Éditeur(s) : HAL CCSD
Résumé : International audience
Agrehtonmrwfsohptaeeleilmbxao.tfngioNcitfnhotsehwiaegtnchteoohdcnfyesststhaoaenrwlredsayepc.tstiaohcmcneodsoxots.pneilqIdgunei,fosfatnicms,htafoelnatysuppnsataccithmee-nlshzgiynteaotselhmwgosiesrwak,thenteelgritscoseogpxmaetcsephio-sroyevn:detsewoaimfnustonabrilqdkdcueueamcbsiaontugemtlbochittraeei.nssaWtzneehdlitoahmftbioehrnset. bsaTpTelrhgaeorsbcyv hintpi.choaerdmWsoetflhvaseclasrtetoohlubpeitesewtmahcpuoonlresso,twxceolienmaddstatitoechnldatedceimrtosiniegecnuposloiinstnsugchoaemincbrpgollandecxsurkticteb-bleachtoxaenuoc.snevFiatoelfrudtohtnheiolnserizxadefpslontfro,satahlpiuenotyoxmsinpnplagoocrseadittbyiooleniarmtsnipmspaolclizufezy,ttiiohhtnees. Trfhstoehlaueatiolcgnle.r iTtrhsmtep.larespnatsrtheotwrsmainolvegryaienwdothfemordesluintg.sOtenpocfnthleupsironblwem.prSescontdlhywpetraslpkeacbtiovuest I2fAnlSoawrdtT.eeleitrtoemdisriindveeo tnlheedgobpyytismaixnzoadtriboinmtaploropdcaeerslmaitentdgi rsesr[t1ne2t]pSleavtl=sw(ae;edic;o!mp o;sMe)awchnicdiaarteesospluetcitoinve
MIC Proceedings
Porto, Portugal

hal-00634751
https://hal.archives-ouvertes.fr/hal-00634751

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
OBJECTIVES:Blood rheology plays a key role in the pathophysiology of sickle cell anaemia (SS) and sickle cell haemoglobin C disease (SC), but its evolution over the lifespan is unknown.MATERIALS AND METHODS:Blood viscosity, red blood cell (RBC) deformability and aggregation, foetal haemoglobin (HbF) and haematocrit were measured in 114 healthy individuals (AA), 267 SS (161 children + 106 adults) and 138 SC (74 children + 64 adults) patients.RESULTS:Our results showed that 1) RBC deformability is at its maximal value during the early years of life in SS and SC populations, mainly because HbF level is also at its peak, 2) during childhood and adulthood, hydroxycarbamide treatment, HbF level and gender modulated RBC deformability in SS patients, independently of age, 3) blood viscosity is higher in older SS and SC patients compared to younger ones and 4) haematocrit decreases as SS patients age.CONCLUSION:The hemorheological changes detected in older patients could play a role in the progressive development of several chronic disorders in sickle cell disease, whose prevalence increases with age. Retarding these age-related haemorheological impairments, by using suitable drugs, may minimize the risks of vaso-occlusive events and chronic disorders.
ISSN: 1932-6203

Droits : http://creativecommons.org/licenses/by/
hal-01669747
https://hal.univ-antilles.fr/hal-01669747
DOI : 10.1371/journal.pone.0158182
PUBMED : 27355589
PUBMEDCENTRAL : PMC4927160

Éditeur(s) : HAL CCSD IRD
Résumé : International audience
The number of satellites and remote sensing sensors devoted to earth observation becomes increasingly high, providing more and more data and especially images. In the same time the access to such a data and to the tools to process them has been considerably improved. In the presence of such data flow - and regarding the necessity to follow up and predict environmental and societal changes in highly dynamic socio-environmental contexts - we need automatic image interpretation methods. This could be accomplished by exploring some strengths of artificial intelligence. Our main idea consists in inducing classification rules that explicitly take into account structural knowledge, using Aleph, an Inductive Logic Programming (ILP) system. We applied our proposed methodology to three land cover/use maps of the French Guiana littoral. One hundred and forty six classification rules were induced for the 39 land-cover classes of the maps. These rules are expressed in first order logic language which make them intelligible and interpretable by non-experts. A ten-fold cross validation gave average values for classification accuracy, specificity and sensibility equal to, respectively, 98.82 %, 99.65% and 70%. The proposed methodology could be valuably exploited to automatically classify new objects and/or help operators using object-based classification procedures.
Symposium of the Latin American Society for Remote Sensing and Spatial Information Systems (SELPER)
Cayenne, French Guiana

ird-00797337
http://hal.ird.fr/ird-00797337
http://hal.ird.fr/ird-00797337/document
http://hal.ird.fr/ird-00797337/file/Bayoudh_et_al_2012_FP_SELPER-086.pdf
IRD : fdi:010058343

Éditeur(s) : HAL CCSD
Résumé : International audience
The method we propose is a new approach to the problem of extbf{satellite constellation design}. The main difficulties of this field are the size of the solution space, the computation time of the optimization criterion and the lack of information to analyse and improve a solution. Our model bypasses some of these obstacles by using an extbf{inverse approach} where services to be fulfilled are highlighted. The algorithm is composed of different layers solving different problems. We first use the specifications of the services to compensate for lack of information returned by the criterion to analyse and improve a solution. An orbit database introduces an expert knowledge linked to a robust estimator to set consistent orbital parameters. We use a partial evaluation of the constellation to reduce the criterion computation time. The highest level of the algorithm is a metaheuristic layer that drives the search across the wide solution space with a probabilistic tabu search.
ICAI Proceeding

hal-00634752
https://hal.archives-ouvertes.fr/hal-00634752

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The number of satellites and sensors devoted to Earth observation has become increasingly elevated, delivering extensive data, especially images. At the same time, the access to such data and the tools needed to process them has considerably improved. In the presence of such data flow, we need automatic image interpretation methods, especially when it comes to the monitoring and prediction of environmental and societal changes in highly dynamic socio-environmental contexts. This could be accomplished via artificial intelligence. The concept described here relies on the induction of classification rules that explicitly take into account structural knowledge, using Aleph, an Inductive Logic Programming (ILP) system, combined with a multi-class classification procedure. This methodology was used to monitor changes in land cover/use of the French Guiana coastline. One hundred and fifty-eight classification rules were induced from 3 diachronic land cover/use maps including 38 classes. These rules were expressed in first order logic language, which makes them easily understandable by non-experts. A 10-fold cross-validation gave significant average values of 84.62%, 99.57% and 77.22% for classification accuracy, specificity and sensitivity, respectively. Our methodology could be beneficial to automatically classify new objects and to facilitate object-based classification procedures.
ISSN: 0098-3004

hal-01369822
https://hal.archives-ouvertes.fr/hal-01369822
https://hal.archives-ouvertes.fr/hal-01369822/document
https://hal.archives-ouvertes.fr/hal-01369822/file/CAGEO-D-13-00538R1_article.pdf
DOI : 10.1016/j.cageo.2014.08.013

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
BACKGROUND:Sickle cell anaemia (SCA) is a severe hereditary haemoglobinopathy characterised by haemorheological abnormalities, which play a role in the occurrence of several acute and chronic clinical complications. While βS -haplotypes and alpha-thalassaemia modulate SCA clinical severity, their effects on blood rheology have been incompletely described. The aim of this study was to test the effects of these genetic modifiers on the haemorheological properties and clinical complication of children with SCA.PROCEDURE:Steady-state haemorheological profile, biological parameters, βS -haplotypes, alpha-globin status, vaso-occlusive crisis (VOC) and acute chest syndrome frequencies were analysed in 128 children (aged 5 to 18 years) with SCA.RESULTS:Patients with alpha-thalassaemia showed increased red blood cell (RBC) deformability and aggregation compared to those without. Median VOC rate was higher in patients with homozygous alpha-thalassaemia compared to those with a normal alpha genotype. Conversely, the haemorheological profile and clinical complications were not influenced by the βS -haplotypes in our study.CONCLUSION:Our results demonstrate that alpha-thalassaemia is associated with higher risk for VOC events in children with SCA, which may be due in part to its effects on RBC deformability and aggregation.
ISSN: 1545-5009

hal-01668317
https://hal.univ-antilles.fr/hal-01668317
DOI : 10.1002/pbc.26455
PUBMED : 28097791

Éditeur(s) : HAL CCSD
Résumé : International audience
ThemethodweproseianewEa-pmaroila:chEtnoguheerpAaroBnb.SlGeTmrRaonAfdsCahtTealmitpe@ceonnsseteilhatt.firondesign.Themaindi culties saoenfrtvliycises atonldbaeimrfuptl hoevediazsroelfuhtihgnl.sgoOhlutterid
EURO

hal-00634753
https://hal.archives-ouvertes.fr/hal-00634753

Éditeur(s) : HAL CCSD
Résumé : International audience
Le nombre de satellites et de capteurs pour la télédétection dédiés à l'observation de la Terre ne cesse d'augmenter, permettant ainsi d'avoir une masse de données importante en particulier en matière d'images. Parallèlement, un effort permanent vise, d'une part, à améliorer l'accès à ces données et, d'autre part, à développer d'avantages d'outils pour les manipuler. De tels efforts sont particulièrement utiles dans des contextes socio-environnementaux très dynamiques spatialement et temporellement, pour lesquels il est nécessaire de suivre et de prédire les événements environnementaux et sociétaux. En revanche, en présence d'un tel flux de données, nous avons besoin de méthodes automatiques d'interprétation d'images. Une solution envisageable pour répondre à ce besoin est de bénéficier des atouts de l'intelligence artificielle pour l'obtention de cartes d'occupation du sol issues d'une classification des régions des images. Afin de contribuer à l'automatisation de la classification, nous proposons une méthode d'induction de règles interprétables par des non-experts et mettant en évidence, explicitement, des connaissances structurelles. Cette méthode s'appuie sur la programmation logique inductive (PLI) et en particulier sur le système inductif ”Aleph”. L'application de la méthode de classification Multi-class Rule Set Intersection (MRSI) permet ensuite de classifier tout nouvel objet au regard des ses caractéristiques intrinsèques et de celles des objets environnants. Nous avons appliqué notre méthodologie à l'étude de la dynamique du littoral de la Guyane Française. Suite à ce travail, nous avons induit 136 règles de classification pour 38 classes d'occupation du sol. Ces règles sont intelligibles et simples à interpréter de par l'utilisation de la logique du premier ordre. Les performances du système ont été évaluées par la validation croisée. En moyenne, la précision, la spécificité et la sensibilité sont, respectivement, égales à 84,62%, 99,57% et 77,22%. Ces résultats quantitatifs montrent une bonne performance de la méthodologie pour la mise à jour automatique de cartes d'occupation du sol et/ou l'assistance aux opérateurs utilisant l'analyse d'image orientée-objet.
11èmes Rencontres des Jeunes Chercheurs en Intelligence Artificielle
Lille, France

hal-01376400
https://hal.archives-ouvertes.fr/hal-01376400
https://hal.archives-ouvertes.fr/hal-01376400/document
https://hal.archives-ouvertes.fr/hal-01376400/file/Bayoudh_RJCIA2013.pdf

Éditeur(s) : HAL CCSD
Résumé : International audience
Half away between edge detection and object recognition this study aim to characterize singularities in order to guide this two phases. The caracterization is obtained with a generalization of the Lipschitz exponents .for complex structures. This new characterization is called " maxima chain " and integrates the notion of value and spatial repartition of the maxima. The maxima chains are obtained with a multiscale decomposition using a Diadic Discrete Wavelet Transform (DDWT). We use the maxima of the gradient image computed with the wavelet details. The local maxima detect the position of irregular structures (edges) in the image (Canny algorithm). Then we characterize each maxima using their evolution across the different scales. A classification is made using the maxima chains. We integrate the classification to eliminate unwanted maxima (from noise or other objects) to drive the search of closed contours. In fact, there is a totally different signature from one maxima to another depending on the parameters of the objects : nature, shape, size, gray scale, texture, ...
RFIA Proceedings
Toulouse, France

hal-00602265
https://hal.archives-ouvertes.fr/hal-00602265

Éditeur(s) : HAL CCSD
Résumé : International audience
Half away between edge detection and pattern recognition this study aim to characterize singularities in order to build closed edges and to classify object within an image.
IGARSS
Toulouse, France

hal-00602262
https://hal.archives-ouvertes.fr/hal-00602262