Thèses : « Contatto visivo »

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Bellini, Luciano Porto. « Estudo comparativo entre o telescópio com lente de contato e o telescópio convencional em pacientes com baixa visão ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/17787.

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Objetivos: comparar o telescópio com lente de contato (TLC) com o telescópio convencional (TC) em pacientes com degeneração macular relacionada à idade (DMRI) e baixa visão, com respeito a: acuidade visual (AV), campo de visão (CV), satisfação do paciente com a visão oferecida pelo telescópio (SV), dificuldade de uso do telescópio (DU) e satisfação do paciente com o aspecto estético do telescópio (SE). Materiais e Métodos: Em ensaio clínico randomizado mascarado, foram incluídos 12 pacientes com DMRI e baixa visão, formando 2 grupos de 6 pacientes cada: grupo 1 (uso de TLC) e grupo 2 (uso de TC). Os telescópios usados no estudo foram padronizados para que tivessem a mesma magnificação (2,8x). A AV e o CV foram aferidos antes e durante o uso do telescópio, enquanto a SV, a DU e a SE foram obtidas após a intervenção. Resultados: Não houve diferenças entre os grupos na linha de base. Os dois telescópios demonstraram melhora da AV em relação à linha de base (P=0,002 com o TLC e P<0,001 com o TC) e não houve diferença entre os grupos a este respeito. O CV foi reduzido em 15° com o TLC (P<0.001) e em 54.3° com o TC (P<0.001), em comparação com a linha de base, e tais diferenças também foram significativas entre os grupos durante a intervenção (P<0.001). Os escores de SV foram semelhantes entre os grupos testados. Já os escores de SE, foram maiores com o TLC (P<0.001), assim como os de DU (P=0.003), em relação ao TC. Conclusões: Os dois telescópios promoveram melhora semelhante da AV em pacientes com DMRI e baixa visão, mas o TLC acarretou menor perda de CV em relação ao TC. A SE foi maior com o TLC, mas a DU também foi maior com o TLC, em relação ao TC.
Purpose: To compare the conventional telescope (CT) with the contact lens telescope (CLT) in patients with age-related macular degeneration (AMD) and low-vision, with respect to visual acuity (VA), visual field (VF), patient satisfaction with the vision provided by the telescope (VS), telescope use difficulties (UD) and patient satisfaction with the cosmetic appearance of the telescope (CS). Methods: In a masked randomized clinical trial, 12 patients with AMD and low-vision were enrolled in 2 groups with 6 patients each: group 1 (CLT use) and group 2. (CT use) The telescopes used in this study were standardized to have the same magnification power. (2.8x) Visual field and VA were obtained before and during the telescope use, while VS, UD and CS were obtained after the telescope use. Results: There were no significant differences between groups at baseline. Both groups achieved VA improvement with telescopes compared to baseline (P=0.002 in CLT group and P<0.001 in CT group) and there were no significant differences between groups in this regard. Visual field was reduced by 15° in CLT group (P<0.001) and by 54.3° in CT group (P<0.001) compared to baseline, and VF differences between groups were also significant during telescope use. (P<0.001) Scores observed in both groups were similar in regard to VS. Telescope use difficulties were significant higher in CLT group (P=0.003) as well as CS scores (P<0.001) compared to CT group. Conclusions: Both telescopes provide similar improvement in VA in AMD patients with low-vision, but CLT caused less VF reduction than CT use. Patient satisfaction with the cosmetic appearance of the telescope was higher in CLT group, but UD was also higher in this group compared to CT group.

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Irwin, Kenneth M. « Wilderness visitor response to ranger educational contacts at trailheads ». Thesis, Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/91123.

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The use of wilderness rangers to educate visitors on Without-A-Trace camping and wilderness ethics at trailheads is a common management practice, but little is known about how such contacts affect the visitors' wilderness experiences. The purpose of this study was to determine whether Shining Rock Wilderness visitors perceived trailhead contacts as light-handed or heavy-handed and the factors which caused them to perceive the contact the way they did. It also determined whether or not the visitors felt that site conditions in the wilderness were getting better or worse. On-site questionnaires were administered to visitors as they left the area. A majority felt the trailhead contact was a light-handed way to manage wilderness use. The visitors felt that the contact did not take away their freedom to choose how, when or where to recreate. The rangers were perceived as friendly, knowledgeable, and non-authoritarian. The condition of Shining Rock Wilderness was perceived to be relatively free of site impacts. There were no significant differences in the visitors' perceptions of the ranger or the contact due to the sex or experience of the ranger or the sex, age, or experience of the visitors. Implications for wilderness management and research are discussed.
M.S.

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Xu, Yan. « Non-contact vision-based deformation monitoring on bridge structures ». Thesis, University of Exeter, 2018. http://hdl.handle.net/10871/34643.

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Information on deformation is an important metric for bridge condition and performance assessment, e.g. identifying abnormal events, calibrating bridge models and estimating load carrying capacities, etc. However, accurate measurement of bridge deformation, especially for long-span bridges remains as a challenging task. The major aim of this research is to develop practical and cost-effective techniques for accurate deformation monitoring on bridge structures. Vision-based systems are taken as the study focus due to a few reasons: low cost, easy installation, desired sample rates, remote and distributed sensing, etc. This research proposes an custom-developed vision-based system for bridge deformation monitoring. The system supports either consumer-grade or professional cameras and incorporates four advanced video tracking methods to adapt to different test situations. The sensing accuracy is firstly quantified in laboratory conditions. The working performance in field testing is evaluated on one short-span and one long-span bridge examples considering several influential factors i.e. long-range sensing, low-contrast target patterns, pattern changes and lighting changes. Through case studies, some suggestions about tracking method selection are summarised for field testing. Possible limitations of vision-based systems are illustrated as well. To overcome observed limitations of vision-based systems, this research further proposes a mixed system combining cameras with accelerometers for accurate deformation measurement. To integrate displacement with acceleration data autonomously, a novel data fusion method based on Kalman filter and maximum likelihood estimation is proposed. Through field test validation, the method is effective for improving displacement accuracy and widening frequency bandwidth. The mixed system based on data fusion is implemented on field testing of a railway bridge considering undesired test conditions (e.g. low-contrast target patterns and camera shake). Analysis results indicate that the system offers higher accuracy than using a camera alone and is viable for bridge influence line estimation. With considerable accuracy and resolution in time and frequency domains, the potential of vision-based measurement for vibration monitoring is investigated. The proposed vision-based system is applied on a cable-stayed footbridge for deck deformation and cable vibration measurement under pedestrian loading. Analysis results indicate that the measured data enables accurate estimation of modal frequencies and could be used to investigate variations of modal frequencies under varying pedestrian loads. The vision-based system in this application is used for multi-point vibration measurement and provides results comparable to those obtained using an array of accelerometers.

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Collumeau, Jean-François. « Commande sans contact d'éclairage opératoire par méthodes de vision informatique ». Thesis, Orléans, 2014. http://www.theses.fr/2014ORLE2001.

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De nos jours, le maintien de l'asepsie dans la salle d'opération est vital pour la limitation de la transmission d'infections nosocomiales au patient lors de l'opération. Des mesures d'asepsie drastiques ont pour but de préserver la zone stérile de tout agent infectieux.Elles interdisent actuellement au chirurgien d'interagir avec les équipements non-stériles du bloc.Le chirurgien opérant souhaiterait cependant disposer d'un contrôle direct sur certains équipements spécifiques du bloc dans des situations données sans enfreindre ces mesures.Les travaux présentés dans cette thèse concernent le développement d'une Interface Homme-Machine permettant la commande gestuelle sans contact, et donc sans transmission d'agents infectieux, de tels équipements.Dans la continuité des travaux existants dans la littérature, une chaîne de traitement basée sur des techniques de vision informatique et un prototype de caméra portée par l'utilisateur ont ainsi été développés pour atteindre ces objectifs. Ce document présente les études comparatives menées sur des algorithmes issus de la littérature afin de sélectionner les plus aptes à être employés dans la chaîne logicielle. Un descripteur géométrique dédié aux mains est introduit, et des approches coopératives sont investiguées sur les étapes de localisation de la main et de classification de la posture prise.Les performances de la chaîne de traitement ainsi créée sont évaluées dans différentes situations à l'aide de bases d'images et de vidéos extensives acquises dans des conditions proches de celles du bloc opératoire, ainsi que sur des images synthétiques réalisées sur un modèle virtuel de main créé ad hoc.Un démonstrateur composé de la chaîne de traitement développée et d'un prototype de caméra frontale permet, associé à une simulation de bras-support d'éclairage opératoire, d'illustrer les possibilités ouvertes par le système développé au cours de cette thèse
Asepsis preservation in operating rooms is nowadays compulsory for avoiding the spread of hospital-acquired diseases to patients during surgeries. Drastic asepsis measures aim at preserving the sterile area of the operating room from infective agents.These measures forbid surgeons from interacting with non-sterile devices. Surgeons wish nonetheless having direct control over some of these devices.The works presented in this thesis relate to the development of a Human-Computer Interface enabling remote, hence without transmission of infective agents, non-contact control over such devices.Following on from previous authors' works in the literature, an image processing chain based on computer vision techniques and a wearable camera prototype have been developed in order to achieve these goals.This document presents the comparative studies led with algorithms issued from the literature with the aim of selecting the most suitable for using in the processing chain. A dedicated geometry-based hand descriptor is introduced, and cooperative approaches are investigated in relation with the hand localization and posture classification steps.The performance achieved by the processing chain in various situations are quantified using extensive picture and video databases acquired in conditions close to those of the operating room. Synthetic pictures created using an ad hoc virtual model of the hand are used as well for this evaluation.A demonstrator composed of the developed processing chain, a wearable camera prototype and a surgical lighting arm simulator enables the illustration of the possiblities offered by the system developed during this thesis

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Pham, Tu-Hoa. « Contact force sensing from motion tracking ». Thesis, Montpellier, 2016. http://www.theses.fr/2016MONTT287/document.

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Le sens du toucher joue un rôle fondamental dans la façon dont nous percevons notre environnement, nous déplaçons, et interagissons délibérément avec d'autres objets ou êtres vivants. Ainsi, les forces de contact informent à la fois sur l'action réalisée et sa motivation. Néanmoins, l'utilisation de capteurs de force traditionnels est coûteuse, lourde, et intrusive. Dans cette thèse, nous examinons la perception haptique par la capture de mouvement. Ce problème est difficile du fait qu'un mouvement donné peut généralement être causé par une infinité de distributions de forces possibles, en multi-contact. Dans ce type de situations, l'optimisation sous contraintes physiques seule ne permet que de calculer des distributions de forces plausibles, plutôt que fidèles à celles appliquées en réalité. D'un autre côté, les méthodes d'apprentissage de type `boîte noire' pour la modélisation de structures cinématiquement et dynamiquement complexes sont sujettes à des limitations en termes de capacité de généralisation. Nous proposons une formulation du problème de la distribution de forces exploitant ces deux approches ensemble plutôt que séparément. Nous capturons ainsi la variabilité dans la façon dont on contrôle instinctivement les forces de contact tout en nous assurant de leur compatibilité avec le mouvement observé. Nous présentons notre approche à la fois pour la manipulation et les interactions corps complet avec l'environnement. Nous validons systématiquement nos résultats avec des mesures de référence et fournissons des données exhausives pour encourager et évaluer les travaux futurs sur ce nouveau sujet
The human sense of touch is of fundamental importance in the way we perceive our environment, move ourselves, and purposefully interact with other objects or beings. Thus, contact forces are informative on both the realized task and the underlying intent. However, monitoring them with force transducers is a costly, cumbersome and intrusive process. In this thesis, we investigate the capture of haptic information from motion tracking. This is a challenging problem, as a given motion can generally be caused by an infinity of possible force distributions in multi-contact. In such scenarios, physics-based optimization alone may only capture force distributions that are physically compatible with a given motion, rather than those really applied. In contrast, machine learning techniques for the black-box modelling of kinematically and dynamically complex structures are often prone to generalization issues. We propose a formulation of the force distribution problem utilizing both approaches jointly rather than separately. We thus capture the variability in the way humans instinctively regulate contact forces while also ensuring their compatibility with the observed motion. We present our approach on both manipulation and whole-body interaction with the environment. We consistently back our findings with ground-truth measurements and provide extensive datasets to encourage and serve as benchmarks for future research on this new topic

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Rueff, Erin M. « Contact Lens Discomfort, Vision Correction Preferences, and Accommodative Treatment in Presbyopic and Non-Presbyopic Contact Lens Wearers ». The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1529583462118691.

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Kobeissi, Habib. « Théorie de la vision et du contact entre objets linéaires et parallèles du plan ». Paris, EHESS, 1987. http://www.theses.fr/1987EHES0070.

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Ce travail consiste a creer une relation de contact, entre des segments paralleles du plan permettant un ensemble d'operations interactives sur des schemas. -etude de la relation de contact et son graphe. -methodes de construction de la relation et les structures de donnees utilisees. -inserer, supprimer ou diviser un segment a l'aide de la relation construite. -cette relation permet la translation d'un segment pour venir en contact d'un autre en entrainant, au besoin, la translation d'autres segments sans creer de chevauchement. -on peut compacter un schema a l'aide de la relation. Toutes ces operations interactives sont effectuees avec le soucis d'affiner au maximum la complexite de leurs algorithmes respectifs.

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Scarl, Daniel L. « Eye contact perception at distances up to six meters ». PDXScholar, 1985. https://pdxscholar.library.pdx.edu/open_access_etds/3693.

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Common experience suggests that most people can tell whether they are being looked at by another person who is about 8 m away. However, the results of past experiments, which used distances of no more than about 3 m, have implied that this cannot be done if the person looked at (Receiver) judges only by the iris-sclera configuration of the person looking (Sender). This is true even if eye contact is defined simply as identifying on-face gazes (FGs). It has been suggested that in everyday experience eye contact is accompanied by cues other than iris position, and that these non-iris-position (NIP) cues to Receiver account for recognition at longer distances. The hypotheses of the present experiment are that FGs can be identified at considerably more than 3 m, without NIP cues: and that this happens because as features of Sender's lower face fall within Receiver's central vision at longer distances, Receiver is able to use them for triangulating the position of Sender's irises.

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Achor, Sam Ndu. « Family visits or contact to dementia elderly at long term care facilities ». CSUSB ScholarWorks, 2000. https://scholarworks.lib.csusb.edu/etd-project/1581.

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Almada, Isabela, Gérson Tontini et Universidade Regional de Blumenau Programa de Pós-Graduação em Administração. « Identificação de atributos criticos de satisfação em serviços de arquitetura :visão do cliente vs visão do arquiteto / ». reponame:Biblioteca Digital de Teses e Dissertações FURB, 2008. http://www.bc.furb.br/docs/DS/2008/332750_1_1.pdf.

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Bernardet, Laurent. « Diffusion et holographie de la peau en lumière blanche : recherche de méthodes pertinentes pour une caractérisation sans contact ». Besançon, 1994. http://www.theses.fr/1994BESA0427.

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Ce travail a pour objectif de déterminer les conditions théoriques et les dispositifs expérimentaux donnant accès au relief cutané (les rides en particulier), in vivo et sans contact, au moyen d'un outil intégré, portable et utilisable en environnement de test cosméto-clinique. Pour cela, le plan est structuré en trois parties : 1. L'étude de l'influence des coefficients optiques de la peau sur son aspect visuel et photographique et sur la qualité des mesures de réflectance. Une modélisation nouvelle de la réponse de la peau, grâce à la convolution de la figure d'éclairement en surface par une "Réponse Impulsionnelle de Rétrodiffusion", a été proposée. Cette RIR dépend à la fois des coefficients d'absorption et de diffusion dans le volume du matériau. 2. L'étude des conditions d'application aux rides des méthodes optiques d'acquisition du relief. En particulier l'utilisation des techniques de projection de franges a été validée sur des moulages de peau, ce qui permet d'accélérer considérablement les temps de traitement par rapport aux méthodes habituelles à balayage. . .

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Whatham, Andrew. « The effect of optical or pharmacological perturbation of focus on refractive development and ocular growth in the common marmoset ». Thesis, University of Oxford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312637.

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Keay, Lisa Jane Optometry &amp Vision Science Faculty of Science UNSW. « Public health impact of contact lens related microbial keratitis ». Awarded by:University of New South Wales. School of Optometry and Vision Science, 2006. http://handle.unsw.edu.au/1959.4/26307.

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This thesis describes the impact of contact lens-related microbial keratitis in terms of incidence and severity. Disease outcome is defined by visual outcome, costs to the healthcare system, costs to the individual and duration of disease. A successful 12-month surveillance study was conducted of the populations of Australia and New Zealand to detect all cases of contact lens-related microbial keratitis. A random telephone survey of 32,000 households in Australia and 7,500 in New Zealand accurately determined the level of use of various contact lenses in the community. The impact of new contact lens types: silicone hydrogels and daily disposables were investigated. Increased risk persisted in overnight wear with silicone hydrogel materials. Microbial keratitis associated with silicone hydrogel materials had slightly shorter disease duration however other factors had a stronger influence on severity. Rigid gas permeable and frequent replacement soft lenses when used for daily wear constitute the lowest risk. Cost analysis was developed in a hospital case series of microbial keratitis. This analysis was applied in the surveillance study including cases managed in the private health care sector. Disease duration and associated costs are novel indices of severity for contact lens-related disease. The most dramatic effects on disease severity were seen with the type of organism involved. Keratitis attributed to environmental organisms (Gram-negative bacteria, Acanthamoeba, fungi and Nocardia species) were 10x more likely to cause loss of visual acuity, had longer duration of symptoms and incurred higher costs. Importantly, delays in receiving treatment increased disease duration and associated costs. Greater awareness of the need for specialist healthcare is indicated amongst health care providers and contact lens wearers. The hypothesis that overnight wear in silicone hydrogel lenses would not increase the risk of infection has been disproven. This information is of value to practitioners who are responsible for informing contact lens wearers about the risk of contact lens-related infections and should be weighed against the benefits of continuous wear. The identification of factors which contribute to the outcomes of disease will be used in education campaigns amongst health care providers and contact lens wearers to minimise the impact of disease.

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Chu, Byoung Sun. « The impact of presbyopic spectacles and contact lenses on driving performance ». Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/31885/1/Byoung_Chu_Thesis.pdf.

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Presbyopia affects individuals from the age of 45 years onwards, resulting in difficulty in accurately focusing on near objects. There are many optical corrections available including spectacles or contact lenses that are designed to enable presbyopes to see clearly at both far and near distances. However, presbyopic vision corrections also disturb aspects of visual function under certain circumstances. The impact of these changes on activities of daily living such as driving are, however, poorly understood. Therefore, the aim of this study was to determine which aspects of driving performance might be affected by wearing different types of presbyopic vision corrections. In order to achieve this aim, three experiments were undertaken. The first experiment involved administration of a questionnaire to compare the subjective driving difficulties experienced when wearing a range of common presbyopic contact lens and spectacle corrections. The questionnaire was developed and piloted, and included a series of items regarding difficulties experienced while driving under day and night-time conditions. Two hundred and fifty five presbyopic patients responded to the questionnaire and were categorised into five groups, including those wearing no vision correction for driving (n = 50), bifocal spectacles (BIF, n = 54), progressive addition lenses spectacles (PAL, n = 50), monovision (MV, n = 53) and multifocal contact lenses (MTF CL, n = 48). Overall, ratings of satisfaction during daytime driving were relatively high for all correction types. However, MV and MTF CL wearers were significantly less satisfied with aspects of their vision during night-time than daytime driving, particularly with regard to disturbances from glare and haloes. Progressive addition lens wearers noticed more distortion of peripheral vision, while BIF wearers reported more difficulties with tasks requiring changes in focus and those who wore no vision correction for driving reported problems with intermediate and near tasks. Overall, the mean level of satisfaction for daytime driving was quite high for all of the groups (over 80%), with the BIF wearers being the least satisfied with their vision for driving. Conversely, at night, MTF CL wearers expressed the least satisfaction. Research into eye and head movements has become increasingly of interest in driving research as it provides a means of understanding how the driver responds to visual stimuli in traffic. Previous studies have found that wearing PAL can affect eye and head movement performance resulting in slower eye movement velocities and longer times to stabilize the gaze for fixation. These changes in eye and head movement patterns may have implications for driving safety, given that the visual tasks for driving include a range of dynamic search tasks. Therefore, the second study was designed to investigate the influence of different presbyopic corrections on driving-related eye and head movements under standardized laboratory-based conditions. Twenty presbyopes (mean age: 56.1 ± 5.7 years) who had no experience of wearing presbyopic vision corrections, apart from single vision reading spectacles, were recruited. Each participant wore five different types of vision correction: single vision distance lenses (SV), PAL, BIF, MV and MTF CL. For each visual condition, participants were required to view videotape recordings of traffic scenes, track a reference vehicle and identify a series of peripherally presented targets while their eye and head movements were recorded using the faceLAB® eye and head tracking system. Digital numerical display panels were also included as near visual stimuli (simulating the visual displays of a vehicle speedometer and radio). The results demonstrated that the path length of eye movements while viewing and responding to driving-related traffic scenes was significantly longer when wearing BIF and PAL than MV and MTF CL. The path length of head movements was greater with SV, BIF and PAL than MV and MTF CL. Target recognition was less accurate when the near stimulus was located at eccentricities inferiorly and to the left, rather than directly below the primary position of gaze, regardless of vision correction type. The third experiment aimed to investigate the real world driving performance of presbyopes while wearing different vision corrections measured on a closed-road circuit at night-time. Eye movements were recorded using the ASL Mobile Eye, eye tracking system (as the faceLAB® system proved to be impractical for use outside of the laboratory). Eleven participants (mean age: 57.25 ± 5.78 years) were fitted with four types of prescribed vision corrections (SV, PAL, MV and MTF CL). The measures of driving performance on the closed-road circuit included distance to sign recognition, near target recognition, peripheral light-emitting-diode (LED) recognition, low contrast road hazards recognition and avoidance, recognition of all the road signs, time to complete the course, and driving behaviours such as braking, accelerating, and cornering. The results demonstrated that driving performance at night was most affected by MTF CL compared to PAL, resulting in shorter distances to read signs, slower driving speeds, and longer times spent fixating road signs. Monovision resulted in worse performance in the task of distance to read a signs compared to SV and PAL. The SV condition resulted in significantly more errors made in interpreting information from in-vehicle devices, despite spending longer time fixating on these devices. Progressive addition lenses were ranked as the most preferred vision correction, while MTF CL were the least preferred vision correction for night-time driving. This thesis addressed the research question of how presbyopic vision corrections affect driving performance and the results of the three experiments demonstrated that the different types of presbyopic vision corrections (e.g. BIF, PAL, MV and MTF CL) can affect driving performance in different ways. Distance-related driving tasks showed reduced performance with MV and MTF CL, while tasks which involved viewing in-vehicle devices were significantly hampered by wearing SV corrections. Wearing spectacles such as SV, BIF and PAL induced greater eye and head movements in the simulated driving condition, however this did not directly translate to impaired performance on the closed- road circuit tasks. These findings are important for understanding the influence of presbyopic vision corrections on vision under real world driving conditions. They will also assist the eye care practitioner to understand and convey to patients the potential driving difficulties associated with wearing certain types of presbyopic vision corrections and accordingly to support them in the process of matching patients to optical corrections which meet their visual needs.

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Magill, Christine. « Penalising prisoners, penalising families : the difficulties of maintaining contact with prisoners through prison visits ». Thesis, University of Leicester, 2001. http://hdl.handle.net/2381/30120.

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This research considers the difficulties that are encountered when visiting a loved one or relative who is in prison. Early research in this area drew attention to the Prison Service's lack of consideration for families visiting prisons (see Matthews. 1983 1989). Following the Woolf Report (1991) and subsequent reforms, commentators were optimistic that, at last, the Prison Service was starting to address issues relating to prisoners' families. However, much has happened within the prison system since this time - numbers in prison have increased, there has been a renewed emphasis on security, order and control in prison, and a requirement to reduce drug misuse amongst prisoners. The present study reviews the situation in view of these developments. Theoretically, this research draws upon recent feminist work to emerge from North America that focused on the 'hidden' implications of crime control policies for women outside the criminal justice process (see Miller. 1998 Danner. 1998 Massey et al. 1998). Prisoners' families constitute one group with whom this new approach is concerned. This latest feminist endeavour aims to change criminal justice policies and practices so as to lessen the costs to women and children. This aim also formed the rationale for the present study. A multi-method approach was employed. This included a survey of 133 prisons in England and Wales (a response rate of 67% was obtained) and interviews with thirty prison visitors at two prisons. Observational data was also collected at these two prisons. The findings suggest that prisoners' families continue to be ignored by a prison system that treats them as little more than a resource, removed from penal considerations yet entwined into policy when their assistance is required. A number of recommendations for changes to penal policy and practice designed to improve the situation for prisoners' families are proposed.

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Rueff, Erin. « Contact lens induced dry eye and binocular vision disorders : A study of similar symptoms ». The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397167126.

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Matthews, Mark Walter. « A machine vision based non-contact measuring tool for mensuration in industry and manufacturing ». Master's thesis, University of Cape Town, 1994. http://hdl.handle.net/11427/17012.

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Bibliography: leaf 53.
This thesis report discusses the design, implementation and testing of a non-contact measuring tool based on the principle of stereo photogrammetry. The system uses a pair of CCD video cameras and a frame-grabber in a PC to capture the pair of images this requires. The software on the PC then measures the image co-ordinates of points selected by the user and transforms them into space co-ordinates for the points. The transformation requires knowledge of the relative positions and orientations of the cameras. This is found in a calibration stage from images of a calibration frame. The cameras are mounted on a bar, which guarantees that the relative positions and orientations of the cameras remain invariant within certain limits. This makes the system portable.

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Prieto, Flavio Redarce Tanneguy Lepage Richard Boulanger Pierre. « Métrologie assistée par ordinateur apport des capteurs 3D sans contact / ». Villeurbanne : Doc'INSA, 2000. http://docinsa.insa-lyon.fr/these/pont.php?id=prieto.

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Gifford, Kate L. « Binocular visual function in orthokeratology contact lens wear for myopia ». Thesis, Queensland University of Technology, 2018. https://eprints.qut.edu.au/116154/1/Kate_Gifford_Thesis.pdf.

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Orthokeratology (OK) contact lenses have shown propensity for slowing down the worsening of myopia in children and young adults, with only some understanding of the mechanism. This thesis examined eye muscle coordination and focussing in OK contact lens wear; outcomes were consistent with a lower myopia progression risk and improved visual comfort compared to standard spectacles and soft contact lenses. These findings have relevance for patient acceptance, clinical management protocols and understanding OK's optical impact on the visual system of the young myope.

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Prieto, Flavio. « Métrologie assistée par ordinateur : apport des capteurs 3D sans contact ». Lyon, INSA, 1999. http://theses.insa-lyon.fr/publication/1999ISAL0117/these.pdf.

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Ce travail de recherche concerne l'inspection automatique de pièces industrielles à partir du modèle CAO de la pièce et de son image 3D obtenue à l'aide d'un capteur laser de haute précision. Tout d'abord nous déterminons et modélisons les différents paramètres qui influencent la précision du capteur laser lors du processus de numérisation d'une pièce. Ce modèle est utilisé pour générer automatiquement une stratégie d'acquisition pour la numérisation complète et précise d'une surface ou d'une pièce complète. La stratégie d'acquisition consiste en la détermination d'un ensemble de points de vue qui définissent la position spatiale et l'orientation exacte du capteur par rapport à la pièce, ainsi que d'autres paramètres du capteur. Le but de la stratégie de numérisation est d'améliorer l'exactitude des mesures de profondeur afin de pouvoir utiliser ce nuage de points 3D dans des tâches de métrologie. Les contraintes imposées au système sont : la connaissance de la position et de l'orientation initiale de la pièce et de son modèle CAO en format IGES. Il n'y a pas de limitations quant à la géométrie de l'objet à inspecter, par conséquent il est possible de contrôler des pièces avec des surfaces simples ou complexes. Le nuage de points issu de la numérisation d'une pièce est recalé avec son modèle CAO et postérieurement segmenté. La segmentation est réalisée par le calcul de la distance minimale du point 3D aux surfaces du modèle CAO et par la comparaison de propriétés géométriques du point 3D avec son homologue appartenant à la surface. Les résultats de la segmentation sont utilisés pour contrôler les tolérances dimensionnelles et géométriques de la pièce. En utilisant le modèle du bruit, nous avons introduit une valeur de dispersion sur chacun des points 3D acquis par le capteur. Cette valeur de dispersion est présentée comme un facteur de pondération dans les résultats de l'inspection
This work is related with the automatic inspection of manufactured parts by using the CAD model of the part and the cloud of 3D points obtained by the digitization of the part with a range sensor. Initially we determine and model the parameters which influence the accuracy of the range sensor in the digitalization of a part. This model is used to produce automatically a sensing plan in order to acquire completely and precisely the geometry of a surface or of a complete part. A sensing plan consists of a set of viewpoints which defined the exact position and orientation of the camera relative to the part and other digitizatioin parameters. The goal of the sensing plan is to improve the accuracy of the depth measurement in order to be able to use the cloud of 3D points in inspection tasks. The requirements of the system are the exact position and orientation of the part and its CAD model in IGES format. There is no limitation in the geometry of the part to be digitized, hence simple / complex parts can be scanned. After registration between the 3D data and the CAD model, the cloud is segmented. The segmentation is fulfiled by computing the minimal distance from the 3D point to the surfaces (of the CAD model) and comparing some local geometric properties of the 3D point with the closest one on the surfaces. Segementation results are used to check dimensional and geometric tolerances of the part. By using the model of the noise we have introduced a dispersion value on each 3D point acquired by the range sensor. This value of dispersion is presented as a weight factor in the results of the dispersion

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Dugáček, Ján. « Automatizované optické měření kontaktního úhlu kapky ». Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2018. http://www.nusl.cz/ntk/nusl-377330.

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Measurement of surface tension of solids usually requires manual processing of photographs of droplets of liquids with known properties on the measured material's surface, during which the contact angle is manually determined. The objective of this work is to implement an algorithm that can determine these contact angles from photographs and does not require the photographs to be made under specific light conditions. The implementation cannot depend on paid libraries and must be simple to incorporate into existing software.

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Carter, Nakia J., Rick L. Wallace et Kefeng (Maylene) Qiu. « Blending Phone Contacts and Site Visits to Promote Rural Outreach Services : A Randomized Controlled Trial to Assess Usage ». Digital Commons @ East Tennessee State University, 2009. https://dc.etsu.edu/etsu-works/8750.

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Objective: The East Tennessee State University Quillen College of Medicine Library (ETSUQCOML) wanted to determine if the introduction of phone calls to an existing outreach visit increased the usage of the ETSUQCOML’s services. Methods: Eight hospitals and sixteen clinics were chosen to participate. Two site visits were made a month to each participating institution. A total of two phone calls and two emails a month were given to multiple contacts in the hospital or clinic. The hospitals and clinics were randomized to determine which received the phone call intervention. Interlibrary loan statistics and reference search statistics were then analyzed to determine if there was a statistically significant difference. The data were also analyzed to determine if the intervention was more successful in hospitals or clinics. Results: Librarians learned to what degree email and phone calls could be substituted for personal visits in an outreach service as a means of maintaining it and not experiencing a decline in service requests. Conclusions: In today’s economic times, it is important to maintain services to underserved health care providers but to do it in the most cost effective manner. This study has provided helpful data as to the possibility of substituting less expensive contacts such as emails or phone calls for more expensive ones such as face-to-face visits in order to sustain an outreach service. The authors are looking to extend this project to multiple end-points such as six months, nine months, and one year to determine sustainability.

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Alves, Sara Gonçalves. « Suspeita de reativação de toxoplasmose, adaptação de lentes de contacto de silicone-hidrogel tóricas, excesso acomodativo ». Master's thesis, Universidade da Beira Interior, 2013. http://hdl.handle.net/10400.6/1493.

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Este relatório foi realizado como prova final de um período de estágio que decorreu entre 15 de outubro de 2012 e 24 de janeiro de 2013 na Clinica OcularEyeCare, em Aveiro. Tem como principal objetivo a descrição de três casos clínicos que ocorreram durante o estágio sendo um deles um caso com referenciação de patologia ocular, outro um caso de visão binocular e um terceiro de contactologia envolvendo lentes tóricas. Neste relatório é abordado um caso de suspeita de reativação da toxoplasmose, um caso de adaptação de lentes de contacto de silicone-hidrogel tóricas e um caso de excesso acomodativo.

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Giner, Tort Anna. « Optical and visual characterization of multifocal contact lenses and multifocal intraocular lenses ». Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/663449.

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Vision is presented and universally accepted as the most precious of the human senses.lt is structured in three main parts: the optical system {eye), the photo-sensor {eye's retina), and the data processor (brain). If one of them is affected by any disease or dysfunction, vision will be terrible or even nonexistent One of the most common dysfunction is presbyopia.lt i s an age-related disorder that is undergone by all the population s ince their mid-late-40s and it is consists in the loss of the ability to focus near objects (accommodation). A huge number of possible corrections of it can be easily found. On one hand, there are temporary corrections ,as progressive spectacle tenses or multifocal contact tenses. On the other hand, permanent corrections as multifocal i ntraocular lenses, multifocal cornea! ablation, accommodating intraocular tenses, monovision systems, or scleral modifications are also applied to correct presbyopia. Another age-related dysfunction is cataract. Cataract is the opacification of the crystalline fens and decreases the quality of the visual function. Consequently, it is one of the leading visual impairments in adults over 60 years old, affecting the half of the adults aged between 75-85 years old. The only possible solution far cataract is the extraction of the opacified fibers of the crystalline lens and the replacement of them with an intraocular lens by surgery. Due to the fact that all the patients affected by an age-related cataract are also affected by presbyopia it is totally understandable that a number of patients choose mulltifocal introcular lens to substitute their crystalline tenses .This way, only one surgery is needed to salve both age-related dysfunctions. Usually, young presbyopes choose a temporary correction as a first option to correct presbyopia. Some presbyopia corrections are based on the simultaneous vision principie, as, far example, multifocal contact or intraocular lenses. The optical design of these kind of lenses is very complex. Consequently, It is characterization is also difficult When these lenses were launched into the market, it was only possible to characterize optical quality before the implantation or the adaptation of them (characterization in vitro) and the visual quality after the surgery or the clinical adaptation was performed (characterization) .M. present and thanks to the technological advances, different new commercial instruments that are to perform characterization in vivo of the visual quality before the implantation or the adaptation of simultaneous vis ion tenses. They are based on the simulation of the vision that these tenses give to the implanted eye. Some experimental prototypes and commercial aberrometers or double pass systems have used to perform an optical quality characterization in vivo, but some issues have been reported. Taking into account all this information, the main goal of this thesis is the design and the assembly of a new open-field double-pass system with asymmetric focus that is suitable to characterize invivo optical quality in patients implanted or adapted with multifocal intraocular or contact lenses. In order to achieve this aim, different studies and processes were carried out Review of presbyopia corrections and the characterization of them (Clinical study about objective over-refraction wearing multifocal contact lenses); Verification of the suitability of one commerciat simulator (Clinical study with the commercial simulator VirtlOL (10lens S.l.)); Design and assembly of the double-pass system with asymmetric focus (Opto-mechanical design/ Validation of all the elements included in the system/ Optical validation of the system); Programming of the softwares to manage the system; Validation of the new prototype (Two clinical studies characterizing eyes implanted with multifocal introcular tenses by using the new system were done).
La visió és entesa i, universalment acceptada, com el sentit humà més valorat .Aquesta esta estructurada en tres parts principals: el sistema òptic (l'ull), el fot-sensor (la retina ocular) iel processador (el cervell). Si una d'aquestes parts es veu afectada per una disfunció o malaltia, la visió pot arribar a ser de molt baixa qualitat i, fins hi tot, inexistent Una de les disfuncions més comunes és la presbícia. La presbícia és una disfunció lligada a l'edat que pateix tota lla població a partir dels 40 anys, aproximadament. Consisteix en la pèrdua de la capacitat d'enfocar objectes propers (acomodació). Actualment, es troba un ampli nombre de possibles correccions. Per una banda, tenim les correccions temporals, com ulleres o lents de contacte progressives, i, per l'altre, correccions permanents, com lents intraoculars multifocals , ablacions corneals multifocals, lents intraoculars acomodatives, sistemes de monovisió, o modificacions esclerals, entre altres. Una altre disfunció associada a l'edat és la cataracta, la qual crea la opacificació del cristal·lí impedint una visió nítida. Conseqüentment, la cataracta és una de la deficiències visuals més estesa a partir dels 60 anys, afectant a la meitat de la població entre els 75 i els 85 anys . La única solució per eliminar les cataractes és eliminant les fibres opacificades i substituir-les per una lent intraocular quirúrgicament. Donat que tots els pacients amb cataractes són, a la vegada, prèsbites, està justificat que un nombre de pacients decideixi implantar-se lents intraoculars multifocals per substituir el seu cristal·lí. D'aquesta manera es solucionen dues degeneracions associades a l'edat en una sola cirurgia. Els joves prèsbites acostumen a optar per correccions prèsbites temporals, mentre que molts dels prèsbites amb cataractes opten per solucions permanents. Algunes de les correccions de la presbícia, com les lents de contacte o intraoculars multifocals , estan basades en el principi de visió simultània. Els dissenys òptics d'aquest tipus de lents són molt complexos, cosa que fa que la seva caracterització sigui molt complicada. Quan aquestes lents van aparèixer al mercat, només era possible caracteritzar-les òpticament abans de la seva implantació o adaptació de manera in vitro, i de caracteritzar-les visualment després de la seva adaptació o implantació de manera in vivo. Actualment, i gracies a tots els avenços tecnològics, diferents instruments clínics han estat desenvolupats per realitzar mesures de les qualitats visuals abans de la seva implantació. Tots ells, es basen en simular-li al pacient la visió que tindria després de ser implantat. Per un altre cantó, alguns prototips experimentals iaberrometres o sistemes de doble-pas comercials han estat utilitzats per dur a terme la caracterització de la qualitat in vim en pacients implantats o adaptats amb sistemes multifocals, pero diferents problemes han estat plantejats. Tenint en compte tota aquesta informació, el principal objectiu d'aquesta tesi ha estat la de dissenyar i muntar un nou sistema de doble-pas d'enfocament asimètric de camp obert que fos capaç de fer una caracterització de la qualitat òptica in vivo de pacients implantats o adaptats amb lents de contacte o intraoculars multifocals. I per arribar a aquest objectiu, s'han dut a terme els següents passos: Revisió de les correccions per a la presbícia i caracterització d'elles (Estudi clínic de la sobre-refracció objectiva de pacients adaptats amb lents de contacte multifocals); Validació de la capacitat de mesura d'un simulador comercial (Estudi clínic amb el simulador comercial VirtlOL (1OLens S.L); Disseny i muntatge del sistema de doble-pas amb enfocament asimètric (Disseny opto-mecànic/ Validació de tots els components del sistema/ Validació òptica del sistema); Programació dels programes informàtics que gestionen el sistema i processen

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Souza, Junior Joane Augusto de. « Avaliação da dureza Knoop da resina acrilica polimerizada por luz visivel, quando em contato com metal, e de sua rugosidade de superficie ». [s.n.], 2004. http://repositorio.unicamp.br/jspui/handle/REPOSIP/288643.

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Orientador: Renata C. M. Rodrigues Garcia
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba
Made available in DSpace on 2018-08-03T22:58:51Z (GMT). No. of bitstreams: 1 SouzaJunior_JoaneAugustode_D.pdf: 1017304 bytes, checksum: 9458ca58da06b1bc811cd227579cfbc2 (MD5) Previous issue date: 2004
Resumo: O objetivo deste estudo foi avaliar e comparar a rugosidade e dureza Knoop de uma resina acrílica fotopolimerizável com resinas termopolimerizáveis, quando em contato com metal. Foram confeccionadas 12 amostras medindo 30 mm de diâmetro e 4 mm de espessura, contendo em seu interior uma barra metálica de cobalto-cromo, exposta em uma das superfícies da amostra, para cada tipo de resina utilizada, sendo: grupo 1) resina acrílica polimerizada por energia de microondas (Onda-Cryl®); grupo 2) resina acrílica fotopolimerizável (Triad®); grupo 3) resina acrílica termopolimerizável convencional (Clássico®). As amostras foram acabadas e polidas com lixa d¿água de granulação 320, 400, 600 e 1000, e utilizada pasta de diamante de 1 µm. A rugosidade superficial (µm) da resina acrílica foi avaliada em equipamento Surfcorder SE 1700 calibrado com comprimento de onda limite de 0,8mm, percurso de medição de 3,2mm e velocidade de 0,5mm/s. A dureza Knoop (Kg/mm2) foi avaliada em equipamento Shimadzu HMV-2000 aplicando-se carga de 25 gramas por 10 segundos, nas distâncias de 50, 100, 200, 400 e 800 µm da barra metálica. Ambas as análises foram realizadas na mesma superfície polida da amostra, mas em lados opostos em relação ao metal. Os resultados de rugosidade foram submetidos a análise de variânica, teste de Tukey e teste t, e para dureza Knoop foram realizados a análise de variância, teste de Tukey e teste de Kruskal-Wallis. Foi observada diferença significativa (p < 0,05) tanto na dureza quanto na rugosidade da resina, sendo que a resina fotopolimerizável (grupo 2) apresentou os maiores valores (Ra = 0,11 e KHN 50 = 20,20; KHN 100 = 20,96; KHN 200 = 20,88; KHN 400 = 21,01 e KHN 800 = 21,44). Em relação às distâncias do metal não houve diferença significante (p > 0,05) para a dureza em 1 nenhum dos grupos estudados (grupo 1: KHN 50 =16,78; KHN 100 = 17,16; KHN 200 = 17,29; KHN 400 = 17,87; KHN 800 = 17,98; e grupo 3: KHN 50 = 17,07; KHN 100 = 17,06; KHN 200 = 17,21; KHN 400 = 17,78; KHN 800 = 17,96). Com estes resultados pode-se concluir que a resina acrílica fotopolimerizável apresenta maior rugosidade e dureza Knoop superficiais, em relação aos outros grupos, e o metal não interferiu na dureza do material
Abstract: The aim of this work was to evaluate and compare roughness and Knoop microhardness values of a visible light-cured resin to heat-cured resins, when in contact with metal. Therefore, twelve samples of 30 mm in diameter and 4 mm in thickness were made, containing a cobalt-chromium metal bar exposed in one of the surfaces, to each group of the according to the resin and polymerizing method: group 1) microwave oven-cured acrylic resin (Onda Cryl®); group 2) visible light-cured acrylic resin (Triad®); group 3) heat-cured in water acrylic resin (Clássico®). After processing, all samples were ground with 360, 400, 600 and 1000-grit abrasive papers in a polishing machine under refrigeration, followed by polishing cloths and 1-micron diamond suspension. Roughness of the acrylic resins were evaluated in micrometers (µm) with a surface texture measurer Surfcorder SE 1700 calibrated with a cut-off value of 0.8 mm and a tracing length of 3.2mm in 0.5mm/s. Knoop Microhardness (Kg/mm2) was assayed using a microhardness tester Shimadzu HMV-2000 set on 25 gram for 10 seconds, at 50, 100, 200, 400 and 800 µm from the metal bar. Roughness values were submitted to analysis of variance, Tukey¿s test and t-test and Knoop hardness values were submitted to analysis of variance, Tukey¿s test and Kruskal-Wallis¿ test. Statistically significant differences ( p < 0.05) were found for microhardness and roughness values, where group 2 presented the highest values (Ra = 0.11 and KHN 50 = 20.20; KHN 100 = 20.96; KHN 200 = 20.88; KHN 400 = 21.01 and KHN 800 = 21.44). Microhardness values in different distances from the metal bar were not significantly different (p < 0.05) (group 1: KHN 50 =16.78; KHN 100 = 17.16; KHN 200 = 17.29; KHN 400 = 17.87; KHN 800 = 17.98; and group 3: KHN 50 = 17.07; KHN 3 100 = 17.06; KHN 200 = 17.21; KHN 400 = 17.78; KHN 800 = 17.96). It was concluded that heat-cured in water acrylic resin showed the highest roughness and surface Knoop hardness values when compared to the other groups. Also, metal did not influence acrylic¿s hardness values
Doutorado
Protese Dental
Doutor em Clínica Odontológica

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Mussi, Claudia Motta. « Efeito da visita domiciliar intercalada com contato telefônico no conhecimento da doença, nas habilidades para o autocuidado e na adesão de pacientes com insuficiência cardíaca e internação recente : ensaio clínico randomizado ». reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/76157.

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Objetivo: Verificar o efeito de uma intervenção educativa de enfermagem combinada de visita domiciliar e contato telefônico em pacientes com internação recente por insuficiência cardíaca descompensada no conhecimento da doença, nas habilidades para o autocuidado e na adesão ao tratamento comparado ao acompanhamento convencional de pacientes no período de seis meses. Métodos: Ensaio Clínico Randomizado com pacientes que tiveram internação recente por insuficiência cardíaca descompensada. O grupo intervenção recebeu quatro visitas domiciliares e quatro contatos telefônicos para reforço das orientações em seis meses de acompanhamento; o grupo controle recebeu acompanhamento convencional sem visitas e sem contatos telefônicos. Resultados: Duzentos pacientes foram randomizados (101: intervenção e 99: controle). Após seis meses, observou-se melhora significativa no conhecimento e autocuidado para o grupo intervenção (P=0,001 e P<0,001), respectivamente; a adesão ao tratamento, aferida no final entre os grupos, foi significativamente maior no grupo intervenção (P<0,001). Conclusão: A estratégia de visita domiciliar para pacientes que internaram recentemente por insuficiência cardíaca descompensada foi efetiva na melhora dos desfechos avaliados e sua implementação merece ser considerada no Brasil visando evitar internações não planejadas.

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Mas, Aixalà Enric. « Caracterització dels paràmetres corneals per a l'adaptació de lents de contacte en casos de queratocon ». Doctoral thesis, Universitat Politècnica de Catalunya, 2019. http://hdl.handle.net/10803/667313.

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Introduction: The characterization of the corneal surface and the classification of keratoconus into diverse severity stages is a field of research in constant evolution, not only because of technology advances, but also with the definition of new parameters that allow a better understanding of the geometry, status and evolution of affected eyes, as compared with healthy eyes. Within the evolution of our knowledge about keratoconus, it is increasingly relevant to analyze the changes caused by this pathology to the morphology of the peripheral cornea with the purpose of successfully developing large diameter corneal contact lenses (CL) for these patients, to improve visual quality and comfort, with minimum interference with ocular physiology. Current Investigations: The objective of this series of studies was to improve our knowledge of corneal geometry as a whole and, in particular, to determine if corneal changes occurring in keratoconus are mainly corneal, limbal / scleral, or a combination of both. This information is key to design and fit large diameter corneal CL in patients with different stages of the condition, as a complementary or alternative solution to current fitting strategies. With this purpose in mind, Scheimpflug images at different corneal meridians were used to analyse several corneal and anterior segment parameters of eyes of patients with keratoconus at different stages of the condition. As such, one of the novel aspects of the present study consisted in a complete analysis of the anterior segment, not limited to parameters provided by the software of the Pentacam HR®, but also defining new parameters, not available in the current version of the software. These parameters, manually measured on Scheimpflug images, included a newly defined parameter (DL, or distance to the lens, distance from the end point of the corneal sagittal line to the anterior surface of the lens) which proved very useful for the required corneal-limbal characterization. The following step was to analyse the corneal periphery by measuring the corresponding peripheral corneal angles (at a chord length between 8.6 and 12.6 mm) and the degree of peripheral revolution symmetry (defined as the difference between the smallest and largest peripheral corneal angle for a particular eye). This was accomplished with a newly developed methodology, as the areas under study had not been previously explored with Scheimpflug images. Finally, a new design for a large diameter corneal CL was developed for keratoconus and a new mathematical model was implemented to calculate the parameters of these CLs from the previously obtained Scheimpflug images measurements. In order to conduct a practical validation of the viability of this new CL design and mathematical methodology in keratoconus, a preliminary clinical study on 20 eyes (10 patients) with different stages of the condition was conducted. Conclusions: Keratoconus was found to be associated with an increase in anterior chamber depth which, in turn, leads to increased values both in corneal internal sagittal length (as measured from the endothelium) and in the DL distance. Indeed, the increase in DL may be evidence of an anterior displacement of the corneal-limbal transition zone of the eye, with reference to the plane of the iris. Therefore, changes occurring in keratoconus would not only affect the cornea, but the whole of the anterior segment of the eye, including the limbal structures. A significant increase in corneal peripheral angle in the early stages of keratoconus that does not seem to progress in later stages of the condition was observed. The degree of peripheral revolution symmetry was not found to differ between healthy and keratoconus eyes. Therefore, CL with peripheral support and symmetry of revolution in this area may be fitted as successfully in keratoconus as in healthy eyes.
Introducció: Tant la caracterització de la superfície corneal com la classificació del queratocon en diferents estadis de gravetat es troben en contínua evolució, fruit no només de l’avenç tecnològic, sinó també de la definició de nous paràmetres amb els quals es fan aportacions que ajuden a comprendre millor la geometria, l’estat i l’evolució dels ulls afectats, en comparació amb els ulls sans. És en aquesta evolució del coneixement del queratocon que pren importància l’anàlisi de l’afectació que aquesta patologia produeix en la morfologia corneal perifèrica amb l’objectiu de fer una proposta satisfactòria de disseny de lents de contacte (LC) corneals de gran diàmetre per adaptar a pacients amb queratocon, amb l’objectiu de millorar la seva qualitat de visió amb la màxima comoditat possible i la mínima interferència en al fisiologia ocular. Estudis realitzats: L’objectiu d’aquesta sèrie d’estudis és aportar un millor coneixement de la geometria corneal en tota la seva extensió i, en particular, esbrinar si els canvis corneals produïts en el queratocon són predominantment corneals, limbals/esclerals o una combinació d’ambdós; una informació rellevant a l’hora d’adaptar LC corneals de gran diàmetre en pacients amb diferents estadis d’evolució de la patologia, com a complement o, fins i tot, alternativa a les opcions actuals d’adaptació. Així, s’han analitzat, a través de les imatges de Scheimpflug en diferents meridians oculars, una sèrie de paràmetres corneals i del segment anterior de l’ull a pacients afectats de queratocon en diferents estadis d’evolució. Un dels fets destacables d’aquest estudi suposa l’anàlisi, no només de paràmetres provinents del software propi del Pentacam HR®, sinó de paràmetres mesurats manualment sobre les imatges de Scheimpflug que el propi software no determina, incloent-hi la definició d’un nou paràmetre (distance to the lens, DL, o distància des del punt final de mesurament de la sagita al cristal·lí) que s’ha demostrat prou útil per a la caracterització corneolimbal desitjada. El següent pas ha estat analitzar la perifèria corneal a través del mesurament dels angles corneals perifèrics (corresponents a una longitud de corda d’entre 8,6 i 12,6 mm) i el grau de simetria de revolució perifèrica (diferència entre l’angle corneal perifèric més petit i més gran per a cada ull en particular) amb una metodologia creada sense altre referent anterior, donat que no es tenia constància que les zones estudiades en aquesta investigació haguessin estat mai investigades amb les imatges de Scheimpflug. Finalment, s’ha fet una proposta d’un nou disseny de LC corneal de gran diàmetre per a l’adaptació en casos de queratocon i s’ha desenvolupat un nou mètode de càlcul dels paràmetres d’aquestes lents a partir dels mesuraments fets prèviament sobre les imatges de Scheimpflug. Per tal de fer una comprovació pràctica que pogués aportar uns primers resultats en relació a la viabilitat de l’adaptació d’aquestes LC i del nou mètode de càlcul, s’han realitzat unes primeres experiències clíniques en 20 ulls afectats de queratocon (10 pacients) en diferents estadis d’evolució. Conclusions: El queratocon es troba associat a un increment de la profunditat de la cambra anterior que, al seu torn, implica valors més elevats, tant de la sagita interna (mesurada des de l’endoteli), com de la distància DL. L’increment de la DL seria indicatiu d’un desplaçament cap a la part anterior de l’ull de l’àrea de transició entre còrnia i esclera, amb referència al pla de l’iris. Per tant, els canvis produïts pel queratocon no només afecten la còrnia, sinó tot el segment anterior de l’ull, incloses les estructures límbiques. Existeix un increment significatiu de l’angle corneal perifèric en els estadis inicials del queratocon, el qual no sembla continuar a mesura que avança la patologia. L’angle perifèric mitjà en ulls amb queratocon és, de mitjana, 0,69° més gran que el dels ulls sans. El grau de simetria de revolució perifèrica no presenta diferències entre els grups d’ulls sans i ulls amb queratocon. Per tant, l’adaptació de LC que es recolzen sobre la perifèria corneal i tenen simetria de revolució en aquesta zona serà tan satisfactòria en ulls amb queratocon com ho és en ulls sans. Aquesta conclusió ha estat corroborada amb els resultats obtinguts en l’estudi clínic preliminar, amb uns bons resultats pel que fa a la millora de l’agudesa visual, a la satisfacció de l’usuari, en termes de qualitat visual i comoditat d’ús, i sense alteracions rellevants en la fisiologia ocular detectables en les visites de seguiment.

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Nakazawa, Takeshi. « THREE-DIMENSIONAL NON-CONTACT SURFACE PROFILERS FOR SEMICONDUCTOR IC PACKAGE INSPECTION ». Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/205472.

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The subject of this dissertation is the development of three-dimensional (3D) surface profilers for semiconductor back-end inspection. The value of this study is: 1) to provide a new phase-to-height relationship for Fourier Transform Profilometry (FTP) that is universal as it allows alternate FTP system architectures for a micrometer scale object measurement, and 2) to provide a new method for full field substrate warpage and ball grid array (BGA) coplanarity inspection using machine vision. The desire to increase electronic device performance has resulted in denser and smaller IC packaging. As the dimensions of the devices decrease, the requirements for substrate flatness and surface quality become critical in avoiding device failure. For a high yield production, there is an increasing demand in the requirement for the dimensional verification of height, which requires 3D inspection. Based on the current demands from the semiconductor industry, this dissertation addresses the development of fast in-line surface profilers for large volume IC package inspection. Specifically, this dissertation studies two noncontact surface profilers. The first profiler is based on FTP for measuring the IC package front surface, the silicon die and the epoxy underfill profile. The second profiler is based on stereovision and it is intended for inspecting the BGA coplanarity and the substrate warpage. A geometrical shape based matching algorithm is also developed for finding point correspondences between IC package images. The FTP profiler provides a 1 σRMS error of about 4 μm for an IC package sample in an area of 14 mm x 6.5 mm with a 0.13 second data acquisition time. For evaluating the performance of the stereovision system, the linearity between our system and a confocal microscope is studied by measuring a particular IC sample with an area of 38 mm x 28.5 mm. The correlation coefficient is 0.965 and the 2σdifference in the two methods is 26.9 μm for the warpage measurement. For BGA coplanarity inspection the correlation coefficient is 0.952 and the 2difference is 31.2 μm. Data acquisition takes about 0.2 seconds for full field measurements.

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Einestam, Ragnar, et Karl Casserfelt. « PiEye in the Wild : Exploring Eye Contact Detection for Small Inexpensive Hardware ». Thesis, Malmö högskola, Fakulteten för teknik och samhälle (TS), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20696.

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Ögonkontakt-sensorer skapar möjligheten att tolka användarens uppmärksamhet, vilketkan användas av system på en mängd olika vis. Dessa inkluderar att skapa nya möjligheterför människa-dator-interaktion och mäta mönster i uppmärksamhet hos individer.I den här uppsatsen gör vi ett försök till att konstruera en ögonkontakt-sensor med hjälpav en Raspberry Pi, med målet att göra den praktisk i verkliga scenarion. För att fastställaatt den är praktisk satte vi upp ett antal kriterier baserat på tidigare användning avögonkontakt-sensorer. För att möta dessa kriterier valde vi att använda en maskininlärningsmetodför att träna en klassificerare med bilder för att lära systemet att upptäcka omen användare har ögonkontakt eller ej. Vårt mål var att undersöka hur god prestanda vikunde uppnå gällande precision, hastighet och avstånd. Efter att ha testat kombinationerav fyra olika metoder för feature extraction kunde vi fastslå att den bästa övergripandeprecisionen uppnåddes genom att använda LDA-komprimering på pixeldatan från varjebild, medan PCA-komprimering var bäst när input-bilderna liknande de från träningen.När vi undersökte systemets hastighet fann vi att nedskalning av bilder hade en stor effektpå hastigheten, men detta sänkte också både precision och maximalt avstånd. Vi lyckadesminska den negativa effekten som en minskad skala hos en bild hade på precisionen, mendet maximala avståndet som sensorn fungerade på var fortfarande relativ till skalan och iförlängningen hastigheten.
Eye contact detection sensors have the possibility of inferring user attention, which can beutilized by a system in a multitude of different ways, including supporting human-computerinteraction and measuring human attention patterns. In this thesis we attempt to builda versatile eye contact sensor using a Raspberry Pi that is suited for real world practicalusage. In order to ensure practicality, we constructed a set of criteria for the system basedon previous implementations. To meet these criteria, we opted to use an appearance-basedmachine learning method where we train a classifier with training images in order to inferif users look at the camera or not. Our aim was to investigate how well we could detecteye contacts on the Raspberry Pi in terms of accuracy, speed and range. After extensivetesting on combinations of four different feature extraction methods, we found that LinearDiscriminant Analysis compression of pixel data provided the best overall accuracy, butPrincipal Component Analysis compression performed the best when tested on imagesfrom the same dataset as the training data. When investigating the speed of the system,we found that down-scaling input images had a huge effect on the speed, but also loweredthe accuracy and range. While we managed to mitigate the effects the scale had on theaccuracy, the range of the system is still relative to the scale of input images and byextension speed.

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Nixon, Alex D. « Visual Performance of Scleral and Soft Contact Lenses in Normal Eyes ». The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397498763.

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Waizenegger, Wolfgang. « Real-time 3D-based Virtual Eye Contact for Video Communication ». Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20159.

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Das Problem des fehlenden Augenkontaktes vermindert den Eindruck einer natürlichen Kommunikationssituation bei Videokonferenzen. Während eine Person auf den Bildschirm blickt, wird sie von Kameras aufgenommen, die sich normalerweise direkt daneben befinden. Mit dem Aufkommen von massiv paralleler Computer Hardware und ganz speziell den sehr leistungsstarken Spielegrafikkarten ist es möglich geworden, viele Eingabeansichten für eine Echtzeit 3D Rekonstruktion zu verarbeiten. Eine größere Anzahl von Eingabeansichten mildert Verdeckungsprobleme ab und führt zu vollständigeren 3D Daten. In dieser Arbeit werden neue Algorithmen vorgeschlagen, welche eine hochqualitative Echtzeit 3D Rekonstruktion, die kontinuierliche Anpassung der photometrischen Kameraparameter und die benutzerunabhängige Schätzung der Augenkontaktkameras ermöglichen. Die Echtzeit 3D Analyse besteht aus zwei komplementären Ansätzen. Einerseits gibt es einen Algorithmus, der auf der Verarbeitung geometrischer Formen basiert und auf der anderen Seite steht eine patchbasierte Technik, die 3D Hypothesen durch das Vergleichen von Bildtexturen evaluiert. Zur Vorbereitung für die Bildsynthese ist es notwendig, Texturen von verschiedenen Ansichten anzugleichen. Hierfür wird die Anwendung eines neuen Algorithmus zur kontinuierlichen photometrischen Justierung der Kameraparameter vorgeschlagen. Die photometrische Anpassung wird iterativ, im Wechsel mit einer 3D Registrierung der entsprechenden Ansichten, ausgeführt. So ist die Qualität der photometrischen Parameter direkt mit jener der Ergebnisse der 3D Analyse verbunden und vice versa. Eine weitere wichtige Voraussetzung für eine korrekte Synthese der Augenkontaktansicht ist die Schätzung einer passenden virtuellen Augenkontaktkamera. Hierfür wird die Augenkontaktkamera kontinuierlich an die Augenposition der Benutzer angeglichen. Auf diese Weise wird eine virtuelle Kommunikationsumgebung geschaffen, die eine natürlichere Kommunikation ermöglicht.
A major problem, that decreases the naturalness of conversations via video communication, is missing eye contact. While a person is looking on the display, she or he is recorded from cameras that are usually attached next to the display frame. With the advent of massively parallel computer hardware and in particular very powerful consumer graphics cards, it became possible to simultaneously process multiple input views for real-time 3D reconstruction. Here, a greater amount of input views mitigate occlusion problems and lead to a more complete set of 3D data that is available for view synthesis. In this thesis, novel algorithms are proposed that enable for high quality real-time 3D reconstruction, the on-line alignment of photometric camera parameters, and the automatic and user independent estimation of the eye contact cameras. The real-time 3D analysis consist of two complementary approaches. On the one hand, a shape based algorithm and on the other hand, a patch based technique that evaluates 3D hypotheses via comparison of image textures. Preparative to rendering, texture from multiple views needs to be aligned. For this purpose, a novel algorithm for photometric on-line adjustment of the camera parameters is proposed. The photometric adjustment is carried out iteratively in alternation with a 3D registration of the respective views. In this way, the quality of photometric parameters is directly linked to the 3D analysis results and vice versa. Based on the textured 3D data, the eye contact view is rendered. An important prerequisite for this task is the estimation of a suitable virtual eye contact camera. In this thesis, a novel approach is formulated that enables for an automatic adaptation to arbitrary new users. Therefor, the eye contact camera is dynamically adapted to the current eye positions of the users. In this way, a virtual communication environment is created that allows for a more natural conversation.

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Barreda, Alison M. « Determining Patient Preference for a Pharmacist-Administered Influenza Vaccination Program : Type of Visit and Contact Method for Annual Notification ». The University of Arizona, 2009. http://hdl.handle.net/10150/623906.

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Class of 2009 Abstract
OBJECTIVES: To determine patient preference for the type of visit for the receipt of the influenza vaccine from the pharmacist and to determine patient preference for contact method for annual notification of the influenza vaccine program. METHODS: This was a descriptive study using a short telephone survey. The first dependent variable was the preferred type of visit comparing appointment-based and predetermined walk-in clinics. The second dependent variable was the preferred method of contact for annual notification of a pharmacist administered influenza vaccination program (telephone, US post mail, email). RESULTS: The telephone survey was completed by 206 patients. Overall, study participants preferred appointment-based visits ( 81.2 %; p < 0.05) compared to a predetermined walk-in clinic (18.8%). Overall, study participants significantly preferred to be contacted for annual notification of a pharmacist administered influenza vaccination program via telephone (75.7%; p< 0.05) compared with US post mail and email. Based on the percentages observed, the second preferred method of contact was email (12.6%) and US post mail was the third preferred method of contact (11.7%). CONCLUSIONS: Patient preference for type of visit for pharmacist-administered influenza vaccine was appointment-based as opposed to predetermined walk-in clinic based. Patient preference for contact method for annual notification was telephone as opposed to email or postal mail.

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Grafton, Catherine E. « Binocular vision and three-dimensional motion perception : the use of changing disparity and inter-ocular velocity differences ». Thesis, University of St Andrews, 2011. http://hdl.handle.net/10023/1922.

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This thesis investigates the use of binocular information for motion-in-depth (MID) perception. There are at least two different types of binocular information available to the visual system from which to derive a perception of MID: changing disparity (CD) and inter-ocular velocity differences (IOVD). In the following experiments, we manipulate the availability of CD and IOVD information in order to assess the relative influence of each on MID judgements. In the first experiment, we assessed the relative effectiveness of CD and IOVD information for MID detection, and whether the two types of binocular information are processed by separate mechanisms with differing characteristics. Our results suggest that, both CD and IOVD information can be utilised for MID detection, yet, the relative dependence on either of these types of MID information varies between observers. We then went on to explore the contribution of CD and IOVD information to time-to-contact (TTC) perception, whereby an observer judges the time at which an approaching stimulus will contact them. We confirmed that the addition of congruent binocular information to looming stimuli can influence TTC judgements, but that there is no influence from binocular information indicating no motion. Further to this, we found that observers could utilise both CD and IOVD for TTC judgements, although once again, individual receptiveness to CD and/or IOVD information varied. Thus, we demonstrate that the human visual system is able to process both CD and IOVD information, but the influence of either (or both) of these cues on an individual’s perception has been shown to be mutually independent.

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Ramalingam, Nagarajan. « Non-contact multispectral and thermal sensing techniques for detecting leaf surface wetness ». Connect to this title online, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1104392582.

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Thesis (Ph. D.)--Ohio State University, 2005.
Title from first page of PDF file. Document formatted into pages; contains xxii, 271 p.; also includes graphics (some col.) Includes bibliographical references (p. 206-214).

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Li, Qiang. « Effects of Adaptive Discretization on Numerical Computation using Meshless Method with Live-object Handling Applications ». Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/14480.

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The finite element method (FEM) has difficulty solving certain problems where adaptive mesh is needed. Motivated by two engineering problems in live-object handling project, this research focus on a new computational method called the meshless method (MLM). This method is built upon the same theoretical framework as FEM but needs no mesh. Consequently, the computation becomes more stable and the adaptive computational scheme becomes easier to develop. In this research, we investigate practical issues related to the MLM and develop an adaptive algorithm to automatically insert additional nodes and improve computational accuracy. The study has been in the context of the two engineering problems: magnetic field computation and large deformation contact. First, we investigate the effect of two discretization methods (strong-form and weak-form) in MLM for solving linear magnetic field problems. Special techniques for handling the discontinuity boundary condition at material interfaces are proposed in both discretization methods to improve the computational accuracy. Next, we develop an adaptive computational scheme in MLM that is comprised of an error estimation algorithm, a nodal insertion scheme and a numerical integration scheme. As a more general approach, this method can automatically locate the large error region around the material interface and insert nodes accordingly to reduce the error. We further extend the adaptive method to solve nonlinear large deformation contact problems. With the ability to adaptively insert nodes during the computation, the developed method is capable of using fewer nodes for initial computation and thus, effectively improves the computational efficiency. Engineering applications of the developed methods have been demonstrated by two practical engineering problems. In the first problem, the MLM has been utilized to simulate the dynamic response of a non-contact mechanical-magnetic actuator for optimizing the design of the actuator. In the second problem, the contact between the flexible finger and the live poultry product has been analyzed by using MLM. These applications show the developed method can be applied to a broad spectrum of engineering applications where an adaptive mesh is needed.

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Jones, Helen Mary Fletcher. « Crossing international boundaries : the relevance and effect of international visits, placements and contacts in the training and education of youth and community workers ». Thesis, University of Leeds, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.444752.

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Ben-Naser, Abdusalam. « Measurement of range of motion of human finger joints, using a computer vision system ». Thesis, Loughborough University, 2011. https://dspace.lboro.ac.uk/2134/12531.

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Assessment of finger range of motion (ROM) is often required for monitoring the effectiveness of rehabilitative treatments and for evaluating patients' functional impairment. There are several devices which are used to measure this motion, such as wire tracing, tracing onto paper and mechanical and electronic goniometry. These devices are quite cheap, excluding electronic goniometry; however the drawbacks of these devices are their lack of accuracy and the time- consuming nature of the measurement process. The work described in this thesis considers the design, implementation and validation of a new medical measurement system utilized in the evaluation of the range of motion of the human finger joints instead of the current measurement tools. The proposed system is a non-contact measurement device based on computer vision technology and has many advantages over the existing measurement devices. In terms of accuracy, better results are achieved by this system, it can be operated by semi-skilled person, and is time saving for the evaluator. The computer vision system in this study consists of CCD cameras to capture the images, a frame-grabber to change the analogue signal from the cameras to digital signals which can be manipulated by a computer, Ultra Violet light (UV) to illuminate the measurement space, software to process the images and perform the required computation, a darkened enclosure to accommodate the cameras and UV light and to shield the working area from any undesirable ambient light. Two calibration techniques were used to calibrate the cameras, Direct Linear Transformation and Tsai. A calibration piece that suits this application was designed and manufactured. A steel hand model was used to measure the fingers joint angles. The average error from measuring the finger angles using this system was around 1 degree compared with 5 degrees for the existing used techniques.

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Durand-Texte, Thomas. « Mesure de vibrations par vision 3D ». Thesis, Le Mans, 2019. http://www.theses.fr/2019LEMA1003/document.

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La finalité de cette thèse est d’étudier la pertinence et les limites des méthodes de vision 3D couplées à une caméra ultra-rapide pour la mesure de champs vibratoires, sans contact et de manière synchrone, dans le domaine des fréquences associées à la vibro-acoustique. Un premier montage pseudo stéréoscopique, issu de la robotique, mobilisant un jeu de quatre miroirs afin de générer deux vues virtuelles à partir d’une seule caméra réelle, a été testé sur une plaque et un haut-parleur. Les résultats, validés par comparaison avec ceux obtenus avec un vibromètre laser, attestent de la pertinence de l’approche en dépit des contraintes liées aux éléments optiques. Dans une logique de simplification, trois autres montages ont alors été proposés et testés, permettant de concevoir deux techniques de mesure de vibration plein champ et une méthode itérative de rectification d’images (IRIs), adaptées au contexte. La méthode sans miroir utilise une ligne mathématique pour la triangulation et est fondamentalement adaptée à la mesure de vibrations mono-axiales d'objets globalement plans, affichant des déplacements non-répétables selon la normale de la surface ou selon un axe connu. La méthode à caméras asynchrones, quant à elle, utilise une caméra ultra-rapide et une caméra rapide, et permet la mesure de vibrations multi-axiales de phénomènes vibratoires 3D. Les résultats obtenus sur le capot d’une voiture et sur un haut-parleur attestent de son potentiel pour la caractérisation de panneaux ou le test qualité de fin de chaine d’assemblage de haut-parleurs par exemple. En conclusion, les trois protocoles de mesure et les résultats associés sont comparés afin de cibler leurs potentialités et limites respectives dans le contexte de la mesure de vibrations
The objective of this Ph.D is to study the relevance and limits of 3D vision methods coupled to high-speed cameras and applied to non-contact synchronous vibration measurement, in the vibro-acoustic range of frequencies. A first pseudo stereoscopic set-up, taken from robotics, using a four-mirror adapter in order to generate two virtual viewpoints from a single real camera, has been tested on a plate and a loudspeaker. The results, validated by comparison with those obtained with a laser vibrometre, prove the relevance of the approach, despite some constraints related to the optical elements. In a logic of simplification, three other set-ups have then been proposed and tested, allowing designing two full-field vibration measurement techniques and a method for the Iterative Rectification of Images (IRIs), adapted to the context. The no-mirror method uses a mathematical line to triangulate positions and is basically suited to measure the single-axis vibrations of globally plane objects, displaying non-repeatable displacements along the normal of the surface or along a known axis. The asynchronous cameras technique requires a high-speed and an industrial camera used simultaneously to measure the multi-axis displacements of 3D vibratory phenomena. The results obtained on a car bonnet and a loudspeaker prove its potential to characterise large panels or to carry out end-of-line testing of loud-speakers for example. In conclusion, the three measurement protocols and the associated results are compared in order to assess their respective potentialities and limits in the context of vibration measurement

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Sano, Ronaldo Yuiti. « Avaliação oftalmológica e psicofísica do sistema visual de portadores de albinismo ». Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/47/47135/tde-12122017-090536/.

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O albinismo e uma alteracao genetica rara que compromete a producao de melanina. As alteracoes clinicas consistem na falta de pigmentacao da pele, cabelo e pelos. Apresenta alteracoes oftalmologicas importantes, que comprometem a acuidade visual de forma severa, na grande maioria dos casos. As alteracoes oftalmologicas sao, ametropias, nistagmo, rarefacao do epitelio pigmentado da iris e da retina, hipoplasia foveal e decussacao anomala do nervo optico. Este estudo foi dividido em tres diferentes partes com os seguintes objetivos principais: Parte 1: Analise comparativa entre o grau de transparencia da iris (GTI), o grau de transparencia da retina (GTR) e a espessura da regiao macular com a acuidade visual nos pacientes com albinismo. Parte 2: Teste de sensibilidade ao contraste espacial de luminancia e ofuscamento com lentes de contato filtrantes em ambientes claros e escuros. Parte 3: Avaliacao da visao de cores, utilizando\\se o teste de Pranchas de Ishihara e o Cambridge Color Test (CCT). Material\' e\' Métodos: Participaram do estudo 121 individuos albinos, com idade media de 31,18 (} 15,47) anos, o que totalizou 242 olhos. Os participantes foram divididos em diferentes grupos nas tres partes do estudo, alguns participaram de uma ou mais partes. Na primeira parte os participantes foram submetidos a consulta oftalmologica, classificacao do grau de transparencia da iris e da retina em uma nova classificacao baseada em quatro diferentes graus de transparencia, alem de avaliacao foveal pelo exame de Tomografia de Coerencia Optica (OCT). Na segunda parte, os participantes foram submetidos ao teste de contraste computadorizado, utilizando lentes de contato filtrante e transparentes, em ambientes claros e escuros. Nesta etapa foi avaliada a influencia da lente filtrante na sensibilidade de contraste visual dos individuos com albinismo. Na terceira parte, os participantes foram submetidos aos testes de Pranchas de Ishihara e de Cambridge Colour Test (CCT), para avaliacao da visao de cores nos pacientes albinos. Resultados: Os resultados foram os seguintes: Parte\'1: A correlacao entre AV logMAR e GTI foi positiva (+0,569) e significativa (p<0,001). A correlacao entre AV logMAR e GTR foi positiva (+0,531) e significativa (p<0,001). A correlacao entre AV logMAR e a espessura macular nao foi significativa (p=0,105). A correlacao entre GTI e GTR foi positiva (+ 0,627) e significativa (p<0,001). A correlacao entre espessura macular e GTI nao foi significativa (p=0,397). A correlacao entre espessura macular e GTR nao foi significativa (p=0,458). Parte 2: Houve melhora estatisticamente significante da sensibilidade ao contraste com as lentes filtrantes em relacao as lentes transparentes no ambiente de ofuscamento (claro), na frequencia de 0,3 cpg, 0,6 cpg e 1,0 cpg (ciclos por grau). Nao houve melhora significante nas frequencia 2,0 cpg e 4,0 cpg. Nao houve melhora estatisticamente significante da sensibilidade ao contraste de lentes filtrantes em relacao as lentes transparentes no ambiente escuro (penumbra) em nenhuma das frequencias espaciais estudadas. Parte\' 3: Todos os individuos com albinismo nao apresentaram nenhuma alteracao de visao de cores no teste de Pranchas de Ishihara. O CCT demonstrou piora no limiar de deteccao de cores significativa nos eixos protan (p=0,021) e deutan (p=0,017), mas nao houve diferenca no eixo tritan (p=0,212). Os testes estatisticos sugerem que uma amostra maior seja estudada para validacao dos resultados
Albinism is a rare genetic alteration that compromises the production of melanine in all body tissues. The clinical alterations are the lack of pigment in the skin and hair. It presents important ophthalmological changes that compromise the visual acuity, in most cases. The ophthalmological changes are: ametropia, nystagmus, iris pigmented epithelium rarefaction, retina pigmented epithelium rarefaction, foveal hipoplasia and abnormal optic nerve decussation. This study has been divided in three different parts and had the following main objectives: Part 1, comparative analysis of the iris transparency degree (ITD), the retina transparency degree (RTD) and macular thickness with the visual acuity in albino patients. Part 2: Spatial contrast sensitivity test of luminance and outshine wearing contact lenses with filters in light and dark environments. Part 3: color vision evaluation using the Ishihara Test and the Cambridge Color Test (CCT). For the study 121 individuals with albinism were included with an average of 31,18 years old } 15,47, a total of 242 eyes. The participants were divided in different groups in the three parts of the study, some participated in one or more parts. In the first part the participants have been through an ophthalmological exam, classification of the iris transparency degree (ITD) and the retinal transparency degree (RTD) by a new classification based in 4 different degrees of transparency. Foveal evaluation by the Optic Coherence Tomography exam (OCT) was made in the first part of this study. In the second part, the participants have been submitted to the computerized contrast test, using filtered and transparent contact lenses in light and dark environments. In this part the influence of the filtering lenses in the visual contrast sensitivity in the albinism patients has been evaluated. In the third part, the participants have been submitted to Ishihara Test and Cambridge Color Test in order to evaluate the color vision in albino patients. The results are as follows: Part\' 1: the correlation between visual acuity in Logarithm of the Minimum Angle of Resolution (logMAR) and ITD was positive (+0,569) and significant (p<0,001). The correlation between visual acuity in logMAR and RTD was positive (+0,531) and significant (p<0,001). The correlation between visual acuity in logMAR and the macular thickness was not significant (p=0,105). The correlation between ITD and RTD was positive (+ 0,627) and significant (p<0,001). The correlation between the macular thickness and the ITD was not significant (p=0,397). The correlation between the macular thickness and the RTD was not significant (p=0,458). Part\'2: There has been a statistically significant improvement of the contrast sensitivity wearing the filtering lenses in relation to the transparent ones in bright environment, in the frequencies of 0,3 cycles per degree (cpd), 0,6 cpd and 1,0 cpd. There has been no significant improvement in the frequencies 2,0 cpd and 4,0 cpd. There has been no statistically significant improvement in contrast sensitivity wearing the filtering lenses in relation to the transparent one in the dark environment (shadow) in any of the spatial frequencies studied. Part\' 3: all albinism patients did not present any color vision change in the Ishihara Test. The CCT has shown a worsening in the color detection threshold in the protan axis (p=0,021) and deutan axis (p=0,017), but there has been no difference in the tritan axis (p=0,212). The statistic tests show that a bigger sample is recommended to confirm part 3 results

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Toseeb, Mohammed U. « Effect of the Muslim Headscarf on Face Perception. A series of psychological experiments looking at how the Muslim headscarf influences the perception of (South Asian) faces ». Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/5522.

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The Muslim headscarf conceals the hair and other external features of a face. For this reason it may have implications for the recognition of such faces. The experiments reported in this thesis aimed to investigate anecdotal reports, which suggested that headscarf wearing females are more difficult to recognise. This was done by employing a series of experiments which involved a yes/no recognition task. The stimuli that were used were images of South Asian females who were photographed wearing a Muslim headscarf (HS), with their own hair visible (H), and a third set of stimuli were produced in which their external features were cropped (CR). Most importantly, participants either took part in the condition in which the state of the external features remained the same between the learning and test stage (Same) or the condition in which they were switched between the two stages (Switch). In one experiment participants completed a Social Contact Questionnaire. Surprisingly, in the Same condition, there was no difference in the recognition rates of faces that were presented with hair, with headscarf, or cropped faces. However, participants in the Switch condition performed significantly worse than those in the Same condition. It was also found that there was no difference in the % of fixations to the external features between the Same and Switch condition, which implied that the drop in performance between the two conditions was not mediated by eye-movements. These results suggest that the internal and external features of a face are processed interactively and, although the external features were not fixated on, a manipulation to them caused a drop in performance. This was confirmed in a separate experiment in which participants were unable to ignore the external features when they were asked to judge the similarity of the internal features of pairs of faces. Pairs of headscarf faces were rated as being more similar compared to pairs of faces with hair. Finally, for one group of participants it was found that contact with headscarf-wearing females was positively correlated with the recognition of headscarf-wearing faces. It was concluded that the headscarf per se did not impair face recognition and that there is enough information in the internal features of a face for optimal recognition, however, performance was disrupted when the presence or absence of the headscarf was manipulated.

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Toseeb, Mohammed Umar. « Effect of the Muslim headscarf on face perception : a series of psychological experiments looking at how the Muslim headscarf influences the perception of (South Asian) faces ». Thesis, University of Bradford, 2012. http://hdl.handle.net/10454/5522.

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The Muslim headscarf conceals the hair and other external features of a face. For this reason it may have implications for the recognition of such faces. The experiments reported in this thesis aimed to investigate anecdotal reports, which suggested that headscarf wearing females are more difficult to recognise. This was done by employing a series of experiments which involved a yes/no recognition task. The stimuli that were used were images of South Asian females who were photographed wearing a Muslim headscarf (HS), with their own hair visible (H), and a third set of stimuli were produced in which their external features were cropped (CR). Most importantly, participants either took part in the condition in which the state of the external features remained the same between the learning and test stage (Same) or the condition in which they were switched between the two stages (Switch). In one experiment participants completed a Social Contact Questionnaire. Surprisingly, in the Same condition, there was no difference in the recognition rates of faces that were presented with hair, with headscarf, or cropped faces. However, participants in the Switch condition performed significantly worse than those in the Same condition. It was also found that there was no difference in the % of fixations to the external features between the Same and Switch condition, which implied that the drop in performance between the two conditions was not mediated by eye-movements. These results suggest that the internal and external features of a face are processed interactively and, although the external features were not fixated on, a manipulation to them caused a drop in performance. This was confirmed in a separate experiment in which participants were unable to ignore the external features when they were asked to judge the similarity of the internal features of pairs of faces. Pairs of headscarf faces were rated as being more similar compared to pairs of faces with hair. Finally, for one group of participants it was found that contact with headscarf-wearing females was positively correlated with the recognition of headscarf-wearing faces. It was concluded that the headscarf per se did not impair face recognition and that there is enough information in the internal features of a face for optimal recognition, however, performance was disrupted when the presence or absence of the headscarf was manipulated.

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Shirazi, Nejad Yegane, et Jessica Nilsson. « Kontaktfamiljsinsatsen : Unga vuxnas upplevelser av insatsen kontaktfamilj som barn ». Thesis, Stockholms universitet, Institutionen för socialt arbete - Socialhögskolan, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-77596.

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The purpose of this study was to describe and analyse a group of young adults’ childhood experiences of the intervention "contact family". The used methods were qualitative interviews and a standardised formulary with life questions, to strengthen the interviews and to compare data. The theoretical frame was taken from Bronfenbrenner’s child development theory and Antonovsky’s salutogenic perspective, which we supplemented with Hilchen Sommerschild’s theory about the "conditions of control". The results showed that all of the interviewed clients were positive to the intervention. They got to do things with their contact families that they did not do at home – the opportunity to an environmental change, the feeling of appreciation and a better every-day life with new perspectives. Some felt that it was negative that their contact families lived on the country side, that the contact family itself had problems of their own, and that it was hard to adapt to the new roles of the family. The conclusion was that the intervention of the contact families mainly was positive and seemed to be significant for the clients.

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Tauste, Francés Ana. « Valoración de las alteraciones oculares y visuales asociadas al uso de lentes de contacto en trabajadores expuestos a pantallas de visualización de datos ». Doctoral thesis, Universidad de Alicante, 2016. http://hdl.handle.net/10045/70349.

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Antecedentes: El elevado número de personas que trabajando con ordenador utiliza lentes de contacto plantea la cuestión sobre si la suma de estos dos factores de riesgo para la salud visual puede originar un agravamiento de las alteraciones oculares y visuales. Objetivos: Los tres objetivos principales de esta tesis fueron: 1) sintetizar el conocimiento científico sobre las alteraciones oculares y visuales relacionadas con la exposición a ordenador en usuarios de lentes de contacto entre el año 2003 y el 2013; 2) analizar la relación entre la presencia de Síndrome Visual Informático (SVI) en trabajadores expuestos a ordenador y el uso de lentes de contacto, según las características del material de las lentes de contacto, así como observar qué sucede a medida que aumentan las horas de uso de ordenador en el trabajo; y por último 3) analizar el efecto que producen lentes de contacto de diferentes materiales sobre la superficie ocular y el estado de la película lagrimal en trabajadores expuestos a ordenador durante su jornada laboral. Metodología: Para el primer objetivo se realizó una revisión de artículos científicos (2003-2013) en español o inglés, utilizando la metodología de Scoping Review, en Medline a través de PubMed y en Scopus. La pertinencia de las referencias se decidió analizando el título y el resumen, y teniendo en cuenta los criterios de exclusión, que obedecían a no incluir artículos que no se adaptaran a la temática por centrarse solo en efectos del uso de lentes de contacto o de pantallas, o por tratar de alteraciones oculares diversas. Para el segundo y tercer objetivo se llevó a cabo un estudio observacional de diseño transversal en trabajadores de la administración pública de la provincia de Alicante (España). El estudio se realizó de noviembre de 2013 a febrero de 2014, en colaboración con el Instituto Valenciano de Seguridad y Salud en el Trabajo (INVASSAT), que se encarga de la vigilancia de la salud de estos trabajadores. Durante estas fechas un total de 496 trabajadores acudieron a su revisión. Para la realización de este estudio, a las pruebas habituales de la revisión rutinaria de vigilancia de la salud de estos trabajadores, se incluyeron pruebas específicas para conocer el estado de la superficie ocular y de la película lagrimal (hiperemia bulbar, limbar y tarsal, hipertrofia tarsal, tinción corneal, tiempo de rotura lagrimal y Schirmer), un cuestionario sobre sintomatología ocular y visual cuando se utiliza el ordenador en el trabajo (Cuestionario de Síndrome Visual Informático), así como una serie de preguntas sobre el uso de éste y en relación a las lentes de contacto. De los 496 trabajadores, el 100% accedió a contestar el cuestionario y las preguntas acerca del uso de ordenador y las lentes de contacto, y el 61,7% (n = 306 trabajadores) a realizarse además las pruebas de la superficie ocular y lágrima. En cuanto al análisis estadístico, para el objetivo 2 se llevó a cabo una regresión logística para calcular la asociación cruda (ORc) y ajustada por sexo y edad (ORa) entre SVI y los factores individuales y laborales, y entre SVI y el tipo de lentes de contacto. Para el objetivo 3 se utilizó un modelo lineal generalizado con el que calcular el riesgo relativo crudo (RRc) y ajustado por edad y sexo (RRa) para medir la asociación entre alteraciones de la superficie ocular y de la lágrima y el uso de lentes de contacto y el tipo de lente. Resultados: En relación al primer objetivo la búsqueda inicial aportó 114 referencias, tras aplicar criterios de inclusión/exclusión se incluyeron seis artículos. Todos ellos ponen de manifiesto que las alteraciones al utilizar el ordenador son más prevalentes en los usuarios de lentes de contacto, con prevalencias que oscilan de 16,9 a 95,0% en los usuarios y de 9,9 a 57,5% en no usuarios, y con una probabilidad cuatro veces mayor de padecer ojo seco (OR: 4,07; IC 95% 3,52-4,71). Las lentes de hidrogel de silicona son las que se asocian a mayor confort. El resultado principal del estudio que responde al segundo objetivo es que los trabajadores que utilizan lentes de contacto y están expuestos al ordenador más de 6 horas/día tienen más probabilidades de padecer SVI que los no usuarios de lentes de contacto trabajando con el ordenador la misma cantidad de tiempo (ORa: 4,85; IC 95% 1,25 – 18,80). El tipo de lente parece ser un factor determinante en la presencia del síndrome. Aunque no alcanza significación estadística, la tendencia observada sugiere que llevar lentes de contacto de hidrogel convencional, e incluso más en el caso de las lentes de hidrogel de silicona, aumenta la probabilidad de padecer SVI, y que esta probabilidad se incrementa a más horas de uso de ordenador. Por último, los resultados del tercer objetivo muestran que los trabajadores expuestos a ordenador que llevan lentes de contacto tienen más probabilidades de padecer hiperemia bulbar (RRa: 1,69; IC 95% 1,25-2,30), hiperemia limbar (RRa: 2,87; IC 95% 1,88-4,37), hiperemia tarsal (RRa: 2,53; IC 95% 1,35-4,73), e hipertrofia tarsal (RRa: 7,03; IC 95% 1,31-37,82) que los no usuarios. De estas alteraciones, los indicadores para hiperemia limbar y tarsal son incluso mayores en aquellos expuestos al ordenador más de 4 horas/día. Las lentes de hidrogel convencional e hidrogel de silicona se relacionan con mayores alteraciones de la superficie ocular, especialmente las primeras. Sin embargo, las alteraciones de la película lagrimal no parecen estar relacionadas con el uso de lentes de contacto, aunque la prevalencia de resultados alterados de Schirmer y del tiempo de rotura lagrimal es muy elevada en todos los trabajadores incluidos en el estudio (47,6% y 76,3% respectivamente). Conclusiones: La revisión de la literatura pone de manifiesto que los usuarios de ordenador padecen más alteraciones oculares y visuales cuando además son usuarios de lentes de contacto, pero los estudios son escasos y con resultados no concluyentes, en el sentido de que las observaciones entre los diferentes estudios son inconsistentes. El uso habitual de lentes de contacto cuando se está expuesto a ordenador 6 horas o más en el trabajo incrementa el SVI. En estas condiciones, hay una tendencia a mayores problemas en los usuarios de lentes de hidrogel convencional y lentes de hidrogel de silicona, especialmente en los usuarios de éstas últimas. Del mismo modo, el uso regular de lentes de contacto durante la exposición a ordenador incrementa el riesgo de hiperemia bulbar, limbar, tarsal, e hipertrofia tarsal. En el caso de la hiperemia limbar y tarsal, el riesgo es mayor entre aquellos que utilizan el ordenador más de 4 horas al día. Respecto al material, los usuarios de lentes de hidrogel convencional tienen el mayor riesgo de desarrollar alteraciones de la superficie ocular, seguidos por los usuarios de lentes de hidrogel de silicona. La elevada prevalencia de resultados alterados en tiempo de rotura lagrimal y Schirmer, independientemente del uso de lentes de contacto, sugiere que el uso de ordenador tiene un alto impacto en las características de la película lagrimal.

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Santos, Rubens Batista. « Relação entre responsabilidade social corporativa e identidade de marca : a visão dos gestores de nível médio numa empresa de contact center em Uberlândia-MG ». Universidade Federal de Uberlândia, 2005. https://repositorio.ufu.br/handle/123456789/12037.

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Mestre em Administração
Esta dissertação de mestrado procurou compreender o conceito de Responsabilidade Social Corporativa, denominada neste estudo por CSR - Corporate Social Responsibility - com o objetivo de esclarecer as dimensões que esta categoria organizacional assume nos dias atuais, a partir de uma abordagem ética fundamentada na teoria da Business Ethics. Também foi estudado o conceito mercadológico de Sistema de Identidade de Marca, com o objetivo de investigar as dimensões desta categoria que se relacionam com a responsabilidade social corporativa. A partir do referencial teórico foi realizado um estudo de caso com o objetivo de levantar, descrever e analisar como o corpo gerencial de nível médio da ACS (Algar Call Center Service S/A) estabelece a relação entre a gestão da Responsabilidade SocialCorporativa na perspectiva da business ethics e a gestão do Sistema de Identidade de Marca. As evidências foram coletadas por meio de observações, análises de documentos e entrevistas semi-estruturadas, sendo utilizada a abordagem qualitativa. A análise dos dados utilizou como técnica analítica a descrição geral do caso seguida da análise das proposições teóricas, verificando-se a relação das dimensões das categorias de análise com as práticas gerenciais relatadas e observadas no contexto empresarial. Como resultado da pesquisa parece possível afirmar que o alinhamento do sistema de gestão da CSR e da identidade de marca possa auxiliar na tomada de decisão mercadológica por uma proposta de valor que integre benefícios de valor econômico e de valor social à marca. Esta integração dos dois sistemas de gestão estabelece associações genuínas e ricas em significado estético e ético com a marca. Uma identidade de marca fundamentada em valores sociais poderá fortalecer o relacionamento com os stakeholders e promover o respeito à diversidade cultural, características emergentes da gestão empresarial no século XXI.

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Déprez, Alexandra. « L'effet de la visite parentale chez le bébé placé en pouponnière : une étude exploratoire des réactions du bébé avant, pendant et après un contact avec ses parents ». Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015PA05H111.

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Notre étude explore des réactions du bébé vivant en pouponnière à la visite parentale. Cette étude s'inscrit dans la continuité des études sur les effets de la carence de soins et de la séparation. Objectifs : savoir comment le bébé réagit à la visite de ses parents, si tous les bébés ont le même bénéfice à recevoir la visite de leurs parents, et quels sont les facteurs impliqués dans la réaction du bébé. Méthode : étude de la réaction d'un groupe de 15 bébés vivant en pouponnière (2-36 mois) à la visite de leurs parents sur 24 heures par un protocole de test-re-test du comportement de retrait relationnel (ADBB 5 fois), de la concentration de cortisol salivaire (8 fois),d'un indice de comportement difficile le jour et la nuit avant et après la visite. Ces variables ont été étudiées en lien avec les caractéristiques de l'enfant(âge, développement, genre, rang dans la fratrie), de l'interaction parents-enfants(sensibilité, synchronie dyadique), les caractéristiques de la visite (fréquence, durée), du placement (durée, raison, âge au moment du placement), ainsi que les caractéristiques parentales(âge, dépression, anxiété, sensibilité à l'évaluation, santé mentale, soutien social, traumatismes, représentations d'attachement). Résultats : Trois types de profils de bébés ont pu être mis en évidence en fonction de leurs réactions à la visite parentale : - celui des bébés qui réagissent bien au contact de leurs parents et qui souffrent à la séparation au retour de la visite. Ces bébés ont un meilleur développement, leurs parents sont plus sensibles que ceux des autres groupes et ils bénéficient des visites. Leur niveau de cortisol baisse à la visite et remonte à la séparation. -des bébés qui réagissent par davantage de retrait relationnel au contact de leurs parents : Ces bébés ne montrent pas de détresse à la séparation. Ils apparaissent mieux adaptés à la vie dans l'institution (moins de retrait relationnel). Leurs parents sont beaucoup moins sensibles que ceux des autres. Leur niveau de cortisol est élevé globalement et pendant la visite. Ces bébés sont placés plus tôt que les deux autres groupes. -les bébés qui ne montrent aucune réaction au contact avec leurs parents en termes de retrait relationnel. Ils ont des niveaux de cortisol salivaire les plus bas. Ils ne se distinguent pas particulièrement des autres pour ce qui concerne les autres caractéristiques évaluées hors la durée de visite. Ce groupe apparaît à risque psychopathologique puisqu' il montre un niveau constant et élevé de retrait relationnel associé à des niveaux plus bas de cortisol salivaire et la moindre réactivité de l'axe HPA. La recherche a aussi permis de mettre en évidence l'effet de différentes variables sur les réactions du bébé à la visite parentale. Les plus importantes semblent être la qualité des interactions parents-enfants, le développement des enfants, les caractéristiques du placement et de la visite. Différents effets ont pu être mis en évidence : -un effet de deuil au retour de la visite pour les enfants qui ont eu un bon contact avec leurs parents. -un effet d'anticipation du stress de la visite pour les bébés qui réagissent mal au contact de leurs parents. -un effet de soulagement au retour de la visite pour les bébés qui réagissent mal au contact de leurs parents. -un effet de contamination pour certains enfants le lendemain de la visite, tous appartenant au groupe des enfants qui réagissent mal au contact de leurs parents. -un effet positif de la visite pour les enfants qui réagissent bien en contact de leurs parents. L'ensemble des résultats est discuté par rapport à la littérature, aux implications de théorique et juridique de l'étude du maintien du contact pour les bébés séparés de leurs parents, ainsi que les applications en termes de recherche et de clinique
Our research is an exploratory study of the reactions of the baby living in residential nursery to parental contact. This study is in continuaty with studies on the effects of early infant neglect and separation. Objectives: explore how babies react to parental contact if all babies have the same benefit to receive visits from their parents, and what are the factors involved in the baby's reaction to parental contact. Method: study of the reaction of a group of 15 infants/babies living in a residential nursery (2-36 months) to contact with their parents on a 24 hours test-re-test protocol evaluating relational withdrawal (ADBB 5 times) , salivary cortisol concentrations (8 times), index of difficult behaviour the day and the night before and after the visit. These variables have been studied in connection with the child's characteristics (age, development, gender, birth order), and those of the parent-child interaction (sensitivity, dyadic synchrony), of the visit (frequency, duration), of the placement (time, reason, age at placement), as well as with parental characteristics (age, depression, anxiety, sensitivity to evaluation, mental health, social support, traumatic experiences, attachment representations). Results: babies do react to parental contact. Three types of reactions have been identified: - babies who respond well to contact with their parents and suffer from separation. These babies have a better development, their parents are more sensitive than those of other groups and they enjoy the visits. Their cortisol levels drop to visit and rise back at separation. - Babies who react by more relational withdrawal in contact with their parents: these babies show no distress at separation. They appear better adapted to life in the institution (less relational withdrawal). Their parents are much less sensitive than the others. Their cortisol levels are generally high even during the visit. These babies are placed sooner than the other two groups. -Babies who show no reaction to contact with their parents in terms of relational withdrawal. They have generally lower concentrations of cortisol. They cannot be particularly distinguished from the other with regard of all characteristics that have been evaluated. This group appears at psychopathological risk since it shows a consistently high level of relational withdrawal associated with lower levels of salivary cortisol and lower reactivity of the HPA axis. The research also highlighted the effect of different variables on the baby's reactions to parental visit. The most important ones seem to be the quality of parent-child interaction, child development, and the characteristics of the placement and the visit. Various effects have been highlighted: - grief effect when returning from visit for children who have had good contact with their parents. - An anticipatory effect of stress of the visit for babies who react badly to contact with their parents. - A relief effect returning from visit for babies that react poorly to contact with their parents. - A contamination effect for some children the day after the visit, those babies belonging to the group of children who respond poorly to contact with their parents. - A positive effect of the visit for children who respond well in contact with parents. Results are discussed in relation to literature, and in terms forensic implications and of clinical and research applications of maintaining contact between babies and parents separated by placement in the field of child protection

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McCarthy, Christopher Darryl. « Visual contact estimation ». Phd thesis, 2010. http://hdl.handle.net/1885/150593.

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A fundamental capability of any navigation system is the perception of potential contact with surfaces in the environment. The efficiency and robustness of natural vision has motivated the development of biologically-inspired approaches to achieve this. Biological studies have highlighted the importance of visual motion (as perceived via optical flow) in the guidance of animal action. However, the use of optical flow in robot navigation systems remains problematic, impeded by measurement noise, environmental assumptions, and real-time constraints. This thesis proposes new biologically-inspired visual cues and algorithms for robust visual control and contact estimation from optical flow. We consider this primarily in the context of robot navigation and control. We present a robust strategy for docking a mobile robot with near-frontal surfaces using optical flow divergence. Results show improved robustness during egomotion, allowing closer than previously reported stopping distances. We present a strategy for performing controlled approaches towards surfaces of arbitrary orientation, providing the first unified control law for landing and docking. Velocity and heading control is achieved using only the maximum flow divergence on the view sphere. We present an insect-inspired structure-from-motion scheme using spherical optical flow from a hemispherical fish-eye sensor, providing the first demonstration of real-time depth map recovery from dense optical flow estimation. In dynamic environments, we investigate the use of optical flow to predict the time and location of impact of incoming objects. We consider this in the context of a stationary camera, as well as for on-road driver hazard perception assistance. We conclude that robustness in flow-based control schemes can be improved if system dynamics are handled in the image domain. This can be achieved by prioritising visual cues conveying a relationship between self-motion and scene structure over explicit structure-from-motion recovery in the control loop. Results suggest a wide-angle spherical projection model is well-suited for visual contact estimation from optical flow.

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Chen, Wen-Lin, et 陳玟伶. « Automated Inspection of Electric Contact Rivets UsingComputer Vision ». Thesis, 2007. http://ndltd.ncl.edu.tw/handle/58s3wm.

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碩士
國立臺北科技大學
工業工程與管理研究所
95
Electric contacts for switches, breakers and relays play a very important role in electric industry. In this paper, we propose an automated visual Inspection system for electric contact rivets using computer vision .The system is developed based-on spatial domain information of defects, and classifies the surface defects including cracks, breaks, and scratches. Furthermore, this study proposes a machine vision-based roundness measuring method that applies Particle Swarm Optimization Algorithm (PSO) , modified Hooke –Jeeves Pattern Search and Simulated annealing algorithms (SA) for computing the roundness measurement of maximum inscribing circle (MIC), minimum circumscribing circle (MCC). Experimental results show the modified Hooke –Jeeves Pattern Search-based method outperforms PSO-based method and SA-based method in both accuracy and the efficiency.

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Huang, Mei-Ling, et 黃美玲. « The vision contact under the sliding shelters：The container object of the vision layers ». Thesis, 2018. http://ndltd.ncl.edu.tw/handle/e6aads.

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碩士
國立臺南藝術大學
建築藝術研究所
106
Even imperfection, frailness, coward……are all part of us, we have been complete with them. Most of people in Taiwan prefer “science”, “statistics”, which can be quantified. But author think that there are many things so important for human being cannot be quantified, like emotion, taste, experience. This kind of social value makes people seldom talk about feelings, and it causes people to feel less and depress sentiments. It’s a great pity. Author think that our life consisted of every simple thing, feeling…If we against feeling emotion, then we reject a part of life. The author hope the work can remind people that emotion is essential for us. It can take us to find out the new vision of life. The art work is also the way for author to check herself during the studying process in Interbreeding Field. With several experiences of art collective creations, author learn the concepts of that the “Building” can be the way to make the art works, and also learn about how to feel the relations between human and surroundings. Then the author back to the place where the journey start, and create the art work with her own experience. The author trying to discuss her art work, which was created with the interplay between bodily perception and emotions and the creative techniques learned in these years in the paper. In the art space, the author using kinds of container objects to highlight the layers in the environment, with that visitors can find out the beauty they never pay attention in daily life. The container objects also build the peaceful space, and visitors can get rid of the values imposed by society, look back their life with different attitude and perspectives. Hope the sharing "I am who I am", can let the viewers find out and accept the true selves.

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Santos, Maria. « Visão Integrada do Contacto com Cliente numa Empresa da Indústria de Bebidas ». Dissertação, 2013. http://hdl.handle.net/10216/73728.

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Santos, Maria Teresa Alves Coelho dos. « Visão Integrada do Contacto com Cliente numa Empresa da Indústria de Bebidas ». Master's thesis, 2013. https://repositorio-aberto.up.pt/handle/10216/69411.

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Thèses sur le sujet « Contatto visivo »

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