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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.
31

The Physiological Effect of Colored Background on One's Ability to See Colors

Waldrip, Rankin Carroll 08 1900 (has links)
This study is an attempt to understand if backgrounds with color impact physiology and the ability of a viewer to see color.
32

Procedurally Generated Eye Features for Real-time Applications

Nyberg, Sebastian January 2021 (has links)
Background. As computing power has increased over the years, larger parts of the digital graphics industries are moving towards using real-time rendering for their solutions. The fast iteration and visual response help make the creative processes and communication more accessible in both the desktop and smartphone markets. One noticeably growing area using real-time rendering is the communication between people and audiences using online chat applications with virtual avatars. As humans, social interaction is essential to every aspect of our health. The requirements of remote communications to satisfy the needs of social interaction are facial expressions. Facial expressions involve motion. Thus making real-time rendering mandatory for having facial expressions in computer-generated images. This thesis shows the performance result of having real-time procedural-generated eye features. Objectives. This thesis is based on an experiment by developing a data set of duration for computing different visual aspects of anime eyes, the aim is to help inform the creation of more complete and optimized shader solutions. The objectives of this thesis are to produce a profiling application, produce a collection of eye references, produce a collection of visual eye features, produce shaders based on the collections, and measure the time performance of the shaders. Method. Doing this experiment involves producing a profiling application in the C++ programming language using the OpenGL graphics API. The profiling application can render a set of shaders and measure time metrics. The experiment is executed on two different computers with different specifications. By gathering a collection of eye references from online resources, targeting popular media in the anime style, a collection of visual eye features can be established with common and unique attributes. The collections allow for the creation of a set of shaders that replicate the collected eye features. With the profiling application and shaders, a data collection of time metrics are composed. Results. The final results of the profiling experiment have a collection of 29 shaders representing different eye features. The profiling tests gave the results of how many milliseconds it took for a set number of frames to render each produced shader. This result is shown with the help of two different graphs for each computer that executed the experiment. Deconstructing the resulting data helps to analyze and distinguish interesting aspects. Conclusions. From the result of this thesis experiment, the conclusion can be made that an eye feature by itself is a fast process for the GPU to compute on its own. Aset of eye features combined to create a final eye shader including animation and eye tracking is a valid future work section regarding this thesis experiment.
33

Mathematics of Human Eyes

Gonzalez Castro, Gabriela, Fitt, A.D. January 2003 (has links)
We illustrate here how a range of fluid and solid mechanics problems relevant to the human eye have been combined in a continuing PhD study. Anterior chamber flow, the solid mechanics of tonometry, the effects of scleral buckle surgery and the mechanics of retinal detachment are all discussed. Finally, a number of other aye problems that are amenable to a theoretical mechanics treatment are proposed.
34

Lord Jim and Under Western Eyes: Two Treatments of Guilt and Atonement

Butler, Francis January 1982 (has links)
No description available.
35

Unusual eye design: The compound-lens eyes of Strepsiptera and the scanning eyes of Sunburst Diving Beetle larvae

Maksimovic, Srdjan January 2010 (has links)
No description available.
36

Identifikation und funktionelle Analyse von Xdach1 und Xeya3 als morphogenetische Faktoren der Kopfentwicklung von Xenopus laevis / Identification and functional analysis of Xdach1 and Xeya3 as morphogenetic factors of head development in Xenopus laevis

Kriebel, Martin 26 January 2005 (has links)
No description available.
37

Μοριακή ανίχνευση και τυποποίηση αδενοϊνών από ασθενείς με επιπεφυκίτιδα / Molecular detection and typing of adenoviruses from patients with conjunctivitis

Μπαλασοπούλου, Αγγελική 02 April 2014 (has links)
Η επιπεφυκίτιδα (φλεγμονή του επιπεφυκότα) είναι η πιο συχνή ασθένεια των οφθαλμών, η οποία εκδηλώνεται σε παγκόσμια κλίμακα με τη μορφή σποραδικών κρουσμάτων ή επιδημίας. Μπορεί να είναι λοιμώδους (βακτήρια, ιοί, παράσιτα) ή μη λοιμώδους αιτιολογίας. Η κύρια αιτία της οξείας ιογενούς αιτιολογίας επιπεφυκίτιδας είναι οι αδενοϊοί. Περίπου το 15- 70% του συνόλου των κρουσμάτων της επιπεφυκίτιδας οφείλονται στους αδενοϊούς. Σκοπός της μελέτης είναι η χρήση επιδημιολογικών δεδομένων προκειμένου να πραγματοποιηθεί επιδημιολογική παρακολούθηση των κρουσμάτων επιπεφυκίτιδας στο Πανεπιστημιακό Γενικό Νοσοκομείο Πατρών (ΠΓΝΠ) από ασθενείς οι οποίοι επισκέφθηκαν την οφθαλμιατρική κλινική και τα εξωτερικά ιατρεία του νοσοκομείου τη χρονική περίοδο 2 Ιανουαρίου – 29 Ιουλίου 2012 (εβδομάδες 1- 30), ο καθορισμός της συχνότητας της ιογενούς αιτιολογίας επιπεφυκίτιδας και ο εντοπισμός πιθανής ύπαρξης επιδημίας. Ταυτόχρονα, πραγματοποιήθηκε μοριακή ανίχνευση και τυποποίηση αδενοϊών από ασθενείς με κλινική εικόνα ιογενούς επιπεφυκίτιδας το χρονικό διάστημα μεταξύ 27 Φεβρουαρίου και 17 Ιουνίου. Όλα τα κρούσματα καταγράφηκαν από τα ιατρικά αρχεία του ΠΓΝΠ για το χρονικό διάστημα Ιανουαρίου- Ιουλίου του 2012 και για το ίδιο χρονικό διάστημα το προηγούμενο έτος (2011). Καταγράφηκαν 231 κρούσματα επιπεφυκίτιδας (47,1% άνδρες και 52,8% γυναίκες), από τα οποία τα 205 ήταν ιογενούς αιτιολογίας, τα 4 βακτηριογενούς αιτιολογίας και 22 ήταν απροσδιόριστης αιτιολογίας από τους ιατρούς. Για την ίδια χρονική περίοδο το προηγούμενο έτος (2011), σύμφωνα με τα αρχεία του ΠΓΝΠ καταγράφηκε ένα σύνολο από 156 κρούσματα επιπεφυκίδας (38,5% άνδρες και 61,5% γυναίκες), από τα οποία τα 135 ήταν ιογενούς αιτιολογίας, τα 3 βακτηριογενούς αιτιολογίας και 18 ήταν απροσδιόριστης αιτιολογίας. Ο αριθμός κρουσμάτων επιπεφυκίτιδας τους δυο πρώτους μήνες καθώς και τον Ιούλιο του 2012 ήταν στα ίδια επίπεδα με τους αντίστοιχους μήνες το 2011 και παρατηρείται επιδημία που πραγματοποιήθηκε μεταξύ Μαρτίου- Ιουνίου 2012. Οι ασθενείς κατανέμονταν σε όλες τις ηλικίες και στα δυο φύλα. Το χρονικό διάστημα μεταξύ 27 Φλεβάρη- 17 Ιουνίου του 2012 (εβδομάδες 9- 24), 48 επιχρίσματα επιπεφυκότα ασθενών με κλινική εικόνα αδενικής επιπεφυκίτιδας συλλέχθηκαν από τους ιατρούς του ΠΓΠΝ και μεταφέρθηκαν υπό κατάλληλες συνθήκες στο εργαστήριο Υγιεινής της Ιατρικής Σχολής του Πανεπιστημίου Πατρών. Ταυτόχρονα συμπληρώθηκε από τους ιδίους ερωτηματολόγιο με δημογραφικά και κλινικά στοιχεία. Το DNA του ιού απομονώθηκε με Qiagen και ενισχύθηκε με nested PCR. Τα θετικά αποτελέσματα επιβεβαιώθηκαν με αλληλούχιση του PCR προϊόντος. Για τον προσδιορισμό της συγγένειας μεταξύ των διαφόρων απομονωμένων αλληλουχιών του DNA, φυλογενετική ανάλυση πραγματοποιήθηκε. Από το σύνολο των δειγμάτων που αναλύθηκαν με μοριακές τεχνικές, DNA αδενοϊού ανιχνεύθηκε σε 40 δείγματα (83%). Στα σαράντα θετικά δείγματα καθορίστηκε η αλληλουχία του DNA τους, από τα οποία τα 29 (72,5%) προσδιορίστηκαν ως τύπος HAdV17 και τα 5 (12,5%) ως τύπος HAdV-54. Σε 6 θετικά δείγματα (15%) ο τύπος του ιού δεν προσδιορίστηκε. Τέλος, με τη βοήθεια των μοριακών τεχνικών προκύπτει το συμπέρασμα ότι το στέλεχος αδενοϊού 17 (Αd 17) είναι η αιτία της εμφάνισης επιδημίας μεταξύ Μαρτίου- Ιουνίου 2012. Η έρευνα αυτή είναι από τις λίγες πιυ έχουν πραγματοποιηθεί στον Ελλαδικό χώρο σε κρούσματα επιπεφυκίτιδας με αποτέλεσμα να εμπλουτίζει τα φτωχά επιδημιολογικά και μοριακά δεδομένα για την συγκεκριμένη ασθένεια και το συγκεκριμένο τύπο ιών. Παράλληλα μέσω της έρευνας υπογραμμίζεται η ανάγκη για εθνικό σύστημα επιτήρησης της επιπεφυκίτιδας. / Conjunctivitis (inflammation of the conjunctiva) is the most common eye disease that occurs worldwide in both sporadic and epidemic form. There are infectious conjunctivitis, which is caused by a variety of microorganisms (such as bacteria, viruses and parasites) and noninfectious conjunctivitis, which is caused by an allergic reaction. The leading cause of acute viral conjunctivitis in clinical practice includes human adenoviruses (HAdVs). About 15- 70% of all conjunctivitis cases worldwide are associated with AdVs. The aim of the study is the performance of epidemiological surveillance of cases of conjunctivitis using epidemiological data from patients who visited the ophthalmic clinic and the outpatient ophthalmic department of the University General Hospital of Patras (UGHP) in the period from January 2nd to July 29th in 2011 and 2012 (weeks 1st-30th), in order to determine the frequency of viral conjunctivitis and to determine a potential epidemic. An additional task of the study is the molecular detection and typing of adenoviruses for cases of patients with clinical viral conjunctivitis in the period from February 27th to June 17th 2012. All conjunctivitis cases referred to UGHP in the period between January and July 2012 as well as between January and July 2011 were ascertained using medical records. 231 conjunctivitis cases were reported (47.1% male and 52.8% female), in which 205 were virological conjunctivitis, 4 bacteriological conjunctivitis and 22 were undefined conjunctivitis. For the same period the previous year (2011), according to the records of UGHP recorded a total of 156 conjunctivitis cases (38.5% male and 61.5% female), of which 135 were of viral origin, 3 bacteriogenic orogin and 18 were undetermined etiology. The number of conjunctivitis cases in the first two months and in July 2012 was at the same level as the corresponding period in 2011 and there is an epidemic that took place between March and June 2012. Patients were allocated to all age groups and both sexes. In the period from February 27th ,2012 to June 17th , 2012 (weeks 9th – 24th), 48 conjunctival swabs were collected from cases which were clinically suspected of having adenoviral conjunctivitis and transported under appropriate conditions to the laboratory of Hygiene, Medical School, University of Patras. At the same time, the patients were asked to answer a structured questionnaire with demographic and clinical data. The viral DNA was isolated with Qiagen and amplified by nested PCR. The positive results were confirmed by sequencing the PCR product. To determine the relatedness between the different isolated sequences, a phylogenetic analysis was constructed. Of the total samples, which were analyzed with molecular techniques, adenovirus DNA was detected in 40 samples (83%). Of the positive samples which were confirmed by sequencing, 29 samples (72.5%) were typed as AdV17 and 5 samples (12.5%) as AdV54. For 6 positive samples (15%) the serotype was not determined. Finally, it was concluded that the strain Adenovirus 17 (Ad 17) was the cause of the epidemic between March and June 2012. There are poor epidemiological and molecular data for this particular disease in Greece. This study is one of the very few on conjunctivitis determination in Greece. This research underscores the need for a national surveillance system for conjunctivis outbreaks.
38

A Holistic Design Concept For Eyes-Free Mobile Interfaces

Dicke, Christina January 2012 (has links)
This thesis presents a series of studies to explore and understand the design of eyes-free interfaces for mobile devices. The motivation is to devise a holistic design concept that is based on the WIMP paradigm and is adapted to the requirements of mobile user interaction. It is proposed that audio is a very efficient and effective modality for use in an eyes-free mobile interface. Methods to transfer the WIMP paradigm to eyes-free interfaces are proposed and evaluated. Guidelines for the implementation of the paradigm are given and – by means of an example – a holistic design concept is proposed. This thesis begins with an introduction to and critical reflection of re- currently important themes and research methods from the disciplines of psychoacoustics, psychology, and presence research. An overview of related work is given, paying particular attention to the use of interface metaphors in mobile eyes-free interfaces. The notion of distance is discussed as a method to prioritise, structure, and manage attention in eyes-free interfaces. Practical issues arising from sources becoming inaudible with increasing distance can be addressed by proposing a method modeled on echo location. This method was compared to verbally coded distance information and proved useful for identifying the closest of several objects, while verbally coded distance infor- mation was found to be more efficient for identifying the precise distance of an object. The knowledge gained from the study can contribute to improv- ing other applications, such as GPS based navigation. Furthermore, the issue of gaining an overview of accessible objects by means of sound was exam- ined. The results showed that a minimum of 200 ms between adjacent sound samples should be adhered to. Based on these findings, both earcons and synthesized speech are recommendable, although speech has the advantage of being more flexible and easier to learn. Monophonic reproduction yields comparable results to spatial reproduction. However, spatial reproduction has the additional benefit of indicating an item’s position. These results are transferable and generally relevant for the use of audio in HCI. Tactile interaction techniques were explored as a means to interact with an auditory interface and were found to be both effective and enjoyable. One of the more general observations was that 2D and 3D gestures were intuitively used by participants, who transferred their knowledge of established gestures to auditory interfaces. It was also found that participants often used 2D ges- tures to select an item and proceeded to manipulate it with a 3D gesture. The results suggest the use of a small gesture set with reversible gestures for do/undo-type actions, which was further explored in a follow up study. It could be shown that simple 3D gestures are a viable way of manipulating spatialized sound sources in a complex 3D auditory display. While the main contribution of this thesis lies in the area of HCI, pre- viously unresearched issues from adjacent disciplines that impact the user experience of auditory interfaces have been addressed. It was found that regular, predictable movement patterns in 3D audio spaces cause symptoms of simulator sickness. However, these were found to be minor and only oc- curred under extreme conditions. Additionally, the influence of the audio reproduction method on the perception of presence, social presence, and realism was examined. It was found that both stereophonic and binaural reproduction have advantages over monophonic sound reproduction: stereo- phonic sound increases the perception of social presence while binaural sound increases the feeling of being present in a virtual environment. The results are important contributions insofar as one of the main applications of mobile devices is voice based communication; it is reasonable to assume that there will be an increase in real-time voice based social and cooperative networking applications. This thesis concludes with a conceptual design of a system called “Foogue”, which uses the results of the previous experiments as the basis of an eyes-free interface that utilizes spatial audio and gesture input.
39

Through My Eyes

Conklin, Candace B. 01 January 2006 (has links)
I am the one my friends call the creepy one. My art is not pretty or happy. It is an expression of my inner feelings and thoughts. I don't make pretty pictures because I find them void of true emotional substance. I developed my point of view when I photographed my eyes, which have become a consistent theme in my work. Eyes are the window to the soul and the key to my inner emotions. I have since expanded my work to include other images. I continue to seek ways to help my viewers experience my work both emotionally and visually. I want them to see the world through my eyes.
40

Impact de la saillance cognitive et émotionnelle sur l'exploration visuelle dans la schizophrénie / Impact of the cognitive and emotional salience on visual exploration in schizophrenia

Grandgenèvre, Pierre 07 September 2015 (has links)
Les troubles cognitives regroupent un ensemble hétérogène d’altérations décrites dans la schizophrénie. Parmi elles, il a été montré que les patients présentent des difficultés à distinguer des informations pertinentes parmi des distracteurs ou encore qu’ils sont particulièrement attirés par l’apparition d’une information soudaine même si celle-ci est non pertinente à la compréhension de la scène. Nos travaux ont pour objectif de préciser ces déficits cognitifs, en se rapprochant des conditions naturelles d’exploration visuelle.L’étude des fixations oculaires permet de mettre en évidence des stratégies d’exploration visuelle et d’évaluer l’impact de la saillance des stimuli sur cette exploration. La saillance se définit comme l’émergence d’une forme sur un fond, et comprend la saillance cognitive (pertinence de l’objet), saillance visuelle (caractéristiques physiques) ou saillance émotionnelle. Le paradigme de cécité au changement est défini comme la surprenante difficulté à détecter un changement lorsque celui-ci survient lors d’une interruption visuelle tel un mouvement de l’oeil. Ce paradigme a pour avantage de permettre de se rapprocher des conditions écologiques d’exploration en utilisant des stimuli en 3D. Plusieurs études ont évalué les facteurs influençant la détection des objets changés avec ce paradigme. Ainsi, l’intérêt de l’objet à la compréhension de la scène, le caractère incongru de l’objet, la couleur, la forme ou la taille de l’objet sont des caractéristiques favorisant la détection du changement.Nos premiers travaux ont consisté en la réalisation de deux études en population saine testant l’influence de deux facteurs sur la détection des changements : l’amplitude des changements et le charge émotionnelle de l’objet changé.Notre première étude a montré que plus la scène contient de changements, plus la détection d’au moins un changement est rapide et précise.Notre seconde étude a montré que la charge émotionnelle portée par les objets changés influençait leur détection. En effet les objets dits émotionnels sont mieux détectés que les objets dits neutres.Nos seconds travaux se sont focalisés sur l’exploration visuelle de patients atteints de schizophrénie comparés à des sujets sains lors de la présentation de scènes de la vie quotidienne. Un paradigme de cécité au changement comprenant des changements non pertinents à la compréhension de la scène, testant ainsi l’impact de la saillance cognitive, a été utilisé. Les variables enregistrées ont été les temps de réponse moteur et des données d’oculomotricité (temps avant la première fixation en zone de changement). Nos résultats montrent une dissociation entre des réponses implicites et explicites : les yeux des patients se fixent plus rapidement sur les changements alors qu’ils rapportent les changements plus lentement que les sujets sains.Enfin dans notre troisième étude, nous avons comparé l’effet de l’apparition soudaine d’une information visuelle à caractère neutre avec l’apparition soudaine d’une information visuelle à caractère émotionnelle en utilisant une tâche écologique de cécité au changement chez des patients atteints de schizophrénie comparés à des sujets sains.Les résultats montrent que la charge émotionnelle portée par les objets changés favorise leur détection uniquement pour les sujets sains.Nous confirmons la sensibilité à l’apparition soudaine d’une information visuelle grâce à un paradigme qui mesure de meilleures performances pour les patients ce qui réduit les effets d’un déficit attentionnel non spécifique. Par ailleurs, les meilleures performances de détection disparaissent dès qu’intervient une charge émotionnelle soulignant les difficultés du traitement des émotions dans la schizophrénie. La surprenante dissociation entre les réponses motrices et oculomotrices pourrait être interprétée comme un déficit d’accès à la conscience perceptive dans la schizophrénie et ainsi ouvrir la voie à des pistes thérapeutiques. / Cognitive impairment includes a heterogeneous set of disorders found in patients with schizophrenia. Among them, patients exhibit clear disadvantages in filtering relevant information in a flow of distractors or the attention of these patients can be captured by the sudden irruption of visual information, even if irrelevant to understand the scene. The objective of our research is to specify these cognitive disorders by approaching the ecological conditions of visual exploration.The study of eye fixations allows to highlight visual exploration strategies or to assess the impact of the stimuli salience on the visual exploration. The salience is defined as the emergence of a form on a background. We can observed a cognitive salience (the object’s relevance), a physical salience (the physical characteristics) or emotional salience. The paradigm of change blindness is defined by the failure to notice changes in scene when these changes occur following brief disruptions, such as eye movements. This paradigm exhibits the advantage to approach natural conditions of exploration using 3D stimuli. Several studies have evaluated different factors having an impact on the detection of changed object with this paradigm. Therefore, the interest of the main object to the comprehension of the scene, the incongruous objects, color, shape or size of the object are characteristics promoting the detection of change.Our initial task consists of the conduct of two distinct studies with healthy subjects testing the influence of two factors on the detection of change: the magnitude of change and the emotional aspect of changed objects. Our first study showed that the more the scene contains changes, the faster, the more efficient we detect at least one change. Our second study showed that the emotional aspect of changed objects impacted their detection. Indeed emotional objects are best detected that neutral objects.Our second study has focused on the visual exploration of patients with schizophrenia compared to healthy subjects during the presentation of scenes of everyday life. We used a paradigm of change blindness including irrelevant changes in the understanding of the scene. This paradigm allows to test the cognitive salience. The main recorded variables were the motor response time and eye tracking data (the latency of the first fixation in a region of interest). Our results exhibited a striking dissociation between the explicit and implicit responses: the patients\\\\\\\' eyes shifted faster toward the changes despite explicitly reporting the change more slowly than the healthy subjects.Finally in our third study, we compared the effect of the sudden irruption of an emotional visual information with the sudden irruption of a neutral visual information using an ecological task of change blindness. We compared patients with schizophrenia to healthy subjects. Results show that changes in emotional objects are better detected than changes in neutral objects only for the healthy subjects.We confirmed the patients\\\\\\\' sensitivity to the sudden onset of visual information with a paradigm that measured a better performance in the patients, which thereby reduced the effects of a non-specific attentional deficit. Moreover, the better detection performances disappear when changes lay an emotional influence, highlighting the difficulties of emotional processing in schizophrenia. Finally, the surprising dissociation between implicit and explicit responses in schizophrenia can be interpreted as a deficit of access to conscious perception, which could be of interest to various therapeutic techniques.

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