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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 detailInfluence of noise correction on intra- and inter-subject variability of quantitative metrics in diffusion kurtosis imaging
André, Elodie ULg; Grinberg, Farida; Farrher, Ezequiel et al

in PLoS ONE (in press)

Diffusion kurtosis imaging (DKI) is a promising extension of diffusion tensor imaging, giving new insights into the white matter microstructure and providing new biomarkers. Given the rapidly increasing ... [more ▼]

Diffusion kurtosis imaging (DKI) is a promising extension of diffusion tensor imaging, giving new insights into the white matter microstructure and providing new biomarkers. Given the rapidly increasing number of studies, DKI has a potential to establish itself as a valuable tool in brain diagnostics. However, to become a routine procedure, DKI still needs to be improved in terms of robustness, reliability, and reproducibility. As it requires acquisitions at higher diffusion31 weightings, results are more affected by noise than in diffusion tensor imaging. The lack of standard procedures for post-processing, especially for noise correction, might become a significant obstacle for the use of DKI in clinical routine limiting its application. We considered two noise correction schemes accounting for the noise properties of multichannel phased-array coils, in order to improve the data quality at signal-to-noise ratio (SNR) typical for DKI. The SNR dependence of estimated DKI metrics such as mean kurtosis (MK), mean diffusivity (MD) and fractional anisotropy (FA) is investigated for these noise correction approaches in Monte Carlo simulations and in in vivo human studies. The intra-subject reproducibility is investigated in a single subject study by varying the SNR level and SNR spatial distribution. Then the impact of the noise correction on inter-subject variability is evaluated in a homogeneous sample of 25 healthy volunteers. Results show a strong impact of noise correction on the MK estimate, while the estimation of FA and MD was affected to a lesser extent. Both intra- and inter-subject SNR related variability of the MK estimate is considerably reduced after correction for the noise bias, providing more accurate and reproducible measures. In this work, we have proposed a straightforward method that improves accuracy of DKI metrics. This should contribute to standardization of DKI applications in clinical studies and making valuable inferences in group analysis and longitudinal studies. [less ▲]

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See detailMulti-period vehicle loading with stochastic release dates
Arda, Yasemin ULg; Crama, Yves ULg; Kronus, David ULg et al

in EURO Journal on Transportation and Logistics (in press)

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be ... [more ▼]

This paper investigates a multi-period vehicle loading problem with stochastic information regarding the release dates of items to be transported. The deterministic version of the problem can be formulated as a large-scale set covering problem. Several heuristic algorithms are proposed to generate decision policies for the stochastic optimization model over a long rolling horizon. The resulting policies have been extensively tested on instances which display the main characteristics of the industrial case-study that motivated the research. The tests demonstrate the benefits of the multi-period stochastic model over simple myopic strategies. A simple and efficient heuristic is shown to deliver good policies and to be robust against errors in the estimation of the probability distribution of the release dates. [less ▲]

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See detailA Schur Complement Method for DAE Systems in Power System Dynamic Simulations
Aristidou, Petros ULg; Fabozzi, Davide; Van Cutsem, Thierry ULg

in Lecture Notes in Computational Science and Engineering (in press)

This paper proposes a Schur complement-based Domain Decomposition Method to accelerate the time-domain simulation of large, non-linear and stiff Differential and Algebraic Equation systems stemming from ... [more ▼]

This paper proposes a Schur complement-based Domain Decomposition Method to accelerate the time-domain simulation of large, non-linear and stiff Differential and Algebraic Equation systems stemming from power system dynamic studies. The proposed algorithm employs a star-shaped decomposition scheme and exploits the locality and sparsity of the system. The simulation is accelerated by the use of quasi-Newton schemes and parallel programming techniques. The proposed algorithm is implemented using the shared-memory parallel programming model and tested on a large-scale, realistic power system model showing significant speedup. [less ▲]

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See detailAlgorithmic and Computational Advances for Fast Power System Dynamic Simulations
Aristidou, Petros ULg; Van Cutsem, Thierry ULg

in Proceedings of the IEEE PES General Meeting (in press)

In this paper, some algorithmic and computational advances are presented for power system dynamic simulations. The heart is a Schur-complement-based solution algorithm, stemming from domain decomposition ... [more ▼]

In this paper, some algorithmic and computational advances are presented for power system dynamic simulations. The heart is a Schur-complement-based solution algorithm, stemming from domain decomposition methods, applied to the differential-algebraic equation model. This algorithm is then accelerated computationally, by employing parallel computing techniques, and numerically, by exploiting time-scale decomposition and localization. Models of a real medium-scale system and a realistic large-scale test system are used for the performance evaluation of the proposed methods. [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 detailScalar triplet flavored leptogenesis: a systematic approach
Aristizabal Sierra, Diego ULg; Dhen, Mikael; Hambye, Thomas

in Journal of Cosmology and Astroparticle Physics [= JCAP] (in press)

Type-II seesaw is a simple scenario in which Majorana neutrino masses are generated by the exchange of a heavy scalar electroweak triplet. When endowed with additional heavy fields, such as right-handed ... [more ▼]

Type-II seesaw is a simple scenario in which Majorana neutrino masses are generated by the exchange of a heavy scalar electroweak triplet. When endowed with additional heavy fields, such as right-handed neutrinos or extra triplets, it also provides a compelling framework for baryogenesis via leptogenesis. We derive in this context the full network of Boltzmann equations for studying leptogenesis in the flavored regime. To this end we determine the relations which hold among the chemical potentials of the various particle species in the thermal bath. This takes into account the standard model Yukawa interactions of both leptons and quarks as well as sphaleron processes which, depending on the temperature, may be classified as faster or slower than the Universe Hubble expansion. We find that when leptogenesis is enabled by the presence of an extra triplet, lepton flavor effects allow the production of the B-L asymmetry through lepton number conserving CP asymmetries. This scenario becomes dominant as soon as the triplets couple more to leptons than to standard model scalar doublets. In this case, the way the B-L asymmetry is created through flavor effects is novel: instead of invoking the effect of L-violating inverse decays faster than the Hubble rate, it involves the effect of L-violating inverse decays slower than the Hubble rate. We also analyze the more general situation where lepton number violating CP asymmetries are present and actively participate in the generation of the B-L asymmetry, pointing out that as long as L-violating triplet decays are still in thermal equilibrium when the triplet gauge scattering processes decouple, flavor effects can be striking, allowing to avoid all washout suppression effects from seesaw interactions. In this case the amount of B-L asymmetry produced is limited only by a universal gauge suppression effect, which nevertheless goes away for large triplet decay rates. [less ▲]

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See detailCloistered Baryogenesis
Aristizabal Sierra, Diego ULg; Fong, Chee Sheng; Nardi, Enrico et al

in Journal of Cosmology and Astroparticle Physics [= JCAP] (in press)

The cosmological matter-antimatter asymmetry can arise from the baryon number conserving CP asymmetry in two body decays of heavy particles, when the two final states carry equal and opposite baryon ... [more ▼]

The cosmological matter-antimatter asymmetry can arise from the baryon number conserving CP asymmetry in two body decays of heavy particles, when the two final states carry equal and opposite baryon number, and one couples directly or indirectly to electroweak sphalerons so that its baryon asymmetry gets partly reprocessed into a lepton asymmetry, while the other remains chemically decoupled from the thermal bath with its baryon content frozen. After sphaleron switchoff the decay of the decoupled particles inject in the thermal plasma an unbalanced baryon asymmetry, giving rise to baryogenesis. We highlight the features of this mechanism in a type-I seesaw model extended by adding a new colored scalar coupled to the heavy Majorana neutrinos. If the colored scalar has an O(TeV) mass, it would leave at the LHC a characteristic signature throughout all layers of the detectors. [less ▲]

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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 detailLes arabismes dans le TLF : tentative de classement historique
Baiwir, Esther ULg

in Revue de Linguistique Romane (in press), 78

Parmi les nombreux mots traditionnellement étiquetés comme «arabismes» figurent des cas relevant de classes diverses. Nous jetons ici un regard diachronique et global sur cette classe de lexèmes ... [more ▼]

Parmi les nombreux mots traditionnellement étiquetés comme «arabismes» figurent des cas relevant de classes diverses. Nous jetons ici un regard diachronique et global sur cette classe de lexèmes particuliers, parmi lesquels nous distinguons les emprunts dits directs, émanant de contacts récurrents et prolongés entre populations arabophones et populations francophones, et les emprunts dits indirects, qu'en toute rigueur nous devrions exclure de notre étude en vertu de la défiance légitime envers l'etimologia remota. Nous tentons cependant de montrer que cette méfiance mérite d'être nuancée à l'aune des conclusions que cette pratique lexicographique permet de tirer sur les mouvements socio-historiques qu'elle illustre. En effet, de l'examen des itinéraires et des époques d'emprunt se dégage l'histoire des relations entre monde arabophone et monde roman. [less ▲]

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See detailRôle et langue de Tchantchès dans les représentations en castelets des romans de chevalerie : le cas des Quatre fils Aymon
Baiwir, Esther ULg; Impe, Anaëlle

in Enquêtes du Musée de la Vie Wallonne (in press)

Pourquoi et dans quelle mesure les montreurs de marionnettes liégeoises font-ils intervenir Tchantchès aux côtés des grands chevaliers médiévaux, dont les aventures constituent une part importante du ... [more ▼]

Pourquoi et dans quelle mesure les montreurs de marionnettes liégeoises font-ils intervenir Tchantchès aux côtés des grands chevaliers médiévaux, dont les aventures constituent une part importante du répertoire liégeois ? Quels sont ses moyens d'action, mais également ses modes d'expression ? Divers registres de langue apparaissent au fil des spectacles ; quels sont ceux prêtés à notre héros ? Et surtout, ce rôle et cette langue ont-ils évolué au fil du temps ? C’est à ces quelques questions que nous tentons de répondre, en observant les différentes interventions de Tchantchès dans les réécritures des aventures des quatre fils Aymon, l’une des œuvres les plus anciennes et les plus fréquemment jouées dans les théâtres liégeois dévolus aux comédiens de bois. [less ▲]

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See detailCarte géologique de Wallonie (Belgique) 1/10.000, 59/4 Nassogne
Barchy, Laurent; Dejonghe, Léon; Marion, Jean-Marc ULg

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000 based on a new field work and using previous scientific data, produced since the previous edition published in 1900 (Stainer)

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See detailCarte géologique de Wallonie (Belgique) 1/10.000. 59/3 Rochefort
Barchy, Laurent; Dejonghe, Léon; Marion, Jean-Marc ULg

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data, produced since the previous edition published in 1900 (Stainier)

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See detailCarte géologique de Wallonie (Belgique) 1/10.000, 48/7 Modave
Barchy, Laurent; Marion, Jean-Marc ULg

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New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous edition in 1902 (at 1/40.000, by Lohest, Forir ... [more ▼]

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous edition in 1902 (at 1/40.000, by Lohest, Forir and Mourlon). [less ▲]

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See detailCarte géologique de Wallonie (Belgique) 1/10.000, 48/8 Clavier
Barchy, Laurent; Marion, Jean-Marc ULg

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous edition in 1902 (at 1/40.000, by Lohest, Forir ... [more ▼]

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous edition in 1902 (at 1/40.000, by Lohest, Forir and Mourlon). [less ▲]

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See detailCarte géologique de Wallonie (Belgique) 1/10.000. 34/7 Visé
Barchy, Laurent; Marion, Jean-Marc ULg

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous editions in 1896 (at 1/40.000, by Forir)

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See detailcarte géologique de Wallonie (Belgique) 1/10.000. 34/8 Voeren
Barchy, Laurent; Marion, Jean-Marc ULg

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced since the previous edition in 1896 (at 1/40.000, by Forir).

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See detailCarte géologique de Wallonie (Belgique) 1/10.000. 54/7 Aye
Barchy, Laurent; Marion, Jean-Marc ULg

Cartographic material (in press)

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced, since the previous editions published in 1885 (Dupont et Purves ... [more ▼]

New geological map of Wallonia published at the scale of 1/25.000, based on a new field work and using previous scientific data produced, since the previous editions published in 1885 (Dupont et Purves) et 1902 (Lohest et Forir) [less ▲]

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