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See detailOnline Flight Flutter Testing
Dimitriadis, Grigorios ULg; Cooper, Jonathan E

in Link, M. (Ed.) Proceedings of the International Conference on Structural System Identification (2001, September)

A number of different identification methods are considered as candidate approaches to undertake online flight flutter testing. Rather than flying the test aircraft to a new flight condition and then ... [more ▼]

A number of different identification methods are considered as candidate approaches to undertake online flight flutter testing. Rather than flying the test aircraft to a new flight condition and then performing a data analysis at a constant flight condition, it is shown how it is feasible to track changes in frequencies and damping ratios as the flight speed is increased. It is also possible to provide an updated estimate of the predicted flutter speed, giving the flight engineers added confidence in the margin of safety. Both frequency and time domain methods are evaluated on a simulated 3 DOF aeroelastic system. These preliminary results show that such an approach is feasible although further work is required to determine the best testing and analysis approach. [less ▲]

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See detailOnline Grocery Shopping: The Challenge of Home Delivery Service
Hammedi, Wafa ULg; Van Riel, Allard ULg

Poster (2008, July 14)

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See detailAn online interactive tool for the energy assessment of residential buildings and transportation
Marique, Anne-Françoise ULg; de Meester, Tatiana; Reiter, Sigrid ULg

in Proceedings of PLEA 2012 (2012, November)

In the current context of increasing environmental awareness, energy efficiency is presented as a viable approach to the mitigation of climate change. In addition to public policies dealing with energy ... [more ▼]

In the current context of increasing environmental awareness, energy efficiency is presented as a viable approach to the mitigation of climate change. In addition to public policies dealing with energy efficiency, heightening public awareness on the impact of citizens’ lifestyles and behaviours is crucial and could quickly lead to significant reductions in the total energy consumption of a territory. This paper presents a new online interactive tool which enables citizens, local authorities and private developers (1) to assess energy consumption in the building and transportation sectors, at the individual and at the neighbourhood scales; (2) to compare them and (3) to find relevant and personalized hints to reduce their energy consumptions. Numerous methods and tools including a typological classification of buildings, thermal dynamic simulations, life-cycle assessments, statistical treatments of national censuses, etc. were used and combined to build the database used in the online interactive tool. This tool makes the main results of a scientific research accessible to a large non-specialized audience which is crucial in the scope of the sustainable development. Keywords: interactive tool, assessment methods, buildings, transportation, households, scientific popularization [less ▲]

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See detailAn online interactive tool to assess energy consumption in residential buildings and for daily mobility
Marique, Anne-Françoise ULg; de Meester, Tatiana; De Herde, André et al

in Energy and Buildings (in press)

Improving energy efficiency in the building and transportation sectors is a viable approach to mitigate the effects of climate change and has become an important policy target. As a result, in addition to ... [more ▼]

Improving energy efficiency in the building and transportation sectors is a viable approach to mitigate the effects of climate change and has become an important policy target. As a result, in addition to scientific research and public policies addressing energy efficiency, raising public awareness of the impact of the behaviour of citizens to energy efficiency is crucial and could quickly lead to significant reductions in the total energy consumption of a territory. In this context, this paper presents a new online interactive tool that enables not only citizens but also local authorities and private developers to (1) assess the sources of energy consumption related to housing and to daily mobility at both the individual and neighbourhood scales, (2) compare these sources and (3) determine relevant and personalised suggestions to reduce energy consumption. Numerous methods and tools, including a typological classification of buildings, thermal dynamic simulations, life-cycle assessments and statistical treatments of national censuses, were used to produce the two large databases used in this interactive tool. This report represents the primary results of a three-year long scientific research project dedicated to the study of energy efficiency in buildings and for daily mobility that is accessible to a large non-specialised audience. [less ▲]

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See detailOnline Learning of Gaussian Mixture Models - a Two-Level Approach
Declercq, Arnaud ULg; Piater, Justus ULg

in VISAPP 2008: Proceedings of the Third International Conference on Computer Vision Theory and Applications - Volume 1 (2008)

Online learning, Gaussian mixture model, Uncertain model. We present a method for incrementally learning mixture models that avoids the necessity to keep all data points around. It contains a single user ... [more ▼]

Online learning, Gaussian mixture model, Uncertain model. We present a method for incrementally learning mixture models that avoids the necessity to keep all data points around. It contains a single user-settable parameter that controls via a novel statistical criterion the trade-off between the number of mixture components and the accuracy of representing the data. A key idea is that each component of the (non-overfitting) mixture is in turn represented by an underlying mixture that represents the data very precisely (without regards to overfitting); this allows the model to be refined without sacrificing accuracy. [less ▲]

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See detailOnline least-squares policy iteration for reinforcement learning control
Busoniu, Lucian; Ernst, Damien ULg; De Schutter, Bart et al

in Proceedings of the 2010 American Control Conference (2010)

Reinforcement learning is a promising paradigm for learning optimal control. We consider policy iteration (PI) algorithms for reinforcement learning, which iteratively evaluate and improve control ... [more ▼]

Reinforcement learning is a promising paradigm for learning optimal control. We consider policy iteration (PI) algorithms for reinforcement learning, which iteratively evaluate and improve control policies. State-of-the-art, least-squares techniques for policy evaluation are sample-efficient and have relaxed convergence requirements. However, they are typically used in offline PI, whereas a central goal of reinforcement learning is to develop online algorithms. Therefore, we propose an online PI algorithm that evaluates policies with the so-called least-squares temporal difference for Q-functions (LSTD-Q). The crucial difference between this online least-squares policy iteration (LSPI) algorithm and its offline counterpart is that, in the online case, policy improvements must be performed once every few state transitions, using only an incomplete evaluation of the current policy. In an extensive experimental evaluation, online LSPI is found to work well for a wide range of its parameters, and to learn successfully in a real-time example. Online LSPI also compares favorably with offline LSPI and with a different flavor of online PI, which instead of LSTD-Q employs another least-squares method for policy evaluation. [less ▲]

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See detailOnline monitoring of heterogeneous polymerizations in supercritical carbon dioxide by Raman spectroscopy
Grignard, Bruno ULg; Gilbert, Bernard ULg; Malherbe, Cédric ULg et al

in Chemphyschem : A European Journal of Chemical Physics and Physical Chemistry (2012), 13(11), 2666-2670

A novel setup is described to monitor the kinetics of homogeneous and heterogeneous reactions online using Raman spectroscopy under high pressure. The arrangement is based on a high-pressure reactor ... [more ▼]

A novel setup is described to monitor the kinetics of homogeneous and heterogeneous reactions online using Raman spectroscopy under high pressure. The arrangement is based on a high-pressure reactor equipped with a sapphire window in combination with a mobile probe that allows the collection of the back-scattered Raman signal at 360°. [less ▲]

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See detailOnline monitoring of the interaction of balls and slurry with the Sensomag ®
Köttgen, Axel; Leroy, Sophie ULg; Bastin, David ULg et al

Poster (2012, December 10)

Presentation of Optimag Project results. Optimag aims to optimize the ball milling operations through the use of an embarked sensor, called the Sensomag, and developed by Magotteaux to monitor in real ... [more ▼]

Presentation of Optimag Project results. Optimag aims to optimize the ball milling operations through the use of an embarked sensor, called the Sensomag, and developed by Magotteaux to monitor in real time the position of the slurry and the grinding balls. [less ▲]

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See detailOnline Sparse Bandit for Card Games
Lupien St-Pierre, David ULg; Louveaux, Quentin ULg; Teytaud, Olivier

in Advance in Computer Games (2011)

Finding an approximation of a Nash equilibria in matrix games is an important topic that reaches beyond the strict application to matrix games. A bandit algorithm commonly used to approximate a Nash ... [more ▼]

Finding an approximation of a Nash equilibria in matrix games is an important topic that reaches beyond the strict application to matrix games. A bandit algorithm commonly used to approximate a Nash equilibrium is EXP3. However, the solution to many problems is often sparse, yet EXP3 inherently fails to exploit this property. To the knowledge of the authors, there exist only an offline truncation to tackle such issue. In this paper, we propose a variation of EXP3 to exploit the fact that solution is sparse by dynamically removing arms; the resulting algorithm empirically performs better than previous versions. We apply the resulting algorithm to a MCTS program for the Urban Rivals card game. [less ▲]

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See detailOnline travel service quality: The role of pre-transaction services
Van Riel, Allard ULg; Semeijn, Janjaap; Pauwels, Pieter

in Total Quality Management & Business Excellence (2004), 15(4), 475-493

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See detailOnline Voltage Security Assessment in the Hellenic Interconnected System
Vournas, Costas; Christoforidis, George; Van Cutsem, Thierry ULg

in Savulescu, Savu (Ed.) Real-Time Stability Assessment in Modern Power System Control Centers (2009)

Detailed reference viewed: 61 (1 ULg)
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See detailOnly Connect: An Interview with Caryl Phillips on Foreigners
Ledent, Bénédicte ULg; Phillips, Caryl

in Schatteman, Renée T. (Ed.) Conversations with Caryl Phillips (2009)

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See detailOnomastique grecque et histoire romaine: quelques réflexions à propos d'une concordance d'Appien
Famerie, Etienne ULg

in Revue. Informatique et statistiques appliquées aux sciences humaines (1990), 26

Survey of different problems of lemmatization with Roman proper names (of persons, of places) transposed in Greek by Appian

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See detailThe onset of NPQ and Deltamu(H)+ upon illumination of tobacco plants studied through the influence of mitochondrial electron transport.
Cardol, Pierre ULg; De Paepe, Rosine; Franck, Fabrice ULg et al

in Biochimica et Biophysica Acta (2010), 1797(2), 177-88

The relationship between the development of photoprotective mechanisms (non-photochemical quenching, NPQ), the generation of the electrochemical proton gradient in the chloroplast and the capacity to ... [more ▼]

The relationship between the development of photoprotective mechanisms (non-photochemical quenching, NPQ), the generation of the electrochemical proton gradient in the chloroplast and the capacity to assimilate CO(2) was studied in tobacco dark-adapted leaves at the onset of illumination with low light. These conditions induce the generation of a transient NPQ, which relaxes in the light in parallel with the activation of the Calvin cycle. Wild-type plants were compared with a CMSII mitochondrial mutant, which lacks the respiratory complex I and shows a delayed activation of photosynthesis. In the mutant, a slower onset of photosynthesis was mirrored by a decreased capacity to develop NPQ. This correlates with a reduced efficiency to reroute electrons at the PSI reducing side towards cyclic electron flow around PSI and/or other alternative acceptor pools, and with a smaller ability to generate a proton motive force in the light. Altogether, these data illustrate the tight relationship existing between the capacity to evacuate excess electrons accumulated in the intersystem carriers and the capacity to dissipate excess photons during a dark to light transition. These data also underline the essential role of respiration in modulating the photoprotective response in dark-adapted leaves, by poising the cellular redox state. [less ▲]

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See detailThe onset of photometric variability in red giant stars.
Jorissen, A.; Mowlavi, N.; Sterken, C. et al

in Astronomy and Astrophysics (1997), 324

The onset of variability in red giant stars is studied from the data collected by the `Long-Term Photometry of Variables' project which operates at ESO (La Silla) since 1982. The differential nature of ... [more ▼]

The onset of variability in red giant stars is studied from the data collected by the `Long-Term Photometry of Variables' project which operates at ESO (La Silla) since 1982. The differential nature of the observations combined with a multi-night reduction algorithm enables to study the variability of over 50 red giants with an accuracy of the order of 2 to 3 millimagnitudes on time scales ranging from days to years. All red giants with spectral types late G to early K (i.e. b-y~0.6-0.8) are stable at the level Ï _y_<6millimag (where Ï _y_ is the standard deviation of the Stroemgren y magnitude). Red giants with later spectral types are all variable, and it is found that the minimum variability level Ï _y, min_ increases with increasing b-y, thus defining a minimum-variability boundary. The new data obtained in this paper reveal that the time scale of the associated variability increases with increasing b-y (and thus amplitude), and that the stability of this time scale improves concomitantly. More precisely, irregular variations on time scales of 5 to 10-days (and Ï _y_~7millimag) characterize red giants with b-y~1.0, whereas the variations (with Ï _y_~100millimag) become more regular with periods of the order of 50d for red giants with b-y~1.3. A radial-velocity jitter (of the order of 1.5km/s r.m.s.) is associated with this photometric variability, and suggests that stellar oscillations may be responsible for the observed variations. [less ▲]

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See detailOnset of thermal ripples at the interface of an evaporating liquid under a flow of inert gas
Scheid, B.; Margerit, J.; Iorio, C. S. et al

in Experiments in Fluids (2012), 52

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See detailOnset Time of Neuromuscular Block and Intubating Conditions: Influence of Different Stimulation Patterns
Hans, Pol ULg; Dewé, Walthère ULg; Albert, Adelin ULg

in Acta Anaesthesiologica Belgica (1997), 48(1), 15-21

Detailed reference viewed: 2 (0 ULg)