Browsing
     by title


0-9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

or enter first few letters:   
OK
Full Text
See detailCombining in vivo and in silico experiments to unravel root water uptake dynamics
Lobet, Guillaume ULg; Bhowmick, Suman; Couvreur, Valentin et al

Poster (2012)

Detailed reference viewed: 10 (0 ULg)
Full Text
Peer Reviewed
See detailCombining intercropping with semiochemical releases: optimization of alternative control of Sitobion avenae 1 in wheat crops in China
Wang, Guang; Cui, Liang-Liang; Dong, Jie et al

in Entomologia Experimentalis et Applicata (2011)

Detailed reference viewed: 25 (6 ULg)
Full Text
See detailCombining Ionosonde and GPS TEC Data to Assess NeQuick Formulation
Bidaine, Benoît ULg

Report (2008)

The main topic which was investigated during the mission is related to the validation of the NeQuick model using different data sets. The discussions were based on former work dealing with the comparison ... [more ▼]

The main topic which was investigated during the mission is related to the validation of the NeQuick model using different data sets. The discussions were based on former work dealing with the comparison of the first version of the model recommended by the ITU-R and its second version recently published. In addition the NeQuick formulation and its physical behaviour were discussed considering the bottomside and topside representations and the interaction between both. This will constitute the basis for future investigation of ingestion techniques using NeQuick as well as the ionospheric correction algorithm for Galileo single frequency users. [less ▲]

Detailed reference viewed: 124 (19 ULg)
Peer Reviewed
See detailCombining lazy learning, racing and subsampling for effective feature selection
Bontempi, Gianluca; Birattari, Mauro; Meyer, Patrick ULg

in Adaptive and Natural Computing Algorithms (2005)

Detailed reference viewed: 12 (0 ULg)
Full Text
See detailCombining magnetic and seismic studies to constrain processes in massive stars
Neiner, C.; Degroote, P.; Coste, B. et al

in IAUS 302 - Magnetic Fields Throughout Stellar Evolution (2014, August)

The presence of pulsations influences the local parameters at the surface of massive stars and thus it modifies the Zeeman magnetic signatures. Therefore it makes the characterisation of a magnetic field ... [more ▼]

The presence of pulsations influences the local parameters at the surface of massive stars and thus it modifies the Zeeman magnetic signatures. Therefore it makes the characterisation of a magnetic field in pulsating stars more difficult and the characterisation of pulsations is thus required for the study of magnetic massive stars. Conversely, the presence of a magnetic field can inhibit differential rotation and mixing in massive stars and thus provides important constraints for seismic modelling based on pulsation studies. As a consequence, it is necessary to combine spectropolarimetric and seismic studies for all massive classical pulsators. Below we show examples of such combined studies and the interplay between physical processes. [less ▲]

Detailed reference viewed: 25 (0 ULg)
Full Text
Peer Reviewed
See detailCombining mesoporosity and Ti-doping in hematite films for water splitting
Toussaint, Caroline ULg; Tran, Hoang Son ULg; Colson, Pierre ULg et al

in Journal of Physical Chemistry C (2015), 119(4), 1642-1650

(Graph Presented). In this study, we report the synthesis of Ti-doped mesoporous hematite films by soft-templating for application as photoanodes in the photoelectrolysis of water (water splitting ... [more ▼]

(Graph Presented). In this study, we report the synthesis of Ti-doped mesoporous hematite films by soft-templating for application as photoanodes in the photoelectrolysis of water (water splitting). Because the activation of the dopant requires a heat treatment at high temperature (≥800°C), it usually results in the collapse of the mesostructure. We have overcome this obstacle by using a temporary SiO2 scaffold to hinder crystallite growth and thereby maintain the mesoporosity. The beneficial effect of the activated dopant has been confirmed by comparing the photocurrent of doped and undoped films treated at different temperatures. The role of the mesostructure was investigated by comparing dense, collapsed, and mesoporous films heated at different temperatures and characterized under front and back illumination. It turns out that the preservation of the mesotructure enables a better penetration of the electrolyte into the film and therefore reduces the distance that the photogenerated holes have to travel to reach the electrolyte. As a result, we found that mesoporous films with dopant activation at 850°C perform better than comparable dense and collapsed films. [less ▲]

Detailed reference viewed: 44 (8 ULg)
Full Text
Peer Reviewed
See detailCombining microsatellite and pedigree data to estimate relationships among Skyros ponies.
Bömcke, Elisabeth ULg; Gengler, Nicolas ULg

in Journal of Applied Genetics (2009), 50(2), 133-43

Relationship coefficients are particularly useful to improve genetic management of endangered populations. These coefficients are traditionally based on pedigree data, but in case of incomplete or ... [more ▼]

Relationship coefficients are particularly useful to improve genetic management of endangered populations. These coefficients are traditionally based on pedigree data, but in case of incomplete or inexistent pedigrees they are replaced by coefficients calculated from molecular data. The main objective of this study was to develop a new method to estimate relationship coefficients by combining molecular with pedigree data, which is useful for specific situations where neither pedigree nor molecular data are complete. The developed method was applied to contribute to the conservation of the Skyros pony breed, which consists of less than 200 individuals, divided into 3 main herds or subpopulations. In this study, relationships between individuals were estimated using traditional estimators as well as the newly developed method. For this purpose, 99 Skyros ponies were genotyped at 16 microsatellite loci. It appeared that the limitation of the most common molecular-based estimators is the use of weights that assume relationships equal to 0. The results showed that, as a consequence of this limitation, negative relationship values can be obtained in small inbred populations, for example. By contrast, the combined estimator gave no negative values. Using principal component analysis, the combined estimator also enabled a better graphic differentiation between the 3 subpopulations defined previously. In conclusion, this new estimator can be a promising alternative to traditionally used estimators, especially in inbred populations, with both incomplete pedigree and molecular information. [less ▲]

Detailed reference viewed: 45 (7 ULg)
Full Text
Peer Reviewed
See detailCombining mindfulness and ACT to learn how to manage emotions and to engage in valued activities: Assessment of the feasibility of a training group and its efficiency
Wagener, Aurélie ULg; Dierickx, Christophe; Blairy, Sylvie ULg

Poster (2015, July 18)

BACKGROUND Managing painful emotions could be an issue for a lot of adults. Indeed, learning how to manage painful emotions is an often-requested demand in psychotherapy. Mindfulness-based programs and ... [more ▼]

BACKGROUND Managing painful emotions could be an issue for a lot of adults. Indeed, learning how to manage painful emotions is an often-requested demand in psychotherapy. Mindfulness-based programs and acceptance and commitment therapy (ACT) offer useful tools which aim to guide in this learning process. ACT also provide guidelines to engage in valued activities. In order to help community adults to manage their painful emotions and to engage themselves in valued activities, we offer training group cycles combining tools of mindfulness-based programs and ACT. This study aims to assess the feasibility of such training groups and their efficiency. METHODS A longitudinal design with three assessment-times (T0, T1 and T2) is employed. Participants to the training group attend to three three-hours training sessions on a six-weeks period. They are assessed before the training sessions (T0), directly after (T1) and at three-months follow-up (T2). Questionnaires assess these variables: sociodemographic data, mood, mindfulness, psychological flexibility, cognitive coping strategies and behavioural activation. Student t tests for paired samples are conducted. RESULTS Fifty-four adults participated to four training cycles (the cycles are all identical). Until now, 28 participants (21 women) completed the T0 and the T1 (mean age = 41.43, SD = 11.83). Student t test indicate a significant decrease of depression (t(25) = 4.53, p < 0,001), anxiety (t(25) = 6.23, p < 0.001) and non-adaptive cognitive coping strategies (t(24) = 3.76, p < 0.001). Student t test also indicate a significant increase in mindfulness (t(26) = -3.87, p < 0.001), psychological flexibility (t(26)) = -5.48, p < 0.001) and behavioural activation (t(26) = -4.86, p < 0.001). DISCUSSION Preliminary results indicate the feasibility of training groups combining tools of mindfulness-based programs and ACT. Results show a decrease in several variables (depression, anxiety and non-adaptive cognitive coping strategies) and an increase in other variables (mindfulness, psychological flexibility and behavioural activation). These results seem to indicate that participants benefit from the training groups. Data collection is still ongoing and a control group (waiting-list) is currently being composed. Results and clinical implications will be further discussed during the congress. [less ▲]

Detailed reference viewed: 28 (0 ULg)
Full Text
Peer Reviewed
See detailCombining Mixed Integer Programming and Supervised Learning for Fast Re-planning
Rachelson, Emmanuel ULg; Ben Abbes, Ala; Diemer, Sébastien

in Proceedings of the 22nd IEEE International Conference on Tools with Artificial Intelligence (2010)

We introduce a new plan repair method for problems cast as Mixed Integer Programs. In order to tackle the inherent complexity of these NP-hard problems, our approach relies on the use of Supervised ... [more ▼]

We introduce a new plan repair method for problems cast as Mixed Integer Programs. In order to tackle the inherent complexity of these NP-hard problems, our approach relies on the use of Supervised Learning method for the offline construction of a predictor which takes the problem’s parameters as input and infers values for the discrete optimization variables. This way, the online resolution time of the plan repair problem can be greatly decreased by avoiding a large part of the combinatorial search among discrete variables. This contribution was motivated by the large-scale problem of intra-daily recourse strategy computation in electrical power systems. We report and discuss results on this benchmark, illustrating the different aspects and mechanisms of this new approach which provided close-to-optimal solutions in only a fraction of the computational time necessary for existing solvers. [less ▲]

Detailed reference viewed: 15 (2 ULg)
Full Text
Peer Reviewed
See detailCombining Non-stably Infinite, Non-first Order Theories
Fontaine, Pascal; Gribomont, Pascal ULg

in Electronic Notes in Theoretical Computer Science (2005), 125(3), 37-51

Detailed reference viewed: 17 (6 ULg)
Full Text
Peer Reviewed
See detailCombining numerous uncorrelated MEMS gyroscopes for accuracy improvement based on an optimal Kalman filter
Chang, Honglong; Xue, Liang; Jiang, Chengyu et al

in IEEE Transactions on Instrumentation and Measurement (2012), 61(11), 3084--3093

In this paper, an approach to improve the accuracy of microelectromechanical systems (MEMS) gyroscopes by combining numerous uncorrelated gyroscopes is presented. A Kalman filter (KF) is used to fuse the ... [more ▼]

In this paper, an approach to improve the accuracy of microelectromechanical systems (MEMS) gyroscopes by combining numerous uncorrelated gyroscopes is presented. A Kalman filter (KF) is used to fuse the output signals of several uncorrelated sensors. The relationship between the KF bandwidth and the angular rate input is quantitatively analyzed. A linear model is developed to choose suitable system parameters for a dynamic application of the concept. Simulation and experimental tests of a six-gyroscope array proved that the presented approach was effective to improve the MEMS gyroscope accuracy. The experimental results indicate that six identical gyroscopes with a noise density of 0.11°/s/$\surd$Hz and a bias instability of 62°/h can be combined to form a virtual gyroscope with a noise density of 0.03°/s/$\surd$Hz and a bias instability of 16.8°/h . The accuracy improvement is better than that of a simple averaging process of the individual sensors. [less ▲]

Detailed reference viewed: 13 (0 ULg)
Full Text
Peer Reviewed
See detailCombining PET images and neuropsychological test data for automatic diagnosis of Alzheimer’s disease
Segovia-Román, Fermín ULg; Bastin, Christine ULg; Salmon, Eric ULg et al

in PLoS ONE (2014), 9(2),

In recent years, several approaches to develop computer aided diagnosis (CAD) systems for dementia have been proposed. Some of these systems analyze neurological brain images by means of machine learning ... [more ▼]

In recent years, several approaches to develop computer aided diagnosis (CAD) systems for dementia have been proposed. Some of these systems analyze neurological brain images by means of machine learning algorithms in order to find the patterns that characterize the disorder, and a few combine several imaging modalities to improve the diagnostic accuracy. However, they usually do not use neuropsychological testing data in that analysis. The purpose of this work is to measure the advantages of using not only neuroimages as data source in CAD systems for dementia but also neuropsychological scores. To this aim, we compared the accuracy rates achieved by systems that use neuropsychological scores beside the imaging data in the classification step and systems that use only one of these data sources. In order to address the small sample size problem and facilitate the data combination, a dimensionality reduction step (implemented using three different algorithms) was also applied on the imaging data. After each image is summarized in a reduced set of image features, the data sources were combined and classified using three different data combination approaches and a Support Vector Machine classifier. That way, by testing different dimensionality reduction methods and several data combination approaches, we aim not only highlighting the advantages of using neuropsychological scores in the classification, but also implementing the most accurate computer system for early dementia detention. The accuracy of the CAD systems were estimated using a database with records from 46 subjects, diagnosed with MCI or AD. A peak accuracy rate of 89% was obtained. In all cases the accuracy achieved using both, neuropsychological scores and imaging data, was substantially higher than the one obtained using only the imaging data. [less ▲]

Detailed reference viewed: 117 (13 ULg)
Full Text
Peer Reviewed
See detailCombining problem structure and basis reduction to solve a class of hard integer programs
Louveaux, Quentin ULg; Wolsey, Laurence A.

in Mathematics of Operations Research (2002), 27(3), 470-484

We consider a hard integer programming problem that is difficult for the standard branch-and-bound approach even for small instances. A reformulation based on lattice basis reduction is known to be more ... [more ▼]

We consider a hard integer programming problem that is difficult for the standard branch-and-bound approach even for small instances. A reformulation based on lattice basis reduction is known to be more effective. However the step to compute the reduced basis, even if it is found in polynomial time, becomes a bottleneck for small to medium instances. By using the structure of the problem, we show that we can decompose the problem and obtain the basis by taking the kronecker product of two smaller bases easier to compute. Furthermore, if the two small bases are reduced, the kronecker product is also reduced up to a reordering of the vectors. Computational results show the gain from such an approach. [less ▲]

Detailed reference viewed: 63 (15 ULg)
Full Text
Peer Reviewed
See detailCombining proteomics and metabolite analyses to unravel cadmium stress-response in poplar leaves
Kieffer, Pol ULg; Planchon, Sébastien; Oufir, Mouhssin et al

in Journal of Proteome Research (2009), 8

Detailed reference viewed: 99 (9 ULg)
Peer Reviewed
See detailCombining radiology and ultrasound for the assessment of the equine fetlock.
Busoni, Valeria ULg; Snaps, Frédéric ULg

in Proceedings EAVDI Meeting (2001)

Detailed reference viewed: 18 (4 ULg)
Full Text
See detailCombining remote sensing and ancillary data to improve species distribution models
Delangre, Jessica ULg; Radoux, Julien; Jacquemin, Floriane ULg et al

Poster (2015, May 21)

Correlative distribution models are increasingly used in biological conservation. They often require the compilation of various environmental attributes (climate, topography, land cover,…), which can be ... [more ▼]

Correlative distribution models are increasingly used in biological conservation. They often require the compilation of various environmental attributes (climate, topography, land cover,…), which can be very time-consuming. In the Lifewatch project, a database combining segmentation in homogeneous landscape units (“ecotopes”) and environmental attributes derived from regularly updated remote sensing data (land cover, potential solar energy,…) and other data sources (climate, topography,…) has been designed. Our aim was to assess the usefulness of this database for species distribution modelling and to propose further improvements. The distribution of ten species (four butterflies, three birds, two reptiles and one mammal) was modelled across Wallonia and model performance was assessed by Area Under the ROC Curve using the subsample approach. The models derived from ecotope segmentation and quantitative land cover attributes were compared to those obtained with a corresponding grid and a qualitative land cover database. The usefulness of ancillary data (soil properties, contextual attributes) was assessed to decide which variables should be integrated in the ecotope database. The results allowed us to assess and improve the relevance and accuracy of our database, which is a promising tool for species distribution modellers at the European scale. [less ▲]

Detailed reference viewed: 40 (3 ULg)
Full Text
Peer Reviewed
See detailCombining remote sensing imagery of both fine and coarse spatial resolution to estimate crop evapotranspiration and quantifying its influence on crop growth monitoring
Sepulcre-Canto, Guadalupe; Gellens-Meulenberghs, Françoise; Arboleda, Alirio et al

in Geophysical Research Abstracts (2010)

This study has been carried out in the framework of the GLOBAM -Global Agricultural Monitoring system by integration of earth observation and modeling techniques- project whose objective is to fill the ... [more ▼]

This study has been carried out in the framework of the GLOBAM -Global Agricultural Monitoring system by integration of earth observation and modeling techniques- project whose objective is to fill the methodological gap between the state of the art of local crop monitoring and the operational requirements of the global monitoring system programs. To achieve this goal, the research aims to develop an integrated approach using remote sensing and crop growth modeling. This paper concerns the use of MSG geostationnary satellite data for the calculation of Actual Evapotranspiration and its integration into a crop growth model. [less ▲]

Detailed reference viewed: 52 (1 ULg)
Full Text
Peer Reviewed
See detailCombining satellite, aerial and ground measurements to assess forest carbon stocks in Democratic Republic of Congo
Beaumont, Benoît; Bouvy, Alban; Stephenne, Nathalie et al

in Geophysical Research Abstracts, Vol. 17, EGU2015-4765-2, 2015 (2015)

Monitoring tropical forest carbon stocks changes has been a rising topic in the recent years as a result of REDD+ mechanisms negotiations. Such monitoring will be mandatory for each country willing to ... [more ▼]

Monitoring tropical forest carbon stocks changes has been a rising topic in the recent years as a result of REDD+ mechanisms negotiations. Such monitoring will be mandatory for each country willing to benefit from these financial incentives in the future. Aerial and satellite remote sensing technologies offer cost advantages in implementing large scale forest inventories. Despite the recent progress made in the use of airborne LiDAR for C stocks estimation, no widely operational and cost effective method has yet been delivered for central Africa forest monitoring. Within the Maï Ndombe region of DRC, the EO4REDD project develops a method combining satellite, aerial and ground measurements. This combination is done in three steps: [1] mapping and quantifying forest cover changes using an object-based semi-automatic change detection (deforestation and forest degradation) methodology based on very high resolution satellite imagery (RapidEye), [2] developing an allometric linear model for above ground biomass measurements based on dendrometric parameters (tree crown areas and heights) extracted from airborne stereoscopic image pairs and calibrated using ground measurements of individual trees on a data set of 18 one hectare plots and [3] relating these two products to assess carbon stocks changes at a regional scale. Given the high accuracies obtained in [1] (> 80% for deforestation and 77% for forest degradation) and the suitable, but still to be improved with a larger calibrating sample, model (R2 of 0.7) obtained in [2], EO4REDD products can be seen as a valid and replicable option for carbon stocks monitoring in tropical forests. Further improvements are planned to strengthen the cost effectiveness value/REDD+ suitability in the 2nd phase of EO4REDD. This 2nd phase will include [A] specific model developments per forest type; [B] measurements of afforestation, reforestation and natural regeneration processes and [C] study of Sentinel data series potential use. [less ▲]

Detailed reference viewed: 106 (2 ULg)