Last 7 days     Results 2601-2620 of 61833.   126 127 128 129 130 131 132 133 134 135 136   Characterization of the high-albedo NEA 3691 BedeWooden, Diane H.; Lederer, Susan M.; Jehin, Emmanuel et alin AAS/Division for Planetary Sciences Meeting Abstracts (2016, October 01)Characterization of NEAs provides important inputs to models for atmospheric entry, risk assessment and mitigation. Diameter is a key parameter because diameter translates to kinetic energy in atmospheric ... [more ▼]Characterization of NEAs provides important inputs to models for atmospheric entry, risk assessment and mitigation. Diameter is a key parameter because diameter translates to kinetic energy in atmospheric entry. Diameters can be derived from the absolute magnitude, H(PA=0deg), and from thermal modeling of observed IR fluxes. For both methods, the albedo (pv) is important - high pv surfaces have cooler temperatures, larger diameters for a given Hmag, and shallower phase curves (larger slope parameter G). Thermal model parameters are coupled, however, so that a higher thermal inertia also results in a cooler surface temperature. Multiple parameters contribute to constraining the diameter.Observations made at multiple observing geometries can contribute to understanding the relationships between and potentially breaking some of the degeneracies between parameters. We present data and analyses on NEA 3691 Bede with the aim of best constraining the diameter and pv from a combination of thermal modeling and light curve analyses. We employ our UKIRT+Michelle mid-IR photometric observations of 3691 Bede's thermal emission at 2 phase angles (27&43 deg 2015-03-19 & 04-13), in addition to WISE data (33deg 2010-05-27, Mainzer+2011).Observing geometries differ by solar phase angles and by moderate changes in heliocentric distance (e.g., further distances produce somewhat cooler surface temperatures). With the NEATM model and for a constant IR beaming parameter (eta=constant), there is a family of solutions for (diameter, pv, G, eta) where G is the slope parameter from the H-G Relation. NEATM models employing Pravec+2012's choice of G=0.43, produce D=1.8 km and pv≈0.4, given that G=0.43 is assumed from studies of main belt asteroids (Warner+2009). We present an analysis of the light curve of 3691 Bede to constrain G from observations. We also investigate fitting thermophysical models (TPM, Rozitis+11) to constrain the coupled parameters of thermal inertia (Gamma) and surface roughness, which in turn affect diameter and pv. Surface composition can be related to pv. This study focuses on understanding and characterizing the dependency of parameters with the aim of constraining diameter, pv and thermal inertia for 3691 Bede. [less ▲]Detailed reference viewed: 8 (1 ULg) VLT/SPHERE observations and shape reconstruction of asteroid (6) HebeMarsset, Michael; Carry, Benoit; Dumas, Christophe et alin AAS/Division for Planetary Sciences Meeting Abstracts (2016, October 01)(6) Hebe is a large main-belt asteroid, accounting for about half a percent of the mass of the asteroid belt. Its spectral characteristics and close proximity to dynamical resonances within the main-belt ... [more ▼](6) Hebe is a large main-belt asteroid, accounting for about half a percent of the mass of the asteroid belt. Its spectral characteristics and close proximity to dynamical resonances within the main-belt (the 3:1 Kirkwood gap and the nu6 resonance) make it a probable parent body of the H-chondrites and IIE iron meteorites found on Earth.We present new AO images of Hebe obtained with the high-contrast imager SPHERE (Beuzit et al. 2008) as part of the science verification of the instrument. Hebe was observed close to its opposition date and throughout its rotation in order to derive its 3-D shape, and to allow a study of its surface craters. Our observations reveal impact zones that witness a severe collisional disruption for this asteroid. When combined to previous AO images and available lightcurves (both from the literature and from recent optical observations by our team), these new observations allow us to derive a reliable shape model using our KOALA algorithm (Carry et al. 2010). We further derive an estimate of Hebe's density based on its known astrometric mass. [less ▲]Detailed reference viewed: 18 (1 ULg) A large strain hyperelastic viscoelastic-viscoplastic-damage constitutive model based on a multi-mechanism non-local damage continuum for amorphous glassy polymersNguyen, Van Dung ; Lani, Frédéric; Pardoen, Thomas et alin International Journal of Solids and Structures (2016), 96A large strain hyperelastic phenomenological constitutive model is proposed to model the highly nonlinear, rate-dependent mechanical behavior of amorphous glassy polymers under isothermal conditions. A ... [more ▼]A large strain hyperelastic phenomenological constitutive model is proposed to model the highly nonlinear, rate-dependent mechanical behavior of amorphous glassy polymers under isothermal conditions. A corotational formulation is used through the total Lagrange formalism. At small strains, the viscoelastic behavior is captured using the generalized Maxwell model. At large strains beyond a viscoelastic limit characterized by a pressure-sensitive yield function, which is extended from the Drucker-Prager one, a viscoplastic region follows. The viscoplastic flow is governed by a non-associated Perzyna-type flow rule incorporating this pressure-sensitive yield function and a quadratic flow potential in order to capture the volumetric deformation during the plastic process. The stress reduction phenomena arising from the post-peak plateau and during the failure stage are considered in the context of a continuum damage mechanics approach. The post-peak softening is modeled by an internal scalar, so-called softening variable, whose evolution is governed by a saturation law. When the softening variable is saturated, the rehardening stage is naturally obtained since the isotropic and kinematic hardening phenomena are still developing. Beyond the onset of failure characterized by a pressure-sensitive failure criterion, the damage process leading to the total failure is controlled by a second internal scalar, so-called failure variable. The final failure occurs when the failure variable reaches its critical value. To avoid the loss of solution uniqueness when dealing with the continuum damage mechanics formalism, a non-local implicit gradient formulation is used for both the softening and failure variables, leading to a multi-mechanism non-local damage continuum. The pressure sensitivity considered in both the yield and failure conditions allows for the distinction under compression and tension loading conditions. It is shown through experimental comparisons that the proposed constitutive model has the ability to capture the complex behavior of amorphous glassy polymers, including their failure. [less ▲]Detailed reference viewed: 106 (56 ULg) Advancing the integration of corporate sustainability measurement, management and reportingMaas, Karen; Schaltegger, Stefan; Crutzen, Nathalie in Journal of Cleaner Production (2016), 133Detailed reference viewed: 64 (5 ULg) X-ray and optical spectroscopy of the massive young open cluster IC 1805Rauw, Grégor ; Nazé, Yaël in Astronomy and Astrophysics (2016), 594(A82), 19Context. Very young open clusters are ideal places to study the X-ray properties of a homogeneous population of early-type stars. In this respect, the IC 1805 open cluster is very interesting as it hosts ... [more ▼]Context. Very young open clusters are ideal places to study the X-ray properties of a homogeneous population of early-type stars. In this respect, the IC 1805 open cluster is very interesting as it hosts the O4 If+ star HD 15570 thought to be in an evolutionary stage intermediate between a normal O-star and a Wolf-Rayet star. Aims: Such a star could provide a test for theoretical models aiming at explaining the empirical scaling relation between the X-ray and bolometric luminosities of O-type stars. Methods: We have observed IC 1805 with XMM-Newton and further collected optical spectroscopy of some of the O-star members of the cluster. Results: The optical spectra allow us to revisit the orbital solutions of BD+60° 497 and HD 15558, and provide the first evidence of binarity for BD+60° 498. X-ray emission from colliding winds does not appear to play an important role among the O-stars of IC 1805. Notably, the X-ray fluxes do not vary significantly between archival X-ray observations and our XMM-Newton pointing. The very fast rotator BD+60° 513, and to a lesser extent the O4 If+ star HD 15570 appear somewhat underluminous. Whilst the underluminosity of HD 15570 is only marginally significant, its amplitude is found to be compatible with theoretical expectations based on its stellar and wind properties. A number of other X-ray sources are detected in the field, and the brightest objects, many of which are likely low-mass pre-main sequence stars, are analyzed in detail. [less ▲]Detailed reference viewed: 16 (4 ULg) Discovery of WASP-113b and WASP-114b, two inflated hot-Jupiters with contrasting densitiesBarros, S. C. C.; Brown, D. J. A.; Hébrard, G. et alin Astronomy and Astrophysics (2016), 593We present the discovery and characterisation of the exoplanets WASP-113b and WASP-114b by the WASP survey, {\it SOPHIE} and {\it CORALIE}. The planetary nature of the systems was established by ... [more ▼]We present the discovery and characterisation of the exoplanets WASP-113b and WASP-114b by the WASP survey, {\it SOPHIE} and {\it CORALIE}. The planetary nature of the systems was established by performing follow-up photometric and spectroscopic observations. The follow-up data were combined with the WASP-photometry and analysed with an MCMC code to obtain system parameters. The host stars WASP-113 and WASP-114 are very similar. They are both early G-type stars with an effective temperature of $\sim 5900\,$K, [Fe/H]$\sim 0.12$ and $T_{\rm eff}$ $\sim 4.1$dex. However, WASP-113 is older than WASP-114. Although the planetary companions have similar radii, WASP-114b is almost 4 times heavier than WASP-113b. WASP-113b has a mass of $0.48\,$ $\mathrm{M}_{\rm Jup}$ and an orbital period of $\sim 4.5\,$days; WASP-114b has a mass of $1.77\,$ $\mathrm{M}_{\rm Jup}$ and an orbital period of $\sim 1.5\,$days. Both planets have inflated radii, in particular WASP-113 with a radius anomaly of $\Re=0.35$. The high scale height of WASP-113b ($\sim 950$ km ) makes it a good target for follow-up atmospheric observations. [less ▲]Detailed reference viewed: 12 (2 ULg) Using PCB signatures and enantiomer fractions for source identification and to age date exposureMegson, D; Focant, Jean-François ; Patterson, D et alConference (2016, October)Detailed reference viewed: 30 (2 ULg) Microsampling and Screening Technologies for Human Biomonitoring of Selected Persistent Organic Pollutants (POPs)Calaprice, Chiara ; L'Homme, B; Focant, Jean-François Conference (2016, October)Detailed reference viewed: 25 (3 ULg) Dioxins! Hunting the Great White.Focant, Jean-François Scientific conference (2016, October)Detailed reference viewed: 28 (2 ULg) A Simple Method for Thermal Characterization of Low-Melting Temperature Phase Change Materials (PCMs)Salvador, Lucas ; Hastanin, Juriy ; Novello, Frédéric et alin COMSOL 2016 Proceedings (2016, October)The successful implementation of a high-efficient latent heat storage system necessitates an appropriate experimental approach to investigate and quantify the variations of the Phase Change Material (PCM ... [more ▼]The successful implementation of a high-efficient latent heat storage system necessitates an appropriate experimental approach to investigate and quantify the variations of the Phase Change Material (PCM) thermal properties caused by its aging, as well as its potential demixing induced by cyclic freezing and melting. In this paper, we present a concept for the PCM characterization. The proposed method is relatively simple to be implemented. It consists of a cyclic cooling and melting of the PCM sample placed into a tube and monitoring its temperature evolution with a set of temperature sensors. In our work, the temperature evolution of the sample, as well as its sensitivity to the thermal parameters have been numerically investigated using the COMSOL Multiphysics® software. [less ▲]Detailed reference viewed: 26 (2 ULg) Multimodal Connectivity-Based Parcellation of the BrainReuter, Niels; Plachti, Anna; Genon, Sarah et alPoster (2016, October)Detailed reference viewed: 29 (2 ULg) Projet BELCAM: télédétection des besoins et rendements des culturesWellens, Joost Speech/Talk (2016)Detailed reference viewed: 25 (8 ULg) Transmission Efficiency of Cucumber Mosaic Virus by Myzus persicae According to Virus Strain and Aphid Clone from ChinaBosquée, Emilie ; Yin, Ronling; Bragard, Claude et alin Asian Journal of Plant Pathology (2016)Background: Cucumber mosaic virus (CMV) is one of the most important viruses infecting vegetables in the fields throughout the world. Transmission efficiency of CMV could depend on the variability of ... [more ▼]Background: Cucumber mosaic virus (CMV) is one of the most important viruses infecting vegetables in the fields throughout the world. Transmission efficiency of CMV could depend on the variability of virus strain but also aphid vector species and/or clones. Materials and Methods: By sequence analysis, the coat protein gene of CMV strains from different regions revealed that the CMV isolates used for this study belong to the same group. Both CMV strains and Myzus persicae (Sulzer) aphid clones were investigated for their role in viral dispersion by reciprocal tests on Nicotiana tabacum (L.) using the same clone of Myzus persicae towards different CMV strains or using one CMV strain on different Myzus persicae clones. Results: Virus transmission efficiency was found to be significantly influenced by selected CMV strains (from 5-30% of transmission rate for identical aphid clone) and also by the selected aphid clones (variation from 15-70% of transmission rate for identical virus strain). Conclusion: The CMV transmission efficiency depends on the variability of virus strain but also aphid vector clones. Combining the variability of CMV transmission rates for both aphid and virus sides, the prediction and modeling of virus spreading seems to be difficult to organize and are closely dependent on the variability of each protagonist-aphid and virus. [less ▲]Detailed reference viewed: 70 (10 ULg) La philosophie de la conscience comme intertexte des Temps Modernes et de CritiqueFranck, Thomas in Slamti, Sad; Chakir, Bouchra (Eds.) L'Interculturel dans la littérature et les arts. Matière et manière intertextuelles (2016)Detailed reference viewed: 24 (6 ULg) A review of Silurian dispersed spore assemblages from the Arabian Plate: biostratigraphy and palaeogeographyWellman, CH; Steemans, Philippe ; Breuer, P et alConference (2016, October)Detailed reference viewed: 32 (4 ULg) Le bouleau, une essence qui s'impose. Description de la ressource dans son aire de distributionDubois, Héloïse ; Latte, Nicolas ; Lecomte, Hugues et alin FORÊT.NATURE (2016), 140L'essentiel de la ressource en bouleau (verruqueux et pubescent) se situe en Russie et en Scandinavie (15 milliards de m³) et cette ressource augmente graduellement depuis plusieurs années. Il y est ... [more ▼]L'essentiel de la ressource en bouleau (verruqueux et pubescent) se situe en Russie et en Scandinavie (15 milliards de m³) et cette ressource augmente graduellement depuis plusieurs années. Il y est fortement valorisé en sciage, déroulage et trituration. En Europe de l'Ouest, cette croissance s'observe aussi, même si seulement 1 % de la ressource s'y concentre (dû notamment à la plus grande diversité d'essences commerciales présentes). En Wallonie, les évolutions du contexte socio-économique et environnemental jouent en faveur d'une augmentation de la présence du bouleau (parcelles non reboisées, entretien insuffisant, mélanges spontanés...). Le bouleau représente souvent une belle opportunité pour les mélanges, une excellente essence d'accompagnement et une diversification de la production. Mais, sans une sylviculture adaptée, les grumes sont généralement de faible dimension et présentent de nombreux défauts. C'est le cas de l'essentiel de la ressource actuelle en Wallonie. Aujourd'hui, les besoins sont de mieux le connaître, notamment les opportunités de valorisation, et d'aboutir à des recommandations sylvicoles. Il ne s'agit donc pas de vouloir faire du bouleau à tout prix mais plutôt de tirer profit d'une étape transitoire de la succession forestière. [less ▲]Detailed reference viewed: 27 (8 ULg) Conjoint influence of mind-wandering and sleepiness on task performanceStawarczyk, David ; D'Argembeau, Arnaud in Journal of Experimental Psychology. Human Perception & Performance (2016), 42(10), 1587-15600Recent research suggests that sleepiness and mind-wandering—the experience of thoughts that are both stimulus-independent and task-unrelated—frequently co-occur and are both associated with poorer ... [more ▼]Recent research suggests that sleepiness and mind-wandering—the experience of thoughts that are both stimulus-independent and task-unrelated—frequently co-occur and are both associated with poorer cognitive functioning. Whether these two phenomena have distinguishable effects on task performance remains unknown, however. To investigate this question, we employed the online experience sampling of mind-wandering episodes and subjective sleepiness during a laboratory task (the Sustained Attention to Response Task; SART), and also assessed mind-wandering frequency and sleep-related disturbances in daily life using self-report questionnaires. The results revealed that the tendency to experience mind-wandering episodes during the SART and daily life was associated with higher levels of daytime sleepiness and sleep-related disturbances. Importantly, however, mind-wandering and sleepiness were independent predictors of SART performance at both the within- and between-individuals levels. These findings demonstrate that, although mind-wandering and sleepiness frequently co-occur, these two phenomena have distinguishable and additive effects on task performance. [less ▲]Detailed reference viewed: 206 (8 ULg) Potential for Composite Analysis in the Black SeaCapet, Arthur ; Mason, Evan; Troupin, Charles et alConference (2016, October)Detailed reference viewed: 22 (11 ULg) Quantitative Three-Dimensional Color Flow Echocardiography of Chronic Mitral Regurgitation: New Methods, New Perspectives, New Challengeszhou, x; vannan, m; LANCELLOTTI, Patrizio in Journal of the American Society of Echocardiography (2016), 29(10), 935-937Detailed reference viewed: 9 (1 ULg) Analysis of the Nonlinear Dynamics of an F-16 Aircraft Using the NI2D ToolboxDetroux, Thibaut ; Dossogne, Tilàn ; Masset, Luc et alConference (2016, October)Detailed reference viewed: 20 (8 ULg)