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See detailDesign, implementation, and test of a digitally-controlled electrical power supply for the OUFTI-1 nanosatellite
Kolodziej, Marie; Ledent, Philippe; Thirion, Pierre et al

Poster (2010)

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See detailDesign, implementation, and tests of the architecture of the radiocommunication system of the OUFTI-1 CubeSat
Marchal, Nicolas; Broun, Valéry; Denis, Amandine ULg et al

Poster (2010)

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See detailDesign, manufacturing, and performance analysis of mid-infrared achromatic half-wave plates with diamond subwavelength gratings
Delacroix, Christian ULg; Forsberg, Pontus; Karlsson, Mikael et al

in Applied Optics (2012), 51

In this paper, we present an elegant solution for creating robust monolithic achromatic half-wave plates (HWPs) for the infrared, based on the form birefringence of subwavelength gratings (SWGs) made out ... [more ▼]

In this paper, we present an elegant solution for creating robust monolithic achromatic half-wave plates (HWPs) for the infrared, based on the form birefringence of subwavelength gratings (SWGs) made out of diamond. We use the rigorous coupled wave analysis to design the gratings. Our analysis shows that diamond, besides its outstanding physical and mechanical properties, is a suitable substrate to manufacture mid-infrared HWPs, thanks to its high refractive index which allows etching SWGs with lower aspect ratio. Based on our optized design, we manufactured a diamond HWP for the 11-13.2 µm region, with an estimated mean retardance ~3.143 ± 0.061 rad (180.08 ± 3.51°). In addition, an antireflective grating was etched on the backside of the wave plate, allowing a total tansmittance between 89 and 95% over the band. [less ▲]

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See detailDESIGN, MODELING AND EXPERIMENTATION OF A REVERSIBLE HP-ORC PROTOTYPE
Dumont, Olivier ULg; Quoilin, Sylvain ULg; Lemort, Vincent ULg

Conference (2014)

This paper presents an innovative system comprising a heat pump connected to a solar roof and a geothermal heat exchanger. This heat pump is also able to invert its cycle and operate as an ORC. By using ... [more ▼]

This paper presents an innovative system comprising a heat pump connected to a solar roof and a geothermal heat exchanger. This heat pump is also able to invert its cycle and operate as an ORC. By using the whole rooftop (hereunder called “absorber”) as a heat source, a large amount of heat is generated throughout the year. This heat is used in priority to cover the building annual heating needs and the surplus heat generated during the summer is utilized to generate electricity in a so-called HP/ORC module. This paper will thus focus on these two main points: designing of the prototype and results from experimentation. This paper demonstrates the feasibility of such a prototype with encouraging performance in ORC and HP modes. Experimentally, a COP of 4.2 is reached in heat pump mode and a global efficiency of 5.6 is obtained in ORC mode. Possible means of improvement and perspectives are finally described. [less ▲]

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See detailDesign, Modeling and Performance Optimisation of a Reversible HP-ORC Prototype
Quoilin, Sylvain ULg; Dumont, Olivier ULg; Lemort, Vincent ULg

Conference (2013, October 08)

Building is one of the economical sectors where solutions are available to significantly reduce energy consumption and greenhouse gases emissions. Among other, heat pumps offer promising perspectives to ... [more ▼]

Building is one of the economical sectors where solutions are available to significantly reduce energy consumption and greenhouse gases emissions. Among other, heat pumps offer promising perspectives to provide energy-efficient space and sanitary hot water heating in many applications. This paper presents an innovative system comprising a heat pump connected to a solar roof and a geothermal heat exchanger. This heat pump is also able to invert its cycle and operate as an ORC. By using the whole rooftop (hereunder called “absorber”) as a heat source, a large amount of heat is generated throughout the year. This heat is used in priority to cover the building annual heating needs and the surplus heat generated during the summer is utilized to generate electricity in the so-called HP/ORC module. The same module can be used during winter as an efficient heat pump which radically reduces the complexity of the total system. The main advantage of the proposed technology is due to the reversibility of scroll machines, which have proven to operate efficiently both as compressor and as an expander in lab testing. [less ▲]

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See detailDesign, Modeling, and Performance Optimization of a Reversible Heat Pump/Organic Rankine Cycle System for Domestic Application
Quoilin, Sylvain ULg; Dumont, Olivier ULg; Harley Hansen, Kristian et al

in Journal of Engineering for Gas Turbines and Power (2015)

In this paper, an innovative system combining a heat pump (HP) and an organic Rankine cycle (ORC) process is proposed. This system is integrated with a solar roof, which is used as a thermal source to ... [more ▼]

In this paper, an innovative system combining a heat pump (HP) and an organic Rankine cycle (ORC) process is proposed. This system is integrated with a solar roof, which is used as a thermal source to provide heat in winter months (HP mode) and electricity in summer months (ORC mode) when an excess irradiation is available on the solar roof. The main advantage of the proposed unit is its similarity with a traditional HP: the HP/ORC unit only requires the addition of a pump and four-way valves compared to a simple HP, which can be achieved at a low cost. A methodology for the optimal sizing and design of the system is proposed, based on the optimization of both continuous parameters such as heat exchanger size or discrete variables such as working fluid. The methodology is based on yearly simulations, aimed at optimizing the system performance (the net yearly power generation) over its whole operating range instead of just nominal sizing operating conditions. The simulations allow evaluating the amount of thermal energy and electricity generated throughout the year, yielding a net electric power output of 3496 kWh throughout the year. [less ▲]

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See detailDesign, modeling, fabrication, and evaluation of thermoelectric generators with hot-wire chemical vapor deposited polysilicon as thermoelement material
De Leon, M. T.; Tarazona, Antulio; Chong, Harold et al

in Journal of Electronic Materials (2014), 43(11), 4070-4081

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See detailDesign, modelling and simulation of a PZN-PT actuated micropump
Malleo, D; Haas, C; Kraft, Michael ULg

in Design, modelling and simulation of a PZN-PT actuated micropump (2005)

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See detailDesign, modelling, performance optimization and experimentation of a reversible HP/ORC prototype.
Dumont, Olivier ULg; Quoilin, Sylvain ULg; Lemort, Vincent ULg

Conference (2014)

This paper presents an innovative system comprising a water/water heat pump connected to a solar roof and a geothermal heat exchanger. This unit is able to invert its cycle and operate as an Organic ... [more ▼]

This paper presents an innovative system comprising a water/water heat pump connected to a solar roof and a geothermal heat exchanger. This unit is able to invert its cycle and operate as an Organic Rankine Cycle. The solar roof is producing a large amount of heat throughout the year. This allows covering the building annual heating needs and furthermore, electricity is produced thanks to the surplus of heat in a so-called HP/ORC reversible unit. This paper is focusing on these three main points: modeling, design and experimentation of the prototype. This paper demonstrates the feasibility of such a prototype with encouraging performance in ORC and HP modes. First simulations of the HP/ORC system, with components optimally sized, indicate that, in ORC mode, for the weather conditions of Copenhagen, the electrical energy produced over one year reaches 4030 kWh and the nominal efficiency of the cycle is 7.6%. The nominal COP of the heat pump is 4.2 (condenser exhaust temperature of 60°C and evaporator supply temperature of 15°C). Experimentally, a COP of 4.21 (condensation temperature of 61°C and evaporation temperature of 21°C). is achieved in heat pump mode and a global ORC efficiency of 5.7% is obtained in ORC mode (condenser exhaust temperature of 25°C and evaporator supply temperature of 88°C). [less ▲]

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See detailDesign, performance analysis, and implementation of a positioning system for autonomous mobile robots
Pierlot, Vincent ULg

Doctoral thesis (2013)

Positioning is a fundamental issue in mobile robot applications, and it can be achieved in multiple ways. Among these methods, triangulation based on angle measurements is widely used, robust, and ... [more ▼]

Positioning is a fundamental issue in mobile robot applications, and it can be achieved in multiple ways. Among these methods, triangulation based on angle measurements is widely used, robust, and flexible. In this thesis, we present an original beacon-based angle measurement system, an original triangulation algorithm, and a calibration method, which are parts of an absolute robot positioning system in the 2D plane. Also, we develop a theoretical model, useful for evaluating the performance of our system. In the first part, we present the hardware system, named BeAMS, which introduces several innovations. A simple infrared receiver is the main sensor for the angle measurements, and the beacons are common infrared LEDs emitting an On-Off Keying signal containing the beacon ID. Furthermore, the system does not require an additional synchronization channel between the beacons and the robot. BeAMS introduces a new mechanism to measure angles: it detects a beacon when it enters and leaves an angular window. This allows the sensor to analyze the temporal evolution of the received signal inside the angular window. In our case, this feature is used to code the beacon ID. Then, a theoretical framework for a thorough performance analysis of BeAMS is provided. We establish the upper bound of the variance and its exact evolution as a function of the angular window. Finally, we validate our theory by means of simulated and experimental results. The second part of the thesis is concerned with triangulation algorithms. Most triangulation algorithms proposed so far have major limitations. For example, some of them need a particular beacon ordering, have blind spots, or only work within the triangle defined by the three beacons. More reliable methods exist, but they have an increasing complexity or they require to handle certain spatial arrangements separately. Therefore, we have designed our own triangulation algorithm, named ToTal, that natively works in the whole plane, and for any beacon ordering. We also provide a comprehensive comparison between other algorithms, and benchmarks show that our algorithm is faster and simpler than similar algorithms. In addition to its inherent efficiency, our algorithm provides a useful and unique reliability measure, assessable anywhere in the plane, which can be used to identify pathological cases, or as a validation gate in data fusion algorithms. Finally, in the last part, we concentrate on the biases that affect the angle measurements. We show that there are four sources of errors (or biases) resulting in inaccuracies in the computed positions. Then, we establish a model of these errors, and we propose a complete calibration procedure in order to reduce the final bias. Based on the results obtained with our calibration setup, the angular RMS error of BeAMS has been evaluated to 0.4 deg without calibration, and to 0.27 deg, after the calibration procedure. Even for the uncalibrated hardware, BeAMS has a better performance than other prototypes found in the literature and, when the system is calibrated, BeAMS is close to state of the art commercial systems. [less ▲]

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Peer Reviewed
See detailDesign, synthèse et évaluation biologique de nouveaux dérivés coumariniques inhibiteurs de protéases à sérine
Schynts, M.; Jiang, K. Y.; Thierry, N. et al

Poster (1994, January 19)

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Peer Reviewed
See detailDesign, synthèse et évaluation pharmacologique de nouvelles 2-alkylamino-quinazoline-4-ones en tant du’isostères de 3-alkylamino-4H-pyrido[4,3-e]-1,2,4-thiadiazine 1,1-dioxydes
Somers, F.; Rogister, F.; Ouedraogo, R. et al

in Journal de Pharmacie de Belgique (1998), 53

Detailed reference viewed: 9 (0 ULg)
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See detailDesign, synthesis and anticancer activity of novel hydroxylated coumarin derivatives
Hemmer, Marc ULg; De Tullio, Pascal ULg; Bernard, Y. et al

Conference (2007, October)

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See detailDesign, Synthesis and Biological Activity of a Series of Torasemide Derivatives, Potent Blockers of the Na+ 2cl- K+ Co-Transporter: In-Vitro Study
Masereel, B.; Lohrmann, E.; Schynts, M. et al

in Journal of Pharmacy & Pharmacology (1992), 44

Pharmacomodulation of the torasemide molecule, a loop diuretic inhibiting Na+ 2Cl- K+ co-transport in the thick ascending limb of the loop of Henle has been performed in order to obtain new long-acting ... [more ▼]

Pharmacomodulation of the torasemide molecule, a loop diuretic inhibiting Na+ 2Cl- K+ co-transport in the thick ascending limb of the loop of Henle has been performed in order to obtain new long-acting diuretics. The aim of this study was to decrease the metabolism of the drug and to slow down its rate of excretion by increasing its hydrophobicity. The present study describes the synthesis and the inhibitory potency of new torasemide derivatives in the bioassay system of the cortical thick ascending limb of rabbit. A correlation between the lipophilicity (log P') of these substances and their activity as inhibitors of the Na+ Cl- K+ co-transporter was observed. The present design led to compounds more active than torasemide. Structure-activity relationships permit us to propose an interaction model between torasemide derivatives and the Na+ 2Cl- K+ co-transport system of the cortical thick ascending limb. [less ▲]

Detailed reference viewed: 10 (0 ULg)