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A stacked dense denoising–segmentation network for undersampled tomograms and knowledge transfer using synthetic tomograms / Dimitrios Bellos in Machine Vision and Applications, vol 32 n° 3 (May 2021)  

Public [article]  inMachine Vision and Applications > vol 32 n° 3 (May 2021) . - n° 75 Titre : A stacked dense denoising–segmentation network for undersampled tomograms and knowledge transfer using synthetic tomograms Type de document : Article/Communication Auteurs : Dimitrios Bellos, Auteur ; Mark Basham, Auteur ; Tony Pridmore, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 75 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image [Termes IGN] acquisition de connaissances [Termes IGN] apprentissage profond [Termes IGN] échantillonnage [Termes IGN] filtrage du bruit [Termes IGN] rapport signal sur bruit [Termes IGN] rayon X [Termes IGN] reconstruction d'image [Termes IGN] segmentation sémantique [Termes IGN] série temporelle [Termes IGN] tomographie Résumé : (auteur) Over recent years, many approaches have been proposed for the denoising or semantic segmentation of X-ray computed tomography (CT) scans. In most cases, high-quality CT reconstructions are used; however, such reconstructions are not always available. When the X-ray exposure time has to be limited, undersampled tomograms (in terms of their component projections) are attained. This low number of projections offers low-quality reconstructions that are difficult to segment. Here, we consider CT time-series (i.e. 4D data), where the limited time for capturing fast-occurring temporal events results in the time-series tomograms being necessarily undersampled. Fortunately, in these collections, it is common practice to obtain representative highly sampled tomograms before or after the time-critical portion of the experiment. In this paper, we propose an end-to-end network that can learn to denoise and segment the time-series’ undersampled CTs, by training with the earlier highly sampled representative CTs. Our single network can offer two desired outputs while only training once, with the denoised output improving the accuracy of the final segmentation. Our method is able to outperform state-of-the-art methods in the task of semantic segmentation and offer comparable results in regard to denoising. Additionally, we propose a knowledge transfer scheme using synthetic tomograms. This not only allows accurate segmentation and denoising using less real-world data, but also increases segmentation accuracy. Finally, we make our datasets, as well as the code, publicly available. Numéro de notice : A2021-456 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1007/s00138-021-01196-4 Date de publication en ligne : 27/04/2021 En ligne : https://doi.org/10.1007/s00138-021-01196-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97902 [article]

Bayesian iterative reconstruction methods for 3D X-ray Computed Tomography / Camille Chapdelaine (2019)  

Public Titre : Bayesian iterative reconstruction methods for 3D X-ray Computed Tomography Type de document : Thèse/HDR Auteurs : Camille Chapdelaine, Auteur ; Charles Soussen, Directeur de thèse Editeur : Paris-Orsay : Université de Paris 11 Paris-Sud Centre d'Orsay Année de publication : 2019 Importance : 185 p. Format : 21 x 30 cm Note générale : Bibliographie Thèse de Doctorat de l’Université Paris - Saclay préparée à l'Université Paris-Sud, Sciences et Technologies de l’Information et de la Communication (STIC), Traitement du signal et des images Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image [Termes IGN] artefact [Termes IGN] faisceau [Termes IGN] inférence [Termes IGN] itération [Termes IGN] processeur graphique [Termes IGN] rayon X [Termes IGN] reconstruction 3D [Termes IGN] reconstruction d'image [Termes IGN] segmentation [Termes IGN] spectroscopie [Termes IGN] théorème de Bayes [Termes IGN] tomographie [Termes IGN] volume (grandeur) Index. décimale : THESE Thèses et HDR Résumé : (auteur) In industry, 3D X-ray Computed Tomography aims at virtually imaging a volume in order to inspect its interior. The virtual volume is obtained thanks to a reconstruction algorithm based on projections of X-rays sent through the industrial part to inspect. In order to compensate uncertainties in the projections such as scattering or beam-hardening, which are cause of many artifacts in conventional filtered backprojection methods, iterative reconstruction methods bring further information by enforcing a prior model on the volume to reconstruct, and actually enhance the reconstruction quality. In this context, this thesis proposes new iterative reconstruction methods for the inspection of aeronautical parts made by SAFRAN group. In order to alleviate the computational cost due to repeated projection and backprojection operations which model the acquisition process, iterative reconstruction methods can take benefit from the use of high-parallel computing on Graphical Processor Unit (GPU). In this thesis, the implementation on GPU of several pairs of projector and backprojector is detailed. In particular, a new GPU implementation of the matched Separable Footprint pair is proposed. Since many of SAFRAN's industrial parts are piecewise-constant volumes, a Gauss-Markov-Potts prior model is introduced, from which a joint reconstruction and segmentation algorithm is derived. This algorithm is based on a Bayesian approach which enables to explain the role of each parameter. The actual polychromacy of X-rays, which is responsible for scattering and beam-hardening, is taken into account by proposing an error-splitting forward model. Combined with Gauss-Markov-Potts prior on the volume, this new forward model is experimentally shown to bring more accuracy and robustness. At last, the estimation of the uncertainties on the reconstruction is investigated by variational Bayesian approach. In order to have a reasonable computation time, it is highlighted that the use of a matched pair of projector and backprojector is necessary. Note de contenu : 1- X-ray computed tomography : an inverse problem 2- Reconstruction methods in X-ray computed tomography 3- Projection and backprojection operators 4- Gauss-Markov-Potts prior model for joint reconstruction and segmentation 5- Error-splitting forward model and its application with Gauss-Markov-Potts prior 6- Towards the estimation of the uncertainties on the reconstruction by Variational Bayesian Approach 7- Conclusion and perspectives Numéro de notice : 25702 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Sciences et Technologies de l’Information et de la Communication (STIC) : Traitement du signal et des images : Paris 11 : 2019 Organisme de stage : Safran nature-HAL : Thèse DOI : sans En ligne : https://tel.archives-ouvertes.fr/tel-02110033 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94827

X-ray microdensitometry of wood: A review of existing principles and devices / Philippe Jacquin in Dendrochronologia, vol 42 (March 2017)  

Public [article]  inDendrochronologia > vol 42 (March 2017) . - pp 42 - 50 Titre : X-ray microdensitometry of wood: A review of existing principles and devices Type de document : Article/Communication Auteurs : Philippe Jacquin, Auteur ; Fleur Longuetaud, Auteur ; Jean-Michel Leban , Auteur ; Frédéric Mothe, Auteur Année de publication : 2017 Projets : ARBRE / AgroParisTech (2007 -) Article en page(s) : pp 42 - 50 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation [Termes IGN] dendrochronologie [Termes IGN] densité du bois [Termes IGN] rayon X [Termes IGN] tomographie Résumé : (auteur) Wood microdensitometry is the analysis of radial variations of density at the annual or intra-annual growth ring level. Density is related to wood quality, biomass, carbon content, tree growth and climate. Wood microdensitometry is particularly used in dendrochronology and climatology studies. The present study focuses on X-ray based methods used in wood microdensitometry analyses and provides a review of the main available devices. An exhaustive review of 75 works published on this topic in 2014 and 2015 showed that film-based equipment is still commonly used. The three other most popular devices, SilviScan, Itrax and QTRS, are also based on X-ray radiography and deliver results with comparable accuracy, below 50 μm per pixel. X-ray tomography (CT) is still rarely used in wood densitometry. Medical CT scanners currently offer a lower accuracy (above 100 μm per pixel) that is insufficient in most cases for ring or intra-ring scales. Micro-CT scanners offer good performance at the cost of much longer acquisition and reconstruction times. Numéro de notice : A2017-893 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.dendro.2017.01.004 Date de publication en ligne : 27/01/2017 En ligne : https://doi.org/10.1016/j.dendro.2017.01.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91887 [article]

Measuring wood density by means of X-ray computer tomography / Charline Freyburger in Annals of Forest Science, Vol 66 n° 8 (December 2009)  

Public [article]  inAnnals of Forest Science > Vol 66 n° 8 (December 2009) . - n° 804 Titre : Measuring wood density by means of X-ray computer tomography Titre original : Mesure de la densité du bois par tomographie à rayons X Type de document : Article/Communication Auteurs : Charline Freyburger, Auteur ; Fleur Longuetaud, Auteur ; Frédéric Mothe, Auteur ; Thiéry Constant, Auteur ; Jean-Michel Leban , Auteur Année de publication : 2009 Article en page(s) : n° 804 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation [Termes IGN] biomasse [Termes IGN] densité du bois [Termes IGN] étalonnage d'instrument [Termes IGN] puits de carbone [Termes IGN] rayon X [Termes IGN] tomographie Résumé : (Auteur) Wood density is a characteristic of major interest. Usually, it is used as an indicator of wood quality; however, in the context of global change, it is increasingly used for biomass and carbon storage estimations. X-ray computer tomography is a method which enables quick estimates of wood density after applying a calibration procedure. A review of the literature is presented in this article. Most of the previous studies have been performed in the 80’s or at the beginning of the 90’s. In this study, the relationship between wood density and Hounsfield numbers was investigated using a recent medical scanner. A linear relationship was fitted using a calibration data set which consisted in tropical wood samples representing a large range of densities ranging between 133 and 1319 kg m−3, and then validated using an independent data set (mainly temperate tree species). The fitted relationships were very strong (R2 > 0.999), whichever the tested scanner settings, with slight but significant effects of the current voltage and reconstruction filters. The RMSE values computed from the validation data set ranged between 5.4 and 7.7 kg m−3 for densities ranging between 364 and 821 kg m−3. In conclusion, this method of calibration enables the use of a medical scanner to obtain maps of wood density, in a fast and non destructive way, and with a very good accuracy. Very interesting perspectives are opened regarding biomass distribution within trees. Numéro de notice : A2009-610 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1051/forest/2009071 Date de publication en ligne : 25/11/2009 En ligne : https://www.afs-journal.org/articles/forest/full_html/2009/08/f09029/f09029.html Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=72893 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
IFN-001-P000694	PER	Revue	Nogent-sur-Vernisson	Salle périodiques	Exclu du prêt

X-ray photogrammetry of artificial joints / A.R. Turner-Smith in Photogrammetric record, vol 13 n° 75 (April - September 1990)  

Public [article]  inPhotogrammetric record > vol 13 n° 75 (April - September 1990) . - pp 347 - 366 Titre : X-ray photogrammetry of artificial joints Type de document : Article/Communication Auteurs : A.R. Turner-Smith, Auteur Année de publication : 1990 Article en page(s) : pp 347 - 366 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Photogrammétrie terrestre [Termes IGN] photogrammétrie médicale [Termes IGN] rayon X Numéro de notice : A1990-038 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.1111/j.1477-9730.1990.tb00691.x En ligne : https://doi.org/10.1111/j.1477-9730.1990.tb00691.x Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=25457 [article]

Exemplaires(2)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
106-90011	RAB	Revue	Centre de documentation	En réserve L003	Disponible
106-90012	RAB	Revue	Centre de documentation	En réserve L003	Disponible

Pulsar astronomy / A.G. Lyne (1990)

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Non-topographic photogrammetry / H.M. Karara (1989)

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A technique for anatomic feature extraction and tracking on sequential digital X-ray images / S. Curry in Photogrammetria, vol 42 n° 3 (December 1987)

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Real-time photogrammetry / M.C. Van Wijk (1986)

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Premier colloque image : traitement, synthèse, technologie et applications, 1. Volume 1 / Centre d'études des systèmes et des technologies avancées (1984)

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Premier colloque image : traitement, synthèse, technologie et applications, 2. Volume 2 / Centre d'études des systèmes et des technologies avancées (1984)

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Cours de physique, 3. 3, Ondes et corpuscules / M. Jouguet (1969)

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Congres SIP, Lisbonne, 1964 : commission 5 : les applications spéciales de la photogrammétrie ou la photogrammétrie des deux infinis / Maurice Carbonnell in Bulletin [Société Française de Photogrammétrie], n° 18 (Avril 1965)

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Manuel de photographie (sciences physiques et biologiques) / G. De Vaucouleurs (1956)

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