice, are allowed to press a lever in order to gain access to a small dose of an addictive drug. The drug may be given to the animal through the oral, the intravenous or the intracranial route of administration, according to the purpose of the study. In recent years, the classical self-administration procedure has been adapted to study the specific neurobiological basis of drug relapse. In this now called drug reinstatement paradigm, when drug self-administration behaviors are well established, an extinction procedure starts, during which lever pressing is no longer reinforced by drug access. After a number of such extinction sessions, lever pressing gradually declines and eventually stops. Drug-seeking behaviors are therefore said to be extinguished. It is then possible to test various stimuli in order to investigate whether they reinstate drug-seeking behaviors and use such a reinstatement as an animal model of drug relapse. Three types of stimuli have been shown to reinstate drug-seeking behaviors: a small priming dose of drug, drug-associated cues and a stressful stimuli. The effects of these three relapse-triggering stimuli are mediated by different neurobiological mechanisms, leading to the expectation that they may be targeted by different pharmacotherapeutic and behavioral interventions. Despite the high value of the current animal models of drug addiction, there show several limitations. In particular, it is difficult to differentiate between self-controlled and compulsive drug use in animals. As only uncontrolled compulsive drug consumption characterizes drug addiction in humans, such a limitation might explain the high frequency of false positive results in animal experiments. Indeed, it is common that therapeutic interventions successfully developed in animals later proved to be disappointing in humans. [less ▲]Detailed reference viewed: 88 (5 ULg)
Filière et Transformation des conventions professionnelles
Stassart, Pierre M
Conference (2006)Detailed reference viewed: 7 (0 ULg)
Rapport de synthèse : recherche d’indicateurs sédimentaires, diagénétiques et structuraux, prédiction des corps dolomitiques réservoirs: application à la plate-forme carbonatée du Jurassique supérieur (Oxfordien à Portlandien) des Causses Méjean- France. 202p.
; Da Silva, Anne-Christine ; et al
Report (2006)Detailed reference viewed: 7 (2 ULg)
Three dimensional sediment transport model of the Belgian coastal zone: application of the CART theory
Mercier, Christophe ; Delhez, Eric
Suspended sediment processes in the Belgian coastal zone are discussed by presenting the first results given by a 3D coupled hydrodynamic-sediment transport model covering the Southern Bight in North Sea ... [more ▼]
Suspended sediment processes in the Belgian coastal zone are discussed by presenting the first results given by a 3D coupled hydrodynamic-sediment transport model covering the Southern Bight in North Sea. The hydrodynamic sub-model is three-dimensional, baroclinic and includes a refined turbulence closure. In the sediment transport sub-model, the dynamic of sediments is described by an evolution equation of the sediment concentration in the water column and an equation for the sediment load on the seabed. Sedimentation is modeled through the addition of a sedimentation velocity in the vertical advection term. For the evaluation of deposition and erosion terms, formu- lae based on the calculation of the bottom stress under the combined effect of prevailing currents and waves are used. For more realism, sediment loads has also been split into different sediment classes with different sedimentation, deposition and erosion characteristics. The equations are solved by a finite volume method based on an Arakawa C grid, using sigma-transform and mode-splitting numerical methods. The horizontal resolution is 500x500 m and 10 vertical sigma-layers are used. Advection is handled using a TVD scheme with superbee flux limiter. Boundary conditions are provided by coupling this model to a 3D coupled hydrodynamic-sediment transport model of the North-Western European Continental Shelf. The results are validated with measurements carried out by Haecon NV and are compared with those obtained with the MU-STM model. A sensitivity analysis of the model to critical parameters of erosion, deposition and sedimentation based on the concept of residence time was carried out. [less ▲]Detailed reference viewed: 52 (6 ULg)
Mechanobiology and force transduction in scars developed in darker skin types.
Quatresooz, Pascale ; Hermanns, Jean-François ; Paquet, Philippe et al
in Skin Research & Technology (2006), 12(4), 279-82
BACKGROUND: Scarring is a complex process involving many cell types, cytokines and biological pathways including mechanobiology. Some subtle mechanical properties of skin can be assessed by measuring the ... [more ▼]
BACKGROUND: Scarring is a complex process involving many cell types, cytokines and biological pathways including mechanobiology. Some subtle mechanical properties of skin can be assessed by measuring the speed of ultrasound shear wave propagation. The orientation of abnormal skin tension forces can be visualized, particularly in darker skin types, using dermoscopy showing distinct patterns of rete ridges' conformation. AIM: To assess some mechanobiological features of scars in darker skin types. PATIENTS AND METHODS: Large atrophic and hypertrophic surgical scars were examined on the trunk of 35 darker skin subjects. The surrounding skin was used as a comparator. Dermoscopic aspects were recorded. Resonance running time measurements (RRTM) were performed using a shear wave propagation device (Reviscometer). They were performed in four specific directions at given angles with regard to the long axis of the scar. The minimum, maximum and mean RRTM values were recorded at each site. RESULTS: Dermoscopy revealed patterns of melanin deposits in scars distinct from the normal honeycomb network seen in the surrounding skin. Hypertrophic scars showed a patchy pattern of large macular melanoderma dispersed in a lighter background. In these cases, low RRTM values were obtained with little variations according to the orientation of the measurements. By contrast, atrophic scars showed a streaky laddering melanotic pattern under dermoscopy. Higher RRTM values were often obtained, particularly in the transversal direction of the scars. Mechanical anisotropy was greater in the atrophic scars compared with the normal skin. DISCUSSION: Darker skin types represent a model for visualizing the main orientation of the epidermal rete ridges. A correlation was found between the pattern of melanized rete ridges of scars and the main orientation of the intrinsic forces in the skin. [less ▲]Detailed reference viewed: 22 (4 ULg)
L'usage exclusif d'un vaccin inactivé pour la prévention médicale de la maladie d'Aujeszky du chien de chasse
Muylkens, Benoît ; Linden, Annick ; Thiry, Etienne
Article for general public (2006)Detailed reference viewed: 9 (3 ULg)
Iconographies de saints mosans : Munich, Bayerische Staatsbibliothek, Cod. Gall. 3
in Bulletin de la Société Royale Le Vieux-Liège (2006)Detailed reference viewed: 13 (0 ULg)
Dynamic Modelling, Simulation Analysis - Useful for Understanding Biology?
Conference (2006)Detailed reference viewed: 2 (0 ULg)
Why Did it Take so Long to Start a Non-Heart-Beating Donor Program in Belgium ?
in Acta Chirurgica Belgica (2006), 106
The first cadaver kidney transplant, performed in June 1963 in Belgium, was from a heart beating donor (HBD). It was the first ever in the world. Since that period, almost all cadaver organs were procured ... [more ▼]
The first cadaver kidney transplant, performed in June 1963 in Belgium, was from a heart beating donor (HBD). It was the first ever in the world. Since that period, almost all cadaver organs were procured from brain death donors. When the Belgian law on organ donation and transplantation was published on February 1987, with its opting-out principle, no emphasis was placed on procuring organs after cardiac death. Based on the Maastricht experience, in the early nineties, the transplant community interpellated the National Belgian Council of Physicians to facilitate organ procurement in Non-Heart-Beating Donors (NHBD) following the law. But, the transplant community had to wait for the impulse of the first International Congress on NHBD in 1995,where the 4 categories of Maastricht NHBD were defined. It also published 12 Statements and Recommendations which were eventually approved by the European Council. Then all local Ethical Committees received queries for approving local NHBD programs. Almost all centres requested viability testing assessment of the NHBD organ prior to implantation, and proposed the introduction of machine perfusion technology. Finally, all centres joined their efforts and made a collaborative agreement with Organ Recovery Systems for a 24/7 machine perfusion service from a central laboratory. During a three year period (2003-2005), 46 NHBD kidneys were recovered. Among these kidneys, 32 were perfused in the Organ Recovery Systems central laboratory. The Delayed Graft Function (DGF) rate for these perfused kidneys was 25%. Only one graft was lost in this subgroup. Livers, pancreases (for islet preparation) and lungs (for experimental ex-vivo evaluation) were also recovered from these non-heart-beating donors. [less ▲]Detailed reference viewed: 45 (2 ULg)
Nutraceuticals in the management of osteoarthritis: an overview.
in Journal of Veterinary Pharmacology & Therapeutics (2006), 29(Suppl. 1), 201-203Detailed reference viewed: 9 (1 ULg)