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See detailLe design du système de contrôle de gestion dans les PMI tunisiennes: une modélisation contingente
Ghorbel, Jihene ULg; Van Caillie, Didier ULg

E-print/Working paper (2012)

A l'heure actuelle, il existe relativement peu de recherches qui traitent du système de contrôle de gestion des PME, spécialement dans le contexte tunisien, malgré leur importance économique. La présente ... [more ▼]

A l'heure actuelle, il existe relativement peu de recherches qui traitent du système de contrôle de gestion des PME, spécialement dans le contexte tunisien, malgré leur importance économique. La présente communication vise dès lors à élaborer un modèle théorique expliquant le design du système de contrôle de gestion dans les PMI tunisiennes, au départ d'une analyse de la littérature portant spécifiquement soit sur les PMI tunisiennes, soit sur le système de contrôle de gestion de la PME. Cette étude est réalisée en privilégiant deux angles d'analyse particulièrement importants au vu du contexte tunisien, à savoir la taille de l'entreprise et son positionnement sur le cycle de vie. [less ▲]

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See detailLe design du système de contrôle de gestion des PME : une quête de stabilité adaptative
Van Caillie, Didier ULg; Santin, Sarah; Rouhana, Rima ULg

in Actes du XXIIIème Congrès de l'Association Francophone de Comptabilité (2008, May)

This paper discusses the characteristics of management control systems in SMEs and insists on their ability to monitor change and performance in high turbulent environment

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See detailDesign et évaluation de nouveaux biomatériaux pour la construction de tissus
Grandfils, Christian ULg

Conference (2011, January 19)

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See detailDesign et synthèse de nouveaux dérivés coumariniques inhibiteurs de thrombine
Frederick, R.; Pochet, L.; Pirotte, Bernard ULg et al

Poster (2002, May 31)

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See detailDesign for a multi-channel recording and stimulation device
Dethier, Julie ULg

Master's dissertation (2010)

Brain functions can be severely altered by accidents leading to traumatic brain injuries or by diseases such as strokes, cancers or Alzheimer's. Currently, there are no medical instruments capable of ... [more ▼]

Brain functions can be severely altered by accidents leading to traumatic brain injuries or by diseases such as strokes, cancers or Alzheimer's. Currently, there are no medical instruments capable of restoring cognitive function, but recent progress in neurophysiology coupled with development of engineering techniques has introduced the era of a new class of devices: neural prostheses or brain-computer interfaces (BCIs). BCIs carry great promises: possibilities to stimulate areas of the brain to prevent or treat failures of the nervous system. Today, most devices used in this domain are not capable of restricting their action to specified anatomical targets due to the large size of the electrodes. In 2007, the BES-group (imec, Leuven) developed silicon-based multi-electrode neural probe arrays interacting at a single neuron level (single-unit) for in vivo selective neuronal recording and stimulation. My Master Thesis was developed with imec, Leuven, and focused on the realization of a multi-channel recording system for neural applications to enable a closed-loop approach (recording - stimulation - recording) that would allow for adjustment and fine tuning of the required stimulation pattern. The system’s read-out conditions and digitizes eight channels and provides the digitized output to an existing TI MSP430 based microprocessor system for wired or wireless data handling. The resulting platform can be used as a prototype for extensive experimental testing by biomedical scientists from the BES-group (imec). The first step in the study is the analysis, from a theoretical standpoint, of the conditioning and digitalization of the signals: low-noise amplification, filtering, offset compensation and digitization. A signal-to-noise study is performed, leading to the selection of electronic components suitable for my project. In the second part of the work, the PCB layout is conceived in a miniaturized SMD design style. The code implemented in the microprocessor MSP430 is detailed both for the recording of a single channel and eight channels concurrently. Adaptation of the amplification factor can be carried out either by digital processing or by user interaction. Design of the wireless link between a PC and the board is then considered. The link is built from the eZ430-RF2500 Development Tool (Texas Instruments), a complete USB-based wireless development tool providing all the hardware and software to create a wireless network. Eventually, the performance and limitations of the design are evaluated. The system handles properly the entire frequency range of action potentials (from 100Hz to 6kHz) for both wired and wireless configurations and shows very good results for signals with amplitude higher than 1mV_pp. Gain variation is available with either a stand-alone digital processing method or with user's control through keyboard and achieves satisfactory results for both accuracy and rapidity. The major limitation is a lack of accuracy for signals below 500〖μV〗_pp. Solutions for future designs are proposed including suppression of the offset compensation circuit and acceleration of the communication with the computer. Ideas for the addition of stimulation functions are proposed in hopes of a closed-loop approach. Last but not least, power supply and dissipation considerations are tackled. [less ▲]

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See detailDesign for an Ipriflavone Multicenter European Fracture Study
Reginster, Jean-Yves ULg; Bufalino, L.; Christiansen, C. et al

in Calcified Tissue International (1997), 61(Suppl 1), 28-32

In order to investigate the efficacy of ipriflavone (i.p.) on the prevention of vertebral fractures and the effect on bone mineral density (BMD) in women with postmenopausal osteoporosis, a large ... [more ▼]

In order to investigate the efficacy of ipriflavone (i.p.) on the prevention of vertebral fractures and the effect on bone mineral density (BMD) in women with postmenopausal osteoporosis, a large multicentric European study was designed and is presently ongoing. Included in the study were 460 Caucasian, nonobese postmenopausal women aged > 45 and < 75 years, menopaused for at least 12 months. Inclusion was on the basis of a lumbar bone mineral density (BMD) lower than 2 SD compared with healthy women aged 50 years, corresponding to values below 0.860 g/cm2 (antero-posterior measurement) by Hologic QDR 1000. Women with prevalent vertebral fractures were excluded as well as those presenting secondary osteoporosis or having been treated with medications that could affect bone metabolism. This study was designed as a 3-year, double-blind, placebo-controlled, parallel group study that randomized the women to the oral administration of either 3 x 200 mg/day of i.p. or placebo. All patients received a daily supplement of 500 mg calcium. The primary purpose of the study was to evaluate the efficacy of i.p. in preventing vertebral nontraumatic fractures. Fracture is defined here as a > or = 20% decrease in any anterior, central, or posterior T4-L4 vertebral height. Blinded vertebral X-ray readings and vertebral morphometry have been centralized in an independent Center, with standardized evaluation of two experts. Power calculations have been based on the hypothesis that 21% of placebo-treated patients would fracture within 3 years and that treatment with i.p. would lead to a 50% reduction in the incidence of fracture. Statistical tests have been designed to have a power of 80%, with a type I error equal to 5%. Secondary endpoints were changes in vertebral, radial, and femoral BMD. Centralized controls on 100% BMD scans would ensure the good quality of BMD readings. This study should verify the hypothesis that i.p. significantly decreases the risk of vertebral fracture in postmenopausal, osteoporotic women. [less ▲]

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See detailA design for living: metaleptic devices and trends of gnostic imagination in contemporary science-fiction
Claisse, Frédéric ULg

Conference (2012, October)

As a narrative pattern and a cultural motif, the confusion between fictional worlds and reality traditionally leads to metaphysical arguments about liberty and destiny. Despite their drawing heavily on ... [more ▼]

As a narrative pattern and a cultural motif, the confusion between fictional worlds and reality traditionally leads to metaphysical arguments about liberty and destiny. Despite their drawing heavily on scientific imagination and technoscientific artefacts, science fiction movies exploring that theme never really broke with the way it has been treated since Calderon de la Barca’s Life is a dream: the hero’s quest leads him to doubt his own identity and dispute the ontological status of the world he lives in, leaving him and the viewer perplexed as to the ultimate nature of things. Yet, in the last fifteen years, an increasing number of science-fiction movies renewed that interrogation, notably by placing the issue of design at the centre of the plot: fictional worlds are not only denounced as fictional, but also shown as works in progress, literally rebuilt according to the plan of not-so-hidden designers acting as demiurges. In Dark City, Vanilla Sky or, more recently, Inception and The Adjustment Bureau, the emphasis on design and architecture together with the use of computational metaphors result in the promotion of one particular world to the status of “reference” universe, to be held as more “real” than other, fabricated and computed worlds made accessible by sophisticated devices operating as metaleptic instruments (such as Neo’s cable plug or the “bio-ports” in ExistenZ). This paper wishes to explore this shift towards “gnostic", Matrix-like science-fictional narratives, particularly in relation to the dramatic development of networking and surveillance capabilities that occurred during the same period. [less ▲]

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See detailDesign for polarizing holographic optical elements
Habraken, Serge ULg; Renotte, Yvon; Roose, Stéphane ULg et al

in Applied Optics (1995), 34(19), 3595-3602

We present results of the application of a three-dimensional rigorous-vector coupled-wave theory to the design of polarizing holographic optical elements. Two different cases have been selected giving ... [more ▼]

We present results of the application of a three-dimensional rigorous-vector coupled-wave theory to the design of polarizing holographic optical elements. Two different cases have been selected giving rise to two types of element, one of which is completely original. Experimental realizations were performed. The recording material was dichromated gelatin because of its outstanding performance related to diffraction efficiency. A fair agreement between the theoretical previsions and the experimental results was achieved. [less ▲]

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See detailDesign guidelines for construction of energy efficient buildings in North-East India
Singh, Manoj Kumar ULg; Mahapatra, Sadhan

Scientific conference (2006, February)

Energy and Built Environment are closely related, the more is the energy consumption the worse is the environment degradation. The use of natural lighting and the use of solar energy for heating and ... [more ▼]

Energy and Built Environment are closely related, the more is the energy consumption the worse is the environment degradation. The use of natural lighting and the use of solar energy for heating and cooling as well as enhanced natural ventilation not only reduce the commercial energy demand but minimize the impact on environment too. Traditional buildings constructed long back in the different climatic zones of the region have a number of passive features which help in controlling the indoor environment mostly by promoting ventilation, as humidity level is alarmingly high in this region. There are exhibits of indigenous use of locally available materials and techniques to construct buildings that are adapted to local climatic conditions or even to the ethnicity of the community. Guidelines are prepared taking into consideration the different features like site, orientation & planform, building envelope and daylight for low-rise residential buildings; since these are very common in this region. [less ▲]

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See detailDesign guidlines - Deliverable D.13 - Robustimpact
Charlier, Marion; Hanus, François; Vassart, Olivier et al

Report (2016)

The present document details the design guidelines which emanates from the RobustImpact project. The reasoning used is depicted below in Figure 1-1. The first step is to define the impact scenario and its ... [more ▼]

The present document details the design guidelines which emanates from the RobustImpact project. The reasoning used is depicted below in Figure 1-1. The first step is to define the impact scenario and its key parameters. Then the impact can be characterized as a hard impact or as a soft impact. The first option assumes that the kinetic energy of the impactor is absorbed by the impactor itself while the second option assumes that the kinetic energy of the impactor is mainly absorbed by the column, thus leading to plastic deformations and the activation of geometrical non-linear effects in the column. If the soft impact is considered, the buckling resistance of the column must be examined in order to evaluate if the impacted column shows sufficient residual resistance after the impact. If this is not the case, the structure will resist if it is able to sustain the load initially carried by the impacted column by redistributing it in the damaged structure, i.e. if it is able to activate alternative load path. The resistance brought by other structural elements will then be evaluated. If the impacted column is a peripheral column, the yield line theory is used to evaluate the resistance of both slab and beams. In case of a central column, Bailey’s method evaluating the slab resistance taking into account the membrane effect is used to determine the contribution of the slab. The contribution of the beams is then quantified by evaluating the corresponding P-u curve. All the methods have been validated using FEM softwares. Since the project concerns structures whose columns are impacted by vehicles, the accidental load combination must be considered. In addition, the yield strength of the steel should be considered as 𝑓𝑦,𝑑𝑦𝑛= 𝜇.𝑓𝑦> 𝑓𝑦 . Indeed was proved than the steel mechanical properties are better under dynamic loading. Nevertheless, there is for the moment no available quantification for the majoring coefficient that should apply to 𝑓𝑦 : this could be done realizing tests. [less ▲]

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See detailDesign handbook for frame design including joint behaviour
Jaspart, Jean-Pierre ULg; Maquoi, René ULg

in Proceedings of the First Annual Workshop, Targeted Research Action of the European Communities on Environmentally Friendly Construction Technologies (1997)

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See detailDesign handbook for frame design including joint behaviour
Jaspart, Jean-Pierre ULg; Maquoi, René ULg

in Proceedings of the IABSE Colloquium on Semi-Rigid Structural Connections (1996)

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See detailDesign Method for Subsonic and Transonic Cascade with Prescribed Mach Number Distribution
Léonard, Olivier ULg; Van den Braembussche, René

in Proceedings of the ASME Turbo Expo 1991 (1991, June)

A iterative procedure for blade design, using a time marching procedure to solve the unsteady Euler equations in the blade-to-blade plane, is presented. A flow solver, which performs the analysis of the ... [more ▼]

A iterative procedure for blade design, using a time marching procedure to solve the unsteady Euler equations in the blade-to-blade plane, is presented. A flow solver, which performs the analysis of the flow field for a given geometry, is transformed into a design method. This is done by replacing the classical slip condition (no normal velocity component) by other boundary conditions, in such a way that the required pressure or Mach number distribution may be imposed directly on the blade. The unknowns are calculated on the blade wall using the so-called compatibility relations. Since the blade shape is not compatible with the required pressure distribution, a nonzero velocity component normal to the blade wall evolves from the new flow calculation. The blade geometry is then modified by resetting the wall parallel to the new flow field, using a transpiration technique, and the procedure is repeated until the calculated pressure distribution has converged to the required one. Examples for both subsonic and transonic flows are presented and show a rapid convergence to the geometry required for the desired Mach number distribution. An important advantage of the present method is the possibility to use the same code for the design and the analysis of a blade. [less ▲]

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See detailDesign Method for Subsonic and Transonic Cascade with Prescribed Mach Number Distribution
Léonard, Olivier ULg; Van den Braembusche, René

in Journal of Turbomachinery (1992), 114(3), 553-560

An iterative procedure for blade design, using a time marching procedure to solve the unsteady Euler equations in the blade-to-blade plane, is presented. A flow solver, which performs the analysis of the ... [more ▼]

An iterative procedure for blade design, using a time marching procedure to solve the unsteady Euler equations in the blade-to-blade plane, is presented. A flow solver, which performs the analysis of the flow field for a given geometry, is transformed into a design method. This is done by replacing the classical slip condition (no normal velocity component) by other boundary conditions, in such a way that the required pressure or Mach number distribution may be imposed directly on the blade. The unknowns are calculated on the blade wall using the so-called compatibility relations. Since the blade shape is not compatible with the required pressure distribution, a nonzero velocity component normal to the blade wall evolves from the new flow calculation. The blade geometry is then modified by resetting the wall parallel to the new flow field, using a transpiration technique, and the procedure is repeated until the calculated pressure distribution has converged to the required one. Examples for both subsonic and transonic flows are presented and show a rapid convergence to the geometry required for the desired Mach number distribution. An important advantage of the present method is the possibility to use the same code for the design and the analysis of a blade. [less ▲]

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See detailDesign Methods
Rigo, Philippe ULg; Karr, D.; Comité IV.2, ISSC

in Report of the Technical Committee IV.2 of ISSC (2009)

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See detailDESIGN METHODS Report of Technical Committee IV.2 of ISSC
Pradillon, Jean Yves; Rigo, Philippe ULg; ISSC IV.2 Commiteee

in 18th INTERNATIONAL SHIP AND OFFSHORE STRUCTURES CONGRESS (ISSC) (2012)

Concern for the synthesis of the overall design process for marine structures, and its integration with production, maintenance and repair. Particular attention shall be given to the roles and ... [more ▼]

Concern for the synthesis of the overall design process for marine structures, and its integration with production, maintenance and repair. Particular attention shall be given to the roles and requirements of computer-based design and production, and to the utilization of information technology. [less ▲]

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See detailDesign Monopile Foundation of Offshore Wind Turbines
Mai, Anh Quang ULg

Master's dissertation (2012)

Design optimization is crucial to the development of the offshore wind turbine industry. This time consuming process is better to be done with a number of input parameters that is as short as possible ... [more ▼]

Design optimization is crucial to the development of the offshore wind turbine industry. This time consuming process is better to be done with a number of input parameters that is as short as possible. Whether the foundation pile part can be neglected in the design optimization process of an offshore wind turbine structure is a question need to be answer. In order to see the importance of the presence of the foundation pile in dynamic behavior of the whole structure, dimensions of the foundation pile must be determined basing on requirements in ultimate limit state and serviceability limit state in current design standards. Afterward, the differences in dynamic behavior between a fixed- at-seabed tower model and a tower with foundation model must be observed. Beam nonlinear Winkler Foundation model in addition to gapping and non-gapping behavior in pile-soil interface were used to model the foundation. With the chosen offshore wind turbine project of 7MW and 115m high to seabed, a foundation pile with a penetration length of 26m, diameter of 6m and wall thickness of 8cm had been found. The dynamic behavior of the two models showed that it was not on the safe side if the foundation was neglected in design optimization process. And that the internal damping of the soil was the most important factor in behavior of the structure. These results will be useful for reconsidering parameters in design optimization process of monopile offshore wind turbines as well as choosing suitable methods to solve dynamic equations in the optimization procedure. [less ▲]

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