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See detail50 ans d'exploration de la planète Mars
Stiepen, Arnaud ULg

Conference given outside the academic context (2016)

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See detailCoeur de crèche
Courtejoie, Fabienne ULg

in A+ Architecture en Belgique (2016), 258

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See detailMapping of riparian invasive species with supervised classification of Unmanned Aerial System (UAS) imagery
Michez, Adrien ULg; Piégay, Hervé; Lisein, Jonathan ULg et al

in International Journal of Applied Earth Observation and Geoinformation (2016), 44

Riparian zones are key landscape features, representing the interface between terrestrial and aquatic ecosystems. Although they have been influenced by human activities for centuries, their degradation ... [more ▼]

Riparian zones are key landscape features, representing the interface between terrestrial and aquatic ecosystems. Although they have been influenced by human activities for centuries, their degradation has increased during the 20th century. Concomitant with (or as consequences of) these disturbances, the invasion of exotic species has increased throughout the world’s riparian zones. In our study, we propose a easily reproducible methodological framework to map three riparian invasive taxa using Unmanned Aerial Systems (UAS) imagery: Impatiens glandulifera Royle, Heracleum mantegazzianum Sommier and Levier, and Japanese knotweed (Fallopia sachalinensis (F. Schmidt Petrop.), Fallopia japonica (Houtt.) and hybrids). Based on visible and near-infrared UAS orthophoto, we derived simple spectral and texture image metrics computed at various scales of image segmentation (10,30, 45, 60 using eCognition software). Supervised classification based on the random forests algorithm was used to identify the most relevant variable (or combination of variables) derived from UAS imagery for mapping riparian invasive plant species. The models were built using 20% of the dataset, the rest of the dataset being used as a test set (80%). Except for H. mantegazzianum, the best results in terms of global accuracy were achieved with the finest scale of analysis (segmentation scale parameter = 10). The best values of overall accuracies reached 72%, 68%, and 97% for I. glandulifera, Japanese knotweed, and H. mantegazzianum respectively. In terms of selected metrics, simple spectral metrics (layer mean / camera brightness) were the most used. Our results also confirm the added value of texture metrics (GLCM derivatives) for mapping riparian invasive species. The results obtained for I. glandulifera and Japanese knotweed do not reach sufficient accuracies for operational applications. However, the results achieved for H. mantegazzianum are encouraging. The high accuracies values combined to relatively light model-inputs needed (delineation of a few umbels) make our approach a serious contender as a cost-effective tool to improve the field management of H. mantegazzianum. [less ▲]

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See detailCharacterization of GPR101 transcripts structure, expression and signaling
Trivellin, G; Bjelobaba, I; Daly, Adrian ULg et al

in Abstract book - Keystone Symposia on GPCRs (2016, February)

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See detailDoing better in more complex patients: leading the way for QUIP.
Osnabrugge, Ruben L.; Kappetein, A. Pieter; Head, Stuart J. et al

in European journal of cardio-thoracic surgery : official journal of the European Association for Cardio-thoracic Surgery (2016), 49(2), 397-8

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See detailGeschichtsvereine und Geschichtsbewusstsein in der DG (2. Teil)
Brüll, Christoph ULg

Article for general public (2016)

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See detailUse of carbon - chlorine dual isotope analysis to assess the degradation pathways of 1,1,1-trichloroethane in groundwater
Palau, Jordi; Jamin, Pierre ULg; Badin, Alice et al

in Water Research (2016)

Compound-specific isotope analysis (CSIA) is a powerful tool to track contaminant fate in groundwater. However, the application of CSIA to chlorinated ethanes has received little attention so far. These ... [more ▼]

Compound-specific isotope analysis (CSIA) is a powerful tool to track contaminant fate in groundwater. However, the application of CSIA to chlorinated ethanes has received little attention so far. These compounds are toxic and prevalent groundwater contaminants of environmental concern. The high susceptibility of chlorinated ethanes like 1,1,1-trichloroethane (1,1,1-TCA) to be transformed via different competing pathways (biotic and abiotic) complicates the assessment of their fate in the subsurface. In this study, the use of a dual C-Cl isotope approach to identify the active degradation pathways of 1,1,1-TCA is evaluated for the first time in an aerobic aquifer impacted by 1,1,1-TCA and trichloroethylene (TCE) with concentrations of up to 20 mg/L and 3.4 mg/L, respectively. The reaction-specific dual carbon-chlorine (C-Cl) isotope trends determined in a recent laboratory study illustrated the potential of a dual isotope approach to identify contaminant degradation pathways of 1,1,1-TCA. Compared to the dual isotope slopes (Δδ13C/Δδ37Cl) previously determined in the laboratory for dehydrohalogenation / hydrolysis (DH/HY, 0.33 ± 0.04) and oxidation by persulfate (∞), the slope determined from field samples (0.6 ± 0.2, r2 = 0.75) is closer to the one observed for DH/HY, pointing to DH/HY as the predominant degradation pathway of 1,1,1-TCA in the aquifer. The observed deviation could be explained by a minor contribution of additional degradation processes. This result, along with the little degradation of TCE determined from isotope measurements, confirmed that 1,1,1-TCA is the main source of the 1,1-dichlorethylene (1,1-DCE) detected in the aquifer with concentrations of up to 10 mg/L. This study demonstrates that a dual C-Cl isotope approach can strongly improve the qualitative and quantitative assessment of 1,1,1-TCA degradation processes in the field. [less ▲]

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See detailLINKING CATTLE GRAZING BEHAVIOR TO METHANE AND CARBON DIOXIDE DYNAMICS
Blaise, Yannick ULg; Lebeau, Frédéric ULg; Andriamandroso, Andriamasinoro ULg et al

in Communications in Agricultural and Applied Biological Sciences (2016, February), 81(1), 107-112

Various methods are presently used to measure methane (CH4) emissions of ruminants on pasture. Those measurements are essential to evaluate nutritional strategies to mitigate enteric CH4 emissions as well ... [more ▼]

Various methods are presently used to measure methane (CH4) emissions of ruminants on pasture. Those measurements are essential to evaluate nutritional strategies to mitigate enteric CH4 emissions as well as addressing the selection of low producing individuals. On pasture and in the barn, variations in CH4 emissions are observed depending on the time of the day. However, no studies have been made to link these diurnal fluctuations to behavioural phases, especially on pasture. The aim of this study was to understand the individual dynamics of CH4 production and their links to the grazing behaviour. For this purpose, a new tool was specifically developed. Five red-pied dry cows were equipped with infrared CH4 and carbon dioxide (CO2) sensors measuring concentrations in the exhaled air at 4 Hz. The animals were equipped with a heart rate belt (HR) and motion sensors to detect their feeding behaviours (grazing vs. rumination) for periods of 8 h/d. Wind speed (WS) was also monitor to verify interference with sampled gas concentrations. Results showed that using the CH4:CO2 ratio reduced the interference with WS that was observed on raw CH4 and CO2 concentration signals. CH4:CO2 ratio average over 5 min periods indicated that CH4 emissions were lower during grazing than rumination (P<0.01). The eructation frequency during grazing (0.48 eructation/min, P<0.01) was also lower than during rumination (0.65 eructation/min). HR was higher during grazing that rumination. Because HR is usually linked to metabolic CO2 production intensity, hence influencing the denominator of the CH4:CO2 ratio, further investigation should focus on the quantification of changes in fermentative and metabolic CO2 emissions along the day to estimate total CH4 production more accurately and the relationship between CH4 emissions patterns and post-feeding times. [less ▲]

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See detailL'arrêt de mort des (trop) petites circonscriptions électorales wallonnes
Bouhon, Frédéric ULg

in Journal des Tribunaux (2016), 6634

Cet article propose un commentaire de l'arrêt n° 169/2015 de la Cour constitutionnelle belge, par lequel elle a considéré que les règles législatives qui instaurent les plus petites circonscriptions ... [more ▼]

Cet article propose un commentaire de l'arrêt n° 169/2015 de la Cour constitutionnelle belge, par lequel elle a considéré que les règles législatives qui instaurent les plus petites circonscriptions utilisées pour les élections du Parlement wallon sont inconstitutionnelles. L'article revient sur les enjeux du découpage du territoire en circonscriptions électorales, sur la jurisprudence antérieure en la matière et suggère un certain nombre d'adaptations que le législateur wallon pourrait adopter pour réagir à l'arrêt. [less ▲]

See detailEmergency department bed coordination: burden and pitfalls.
GILLET, Aline ULg; Minder, Anaïs ULg; Nyssen, Anne-Sophie ULg et al

Conference (2016, January 30)

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See detailUn laboratoire d'auto-immunité paperless: mythe ou réalité?
LUTTERI, Laurence ULg

Conference (2016, January 29)

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See detailOne day walk
Gantois, Gisele ULg

Scientific conference (2016, January 29)

One day walk Within my research I’m trying to find methods and tools to trace, unveil and map social & ecological values of built heritage in rural areas. In this contribution I’d like to discuss one of ... [more ▼]

One day walk Within my research I’m trying to find methods and tools to trace, unveil and map social & ecological values of built heritage in rural areas. In this contribution I’d like to discuss one of the methods I developed namely ‘A protocol for walking.’ The approach focuses on thinking through walking and drawing rather than an attempt to directly resolve or structure a problem. It aims at triggering curiosity not necessarily resulting in a solution or a conclusion while following a non-linear path. Walking acts like a starting trigger to investigate the cultural landscape and aims at generating and facilitating a thought process. It is therefore a way of reflecting. While walking, the act of watching closely can lead to real closeness and might help to gain insight into people’s and other living creatures attitudes, value system, concerns, motivations, aspirations, culture and behaviours and their interaction with space. As one needs the sharp eye to discover even the most trusted things, the act of drawing while walking becomes a way of observing. The drawing turns into a tool for the eye and makes one seeing things differently. The essential concept in this methodology is to approach the problem in an indirect way by postponing the problem. This is a way of tackling the uncertainty of the ‘ill-defined’ nature of the problem statement as values and significances cannot easily or clearly be defined. [less ▲]

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See detailCo-simulation of Electromagnetic Transients and Phasor Models of Electric Power Systems
Plumier, Frédéric ULg

Doctoral thesis (2016)

This study investigates and improves methods used for the combination of phasor and electromagnetic transients time domain simulations of power systems. It involves the study of the protocols of ... [more ▼]

This study investigates and improves methods used for the combination of phasor and electromagnetic transients time domain simulations of power systems. It involves the study of the protocols of computation, the comparison of the different kinds of boundary conditions used to represent one sub-system when simulating the other, and the interfacing of phasor and electromagnetic transients models. The Nordic system has been used to realize the tests. Illustrative simulation results are reported for the case of a single and of multiple boundary buses between the sub-systems. [less ▲]

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See detailData-driven selection of the minimum-gradient support parameter in time-lapse focused electrical imaging
Nguyen, Frédéric ULg; Kemna, Andreas; Robert, Tanguy et al

in Geophysics (2016), 81(1), 1-5

We have considered the problem of the choice of the minimum-gradient support (MGS) parameter in focused inversion for time-lapse (TL) electric resistivity tomography. Most existing approaches have relied ... [more ▼]

We have considered the problem of the choice of the minimum-gradient support (MGS) parameter in focused inversion for time-lapse (TL) electric resistivity tomography. Most existing approaches have relied either on an arbitrary choice of this parameter or one based on the prior information, such as the expected contrast in the TL image. We have decided to select the MGS parameter using a line search based on the value of the TL data root-mean-square misfit at the first iteration of the nonlinear inversion procedure. The latter was based on a Gauss-Newton scheme minimizing a regularized objective function in which the regularization functional was defined by the MGS functional. The regularization parameter was optimized to achieve a certain target level, following the Occam principles. We have validated our approach on a synthetic benchmark using a complex and heterogeneous model and determined its effectiveness on electric tomography TL data collected during a salt tracer experiment in fractured limestone. Our results have determined that the approach was successful in retrieving the focused anomaly and did not rely on prior information. [less ▲]

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See detailTwo cases of atypical CALR mutations in MPN patients
SAGOT, Clémence ULg; CHARLIER, Hélène ULg; KOOPMANSCH, Benjamin ULg et al

Poster (2016, January 29)

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See detailHolocene paleoenvironmental reconstructions from speleothem and peat bog archives
Allan, Mohammed ULg; VERHEYDEN; CRUCIFIX, Michel et al

Poster (2016, January 28)

The geological materials (speleothems and peatbogs) presented in Belgium (Hautes-Fagnes Plateau, Ardennes caves) are interesting archives for atmospheric pollution record and climate variability. Both ... [more ▼]

The geological materials (speleothems and peatbogs) presented in Belgium (Hautes-Fagnes Plateau, Ardennes caves) are interesting archives for atmospheric pollution record and climate variability. Both archives are easily dated (U/Th and counting for laminated speleothems, 210Pb and 14C for peatbogs), have a high temporal resolution (decadal to seasonal), contain multiple measurable parameters (elemental geochemistry, stable isotopes, radiogenic Nd and Pb isotopes, pollens, rates of peat humification, luminescence and thickness of laminated speleothems) and depending on environmental conditions of temperature and / or humidity. The aim of this study is to determine the sensitivity of both archives (speleothems and peatbogs) to human perturbations and climate changes. Our ultimate goal is to contribute to a better understanding of natural interglacial climate variability by generating and confronting high resolution paleoclimate reconstructions from 2 continental archives. [less ▲]

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