References of "Pirard, Eric"
     in
Bookmark and Share    
Full Text
Peer Reviewed
See detailSpreading segregation of blended fertilizers : influence of particles properties
Miserque, Olivier; Pirard, Eric ULg; Schenkel, Yves et al

in Applied Engineering in Agriculture (2008), 24(2), 137-144

Detailed reference viewed: 16 (1 ULg)
Full Text
Peer Reviewed
See detailMapping evaporitic minerals in Sud Lipez salt lakes (Bolivia) using remote sensing
Caceres, Fernando; Ali-Ammar, Hamid; Pirard, Eric ULg

in Reviews in Economic Geology (2008), 16

Detailed reference viewed: 64 (8 ULg)
Full Text
Peer Reviewed
See detailModal analysis of mineral blends using optical image analysis versus X ray diffraction
Bouzahzah, Hassan; Califice, Arnaud ULg; Benzaazoua, Mostafa et al

in GU, Ying; BUTCHER, Alan; STEELE, David (Eds.) Proceedings of International Congress for Applied Mineralogy ICAM08 (2008)

Detailed reference viewed: 143 (22 ULg)
Full Text
Peer Reviewed
See detailTechniques and applications for predictive metallurgy and ore
Lane, Geoff; Martin, Chris; Pirard, Eric ULg

in Minerals Engineering (2008), 21

Detailed reference viewed: 57 (7 ULg)
Peer Reviewed
See detailLandslide detection from remote sensing images using statistical and ANN classification methods
Danneels, Gaëlle; Havenith, Hans-Balder ULg; Pirard, Eric ULg

in Geophysical Research Abstracts (2007)

Detailed reference viewed: 6 (0 ULg)
Full Text
Peer Reviewed
See detailParticle texture analysis using polarized light imaging and grey level intercepts
Pirard, Eric ULg; Lebichot, Sophie; Krier, William

in International Journal of Mineral Processing (2007), 84(1-4), 299-309

The usual characterization of particulate ore material with image analysis includes modal analysis and liberation analysis. Both methods include stereological corrections based on intercept length ... [more ▼]

The usual characterization of particulate ore material with image analysis includes modal analysis and liberation analysis. Both methods include stereological corrections based on intercept length distributions within each phase of interest. The first principle of stereology relies on a simple assumption of uniform random sectioning, whereas the liberation models require all particles to have similar textural properties. However, for the sake of adequate prediction of ore behavior in industrial processes it is becoming more and more important to be able to describe particle populations in terms of texture classes. Among the texture analysis techniques, this paper focuses on mean intercept length (MIL). It brings two important improvements: the first one is to improve grain boundary imaging by using images of bireflectant minerals under plane polarized illumination, the second one is to consider intercept analysis on grey level images instead of binary ones. The method is illustrated on a selection of critical hematite textures found within banded iron formations. (C) 2007 Elsevier B.V. All rights reserved. [less ▲]

Detailed reference viewed: 143 (11 ULg)
Full Text
Peer Reviewed
See detailImpact of microbial activities on the mineralogy and performance of column-scale permeable reactive iron barriers operated under two different redox conditions
Van Nooten, Thomas; Lieben, François; Dries, Jan et al

in Environmental Science & Technology (2007), 41(16), 5724-5730

The present study focuses on the impact of microbial activities on the performance of various long-term operated laboratory-scale permeable reactive barriers. The barriers contained both aquifer and Fe-0 ... [more ▼]

The present study focuses on the impact of microbial activities on the performance of various long-term operated laboratory-scale permeable reactive barriers. The barriers contained both aquifer and Fe-0 compartments and had received either sulfate or iron(Ill)-EDTAto promote sulfatereducing and iron(Ill)-reducing bacteria, respectively. After dismantlement of the compartments after almost 3 years of operation, DNA-based PCR-DGGE analysis revealed the presence of methanogenic, sulfate-reducing, metalreducing, and denitrifying bacteria within as well as up- and downgradient of the Fe-0 matrix. Under all imposed conditions, the main secondary phases were vivianite, siderite, ferrous hydroxy carbonate, and carbonate green rust as found by scanning electron microscopy (SEM) combined with energy dispersive X-ray analysis (EDX), and X-ray diffraction (XRD). Under sulfate-reduction promoting conditions, iron sulfides were formed in addition, resulting in 7 and 10 times higher degradation rates for PCE and TICE, respectively, compared to unreacted iron. These results indicate that the presence of sulfate-reducing bacteria in or around iron barriers and the subsequent formation of iron sulfides might increase the barrier reactivity. [less ▲]

Detailed reference viewed: 56 (2 ULg)
Full Text
See detailSIZE DISTRIBUTION OF METALLIC POWDERS : A COMPARISON OF DIGITAL IMAGING AND LASER DIFFRACTION
Gregoire, Max; Michel, Frédéric ULg; Campana, Florent et al

Poster (2007)

Automated image analysis of particles under controlled orientation (SIA) is becoming a challenging technique for laser diffraction (LD) in the field of sizing metallic particles above 5 μm. Thanks to ... [more ▼]

Automated image analysis of particles under controlled orientation (SIA) is becoming a challenging technique for laser diffraction (LD) in the field of sizing metallic particles above 5 μm. Thanks to optimal particle dispersion and fully automated microscopic imaging, it is now possible to gather individual measurements on thousands of particles within a minute. The aim of this paper is to compare results obtained with both image analysis and laser diffraction from a selection of powders (figure 1) in the range between 5 μm and 250 μm. [less ▲]

Detailed reference viewed: 24 (1 ULg)
Full Text
See detailCaractérisation granulo-morphologique en 3D de poudres métalliques par micro-tomographie rayons-x
Gregoire, Max; Pirard, Eric ULg

in Dodds, J. A. (Ed.) Science & Technologie des Poudres - PMF 2007 (2007)

La morphologie des particules est une propriété essentielle pour comprendre et prédire leur rhéologie, leur agglomération, leur compaction et bien d'autres de leurs propriétés physiques. Suite à l ... [more ▼]

La morphologie des particules est une propriété essentielle pour comprendre et prédire leur rhéologie, leur agglomération, leur compaction et bien d'autres de leurs propriétés physiques. Suite à l'apparition de nouvelles techniques d'imagerie en trois dimensions adaptées aux matériaux, il est à présent possible d'étendre les descripteurs de forme existant en deux dimensions à la troisième. Deux échantillons de particules métalliques dont l'étendue granulaire est de 150-250 μm ont été selectionnés. Le choix de ces poudres est un véritable défi car la forme complexe des particules justifie l'élaboration de nouveaux descripteurs de taille et de forme. Cet article présentes les résultats de la caractérisation morphologique en trois dimensions de matériaux granulaires. L'acquisition d'images est pratiquée par microtomographie des rayons X permettant une résolution inférieure à 10 μm. Pour chaque particule, le volume, la surface, l'allongement, l'aplatissement, la convexité et le rayon de la sphère maximale inscrite sont calculés en trois dimensions. Les algorithmes écrits pour mesurer ces propriétés ont été validés sur des particules synthétiques. La réalisation d'une analyse morphologique complète de quelques milliers de particules permet d'appréhender les paramètres de forme de façon statistique. Finalement, les résultats seront confrontés à ceux obtenus par analyse d'image statique (SIA) en 2D. [less ▲]

Detailed reference viewed: 38 (1 ULg)
Full Text
Peer Reviewed
See detailAccuracy of size distributions obtained from single particle static digital image analysis.
Gregoire, Max; Dislaire, Godefroid; Pirard, Eric ULg

in Proceedings PARTEC2007 (2007)

Detailed reference viewed: 46 (7 ULg)
Full Text
Peer Reviewed
See detailAnalysis of landslide susceptibility in the Suusamyr region, Tien Shan: statistical and geotechnical approach
Havenith, Hans-Balder ULg; Strom, Alexander; Caceres, Fernando et al

in Landslides (2006), 3(1), 39-50

The Suusamyr region is located in the northern part of the Tien Shan Range in Central Asia. In 1992, this region was hit by the Ms = 7.3 Suusamyr earthquake triggering several large landslides along the ... [more ▼]

The Suusamyr region is located in the northern part of the Tien Shan Range in Central Asia. In 1992, this region was hit by the Ms = 7.3 Suusamyr earthquake triggering several large landslides along the Suusamyr Valley and on the southern slopes of the adjacent Suusamyr Range. One of these landslides had been investigated by geophysical and geotechnical methods in order to determine local trigger factors. The present paper focuses on the influence of geological and morphological factors upon landslide occurrence on a regional scale. The analysis is based on a digital data set including landslides triggered in 1992 and several older landslides as well as various types of digital elevation models (DEMs), ASTER image data, and geological and active fault maps. These data were combined to compute landslide susceptibility (LS) maps using statistical methods, Landslide Factor and Conditional Analyses (LFA, CA), as well as a geotechnical one, the Newmark's Method (NM). The landslide data set was also analyzed with respect to the size-frequency relationship. [less ▲]

Detailed reference viewed: 99 (6 ULg)
Peer Reviewed
See detailComputer Assisted Spore Classification based on Ornament Spatial Distribution Analysis – An Application to Emsian Miospores from Saudi Arabia
Dislaire, Godefroid; Breuer, Pierre; Filatoff, John et al

Conference (2006)

Detailed reference viewed: 49 (1 ULg)
Full Text
Peer Reviewed
See detailAdvanced particle characterization for improved; understanding of spray coating quality
Pirard, Eric ULg; Campana, Florent; Janssen, Jean-Pierre

in Proceedings International Thermal Spray Conference (2006)

The size and shape of individual particles are essential characteristics to control their behavior during spraying. Thanks to recently available technology in powder image analysis, this paper ... [more ▼]

The size and shape of individual particles are essential characteristics to control their behavior during spraying. Thanks to recently available technology in powder image analysis, this paper investigates the correlation between the geometric properties of several thousands of particles and their flowability (Hall flowmeter) and apparent density (Scott volumeter). Four different chromium carbide Cr3C2-NiCr 75/25 powders used for HVOF wear / oxidation resistant coatings are studied. The coating quality obtained for each powder by the HVOF spraying process is further investigated using metallographic image analysis. [less ▲]

Detailed reference viewed: 8 (1 ULg)
See detailLandslide risk analysis in the Mailuu-Suu valley (Kyrgyzstan) by means of remote sensing techniques
Danneels, Gaelle; Pirard, Eric ULg; Torgoev, Isakbek et al

in Geophysical Research Abstracts (2005)

Detailed reference viewed: 1 (0 ULg)
Full Text
Peer Reviewed
See detailImage processing of 2D resistivity data for imaging faults
Nguyen, Frédéric ULg; Garambois, Stephane; Jongmans, Denis et al

in Journal of Applied Geophysics (2005), 57(4), 260-277

A methodology to locate automatically limits or boundaries between different geological bodies in 2D electrical tomography is proposed, using a crest line extraction process in gradient images, This ... [more ▼]

A methodology to locate automatically limits or boundaries between different geological bodies in 2D electrical tomography is proposed, using a crest line extraction process in gradient images, This method is applied on several synthetic models and on field data set acquired on three experimental sites during the European project PALEOSIS where trenches were dug. The results presented in this work are valid for electrical tomographies data collected with a Wenner-alpha array and computed with an 1(1) norm (blocky inversion) as optimization method, For the synthetic cases. three geometric contexts are modelled: a vertical and a dipping fault juxtaposing two different geological formations and a step-like structure. A superficial layer can cover each geological structure. In these three situations, the method locates the synthetic faults and layer boundaries, and determines fault displacement but with several limitations. The estimated fault positions correlate exactly with the synthetic ones if a conductive (or no superficial) layer overlies the studied structure. When a resistive layer with a thickness of 6 in covers the model, faults are positioned with a maximum error of 1 m. Moreover, when a resistive and/or a thick top layer is present, the resolution significantly decreases for the fault displacement estimation (error up to 150%). The tests with the synthetic models for surveys using the Wenner-alpha array indicate that the proposed methodology is best suited to vertical and horizontal contacts. Application of the methodology to real data sets shows that a lateral resistivity contrast of 1:5 1:10 leads to exact faults location. A fault contact with a resistivity contrast of 1:0.75 and overlaid by a resistive layer with a thickness or 1 m gives an error location ranging from 1 to 3 m. Moreover, no result is obtained for a contact with very low contrasts (similar to 1:0.85) overlaid by a resistive soil. The method shows poor results when vertical gradients are greater than horizontal ones. This kind of image processing technique should be systematically used for improving the objectiveness of tomography interpretation when looking for limits between geological objects. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]

Detailed reference viewed: 171 (26 ULg)
See detailSpreading segregation of bulk blends
Miserque, Olivier; Pirard, Eric ULg; Schenkel, Yves

(2005)

Detailed reference viewed: 14 (3 ULg)
Full Text
See detailFertilizer particles characterization : standard methods and image analysis
Miserque, Olivier; Pirard, Eric ULg; Chapeau, Vincent

in Annual Meeting International Fine Particle Research Institute (2005)

Detailed reference viewed: 21 (0 ULg)
Full Text
Peer Reviewed
See detailGrey level intercepts distributions and grain size estimation
Lebichot, Sophie; Dislaire, Godefroid; Pirard, Eric ULg et al

in Proceedings 8th European Congress for Stereology and Image Analysis (2005)

Detailed reference viewed: 27 (5 ULg)