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See detailAn overview of nonintrusive characterization, propagation, and sensitivity analysis of uncertainties in computational mechanics
Arnst, Maarten ULg; Ponthot, Jean-Philippe ULg

in International Journal for Uncertainty Quantification (in press)

In this paper, we offer a short overview of a number of methods that have been reported in the computational-mechanics literature for quantifying uncertainties in engineering applications. Within a ... [more ▼]

In this paper, we offer a short overview of a number of methods that have been reported in the computational-mechanics literature for quantifying uncertainties in engineering applications. Within a probabilistic framework, we describe the characterization of uncertainties using mathematical statistics methods, the propagation of uncertainties through computational models using either Monte Carlo sampling or stochastic expansion methods, and the sensitivity analysis of uncertainties using variance- and differentiation-based methods. We restrict our attention to nonintrusive methods that can be implemented as wrappers around existing computer programs, thus requiring no modification of the source code. We include some recent advances in the propagation and sensitivity analysis of uncertainties that are characterized by arbitrary probability distributions that may exhibit statistical dependence. Finally, we demonstrate the methods integrated in the proposed overview through a nonlinear engineering application relevant to metal forming. [less ▲]

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See detailEffet du mode de conservation d’huile de Jatropha curcas L. sur son efficacité dans la lutte contre les principaux insectes ravageurs du niébé (Vigna unguiculata (L.) Walp. au Niger
Abdoul Habou, zakari; Toudou, Adam; Haubruge, Eric ULg et al

in Tropicultura (in press)

Jatropha curcas oil has an insecticidal activity harnessed by the farmers in Niger. In this study, we compared the insecticidal activity of two batches of oil conserved during 70 days, one exposed to ... [more ▼]

Jatropha curcas oil has an insecticidal activity harnessed by the farmers in Niger. In this study, we compared the insecticidal activity of two batches of oil conserved during 70 days, one exposed to light and the other kept in the dark. The insecticidal efficacy was evaluated in a field with three concentrations (5, 10 and 15%) trial on the main pests of Cowpea (Vigna unguiculata (L.) Walp) and in a laboratory test on Megalurothrips sjostedti Trybon (Thysanoptera: Thripidae) with different concentrations of crude oil (50; 100; 150 and 200 µl). No difference in insecticidal effect was found between the two modes of oil conservation, both in the laboratory and in the field. In the field, regardless of the mode of conservation, the concentrations of 10% of J. curcas oil enables a reduction of over than 80% of thrips, aphids, and bugs compared to the control. Its increased seeds yield more than 50%. The concentration of 15% gives an insecticidal effect comparable to that of the reference treatment (deltaméthrine) but induces phytotoxicity symptoms on the leaves of Cowpea. [less ▲]

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See detailVom Nutzen massenhaften Laienwissens für die Erforschung von Strukturen der Alltagssprache
Elspaß, Stephan; Möller, Robert ULg

in Bühler, Rudolf; Bürkle, Rebekka; Leonhardt, Nina Kim (Eds.) Sprachkultur – Regionalkultur: Neue Felder kulturwissenschaftlicher Dialektforschung. (in press)

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See detailL'antipsychologisme de Brentano
Boccaccini, Federico ULg

in Gyemant, Maria (Ed.) Psychologie et psychologisme (in press)

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See detailA mysterious giant ichthyosaur from the lowermost Jurassic of Wales
Martin, Jeremy; Vincent, Peggy; Suan, Guillaume et al

in Acta Palaeontologica Polonica (in press)

Ichthyosaurs rapidly diversified and colonised a wide range of ecological niches during the Early and Middle Triassic period, but experienced a major decline in diversity near the end of the Triassic ... [more ▼]

Ichthyosaurs rapidly diversified and colonised a wide range of ecological niches during the Early and Middle Triassic period, but experienced a major decline in diversity near the end of the Triassic. Timing and causes of this demise and the subsequent rapid radiation of the diverse, but less disparate, parvipelvian ichthyosaurs are still unknown, notably because of inadequate sampling in strata of latest Triassic age. Here, we describe an exceptionally large radius from Lower Jurassic deposits at Penarth near Cardiff, South Wales (UK) the morphology of which places it within the giant Triassic shastasaurids. A tentative total body size estimate, based on a regression analysis of various complete ichthyosaur skeletons, yields a value of 12-15 m. The specimen is substantially younger than any previously reported last known occurrences of shastasaurids and implies a Lazarus range in the lowermost Jurassic for this ichthyosaur morphotype. [less ▲]

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See detailChronique bibliographique - Supplément 2005-2008
Veymiers, Richard ULg; Bricault, Laurent; Malaise, Michel et al

in Bricault, Laurent; Veymiers, Richard (Eds.) Bibliotheca Isiaca III (in press)

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See detailDevonian antiarch placoderms from Belgium revisited
Olive, Sébastien ULg

in Acta Palaeontologica Polonica (in press)

Anatomical, systematic, and paleobiogeographical data on the Devonian antiarchs from Belgium are reviewed, updated and completed thanks to new data from the field and re-examination of paleontological ... [more ▼]

Anatomical, systematic, and paleobiogeographical data on the Devonian antiarchs from Belgium are reviewed, updated and completed thanks to new data from the field and re-examination of paleontological collections. The material of Bothriolepis lohesti Leriche, 1931 is enhanced and the species better described. An undetermined species of Bothriolepis is recorded from the Famennian of Modave (Liège Province), one species of Asterolepis redescribed from the Givetian of Hingeon and another one described from the Givetian of Mazy (Namur Province). Grossilepis rikiki sp. nov. is recorded from the Famennian tetrapod-bearing locality of Strud (Namur Province) and from the Famennian of Moresnet (Liège Province). It is the first occurrence of Grossilepis after the Frasnian and on the central southern coast of the Euramerican continent. Its occurrence in the Famennian of Belgium may be the result of a late arrival from the Moscow Platform and the Baltic Depression, where the genus is known from Frasnian deposits. Remigolepis durnalense sp. nov. is described from the Famennian of Spontin near Durnal (Namur Province). Except for the doubtful occurrence of Remigolepis sp. in Scotland, this is the first record of this genus in Western Europe. Its occurrence in Belgium reinforces the strong faunal affinities between Belgium and East Greenland and the hypothesis of a hydrographical link between the two areas during the Late Devonian. [less ▲]

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See detailDynamic Simulations of Combined Transmission and Distribution Systems using Parallel Processing Techniques
Aristidou, Petros ULg; Van Cutsem, Thierry ULg

in Proceedings of the 18th PSCC (in press)

Simulating a power system with both transmission and distribution networks modeled in detail is a huge computational challenge. In this paper, we propose a Schur-complement-based domain decomposition ... [more ▼]

Simulating a power system with both transmission and distribution networks modeled in detail is a huge computational challenge. In this paper, we propose a Schur-complement-based domain decomposition algorithm to provide accurate, detailed dynamic simulations of the combined system. The simulation procedure is accelerated with the use of parallel programming techniques, taking advantage of the parallelization opportunities inherent in domain decomposition algorithms. The proposed algorithm is general, portable and scalable on inexpensive, shared-memory, multicore machines. A large-scale test system is used for its performance evaluation. [less ▲]

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See detailFin de siècle/Jahrhundertwende: Eine Tendenzgeschichte
Küpper, Achim ULg

in Roland, Hubert (Ed.) Eine kleine deutsch-französische Literaturgeschichte vom 18. Jahrhundert bis zum Ersten Weltkrieg (in press)

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See detailLes progrès de la poésie en 1867. Portrait de Gautier en grand rapporteur
Durand, Pascal ULg

in Saminadayar-Perrin, Corinne (Ed.) Théophile Gautier et l'invention médiatique de l'histoire littéraire (in press)

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See detailThe ideology of the British National Party
Jamin, Jérôme ULg

in Revue LISA : Littératures, Histoire des Idées, Images, Sociétés du Monde Anglophone = LISA e-Journal (in press)

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See detailSegregation distortions in an interspecific cotton population issued from the [(Gossypium hirsutum x G. raimondii)² x G. sturtianum] hybrid
Diouf, Fatimata Bintou Hassédine ULg; BENBOUZA, Halima; Nacoulima, Nafissatou Lalaïssa ULg et al

in Tropicultura (in press)

The segregation ratio of 10 Gossypium sturtianum specific SSR markers belonging to linkage groups c2-c14, c3-c17, and c6-c25was analysed in the BC2S6 progeny of the [G.hirsutum x G. raimondii)² x G ... [more ▼]

The segregation ratio of 10 Gossypium sturtianum specific SSR markers belonging to linkage groups c2-c14, c3-c17, and c6-c25was analysed in the BC2S6 progeny of the [G.hirsutum x G. raimondii)² x G. sturtianum] (HRS) hybrid; based on chi-square test. All the marker loci tested were associated with skewed allele frequencies (P < 0.001) showing a strong SD with a zygotic selection. The possible causes and consequences of this massive segregation distortion are discussed [less ▲]

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See detailA relaxation scheme to combine Phasor-Mode and Electromagnetic Transients Simulations
Plumier, Frédéric ULg; Aristidou, Petros ULg; Geuzaine, Christophe ULg et al

in Proceedings of the 18th Power System Computation Conference (in press)

This paper deals with a new scheme for coupling phasor-mode and electromagnetic transients simulations. In each simulation, an iteratively updated linear equivalent is used to represent the effect of the ... [more ▼]

This paper deals with a new scheme for coupling phasor-mode and electromagnetic transients simulations. In each simulation, an iteratively updated linear equivalent is used to represent the effect of the subsystem treated by the other simulation. Time interpolation and phasor extraction methods adapted to this scheme are presented and compared to existing methods. Finally, simulation results obtained with a 74-bus test system are reported. [less ▲]

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See detailJatropha curcas L. (Euphorbiaceae): Insectes ravageurs et propriétés biocides
Abdoul Habou, Zakari; Toudou, Adam; Haubruge, Eric ULg et al

in Biotechnologie, Agronomie, Société et Environnement = Biotechnology, Agronomy, Society and Environment [=BASE] (in press)

Jatropha curcas, ou Pourghère, est un arbuste de la famille des Euphorbiacées, largement répandu dans les pays tropicaux. Ses graines sont riches d'une huile pouvant servir de biocarburant dans les ... [more ▼]

Jatropha curcas, ou Pourghère, est un arbuste de la famille des Euphorbiacées, largement répandu dans les pays tropicaux. Ses graines sont riches d'une huile pouvant servir de biocarburant dans les moteurs diesels modifiés. La plante est attaquée par divers insectes ravageurs appartenant principalement aux ordres des Hétéroptères, Coléoptères et Orthoptères. Ils provoquent des dégâts sur les fruits, les inflorescences et les feuilles. Les ravageurs les plus fréquemment observés sur J. curcas sont des punaises du genre Pachycoris (Hétéroptère : Scutelleridae), qui sont largement répandues au Mexique, en Australie, aux États-Unis, au Brésil et au Nicaragua. Ces punaises causent des dégâts importants sur les fruits et provoquent la malformation des graines, et avec elle une réduction de la teneur en huile. Même si les arbustes de Jatropha sont victime d'infestations d'insectes, plusieurs études démontrent l'effet insecticide de son huile contre des ravageurs importants tels que Busseola fusca (Fuller) (Lépidoptère : Noctuidae), Sesamia calamistis Hampson (Lépidoptère : Noctuidae), Aphis gossypii Glover (Homoptère: Aphididae) et Callosobruchus chinensis L. (Coléoptère : Bruchidae). Dans ce document, nous présentons dans une première partie les principaux insectes ravageurs de J. curcas et dans une seconde section les effets insecticides démontrés de son huile. [less ▲]

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See detailA Double-Blind, Placebo Controlled, Randomized Trial to Assess the Impact of a Monthly Administration of 50,000 IU of Vitamin D3 for 6 Months on Serum Levels of 25-Hydroxyvitamin D in Healthy Young Adults
Brunel, Elodie ULg; SCHNITZLER, Maryline ULg; Foidart-Dessalle, Marguerite ULg et al

in International Journal of Endocrinology (in press)

In this double blind, unicentre, randomized, placebo controlled study, we evaluated the changes in 25-hydroxyvitamin D (25(OH)D) serum levels in 150 young Belgian adults (18–30 years), monthly ... [more ▼]

In this double blind, unicentre, randomized, placebo controlled study, we evaluated the changes in 25-hydroxyvitamin D (25(OH)D) serum levels in 150 young Belgian adults (18–30 years), monthly supplemented with 50,000 IU of vitamin D (VTD) or placebo for 6 months, from November 2010 to May 2011. At T0, 30% of the population presented 25(OH)D serum levels below 20 ng/mL. In the VTD-treated group, mean serum levels increased from 21.2 ± 8.2 to 30.6 ± 8.8 ng/mL (𝑃 < 0.001) at T3mo and to 36.0 ± 9.2 ng/mL (𝑃 < 0.001) at T6mo. Despite documented VTD intake, no changes in serum levels were, however, observed in 10% of the treated group. In the placebo group, mean 25(OH)D serum levels decreased from22.8 ± 8.5 to 14.0 ± 6.9 ng/mL at T3mo (𝑃 < 0.001) but returned to values not significantly different from those observed at T0 (23.5 ± 8.6 ng/mL) at T6mo. No difference between serum calcium levels was observed between the groups throughout the study. In conclusion, monthly supplementation with50,000UIofVTDinwinter canwarrant serum25(OH)Dlevels above 20ng/mL in96.2%of thosehealthy young adultswithout inducing unacceptably high 25(OH)D concentration. This supplementation is safe andmay be proposed without 25(OH)D testing. [less ▲]

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See detailQuelles dynamiques d'identification organisationnelle lors de processus de modernisation? Analyse d'une administration belge.
Rondeaux, Giseline ULg

in Revue Internationale des Sciences Administratives [= RISA] (in press), 80(mars),

Dans les diverses réformes conçues et implémentées en vue de moderniser l’administration, l’accent est mis sur les marchés avec un focus particulier sur les citoyens désormais clients (Korunka et al ... [more ▼]

Dans les diverses réformes conçues et implémentées en vue de moderniser l’administration, l’accent est mis sur les marchés avec un focus particulier sur les citoyens désormais clients (Korunka et al., 2007 ; Thomas, 2012). Alors que les approches initiales du NPM se centraient sur l’efficience, l’applicabilité et la pertinence de techniques managériales importées du secteur privé dans les organisations publiques (Ferlie et al., 1996), les réformes plus récentes tendent à inclure d’autres objectifs tels que la gestion de la qualité, la transparence et le centrage client (Meier & O’Toole, 2007 ; Lapsley, 2008). Du Gay (1996), pour sa part, affirme que le NPM est un projet identitaire, dans la mesure où il vise à redéfinir la main d’œuvre (en termes de profils et compétences recherchées, ciblant la figure du travailleur-entrepreneur en lieu et place du fonctionnaire). Bon nombre d’études interrogent également les paradoxes et les tensions intrinsèques du modèle NPM (Lynn, 1998; Aucoin, 1990; Hood, 2000 ; Goldfish & Wallis, 2010), les difficultés liées à sa mise en œuvre (Mathiasen, 1999 ; Dunleavy et al., 2006 ; Jones & Cole, 2009) ou à l’évaluation de ses outputs concrets pour l’administration (Pollitt, 1993; Hodge, 1999). De façon générale, la littérature met en lumière les effets que ces réformes ont produit sur les différentes facettes de l’administration : ses modes de fonctionnement et ses structures (Gualmini, 2008), son management, ses stratégie et pratiques de GRH (Pichault, 2007), ses missions et son identité organisationnelle (Horton, 2006) mais aussi sur l’ethos (Maesschalk, 2004 ; Fortier, 2010) et la motivation des fonctionnaires (Vandenabeele et Hondeghem, 2007), entre autres éléments. Plusieurs auteurs mentionnent les débats et questionnements identitaires qui se produisent lorsque l’organisation fait face à des situations de bouleversement profond (Albert et Whetten, 1985 ; Dutton et al., 1994 ; Alvesson et Empson, 2008). Dans un processus de réforme, l’organisation se remet en question et s’interroge sur ce qu’elle est, ce qu’elle devient, ce qu’elle veut être, propulsant l’identité organisationnelle au premier plan des préoccupations (Skalen, 2004 ; Meyer & Hammerschmid, 2006). Dans un contexte où l’identité organisationnelle est en proie à tel bouleversement, comment ses membres en font-ils l’expérience ? Ce questionnement, à la base de cet article, se pose en termes d’identification organisationnelle, unissant dans une même équation deux termes centraux : l’identité organisationnelle et les perceptions qu’ont les membres du contexte en évolution. La question que nous adressons est la suivante : dans un contexte d’organisation publique en mutation, quelles sont les dynamiques identitaires à l’oeuvre en regard de la perception des évolutions du contexte des individus ? A partir de l'analyse de la réforme Copernic (introduction du NPM dans l'administration fédérale belge) réalisée en 2005-2006, nous avons élaboré de manière inductive une typologie des logiques et profils identitaires, issue de l’analyse d’entretiens qualitatifs (Rondeaux, 2007, 2008, 2010). Sur base de celle-ci, nous avons mené une enquête par questionnaires auprès d’une administration régionale belge, engagée dans un processus de modernisation, en vue de vérifier l’existence et la pertinence de cette typologie, au moyen d’une démarche quantitative. Réalisée en 2010, cette enquête illustre en particulier trois aspects : 1. les représentations associées au travail au sein de l’administration en regard de son évolution, et le degré d’identification à l’institution dans ce contexte ; 2. la perception de la modernisation et le rôle de la hiérarchie dans cette perspective ; 3. les identités représentées au sein de l’institution (logiques institutionnalisée et alternatives, profils en congruence ou en dissonance). Nous montrons notamment que la majorité des positions est marquée par la dissonance, principalement relative à la valeur ajoutée de la modernisation et à sa mise en œuvre concrète. [less ▲]

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See detailPressure-impulse diagram of a beam under explosion - Influence of the indirectly affected part
Hamra, Lotfi ULg; Demonceau, Jean-François ULg; Denoël, Vincent ULg

in Eurosteel - 2014 (in press)

The paper studies the structural response of a beam subjected to a close-field local internal blast loading. In the literature, the pressure-impulse (p-I) diagram is commonly used to design elements or ... [more ▼]

The paper studies the structural response of a beam subjected to a close-field local internal blast loading. In the literature, the pressure-impulse (p-I) diagram is commonly used to design elements or structures for a given blast loading. The p-I diagram is a spectrum representing the level sets of damage or required ductility for a given structural system, nonlinear beam in this paper. This representation is much appreciated because a simple reading for the actual pressure p and impulse I of the considered load indicates the ductility demand of the structural system. Recent works of quasi-static behaviour have indicated the crucial need to account for the membrane effects taking place in the extreme loading of frame beams. This paper will thus extend the state-of-art features, establishing thus the p-I diagram for a beam including the lateral restraints offered by the rest of the structure, the development of non-linear membrane action and also, the M-N interaction that develops in the plastic hinges. [less ▲]

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See detailLa sécurité affective chez l'enfant en milieu résidentiel : Des soins du corps au bien être émotionnel
Aprile, Pauline ULg; Englebert, Jérôme ULg; Gauthier, Jean-Marie ULg

in Evolution Psychiatrique (in press)

Objectives - This review studies the concept of affective security in children living outside of their family environment by a brief exposition of its practical illustration in institution. We want to ... [more ▼]

Objectives - This review studies the concept of affective security in children living outside of their family environment by a brief exposition of its practical illustration in institution. We want to show that sufficient affective security can be achieved even in children institutionalized with major attachment difficulties. Method - We will first examine the original meaning of the concept by a theoretical review of its evolution over the years in the literature. Then, we will consider various questions concerning the legitimacy of institutionalization in link with affective security through a case analysis illustrating the issue. We will finally end by mentioning the main practical implications about the optimization of affective security in children institutionalized. Results - It is foremost by the predictable and expected daily acts posed by the professional caregivers in institution that the child may find sufficient affective security, generating emotional well-being and ultimately, an overall adequate development. Discussion – Children early separated from their family home to be placed in residential institution most often suffer from serious difficulties in terms of attachment to others. In this context, the institution has to deal with a specifically challenge: that is, to help the child to (re-)find sufficient internal security to allow him to grow on solid foundations. The institutional life which replaces family life primarily consists of an organizational structure that seeks to make child life as predictable as possible so that it has the necessary daily benchmarks to evolve adequately. Conclusion – In the everyday life in institution, the professionals struggling with children’s attachment disorders constantly try to achieve a right emotional-body balance through their psycho-educational practices with the child deprived of secure attachment strategies. [less ▲]

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