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See detailDesign and tests for the heliospheric imager of the STEREO mission
Defise, Jean-Marc ULg; Halain, Jean-Philippe ULg; Mazy, Emmanuel ULg et al

in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (2002)

The Heliospheric Imager (HI) is part of the SECCHI suite of instruments on-board the two STEREO spacecrafts to be launched in 2005. The two HI instruments will provide stereographic image pairs of solar ... [more ▼]

The Heliospheric Imager (HI) is part of the SECCHI suite of instruments on-board the two STEREO spacecrafts to be launched in 2005. The two HI instruments will provide stereographic image pairs of solar coronal plasma and coronal mass ejections (CME) over a wide field of view (~90°), ranging from 13 to 330 R[SUB]0[/SUB]. These observations compliment the 15 R[SUB]0[/SUB] field of view of the solar corona obtained by the other SECCHI instruments (2 coronagraphs and an EUV imager). The key challenge of the instrument design is the rejection of the solar disk light, with total straylight attenuation of the order of 10[SUP]-13 [/SUP]to 10[SUP]-15[/SUP]. A multi-vane diffractive baffle system has been theoretically optimized to achieve the lower requirement (10[SUP]-13[/SUP] for HI-1) and is combined with a secondary baffling system to reach the 10[SUP]-15[/SUP] rejection performance in the second camera system (HI-2). This paper presents the last updates of the SECCHI/HI design concept, with the expected performance. A verification program is currently in progress. The on-going stray-light verification tests are discussed. A set of tests has been conducted in air, and under vacuum. The results are presented and compared with the expected theoretical data. [less ▲]

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See detailDesign and tests for the heliospheric imager of the STEREO mission
Defise, Jean-Marc ULg; Halain, Jean-Philippe ULg; Mazy, Emmanuel ULg et al

in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (2003, February 01)

The Heliospheric Imager (HI) is part of the SECCHI suite of instruments on-board the two STEREO spacecrafts to be launched in 2005. The two HI instruments will provide stereographic image pairs of solar ... [more ▼]

The Heliospheric Imager (HI) is part of the SECCHI suite of instruments on-board the two STEREO spacecrafts to be launched in 2005. The two HI instruments will provide stereographic image pairs of solar coronal plasma and coronal mass ejections (CME) over a wide field of view (~90°), ranging from 13 to 330 R[SUB]0[/SUB]. These observations compliment the 15 R[SUB]0[/SUB] field of view of the solar corona obtained by the other SECCHI instruments (2 coronagraphs and an EUV imager). The key challenge of the instrument design is the rejection of the solar disk light, with total straylight attenuation of the order of 10[SUP]-13 [/SUP]to 10[SUP]-15[/SUP]. A multi-vane diffractive baffle system has been theoretically optimized to achieve the lower requirement (10[SUP]-13[/SUP] for HI-1) and is combined with a secondary baffling system to reach the 10[SUP]-15[/SUP] rejection performance in the second camera system (HI-2). This paper presents the last updates of the SECCHI/HI design concept, with the expected performance. A verification program is currently in progress. The on-going stray-light verification tests are discussed. A set of tests has been conducted in air, and under vacuum. The results are presented and compared with the expected theoretical data. [less ▲]

Detailed reference viewed: 16 (7 ULg)
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See detailDesign and Tests of Prestressed Concrete Beams
Franssen, Jean-Marc ULg; Brüls, Aloïs

in Hasemi (Ed.) Proc. 5th Int. Symp. on Fire Safety Science (1997)

Detailed reference viewed: 33 (3 ULg)
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See detailDesign and validation of a real-time spiking-neural-network decoder for brain–machine interfaces
Dethier, Julie ULg; Nuyujukian, Paul; Ryu, Stephen I et al

in Journal of Neural Engineering (2013), 10(3),

Objective. Cortically-controlled motor prostheses aim to restore functions lost to neurological disease and injury. Several proof of concept demonstrations have shown encouraging results, but barriers to ... [more ▼]

Objective. Cortically-controlled motor prostheses aim to restore functions lost to neurological disease and injury. Several proof of concept demonstrations have shown encouraging results, but barriers to clinical translation still remain. In particular, intracortical prostheses must satisfy stringent power dissipation constraints so as not to damage cortex. Approach. One possible solution is to use ultra-low power neuromorphic chips to decode neural signals for these intracortical implants. The first step is to explore in simulation the feasibility of translating decoding algorithms for brain–machine interface (BMI) applications into spiking neural networks (SNNs). Main results. Here we demonstrate the validity of the approach by implementing an existing Kalman-filter-based decoder in a simulated SNN using the Neural Engineering Framework (NEF), a general method for mapping control algorithms onto SNNs. To measure this system's robustness and generalization, we tested it online in closed-loop BMI experiments with two rhesus monkeys. Across both monkeys, a Kalman filter implemented using a 2000-neuron SNN has comparable performance to that of a Kalman filter implemented using standard floating point techniques. Significance. These results demonstrate the tractability of SNN implementations of statistical signal processing algorithms on different monkeys and for several tasks, suggesting that a SNN decoder, implemented on a neuromorphic chip, may be a feasible computational platform for low-power fully-implanted prostheses. The validation of this closed-loop decoder system and the demonstration of its robustness and generalization hold promise for SNN implementations on an ultra-low power neuromorphic chip using the NEF. [less ▲]

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See detailDesign and verification of the Far Ultraviolet Spectrographic Imager (FUV-SI) for the IMAGE mission
Renotte, Etienne ULg; Habraken, Serge ULg; Rochus, Pierre ULg et al

in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (1998, November 01)

The IMAGE FUV-SI is simultaneously imaging auroras at 121.8 nm and 135.8 nm. The spectrograph design challenge is the efficient rejection of the intense Lyman-alpha emission at 121.6 nm while passing its ... [more ▼]

The IMAGE FUV-SI is simultaneously imaging auroras at 121.8 nm and 135.8 nm. The spectrograph design challenge is the efficient rejection of the intense Lyman-alpha emission at 121.6 nm while passing its Doppler-shifted component at 121.8 nm. The FUV-SI opto-mechanical design, analysis integration, and verification of performances against environment are discussed in this paper. In absence of STM environmental constraints at subsystem levels are derived analytically from F.E.M. and used for pre-qualifying optical subsystems. [less ▲]

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See detailDesign as conceptual research and political instrument: role and legacy of the Italian Radical movement
Prina, Daniela ULg

in Glynne, Jonathan; Hackney, Fiona; Minton, Viv (Eds.) Proceedings of the 2008 Annual International Conference of the Design History Society (UK) University College Falmouth, 3-6 September (2010, June 01)

Detailed reference viewed: 15 (1 ULg)
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See detailIl design come strumento di lotta politica : il contributo del movimento Radical tra Firenze e Torino (1965-1975)
Prina, Daniela ULg

in Balicco, Daniele (Ed.) Made in Italy e cultura - Indagine sull'identità italiana contemporanea (2015)

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See detailIl design come strumento politico e ideologico, tra Firenze e Torino (1965-1975)
Prina, Daniela ULg

in Allegoria (2014), 68(2), 76-86

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See detailDesign criteria and experimental performance - Extended end-plate
Demonceau, Jean-François ULg

Conference (2016, June 21)

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See detailDesign criteria for a hybrid nano/photolithography system
Niblock, T.; Kraft, Michael ULg; Sehr, H.

in Proc. Conf. on Micromechanics Europe (2001)

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See detailDesign Decision Tool for Zero Energy Buildings, Passive and Low Energy Architecture,
Attia, Shady ULg; De Herde, André

in Proceedings of Passive and Low Energy Architecture (PLEA) 2011 (2011, July 13)

Proposing initial ideas for zero energy buildings is a difficult task. Various existing BPS tools have been proposed and are used to support the design of zero energy buildings during later design stages ... [more ▼]

Proposing initial ideas for zero energy buildings is a difficult task. Various existing BPS tools have been proposed and are used to support the design of zero energy buildings during later design stages. However, this is when many detailed decisions about the design have already been taken. There is a growing awareness to integrate BPS tools in the design process during early design phases. This is one of the main objectives of that we adopt here to develop a suggested decision tool. In this paper, we specifically discuss the realization of a tool for early architectural design of zero energy housing. The paper presents the first prototype of this tool that has been tested with different volunteers to see how they react. A major focus of his work is the graphical user interface. We describe the interface development process, the resulting prototype and its performance for initial design conception of different zero energy housing typologies. We also identify direction for future development of the tool. [less ▲]

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See detailLE DESIGN DES SYSTÈMES DE CONTRÔLE DE GESTION ADOPTÉS PAR LES SPIN-OFFS ACADÉMIQUES DE HAUTE TECHNOLOGIE : LE RÔLE DE L’INCERTITUDE PERÇUE
Van Caillie, Didier ULg; Kabwigiri, Charles ULg

Scientific conference (2007)

Uncertainty is one of the contingency factors examined by previous studies on management control systems design. However, its role remains unclear. This paper presents the results of an empirical study ... [more ▼]

Uncertainty is one of the contingency factors examined by previous studies on management control systems design. However, its role remains unclear. This paper presents the results of an empirical study, which shows that perceived uncertainty more intervenes to explain the of informal management control mechanisms and the interactive use of formal management control systems than to explain the nature of the latter. [less ▲]

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See detailLe design du système d’information comptable dans les PMI tunisiennes: une modélisation contingente
Ghorbel, Jihene ULg

Conference (2012, October 24)

Les petites et moyennes entreprises (PME) constituent l’un des piliers de l’économie tunisienne où elles représentent 97 % du tissu économique. Bien que les études consacrées aux PME tunisiennes (Adair et ... [more ▼]

Les petites et moyennes entreprises (PME) constituent l’un des piliers de l’économie tunisienne où elles représentent 97 % du tissu économique. Bien que les études consacrées aux PME tunisiennes (Adair et al., 2009 ; Fhima et al., 2009 ; Djelassi et al. , 2010 ) sont assez nombreuses, rares sont les recherches scientifiques qui portent sur les spécificités des PME industrielles. Or, comme les autres entreprises, les PMI tunisiennes sont forcées de s’adapter aux mutations profondes qui caractérisent nos environnements et cette adaptation passe par une évolution constante de leur système d’information, notamment dans sa dimension comptable. Notre contribution se propose dès lors d’étudier théoriquement, au départ de l'analyse de la littérature développée en contexte tunisien, les spécificités des PMI tunisiennes et d’examiner l’impact des facteurs de contingence tels que la taille, le cycle de vie, la structure organisationnelle, l’incertitude de l’environnement, le secteur d’activité, le profil du dirigeant, l’âge et l’exportation sur le design du système d’information comptable. [less ▲]

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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 ▲]

Detailed reference viewed: 153 (23 ULg)