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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, 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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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

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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 ▲]

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See detailDesign, synthesis and biological evaluation of cognitive enhancers acting through the potentiation of the AMPA receptors
Francotte, Pierre ULg

Doctoral thesis (2008)

Alzheimer’s disease (AD) represents one of the greatest health problems in industrialized countries considering the ageing population. Only four drugs are currently approved for the treatment of this ... [more ▼]

Alzheimer’s disease (AD) represents one of the greatest health problems in industrialized countries considering the ageing population. Only four drugs are currently approved for the treatment of this disease. As these drugs are characterized with a limited time efficacy, it has become urgent to develop additional innovative AD treatments. Amongst the approaches that are actively investigated, the one consisting in potentiating a subclass of glutamate receptors appears attractive. This well advanced pharmacological approach includes three major classes of compounds amongst which appear the benzothiadiazine 1,1-dioxides. The present thesis is a pursuit of the preliminary efforts that were published in 1998 and 2001 by our team. Based on promising in vitro results obtained with the lead compound 59, pharmacomodulations around 59’s structure have been achieved in order to enhance its in vivo activity and to optimize its pharmacokinetic parameters. First efforts were devoted to exploratory synthesis where attention was paid to the impact of the substituent introduced at the 7-position. Moreover, some pyridothiadiazine dioxides as well as thienothiadiazine dioxides were prepared. The most important part of our pharmacomodulations was focused on the thiadiazine ring system. Considering that the poor in vivo results obtained with 59 could be due to a metabolic weakness of the latter, the introduction of fluorine atoms was tempted as a lead optimization strategy. This approach was successful, since it led to the synthesis of 95b which was selected for further pharmacological evaluations. This new lead compound was shown to exert significant cognitive-enhancing effects in vivo after oral administration to Wistar rats. Moreover, the study of the metabolic degradation of 95b allowed the assessment of the starting hypothesis that had dictated the pharmacomodulation’s philosophy. Finally, additional exploratory pharmacomodulations were achieved notably leading to the preparation of a quinazolinone series and 1,4-benzothiazine compounds. This research allowed to significantly improve the pharmacokinetic profile of our series and led to the identification of 95b as a new lead compound. However, many pharmacomodulations remain to be explored. The data collected during this thesis are appealing further studies. Efforts in the near future should lead to the design of novel drug candidates among which a future innovative AD treatment could emerge. [less ▲]

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Peer Reviewed
See detailDesign, synthesis and biological evaluation of sulfonylureas as original non-prostanoïd thromboxane A2 receptor antagonists
Dogne, J. M.; De Leval, X.; Damas, J. et al

Conference (1998, November 27)

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Peer Reviewed
See detailDesign, synthesis and biological evaluation of sulfonylureas as original non-prostanoid thromboxane A2 receptor antagonists
Dogne, J. M.; De Leval, X.; Damas, J. et al

Poster (1998, November 27)

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Peer Reviewed
See detailDesign, synthesis and biological evaluation of sulfonylureas as original non-prostanoid thromboxane receptor antagonists
Dogne, J. M.; Varache-Lembege, M.; Damas, J. et al

Conference (1997, April)

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See detailDesign, synthesis and evaluation of graftable thrombin inhibitors for the preparation of blood-compatible polymer materials.
Salvagnini, Claudio; Michaux, Catherine; Remiche, Julie ULg et al

in Organic & Biomolecular Chemistry (2005), 3(23), 4209-20

Piperazinyl-amide derivatives of N-alpha-(3-trifluoromethyl-benzenesulfonyl)-L-arginine (1) were synthesized as graftable thrombin inhibitors. The possible disturbance of biological activity due to a ... [more ▼]

Piperazinyl-amide derivatives of N-alpha-(3-trifluoromethyl-benzenesulfonyl)-L-arginine (1) were synthesized as graftable thrombin inhibitors. The possible disturbance of biological activity due to a variable spacer-arm fixed on the N-4 piperazinyl position was evaluated in vitro, against human alpha-thrombin, and in blood coagulation assay. Molecular modelling (in silico analysis) and X-ray diffraction studies of thrombin-inhibitor complexes were also performed. The fixation of bioactive molecules on poly(butylene terephthalate) (PBT) and poly(ethylene terephthalate) (PET) membranes was performed by wet chemistry treatment and evaluated by XPS analysis. Surface grafting of inhibitor 1d improved the membrane hemocompatibility by reducing blood clot formation on the modified surface. [less ▲]

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