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See detailDu définitif sur du provisoire...
Englebert, Jérôme ULg; Follet, Valérie

Conference (2017, May 18)

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See detailRadiohead and Prog Rock
Delville, Michel ULg

Conference (2017, May 18)

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See detailApplication of wavelet transforms to geosciences: Extraction of functional and frequential information
Deliège, Adrien ULg

Doctoral thesis (2017)

It is now well-known that there exist functions that are continuous but nowhere differentiable. Still, it appears that some of them are less “irregular” than others. The pointwise regularity of a function ... [more ▼]

It is now well-known that there exist functions that are continuous but nowhere differentiable. Still, it appears that some of them are less “irregular” than others. The pointwise regularity of a function can be characterized by its Hölder exponent at each point. For the sake of practicability, it is more appropriate to determine the “size” of the sets of points sharing a same exponent, through their Hausdorff measure. By doing so, one gets the multifractal spectrum of a function, which characterizes in particular its monofractal or multifractal nature. The first part of this work is based on the so-called “wavelet leaders method” (WLM), recently developed in the context of multifractal analysis, and aims at its application to concrete situations in geosciences. First, we present the WLM and we insist particularly on the major differences between theory and practice in its use and in the interpretation of the results. Then, we show that the WLM turns out to be an efficient tool for the analysis of Mars topography from a unidimensional and bidimensional point of view; the first approach allowing to recover information consistent with previous works, the second being new and highlighting some areas of interest on Mars. Then, we study the regularity of temperature signals related to various climate stations spread across Europe. In a first phase, we show that the WLM allows to detect a strong correlation with pressure anomalies. Then we show that the Hölder exponents obtained are directly linked to the underlying climate and we establish criteria that compare them with their climate characteristics as defined by the Köppen-Geiger classification. On the other hand, the continuous version of the wavelet transform (CWT), developed in the context of time-frequency analysis, is also studied in this work. The objective here is the determination of dominant periods and the extraction of the associated oscillating components that constitute a given signal. The CWT allows, unlike the Fourier transform, to obtain a representation in time and in frequency of the considered signal, which thus opens new research perspectives. Moreover, with a Morlet-like wavelet, a simple reconstruction formula can be used to extract components. Therefore, the second part of the manuscript presents the CWT and focuses mainly on the border effects inherent to this technique. We illustrate the advantages of the zero-padding and introduce an iterative method allowing to alleviate significantly reconstruction errors at the borders of the signals. Then, we study in detail the El Niño Southern Oscillation (ENSO) signal related to temperature anomalies in the Pacific Ocean and responsible for extreme climate events called El Niño (EN) and La Niña (LN). Through the CWT, we distinguish its main periods and we extract its dominant components, which reflect well-known geophysical mechanisms. A meticulous study of these components allows us to elaborate a forecasting algorithm for EN and LN events with lead times larger than one year, which is a much better performance than current models. After, we generalize the method used to extract components by developing a procedure that detects ridges in the CWT. The algorithm, called WIME (Wavelet-Induced Mode Extraction), is illustrated on several highly non-stationary examples. Its ability to recover target components from a given signal is tested and compared with the Empirical Mode Decomposition. It appears that WIME has a better adaptability in various situations. Finally, we show that WIME can be used in real-life cases such as an electrocardiogram and the ENSO signal. [less ▲]

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See detailImplementation of SFC for the quality control of pharmaceuticals
Dispas, Amandine ULg; Andri, Bertyl ULg; Lebrun, Pierre ULg et al

Conference (2017, May 17)

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See detailLe manuel de grammaire latine de Dosithée : quelle méthode d'apprentissge ?
Rochette, Bruno ULg

Conference (2017, May 15)

Contrairement aux autres manuels de grammaire latine destinés aux hellénophones, comme ceux de Charisius, Diomède et Priscien qui travaillent dans la pars Orientis pour des hellénophones, l’Ars grammatica ... [more ▼]

Contrairement aux autres manuels de grammaire latine destinés aux hellénophones, comme ceux de Charisius, Diomède et Priscien qui travaillent dans la pars Orientis pour des hellénophones, l’Ars grammatica de Dosithée est accompagnée d’une traduction grecque. La présence de cette traduction, qui ne concerne toutefois pas toute la grammaire, mais seulement environ la moitié du texte, singularise ce manuel dans la tradition des artes, même si nous ne pouvons exclure que d’autres traités grammaticaux du même type n’aient pas été accompagnés d’une traduction grecque que nous n’aurions pas conservée. Quoi qu’il en soit, le statut de cette traduction est assez difficile à établir. Essentiellement deux questions se posent à son sujet : quel est son auteur, est-ce Dosithée lui-même ou un utilisateur plus tardif (éventuellement dans le monde occidental), et à quoi sert-elle ? Il apparaît clairement que le grec doit aider à la compréhension du latin, non le remplacer. La traduction grecque n’a donc pas une vocation à l’autonomie. Elle n’a de sens qu’en relation avec le latin. La traduction semble se réduire au fur et à mesure que l’on avance dans la grammaire. Il semble que Dosithée attende de l’utilisateur de la grammaire qu’il ait de moins en moins besoin d’aide à mesure qu’il progresse dans l’apprentissage. J’analyse la nature du grec de Dosithée en vue de mieux comprendre la méthode d’apprentissage mise en œuvre dans ce manuel. Bibliographie Bonnet G., Dosithée. Grammaire latine, Paris, CUF, 2005. --, La version grecque de l’Ars de Dosithée, dans L. Basset-Fr. Biville-B. Colombat-P. Swiggers-A. Wouters (éds), Bilinguisme et terminologie grammaticale gréco-latine, Leuven-Paris-Dudley, 2007, p. 191-199. Dickey E., The Authorship of the Greek Version of Dositheus’ Grammar and What it Tells Us about the Grammar’s Original Use, dans R. Ferri-A. Zago (eds), The Latin of the Grammarians. Reflections about Language in the Roman World, Turnhout, 2016, p. 205-235. --, Learning Latin. The Ancient Way. Latin Textbooks from the Ancient World, Cambridge, 2016. Lenoble M. – Swiggers P. – Wouters P., L’enseignement grammatical entre grec et latin : le manuel de Dosithée, P. Desmet-L. Jooken-P. Schmitter-P. Swiggers (eds), The History of Linguistic and Grammatical Praxis. Proceedings of the XIth International Colloquium of the Studienkreis « Geschichte der Sprachwissenschaft » (Leuven, 2nd – 4th July, 1998), Leuven-Paris-Sterling, 2000, p. 3-22. Reichamnn V., Römische Literatur in griechischer Übersetzung, Leipzig, 1943. J. Tolkiehn J., Dosithei Ars Grammatica, Leipzig, 1913. [less ▲]

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See detailBelgian speleothem records Holocene cold events?
Allan, Mohammed ULg; Deliège, Adrien ULg; Nicolay, Samuel ULg et al

Poster (2017, May 12)

Speleothem is now regarded as valuable archive of climatic conditions on the continents, offering a number of advantages relative to other continental climate proxy recorders such as lake sediments and ... [more ▼]

Speleothem is now regarded as valuable archive of climatic conditions on the continents, offering a number of advantages relative to other continental climate proxy recorders such as lake sediments and peat cores. High spatial resolution measurements of Mg, Al, Sr, Ba were realized by using laser-ablation inductively coupled plasma mass spectrometry in the Belgian Pere Noel cave. A stalagmite from the Pere Noel (PN) cave representing 12000 years dated by U/Th method. Trace element variations in speleothem are a reflection of hydrochemical conditions. These changes were interpreted as indications of changes in climate in the Han-sur-Lesse region. The similar patterns found in δ 18O, δ 13C and chemical composition along the Pere Noel stalagmite suggests that trace elements in speleothems have the potential to provide high resolution insights into palaeoclimatic variability during the Holocene. A deeper analysis reveals several periods of significant rapid climate change during the Holocene (at 10.7-9.2 ka, 8.2-7.9 ka, 7.2-6.2 ka, 4.8-4.5 ka, and 3-2.4 ka BP), which are similar to the cold events detected from different natural paleoclimate archivers. A comparison between the geochemical analysis of Père Noël speleothem and solar activity (sunspot number) reveals a significant correlation. Spectral analysis methods reveal common solar periodicities (Gleissberg cycle, de Vries cycle, unnamed 500 year, Eddy cycles, and Hallstatt cycle). The geochemical analyses have the potential to prove that PN speleothem is sensitive to changes in solar activity on centennial and millennial timescales during the Holocene. [less ▲]

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See detailLes constructions relatives du néo-égyptien. Une approche fonctionnelle
Sojic, Nathalie ULg

Doctoral thesis (2017)

Cette dissertation doctorale se propose d’étudier les constructions relatives du néo-égyptien suivant une approche fonctionnelle. Elle offre une première étude large de la relativisation pour cet état de ... [more ▼]

Cette dissertation doctorale se propose d’étudier les constructions relatives du néo-égyptien suivant une approche fonctionnelle. Elle offre une première étude large de la relativisation pour cet état de langue sous l’angle de la variation linguistique. Elle comprend deux grandes parties : les chapitres 1 à 4 sont théoriques, les chapitres 5 à 9 constituent la recherche à proprement parler. Le chapitre 10 conclut l’ensemble. Le premier chapitre (Ch. 1) propose un état de la question des études relatives aux constructions relatives en égyptien ancien et met en avant le manque criant de vision d’ensemble des descriptions et des études proposées jusqu’à présent, tous états de langue confondus. Le chapitre suivant (Ch. 2) définit le cadre théorique dans lequel s’inscrit l’étude, à savoir les bases conceptuelles et terminologiques issues du fonctionnalisme en linguistique. J’y fais également le point sur le recours, en égyptologie, à ces théories. Le troisième chapitre (Ch. 3) est consacré à la délimitation et à la description du corpus, l’accent étant mis sur la variation linguistique (en diachronie et en synchronie dynamique). Je propose ensuite (Ch. 4) un préambule ou un excursus relatif à la définition des « parties du discours », catégories d’après lesquelles sont classées les unités qui composent la phrase. La plupart des études fonctionnelles, dont la présente, ont pour objet l’une de ces catégories. Le cinquième chapitre (Ch. 5) offre une vue d’ensemble des constructions relatives et constructions apparentées en égyptien ancien (ancien, moyen et néo). La description, très générale, vise à rendre compte de leurs principales caractéristiques typologiques et des particularités de la langue étudiée. Le chapitre suivant (Ch. 6) est consacré à l’histoire du système : il en présente les grandes tendances distributionnelles aux stades de la langue antérieurs au néo-égyptien. Cette synthèse montre l’existence de jeux d’oppositions à l’œuvre à une époque donnée et permet d’en constater l’évolution au stade concerné. Dans un autre chapitre, (Ch. 7) j’examine en détail l’expression de la négation dans les relatives. Après y avoir exposé les facteurs de variation spécifique à l’évolution de la négation, je propose une taxonomie fonctionnelle des constructions relatives négatives en néo-égyptien. Plus loin (Ch. 8), je me penche sur l’épineuse question de la valeur sémantique des relatives introduites par nty (« vraies » relatives) et de celles introduites par iw (relatives « virtuelles », c’est-à-dire des circonstancielles fonctionnant comme des relatives). Ma démarche, issue d’une réflexion critique à partir des études menées sur les différents types de relatives dans d’autres langues, m’amène à suggérer que, contrairement à ce qui a été dit pour l’égyptien ancien, leur distribution ne dépend pas uniquement de la définition de l’antécédent ou de la nature du relateur, mais que la valeur sémantique – contingente ou non – de la construction relativisée joue un rôle tout aussi important. Cette nouvelle façon d’aborder le problème permet d’apporter une explication quant à la grammaticalisation observée dans la distribution de ces constructions. L’avant dernier chapitre (Ch. 9) propose une étude approfondie de l’omission du pronom de rappel de l’antécédent dans les relatives du néo-égyptien. J’y recours aux concepts d’échelle d’accessibilité à la relativisation élaborée par Keenan & Comrie (1977), d’échelle d’accessibilité cognitive d’Ariel (1990) et aux travaux d’Hawkins (1999, 2004) relatifs à la structure informationnelle de la phrase complexe. Ce faisant, je définis des contextes particulièrement favorables à une omission, et démontre aussi que ces omissions sont en partie motivées par des facteurs extralinguistiques. Le dernier chapitre (Ch. 10) fait office de conclusion générale. Il fait le point sur l’apport des chapitres précédents et sur les différents types de variations mis en évidence dans cette étude. [less ▲]

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See detailLes problématiques de l'adaptation et de l'intersubjectivité dans la psychothérapie
Englebert, Jérôme ULg

Scientific conference (2017, May 10)

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See detailHunger Art and the Sensorium
Delville, Michel ULg

Conference (2017, May 10)

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See detailIdentification of non-stationary dynamical systems using multivariate ARMA models
Bertha, Mathieu ULg; Golinval, Jean-Claude ULg

in Mechanical Systems and Signal Processing (2017), 88

This paper is concerned by the modal identification of time-varying mechanical systems. Based on previous works about autoregressive moving average models in vector form (ARMAV) for the modal ... [more ▼]

This paper is concerned by the modal identification of time-varying mechanical systems. Based on previous works about autoregressive moving average models in vector form (ARMAV) for the modal identification of linear time invariant systems, and time-varying autoregressive moving average models (TV-ARMA) for the identification of nonstationary systems, a time-varying ARMAV (TV-ARMAV) model is presented for the multivariate identification of time-varying systems. It results in the identification of not only the time-varying poles of the system but also of its respective time-varying mode shapes. The method is applied on a time-varying structure composed of a beam on which a mass is moving. [less ▲]

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See detailIn vitro biphasic dissolution tests and their suitability for establishing in vitro-in vivo correlations: A historical review
Pestieau, Aude ULg; Evrard, Brigitte ULg

in European Journal of Pharmaceutical Sciences (2017), 102

For many decades, one of the most critical issues in the pharmaceutical industry has been the poor solubility of some drugs. Indeed, a prerequisite for drug absorption is the presence of dissolved drug at ... [more ▼]

For many decades, one of the most critical issues in the pharmaceutical industry has been the poor solubility of some drugs. Indeed, a prerequisite for drug absorption is the presence of dissolved drug at the absorption site and this can be challenging for compounds with low aqueous solubility such as BCS class II (low solubility, high permeability) and IV (low solubility, low permeability) compounds. If the development of oral delivery formulations of these compounds is frequently challenging to formulation scientists in the pharmaceutical industry, the in vitro evaluation of these new formulations is also a great challenge. One alternative approach to overcome the problems encountered with conventional dissolution methods is the use of biphasic dissolution systems. This review provides an overview of the origin and the evolution over time of the biphasic systems and the growing interest among scientists regarding their suitability for establishing in vitro-in vivo correlations. The evolution of these systems and their applications from the 1960s to the present day, such as in system variants and improvements, analysis of complex formulations, discriminatory power, bio-relevance, precipitation and supersaturation visualization, etc. will be discussed. [less ▲]

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See detailCo-creating service recovery after service failure: The role of brand equity
Hazee, Simon ULg; Van Vaerenbergh, Yves; Armirotto, Vincent

in Journal of Business Research (2017), 74

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See detailFrom distant neighbours to bedmates: Exploring the synergies between the social economy and sustainable development
Hudon, Marek; Huybrechts, Benjamin ULg

in Annals of Public and Cooperative Economics (2017), 88(2),

To introduce this special issue we explore the conceptual and practical synergies between the social economy and sustainable development. New empirical evidence is presented on the emergence of these two ... [more ▼]

To introduce this special issue we explore the conceptual and practical synergies between the social economy and sustainable development. New empirical evidence is presented on the emergence of these two research fields and the increasing combination of these fields in the literature. Several avenues through which social enterprises can contribute to the transition towards sustainable development are then identified. This is followed by a discussion of how and why the combination can be particularly fruitful both for the social economy and for sustainability transition movements. We also highlight some important challenges facing the social economy with regard to its contribution to sustainable development. Finally we introduce the papers that constitute this special issue and show how they contribute, individually and collectively, to a better understanding of the increasing linkage between the social economy and sustainable development. [less ▲]

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See detailThe European Parliament as an actor in the global governance of culture: from voice to influence?
Vlassis, Antonios ULg

in Rioux, Michèle (Ed.) Culture, societies and digital technologies (2017)

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See detailFinite element model reduction for space thermal analysis
Jacques, Lionel ULg; Béchet, Eric ULg; Kerschen, Gaëtan ULg

in Finite Elements in Analysis and Design (2017), 127

To alleviate the computational burden of the nite element method for thermal analyses involving conduction and radiation, this paper proposes an automatic conductive-radiative reduction process based on ... [more ▼]

To alleviate the computational burden of the nite element method for thermal analyses involving conduction and radiation, this paper proposes an automatic conductive-radiative reduction process based on the clustering of a detailed mesh coming from a structural model for instance. The proposed method leads to a signi cant reduction of the number of radiative exchange factors (REFs) to compute and size of the corresponding matrix. It further keeps accurate conduction information by introducing the concept of physically meaningful super nodes. The REFs between the super nodes are computed through Monte Carlo ray-tracing on the partitioned mesh, preserving the versatility of the method. The resulting conductive-radiative reduced model is solved using standard iterative techniques and the detailed mesh temperatures can be recovered from the super nodes temperatures for further thermo-mechanical analysis. The proposed method is applied to a structural component of the Meteosat Third Generation mission and is benchmarked against ESATAN-TMS, the standard thermal analysis software used in the European aerospace industry. [less ▲]

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See detailProcess intensification of the synthesis of glycerol carbonate under microwave irradiation or continuous-flow conditions
Estager, Julien; Pleck, Julie; Gerardy, Romaric ULg et al

Conference (2017, May)

Despite low crude oil prices and the increasing access to shale gas, the establishment of a biobased economy remains a worldwide priority. An integrated biobased economy would not only consider renewable ... [more ▼]

Despite low crude oil prices and the increasing access to shale gas, the establishment of a biobased economy remains a worldwide priority. An integrated biobased economy would not only consider renewable biobased resources to provide industrially relevant chemicals, but would also redefine chemical processing by using greener, safer and more selective process technologies. The last few decades have witnessed the emergence of promising alternative energy sources such as microwave irradiation and alternative process technology such as continuous-flow reactors. Even if biobased chemicals are still marginal on the marklet compared to petrochemicals, many biorefineries are now able to convert biomass into biobased chemical building blocks of good purity on large scales. Amongst these products, glycerol – a side product of the biodiesel industry – is a particularly appealing chemical platform thanks to its high functionality and its wide availability. Various high-value added chemicals can be obtained from glycerol, among which glycerol carbonate retained our attention. Glycerol carbonate is an attractive glycerol derivative that can be used in many applications ranging from low-VOC solvent to polymer synthesis. Many publications describe its synthesis using different catalysts or alternative activation methods such as microwave. Our research effort in process intensification for the industrial valorization of biomass led us to develop an intensified carbonation process of glycerol under microwave irradiation, affording an unprecedented reactivity with short reaction times and high selectivity towards glycerol carbonate. Based on this preliminary study, and using the microwave-to-flow paradigm, continuous-flow processes using mesofluidic reactors have been developed to obtain glycerol carbonate in good yield and high purity. [less ▲]

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