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See detailExperiments on a pitch-plunge wing undergoing limit cycle oscillation
Norizham, Abdul Razak ULg; Rothkegel Ide, José Ignacio ULg; Dimitriadis, Grigorios ULg

in Proceedings of the 53rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference (2012, April 25)

The aeroelastic behaviour of a wing oscillating in the heave and pitch degrees of freedom is examined by means of wind tunnel experiment. The phenomena of interest are classical flutter and limit cycle ... [more ▼]

The aeroelastic behaviour of a wing oscillating in the heave and pitch degrees of freedom is examined by means of wind tunnel experiment. The phenomena of interest are classical flutter and limit cycle oscillation. Classical flutter is normally associated with the exponential growth of the response amplitude. Linear flutter theory only predicts the critical flutter speed. Any excitation or disturbance beyond the critical speed is assumed to cause exponential growth in the response amplitude. In contrast, any limited amplitude oscillations occurring post-fultter suggest the existence of nonlinear properties in the system. Such properties can originate from the aerodynamic forces in the form of flow separation and reattachment. On the structural side, damping and stiffness can also contribute nonlinear properties. Furthermore, these nonlinearities can manifest themselves even at pre-flutter conditions, depending on the values of some governing parameter. The focus of the present work is the transformation of classical flutter into stall flutter as the equilibrium angle of attack of heaving and pitching wing is increased. The interaction of stall-related nonlinearity with structural nonlinearities is also of interest. The measured aeroelastic responses are analyzed and the bifurcation behavior of the dynamic system is characterized. Structural responses as well as flow field visualization through Particle Image Velocimetry show the origin of nonlinearity does not solely come from the manifestation of separation and the shedding of vortices, but from the structural nonlinearity which limits the response amplitude. [less ▲]

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See detailExperiments on liquid immiscibility along tholeiitic liquid lines of descent
Charlier, Bernard ULg; Grove, T. L.

in Contributions to Mineralogy and Petrology (2012), 164(1), 27-44

Crystallization experiments have been conducted on compositions along tholeiitic liquid lines of descent to define the compositional space for the development of silicate liquid immiscibility. Starting ... [more ▼]

Crystallization experiments have been conducted on compositions along tholeiitic liquid lines of descent to define the compositional space for the development of silicate liquid immiscibility. Starting materials have 46-56 wt% SiO 2, 11.7-17.7 wt% FeO tot, and Mg-number between 0.29 and 0.36. These melts fall on the basaltic trends relevant for Mull, Iceland, Snake River Plain lavas and for the Sept Iles layered intrusion, where large-scale liquid immiscibility has been recognized. At one atmosphere under anhydrous conditions, immiscibility develops below 1,000-1,020°C in all of these compositionally diverse lavas. Extreme iron enrichment is not necessary; immiscibility also develops during iron depletion and silica enrichment. Variations in melt composition control the development of silicate liquid immiscibility along the tholeiitic trend. Elevation of Na 2O + K 2O + P 2O 5 + TiO 2 promotes the development of two immiscible liquids. Increasing melt CaO and Al 2O 3 stabilizes a single-liquid field. New data and published phase equilibria show that anhydrous, low-pressure fractional crystallization is the most favorable condition for unmixing during differentiation. Pressure inhibits immiscibility because it expands the stability field of high-Ca clinopyroxene, which reduces the proportion of plagioclase in the crystallizing assemblage, thus enhancing early iron depletion. Magma mixing between primitive basalt and Fe-Ti-P-rich ferrobasalts can serve to elevate phosphorous and alkali contents and thereby promote unmixing. Water might decrease the temperature and size of the two-liquid field, potentially shifting the binodal (solvus) below the liquidus, leading the system to evolve as a single-melt phase. © 2012 Springer-Verlag. [less ▲]

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See detailExperiments on the role of gas height in the Rayleigh-Marangoni instability problem.
Ozen, O.; Theisen, E.; Johnson, Duane T et al

in Journal of Colloid & Interface Science (2005), 289(1), 271-5

Experimental evidence is provided to show the effect of gas phase dynamics on the onset of thermal convection and on the accompanying patterns in a silicone oil-air convecting bilayer. Very good agreement ... [more ▼]

Experimental evidence is provided to show the effect of gas phase dynamics on the onset of thermal convection and on the accompanying patterns in a silicone oil-air convecting bilayer. Very good agreement with three-dimensional calculations for linearized stability is obtained mostly for small and large gas heights. Reasons for this agreement as well as the results at intermediate gas heights are qualitatively explained from the perspective of well-established nonlinear analysis. [less ▲]

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See detailExperiments with the interior-point method for solving large scale Optimal Power Flow problems
Capitanescu, Florin; Wehenkel, Louis ULg

in Electric Power Systems Research (2013), 95

This paper reports extensive results obtained with the interior-point method (IPM) for nonlinear programmes (NLPs) stemming from large-scale and severely constrained classical Optimal Power Flow (OPF) and ... [more ▼]

This paper reports extensive results obtained with the interior-point method (IPM) for nonlinear programmes (NLPs) stemming from large-scale and severely constrained classical Optimal Power Flow (OPF) and Security-Constrained Optimal Power Flow (SCOPF) problems. The paper discusses transparently the problems encountered such as convergence reliability and speed issues of the method. [less ▲]

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See detailExpert consensus for multi-modality imaging evaluation of cardiovascular complications of radiotherapy in adults: a report from the European Association of Cardiovascular Imaging and the American Society of Echocardiography.
LANCELLOTTI, Patrizio ULg; Nkomo, Vuyisile T.; Badano, Luigi P. et al

in European Heart Journal - Cardiovascular Imaging (2013), 14(8), 721-40

Cardiac toxicity is one of the most concerning side effects of anti-cancer therapy. The gain in life expectancy obtained with anti-cancer therapy can be compromised by increased morbidity and mortality ... [more ▼]

Cardiac toxicity is one of the most concerning side effects of anti-cancer therapy. The gain in life expectancy obtained with anti-cancer therapy can be compromised by increased morbidity and mortality associated with its cardiac complications. While radiosensitivity of the heart was initially recognized only in the early 1970s, the heart is regarded in the current era as one of the most critical dose-limiting organs in radiotherapy. Several clinical studies have identified adverse clinical consequences of radiation-induced heart disease (RIHD) on the outcome of long-term cancer survivors. A comprehensive review of potential cardiac complications related to radiotherapy is warranted. An evidence-based review of several imaging approaches used to detect, evaluate, and monitor RIHD is discussed. Recommendations for the early identification and monitoring of cardiovascular complications of radiotherapy by cardiac imaging are also proposed. [less ▲]

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See detailExpert consensus for multimodality imaging evaluation of adult patients during and after cancer therapy: a report from the American Society of Echocardiography and the European Association of Cardiovascular Imaging.
Plana, Juan Carlos; Galderisi, Maurizio; Barac, Ana et al

in European heart journal cardiovascular Imaging (2014), 15(10), 1063-93

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See detailExpert Evidence before the EC Courts
Barbier de La Serre, Eric; Sibony, Anne-Lise ULg

in Common Market Law Review (2008), 45(4), 941985

The EC courts are regularly asked to rule on complex scientific and technical matters, as illustrated by cases concerning the foot and mouth crisis or conglomerate effects in merger control. In order to ... [more ▼]

The EC courts are regularly asked to rule on complex scientific and technical matters, as illustrated by cases concerning the foot and mouth crisis or conglomerate effects in merger control. In order to apprehend these technical issues, the EC courts may, like any other court, rely on experts who are appointed either by the courts themselves or by the parties. However, the law on the use of expert evidence by the EC courts is unclear on many aspects. The purpose of this article is therefore to set out briefly the law on expert evidence, to explore how the EC courts use it and to assess whether improvements are desirable. Section 2 of this article describes how the EC courts use “neutral” expert evidence (i.e., evidence obtained through an expert’s report commissioned by the court). An analysis of the case law reveals a paradox: while the status of neutral expert evidence is clearly defined by the rules of procedure governing the EC courts, such evidence is rarely used in practice. Section 2 therefore also endeavours to explain why the use of neutral expert evidence remains exceptional. Section 3 focuses on how the EC courts use “partisan” expert evidence (i.e., expert evidence that is voluntarily submitted by the parties). It shows that partisan expert evidence is the mirror image of neutral expert evidence: while its procedural status is unclear, it is widely used before the EC courts. Finally, in Section 4, it is argued that this situation is not wholly satisfactory. It is submitted inter alia that there is no convincing justification for systematic self-restraint over technical issues. Some changes are therefore explored which could be contemplated in order to improve the use of expert evidence by the EC courts. [less ▲]

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See detailExpert Judgement in a risk assessment model for Salmonella spp. in pork : on the performance of different weighting schemes.
Boone, Ides; Van der Stede, Yves; Bollaerts, Kaatje et al

in Preventive Veterinary Medicine (2009), 92

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See detailExpert system : a versatile tool for the real time control of a solar building
Nicolas, Jacques ULg; Andre, Philippe ULg

in Journal on automatic control (1992), 33(3), 99-105

The expert-system approach is well suited to manage complexes heating systems, with various energy sources and different possible strategies of heating or cooling. A specific computer tool is applied on ... [more ▼]

The expert-system approach is well suited to manage complexes heating systems, with various energy sources and different possible strategies of heating or cooling. A specific computer tool is applied on the solar-assisted heat pump system of Fondation Universitaire Luxembourgeoise in Arlon. It is developed around a list of rules of the type : "if…then.." and the code is written in Prolog language. The main difficulty of implementing such tool is the managing of time, because every sensor or actuator reacts in real time and a decision has first to be tested and validated before issuing on-line action on the system. The main advantage of the approach is that expert-system can very easily encapsulate the experimental knowledge of the heating system manager, simply by adding some rules in the rule base. [less ▲]

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See detailAn Expert System for the Identification of Nonlinear Dynamical Systems
Dimitriadis, Grigorios ULg; Vio, Gareth Arthur; Shi, Dongfeng

in Huang, De-Shuang; Li, Kang; Irwin, George William (Eds.) Intelligent Computing (2006, August)

This paper describes an Expert System that can detect and quantify the nonlinearity present in a given dynamical system and, subsequently, determine and apply the most suitable nonlinear system ... [more ▼]

This paper describes an Expert System that can detect and quantify the nonlinearity present in a given dynamical system and, subsequently, determine and apply the most suitable nonlinear system identification method. The internal workings, algorithms and decision making processes of the Expert System are discussed. For demonstration purposes the Expert System is applied to a nonlinear experimental test-rig. The results show that the Expert System is an automatic tool that will detect nonlinearity, choose the best class of model for the system under investigation and perform optimal parameter estimation, so that the resulting identified models are parsimonious and accurate. [less ▲]

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See detailAn expert system for the real time control of a building heating plant
Nicolas, Jacques ULg; Andre, Philippe ULg; Rivez, Jean-François et al

in Proceedings of the Third international conference on system simulation in buildings (1990, December)

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See detailExpertise des manuels Tweetalig Graag (1 et 2) et Spoed
Simons, Germain ULg

Report (2006)

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See detailExpertise du projet sur le site Rom (Eupen)
Merenne-Schoumaker, Bernadette ULg; Halleux, Jean-Marie ULg; Snoeck, E.

Report (1995)

Detailed reference viewed: 11 (0 ULg)