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Recommended Standards for the Routine Performance Testing of Diagnostic X-Ray SystemsInstitute of Physics and Engineering in Medicine, Scally, Andy J. January 2005 (has links)
This Report replaces IPEM Report 77 and provides essential guidance for anyone responsible for diagnostic X-Ray equipment. This
document gives clear advice on which routine performance tests are essential and which are desirable, where to get information on
how to do them, who should be doing them and how often they should be done. For many tests it also gives guidance as to when the
results indicate further action should be taken. This second edition takes into account the introduction of new technologies in medical
imaging including CR, DDR and image display devices.
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Contribution aux techniques pour enrichir l'espace moteur et l'espace visuel des dispositifs d'interaction bureautiqueAlmeida, Rodrigo Andrade Botelho de 06 November 2009 (has links)
De nombreux travaux ont montré que, à l’origine des limitations de l’interaction bureautique, il y a un manque à la fois d’espace moteur et d’espace visuel.Cette thèse explore des moyens pour optimiser l’usage de ces espaces.D’une part, à partir du constat que l’on contrôle la position et l’orientation d’un objet par un geste naturel, cette thèse étudie les bénéfices que peut offrir une souris dotée d’un capteur de rotation. Cette < souris rotative > permet à l’utilisateur de maîtriser avec aisance trois variables continues d’une tâche informatique. Un état de l’art présente des aspects perceptifs et moteurs des actions en question et les particularités ergonomiques et techniques d’un tel dispositif. Deux techniques d’interaction - visant à faciliter des tâches métier récurrentes - sont proposées :le réglage < quasi-intégral > et la < palette satellitaire >. Par ailleurs, une évaluation expérimentale compare la performance d’une souris rotative avec celle d’une souris traditionnelle.D’autre part, ce travail se penche sur les questions de la visualisation de documents dans le contexte des bibliothèques numériques. D’abord, il examine l’apport et la faisabilité technique de l’utilisation d’un dispositif d’affichage immersif pour la navigation dans un catalogue de titres virtuel. Puis, afin de faciliter l’inspection massive d’un lot de pages numérisées, il avance des techniques de visualisation zoomables et multi-focales. Ces dernières permettent, dans une recherche d’anomalies, de saisir vite les caractéristiques visuelles de quelques centaines de pages. Et cela grâce à un va-et-vient entre la vue d’ensemble et la navigation panoramique des détails. / Past research has suggested that among the reasons for the limitations of present desktop interaction style is the lack of both motor and visual space. The goal ofthis thesis is to optimize the use of such spaces. Based on the fact that one can control an object’s position and orientation through a natural movement, the first main contributioin of this thesis is to explorethe advantages of enhancing the sensing of the standard mouse througha rotation sensor. This < rotary mouse > allows one to easily control three continuous variables of a computer task. A survey presents the perceptual and motorissues of some rotary manipulations and also the technical and ergonomic requirements of such device. Two interaction techniques, aimed to simplify repetitive tasks, are proposed : the < nearly-integral selection > and the < satellite palette >.Furthermore, an experimental evaluation compares the performance of the rotarymouse with that of a standard one. The other main contribution of this work is to investigate document visualization issues in the context of digital libraries. First, it analyses the advantages and the technical feasibility of integrating an immersive display to an interface aimed to support navigation in a virtual catalog. Second, in order to inspect the quality of a batch of digitized pages, it explores some zoomable and multi-focal visualization techniques. The overview and the panoramic detail browsing enabled by such techniques try to help users, which have to identify the flaws resulted from the digitization process, to quickly grasp the visual characteristics of a large set of pages.
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Controle de qualidade em dispositivos de exibição de imagens utilizados em radiodiagnóstico empregando o padrão GSDF e JNDMesquita, Bruno Ribeiro de 17 February 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / In this work, a study has been done about the procedures for evaluating the quality of
image display devices (monitors) used in radio-anomaly, based on the analysis of the luminance
characteristic curve versus the lowest just noticiable difference (JND), taking
into account the time use of such equipment. The evaluated devices were of different of
manufactures, models, series and had different resolutions. The evaluation of the quality
of monitors exerts a strong influence on the image quality. For this evaluation of quality
control, in addition to methods and instruments traditionally employed, an alternative
method was used to measure luminance using electric and photometric quantities, which
was validated by comparison with data obtained using a photometer, which is a standard
meter of luminance. The quality control tests for evaluation of diffuse reflection, specular
reflection, internal reflection or blurring, resolution, noise, luminance and contrast
response and luminance uniformity were performed on devices with standard TG18 test
images in DICOM GSDF format, with several shades of gray. These images are made
available by the American Association of Physicists in Medicine (AAPM). The results
were analyzed based on the limits established for primary and secondary monitors established
in quality control protocols for radiodiagnostics, including one from the AAPM
and others from Europe. In the analyzes, the illuminance of the environments in which the
monitors were taken into account. The qualitative and quantitative results were correlated
with the time of use of the display devices. The software used to view the test images
were Radiant DICOM, Micro DICOM and Isyte Radiology. The results demonstrate the
relevance of monitoring the use time of these devices, classified as primary (diagnostic
use) and secondary (visualization only). It was verified among the monitored monitors,
used in general radiology, that those with resolution between 2 and 5 megapixels can be
classified as primary until a certain time of use; Among the analyzed devices with more
than 50,000 hours of use, some demonstrate a behavior equivalent to that of secondary
monitors. Monitoring the temporal evolution of the use of a device in radiodiagnosis is
important so that errors in medical diagnosis are avoided. Not only are the higher resolution devices suitable for diagnostic reports but also those with lower resolution since
their image display parameters comply with quality control recommendations. / Neste trabalho foi realizado um estudo sobre procedimentos de avalia¸c˜ao da qualidade
de dispositivos de exibi¸c˜ao de imagem (monitores) utilizados em radiodiagn´ostico, a partir
da an´alise da curva caracter´ıstica de luminˆancia versus a menor diferen¸ca detect´avel
de contraste (JND), levando em conta o tempo de uso desses equipamentos. Os dispositivos
avaliados foram de diferentes marcas de fabrica¸c˜ao, modelos, s´eries e possu´ıam
resolu¸c˜oes distintas. A avalia¸c˜ao da qualidade de monitores exerce forte influˆencia na
qualidade de imagem. Para essa avalia¸c˜ao de controle de qualidade, al´em dos m´etodos
e instrumentos tradicionalmente empregados, foi empregado um m´etodo alternativo para
medi¸c˜ao de luminˆancia utilizando grandezas el´etricas e fotom´etricas, que foram validadas
por compara¸c˜ao aos dados obtidos utilizando-se um fotˆometro, que ´e medidor padr˜ao
de luminˆancia. Os testes de controle de qualidade para avalia¸c˜ao de reflex˜ao difusa, reflex
˜ao especular, reflex˜ao interna ou velamento, resolu¸c˜ao, ru´ıdo, resposta de luminˆancia
e contraste e uniformidade de luminˆancia foram realizados nos dispositivos com imagens
padr˜ao teste TG18 em formato DICOM GSDF, com v´arios tons de cinza. Essas imagens
s˜ao disponibilizadas pela Associa¸c˜ao Americana dos F´ısicos em Medicina (AAPM). Os
resultados foram analisados com base nos limites estabelecidos para monitores prim´arios
e secund´arios estabelecidos em protocolos de controle de qualidade para radiodiagn´ostico,
incluindo um da AAPM e outros da Europa. Nas an´alises, levou-se em considera¸c˜ao a ilumin
ˆancia dos ambientes em que se encontravam os monitores. Os resultados qualitativos
e quantitativos foram correlacionados ao tempo de uso dos dispositivos de exibi¸c˜ao. Os
softwares utilizados para visualiza¸c˜ao das imagens testes foram o Radiant DICOM, Micro
DICOM e o Isyte Radio-logy. Os resultados demonstram a relevˆancia do acompanhamento
do tempo de uso desses dispositivos, que podem ser classificados como prim´arios
(uso em diagn´ostico) e secund´arios (visualiza¸c˜ao apenas). Foi verificado entre os monitores
aferidos, utilizados em radiologia geral, que aqueles com resolu¸c˜ao entre 2 e 5 megapixels
podem ser classificados como prim´arios at´e certo tempo de uso; entre os dispositivos
analisados com mais de 50.000 horas de uso, alguns demonstram um comportamento equivalente
ao de monitores secund´arios. O acompanhamento da evolu¸c˜ao temporal do uso de
um dispositivo no radiodiagn´ostico ´e importante, para que se evite erros no diagn´ostico
m´edico. N˜ao s´o os dispositivos de maior resolu¸c˜ao s˜ao adequados para laudos em radiodiagn
´ostico, mas tamb´em aqueles com menor resolu¸c˜ao, desde que seus parˆametros de
exibi¸c˜ao de imagem estejam de acordo com as recomenda¸c˜oes de controle de qualidade
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Contribution aux techniques pour enrichir l'espace moteur et l'espace visuel des dispositifs d'interaction bureautiqueAlmeida, Rodrigo Andrade Botelho de 06 November 2009 (has links)
De nombreux travaux ont montré que, à l’origine des limitations de l’interaction bureautique, il y a un manque à la fois d’espace moteur et d’espace visuel.Cette thèse explore des moyens pour optimiser l’usage de ces espaces.D’une part, à partir du constat que l’on contrôle la position et l’orientation d’un objet par un geste naturel, cette thèse étudie les bénéfices que peut offrir une souris dotée d’un capteur de rotation. Cette < souris rotative > permet à l’utilisateur de maîtriser avec aisance trois variables continues d’une tâche informatique. Un état de l’art présente des aspects perceptifs et moteurs des actions en question et les particularités ergonomiques et techniques d’un tel dispositif. Deux techniques d’interaction - visant à faciliter des tâches métier récurrentes - sont proposées :le réglage < quasi-intégral > et la < palette satellitaire >. Par ailleurs, une évaluation expérimentale compare la performance d’une souris rotative avec celle d’une souris traditionnelle.D’autre part, ce travail se penche sur les questions de la visualisation de documents dans le contexte des bibliothèques numériques. D’abord, il examine l’apport et la faisabilité technique de l’utilisation d’un dispositif d’affichage immersif pour la navigation dans un catalogue de titres virtuel. Puis, afin de faciliter l’inspection massive d’un lot de pages numérisées, il avance des techniques de visualisation zoomables et multi-focales. Ces dernières permettent, dans une recherche d’anomalies, de saisir vite les caractéristiques visuelles de quelques centaines de pages. Et cela grâce à un va-et-vient entre la vue d’ensemble et la navigation panoramique des détails. / Past research has suggested that among the reasons for the limitations of present desktop interaction style is the lack of both motor and visual space. The goal ofthis thesis is to optimize the use of such spaces. Based on the fact that one can control an object’s position and orientation through a natural movement, the first main contributioin of this thesis is to explorethe advantages of enhancing the sensing of the standard mouse througha rotation sensor. This < rotary mouse > allows one to easily control three continuous variables of a computer task. A survey presents the perceptual and motorissues of some rotary manipulations and also the technical and ergonomic requirements of such device. Two interaction techniques, aimed to simplify repetitive tasks, are proposed : the < nearly-integral selection > and the < satellite palette >.Furthermore, an experimental evaluation compares the performance of the rotarymouse with that of a standard one. The other main contribution of this work is to investigate document visualization issues in the context of digital libraries. First, it analyses the advantages and the technical feasibility of integrating an immersive display to an interface aimed to support navigation in a virtual catalog. Second, in order to inspect the quality of a batch of digitized pages, it explores some zoomable and multi-focal visualization techniques. The overview and the panoramic detail browsing enabled by such techniques try to help users, which have to identify the flaws resulted from the digitization process, to quickly grasp the visual characteristics of a large set of pages.
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Entwicklung und Anwendung der CARS-Mikroskopie zum Nachweis C-deuterierter WirkstoffeBergner, Gero Maximilian 07 October 2013 (has links)
Die vorliegende Dissertation befasst sich mit der Anwendung und Weiterentwicklung der CARS -Mikroskopie (CARS, (Coherent anti-Stokes Raman scattering)) zur Lokalisierung von Wirkstoffen in Zellen. Aufgrund einer C-Deuterierung dieser Wirkstoffe werden diese intrinsisch markiert und lassen sich nicht-invasiv mit Hilfe Raman-basierter Mikrospektroskopietechniken von Zellbestandteilen unterscheiden. Diese Arbeit widmet sich der für biomedizinische Anwendungen zu geringen Sensitivität und zu hohen Komplexität des experimentellen Aufbaus für CARS-Mikroskopie.
Auf der Anwendungsseite wurdenzunächst mittels quantitativer Raman- und CARS- Mikroskopie die Detektionsgrenzen C-deuterierter Stoffe bestimmt. Anhand von mit deuterierter Fettsäure inkubierter Makrophagen wurde chemischer Kontrast in Zellen qualitativ gezeigt.
Die Weiterentwicklung des experimentellen Aufbaus erfolgte durch den Einsatz von Impulsformern. Diese können das Anregungslicht in Amplitude und Phase formen und somit den Schwingungskontrast optimieren und den experimentellen Aufbau vereinfachen. Verwendet wurden dabei sowohl ein spatial light modulator (SLM) als auch ein akustooptischer Modulator (AOM), die in dieser Arbeit miteinander verglichen werden. Mit Hilfe einer photonischen Kristallfaser als spektral breite Lichtquelle und des AOM als spektraler Filter konnte der Aufbau vereinfacht und ein Schema zur Implementierung von Quasi-Multiplex CARS-Mikroskopie aufgebaut werden, welches ein schnelles Schalten zwischen verschiedenen bildgebenden Raman-Banden erlaubt.
Die automatisierte Optimierung des Schwingungskontrasts erfolgte schließlich durch den Einsatz des SLM, der mit Hilfe eines selbstlernenden Algorithmus den Schwingungskontrast von CARS-Bildern um bis zu 160 % verbessern konnte.
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A Degradation-based Burn-in Optimization for Light Display Devices with Two-phase Degradation Patterns considering Warranty Durations and Measurement ErrorsGao, Yong January 2017 (has links)
No description available.
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