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See detailStagnation of Saturn's auroral emission at noon
Radioti, Aikaterini ULg; Grodent, Denis ULg; Gérard, Jean-Claude ULg et al

in Journal of Geophysical Research. Space Physics (2017)

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See detailPermutations and negative beta-shifts
Charlier, Emilie ULg; Steiner, Wolfgang

E-print/Working paper (2017)

Elizalde (2011) characterized which permutations can be obtained by ordering consecutive elements in the trajectories of (positive) beta-transformations and beta-shifts. We prove similar results for ... [more ▼]

Elizalde (2011) characterized which permutations can be obtained by ordering consecutive elements in the trajectories of (positive) beta-transformations and beta-shifts. We prove similar results for negative bases beta. [less ▲]

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See detailDevelopments in Language Theory
Charlier, Emilie ULg; Leroy, Julien ULg; Rigo, Michel ULg

Book published by Springer (2017)

The series of international conferences on Developments in Language Theory provides a forum for presenting current developments in formal languages and automata. Its scope is very general and includes ... [more ▼]

The series of international conferences on Developments in Language Theory provides a forum for presenting current developments in formal languages and automata. Its scope is very general and includes, among others, the following topics and areas: combinatorial and algebraic properties of words and languages; grammars, acceptors and transducers for strings, trees, graphs, arrays; algebraic theories for automata and languages; codes; efficient text algorithms; symbolic dynamics; decision problems; relationships to complexity theory and logic; picture description and analysis; polyominoes and bidimensional patterns; cryptography; concurrency; cellular automata; bio-inspired computing; quantum computing. The papers submitted to DLT 2017 were from 19 countries including Belgium, Canada, Czech Republic, France, Germany, Hungary, India, Italy, Japan, The Netherlands, Poland, Portugal, Republic of Korea, Russia, Slovakia, South Africa, Thailand and USA. [less ▲]

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See detailThe International Heat Stress Genotype Experiment for modeling wheat response to heat: field experiments and AgMIP-Wheat multi-model simulations.
Martre, P.; Reynolds, M. P.; Asseng, S. et al

in Open Data Journal for Agricultural Research (2017), 3

The data set contains a portion of the International Heat Stress Genotype Experiment (IHSGE) data used in the AgMIP-Wheat project to analyze the uncertainty of 30 wheat crop models and quantify the impact ... [more ▼]

The data set contains a portion of the International Heat Stress Genotype Experiment (IHSGE) data used in the AgMIP-Wheat project to analyze the uncertainty of 30 wheat crop models and quantify the impact of heat on global wheat yield productivity. It includes two spring wheat cultivars grown during two consecutive winter cropping cycles at hot, irrigated, and low latitude sites in Mexico (Ciudad Obregon and Tlaltizapan), Egypt (Aswan), India (Dharwar), the Sudan (Wad Medani), and Bangladesh (Dinajpur). Experiments in Mexico included normal (November-December) and late (January-March) sowing dates. Data include local daily weather data, soil characteristics and initial soil conditions, crop measurements (anthesis and maturity dates, anthesis and final total above ground biomass, final grain yields and yields components), and cultivar information. Simulations include both daily in-season and end-of-season results from 30 wheat models. [less ▲]

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See detailEvaluating the impact of soil conservation measures on soil organic carbon at the farm scale
Pezzuolo, Andrea; Dumont, Benjamin ULg; Sartori, Luigi et al

in Computers & Electronics in Agriculture (2017), 135

No-tillage (NT) is considered the least invasive conservation agriculture technique and has shown to be the effective in increasing soil C stocks, and reducing losses compared to others tillage systems ... [more ▼]

No-tillage (NT) is considered the least invasive conservation agriculture technique and has shown to be the effective in increasing soil C stocks, and reducing losses compared to others tillage systems. In Italy, the Veneto Region was the first to establish a subsidies scheme aimed at promoting the adoption of NT practices. This program encourages farmers to perform direct seeding, alternate autumn and winter crops and maintain soil cover throughout the year by leaving crop residues or sowing cover crops. The goals of this study were to: (i) compare the CO2 emission and soil C sequestration patterns of agricultural soils under CT and NT management practices in the Veneto region and (ii) analyse the potential mid-term benefits (2010–2025) of NT management in terms of soil organic C dynamics and CO2 balance. Agronomic data and soil organic carbon levels were measured from 2010 to 2014 in eight farms in the Veneto region that had adopted CT and NT techniques. Field measurements were used to calibrate first and then validate the SALUS model to compare the mid-term impact of CT and NT practices using climate projections. SOC carbon pools in the model were initialized using the procedure described in Basso et al. (2011c). This is the first study to employ a model using such an extensive dataset at the farm level to assess the CT and NT strategies within this region. Results of this research will assist farmers and policy makers in the region to define the tillage systems most suited to improve soil C stocks and thereby minimize CO2 emissions from agricultural soils. Overall, simulations indicated that SOC stocks can decrease under both CT and NT regimes, however SOC oxidation rates were substantially lower under NT. Critically, the greatest reduction in CO2 emission was observed when NT was adopted in soil with high levels of SOM. This highlights the benefits of NT adoption in terms of soil fertility preservation and CO2 emissions mitigation. [less ▲]

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See detailObservational signatures of past mass-exchange episodes in massive binaries: the case of LSS 3074
Raucq, Françoise ULg; Gosset, Eric ULg; Rauw, Grégor ULg et al

in Astronomy and Astrophysics (2017), 601

Context. The role of mass and momentum exchanges in close massive binaries is very important in the subsequent evolution of the components. Such exchanges produce several observational signatures such as ... [more ▼]

Context. The role of mass and momentum exchanges in close massive binaries is very important in the subsequent evolution of the components. Such exchanges produce several observational signatures such as asynchronous rotation and altered chemical compositions, that remain after the stars detach again. Aims. We investigated these effects for the close O-star binary LSS 3074 (O4 f + O6-7:(f):), which is a good candidate for a past Roche lobe overflow (RLOF) episode because of its very short orbital period, P = 2.185 days, and the luminosity classes of both components. Methods.We determined a new orbital solution for the system. We studied the photometric light curves to determine the inclination of the orbit and Roche lobe filling factors of both stars. Using phase-resolved spectroscopy, we performed the disentangling of the optical spectra of the two stars.We then analysed the reconstructed primary and secondary spectra with the CMFGEN model atmosphere code to determine stellar parameters, such as the effective temperatures and surface gravities, and to constrain the chemical composition of the components. Results. We confirm the apparent low stellar masses and radii reported in previous studies. We also find a strong overabundance in nitrogen and a strong carbon and oxygen depletion in both primary and secondary atmospheres, together with a strong enrichment in helium of the primary star. Conclusions. We propose several possible evolutionary pathways through a RLOF process to explain the current parameters of the system. We confirm that the system is apparently in overcontact configuration and has lost a significant portion of its mass to its surroundings. We suggest that some of the discrepancies between the spectroscopic and photometric properties of LSS 3074 could stem from the impact of a strong radiation pressure of the primary. [less ▲]

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See detailIncidence of MAGED2 on cell cycle after a camptothecin treatment
Trussart, Charlotte ULg; Pirlot, Céline; Piette, Jacques ULg et al

Poster (2017)

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See detailL’artiste, un commissaire idéal pour réactualiser le patrimoine muséal
Bawin, Julie ULg

in Chaumier, Serge (Ed.) PRATIQUES DE COMMISSARIAT D’EXPOSITION RÉCITS D’EXPÉRIENCES POUR UNE RÉFLEXION INCARNÉE (2017)

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See detailDamage prediction in single point incremental forming using an extended Gurson model
Guzman, Carlos Felipe; Yuan, Sibo ULg; Duchene, Laurent ULg et al

in International Journal of Solids and Structures (2017)

Single point incremental forming (SPIF) has several advantages over traditional forming, such as the high formability attainable by the material. Different hypotheses have been proposed to explain this ... [more ▼]

Single point incremental forming (SPIF) has several advantages over traditional forming, such as the high formability attainable by the material. Different hypotheses have been proposed to explain this behavior, but there is still no straightforward relation between the particular stress and strain state induced by SPIF and the material degradation leading to localization and fracture. A systematic review of the state of the art about formability and damage in SPIF is presented and an extended Gurson–Tvergaard–Needleman (GTN) model was applied to predict damage in SPIF through finite element (FE) simulations. The line test was used to validate the simulations by comparing force and shape predictions with experimental results. To analyze the failure prediction, several simulations of SPIF cones at different wall angles were performed. It is concluded that the GTN model underestimates the failure angle on SPIF due to wrong coalescence modeling. A physically-based Thomason coalescence criterion was then used leading to an improvement on the results by delaying the onset of coalescence. [less ▲]

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See detailNitric Oxide Nightglow and Martian Mesospheric Circulation from MAVEN/IUVS Observations and LMD-MGCM Predictions
Stiepen, Arnaud ULg; Jain; Schneider et al

in Journal of Geophysical Research. Space Physics (2017)

We report results from a study of nitric oxide nightglow over the north- ern hemisphere of Mars during winter, the southern hemisphere during fall equinox and equatorial latitudes during summer in the ... [more ▼]

We report results from a study of nitric oxide nightglow over the north- ern hemisphere of Mars during winter, the southern hemisphere during fall equinox and equatorial latitudes during summer in the northern hemisphere based on observations of the delta and gamma bands between 190 and 270 nm by the Imaging UltraViolet Spectrograph (IUVS) on the MAVEN spacecraft. The emission reveals recombination of N and O atoms dissociated on the day- side of Mars and transported to the nightside. We characterize the bright- ness (from 0.2 to 30 kR) and altitude (from 40 to 115 km) of the NO night- glow layer, as well as its topside scale height (mean of 11 km). We show the possible impact of atmospheric waves forcing longitudinal variability, asso- ciated with an increased brightness by a factor 3 in the 140 - 200 longitude region in the northern hemisphere winter and in the -102 to -48 longitude region at summer. Such impact to the NO nightglow at Mars was not seen before. Quantitative comparison with calculations of the LMD-MGCM (Lab- oratoire de M et eorologie Dynamique - Global Circulation Model) suggests that the model globally reproduces the trends of the NO nightglow emission and its seasonal variation, but also indicates large discrepancies (up to a fac- tor 50 fainter in the model) in northern winter at low to mid-latitudes. This suggests that the predicted transport is too e cient towards the night win- ter pole in the thermosphere by 20 latitude north. [less ▲]

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See detailDonnées nouvelles sur quelques espèces minérales de Vielsalm et Salmchâteau (Province de Luxembourg, Belgique)
Blondieau, M; Puccio, S; Compère, Philippe ULg et al

in Bulletin de la Société Royale des Sciences de Liège (2017), 86

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See detailNew Minerals, Nomenclature and Classification (CNMNC), Newsletter 36. New minerals and nomenclature modifications approved in 2016 and 2017
Halenius, U; Hatert, Frédéric ULg; Pasero, M et al

in European Journal of Mineralogy (2017), 29

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See detailRe-entrant inclusions in cellular solids: From defects to reinforcements
Zorzetto, Laura ULg; Ruffoni, Davide ULg

in Composite Structures (2017), 176

Abstract A contrast in Poisson ratio is a possible strategy to enhance the stiffness of composite structures. In solid materials Poisson ratio is hardly tailorable unless cellular architectures are ... [more ▼]

Abstract A contrast in Poisson ratio is a possible strategy to enhance the stiffness of composite structures. In solid materials Poisson ratio is hardly tailorable unless cellular architectures are considered. Here, we first investigated the effect of a single re-entrant inclusion acting as a defect into a regular (non-re-entrant) honeycomb lattice. Building on this, we generated regular patterns of re-entrant inclusions into a regular hexagonal cellular matrix and we characterized the apparent stiffness and Poisson ratio of the obtained structures. We also explored the role of the intrinsic material properties of the inclusion as well as of its closest environment on the interplay between the deformations of different phases in the lattice. Our main finding is that a small fraction of re-entrant inclusions (around 12%) is sufficient to generate a substantial augmentation in stiffness (300%) at constant overall relative density and without inducing strong anisotropy. Eventually, we fabricated by 3D polyjet printing bi-material composite architectures to demonstrate the superior mechanical behavior obtained exploiting the Poisson effect. [less ▲]

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See detailQuand la rue kinoise envahit le politique...
Polet, François ULg

in Cahiers Africains (2017), 94

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See detailAdaptation of Severity Factor Model According to the Operating Parameter Variations Which Occur During Steam Explosion Process
Jacquet, Nicolas ULg; Richel, Aurore ULg

in Thomsen, Hedegaard Mette; Trajano, Heather L.; Ruiz, Hector A. (Eds.) Hydrothermal Processing in Biorefineries Production of Bioethanol and High Added-Value Compounds of Second and Third Generation Biomass (2017)

Literature shows that steam explosion is a relevant process for the pretreatment of lignocellulosic biomass in the aims to improve the accessibility of materials by modification of their physicochemical ... [more ▼]

Literature shows that steam explosion is a relevant process for the pretreatment of lignocellulosic biomass in the aims to improve the accessibility of materials by modification of their physicochemical properties. All physicochemical modifications are functions of many parameters (pressure/temperature, retention time, pH, etc.) which are not constant and must be taken into account to estimate the pretreatment intensity. Previous paragraphs show that some models integrate the evolution of temperature/pressure and pH during the process. However, the biomass complexity indicates that many other parameters could be involved, which suggest that models developed today don’t give an accurate estimation of the treatment severity. To achieve a complete model, each parameter involved in the process should be further studied specifically to identify their effect on the process intensity. This approach would permit to know more precisely the effects of each parameter on the biomass structure and identify their impact on steam explosion intensity. [less ▲]

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