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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
131

ADVANCED UNDERSTANDING OF THE OPTICAL PROPERTIES IN PHASE COMPENSATED LIQUID CRYSTAL DEVICES

Jang, Yong-Kyu 27 July 2007 (has links)
No description available.
132

Konstrukce rozhledny v Javorníkách / The Structure of a Viewing Tower in Javorníky

Kadlček, Dan January 2015 (has links)
The aim of diploma thesis is design and assessment of bearing structure of viewing tower on the mountain Makyta in Javorníky, which is designed from timber and steel. The shape of construction is variable of its height. Diameter of octagonal platform at ground level is 12 m, in the middle of construction is 7,7 m and on the top of the construction is 8,7 m. Viewing tower has 5 viewing platforms – the highest one is covered by roof. Wooden elements are designed from glued-laminated GL24h timber, steel elements are designed from steel of S235 grade. Main support elements of structure are wooden rectangular outer columns and steel circle center column. Total height of construction is 31 m. Static analysis has been accomplished by student version of the SCIA Engineer 2014 software.
133

Improving Peripheral Vision Through Optical Correction and Stimulus Motion

Lewis, Peter January 2016 (has links)
The loss of central vision subsequent to macular disease is often extremely debilitating. People with central field loss (CFL) must use other peripheral areas of the retina in order to see; areas with inferior resolution capacity, which are also affected by off-axis optical errors. The overall aim of the work encompassed by this thesis was to identify and evaluate methods of improving vision for people with CFL; with focus on the effects of off-axis optical correction and stimulus motion on resolution acuity and contrast sensitivity. Off-axis optical errors were measured using a commercially-available COAS-HD VR open-view aberrometer. We used adaptive psychophysical methods to evaluate grating resolution acuity and contrast sensitivity in the peripheral visual field; drifting gratings were employed to   measure the effect of motion on these two measures of visual performance. The effect of sphero-cylindrical correction and stimulus motion on visual performance in healthy eyes and in subjects with CFL was also studied; in addition, the effect of adaptive optics aberration correction was examined in one subject with CFL. The COAS-HD aberrometer provided rapid and reliable measurements of off-axis refractive errors. Correction of these errors gave improvements in low-contrast resolution acuity in subjects with higher amounts of oblique astigmatism. Optical correction also improved high-contrast resolution acuity in most subjects with CFL, but not for healthy subjects. Adaptive optics correction improved both high and low contrast resolution acuity in the preferred retinal locus of a subject with CFL. The effect of stimulus motion depended on spatial frequency; motion of 7.5 Hz improved contrast sensitivity for stimuli of low spatial frequency in healthy and CFL subjects. Motion of 15 Hz had little effect on contrast sensitivity for low spatial frequency but resulted in reduced contrast sensitivity for higher spatial frequencies in healthy subjects. Finally, high-contrast resolution acuity was relatively insensitive to stimulus motion in the periphery. This thesis has served to broaden the knowledge regarding peripheral optical errors, stimulus motion and their effects on visual function, both in healthy subjects and in people with CFL. Overall it has shown that correction of off-axis refractive errors is important for optimizing peripheral vision in subjects with CFL; the use of an open-view aberrometer simplifies the determination of these errors. In addition, moderate stimulus motion can have a beneficial effect on contrast sensitivity for objects of predominantly low spatial frequency.
134

A la rencontre de l'animal sauvage : dynamiques, usages et enjeux du récréotourisme faunique

Chanteloup, Elaine 06 1900 (has links)
Historiquement, les animaux sauvages ont toujours représenté une ressource pour les hommes, assurant la sécurité alimentaire des sociétés locales et traditionnelles. L’exploitation touristique de la faune implique dès lors une évolution dans les modes de vie, la culture et les identités locales. L’objectif de cette recherche doctorale est d’analyser le récréotourisme faunique. Les activités récréotouristiques autour de la faune sauvage traduisent une requalification de la ressource faune, ce qui a des impacts à la fois sur les espaces humains et non humains, les jeux de construction territoriale et sur les rapports développés à la faune sauvage. Ce travail analyse les rapports que les sociétés entretiennent avec la faune sauvage à travers les activités récréotouristiques de chasse et de vision. Ces deux formes de tourisme sont généralement opposées car le tourisme de vision est présenté comme un usage non-consomptif de la ressource alors que le tourisme de chasse est reconnu comme un usage consomptif de la ressource. Dépassant certaines idées reçues sur les pratiques de la chasse et une approche manichéenne entre ces différentes activités, il convient d’interroger les distinctions et / ou le rapport dialogique entre ces pratiques. Afin de conduire cette recherche, le choix d’une analyse comparative a été retenu, laquelle se propose de mettre en perspective différentes études de cas en France et au Canada. Ce travail comparatif permet de mieux comprendre les enjeux touristiques et territoriaux associés à la gestion de la faune sauvage et de penser la transférabilité des processus observés entre différents terrains d’études. D’un point de vue méthodologique, ce travail doctoral nous a conduite à définir un cadre analytique organisé autour de quatre entrées croisant des (i) aspects conceptuels, (ii) l’analyse d’archives, (iii) des méthodes d’observation ainsi que (iv) des outils d’analyse des rapports homme / faune via l’analyse de discours des populations touristiques. La première partie de ce travail présente le contexte théorique de l’étude et la démarche systémique de cette recherche (chapitre 1, 2 et 3). En termes de résultat, ces présupposés méthodologiques et théoriques nous ont permis d’analyser comment les dynamiques du récréotourisme faunique agissent, réagissent et rétroagissent sur l’ensemble du système territorial. Ainsi, la deuxième partie interroge l’organisation socio-spatiale des activités récréotouristiques de chasse et de vision (chapitre 4 et 5). Ces différentes formes de tourisme sont analysées en prenant en compte l’implantation de ces activités au sein des territoires, les attentes touristiques de la part des visiteurs, et les effets des différentes pratiques sur les populations fauniques. La troisième et dernière partie s’intéresse à l’évolution des rapports hommes / faune sauvage dans le temps et l’espace au regard des activités récréotouristiques développées. Le chapitre 6 s’intéresse aux rapports dialectiques entre processus de patrimonialisation et les usages acceptés ou non de la ressource faunique, alors que le chapitre 7 propose une réflexion sur les rapports hommes / animaux à l’échelle de l’individu en interrogeant l’éthique de chacun dans ses usages, ses comportements et ses pratiques développés autour de la faune sauvage. / Historically, wildlife has always been a resource for mankind by ensuring food safety to local and traditional societies. Wildlife tourism represents an evolution in the use of wildlife and affects livelihoods, culture and the local identities. The aim of this PhD research is to have a better understanding of what is wildlife tourism. This specific tourism causes a requalification of the resource, which has some impacts on human and non-human spaces, on the territorial building processes and on the relationship between men and animals. This research focuses particularly on these issues by studying wildlife viewing tourism and sport hunting tourism. These two kinds of tourism are usually in conflict because wildlife tourism is viewed as a non-consumptive tourism whereas hunting tourism is viewed as a consumptive tourism. Going beyond some common preconceptions on these different tourisms, we question the differences and/or the dialogical relationship between these practices. To conduct this research, we chose to lead a comparative analysis putting into perspective different case studies in France and in Canada. This comparative work allows a better understanding of tourism and territorial stakes linked to wildlife tourism and it allows to reflect on the transferability of processes observed between different fieldworks. From a methodological point of view, we have defined a framework to analyse wildlife tourism. This framework is based on conceptual aspects, analysis of archives, observation methods and discourse analysis. The first part of this work presents the theoretical context and introduces the systemic approach of this research (chapter 1, 2 and 3). These methodological and theoretical presuppositions are used to analyse how wildlife tourism dynamics act, react and retroact on the whole territorial system. The second part questions the socio-spatial organisation of wildlife viewing and hunting tourisms (chapters 4 and 5). These forms of tourisms are studied taking into account the settlement of these activities on space, the visitors’ expectations and the impacts on wildlife populations. The third and last part discusses the evolution of the relationship between humans and wildlife in time and space according to the tourism activity. Chapter 6 looks at the dialectical link between heritage processes and the uses of wildlife resource that are accepted or not, whereas chapter 7 suggests a reflection on human / animal interaction at the individual level questioning the people’s ethic in their use, behaviour and habits developed around wildlife.
135

Co-registration of eye movements and EEG during active vision

Dimigen, Olaf 19 December 2014 (has links)
Obwohl Blickbewegungen einen elementaren Bestandteil des natürlichen Sehens darstellen, werden hirnelektrische Korrelate der visuellen Verarbeitung im Elektroenzephalogramm (EEG) zumeist während passiver Stimulation des ruhenden Auges erfasst. Ein alternativer methodischer Zugang ist die Kopplung des EEG an Beginn oder Ende natürlich auftretender Augenbewegungen mit Hilfe simultanen, hochauflösenden Eye-Trackings (ET). Die resultierenden sakkaden- bzw. fixationskorrelierten Potentiale (SRPs/FRPs) wurden in zwei Forschungskontexten untersucht und angewendet. Der erste Teil der Arbeit (Publikation 1 & 2) befasst sich mit den elektrophysiologischen Korrelaten von Mikrosakkaden, unwillkürlichen Fixationsaugenbewegungen die auch während traditioneller EEG-Messungen auftreten. Es wird gezeigt, dass Mikrosakkaden trotz ihrer geringen Amplitude eine wesentliche, aber mit herkömmlichen Methoden kaum auszuschließende Quelle muskulärer und kortikaler Aktivität im EEG darstellen (mikrosakkadische SRPs), welche in der Mehrzahl experimenteller Durchgängen aktiv ist, und zur Fehlinterpretation reizgekoppelter Potentiale führen kann. Der zweite Teil der Arbeit demonstriert die Machbarkeit und Nützlichkeit von FRP-Analysen zur Untersuchung hirnelektrischer Prozesse beim Lesen. In Publikation 3 werden Einflüsse verschiedener Messartefakte sowie visuell-evozierter, motorischer und kognitiv modulierter Potentiale auf die FRP-Wellenform beschrieben und Methoden zur Signaloptimierung vorgeschlagen. Wir zeigen, dass sich im natürlichen Satzlesen der klassische N400 Wortvorhersagbarkeitseffekt reproduzieren und in Bezug zu Maßen der Fixationsdauer setzen lässt. In Publikation 4 wurde mittels FRPs das Ausmaß der parafovealen Wortverarbeitung bestimmt. Simultanes ET ist eine sinnvolle Ergänzung zur bestehenden EEG-Methodik, sowohl zur Kontrolle von Mikroaugenbewegungen, als auch zur Erforschung natürlichen Blickbewegungsverhaltens und Integration von Befunden der ET- und EEG-Forschung. / Although natural vision involves an active sampling of the environment with several saccadic eye movements per second, electroencephalographic (EEG) correlates of visual cognition are predominantly recorded under artificial conditions of prolonged fixation. An alternative approach to EEG analysis, explored in the present thesis, is to time-lock the signal not to passive stimulations, but to the on- or offsets of naturally occurring eye movements, yielding saccade- and fixation-related potentials (SRPs/FRPs). Using simultaneous high-resolution eye-tracking (ET), this technique was applied in two contexts. The first part of the thesis (publications 1 & 2) investigated brain-electric correlates of microsaccades, small involuntary eye movements, which occur despite attempted fixation during traditional EEG paradigms. In a series of experiments, we show that SRPs from microsaccades present a significant, but normally hidden source of visuocortical potentials that is active in most trials and can confound the interpretation of stimulus-locked data under specific conditions. The second part of the thesis assessed the feasibility and utility of using FRPs in the study of natural reading. Publication 3 provides a review of artifact sources, low-level factors, and high-level influences determining the FRP waveform in free viewing and proposes methods to optimize signal quality. We then replicate the N400 word predictability effect, a cornerstone of neurolinguistic research, in left-to-right sentence reading and relate N400 amplitude to measures of fixation time. In publication 4, the FRP technique was combined with gaze-contingent display manipulations to investigate the depth of parafoveal preprocessing in fluent reading. Our results show that simultaneous recordings improve the understanding of electrophysiological data recorded during fixation, extend the EEG’s methodological scope to naturalistic viewing scenarios, and help to integrate findings from EEG and ET research.
136

Watching Indonesian sinetron: imagining communities around the television

Ida, Rachmah January 2006 (has links)
This thesis is about the everyday cultural practices of communal television viewing by urban kampung people. It challenges the institutional frameworks and constructs about the television audience. To achieve this, the thesis looks at the cultural context of the television set and its uses in urban kampung households and the neighbourhood system. Studies on urban kampung community in Indonesia so far have focused on the socio-economic and cultural practices of the people in relation to state ideological matters (e.g. Guinness, 1989; Sullivan, 1994; Brenner, 1998). This thesis is an attempt to extend the investigation about the cultural practices of the kampung community in relation to media use in the era of competitive private television in the early 2000s. As those kampung people have existentially engaged in fashioning their own lives neither as rural subjects nor urban/ity subjects, their narratives in responding to televised images and representations (of women in particular) shape the particularity of the cultural scene of these marginalized subjects. Taking up their social economic background and the particularities of socio-cultural circumstances of the kampung, this present study takes a close look into the day-to-day communal viewing practice of the kampung female viewers of the most-watched local program on Indonesian television, that is sinetron (television drama). / Extending the argument of Ien Ang and others into the Indonesian context, the thesis concludes that the national television audience as a unified, atomistic and controllable entity, as is institutionally imagined, does not exist. Rather, watching television, particularly among the urban middle to lower class community, is a discursive practice overwhelmingly showing the diverse, particular, and unpredictable attitudes, which challenge the account of 'the audience' that characterises the industry, the state and, ironically, also the intellectual critical knowledge producers.
137

Filtrage de segments informatifs dans des vidéos / Informative segment filtering in video sequences

Guilmart, Christophe 20 December 2011 (has links)
Les travaux réalisés dans le cadre de cette thèse ont pour objectif d’extraire les différents segments informatifs au sein de séquences vidéo, plus particulièrement aériennes. L’interprétation manuelle de telles vidéos dans une optique de renseignement se heurte en effet au volume des données disponibles. Une assistance algorithmique fondée sur diverses modalités d’indexation est donc envisagée, dans l’objectif de repérer les "segments d’intérêt" et éviter un parcours intégral de la vidéo. Deux approches particulières ont été retenues et respectivement développées au sein de chaque partie. La partie 1 propose une utilisation des conditions de prise de vue (CPDV) comme modalités d’indexation. Une évaluation de la qualité image permet ainsi de filtrer les segments temporels de mauvaise qualité et donc inexploitables. La classification du mouvement image apparent directement lié au mouvement caméra, fournit une indexation de séquences vidéo en soulignant notamment les segments potentiels d’intérêt ou au contraire les segments difficiles présentant un mouvement très rapide ou oscillant. La partie 2 explore le contenu dynamique de la séquence vidéo, plus précisément la présence d’objets en mouvement. Une première approche locale en temps est présentée. Elle filtre les résultats d’une première classification par apprentissage supervisé en exploitant les informations de contexte, spatial puis sémantique. Différentes approches globales en temps sont par la suite explorées. De telles approches permettent de garantir la cohérence temporelle des résultats et réduire les fausses alarmes. / The objective of this thesis is to extract the informative temporal segments from video sequences, more particularly in aerial video. Manual interpretation of such videos for information gathering faces an ever growing volume of available data. We have thus considered an algorithmic assistance based on different modalities of indexation in order to locate "segments of interest" and avoid a complete visualization of the video. We have chosen two methods in particular and have respectively developed them in each part of this thesis. Part 1 describes how viewing conditions can be used as a method of indexation. The assessment of image quality enables to filter out the temporal segments for which the quality is low and which can thus not be exploited. The classification of global image motion, which is directly linked to camera motion, leads to a method of indexation for video sequences. Indeed, it emphasizes possible segments of interest or, conversely, difficult segments for which motion is very fast or oscillating. Part 2 focuses on the dynamic content of video sequences, especially the presence of moving objects. We first present a local (in time) approach. This approach refines the results obtained after a first classification by supervised learning by using contextual information, spatial then semantic information. We have then investigated several methods for moving object detection which are global in time. Such approaches aim to enforce the temporal consistency of the detected objects and to reduce false detections.
138

Vertical Field Switching Blue Phase Liquid Crystals For Field Sequential Color Displays

Cheng, Hui-Chuan 01 January 2012 (has links)
Low power consumption is a critical requirement for all liquid crystal display (LCD) devices. A field sequential color (FSC) LCD was proposed by using red (R), green (G) and blue (B) LEDs and removing the lossy component of color filters which only transmits ~30% of the incoming white light. Without color filters, FSC LCDs exhibit a ~3X higher optical efficiency and 3X higher resolution density as compared to the conventional color filters-based LCDs. However, color breakup (CBU) is a most disturbing defect that degrades the image quality in FSC displays. CBU can be observed in stationary or moving images. It manifests in FSC LCDs when there is a relative speed between the images and observers’ eyes, and the observer will see the color splitting patterns or rainbow effect at the boundary between two different colors. In Chapter 2, we introduce a five-primary display by adding additional yellow(Y) and cyan(C) colors. From the analysis and simulations, five primaries can provide wide color gamut and meanwhile the white brightness is increased, as compared to the three-primary. Based on the five-primary theorem, we propose a method to reduce CBU of FSC LCDs by using RGBYC LEDs instead of RGB LEDs in the second section. Without increasing the sub-frame rate as three-primary LCDs, we can reduce the CBU by utilizing proper color sequence and weighting ratios. In addition, the color gamut achieves 140% NTSC and the white brightness increases by more than 13%, as compared to the three-primary FSC LCDs. Another strategy to suppress CBU is using higher field frequency, such as 540 Hz or even up to 1000 Hz. However, this approach needs liquid crystals with a very fast response time (
139

Analysing User Viewing Behaviour in Video Streaming Services

Markou, Ioannis January 2021 (has links)
The user experience offered by a video streaming service plays a fundamental role in customer satisfaction. This experience can be degraded by poor playback quality and buffering issues. These problems can be caused by a user demand that is higher than the video streaming service capacity. Resource scaling methods can increase the available resources to cover the need. However, most resource scaling systems are reactive and scale up in an automated fashion when a certain demand threshold is exceeded. During popular live streaming content, the demand can be so high that even by scaling up at the last minute, the system might still be momentarily under-provisioned, resulting in a bad user experience. The solution to this problem is proactive scaling which is event-based, using content-related information to scale up or down, according to knowledge from past events. As a result, proactive resource scaling is a key factor in providing reliable video streaming services. Users viewing habits heavily affect demand. To provide an accurate model for proactive resource scaling tools, these habits need to be modelled. This thesis provides such a forecasting model for user views that can be used by a proactive resource scaling mechanism. This model is created by applying machine learning algorithms to data from both live TV and over-the-top streaming services. To produce a model with satisfactory accuracy, numerous data attributes were considered relating to users, content and content providers. The findings of this thesis show that user viewing demand can be modelled with high accuracy, without heavily relying on user-related attributes but instead by analysing past event logs and with knowledge of the schedule of the content provider, whether it is live tv or a video streaming service. / Användarupplevelsen som erbjuds av en videostreamingtjänst spelar en grundläggande roll för kundnöjdheten. Denna upplevelse kan försämras av dålig uppspelningskvalitet och buffertproblem. Dessa problem kan orsakas av en efterfrågan från användare som är högre än videostreamingtjänstens kapacitet. Resursskalningsmetoder kan öka tillgängliga resurser för att täcka behovet. De flesta resursskalningssystem är dock reaktiva och uppskalas automatiskt när en viss behovströskel överskrids. Under populärt livestreaminginnehåll kan efterfrågan vara så hög att även genom att skala upp i sista minuten kan systemet fortfarande vara underutnyttjat tillfälligt, vilket resulterar i en dålig användarupplevelse. Lösningen på detta problem är proaktiv skalning som är händelsebaserad och använder innehållsrelaterad information för att skala upp eller ner, enligt kunskap från tidigare händelser. Som ett resultat är proaktiv resursskalning en nyckelfaktor för att tillhandahålla tillförlitliga videostreamingtjänster. Användares visningsvanor påverkar efterfrågan kraftigt. För att ge en exakt modell för proaktiva resursskalningsverktyg måste dessa vanor modelleras. Denna avhandling ger en sådan prognosmodell för användarvyer som kan användas av en proaktiv resursskalningsmekanism. Denna modell är skapad genom att använda maskininlärningsalgoritmer på data från både live-TV och streamingtjänster. För att producera en modell med tillfredsställande noggrannhet ansågs ett flertal dataattribut relaterade till användare, innehåll och innehållsleverantörer. Resultaten av den här avhandlingen visar att efterfrågan på användare kan modelleras med hög noggrannhet utan att starkt förlita sig på användarrelaterade attribut utan istället genom att analysera tidigare händelseloggar och med kunskap om innehållsleverantörens schema, vare sig det är live-tv eller tjänster för videostreaming.
140

Détermination automatique de l'incidence optimale pour l'observation des lésions coronaires en imagerie rotationnelle R-X / Automatic determination of optimal viewing angle for the coronary lesion observation in rotationnal X-ray angiography

Feuillâtre, Hélène 10 June 2016 (has links)
Les travaux de cette thèse s’inscrivent dans le cadre du planning de traitements minimalement invasifs des lésions des artères coronaires. Le cardiologue réalise un examen coronarographique, puis dans la continuité, une angioplastie transluminale. L’angiographie rotationnelle à rayons X permet de visualiser sous différentes incidences 2D la lumière des artères coronaires sur plusieurs cycles cardiaques et aussi d’obtenir une reconstruction 3D+T des arbres coronaires. A partir de cette séquence, notre objectif est de déterminer automatiquement une incidence optimale 2D du segment sténosé compatible avec les angles du C-arm afin d’aider le cardiologue lors de l’intervention.Différentes étapes sont considérées pour calculer la position angulaire optimale du C-arm. Afin de suivre la zone de lésion durant le cycle cardiaque, une première méthode est proposée pour mettre en correspondance tous les arbres de la séquence 3D+T. Tout d’abord, un appariement deux à deux des arbres successifs est réalisé afin de construire un arbre d’union. Ces derniers sont ensuite fusionnés afin d’obtenir un arbre mosaïque représentant l’arbre le plus complet de la séquence. L’utilisation de mesures de similarités géométriques et hiérarchiques ainsi que l’insertion de nœuds artificiels permet de prendre en compte les différents mouvements non-rigides des artères coronaires subits au cours du cycle cardiaque et les variations topologiques dû à leurs extractions. Cet appariement nous permet de proposer une deuxième méthode afin d’obtenir une vue angiographique 2D optimale de la zone de lésion tout le long du cycle cardiaque. Cette incidence est proposée spécifiquement pour trois types de région d’intérêt (segment unique, segment multiple ou bifurcation) et est calculée à partir de quatre critères (raccourcissement, chevauchement interne et externe ou angle d’ouverture de bifurcation). Une vue 2D déployée du segment projeté avec le moins de superposition avec les structures vasculaires avoisinantes est obtenue. Nous donnons également la possibilité au cardiologue d’avoir une incidence optimale privilégiant soit le déploiement du stent ou soit le guidage d’outils de la racine de l’arbre à la zone sténosée. Nos différents algorithmes ont été évalués sur une séquence réelle de 10 phases segmentées à partir d’un CT et de 41 séquences simulées. / The thesis work deals with the planning of minimally invasive surgery of coronary artery lesions. The physician performs a coronarography following by a percutaneous transluminal angioplasty. The X-ray rotational angiography permits to visualize the lumen artery under different projection angles in several cardiac cycles. From these 2D projections, a 3D+T reconstruction of coronary arteries can be obtained. Our goal is to determine automatically from this 3D+T sequence, the optimal angiographic viewing angle of the stenotic segment. Several steps are proposed to compute the optimal angular position of the C-arm. Firstly, a mosaic-based tree matching algorithm of the 3D+T sequence is proposed to follow the stenotic lesion in the whole cardiac cycle. A pair-wise inexact tree matching is performed to build a tree union between successive trees. Next, these union trees are merged to obtain the mosaic tree which represents the most complete tree of the sequence. To take into account the non-rigid movement of coronary arteries during the cardiac cycle and their topology variations due to the 3D reconstruction or segmentation, similarity measures based on hierarchical and geometrical features are used. Artificial nodes are also inserted. With this global tree sequence matching, we propose secondly a new method to determine the optimal viewing angle of the stenotic lesion throughout the cardiac cycle. This 2D angiographic view which is proposed for three regions of interest (single segment, multiple segment or bifurcation) is computed from four criteria: the foreshortening, the external and internal overlap and the bifurcation opening angle rates. The optimal view shows the segment in its most extended and unobstructed dimension. This 2D view can be optimal either for the deployment of the stent or for the catheter guidance (from the root to the lesion). Our different algorithms are evaluated on real sequence (CT segmentation) and 41 simulated sequences.

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