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See detailDesign and implementation of a MASH2-0 Electromechanical Sigma-Delta Modulator for capacitive MEMS sensors using dual quantization method
Almutairi, Bader; Alsheri, Ali; Kraft, Michael ULg

in Journal of Microelectromechanical Systems (2015)

In this paper, a new control structure based on the dual quantization technique is presented for an electromechanical sigma–delta modulator (EM-SD M) applied to a microelectromechanical system (MEMS ... [more ▼]

In this paper, a new control structure based on the dual quantization technique is presented for an electromechanical sigma–delta modulator (EM-SD M) applied to a microelectromechanical system (MEMS) accelerometer. The modulator adopts a 2-0 multistage noise shaping structure (MASH2-0), taking the advantage of the intrinsic linearity of single-bit quantization and the reduced quantization error of multibit quantization in a single modulator. The sensor system is studied by the system-level modeling and the hardware implementation based on the field-programmable gate array technology. The study shows that, MASH2-0 shares the benefits of a MASH2-2 architecture of having an inherent stability, a high overload input level, and a high dynamic range compared with single-loop EM-SD M. However, the MASH2-0 architecture benefits from a considerably simpler implementation, while achieving a higher dynamic range and a higher signal-to-noise ratio compared with a MASH2-2 and a fourth-order single-loop SDM architecture. A capacitive MEMS accelerometer was designed and employed with this control system. Within a bandwidth of 1 kHz, the sensor achieved a noise floor level of −130 dB and a bias instability as low as 20 μg at an integration time of 40 s. Simulation estimated a full scale of ±20 g acceleration. The investigation confirms the concept of the MASH2-0 structure and shows its potential as a closed-loop interface for high-performance capacitive MEMS accelerometers. [less ▲]

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See detailDesign and implementation of a T impedance matching network for the radiocommunication subsystem aboard the OUFTI-1 nanosatellite
Boutaayamou, Mohamed ULg; Crosset, Nicolas ULg; Werner, Xavier ULg et al

in Proceedings of the URSI Forum 2014 (2014, November 18)

We describe how we handled an unexpected impedance matching issue on the receiver side (at UHF) of the radiocommunication system aboard the OUFTI-1 nanosatellite of the University of Liège. Our approach ... [more ▼]

We describe how we handled an unexpected impedance matching issue on the receiver side (at UHF) of the radiocommunication system aboard the OUFTI-1 nanosatellite of the University of Liège. Our approach relied on a combination of novel analytical developments combined with experimentation. [less ▲]

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See detailDesign and implementation of a ‘physical activity day’ for overweight and obese youth
Cloes, Marc ULg; DEWANDRE, Anne-Cécile ULg; LEBRETHON, Marie-Christine ULg et al

in Tijdschrift van de Belgische Kinderarts = Journal du Pédiatre Belge (2015, March), 17(1),

This study aimed to analyze the development and implementation of an adapted physical activity day expected to underline to overweight/obese youth the role of PA and hw they could be more active in their ... [more ▼]

This study aimed to analyze the development and implementation of an adapted physical activity day expected to underline to overweight/obese youth the role of PA and hw they could be more active in their daily life. [less ▲]

Detailed reference viewed: 47 (8 ULg)
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See detailDesign and implementation of an advanced state estimation software
Van Cutsem, Thierry ULg; Mili, Lamine; Vandeloise, Philippe

in Proc. IFAC Symposium on Power Systems and Power Plant control (1986)

Detailed reference viewed: 23 (0 ULg)
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See detailDesign and implementation of an optimized double closed-loop control system for MEMS vibratory gyroscope
Chen, Fang; Yuan, Weizheng; Chang, Honglong et al

in IEEE Sensors Journal (2014), 14(1), 184--196

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See detailDesign and integrity assessment of high strength tubular structures for extreme loading conditions
Bursi, Oreste; Kumar, Anil; Demofonti, Giuseppe et al

Book published by European Commission (2012)

High Strength Steel (HSS) characterized by yield strength ranging between 500MPa to 700MPa has been available for many years. However, its use in onshore engineering is quite restrictive. Reasons were ... [more ▼]

High Strength Steel (HSS) characterized by yield strength ranging between 500MPa to 700MPa has been available for many years. However, its use in onshore engineering is quite restrictive. Reasons were threefold: i) Eurocodes covered steels with yield strength up to 460MPa; ii) higher costs than regular steel; iii) lack of conceptual design with HSS. Nonetheless very recently, there has been a growing trend for the use of HSS in tubular structures thanks to Eurocode 3 Part 1-12 (2006), that extended its scope to steel grades up to S690/S700MC. Along this line, the HITUBES project intended to develop performance-based designs and assessment procedures to make full use of HSS tubes up to S700MC for structures subject also to extreme repeated loads; in fact Eurocode 3 Part 1-12 imposes many limitations at the material, structural and design level. The ambitious targets are to increase the performance of tubular structures, reduce weights, construction and operating costs. The project covered the period 01/07/2008-31/12/2011, and main research work focussed on several aspects listed herein: literature survey; selection of finite element-based and identification dynamic analysis codes; selection of realistic Case Studies and FE analysis for the evaluation of actions and stresses; structural identification and health monitoring of a cable-stay and arch footbridges; tests planning and execution including welding procedure specifications; simulations of welded and bolted connections under monotonic, low-cycle and high-cycle fatigue loadings; simulation of Case studies and reliability analysis for quantification of realistic performance scenarios; SWOT analysis and monitoring of project activities. [less ▲]

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See detailDesign and methodology of the phase 3 trials for the clinical development of strontium ranelate in the treatment of women with postmenopausal osteoporosis
Meunier, P. J.; Reginster, Jean-Yves ULg

in Osteoporosis International (2003), 14(Suppl. 3), 66-76

The phase 3 program for strontium ranelate, a new oral agent in the treatment of women with postmenopausal osteoporosis, was aimed to assess the efficacy and safety of the daily oral dose of 2 g. This ... [more ▼]

The phase 3 program for strontium ranelate, a new oral agent in the treatment of women with postmenopausal osteoporosis, was aimed to assess the efficacy and safety of the daily oral dose of 2 g. This program was conducted in 12 countries, involved 75 centers, and was structured in 3 studies: FIRST (Fracture International Run-in for Strontium ranelate Trial), SOTI (Spinal Osteoporosis Therapeutic Intervention study) and TROPOS (TReatment Of Peripheral OSteoporosis). FIRST, a run-in open study, was designed to start the normalization of the calcium and vitamin D status of the patients, check all entry criteria, and ensure inclusion of a sufficient number of well-motivated patients in either one of the two therapeutic intervention protocols, SOTI or TROPOS: FIRST included 9,196 patients. SOTI and TROPOS were prospective, randomized, double-blind clinical trials comparing, in two parallel groups, the daily oral dose of 2 g of strontium ranelate with placebo, the patients of both groups receiving calcium and vitamin D according to their own deficiencies. The main objective of SOTI and TROPOS was to demonstrate a reduction in the incidence of postmenopausal women experiencing a new osteoporotic fracture (vertebral fracture in SOTI and nonvertebral fracture in TROPOS) over a 3-year treatment period, the total duration of the studies being 5 years. SOTI included 1,649 women with at least one osteoporotic vertebral fracture at inclusion and a lumbar BMD less than or equal to 0.840 g/cm(2). TROPOS included 5,091 women with a femoral neck BMD less than or equal to 0.600 g/cm(2). The phase 3 program for the clinical development of strontium ranelate in women with postmenopausal osteoporosis is a long-term program with the main statistical analysis after 3 years of treatment. Its aim is to demonstrate the effect of strontium ranelate on the axial and appendicular skeleton as well as its tolerability in osteoporotic patients with replete calcium and vitamin D stores. [less ▲]

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See detailDesign and modeling of new PAF antagonists - 1,4-bis-(3',4',5'-trimethoxybenzoyl)-2-substituted carbonyloxymethyl piperazines
Heymans, Françoise; Lamouri, Aazdine; Batt, Jean-Pierre et al

in Journal of Lipid Mediators and Cell Signalling (1994), 10(1-2), 153-154

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See detailDesign and modeling of new platelet-activating factor antagonists.2. Synthesis and biological activity of 1,4-bis-(3',4',5'-trimethoxybenzoyl)-2-alkyl and 2-alkoxymethylpiperazines
Tavet, Fabrice; Lamouri, Aazdine; Heymans, Françoise et al

in Journal of Lipid Mediators and Cell Signalling (1996), 15

Detailed reference viewed: 36 (1 ULg)
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See detailDesign and modeling of new platelet-activating factor antagonists.3. Relative importance of hydrophobicity and electronic distribution in piperazinic series
Heymans, Françoise; Dive, Georges ULg; Lamouri, Aazdine et al

in Journal of Lipid Mediators and Cell Signalling (1996), 15(2), 161-173

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See detailDesign and modeling of new platelet-activating-factor antagonists.1. Synthesis and biological activity of 1,4-bis(3',4',5'-trimethoxybenzoyl)-2-[[(substituted carbonyl and carbamoyl)oxy]methyl]piperazines
Lamouri, Aazdine; Heymans, Françoise; Tavet, Fabrice et al

in Journal of Medicinal Chemistry (1993), 36(8), 990-1000

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See detailDesign and modelisation of a straylight facility for space optical instrument
Mazy, Emmanuel ULg; Stockman, Yvan ULg; Hellin, Marie-Laure ULg

in SPIE (Ed.) 2012 Optical system Design (in press)

In the framework of instrument calibration, straylight issues are a critical aspect that can deteriorate the optical performances of instrument. To cope with this, a new facility is designed dedicated for ... [more ▼]

In the framework of instrument calibration, straylight issues are a critical aspect that can deteriorate the optical performances of instrument. To cope with this, a new facility is designed dedicated for in-field and far field straylight characterization: up to 10-8 for in-field and up to 10-10 for far field straylight in the visible to NIR spectral ranges. Moreover, from previous straylight test performed at CSL, vacuum conditions are needed for reaching the 10-10 rejection requirement mainly to avoid air/dust diffusion. The major constrains are to design a straylight facility either for in-field and out-field straylight measurements. That requires high dynamic range at source level and a high radiance point source allowing small diverging collimated beam. Moreover, the straylight facility has to be implemented into a limited envelope and has to be built with vacuum compatible materials and black coating. As checking the facility performance requires an instrument better than the facility itself, that is no easy to find, so that the performances have been estimated through a modelisation into a non sequential optical software. This modelisation is based on CAD importation of mechanical design, on BRDF characteristics of black coating and on statistical averaging of ray tracing at instrument entrance. [less ▲]

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See detailDesign and modelisation of ASPIICS optics
Galy, Camille ULg; Fineschi, S.; Galano, D. et al

in Proc. SPIE Volume 9604 Solar Physics and Space Weather Instrumentation VI (2015, September 21)

In the framework of development of ASPIICS (Association of Spacecraft for Polarimetric and Imaging Investigation of the Corona of the Sun), the Centre Spatial de Liege is responsible of the optical design ... [more ▼]

In the framework of development of ASPIICS (Association of Spacecraft for Polarimetric and Imaging Investigation of the Corona of the Sun), the Centre Spatial de Liege is responsible of the optical design of the coronagraph and the optics will be manufactured by TOPTEC. The particularity of this coronagraph is to have an external occulter located 150 m ahead of the first imaging lens. This external occulter is re-imaged on an internal occulter which function is - as in a classical externally occulted Lyot coronagraph - to block the sun light diffracted by the external occulter and to reduce the straylight on the detector. The selection of this configuration is driven by the requirement to observe the corona as close as possible to the solar limb (i.e. 1 RSun) without imaging the limb itself. A requirement of 1.08 RSun is specified at optical design level to grant 1.2 Rsun at instrument level. The coronograph instrument is designed to have a field of view of 1.6° x 1.6° with a resolution of less than 6 arcsec. Its performances are limited by diffraction in a 530 – 590 nm wavelength range. This paper presents the optical design and demonstrates that by design the requirements are fulfilled within the misalignment, manufacturing and thermo-elastic error contributions. [less ▲]

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See detailDESIGN AND MODELIZATION OF ACONVEX GRATING FOR AN HYPERSPECTRAL IMAGER OF THE CHANDRAYAAN 2 INSTRUMENT FOR THE MOON PROBE IN THE INFRARED
Sabushimike, Bernard ULg; Horugavye, Georges ULg; Piron, Pierre ULg et al

in International Journal of Latest Research in Science and Technology (2016), 5(2), 69-74

For hyperspectral imaging, diffraction gratings based spectrometers exhibit high spectral resolution and optical performance. Among those spectrometers, the Offner type (which consists of an entrance slit ... [more ▼]

For hyperspectral imaging, diffraction gratings based spectrometers exhibit high spectral resolution and optical performance. Among those spectrometers, the Offner type (which consists of an entrance slit, two concave mirrors and convex grating) offers a lot of advantages. In this paper, we propose the design and modelization of a convex grating which covers a spectral band ranging from 0.7 μm to 5 μm with a minimum diffraction efficiency of 20% at 800 nm, 50% at 3000 nm and 25% at 5000 nm. For a so wide band, a grating with a single blaze cannot satisfy these requirements. We will therefore propose an approach of multi-blaze grating which is subdivided into different sections each with its own blaze angle. Meanwhile, we perform the diffraction efficiency prediction using the scalar and rigorous theories to prove the compliance of this design with the technical specifications. The rigorous theory will also allow us to study the polarization sensitivity of this grating and the calculation of the diffraction efficiency of a grating with a profile degraded by manufacturing errors to assess the impact on the diffraction efficiency and the sensitivity to polarization [less ▲]

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See detailDesign and modelling of SOI-Based solar thermoelectric generators
de Leon, MT; Kraft, Michael ULg

in Proc. Eurosensors XXVI Conference (2013, September)

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

in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series (2005)

The Heliospheric Imager (HI) is part of the SECCHI suite of instruments on-board the two STEREO spacecrafts to be launched in 2006. Located on two different orbits, the two HI instruments will provide ... [more ▼]

The Heliospheric Imager (HI) is part of the SECCHI suite of instruments on-board the two STEREO spacecrafts to be launched in 2006. Located on two different orbits, the two HI instruments will provide stereographic images of solar coronal plasma and coronal mass ejections (CME) over a wide field of view (~90°), ranging from 13 to 330 solar radii (R[SUB]0[/SUB]). These observations complete the 15 R[SUB]0[/SUB] field of view of the solar corona obtained with the other SECCHI instruments (2 coronagraphs and an EUV imager). The HI instrument is a combination of 2 refractive optical systems with 2 different multi-vanes baffle system. 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]. The optics and baffles have been specifically designed to reach the required rejection. This paper presents the SECCHI/HI opto-mechanical design, with the achieved performances. A test program has been run on one flight unit, including vacuum straylight verification test, thermo-optical performance test and co-alignment test. The results are presented and compared with the initial specifications. [less ▲]

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See detailDesign and perspectives of the permanent GPS network in Belgium
Brondeel, Marijke; Bruyninx, Carine; Sleewaegen, Jean-Marie et al

in Reports On Geodesy (1997), 7(27), 199-209

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See detailDesign and pharmacological evaluation of recently developed 6-substituted 3-bromophenyl 2-oxo-2H-1-benzopyran 3-carboxylate derivatives as putative inhibitors of cell invasion
Kempen, I.; Frankenne, F.; Telliez, A. et al

in Fundamental & Clinical Pharmacology (2004)

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See detailDesign and production of bone scaffolds with selective laser melting
Van Bael, Simon; Vandenbroucke, Ben; Kerckhofs, Greet ULg et al

in TMS 2009 138TH ANNUAL MEETING & EXHIBITION - SUPPLEMENTAL PROCEEDINGS, VOL 1: MATERIALS PROCESSING AND PROPERTIES (2009)

The use of bone scaffolds for treatment of large bone defects could be a solution for many disadvantages which are present with traditional care methods. The success of these scaffolds depends on its ... [more ▼]

The use of bone scaffolds for treatment of large bone defects could be a solution for many disadvantages which are present with traditional care methods. The success of these scaffolds depends on its internal structure and mechanical properties. To be able to conduct a reliable investigation on the effect of these parameters, an efficient production method is required which can produce controlled internal structures. The presented work examines the ability to produce Ti6Al4V bone scaffolds with selective laser melting. The bone scaffolds were produced with a pore size range of 400-900 mu m and beam size 200 mu m. To check the repeatability mechanical and geometrical tests were performed. [less ▲]

Detailed reference viewed: 78 (4 ULg)