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See detailThe prediction of fund failure through performance diagnostics
Cogneau, Philippe ULg; Hübner, Georges ULg

in Journal of Banking and Finance (2015), 50

Using an international database featuring 1624 mutual funds over 15 years, this paper analyses the joint abilities of performance measures to predict subsequent fund failure. We examine the probability of ... [more ▼]

Using an international database featuring 1624 mutual funds over 15 years, this paper analyses the joint abilities of performance measures to predict subsequent fund failure. We examine the probability of disappearance over a time window, and expected fund survival time, and study the circumstances of a fund’s disappearance, its currency and domicile. By combining relevant measures, fund failure appears to a significant extent predictable, more than with single classical measures. Survivorship predictability has significant economic value. Such evidence suggests that past performance does not only influence investors’ perception of fund quality, but also reflects managers’ ability to sustain performance. [less ▲]

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See detailThe Harmonic Balance Method for Bifurcation Analysis of Nonlinear Mechanical Systems
Detroux, Thibaut ULg; Renson, Ludovic ULg; Masset, Luc ULg et al

in Proceedings of the SEM IMAC XXXIII (2015)

Because nowadays structural engineers are willing to use or at least understand nonlinearities instead of simply avoiding them, there is a need for numerical tools performing analysis of nonlinear large ... [more ▼]

Because nowadays structural engineers are willing to use or at least understand nonlinearities instead of simply avoiding them, there is a need for numerical tools performing analysis of nonlinear large-scale structures. Among these techniques, the harmonic balance (HB) method is certainly one of the most commonly used to study finite element models with reasonably complex nonlinearities. However, in its classical formulation the HB method is limited to the approximation of periodic solutions. For this reason, the present paper proposes to extend the method to the detection and tracking of codimension-1 bifurcations in the system parameters space. As an application, the frequency response of a spacecraft is studied, together with two nonlinear phenomena, namely quasiperiodic oscillations and detached resonance curves. This example illustrates how bifurcation tracking using the HB method can be employed as a promising design tool for detecting and eliminating such undesired behaviors. [less ▲]

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See detailCan meandering flows in shallow rectangular reservoir be modelled with the 2D shallow water equations?
Peltier, Yann ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in Journal of Hydraulic Engineering (2015)

In this article, the ability of the 2D shallow water equations to model meandering flows in shallow rectangular reservoirs is discussed. Four meandering flows, of various shallowness, were modelled using ... [more ▼]

In this article, the ability of the 2D shallow water equations to model meandering flows in shallow rectangular reservoirs is discussed. Four meandering flows, of various shallowness, were modelled using the academic flow model WOLF 2D, which includes a depth-averaged k- model accounting for the horizontal and vertical turbulent length-scales. The bottom friction was modelled with the Colebrook-White formula and different roughness heights were considered. A Proper Orthogonal Decomposition (POD) was applied to the simulation results to extract the behaviour of the main structures responsible for the meandering flow. The same POD analysis was also performed for the reference experimental flow fields, obtained by Large-Scale Particle Image Velocimetry. The first two POD modes obtained from the numerical simulations assuming a smooth bottom are in good agreement with the experimental modes in terms of energy, as well as temporal and spatial variations, whatever the shallowness. In contrast, the remaining simulated modes are not well rendered. The effect of an increased roughness height in the simulations is finally discussed. It leads to an improved reproduction of the first two modes and of the following modes, except when significant viscous effects govern in the flow. [less ▲]

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See detailVoyage(s) à travers le thymus
Geenen, Vincent ULg

Book published by Presses ULg (2015)

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See detailComparative biogeochemistry-ecosystem-human interactions on dynamic continental margins
Levin, Lisa A.; Liu, Kon-Kee; Kay-Christian, Emeis et al

in Journal of Marine Systems (2015), 141

The ocean’s continental margins face strong and rapid change, forced by a combination of direct human activity, anthropogenic CO2-induced climate change, and natural variability. Stimulated by discussions ... [more ▼]

The ocean’s continental margins face strong and rapid change, forced by a combination of direct human activity, anthropogenic CO2-induced climate change, and natural variability. Stimulated by discussions in Goa, India at the IMBER IMBIZO III, we (1) provide an overview of the drivers of biogeochemical variation and change on margins, (2) compare temporal trends in hydrographic and biogeochemical data across different margins (3) review ecosystem responses to these changes, (4) highlight the importance of margin time series for detecting and attributing change and (5) examine societal responses to changing margin biogeochemistry and ecosystems. We synthesize information over a wide range of margin settings in order to identify the commonalities and distinctions among continental margin ecosystems. Key drivers of biogeochemical variation include long-term climate cycles, CO2-induced warming, acidification, and deoxygenation, as well as sea level rise, eutrophication, hydrologic and water cycle alteration, changing land use, fishing, and species invasion. Ecosystem responses are complex and impact major margin services including primary production, fisheries production, nutrient cycling, shoreline protection, chemical buffering, and biodiversity. Despite regional differences, the societal consequences of these changes are unarguably large and mandate coherent actions to reduce, mitigate and adapt to multiple stressors on continental margins. [less ▲]

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See detailThe neural basis of temporal order processing in past and future thought
D'Argembeau, Arnaud ULg; Jeunehomme, Olivier ULg; Majerus, Steve ULg et al

in Journal of Cognitive Neuroscience (2015), 27

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See detailDilthey et l'empirisme psychologique
Dewalque, Arnaud ULg

in Camilleri, Sylvain; Fagniez, Guillaume (Eds.) Dilthey et l'histoire (2015)

Je discute ici le projet diltheyen d'une "fondation psychologique des sciences de l'esprit". Je suggère que ce projet peut être rapproché d’un certain programme épistémologique baptisé "empirisme ... [more ▼]

Je discute ici le projet diltheyen d'une "fondation psychologique des sciences de l'esprit". Je suggère que ce projet peut être rapproché d’un certain programme épistémologique baptisé "empirisme psychologique". L’hypothèse qui se trouve à la base de l’empirisme psychologique est la suivante : l’expérience interne, psychologique, est la source des concepts au moyen desquels nous pouvons penser et connaître le monde. Après avoir brièvement reconstruit le programme diltheyen en ce sens, j'examine deux objections qui ont été soulevées contre lui: l'objection néokantienne (Windelband, Rickert) et l'objection psychologique (Ebbinghaus, Stumpf). La seconde, selon moi, met en évidence une difficulté réelle du projet de Dilthey: la "connexion structurelle de la vie" dans sa totalité peut difficilement être considérée comme "donnée" dans l'expérience interne, ainsi que l'affirme Dilthey. Je soutient donc que le programme de l'empirisme psychologique peut être poursuivi à condition de le débarrasser de cette thèse problématique. [less ▲]

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See detailInvolvement of the Distinctiveness Heuristic in Children's Decision Making
Geurten, Marie ULg; Willems, Sylvie ULg; Meulemans, Thierry ULg

in International Convention of Psychological Science: ICPS, Amsterdam 2015 (2015)

Over the past decades, researchers studying adult metacognition have placed a heavy emphasis on how expectations and naïve theories about memory functioning can improve memory accuracy through the ... [more ▼]

Over the past decades, researchers studying adult metacognition have placed a heavy emphasis on how expectations and naïve theories about memory functioning can improve memory accuracy through the implementation of some metacognitive rules. By contrasts, however, research on metacognition in children has only recently started to pay attention to the influence of these heuristic-based judgments on decision making. Generally, the results of these studies indicate that memory decisions are already based on some heuristics by the ages of 7-8 years. Thus far, the question of whether younger children can do the same has widely gone unexamined. The present experiment investigates whether young children are able to reduce their false recognitions rate after distinctive encoding through the implementation of a strategic metacognitive rule. Specifically, we examine the use of a retrieval strategy called the distinctiveness heuristic whereby people infer that an event has not occurred when they cannot remember expected memorial information about it. Seventy-two children, aged 4, 6, and 9 years, studied two lists of unrelated items. One of these lists was visually displayed (picture/dictinctive condition) while the other was presented auditorily (word/no-distinctive condition). After each study phase, participants completed recognition tests. Finally, they answered questions about their explicit knowledge of the distinctive-encoding effect. The results revealed that even the youngest children in our sample showed a smaller proportion of intrusions in the picture condition than in the word condition. Furthermore, the findings of the signal detection analyses are consistent with the hypothesis that the lower rate of false recognitions after picture encoding results from the implementation of a conservative response criterion based on the participants’ metacognitive expectations (distinctiveness heuristic). Moreover, the absence of correlation between children’s explicit knowledge of the distinctiveness rule and their effective use of this metacognitive heuristic seems to indicate that its involvement in memory decisions could be mediated by implicit mechanisms. [less ▲]

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See detailSupervised inference of biological networks with trees : Application to genetic interactions in yeast
Schrynemackers, Marie ULg

Doctoral thesis (2015)

Networks or graphs provide a natural representation of molecular biology knowledge, in particular to model relationships between biological entities such as genes, proteins, drugs, or diseases. Because of ... [more ▼]

Networks or graphs provide a natural representation of molecular biology knowledge, in particular to model relationships between biological entities such as genes, proteins, drugs, or diseases. Because of the effort, the cost, or the lack of the experiments necessary to the elucidation of these networks, computational approaches for network inference have been frequently investigated in the literature. In this thesis, we focus on supervised network inference methods. These methods exploit supervised machine learning algorithms to train a model for identifying new interacting pairs of nodes from a training sample of known interacting and possibly non-interacting pairs and additional measurement data about the network nodes. Our contributions in this area are divided into three parts. First, the thesis examines the problem of the assessment of supervised network inference methods. Indeed, their reliable validation (in silico) poses a number of new challenges with respect to standard classification problems, related to the fact that pairs of objects are to be classified and to the specificities of biological networks. We perform a critical review and assessment of protocols and measures proposed in the literature. Through theoretical considerations and in silico experiments, we analyze in depth how important factors influence the outcome of performance estimation. These factors include the amount of information available for the interacting entities, the sparsity and topology of biological networks, and the lack of experimentally verified non-interacting pairs. From this analysis, we derived specific guidelines so as to how best exploit and evaluate machine learning techniques for network inference. Second, we systematically investigate, theoretically and empirically, the exploitation of tree- based methods for network inference. We consider these methods in the context of the two main generic classification-based approaches for network inference: the local approach, which trains a separate model for each network node, and the global approach, which trains a single model over pairs of nodes. We present and formalize these two approaches, extending the former for the prediction of interactions between two unseen network nodes, and discuss their specializations to tree-based methods, highlighting their interpretability and drawing links with clustering techniques. Extensive experiments are carried out with these methods on various biological networks that clearly highlight that these methods are competitive with existing methods. The interpretability of the resulting method family is illustrated on a drug-protein interaction network. In the last part of the thesis, we built on the experience gained in the two previous parts to try to predict at best the genetic interaction network in yeast S.cerevisiae. For that purpose, we collected a large dataset, assembling 4 millions gene pairs that were experimentally tested in the context of 11 different studies and 23 sets of measurements to use as gene input features for the inference. Through several cross-validation experiments on the resulting dataset, we showed that predicting genetic interactions is indeed possible to some useful extent and that actually in some settings, the accuracy of computational methods is not very far from that of experimental techniques. [less ▲]

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See detailConcept et perception
Gauvry, Charlotte ULg; Brisart, Robert

Book published by Olms (2015)

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See detailIntroduction
Fallon, Catherine ULg

in Albarello, Luc; Fallon, Catherine; Van Haeperen, Beatrice (Eds.) Evaluation des politiques publiques (2015)

Ce livre s’adresse à toutes les personnes qui a des titres divers sont concernés par l’évaluation des politiques publiques parce qu’ils doivent en assurer la réalisation ou en encadrer la démarche. Les ... [more ▼]

Ce livre s’adresse à toutes les personnes qui a des titres divers sont concernés par l’évaluation des politiques publiques parce qu’ils doivent en assurer la réalisation ou en encadrer la démarche. Les exemples et les angles de discussion sont les plus larges possibles pour que le lecteur puisse s’approprier les outils quel que soit son secteur de responsabilité et quel que soit son territoire. Il trouvera dans la suite des chapitres non pas un livre de recettes – ce qui nous semble contraire à la logique d’évaluation de politiques – mais des cadres de réflexion, des propositions de pratiques, ainsi que des références complémentaires pour développer ses pratiques tout en mobilisant un regard critique. [less ▲]

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See detailMagnetic shielding performances of YBa2Cu3O7−δ -coated silver tubes obtained by electrophoretic deposition
Devendra Kumar, N; Closset, Raphaël ULg; Wera, Laurent ULg et al

in Superconductor Science and Technology (2015), 28

We report a complete procedure to achieve multilayer YBCO thick films by electrophoretic deposition on silver tubes using a suspension of YBCO powder in butanol. With the aim to optimize the magnetic ... [more ▼]

We report a complete procedure to achieve multilayer YBCO thick films by electrophoretic deposition on silver tubes using a suspension of YBCO powder in butanol. With the aim to optimize the magnetic shielding performances of the coatings, we have carried out an extensive investigation of the influence of the deposition parameters, the multilayer deposition sequence and the intermediate/final heat treatments on the coating microstructure. Using the optimized conditions, a 24-layer YBCO coating has been successfully prepared on an 80 mm long Ag tube: the melt growth processed multilayered YBCO thick film thus obtained can shield an applied magnetic field of 1.9 mT at 77 K, the highest value per thickness unit reported so far in the literature for these materials. [less ▲]

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See detailPrevalence and prognosis of Alzheimer’s disease at the mild cognitive impairment stage
Vos; VERHEY, F.; Frölich, L. et al

in Brain : A Journal of Neurology (2015)

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See detailSartre in Venedig: der Mann, der in die Kälte ging
Cormann, Grégory ULg; Viehöver, Vera ULg

in Bulletin d'Analyse Phénoménologique (2015), 11

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See detail"Passer la ligne" : La rencontre de Fanon et de Sartre
Cormann, Grégory ULg

in Luneau, Marie-Pier; Saint-Amand, Denis (Eds.) La Préface. Formes, enjeux et effets d’un discours d’escorte (2015)

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See detailLectures de La Reine Albemarle ou le dernier touriste. Ontologie, autobiographie, politique
Cormann, Grégory ULg

in Bulletin d'Analyse Phénoménologique (2015), 11(1),

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See detailDoes reward unpredictability reflect risk?
Anselme, Patrick ULg

in Behavioural Brain Research (2015), 280(1), 119-127

Most decisions made in real-life situations are risky because they are associated with possible negative consequences. Current models of decision-making postulate that the occasional, unpredictable ... [more ▼]

Most decisions made in real-life situations are risky because they are associated with possible negative consequences. Current models of decision-making postulate that the occasional, unpredictable absence of reward that may result from free choice is a negative consequence interpreted as risk by organisms in laboratory situations. I argue that such a view is difficult to justify because, in most experimental paradigms, reward omission does not represent a cost for the decision maker. Risk only exists when unpredictability may cause a potential loss of own limited resources, whether energetic, social, financial, and so on. Thus the experimental methodologies used to test humans and non-humans relative to risk-taking seem to be limited to studying the effects of reward uncertainty in the absence of true decision cost. This may have important implications for the conclusions that can be drawn with respect to the neurobehavioural determinants of risk-taking in real-life situations. [less ▲]

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See detailFe–Ti–V–P ore deposits associated with Proterozoic massif-type anorthosites and related rocks
Charlier, Bernard ULg; Namur, Olivier; Bolle, Olivier ULg et al

in Earth-Science Reviews (2015), 141(0), 56-81

Magmatic rocks containing economic concentrations of iron, titanium, vanadium and phosphorous are commonly associated with massif-type anorthosites and related rocks. This rock association is part of the ... [more ▼]

Magmatic rocks containing economic concentrations of iron, titanium, vanadium and phosphorous are commonly associated with massif-type anorthosites and related rocks. This rock association is part of the anorthosite–mangerite–charnockite–(rapakivi-)granite suites that are restricted to the Proterozoic. Understanding the geochemistry and emplacement mechanisms of ilmenite, magnetite and apatite ore deposits is crucial for exploration, efficient mining operations and ore processing. This review discusses the controlling factors on the grade of an ore, its mineralogy, and its major and trace element distribution. We present petrogenetic models of currently mined deposits (Lac Tio, Tellnes, Damiao) and discuss the characteristics of minor ore bodies from anorthosite provinces worldwide (Grenville, North China Craton, East European Craton, Rogaland, Laramie). Models of formation of anorthosite and related rocks are presented, as well as the nature of the possible parental magmas of the suite. A mineralogical classification of Fe–Ti ores is proposed: (1) Gabbro-noritic ilmenite ore ± apatite ± magnetite; (2) Ti-magnetite-dominated ore; (3) Nelsonite (Fe–Ti oxides + apatite); and (4) Rutile-ilmenite ore. The stability of ilmenite and magnetite is then critically reviewed and the influence of various factors, particularly oxygen fugacity and crystallization pressure, is examined. We discuss liquidus compositions of Fe–Ti oxides and the behavior of important trace elements such as Cr and V, both of which are sensitive to fO2 variations. Post-cumulus evolution of both oxides can occur due to re-equilibration with trapped liquid, re-equilibration with ferromagnesian silicates, exsolution, oxidation, reaction between ilmenite and magnetite, and metamorphic overprinting. These various processes are described and their effects on the oxide geochemistry are emphasized. Several potential ore-forming processes have been invoked and can explain the formation of huge concentration of ilmenite, ± magnetite, ± apatite. Fractional crystallization can be combined with crystal sorting and plagioclase buoyancy to produce relative enrichment of dense ore minerals. Silicate liquid immiscibility can segregate conjugate Si-rich and Fe-rich melts, the latter being enriched in Fe–Ti–P. Magma mixing can produce hybrid magmas located in a single-phase field of the phase diagram and precipitate a pure ilmenite cumulate. Alternative processes are also described, such as ejection of Fe–Ti-enriched residual melts by filter-pressing and compaction, solid-state remobilization of ilmenite in veins, and hydrothermal transport of Fe and Ti from the host anorthosite followed by concentration in veins and lenticular ore bodies. The magnetic properties of Fe–Ti ore deposits present contrasting signatures, depending on whether the natural remanent magnetization is dominated by hemo-ilmenite or multi-domain magnetite. Micro- and macro-scale deformation features of ore rocks are intimately correlated with magma emplacement, and with ballooning of the anorthosite diapir associated with gravitational sagging of dense ore bodies. Exploration perspectives show that oxide-apatite gabbronorites are interesting targets because ilmenite in these rocks is poorer in Cr and Mg, and because the Ti-resource may be combined with apatite and vanadiferous magnetite. [less ▲]

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See detailSartre et l'instinct de mort
Cormann, Grégory ULg

in Gyemant, Maria; Popa, Delia (Eds.) Approches phénoménologiques de l'inconscient (2015)

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