Download or read book Imagerie et d tection ultrasonores par corr lation written by Baroudi El Khaldi and published by . This book was released on 2003 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: En échographie ultrasonore classique, l'extraction de signatures à partir d'échos est basée sur des traitements de déconvolution temporelle ou fréquentielle. La détection basée sur la corrélation nécessite l'utilisation de signaux codés, continus ou discrets. Les signaux discrets fournissent une bonne dynamique et limitent les artéfacts. La résolution est simultanément améliorée dans la cas des séquences pseudo-aléatoires binaires. L'étude des corrélateurs à un bit et multibits est présentée, pour des cibles isolées ou multiples. Les influences du moyennage, du sur-échantillonnage, de la précision de quantification numérique, et de la bande passante du système sont mises en évidence. Une architecture basée sur une approche logicielle et le stockage des signaux donne accès à des techniques de post-traitement numérique. Plusieurs expériences sont présentées, qui mettent en évidence les performances et avantages de la détection par corrélation.
Download or read book CONCEPTION ET REALISATION D UN ECHOGRAPHE A CORRELATION written by Marcel Gindre and published by . This book was released on 1987 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt: AMELIORATION DES PERFORMANCES DES ECHOGRAPHES ACTUELS PAR UTILISATION D'UNE EMISSION CODEE, LE CODAGE ADAPTE A LA MESURE DES DISTANCES
Download or read book Review of Progress in Quantitative Nondestructive Evaluation written by Donald O. Thompson and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 2348 pages. Available in PDF, EPUB and Kindle. Book excerpt: These Proceedings, consisting of Parts A and B, contain the edited versions of most of the papers presented at the annual Review of Progress in Quantitative Nondestructive Evaluation held at the University of Washington, Seattle on July 30 to August 4, 1995. The Review was organized by the Center for NDE at Iowa State University, in cooperation with the Ames Laboratory of the USDOE, the American Society of Nondestructive Testing, the Department of Energy, the National Institute of Standards and Technology, the Federal Aviation Administration, the National Science Foundation IndustryiUniversity Cooperative Research Centers, and the Working Group in Quantitative NDE. This year's Review of Progress in QNDE was attended by approximately 450 participants from the US and many foreign countries who presented over 375 papers. The meeting was divided into 36 sessions with as many as four sessions running concurrently. The Review covered all phases of NDE research and development from fundamental investigations to engineering applications or inspection systems, and it included many important methods of inspection science from acoustics to x-rays. In the last several years, the Review has stabilized at about its current size. Most participants seem to agree it is large enough to permit a full-scale overview of the latest developments but still small enough to retain the collegial atmosphere which has marked the Review since its inception. The Proceedings are structured in a format to reflect the organization of the Review itself, producing a more logical organization for both the meeting and the present volume.
Download or read book ETUDE ET REALISATION D UN SYSTEME D IMAGERIE ULTRASONORE TRAVAILLANT EN EMISSION CODEE written by Jean-Yves Le Huérou and published by . This book was released on 1993 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: LA QUALITE ACTUELLE DES IMAGES EN ECHOGRAPHIE ULTRASONORE EST EN PARTIE DUE AU COMPROMIS ENTRE LA RESOLUTION ET LA PROFONDEUR D'EXPLORATION. POUR AMELIORER LA RESOLUTION AXIALE, IL FAUT UTILISER DES IMPULSIONS TRES BREVES ET AUGMENTER LA FREQUENCE DE L'ONDE EMISE. LES MILIEUX EXPLORES ATTENUENT L'ONDE D'AUTANT PLUS QUE SA FREQUENCE EST ELEVEE ; LA DETECTION DU SIGNAL RETRODIFFUSE EST ALORS D'AUTANT PLUS DIFFICILE QUE SA FREQUENCE OU SA PROFONDEUR D'EXPLORATION AUGMENTE. EN CODANT L'ONDE EMISE, IL EST POSSIBLE D'EXTRAIRE LE SIGNAL RETRODIFFUSE DU BRUIT AMBIANT. POUR CE FAIRE NOUS AVONS UTILISE LES TECHNIQUES DE CORRELATION ENTRE L'ONDE DETECTEE ET LE CODE EMIS. LE CHOIX DU SIGNAL CODE INFLUENCE FORTEMENT LA QUALITE DES IMAGES. CELLE-CI EST TRIBUTAIRE DU COMPROMIS ENTRE LA MAXIMALISATION DU RAPPORT SIGNAL A BRUIT ET LA MINIMISATION DES LOBES SECONDAIRES DE LA FONCTION D'AUTOCORRELATION DU CODE. DEUX CODES SEMBLENT PARTICULIEREMENT BIEN ADAPTES A L'IMAGERIE ULTRASONORE. LES SERIES COMPLEMENTAIRES DONT LA FONCTION D'AUTOCORRELATION EST EXEMPTE DE LOBES SECONDAIRES : LE RAPPORT ENTRE L'AMPLITUDE DU LOBE PRINCIPAL DE LA FONCTION D'AUTOCORRELATION ET L'AMPLITUDE DES LOBES SECONDAIRES EST THEORIQUEMENT INFINI. LES CODES PSEUDOALEATOIRES POUR LESQUELS CE RAPPORT CROIT AVEC LA LONGUEUR DU CODE EMIS. LE PROTOTYPE D'ECHOGRAPHIE PAR CORRELATION QUE NOUS AVONS MIS AU POINT PERMET LA REALISATION DES IMAGES EN EMISSION CODEE. NOUS PRESENTONS DES IMAGES D'OBJETS SIMPLES REALISEES EN INSONIFIANT LE MILIEU SOIT AVEC UNE SEQUENCE CODEE, SOIT AVEC UNE IMPULSION BREVE. LES RESULTATS OBTENUS MONTRENT QUE CONTRAIREMENT AUX TECHNIQUES IMPULSIONNELLES L'EMISSION CODEE PERMET D'OBTENIR DES IMAGES D'OBJETS PLACES DANS DES MILIEUX FORTEMENT ATTENUANTS. LA DISCUSSION DES RESULTATS PERMET DE PRECISER LES APPLICATIONS POTENTIELLES DE L'ECHOGRAPHIE PAR EMISSION CODEE.
Download or read book Ultrasonic Detection Using Correlation Images Preprint written by and published by . This book was released on 2006 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: In ultrasonics, image formation and detection are generally based on signal amplitude. In this paper, we describe an amplitude independent approach for imaging and detection based on the similarity of adjacent signals, quantified by the correlation coefficient calculated between A-scans. Correlation coefficient images are introduced and shown with C-scan images to demonstrate flat-bottom-hole and crack detection in experimental data and planar defect detection at very low signal-to-noise ratio using simulated data. Receiver operating characteristic (ROC) analysis compares the new correlation method and the classical method.
Download or read book APPLICATIONS DE METHODES DE CORRELATION A L ESTIMATION DE PARAMETRES TISSULAIRES EN ECHOGRAPHIE MEDICALE written by CLAIRE.. LE FLOCH and published by . This book was released on 1999 with total page 203 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'ECHOGRAPHIE EST UNE TECHNIQUE NON INVASIVE D'IMAGERIE DONT LES APPLICATIONS CLINIQUES SONT DE PLUS EN PLUS NOMBREUSES. LES INFORMATIONS CONTENUES DANS L'IMAGE DE GRIS, PEUVENT ETRE ENRICHIES PAR LE BIAIS DE TRAITEMENTS DES SIGNAUX RF. DES DEPLACEMENTS DE STRUCTURES PEUVENT AINSI ETRE ESTIMES PAR INTERCORRELATIONS DES SIGNAUX RF. CE TRAVAIL PORTE SUR L'ANALYSE DE TELS DEPLACEMENTS GENERES PAR DEUX TYPES DE PHENOMENES : - L'APPLICATION D'UNE CONTRAINTE SUR LE MILIEU. LE BUT EST D'ESTIMER L'ELASTICITE DU MILIEU A PARTIR DE L'ANALYSE DES MOUVEMENTS LOCAUX DANS LE MILIEU. UN OUTIL DE SIMULATION PERMET DE COMPRENDRE L'EFFET DES NOMBREUX PARAMETRES DU TRAITEMENT SUR LA PRECISION DES MESURES DE DEPLACEMENT ET DE DEFORMATION. LES LIMITES DE L'INTERPRETATION DE L'IMAGERIE DE DEFORMATION NOUS CONDUISENT ENSUITE A ENVISAGER UNE PROCEDURE DE RECONSTRUCTION DU MODULE ELASTIQUE. L'ESTIMATION EST TRAITEE SELON UNE APPROCHE PROBLEME INVERSE. UNE NOUVELLE METHODE DE REGULARISATION DE L'INVERSION EST ADAPTEE DES PROBLEMES DE TOMOGRAPHIE D'IMPEDANCE ELECTRIQUE POUR L'ELASTOGRAPHIE. ELLE REPOSE SUR LE CALCUL D'UNE MATRICE DE REGULARISATION UNIFORMISANT LA VARIANCE DE LA RECONSTRUCTION. DES RESULTATS SUR DONNEES SIMULEES MONTRENT L'APPORT DE LA TECHNIQUE. - LES VARIATIONS DE TEMPERATURE INDUITES PAR UNE EXPERIENCE DE THERAPIE PAR ULTRASONS FOCALISES. LE BUT EST LE CONTROLE NON INVASIF DE LA TEMPERATURE. LES MOUVEMENTS DU SPECKLE SONT DUS A LA VARIATION DE LA VITESSE DE PROPAGATION AVEC LA TEMPERATURE. CONNAISSANT CE PARAMETRE, ON ESTIME LA VARIATION DE TEMPERATURE A PARTIR DE LA MESURE DES DEPLACEMENTS LOCAUX DANS LE MILIEU. CETTE METHODE NOUS A PERMIS DE METTRE EN EVIDENCE DES PHENOMENES DE DEFOCALISATION DES FAISCEAUX ULTRASONORES AU COURS DE L'INSONIFICATION. LA ZONE CHAUFFEE AGIT COMME UNE LENTILLE THERMIQUE VARIABLE POUR LE FAISCEAU, ET DES SIMULATIONS DU FAISCEAU D'HYPERTHERMIE MONTRENT QUE LA DEFORMATION SUBIE ENGENDRE UN DEPLACEMENT SIGNIFICATIF DU POINT FOCAL.
Download or read book Sonomammography written by P. B. Guyer and published by . This book was released on 1987-10-14 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt: This atlas demonstrates the interplay between x-ray mammography and sonomammography through examples of the same lesion imaged by different ultrasound techniques. This permits radiologists who may have only one of these techniques available to use it for accurate evaluation of breast problems. Presentation is based on analysis of 2000 ultrasound examinations, primarily by direct-contact static scanning rather than water-path techniques. Illustrations in each chapter are preceded by in-depth supporting descriptions as well as analysis of the ultrasound appearances. Extensively illustrated.
Download or read book HF tijdschrift written by and published by . This book was released on 1995 with total page 504 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ultrasound Elastography written by Monica Lupsor-Platon and published by BoD – Books on Demand. This book was released on 2020-03-04 with total page 148 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elastography, the science of creating noninvasive images of mechanical characteristics of tissues, has been rapidly evolving in recent years. The advantage of this technique resides in the ability to rapidly detect and quantify the changes in the stiffness of soft tissues resulting from specific pathological or physiological processes. Ultrasound elastography is nowadays applied especially on the liver and breast, but the technique has been increasingly used for other tissues including the thyroid, lymph nodes, spleen, pancreas, gastrointestinal tract, kidney, prostate, and the musculoskeletal and vascular systems. This book presents some of the applications of strain and shear-wave ultrasound elastography in hepatic, pancreatic, breast, and musculoskeletal conditions.
Download or read book Cumulated Index Medicus written by and published by . This book was released on 1976 with total page 1520 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book MRI of the Body written by Daniel Vanel and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 390 pages. Available in PDF, EPUB and Kindle. Book excerpt: As with the introduction of x -ray computed tomography, much of the initial development of magnetic resonance applications tended to focus on the central nervous system. The development of magnetic resonance imaging applications to other organ systems such as the chest, abdomen, pelvis and extremities has lagged somewhat behind, awaiting technical improvements, and a broader user base. The past two years have seen a marked increase in imaging applications throughout the body, most notably the musculoskeletal system. It is in this regard, that MRI of the Body is a welcome arrival as a text which describes both basic principles of magnetic resonance ima ging and surveys the current status of magnetic resonance imaging applications throughout the body. The volume is concise, focused, clinically oriented, and abun dantly illustrated. In each organ system, the appropriate technical approach is discussed, the normal anatomic features are reviewed, and the range of pathologic appearances which may be encountered are described. The authors of the chapters provide a balanced overview of MR applications and describe both present limitations and future potential of magnetic resonance imaging applications in the organ system described.
Download or read book Physiological Monitoring and Instrument Diagnosis in Perinatal and Neonatal Medicine written by Yves W. Brans and published by CUP Archive. This book was released on 1995-07-28 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explains and illustrates the principles and application of commonly used technologies in perinatal and neonatal medicine.
Download or read book Acoustical Imaging written by Leonardo Marotti and published by Springer Science & Business Media. This book was released on 1996 with total page 858 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contains 131 papers presented at the September 1995 symposium. Arrangement is in sections on the mathematics and physics of acoustical imaging, novel approaches in biomedical imaging, tissue characterization, flow imaging, transducers and arrays, imaging systems and techniques, underwater and indust
Download or read book Acoustical Imaging written by L. Masotti and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 834 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains 131 of the papers presented at the 22nd International Symposium on Acoustical Imaging. This meeting, which was held for the first time in Florence, Italy, on September 3-6, 1995, allowed an intense and friendly exchange of ideas between over 150 researchers from 26 different countries of Europe (70%), America (20%), Asia and Australia (10%). The Symposium started on Sunday, September 3, with the opening Session held in the magnificent 'Salone dei 500' in Palazzo Vecchio; this included invited talks by Peter WeHs and Hua Lee, who reviewed the State of the Art in Acoustical Imaging research. One hundred and forty papers, selected from the nearly 200 submitted Abstracts, were presented in 11 non-parallel oral Sessions and one Poster Session. This year a 'Best Poster' award was introduced, which was won by V. Miette, M. Fink and F. Wu. Also, a special session on Acoustical Microscopy was organized by Walter Arnold, in which invited speakers Ioie Iones, Oleg Kolosov, Andrew Briggs and Ute Rabe reviewed the capabilities of this em erging topic.
Download or read book Abstracts written by Excerpta Medica Foundation and published by . This book was released on 1973 with total page 566 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mathematical Reviews written by and published by . This book was released on 1980 with total page 804 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Air and Spaceborne Radar Systems written by Philippe Lacomme and published by William Andrew. This book was released on 2001 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Intended for actual users of radar, the book focuses on the history, main principles, functions, modes, properties and specific nature of modern airborne radar. It examines radar's role within the system when carrying out its assigned missions, showing the possibilities of radar, it's limitations and a discussion of how radar may evolve in the future.
