Y. Granjon - Academia.edu (original) (raw)
Papers by Y. Granjon
Le but de ce travail consiste a optimiser le rendement en puissance entre une bobine emettrice ex... more Le but de ce travail consiste a optimiser le rendement en puissance entre une bobine emettrice externe et une bobine receptrice implantee de maniere a transferer le maximum de puissance au systeme implantable a alimenter, ceci dans des applications de biotelemesure. Connaissant la distance entre les deux bobines, la puissance d'alimentation necessaire au dispositif implante, la resistance equivalente statique de ce dernier, la tension maximale et la frequence de la source externe, ainsi que les formes des deux bobines, nous utilisons une methode numerique d'optimisation pour le calcul du transfert optimal de puissance vers la bobine secondaire
La frequence, la gravite et le cout medical des escarres sacro-coccygiennes et ischiatiques chez ... more La frequence, la gravite et le cout medical des escarres sacro-coccygiennes et ischiatiques chez les paraplegiques ont incite a concevoir un systeme de prevention. Le systeme encourage le sujet a degager ses points d'appui a intervalles de temps reguliers. L'appui est controle par un capteur pneumatique et les signaux de prevention sont fournis par un synthetiseur vocal. Cette recherche originale est motivee par l'absence sur le marche de dispositifs efficaces permettant de reduire de facon suffisante la pression. Des tests cliniques ont ete effectues sur des sujets paraplegiques volontaires pour evaluer les performances du systeme
La mesure de contraintes osseuses in vivo chez l'homme est d'un grand interet en orthoped... more La mesure de contraintes osseuses in vivo chez l'homme est d'un grand interet en orthopedie, notamment pour apprehender les phenomenes subsequents a l'implantation d'une prothese totale de hanche. Cette mesure au niveau du femur ne peut s'envisager que par l'utilisation d'un capteur mesurant les deformations osseuses, associe a un systeme electronique de telemesure. Cet article presente un nouveau type de capteur de deformation, ayant un faible encombrement et s'implantant directement sur la surface osseuse par un unique point d'ancrage
Certains traumatismes dentaires de l'enfant nous conduisent a mettre en place une contention.... more Certains traumatismes dentaires de l'enfant nous conduisent a mettre en place une contention. Celle-ci peut etre realisee a partir de differents materiaux ou materiels: composite, kevlar, fil metallique et composite, verrous et fil orthodontique. Cependant le controle des mouvements dentaires parasites lie a l'utilisation de materiels orthodontiques pour la realisation d'une contention, semble peu etudie. Le but de ce travail est d'elaborer un capteur pour juger la neutralite d'un arc de contention apres sa mise en place. La conception de celui-ci fait appel aux theories de la resistance des materiaux et aux methodes d'analyse des contraintes (plus particulierement a l'extensometrie) qui permettent a partir de l'enregistrement des deformations de connaitre la charge appliquee
IFAC Proceedings Volumes, 1994
IFAC Proceedings Volumes, 1989
The new technique s for cancer healing call upon photo-chemical properties of new molecular compo... more The new technique s for cancer healing call upon photo-chemical properties of new molecular composites such as hemato-porphyrin , Those techniques have inducted Photo-Chemiotherapy which use the most recent experience in matter of medical lasers, Contrary to the most classical and already well-known effects of current medi cal laser beams, the expertness of photo-chemical effects, needs the very precise knowledge of the light diffusion and absorption phenomenons in biological ti ssue s, in order to define an efficient dosimetry, Fundamental results of quantum theory allow to acceed to a simple model of the phenomenons and informatic tools allow to get a very sati sfying simulation from which very important results can be obtained, This paper deals with the first results of this study, led in very close collaboration between the two laboratories,
Proceedings Eighth IEEE Symposium on Computer-Based Medical Systems, 1995
Presents a system that allows the acquisition of 2D echographical images that can later be used f... more Presents a system that allows the acquisition of 2D echographical images that can later be used for the reconstruction of a D representation of the human heart. The acquisition process is automatic, so that no interaction by the operator is necessary. The system is based on the so-called `rotational method' and is conceived such that it can be used with virtually any existing echograph. The 2D images are provided in a digitized form and can be used instantly for further processing
Images of the Twenty-First Century. Proceedings of the Annual International Engineering in Medicine and Biology Society
Proceedings of IEEE Systems Man and Cybernetics Conference - SMC, 1993
A specific articular exercise may be needed under particular circumstances in rehabilitation. In ... more A specific articular exercise may be needed under particular circumstances in rehabilitation. In such cases, it is very important to quantify the angular kinematics of movements which are imposed to the patient in order to attain firstly, a possible well-adapted rehabilitation and secondly, a clinical follow-up. This research is originated from the lack of user-friendly, versatile and inexpensive apparatus which
Proceedings of the IEEE 21st Annual Northeast Bioengineering Conference, 1995
Reconstruction of 3D objects from 2D data is a common problem in many different fields and especi... more Reconstruction of 3D objects from 2D data is a common problem in many different fields and especially medical imaging, e.g. CT and NMR. Most reconstruction methods presented so far, first define a three-dimensional matrix representing the final volume. In this volume the measured 2D data sets are placed. Then the object is reconstructed by filling the “empty space” using different
Proceedings of the IEEE 21st Annual Northeast Bioengineering Conference, 1995
IEEE International Conference on Systems, Man, and Cybernetics, 1993
A specific articular exercise may be needed under particular circumstances in rehabilitation. In ... more A specific articular exercise may be needed under particular circumstances in rehabilitation. In such cases, it is very important to quantify the angular kinematics of movements which are imposed to the patient in order to attain firstly, a possible well-adapted rehabilitation and secondly, a clinical follow-up. This research is originated from the lack of user-friendly, versatile and inexpensive apparatus which
Technology and health care : official journal of the European Society for Engineering and Medicine, 1994
For many applications in biomedical engineering, and especially for precise dosimetry in photodyn... more For many applications in biomedical engineering, and especially for precise dosimetry in photodynamic therapy, it is essential to determine the absorption and scattering of light in biological tissue very precisely. At present it is not possible to measure the absorption and scattering coefficient separately by using an endoscopic sensor based upon the backscattering phenomenon. In this paper, we propose a solution to this problem. We present a new model derived from Kubelka and Munk's theory, which is known to be suitable for the description of optical phenomena in tissue. Then we apply an algorithm often used in signal processing, the Auto Regressive with eXternal input or ARX model, which allows us to determine both optical coefficients separately. A first validation is done by numerical simulation, then measurements with phantoms were done. The results of both tests prove the model to be reliable and effective.
Medical & Biological Engineering & Computing, 1997
Management of dental trauma in children sometimes requires the use of dental splints, which can b... more Management of dental trauma in children sometimes requires the use of dental splints, which can be constructed from orthodontic materials. Past studies of the mechanical properties of dental splints have only been interested in their flexibility and not passivity. The purpose of this study is to determine the passivity of splints constructed from orthodontic materials. A specific data acquisition system, with a 2D transducer, is developed for evaluation of its neutrality. The transducer detects the displacements of the splinted tooth generated by the splint. The splints are constructed with 0.406 mm round, straight or Arch Blank preformed stainless-steel wires, with 0.559 mm standard edgewise brackets and with 0.254 mm stainless-steel or 3.05 mm elastomeric ligatures. Results show that mean output voltages generated by the splints range from 1.13 V to 2.48 V. The best control of passivity is obtained with the splints constructed with a preformed archwire and with elastomeric ligatures (p < 0.05), and the worst control is obtained with those constructed with a straight wire and with stainless-steel ligatures (p < 0.05).
Le but de ce travail consiste a optimiser le rendement en puissance entre une bobine emettrice ex... more Le but de ce travail consiste a optimiser le rendement en puissance entre une bobine emettrice externe et une bobine receptrice implantee de maniere a transferer le maximum de puissance au systeme implantable a alimenter, ceci dans des applications de biotelemesure. Connaissant la distance entre les deux bobines, la puissance d'alimentation necessaire au dispositif implante, la resistance equivalente statique de ce dernier, la tension maximale et la frequence de la source externe, ainsi que les formes des deux bobines, nous utilisons une methode numerique d'optimisation pour le calcul du transfert optimal de puissance vers la bobine secondaire
La frequence, la gravite et le cout medical des escarres sacro-coccygiennes et ischiatiques chez ... more La frequence, la gravite et le cout medical des escarres sacro-coccygiennes et ischiatiques chez les paraplegiques ont incite a concevoir un systeme de prevention. Le systeme encourage le sujet a degager ses points d'appui a intervalles de temps reguliers. L'appui est controle par un capteur pneumatique et les signaux de prevention sont fournis par un synthetiseur vocal. Cette recherche originale est motivee par l'absence sur le marche de dispositifs efficaces permettant de reduire de facon suffisante la pression. Des tests cliniques ont ete effectues sur des sujets paraplegiques volontaires pour evaluer les performances du systeme
La mesure de contraintes osseuses in vivo chez l'homme est d'un grand interet en orthoped... more La mesure de contraintes osseuses in vivo chez l'homme est d'un grand interet en orthopedie, notamment pour apprehender les phenomenes subsequents a l'implantation d'une prothese totale de hanche. Cette mesure au niveau du femur ne peut s'envisager que par l'utilisation d'un capteur mesurant les deformations osseuses, associe a un systeme electronique de telemesure. Cet article presente un nouveau type de capteur de deformation, ayant un faible encombrement et s'implantant directement sur la surface osseuse par un unique point d'ancrage
Certains traumatismes dentaires de l'enfant nous conduisent a mettre en place une contention.... more Certains traumatismes dentaires de l'enfant nous conduisent a mettre en place une contention. Celle-ci peut etre realisee a partir de differents materiaux ou materiels: composite, kevlar, fil metallique et composite, verrous et fil orthodontique. Cependant le controle des mouvements dentaires parasites lie a l'utilisation de materiels orthodontiques pour la realisation d'une contention, semble peu etudie. Le but de ce travail est d'elaborer un capteur pour juger la neutralite d'un arc de contention apres sa mise en place. La conception de celui-ci fait appel aux theories de la resistance des materiaux et aux methodes d'analyse des contraintes (plus particulierement a l'extensometrie) qui permettent a partir de l'enregistrement des deformations de connaitre la charge appliquee
IFAC Proceedings Volumes, 1994
IFAC Proceedings Volumes, 1989
The new technique s for cancer healing call upon photo-chemical properties of new molecular compo... more The new technique s for cancer healing call upon photo-chemical properties of new molecular composites such as hemato-porphyrin , Those techniques have inducted Photo-Chemiotherapy which use the most recent experience in matter of medical lasers, Contrary to the most classical and already well-known effects of current medi cal laser beams, the expertness of photo-chemical effects, needs the very precise knowledge of the light diffusion and absorption phenomenons in biological ti ssue s, in order to define an efficient dosimetry, Fundamental results of quantum theory allow to acceed to a simple model of the phenomenons and informatic tools allow to get a very sati sfying simulation from which very important results can be obtained, This paper deals with the first results of this study, led in very close collaboration between the two laboratories,
Proceedings Eighth IEEE Symposium on Computer-Based Medical Systems, 1995
Presents a system that allows the acquisition of 2D echographical images that can later be used f... more Presents a system that allows the acquisition of 2D echographical images that can later be used for the reconstruction of a D representation of the human heart. The acquisition process is automatic, so that no interaction by the operator is necessary. The system is based on the so-called `rotational method' and is conceived such that it can be used with virtually any existing echograph. The 2D images are provided in a digitized form and can be used instantly for further processing
Images of the Twenty-First Century. Proceedings of the Annual International Engineering in Medicine and Biology Society
Proceedings of IEEE Systems Man and Cybernetics Conference - SMC, 1993
A specific articular exercise may be needed under particular circumstances in rehabilitation. In ... more A specific articular exercise may be needed under particular circumstances in rehabilitation. In such cases, it is very important to quantify the angular kinematics of movements which are imposed to the patient in order to attain firstly, a possible well-adapted rehabilitation and secondly, a clinical follow-up. This research is originated from the lack of user-friendly, versatile and inexpensive apparatus which
Proceedings of the IEEE 21st Annual Northeast Bioengineering Conference, 1995
Reconstruction of 3D objects from 2D data is a common problem in many different fields and especi... more Reconstruction of 3D objects from 2D data is a common problem in many different fields and especially medical imaging, e.g. CT and NMR. Most reconstruction methods presented so far, first define a three-dimensional matrix representing the final volume. In this volume the measured 2D data sets are placed. Then the object is reconstructed by filling the “empty space” using different
Proceedings of the IEEE 21st Annual Northeast Bioengineering Conference, 1995
IEEE International Conference on Systems, Man, and Cybernetics, 1993
A specific articular exercise may be needed under particular circumstances in rehabilitation. In ... more A specific articular exercise may be needed under particular circumstances in rehabilitation. In such cases, it is very important to quantify the angular kinematics of movements which are imposed to the patient in order to attain firstly, a possible well-adapted rehabilitation and secondly, a clinical follow-up. This research is originated from the lack of user-friendly, versatile and inexpensive apparatus which
Technology and health care : official journal of the European Society for Engineering and Medicine, 1994
For many applications in biomedical engineering, and especially for precise dosimetry in photodyn... more For many applications in biomedical engineering, and especially for precise dosimetry in photodynamic therapy, it is essential to determine the absorption and scattering of light in biological tissue very precisely. At present it is not possible to measure the absorption and scattering coefficient separately by using an endoscopic sensor based upon the backscattering phenomenon. In this paper, we propose a solution to this problem. We present a new model derived from Kubelka and Munk's theory, which is known to be suitable for the description of optical phenomena in tissue. Then we apply an algorithm often used in signal processing, the Auto Regressive with eXternal input or ARX model, which allows us to determine both optical coefficients separately. A first validation is done by numerical simulation, then measurements with phantoms were done. The results of both tests prove the model to be reliable and effective.
Medical & Biological Engineering & Computing, 1997
Management of dental trauma in children sometimes requires the use of dental splints, which can b... more Management of dental trauma in children sometimes requires the use of dental splints, which can be constructed from orthodontic materials. Past studies of the mechanical properties of dental splints have only been interested in their flexibility and not passivity. The purpose of this study is to determine the passivity of splints constructed from orthodontic materials. A specific data acquisition system, with a 2D transducer, is developed for evaluation of its neutrality. The transducer detects the displacements of the splinted tooth generated by the splint. The splints are constructed with 0.406 mm round, straight or Arch Blank preformed stainless-steel wires, with 0.559 mm standard edgewise brackets and with 0.254 mm stainless-steel or 3.05 mm elastomeric ligatures. Results show that mean output voltages generated by the splints range from 1.13 V to 2.48 V. The best control of passivity is obtained with the splints constructed with a preformed archwire and with elastomeric ligatures (p < 0.05), and the worst control is obtained with those constructed with a straight wire and with stainless-steel ligatures (p < 0.05).