Дисертації: "Stress visivo"

1

INAMA, MARCO. "Three-Dimensional vs Two-Dimensional Minimally Invasive Surgery. A comparison of the visual work load and surgical outcomes." Doctoral thesis, Politecnico di Torino, 2018. http://hdl.handle.net/11583/2710181.

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BACKGROUND Three-dimensional (3D) imaging, a recent technical innovation in laparoscopic surgery, has been introduced to enhance depth perception and facilitate operations. The clear benefit of the 3D laparoscopy has never been tested. Some concerns emerged regarding the possible negative effects over the visual system in those surgeons who performed 3D surgery every day. 3D laparoscopy has been validated both in “in-vitro” and “in-vivo” (clinical) settings. All survey done in laparoscopic simulator comparing surgical exercise (suturing, peg transfer, cutting) performed with 2D or 3D system reported better results in the second group, regardless the surgeon experience. Less data is disposable in the clinical setting, but with same conclusions. The use of 3D technology needs passive or active polarized glasses. Optometric tests, objective exams (RMN or EEG) and subjective questionnaires have been widely used to evaluate the alterations in the visual system utilizing the 3D technology. Each test concluded that 3D technology causes alteration in the EEG waves, but how long these alterations last is still unknown. AIM The aim of this study was to evaluate the possible benefit of using the 3D technology in terms of surgical outcomes (study 1) and to evaluate the alterations over the visual system operating in 3D laparoscopy (study 2). MATERIALS AND METHODS The study was a single-center prospective observational clinical trial, divided in two sub-study with a single patients-population. Participants included patients aged 18 years old and above, eligible for colorectal resections for neoplastic or inflammatory diseases. Four experienced surgeons in colorectal and laparoscopic surgery participated in the study. Each surgeon followed the standard laparoscopic surgical rules performing the different type of colorectal resection, regardless the study subgroup. Data were collected at the pre-operative clinic, during surgery, during the hospitalizations and at the short term follow-up (30th days). For each study, there was a primary endpoint: 1. Primary endpoint for Study 1: incidence of Clavien grade 3, 4 and 5 postsurgical complications in patients undergone 3D colorectal resection; 2. Primary endpoint for Study 2: to grade the visual work load of surgeons operating with 3D screens and glasses. At the end of each procedure (2D or 3D) the first surgeon had to fill in two different subjective questionnaire (the NASA task load index questionnaire and the Simulator Sickness questionnaire) to grade the visual sickness felt during the operation. RESULTS From January 2015 to September 2017, 313 patients were enrolled in the study: 82 in the 2D group, 231 in the 3D group. STUDY 1: Colorectal cancer was the main indication for surgery (n 235, 75.1%), followed by colonic diverticulosis, benign polyposis and inflammatory bowel diseases (IBD), respectively 43 (13.8 %), 25 (7.9 %) and 10 (3.2 %). Age, sex, ASA score were comparable between the two groups. The median operative time showed no statistically significant difference between the 3D and 2D groups (p 0.611). Less drains were positioned at the end of the 3D operations comparing with 2D procedures (p 0.013). The stapled anastomosis was the most frequent performed over other techniques. The other intra-operative findings showed no significant difference between the two study groups. The median hospitalization and the reoperation rate showed no difference between the two groups. STUDY 2: The statistical analysis done over all 313 cases divided in 2D and 3D did not reveled significant difference of the visual work scored by the NASA TLX. Data emerging from the SSQ questionnaire reveled no case of moderate or severe symptoms in both groups. CONCLUSIONS 3D laparoscopic surgery had the same postoperative results of the 2D standard laparoscopy. The more frequent intra-abdominal anastomosis in the 3D group might suggest a more safeness felt by the surgeon using the new technology. The NASA TLX and the SSQ questionnaire did not reveled significant difference of the visual work between 2D and 3D vision.

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2

Li, Hong. "College stress and psychological well-being : vision in life as a coping resource /." Hong Kong : University of Hong Kong, 2002. http://sunzi.lib.hku.hk/hkuto/record.jsp?B25017408.

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3

Yekta, Karizbala A. A. "The clinical significance of fixation disparity in binocular vision." Thesis, University of Bradford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.233694.

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4

Li, Hong, and 李虹. "College stress and psychological well-being: vision in life as a coping resource." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31243344.

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5

Nguyen, Cong Uy. "Hybrid stress visco-plasticity : formulation, discrete approximation, and stochastic identification." Thesis, Compiègne, 2022. http://www.theses.fr/2022COMP2695.

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Dans cette thèse, une nouvelle approche est développée pour les problèmes de viscoplasticité et de dynamique non linéaire. En particulier, les équations variationnelles sont élaborées selon le principe de Helligner-Reissner, de sorte que les champs de contrainte et de déplacement apparaissent comme des champs inconnus sous la forme faible. Trois nouveaux éléments finis sont développés. Le premier élément fini est formulé pour le problème axisymétrique, dans lequel le champ de contraintes est approximé par des polynômes d’ordre inférieur tels que des fonctions linéaires. Cette approche donne des solutions précises spécifiquement dans les problèmes incompressibles et rigides. De plus, un élément fini de flexion de membrane et de plaque est nouvellement conçu en discrétisant le champ de contraintes en utilisant l’espace vectoriel de Raviart-Thomas d’ordre le plus bas RT0. Cette approche garantit la continuité du champ de contraintes sur tout un domaine discret, ce qui est un avantage significatif dans la méthode numérique, notamment pour les problèmes de propagation des ondes. Les développements sont effectués pour le comportement constitutif visco-plastique des matériaux, où les équations d’évolution correspondantes sont obtenues en faisant appel au principe de dissipation maximale. Pour résoudre les équations d’équilibre dynamique, des schémas de conservation et de décroissance de l’énergie sont formulés en conséquence. Le schéma de conservation de l’énergie est inconditionnellement stable, car il peut préserver l’énergie totale d’un système donné sous une vibration libre, tandis que le schéma décroissant peut dissiper des modes de vibration à plus haute fréquence. La dernière partie de cette thèse présente les procédures d’upscaling du comportement des matériaux visco-plastiques. Plus précisément, la mise à l’échelle est effectuée par une méthode d’identification stochastique via une mise à jour baysienne en utilisant le filtre de Gauss-Markov-Kalman pour l’assimilation des propriétés importantes des matériaux dans les régimes élastique et inélastique
In this thesis, a novel approach is developed for visco-plasticity and nonlinear dynamics problems. In particular, variational equations are elaborated following the Helligner-Reissner principle, so that both stress and displacement fields appear as unknown fields in the weak form. Three novel finite elements are developed. The first finite element is formulated for the axisymmetric problem, in which the stress field is approximated by low-order polynomials such as linear functions. This approach yields accurate solutions specifically in incompressible and stiff problems. In addition, a membrane and plate bending finite element are newly designed by discretizing the stress field using the lowest order Raviart-Thomas vector space RT0. This approach guarantees the continuity of the stress field over an entire discrete domain, which is a significant advantage in the numerical method, especially for the wave propagation problems. The developments are carried out for the viscoplastic constitutive behavior of materials, where the corresponding evolution equations are obtained by appealing to the principle of maximum dissipation. To solve the dynamic equilibrium equations, energy conserving and decaying schemes are formulated correspondingly. The energy conserving scheme is unconditional stable, since it can preserve the total energy of a given system under a free vibration, while the decaying scheme can dissipate higher frequency vibration modes. The last part of this thesis presents procedures for upscaling of the visco-plastic material behavior. Specifically, the upscaling is performed by stochastic identification method via Baysian updating using the Gauss-Markov-Kalman filter for assimilation of important material properties in the elastic and inelastic regimes

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6

Crotogino, Jennifer. "Visual stress in migraine : subjective and psychophysiological responses to intense visual stimulation." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=38475.

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This dissertation assesses whether intense visual stimulation can act as a stressor to migraine sufferers between attacks, and whether subjective and psychophysiological reactions to these stimuli can clarify how migraine attacks may be triggered.
The first study assessed thresholds of light-induced discomfort and pain in migraine sufferers and non-migrainous controls during a non-headache period. Two instruction sets were compared to assess whether information presented to participants would affect thresholds. The results showed that migraineurs had significantly lower thresholds for light-induced pain. However, this effect was most apparent in those who had heard the negatively biased instructions reinforcing the need to control contextual factors when assessing subjective phenomena such as visual discomfort.
The second study assessed subjective and psychophysiological responses of female migraine sufferers and female controls during exposure to visual stimuli incorporating spatial and temporal characteristics that are most likely to be bothersome to migraineurs. Two control stimuli were included to assess responses during similar, but theoretically less aversive conditions. Migraine sufferers had higher heart rate and more frequent electrodermal responses than controls at all points of the study, including baseline and recovery. However, while migraineurs reported higher anxiety during the intense conditions, and reported more visual and somatic complaints than controls during various viewing conditions, they did not show heart rate, heart rate variability or electrodermal changes that would suggest clear changes in autonomic function in response to aversive visual stimulation.
The third study assessed ambulatory electrocardiograms to investigate whether autonomic changes would be evident in the period leading up to, during or following a migraine. Three individuals were assessed on a day when they experienced a naturally occurring headache, and on a day when they were not. No obvious pattern of autonomic change was detected before or after headache, although there was some evidence that a pattern of increased heart rate and decreased vagal tone may accompany headache.
In summary, the results confirm that migraine sufferers are more sensitive to intense visual stimulation than controls, but do not support the contention that exposure results in widespread autonomic changes. Since interictal visual discomfort is a common in migraine, further research is needed to clarify how it can be incorporated into models of migraine pathophysiology.

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7

Hill, N. J. "Visco-plastic and thermal stress analysis in the continuous casting of steel." Thesis, Teesside University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376088.

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8

GONZALES, GIANCARLO LUIS GOMEZ. "MEASUREMENT OF ELASTOPLASTIC STRAINS AT STRESS CONCENTRATION REGIONS USING MESHLESS METHODS AND COMPUTER VISION." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2014. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=24993@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO
A análise de deformações em torno de regiões de concentração de tensões é uma importante ferramenta na avaliação da integridade estrutural de peças e componentes mecânicos. Todavia, esta análise se torna mais complexa quando o material atinge a plastificação junto ao entalhe. Neste trabalho, uma nova metodologia numérico-experimental para medição de deformações na superfície de um material, combinando métodos sem malha e visão computacional, é apresentada. A parte experimental da técnica é baseada na captura de imagens de um material em estados diferentes de deformação durante um ensaio mecânico. A técnica de visão computacional conhecida como Scale Invariant Feature Tecnique (SIFT) é utilizada aqui para extrair pontos característicos nas imagens capturadas. Para tanto, uma textura aleatória foi pintada na superfície do corpo de prova. Em seguida, os deslocamentos são obtidos experimentalmente, através do seguimento das posições dos pontos SIFT corretamente correspondidos no par de imagens capturadas do ensaio, antes e depois da aplicação da carga. Os pontos fornecidos pelo algoritmo SIFT são selecionados como nós de uma formulação sem malha, e o método de mínimos quadrados móveis é utilizado para gerar uma aproximação numérica do campo de deslocamentos e as suas derivadas. Assim, deformações na região próxima ao entalhe são devidamente quantificadas para posterior análise. Na validação da metodologia proposta, corpos de prova entalhados foram utilizados para estudar o comportamento da deformação plástica nas regiões de concentração de tensões. Os resultados dos testes mostraram boa concordância e precisão quando comparados com soluções analíticas, simulações pelo método dos elementos finitos (ANSYS) e soluções obtidas através de um software comercial de correlação de imagens digitais.
Strain analysis near stress concentration regions is an important tool for structural integrity of mechanical components. However, this analysis becomes more complex when the material starts to deform plastically near the notch root. In this work, a novel experimental-numerical technique for the measurement of the strain distribution on the surface of a deformable body is described, which uses meshless methods and computer vision. The experimental part of this technique is based on the capture of images at different stages of material deformation during a mechanical test. The Scale Invariant Feature Transform (SIFT) is a computer vision algorithm used here to extract distinctive points or features in the captured images. For this purpose, a random texture was painted on the specimen surface. Then, the displacements are experimentally obtained by tracking the positions of successfully matched SIFT points in an undeformeddeformed pair of images. The points provided by SIFT are selected as nodes in a meshless formulation and the moving least square method is used to generate a numerical approximation for the displacement field and its derivates. Thus, the corresponding strain field close to the notch is calculated. To validate the proposed methodology, notched specimens were employed to study the deformation behavior on regions of stress concentration. Experimental results showed good agreement and accuracy when compared to analytical solutions, to simulations by finite elements (ANSYS) and to solutions obtained by using a commercial software based on the digital image correlation technique.

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9

Greenwood, Verity Jane. "The effects of the artificial light environment on avian behaviour and physiological indicators of stress." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274670.

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Lyra, Cassandra Santantonio de. "A aromaterapia científica na visão psiconeuroendocrinoimunológica: um panorama atual da aromaterapia clínica e científica no mundo e da psiconeuroendocrinoimunologia." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/47/47134/tde-11032010-103420/.

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Esse estudo é um estudo teórico, baseado em revisão bibliográfica. Ele objetivou a construção de um panorama conceitual da aromaterapia, considerandose sua história e desenvolvimento, além de propor um modelo integrativo dos aspectos fisiológicos e psicossociais com base nas premissas psiconeuroendocrinoimunológicas. Aromaterapia é uma prática milenar, que passou por diversas mudanças ao longo da história e por esse motivo, atualmente, apresentase conceitualmente confusa e imprecisa. Seu ressurgimento nos anos 30 permitiu um início da visão científica do assunto, que, no entanto, evoluiu lentamente pelas dificuldades metodológicas encontradas. A organização do panorama atual dessa terapia permitiu observar que existem muitos países que estudam a aromaterapia, no entanto, com abordagens e visões distintas, de modo que tornase complexa a intersecção dos estudos. No seu estudo científico diversos elementos devem ser aqui considerados, como tipo de estudo (teórico, préclínico ou clínico), variáveis a serem controladas (farmacológicas, dos sujeitos e de procedimento) e questões abordadas (quanto ao efeito dos óleos essenciais, quanto aos seus mecanismos de ação e quanto à influência das variáveis em ambos). Além disso, atualmente existem diversas abordagens: filosófica (baseada em filosofias de saúde orientais), psicológica (baseada no conceito de memória olfativa), farmacoquímica (baseada em farmacologia e química dos óleos essenciais), neurológica (baseada nas neurociências) e psiconeuroendocrinoimunológica (baseada na psiconeuroendocrinoimunologia). Esse trabalho se focou nos estudos préclínicos e clínicos de aromaterapia, a partir de uma visão psiconeuroendocrinoimunológica. A fim de servir como um passo inicial à padronização científica do assunto, foi proposto uma definição mais objetiva de aromaterapia, a partir da qual o trabalho foi desenvolvido. Dentro do modelo psiconeuroendocrinoimunológico, a aromaterapia pode ter efeitos diretos ou indiretos nos sistemas nervoso, endócrino, imune e psicológico, sendo esses efeitos tanto fisiológicos quanto psicológicos e dados por mecanismos de ação farmacológicos e olfativos. Os aromas sempre têm efeitos farmacológicos, independente da via de aplicação utilizada, no entanto, quando se utiliza a via inalatória, são acrescidos a esses efeitos farmacológicos os efeitos olfativos, que são próprios do sistema olfativo e diferenciados. O estudo do olfato é indispensável para o entendimento científico da aromaterapia e ele tem se desenvolvido amplamente, apesar de que ainda existem muitos elementos a serem esclarecidos. Com isso, os estudos na área da aromaterapia científica tem evoluído cada vez mais, permitindo estudos mais minuciosos e conclusivos a respeito do funcionamento dos óleos essenciais no organismo e na mente. Um caminho pra esses estudos, dentro do modelo psiconeuroendocrinoimunológico, é o estudo da relação entre aromaterapia e stress. A premissa básica da teoria de stress é estudar a integração do corpo e da psique. Esse estudo concluiu que a psiconeuroendocrinoimunologia é um modelo útil para estudar a aromaterapia, por permitir o seu estudo científico integrando seus efeitos fisiológicos e psicológicos, e que a organização realizada permitiu uma fundamentação teórica para a elaboração, em futuros projetos na área, de métodos científicos em aromaterapia, stress e psiconeuroendocrinoimunologia.
This is a theoretical study, based on bibliographical revision. It aimed to build a conceptual panorama of aromatherapy, considering it\'s history and development, and also propose an integrative model of the physiological and psychosocial aspects, based on the psychoneuroendocrineimmunological premisses. Aromatherapy is a millenarian practice, that suffered many changes throughout history, and, for this reason, nowadays, it is confusing and uncertain. It\'s reappearance in the 30\'s permitted a start of the scientific view of the theme. However, the scientific view evolved slowly because of the methodological difficulties that were found. The organization of the current panorama of this therapy permitted observing that many countries study aromatherapy. However, there are many different approaches and views of the subject, in a way that it\'s complex to do the intersection of the studies. In it\'s scientific study there are many elements to be considered, such as type of study (theoretical, preclinical or clinical), variables to control pharmacological, subject and procedural) and questions studied (about the effects of essential oils, about their action mechanisms and about the influence of the variables on both). Furthermore, currently there are many approaches to the study: philosophical (based on oriental heath philosophy), psychological (based on the concept of olfactory memory), pharmacochemical (based of pharmacology and essential oil chemistry), neurological (based on neuroscience) and psychoneuroendocrineimmunological (based on psychoneuroendocrineimmunology). This work focused on preclinical and clinical studies, from a psychoneuroendocrineimmuneological point of view. In order to serve as a first step to the scientific standardizing of the subject, a more objective definition of aromatherapy was proposed, from which the study developed the subject. In the psychoneuroendocrineimmunological model, aromatherapy may have direct or indirect effects in the nervous, endocrine, immune and psychological systems. These effects can be physiological and psychological and they are caused by pharmacological and olfactory mechanisms. Aromas always have pharmacological effects, independently from application via, but when the inhalation is used the olfactory effects are added to these pharmacological effects. The olfactory effects are different from the others and characteristic of the olfactory system. The study of olfaction is indispensable to the scientific understanding of aromatherapy and it has evolved immensely, although there are still many elements still to be understood. Consequently, the studies in aromatherapy also have evolved more, permitting more minute and conclusive studies about the functioning of essential oils in the organism and mind. A path to this kind of study, in the psychoneuroendocrineimmunological model, is the study of the interaction between aromatherapy and stress. The basic premiss of the theory of stress is to study the integration of body and mind. This study concluded that psychoneuroendocrineimmunology is a useful model to study aromatherapy because it permits the scientific evaluation of both physiological and psychological effects of aromatherapy. It also concluded that the organization of the current panorama permitted a theoretical foundation for elaboration of scientific methods in aromatherapy, stress and psychoneuroendocrineimmunology in future studies.

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Weber, Darren Lee, and darrenleeweber@gmail com. "EVENT-RELATED POTENTIAL INDICES OF ATTENTION AND MEMORY IN POST-TRAUMATIC STRESS DISORDER." Flinders University. Psychology, 2004. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20070702.080042.

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Background Previous reports of abnormal auditory N2 and P3 event-related potentials (ERPs) suggest impaired discrimination, evaluation or context updating for infrequent target stimuli in post-traumatic stress disorder (PTSD). This study examines each of these processes by investigating high-resolution ERP topography during target detection for visual word stimuli. Method ERPs were recorded at 124 electrodes from 10 PTSD patients and 10 matched controls. Target detection tasks comprised blocks of equally probable red and blue words, with low probability target events. Detection of fixed target words in one color provided the basis for measurement of selective attention for color, stimulus evaluation and target detection processing. Alternative task instructions, with the same stimuli, required detection of any consecutive word repeats in an attended color, which demands working memory updating for nontarget words. Comparison of attended non-target words from each task indicates the extra activity for updating working memory representations of target attributes. Thus, specific condition comparisons provide measures of stimulus discrimination and evaluation, working memory updating and target detection. Results PTSD patients had slower and less accurate motor responses in both tasks, with greater inaccuracy during the variable target task. There was abnormal ERP activity in PTSD at 200-300 ms in the left posterior temporal region during stimulus discrimination and target recognition. During evaluation of attended non-target words, PTSD patients demonstrate deficits in frontal and parietal regions at 400-500 ms. During working memory updating, at 400-600 ms, there was a delay in frontal activation, followed by smaller activity in parietal areas in PTSD. During target word recognition, PTSD patients demonstrate deficits in frontal activity, with greater occipital and parietal activity. Conclusions These findings indicate impaired evaluation and integration of new information in working memory. In particular, the results suggest failure in frontal executive systems, with greater dependence on visual processing for effective target detection. The current findings are consistent with neuropsychology studies that identify deficits of attention and memory for verbal information in PTSD. This study provides insight into the temporal components of attention and working memory in PTSD. It is proposed that working memory deficits arise from disruption to synchronized activity in distributed networks engaged in working memory processes.

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Andersen, Mark Bille. "Psychosocial factors and changes in peripheral vision, muscle tension, and fine motor skills during stress." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184446.

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A theoretical model of stress and athletic injury is presented. The purpose of the dissertation is to propose a comprehensive framework of the stress-injury relationship that includes cognitive, physiological, attentional, behavioral, intrapersonal, social, and stress history variables. Development of the model grew from a synthesis of the stress-illness, stress-accident, and stress-injury literatures. The model and its resulting hypotheses offer a framework for many avenues of research into the nature of injury and reduction of injury risk. Other advantages of the model are that it addresses possible mechanisms behind the stress-injury relationship and it suggests several specific interventions that may help diminish the likelihood of injury. The model also has the potential to be applied to the investigation of injury and accident occurrence in general. A portion of the model is then tested experimentally. Personality, stress, and coping resource variables are used to predict changes in peripheral vision, general muscle tension, heart rate, state anxiety, and fine motor skill (a hand steadiness task) from baseline to stress condition (a dual-task paradigm with noise as an added stressor). There were significant decreases in peripheral vision and hand steadiness accompanied by significant increases in state anxiety and heart rate from baseline to stress conditions. The only significant predictor variable for peripheral vision changes was negative life events. Subjects with high negative life events ratings had greater peripheral vision deficits during stress than subjects who rated low on negative life events. For increases in state anxiety only the self report of how the subject experienced the stress condition was significant. Subjects who rated the stress condition as stressful had greater state anxiety increases than subjects who rated the stress condition as challenging. The results are discussed in terms of future directions for stress-injury research.

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Movsisyan, Tatevik. "Perceived Stress and Visual Function in Macular Degeneration Patients." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461087205.

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Panwar, Anurag. "Determining the Effectiveness of Soil Treatment on Plant Stress using Smart-phone Cameras." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6346.

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Plants are vital to the health of our biosphere, and effectively sustaining their growth is fundamental to the existence of life on this planet. A critical aspect, which decides the sustainability of plant growth is the quality of soil. All other things being fixed, the quality of soil greatly impacts the plant stress, which in turn impacts overall health. Although plant stress manifests in many ways, one of the clearest indicators are colors of the leaves. In this thesis, we conducted an experimental study in a greenhouse for detecting plant stress caused by nutrient deficienceies in soil using smartphone cameras, coupled with image processing and machine learning algorithms. The greenhouse experiment was conducted by growing two plant species; willows (Salix Pentandra) and poplars (Populus deltoides x nigra, DN34), in two treatments. These treatments included: unamended tailings (collected from a lead mine tailings pond and characterized by nutrient deficiency), and biosolids amended tailings. Biosolids are very rich in nutrients and were added to the tailings in one of the two treatments to supply plants with nutrients. Subsequently, we captured various images of plant leaves grown in both soils. Each image taken was pre-processed via filteration to remove associated noise, and was segmented into pixels to facilitate scalability of analysis. Subsequently, we designed random forests based algorithms to detect the stress of leaves as indicated by their coloring. In a dataset consisting of 34 leaves, our technique yields classifications with a high degree of prediction, recall and F1 score. Our work in this thesis, while restricted to two types of plants and soils, can be generalized. We see applications in the emerging area of urban farming in terms of empowering citizens with tools and technologies for enhancing quality of farming practices.

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Vine, Samuel James. "Anxiety, attention and performance variability in visuo-motor skills." Thesis, University of Exeter, 2010. http://hdl.handle.net/10036/118107.

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The aims of the current program of research were to examine the impact of anxiety on performance and attentional control during the execution of two far aiming tasks, and to examine the efficacy of gaze training interventions in mediating these effects. Attentional control theory (ACT), which suggests that anxious individuals have impaired goal-directed attentional control, was adopted as a theoretical framework, and the Quiet Eye, characterised by long final fixations on relevant locations, was adopted as an objective measure of overt attentional control. In Studies 1 and 2 increased pressure impaired goal directed attentional control (QE) at the expense of stimulus-driven control (more fixations of shorter duration to various targets). The aim of studies 3 and 4 was therefore to examine the efficacy of an intervention designed to train effective visual attentional control (QE training) for novices, and determine whether such training protected against attentional disruptions associated with performing under pressure. In both studies the QE trained group maintained more effective visual attentional control and performed significantly better in a subsequent pressure test compared to the Control group, providing support for the efficacy of attentional training for visuo-motor skills. The aim of study 5 was to examine the effectiveness of a brief QE training intervention for elite golfers and to examine if potential benefits shown for novices in studies 3 and 4 transferred to competitive play. The QE-trained group maintained their optimal QE and performance under pressure conditions, whereas the control group experienced reductions in QE and performance. Importantly, these advantages transferred to the golf course, where QE-trained golfers reduced their putts per round by 1.9 putts, compared to pre-training, whereas the control group showed no change in their putting statistics. This series of studies has therefore implicated the role of attention in the breakdown of performance under pressure, but has also suggested that visual attentional training regimes may be a useful technique for alleviating this problem.

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Oliveira, Artur André Almeida de Macedo. "INvestigate and Analyse a City - INACITY." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/45/45134/tde-04052018-170132/.

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Este trabalho apresenta uma plataforma para coleta e análise de imagens urbanas, que integra Interfaces de Programação de Aplicativos \"Application Programming Interfaces\" (APIs) de sistemas de busca de imagens, Sistemas de Informações Geográficas (SIGs), mapas digitais e técnicas de visão computacional. Esta plataforma, INACITY, permite que usuários selecionem regiões de interesse e capturem elementos de relevância para a arquitetura urbana, como, por exemplo árvores e buracos em ruas. A implementação da plataforma foi feita de maneira a permitir que novos módulos possam ser facilmente incluídos ou substituídos possibilitando a introdução de outras APIs de mapas, SIGs e filtros de Visão Computacional. Foram realizados experimentos com as imagens obtidas através do \"Google Street View\" onde árvores são capturadas em áreas de bairros inteiros em questão de minutos, um ganho significativo quando comparado com o procedimento manual para levantamento deste tipo de dado. Além disso, também são apresentados resultados comparativos entre os métodos de visão computacional propostos para a detecção de árvores em imagens com outros métodos heurísticos, em um conjunto onde as árvores estão marcadas manualmente e assim as taxas de precisão e de redescoberta de cada algoritmo podem ser avaliadas e comparadas.
This project presents a platform that integrates Application Programming Interfaces (APIs), image retrieval systems, Geographical Information Systems (GISes), digital maps and Computer Vision techniques to collect and analyse urban images. The platform, INACITY (an acronym for INvestigate and Analyse a City), empowers users allowing them to select a region over a map and see urban features inside that region that have relevance to the urban architecture context, for instance trees. The implementation is extensible and it is designed to make it easy to add or replace new modules, for instance, to add a new API to present a map, different GISes and other Computer Vision filters.

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17

Lindblom, Emelie. "The effect of visual barriers, outdoor housing and feeding enrichment on the behaviour of drills (Mandrillus leucophaeus) at Parken Zoo." Thesis, Linköpings universitet, Biologi, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-114632.

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Animals are confronted with potential stressors at zoos compared to in the wild, such as visitors and lack of environmental stimulation. This study included two projects conducted on the drills at Parken Zoo in Eskilstuna where I investigated: 1) the effect of visual barriers on the behaviour of the drills and if the visual barriers can moderate the visitor effect on the drills and 2) how outdoor-only access together with feeding enrichment (frozen fruit and tube feeders) affects the behaviour of the drills. 1/0- sampling method was used when observing the behaviours of the drills with 1 minute-intervals. Resting/Sleeping increased, while social agonistic behaviour and stereotypies decreased with visual barriers. A moderated visitor effect was shown in resting/sleeping and social affiliative behaviour in the drills with visual barriers. However, social agonistic behaviour and visitor interaction were still affected by visitors after the installation of the visual barriers, implying that the drills still find visitors stressful to some extent and that further alterations on the observation area viewing the indoor enclosure is recommended for the welfare of the drills. With outdoor-only access together with feeding enrichment, locomotion, foraging/eating and body-shaking increased, while resting/sleeping, social affiliative and agonistic behaviour, stereotypies, visitor interaction, scratching and self-grooming decreased. This suggests that outdoor-only access and feeding enrichment improve the behaviour of the drills and would be a valid option during summer season for the drills at Parken Zoo.

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18

Bons, Daniel. "Modelling peripheral vision in dynamic situations." Thesis, Linköpings universitet, Institutionen för medicinsk teknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-158641.

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Metamers of the ventral stream is a model which tries to describe what information we gather from our visual field. It have previously only been tested on static images. This thesis have continued the research and applied it to dynamic images in order to investigate if the model can be seen as a functional representation of our visual field. The results show that the model, at this stage, can not be seen as a fully functional representation of the visual field, but it can be used to determine the detectability of objects in the periphery. It also shows that what we humans perceive as motion is, at least to some extent, merely a change of the statistics in our visual field.

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19

Grainger, David. "Funnel Vision." VCU Scholars Compass, 2008. http://scholarscompass.vcu.edu/etd/966.

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This paper will talk about the videos and sculptural installation in my thesis exhibition. Shooting videos outside of the studio developed into a project overarching any individual video or its particular signs. Thus, this paper will focus on the video project with examples that follow a timeline of development, rather than the actual 6 videos on display in the exhibit. The two-part sculpture "Deer in the Headlights" is created in the context of these videos, and coexists with them in a specific architectural space. This space, as well as the clichéd meaning of the deer's gaze, have a relation to the title of the show.

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Navarro, Martina. "Efeitos de estresse e treino na latência e acurácia de respostas motoras a estímulos visuais." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/42/42137/tde-20092013-090421/.

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A presente tese investigou os efeitos de estresse na latência e acurácia de respostas motoras a estímulos visuais, e a eficiência de treino na reversão de tais efeitos. O embasamento teórico adotado foi o Attentional Control Theory, que prediz que em situações de estresse, o sistema atencional goal-directed fica prejudicado e sobrepujado pelo sistema stimulus-driven. O pênalti no futebol foi adotado como paradigma experimental. Os resultados revelaram que quando estressados participantes ou precisaram de mais tempo para responder ao estímulo visual ou eram incompetente em inibir respostas automáticas incompatíveis com a tarefa. Tais efeitos foram em parte revertidos com sucesso, revelando grandes diferenças individuais que parecem estar relacionadas com controle atencional. Os resultados também revelaram que a simples presença de um estímulo irrelevante para tarefa prejudicou a resposta motora. Os achados ofereceram uma melhor compreensão de como estresse e estímulos irrelevantes afetam o controle motor e de como treinamento pode reverter tais efeitos.
The current thesis investigated the effects of high-pressure on latency and accuracy of motor responses to visual stimuli and the efficiency of task-specific practice in managing these effects. The theoretical framework adopted was Attentional Control Theory, which argues that high-pressure increases stress and thus impairs the goal-directed attentional system. The penalty kick in football was adopted as paradigm. The experiments revealed that when stressed, participants either required more time to respond to the visual stimulus movement or were unable to inhibit automatic responses, resulting in consistent errors. Such effects were in part successfully reverted, revealing individual differences that seem to relate to the individuals tendencies for attentional control. Furthermore, the results showed that the mere presence of a threatening non-target object impaired shooting accuracy. The findings provide a better understanding of how high-pressure and non-target objects affect motor performance and how task-specific practice may revert such effects.

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Trogadas, Giorgos, and Larissa Ekonoja. "The effect of noise filters on DVS event streams : Examining background activity filters on neuromorphic event streams." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-302514.

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Image classification using data from neuromorphic vision sensors is a challenging task that affects the use of dynamic vision sensor cameras in real- world environments. One impeding factor is noise in the neuromorphic event stream, which is often generated by the dynamic vision sensors themselves. This means that effective noise filtration is key to successful use of event- based data streams in real-world applications. In this paper we harness two feature representations of neuromorphic vision data in order to apply conventional frame-based image tools on the neuromorphic event stream. We use a standard noise filter to evaluate the effectiveness of noise filtration using a popular dataset converted to neuromorphic vision data. The two feature representations are the best-of-class standard Histograms of Averaged Time Surfaces (HATS) and a simpler grid matrix representation. To evaluate the effectiveness of the noise filter, we compare classification accuracies using various noise filter windows at different noise levels by adding additional artificially generated Gaussian noise to the dataset. Our performance metrics are reported as classification accuracy. Our results show that the classification accuracy using frames generated with HATS is not significantly improved by a noise filter. However, the classification accuracy of the frames generated with the more traditional grid representation is improved. These results can be refined and tuned for other datasets and may eventually contribute to on- the- fly noise reduction in neuromorphic vision sensors.
Händelsekameror är en ny typ av kamera som registrerar små ljusförändringar i kamerans synfält. Sensorn som kameran bygger på är modellerad efter näthinnan som finns i våra ögon. Näthinnan är uppbyggd av tunna lager av celler som omvandlar ljus till nervsignaler. Eftersom synsensorer efterliknar nervsystemet har de getts namnet neuromorfiska synsensorer. För att registrera små ljusförändringar måste dessa sensorer vara väldigt känsliga vilket även genererar ett elektroniskt brus. Detta brus försämrar kvalitén på signalen vilket blir en förhindrande faktor när dessa synsensorer ska användas i praktiken och ställer stora krav på att hitta effektiva metoder för brusredusering. Denna avhandling undersöker två typer av digitala framställningar som omvandlar signalen ifrån händelsekameror till något som efterliknar vanliga bilder som kan användas med traditionella metoder för bildigenkänning. Vi undersöker brusreduseringens inverkan på den övergripande noggrannhet som uppnås av en artificiell intelligens vid bildigenkänning. För att utmana AIn har vi tillfört ytterligare normalfördelat brus i signalen. De digitala framställningar som används är dels histogram av genomsnittliga tidsytor (eng. histograms of averaged time surfaces) och en matrisrepresentation. Vi visar att HATS är robust och klarar av att generera digitala framställningar som tillåter AIn att bibehålla god noggrannhet även vid höga nivåer av brus, vilket medför att brusreduseringens inverkan var försumbar. Matrisrepresentationen gynnas av brusredusering vid högre nivåer av brus.

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Kaloskampis, Ioannis. "Recognition of complex human activities in multimedia streams using machine learning and computer vision." Thesis, Cardiff University, 2013. http://orca.cf.ac.uk/59377/.

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Modelling human activities observed in multimedia streams as temporal sequences of their constituent actions has been the object of much research effort in recent years. However, most of this work concentrates on tasks where the action vocabulary is relatively small and/or each activity can be performed in a limited number of ways. In this Thesis, a novel and robust framework for modelling and analysing composite, prolonged activities arising in tasks which can be effectively executed in a variety of ways is proposed. Additionally, the proposed framework is designed to handle cognitive tasks, which cannot be captured using conventional types of sensors. It is shown that the proposed methodology is able to efficiently analyse and recognise complex activities arising in such tasks and also detect potential errors in their execution. To achieve this, a novel activity classification method comprising a feature selection stage based on the novel Key Actions Discovery method and a classification stage based on the combination of Random Forests and Hierarchical Hidden Markov Models is introduced. Experimental results captured in several scenarios arising from real-life applications, including a novel application to a bridge design problem, show that the proposed framework offers higher classification accuracy compared to current activity identification schemes.

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Oliva, Aravena Cesar Jaime. "Efeitos do estresse fisico no processamento das informações visuais perifericas em motoristas do transporte coletivo urbano." [s.n.], 1998. http://repositorio.unicamp.br/jspui/handle/REPOSIP/274880.

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Orientador: Jorge Sergio Perez Gallardo
Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Educação Fisica
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Resumo: O presente estudo teve como objetivo investigar os efeitos do estresse físico no processamento das informações visuais periféricas em motoristas do transporte coletivo urbano, os quais foram classificados de acordo com seu tempo de experiência como motoristas profissionais: -5 anos, 5-10 anos e +1Oanos de experiência. Participaram da pesquisa 30 motoristas das cidades de Concepción e Talcahuano, Chile, selecionados de forma aleatória, os quais foram divididos sem três grupos de 10 indivíduos segundo seus tempos de experiência. O campo visual do motorista foi medido em um laboratório com uma luminosidade de 1.500 luxo. A situação experimental consistiu na formação de um campímetro de 1900no eixo horizontal. A tarefa dos motoristas foi pedalar numa bicicleta ergométrica, na qual foram aplicadas três cargas crescentes (leve, submáxima, máxima) de 3 minutos cada uma. Os motoristas foram orientados para detectar e reconhecer os estímulos luminosos (lâmpadas coloridas de 12v, 4w) que apareciam no campo visual periférico, mediante sua visão binocular, sem movimento de olhos e/ou cabeça. Para determinara homogeneidade da amostragem fizeram se uma anamnese geral, um exame oftalmológico e um exame de campimetria dinâmica, pois os indivíduos que participaram do estudo deviam ter visão normal sem correções. Para determinar as cargas de trabalho, realizaram-se, primeiramente,um teste de telemetria para conhecer a resposta cardíaca destes no lugar de trabalho e, num segundo momento, foi realizado um teste de esforço. Para a coleta de dados foi construído um sistema eletromecânico, complementado por um microcontrolador Little Star, que permitiu comandar os estímulos luminosos periféricos de forma que os motoristas pudessem responder de acordo com a sua sensibilidade de percepção visual, enquanto pedalavam na bicicleta ergométrica Com base na análise de variância com medidas repetidas os dados permitem afirmar que existem diferenças estatísticas (p < 0,05) em relação ao tempo de experiência dos grupos e da carga, na decisão perceptiva da detecção. Quanto ao reconhecimento, também revelou diferenças estatísticas em relação à carga (p < 0,05) e interação grupo-carga (p < 0,01). O estudo mostrou, por meio da análise estatística do teste qui-quadrado (X2), que não existe diferença estatística (p > 0,05) no número de erros de detecção e reconhecimento, dependendo do tempo de experiência. Também se verificou, por meio da análise estatística de Friedman (X2p), que as cargas crescentes de trabalho têm influência significativa (p < 0,01) nas decisões perceptuais de detecção e reconhecimento dos indivíduos categorizados como motoristas
Abstract: The present study had as its objective to investigate the effects of physical stress in the peripheric visual information processing in drivers from urban collective transportation, which were classified according to their time of experience as professional drivers: -5 years, 5-10 years and +10years experience. Thirty drivers from the cities of Concepción and Talcahuano, Chile, participated of the research, being selected at random. They were divided in three groups of ten individuals each, according to their time of experience. The drivers' field of view was measured in a laboratory with a luminosity of 1.500 lux. The experimental situation consisted in the formation of a perimeter of 1900on the horizontal axle. The drivers' task was pedaling an ergonometer bicycle where three increasing loads were applied to (Iight, sub-maximum and maximum) of 3 minutes each. The driver ware oriented to detect and recognize the luminous stimulus (color lamps: 12v, 4w) which appeared in the peripheral field of view through his binocular vision, with no movement Itom the eyes and / or the head. To determine the homogencity of the sample, it were applied a general valuation, an ophthalmologic examination and a dinamic campimeter examination, because the individual who participed of the study should have normal vision without corrections. To determine the work loads, it ware first applied a telemeter test to know his cardiac answer in the place of work and, in a second moment, an effort test was aceomplished. For the data colleetion, an electromechanical system was built, complemented by a Little Star miero eontroler wich allowed to command the peripheral lurninous stimulus in sueh a . way that the drivers could answer,aceordingto their visualcperceptioncsensibility while pedaling an ergonometer bicycle. With base in analysis of variation with repeated measures the data allow to affirro that there are statistieal differences (p < 0,05) respeeting the time of experience of the group and the load in the perceptible decision of the detection. The recognition also revealed statistieal differenees respeeting the loads (p < 0,05) and group-Ioad interaction (p < 0,01). The study showed through the statistical analysis of the Chi Squared test (X2) the there is not a statistieal differenee (p > 0,05), in the number of deteetion and recognition mistakes depending on the time experienee. It was also eheeked through the statistieal analysis of Friedman (X2p) that the inereasing loads of work have significant influence (p < 0,01) in the perceptible decision of detection and recognition of the individuals categorized as drivers
Doutorado
Doutor em Educação Física

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24

Gholami, Mohammad. "Shear Induced Migration of Particles in a Yield Stress Fluid." Ohio University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1502793185991791.

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25

Reynolds, Michael. "The theatrical vision of Count Harry Kessler and its impact on the Strauss-Hofmannsthal partnership." Thesis, Goldsmiths College (University of London), 2014. http://research.gold.ac.uk/10559/.

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Count Harry Kessler (1868–1937) was an intimate of Hugo von Hofmannsthal and a friend of Richard Strauss. Kessler’s early exposure to European literature and works of music theatre, and the extensive network of theatre contacts that he made, combined with his appreciation of art, gave him a particular theatrical vision that impacted on two stage works by the Strauss-Hofmannsthal partnership: the opera Der Rosenkavalier (1911) and the ballet Josephs Legende (1914). The thesis traces, in particular, the derivation of Der Rosenkavalier from a French opérette, L’Ingénu libertin (1907) by Louis Artus and Claude Terrasse, which Kessler (alone of the three partners) had seen. The dramatic and musical structure of this work is analysed and compared with the work that it went on to inspire. The thesis concludes that Kessler’s theatrical vision was a major component in the architecture and dramatic structure of both Der Rosenkavalier and Josephs Legende, and that he should be recognised as fully as one of the three co-creators of the former work, as he has already been of the latter.

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Jack, Dominic. "Deep learning approaches for 3D inference from monocular vision." Thesis, Queensland University of Technology, 2020. https://eprints.qut.edu.au/204267/1/Dominic_Jack_Thesis.pdf.

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This thesis looks at deep learning approaches to 3D computer vision problems, using representations including occupancy grids, deformable meshes, key points, point clouds, and event streams. We focussed on methods targeted towards medium-sized mobile robotics platforms with modest computational power on board. Key results include state-of-the-art accuracies on single-view high resolution voxel reconstruction and event camera classification tasks, point cloud convolution networks capable of performing inference an order of magnitude faster than similar methods, and a 3D human pose lifting model with significantly fewer floating point operations and learnable weights than baseline deep learning methods.

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Story, David Lee Jr. "Autonomous Multi-Sensor and Web-Based Decision Support for Crop Diagnostics in Greenhouse." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/306925.

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An autonomous machine vision guided plant sensing and monitoring system was designed and constructed to continuously monitor plant related features: color (red-green-blue, hue-saturation-luminance, and color brightness), morphology (top projected canopy area), textural (entropy, energy, contrast, and homogeneity), Normalized Difference Vegetative Index (NDVI) (as well as other similar indices from the color and NIR channels), and thermal (plant and canopy temperature). Several experiments with repeated water stress cycles, using the machine vision system, was conducted to evaluate the machine vision system's performance to determine the timeliness of induced plant water stress detection. The study aimed at identifying significant features separating the control and treatment from an induced water stress experiment and also identifying, amongst the plant canopy, the location of the emerging water stress with the found significant features. Plant cell severity had been ranked based on the cell's accumulated feature count and converted to a color coded graphical canopy image for the remote operator to evaluate. The overall feature analysis showed that the morphological feature, Top Projected Canopy Area, was found to be a good marker for the initial growth period while the vegetation indices (ENDVI, NDVIBlue, and NDVIRed) were more capable at capturing the repeated stress occurrences during the various stages of the lettuce crop. Furthermore, the crop's canopy temperature was shown to be a significant and dominant marker to timely detect the water stress occurrences. The graphical display for the remote user showed the severity of summed features to equal the detection of the human vision. Capabilities and limitations of the developed system and stress detection methodology were documented with recommendations for future improvements for the crop monitoring/production system. An example web based decision support platform was created for data collection, storage, analysis, and display of the data/imagery collected for a remote operator.

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Nguyen, Dang Dan. "Revêtements polymères sous contraintes environnementales couplées." Phd thesis, Université de La Rochelle, 2012. http://tel.archives-ouvertes.fr/tel-01065519.

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L'objectif de notre étude est de mettre en évidence les synergies existantes entre les différents facteurs de vieillissement lors de la dégradation d'un revêtement polymère modèle, représentatif d'une peinture anticorrosion.Notre travail a consisté à suivre le vieillissement hygrothermique du système DGEBA/TETA sous forme de film libre et de revêtement déposé sur substrat acier dans différentes solutions (eau pure et NaCl 3%) pour différentes températures et contraintes mécaniques visco-élastique appliquées. Nos résultats ont montré que le programme de cuisson affectait les propriétés physico-chimiques et mécaniques du système initial et que l'absorption d'eau, non homogène, suivait une loi non-Fickienne, suite à un phénomène de gonflement.La prise en eau et la diffusion ont été caractérisées par gravimétrie et spectroscopie d'impédance électrochimique. Nos résultats montrent que les propriétés barrière du revêtement diminuent avec la quantité d'eau absorbée et avec la température de vieillissement. Cependant, la contrainte plane appliquée sur le système tend à contrarier cet effet. La formalisation de nos observations expérimentales dans le cadre d'une approche thermodynamique a montré l'effet prépondérant de la partie entropique par rapport à la partie enthalpique de l'énergie d'activation des processus de transport de l'eau, en raison de l'orientation des chaînes sous l'action de la contrainte. De plus, une diminution de la permittivité relative du revêtement sec a été observée en fonction de la température et de la contrainte appliquée, indépendamment de son signe (tension ou compression). Dans ce cas, la contribution enthalpique semble être prépondérante.

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Foulder-Hughes, Lynda Ann. "Motor function, vision, and growth, in main stream school children born at or below 32 weeks' gestation." Thesis, University of Liverpool, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369049.

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Rodrigues, Cláudio Roberto Barbosa Simões. "Contribuições ao uso de diodos emissores de luz em iluminação pública." Universidade Federal de Juiz de Fora, 2012. https://repositorio.ufjf.br/jspui/handle/ufjf/1695.

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Анотація:

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No intuito de aportar contribuições ao uso de diodos emissores de luz (ou LEDs, do inglês Light Emmiting Diodes) em sistemas de iluminação pública, cobrindo lacunas existentes no cenário nacional, este trabalho traz uma ampla análise sobre este tema. São apresentados conceitos básicos da fotometria clássica e um estudo sobre adaptações da fotometria para baixos níveis de luminância, que é a condição observada nas vias públicas durante o período noturno. Propõe-se a utilização de métricas escotópicas em sistemas de iluminação pública, uma vez que estas melhor representam a real sensação visual (se comparadas às métricas clássicas – fotópicas) nas condições de iluminamento típicas observadas nestes sistemas. Aspectos gerais da iluminação pública e um histórico da evolução do sistema nacional são brevemente apresentados bem como uma discussão sobre a situação atual deste sistema e das tecnologias utilizadas. O trabalho traz também um estudo sobre características ópticas, elétricas e mecânicas dos LEDs e uma análise dos diferentes tipos de LEDs brancos mais utilizados (HB – High Brightness – e HP – High Power – LEDs). Algumas normas e recomendações aplicáveis à utilização de LEDs em iluminação pública são analisadas e discutidas, com o intuito de se investigar lacunas ainda não cobertas pela normatização existente. Análises de resultados de ensaios de laboratório e de campo, inéditos no país, realizados com alguns modelos de luminárias LED para iluminação pública disponíveis no mercado, são também apresentadas. Um estudo sobre acionamento de LEDs é realizado, abordando técnicas de equalização de corrente entre arranjos série de LEDs associados em paralelo e diferentes tipos de circuitos de acionamento para LEDs. São propostas, analisadas e implementadas uma estrutura inédita de baixo custo para a equalização de corrente e um circuito para o acionamento de LEDs baseado na integração de dois conversores cc cc não isolados. A topologia de dois estágios proposta é composta por um conversor boost no primeiro estágio, utilizado para a correção do fator de potência e por um conversor buck no segundo estágio, utilizado para o controle da corrente nos LEDs. Por fim, o acompanhamento da implantação e do desempenho, ao longo de dez meses, do projeto piloto de iluminação pública empregando LEDs instalado no anel viário da Faculdade de Engenharia da UFJF é apresentado.
In order to present contributions to the use of light emitting diodes (LEDs) in public lighting systems, covering gaps on the national scenario, this work encompasses abroad analysis related to this issue. Basic concepts of classical photometry are presented and so a study of photometry’s adaptations for low luminance levels. It is proposed the use of scotopic metrics for street lighting systems, since they can better represent the actual visual sensation (when compared to the classical one – photopic metrics) on its typical nighty conditions. General aspects of street lighting and the history of the national’s public lighting system are briefly presented as well as a discussion about the current situation of the Brazilian system and technologies adopted. The work also brings a study of mechanical, electrical and optical characteristics of LEDs and an analysis of the two different types of commonly used white LEDs (HB – High Brightness – and HP – High Power - LEDs). Some standards and recommendations related to the use of LEDs in street lighting are analyzed and criticized, with the aim of show some gaps not yet covered by the existent standards. An unprecedented analysis regarding laboratory and field test benchmarking, taken for some luminaires available in commerce, is also presented. A study of LED driving is presented, covering equalization techniques for parallel LEDs strings and different types of LED driving circuits. It was proposed, analyzed and implemented a novel and low cost structure for current equalization and an LED driver, based on the integration of two non-isolated dc dc converters. This proposed two stages topology is composed by a boost converter, on the first stage, employed to the power factor correction and a buck converter, on the second stage, to control the LED’s current. Finally, the process of monitoring the installation and the performance, during ten months, of the LEDs public lighting pilot project, on the roadway belt of Engineering Faculty of UFJF is presented.

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Rocha, Regina Célia. "Visita de animal de estimação: proposta de atividade terapêutica assistida por animais a pacientes internados em hospital oncológico." Pontifícia Universidade Católica de São Paulo, 2015. https://tede2.pucsp.br/handle/handle/15454.

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The pets visit has been coming in this institution since 2011 and professionals in Health Psychology Team with specialization in ATAA coordinate it. The animal is part into the psychological treatment of patients, such as care and comfort references, basic conditions to cope with cancer. The animal may be a reference to improve the quality of life during treatment and hospitalization, reflecting the strong bond that exists in the relationship, in care measures. Have the opportunity to see the pet, even if for the last time brings a sense, providing opportunities on reframing illness and life - through mendering and renewing therapeutic effects. This study aimed to observe the effects of ATAA, here characterized as 'Pets for Business Programme', in a group of three patients with oncological diseases, admitted to ICESP - Institute of São Paulo State Cancer - Frias Octavius Oliveira, comparing them to the literature on the ATAA. According to literature (Brickell, 1984; Struckus, 1989; Wall, 1994; McVarisch, 1995; Panzer-Koplow, 2000; Sorrell, 2006; Souter & Miller, 2007), the effectiveness of Animals Visit Program ICESP improves and balances the psychological state of cancer patients and their families, enhancing their coping resources on life quality improvement both patients and their families, increasing resilience which minimizes psychologic and behavioral symptoms that interfere into treatment and hospitalization, reducing stress, pain and isolation inherent in the process (DIEFENBECK, BOUFFAR, MATUKAITIS, HASTINGS, and COBLE, 2010; HOROWITZ, 2010). Thus, the Animals Visit Program to ICESP confirms the theory there is a great need to re-humanize health practices, developing and providing up humanistic resources for care. It is not just an ethical issue but also rather an urgent need in healthcare paradigm
A Visita de Animal de Estimação acontece nessa instituição desde 2011, sendo coordenada pelos profissionais da Equipe de Psicologia Hospitalar com Especialização em ATAA. Nessa atividade, o animal é parte integrante do tratamento psicológico do paciente, como referência de cuidado e conforto, condições primordiais para o enfrentamento do câncer. O animal pode ser a referência para melhorar a qualidade de vida durante o tratamento e a hospitalização, traduzindo o forte vínculo existente nessa relação em medidas de cuidado. Ter a oportunidade de ver seu animal de estimação mesmo que pela última vez traz um sentido, oportunizando a ressignificação do adoecer e da vida com efeitos terapêuticos reparadores e renovadores. Este trabalho teve como objetivo observar os efeitos da ATAA, aqui caracterizada como Programa de Visita de Animais de Estimação , em um grupo de três pacientes com doenças oncológicas, internados no ICESP Instituto do Câncer do Estado de São Paulo Otávio Frias de Oliveira, comparando-os com a literatura sobre a ATAA. Em concordância com a literatura (Brickel, 1984; Struckus,1989; Wall, 1994; McVarisch,1995; Panzer-Koplow, 2000; Sorrell, 2006; Souter & Miller, 2007), constatamos a eficácia do Programa Visita de Animais de Estimação do ICESP na melhora e equilíbrio do estado psicológico de pacientes oncológicos e familiares, realçando seus recursos de enfrentamento, melhora da qualidade de vida de seus pacientes e familiares, incremento de resiliência, a minimização de manifestações psíquicas e comportamentais que interferem no tratamento e hospitalização, redução do estresse, da dor e isolamento inerentes ao processo (DIEFENBECK, BOUFFAR, MATUKAITIS, HASTINGS, E COBLE, 2010; HOROWITZ, 2010). Dessa forma, o Programa Visita de Animais de Estimação ao ICESP vem comprovar a teoria que, sem dúvida, há uma grande necessidade de se re-humanizar as práticas em saúde, desenvolvendo-se e fornecendo-se recursos humanísticos para o cuidado. E isso não apenas por uma questão ética mas sim pela urgente necessidade na área de saúde de passar do paradigma da conquista ao paradigma do cuidado

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Wang, Huijie. "Detection of Humans in Video Streams Using Convolutional Neural Networks." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214436.

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This thesis is focused on human detection in video streams using Convolutional Neural Networks (CNNs). In recent years, CNNs have become common methods in various computer vision problems, and image detection is one popular application. The performance of CNNs on the detection problem has undergone a rapid increase in both accuracy and speed. In this thesis, we focus on a specific sub-domain of detection: human detection. Furthermore, it makes the problem more challenging as the data extracted from video streams captured by a head-mounted camera and therefore include difficult view points and strong motion blur. Considering both accuracy and speed, we choose two models with typical structures--You Only Look Once (YOLO) and Single Shot MultiBox Detector (SSD)--to experiment how robust the models perform on human domain with motion blur, and how the differences between the structures may influence the results. Several experiments are carried out in this thesis. With a better design of structure, SSD outperforms YOLO in various aspects. It is further proved as we fine-tuned YOLO and SSD300 on human data in Pascal VOC 2012 trainval dataset, showing the efficiency of SSD with fewer classes trained. As for motion blur problem, it is shown in the experiments that SSD300 has good ability to learn blurred patterns. The structure of SSD300 is further tested with regard to the design of default boxes and its performance on different scales and locations. The results show that the SSD model has a superior performance on online detection in video streams, but with a more customized structure it has potential to achieve even better results.
Detta examensarbete undersöker problemet att detektera människor i videströmmar med hjälp av convolutional neural networks (CNNs). Under de senaste åren har CNNs ökat i användning, vilket medfört stora förbättringar i noggrannhet och beräkningshastighet. CNN är nu en populär metod i olika datorseende- och bildigenkänningsproblem. I detta projekt fokuserar vi på en specifik subdomän: detektion av människor. Problemet försvåras ytterligare av att vår videodata är inspelad från en huvudmonterad kamera. Detta medför att vårt system behöver hantera ovanliga betraktningsvinklar och rörelseoskärpa. Efter att ha tagit hänsyn till beräkningshastighet och detektionskvalitet har vi valt att undersöka två olika CNN-modeller: You Only Look Once (YOLO) och Single Shot MultiBox Detector (SSD). Experimenten har designats för att visa hur robusta metoderna är på att detektera människor i bilder med rörelseoskärpa. Vi har också undersökt hur modifikationer på nätverksstrukturer kan påverka slutresultaten. Flera experiment har gjorts i detta projekt. Vi visar att SSD ger bättre resultat än YOLO i många avseenden, vilket beror på att SSD har en bättre designad nätverksstruktur. Genom att utföra fin-anpassning av YOLO och SSD på bildkollektionen i Pascal VOC 2012 kan vi visa att SSD fungerar bra även när vi tränar på färre objektklasser. SSD300 har också god förmåga att lära mönster som påverkats av oskärpa. Vi analyserar även hur valet av position och skalor av de predefinierade sökområdenen påverkar resultaten från SSD300. Resultaten visar att SSD-modellen presterar överlägset i realtidsdetektion i videoströmmar. Genom att anpassa strukturerna ytterligare finns potential att uppnå ännu bättre resultat.

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Sych, Alexey, and Олексій Сергійович Сич. "Image depth evaluation system by stream video." Thesis, National Aviation University, 2021. https://er.nau.edu.ua/handle/NAU/50762.

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1. Depth map generation for 2d-to-3d conversion by short-term motion assisted color segmentation/Yu-Lin Chang, Chih-Ying Fang, Li-Fu Ding, Shao-Yi Chen, and Liang-Gee Chen - DSP/IC Design Lab, Graduate Institute of Electronics Engineering, National Taiwan University, Taipei, Taiwan 2. Scharstein D., Szeliski R. A taxonomy and evaluation of dense two-frame stereo correspondence algorithms // Int. Journal of Computer Vision 47. April-June 2002. PP. 7–42. 3. Разработка и исследование алгоритма вычисления карты глубины стереоизображения/ В.В. Воронин. 4. Метод оценки глубины сцены и текстуры невидимых частей изображения URL: https://neurohive.io/ru/papers/pokazat-to-chto-skryto-metod-ocenki-glubiny-i-nevidimyh-chastej-izobrazhenij/ (Last accessed: 11.01.2021).
One of the data processing applications is stereo vision, in which obtaining a three-dimensional scene is based on models for determining the depths of key points of images from a video sequence or several images. If it is considered an example with a person, then a two-dimensional image is formed on the retina, but despite this, a person perceives the depth of space, that is, has three-dimensional, stereoscopic vision. As a result, in the presence of data on the size of an object, it can be estimated the distance to it or understand which of the objects is closer. When one object is in front of the other and partially obscures it, the person perceives the front object at a closer distance. Because of this, the need arose to teach machine devices to do this for various tasks. Based on the processing results, you can have spatial information for assessing the relief, obstacles while driving, etc. This algorithm is based on combining images of the same object, photographed or filmed on video with constant camera parameters and in the same focal plane from different angles, allows to obtain information about the distance to the object by perspective distortions (discrepancies).
Одним із додатків для обробки даних є стереобачення, в якому отримання тривимірної сцени базується на моделях для визначення глибини ключових точок зображень із відеопослідовності або декількох зображень. Якщо це розглядати як приклад з людиною, то на сітківці утворюється двовимірне зображення, але, незважаючи на це, людина сприймає глибину простору, тобто має тривимірне, стереоскопічне бачення. Як результат, за наявності даних про розмір об’єкта можна оцінити відстань до нього або зрозуміти, який з об’єктів знаходиться ближче. Коли один предмет перебуває перед іншим і частково затемнює його, людина сприймає передній предмет на більш близькій відстані. Через це виникла потреба навчити машинні пристрої робити це для різних завдань. На основі результатів обробки ви можете мати просторову інформацію для оцінки рельєфу, перешкод під час руху тощо. Цей алгоритм заснований на поєднанні зображень одного і того ж об'єкта, сфотографованих чи знятих на відео з постійними параметрами камери і в одній і тій же фокальній площині з різних кутів, дозволяє отримувати інформацію про відстань до об'єкта шляхом перспективних спотворень (розбіжностей).

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Bankarusamy, Sudhangathan. "Towards hardware accelerated rectification of high speed stereo image streams." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-37522.

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The process of combining two views of a scene in order to obtain depth information is called stereo vision. When the same is done using a computer it is then called computer stereo vision. Stereo vision is used in robotic application where depth of an object plays a role. Two cameras mounted on a rig is called a stereo camera system. Such a system is able to capture two views and enable robotic application to use the depth information to complete tasks. Anomalies are bound to occur in such a stereo rig, when both the cameras are not parallel to each other. Mounting of the cameras on a rig accurately has physical alignment limitations. Images taken from such a rig has inaccurate depth information and has to be rectified. Therefore rectification is a pre-requisite to computer stereo vision. One such a stereo rig used in this thesis is the GIMME2 stereo camera system. The system has two 10 mega-pixel cameras with on-board FPGA, RAM, processor running Linux operating system, multiple Ethernet ports and an SD card feature amongst others. Stereo rectification on memory constrained hardware is a challenging task as the process itself requires both the images to be stored in the memory. The FPGA on the GIMME2 systems must be used in order to achieve the best possible speed. Programming a system that does not have a display and for used for a specific purpose is called embedded programming. The purpose of this system is distance estimation and working with such a system falls in the Embedded Systems program. This thesis presents a method that makes rectification a step ahead for this particular system. The functionality of the algorithm is shown in MATLAB and using VHDL and is compared to available tools and systems.

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Foucher, Philippe. "Etude d'indicateurs morphologiques pour la caractérisation de l'état hybride de végétaux par analyse d'images." Angers, 2003. http://www.theses.fr/2003ANGE0015.

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L'objectif de ce travail est d'étudier comment la vision artificielle peut être utilisée, selon des méthodes d'analyse de forme, comme un indicateur du changement d'état du végétal. Dans ce but, des indicateurs morphologiques permettant d'émettre un diagnostic sur l'état de la plante lorsque celle-ci est soumise à des déficits hydriques plus ou moins prononcés, sont recherchés. L'étude est réalisée sur des images de forsythias acquises en visée verticale. La procédure mise en œuvre pour la vision artificielle se décompose en deux étapes. La première consiste à mettre au point une méthode permettant de classifier les pixels de l'image en deux groupes : végétal et fond. A cet effet, un perceptron à une couche cachée est testé avec succès. La deuxième étape concerne l'identification des paramètres traduisant l'évolution morphologique globale du végétal au cours du stress hydrique. Plusieurs méthodes ont été développées et testées. Pour trois d'entre elles, un seuil au-delà duquel le végétal peut-être considéré comme stressé, a pu être défini de façon absolue. Une étude physiologique de l'état hydrique du végétal est menée en parallèle de façon à valider les résultats obtenus par vision artificielle
The purpose of this work is to study how artificial vision, using shape analysis methods, can indicate a modificatifion of the state of the plant. To this end, morphological indicators, allowing a diagnosis in the case of plants when water deficits are fairly high, are researched. The study is realised on images of forsythias looked at from a horizontal plane. The artificial vision is composed of two steps. The first one consists of developing a method to classify pixels of the image in two groups : the plant and its background. Thus, a one hidden layer perceptron was tested with success. The second step concerns the identification of parameters indicating the whole morphological evolution of plants under water stress conditions. Several methods were developped and tested. Three methods allowed to define, in an absolute manner, a threshold above which the plant can be considered stressed. A physiological study of the water status of the plant was undertaken in a parallel way to validate the results obtained-by artificial vision

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Pesochinsky, Nina. "Effect of refractive vision correction of myopia and hyperopia through laser surgery (LASIK & PRK) on symptoms of depression, stress perception and self-esteem in adults (22-55)." Thesis, Capella University, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10288076.

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The purpose of this study was to assess the effects of refractive vision correction through laser surgery (LASIK & PRK) of adults of working age (22-55). This study examined and compared the symptoms of depression, stress perception, and self-esteem prior to surgery and one month after surgery, when sufficient healing has occurred. Research has shown that vision impairment has been reported to be one of the 10 most significant causes of disability in the United States, and, even though clinicians are encouraged to assess emotional response to vision loss, the psychological factors that that play a role in adjustment to vision loss have not been sufficiently studied.

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Forysewicz, Monika. "Analysis of the deformation and stress condition in the visco-elastic-plastic materials processing area during a high-speed single-blade cutting : PhD thesis summary : [synopsis]." Rozprawa doktorska, [s.n.], 2015. http://dlibra.tu.koszalin.pl/Content/1058.

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McKeon, Sean Patrick. "A GPU Stream Computing Approach to Terrain Database Integrity Monitoring." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/cs_theses/65.

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Synthetic Vision Systems (SVS) provide an aircraft pilot with a virtual 3-D image of surrounding terrain which is generated from a digital elevation model stored in an onboard database. SVS improves the pilot's situational awareness at night and in inclement weather, thus reducing the chance of accidents such as controlled flight into terrain. A terrain database integrity monitor is needed to verify the accuracy of the displayed image due to potential database and navigational system errors. Previous research has used existing aircraft sensors to compare the real terrain position with the predicted position. We propose an improvement to one of these models by leveraging the stream computing capabilities of commercial graphics hardware. "Brook for GPUs," a system for implementing stream computing applications on programmable graphics processors, is used to execute a streaming ray-casting algorithm that correctly simulates the beam characteristics of a radar altimeter during all phases of flight.

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Vu, Manh Huyen. "Effet des contraintes et de la température sur l'intégrité des ciments des puits pétroliers." Phd thesis, Université Paris-Est, 2012. http://pastel.archives-ouvertes.fr/pastel-00861315.

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Durant la phase de construction des puits pétrolier, le ciment est coulé dans l'espace annulaire entre le cuvelage et la roche environnante. La gaine de ciment a pour but de tenir le cuvelage, garantir l'étanchéité des puits pétroliers, ou des réservoirs de stockage de CO2, et de protéger le cuvelage de la corrosion. Au cours de la vie du puits, cette gaine de ciment est soumise tout le long du puits à des sollicitations thermiques et mécaniques qui varient au cours du temps et qui peuvent modifier ses propriétés et altérer son étanchéité. L'objet de cette thèse est d'étudier l'effet de la température et des contraintes sur les propriétés mécaniques de la pâte de ciment en cours de prise et de la pâte de ciment durcie. L'approche est basée sur une étude expérimentale qui combine des essais calorimétriques, des mesures de vitesse des ondes et des essais oedométriques avec le système des cellules STCA (Slurry To Cement Analyzer) sur le ciment en cours de prise ainsi que des essais de compression uniaxiale et triaxiale sur la pâte de ciment durcie. Les résultats expérimentaux ont montré que la température et la pression accélèrent la cinétique d'hydratation et que la température affecte significativement les propriétés élastiques du matériau tandis que la pression ne les influence pas pour une gamme de pression limitée à 20MPa. Une modélisation de la cinétique d'hydratation associée à une technique d'homogénéisation est proposée afin d'interpréter les essais. On a mis aussi en évidence que lorsque la prise se fait sous contraintes mécaniques, des déformations irréversibles peuvent se développer dans la pâte de ciment, ce qui peut conduire à la formation d'un micro-annulaire entre la gaine ciment, le cuvelage et la formation géologique. Le comportement différé de la pâte de ciment durcie a été étudié à partir d'essais de fluage uniaxiaux et d'essais de compression isotrope. Les essais ont mis en évidence que le fluage sous chargement uniaxial est plus important pour un ciment hydraté à une température plus élevée, ce qui est attribué à une microstructure plus hétérogène. Un modèle visco-endommageable permettant de reproduire les phases de fluage primaire et tertiaire a été développé. Les essais de compression isotrope drainés et non-drainé isothermes sous forte contrainte ont montré un comportement différé avec hystérésis lors de cycles décharge-recharge. Ces essais ont été analysés à partir d'un modèle de comportement poro-visco-plastique. Le comportement élastoplastique à court terme a été abordé à l'aide des essais triaxiaux sous chargement déviatorique drainé. Ces essais ont mis en évidence que la température d'essai affecte fortement la surface de charge initiale et les déformations tandis qu'elle ne modifie pas significativement la surface de rupture. Un modèle de plasticité avec une surface de charge fermée et un écrouissage dépendant des déformations plastiques accumulées a été développé pour décrire ces essais. Enfin, une étude préliminaire sur les effets des cycles mécaniques et thermiques a été menée. Des cycles thermiques ne dépassant pas la température d'hydratation ne semblent pas affecter les propriétés mécaniques du matériau. Cependant, une dégradation très rapide avec le nombre de cycles mécaniques a été mise en évidence lorsque la contrainte dépasse 60% de la résistance en compression simple

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Rodrigues, Valéria Cristina. "Distribuição espacial e bem-estar de aves poedeiras em condições de estresse e conforto térmico utilizando Visão Computacional e Inteligência Artificial." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/11/11131/tde-13032007-161048/.

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As pesquisas sobre comportamento animal possuem como objetivo identificar e quantificar sinais de sofrimento a fim de eliminar os problemas obedecendo às normas de bem-estar. As alterações destes comportamentos mostram as necessidades ambientais para sua sobrevivência. Em certos casos, apenas as mudanças comportamentais podem evidenciar uma situação de estresse. Quando há mudanças na temperatura do ambiente, os animais apresentam várias respostas para manter a temperatura do corpo, começando com a conservação máxima de energia como a inatividade. Duas das mais efetivas características do comportamento termorregulatório incluem seleção de ambiente e ajuste de postura. Técnicas de processamento e análise de imagens podem vir a colaborar com a busca de informações contidas em imagens de animais confinados. Métodos invasivos de quantificação de comportamento mostram que há interferência do experimentador nas reações dos animais, comprometendo os resultados da pesquisa. Este trabalho visou obter, através da Visão Computacional, informações quanto à distribuição espacial de aves poedeiras frente a situações de conforto e estresse térmicos. Foram analisadas seqüências de imagens em ambiente MATLAB 7.0 ® de dois grupos de 5 aves (Hy-line W36) com 21 semanas de idade em condições de conforto térmico (T= 26°C ± 2°C e UR= 60% ± 2%) e 5 aves em condições de estresse térmico (T= 35°C ± 2°C e UR= 70% ± 2%) controladas em câmara climática. As aves foram demarcadas com tintas não tóxicas na região dorsal. Através de técnicas de clusterização de cores e localização do centro geométrico das aves, foi possível analisar a freqüência destas nas regiões de ninho, comedouro, bebedouro, área livre e \"bebedouro + comedouro\", e através do uso de redes Neurais Artificiais, foi possível obter padrões de formas do corpo das aves e relacioná-los a alguns comportamentos. A distribuição espacial é um forte indício das necessidades do animal em diferentes condições evidenciando que a freqüência em algumas regiões pode ser um indicativo de desconforto. A técnica de processamento e análise de imagens mostra-se como um método confiável e livre de subjetividade ou influência da fadiga humana no auxilio da classificação da dinâmica dos animais confinados. Trata-se de uma forma eficiente de analisar imagens de forma rápida para se ter conhecimento da dinâmica dos animais confinados ao longo do tempo. A necessidade do animal é demonstrada através de freqüências em determinadas regiões de interesse para seu bem-estar.
The animal behavior researches have as objective identify and quantify suffering signals in order to eliminate the problems obeying the welfare norms. The alterations of these behaviors show the ambient necessities for the animals\' survivals. In certain cases, only the abnormal behaviors can evidence a situation of stress. When the environment temperature changes, the animals present some answers to keep the body\'s temperature constant, starting with the maximum conservation of energy as the inactivity. Two of the most effective characteristics of the thermoregulatory behavior includes environment selection and position adjustment. Image processing and analysis techniques can collaborate with the research of information contained in images of confined animals. Invasive methods of quantification of the behavior show that there is interference of the experimenter on the animal reactions compromising the research results. This work aimed to know, through the Computer Vision, information about the laying hens\' spatial distribution at the thermal comfort and stress situations. Image sequences of two groups of 5 birds (hy-line W36) aging 21 weeks in conditions of thermal comfort (T= 26°C ± 2°C and UR= 60% ± 2%) and 5 birds in conditions had been analyzed of stress thermal (T= 35°C ± 2°C and UR= 70% ± 2%) and controlled in climatic chamber. The birds had been demarcated with not toxic inks in the dorsal region. Through colors clusters techniques in MATLAB 7.0 ® and the localization of the geometric center of the birds, it was possible to analyze the frequency of these birds in the nest regions, feed through, water through, free area and \"water through + feed through\", and through of Artificial Neural Network was possible to have standards shapes of bodies birds and to refers to some behaviors. The spatial distribution is an important indicative fort of the animal necessities in different conditions evidencing that the frequency in some regions can be a discomfort indicative. The processing technique and analysis of the images reveals as a trustworthy method and free of subjectivity or of the fatigue human`s influence in support of the dynamics classification of the confined animals. It is about one of the efficient form to analyze the images to have a better understanding of the dynamics of the confined animals` dynamics throughout time. The necessity of the animal is demonstrated through frequencies in determined regions of interest for its welfare condition.

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41

Godard, Rebecca. "La prévention des symptômes d'intrusions traumatiques : une approche cognitive." Thesis, Université de Lorraine, 2013. http://www.theses.fr/2013LORR0341/document.

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Le jeu de « Tetris » peut-il vraiment diminuer la survenue des intrusions traumatiques ? C’est ce qu’indique une étude récente de Holmes et al. (2009). Les intrusions traumatiques représentent un des trois symptômes majeurs de l’état de stress post traumatique. Lors de l’exposition à un évènement traumatique, le traitement de l’information ne s’effectue pas de la même manière que dans une situation quotidienne. Les informations sont principalement traitées dans leurs composantes perceptives et sensorielles et manquent à la fois de conceptualisation et de contextualisation. Ce déséquilibre empêche l’intégration de la représentation de l’événement traumatique au sein de la mémoire autobiographique. Riches en détails sensori-perceptifs, les intrusions traumatiques contribuent à la survenue des manifestations d’hyperactivation neurovégétatives et induisent une détresse émotionnelle et psychique importante lors de leur réactivation en mémoire. Les connaissances actuelles des sciences cognitives nous permettent une meilleure compréhension des processus à l’œuvre lors de la formation des intrusions. Au travers de cette recherche, nous proposons d’approfondir la compréhension de la genèse des intrusions traumatiques. Nous souhaitons poursuivre les travaux publiés par l’équipe de recherche du Professeur Emily Holmes indiquant que la réalisation d’une tâche visuo-spatiale permettrait de diminuer la survenue des intrusions traumatiques
Can Tetris game really reduce analogue traumatic intrusions? A recent research conducted by Holmes et al. (2009) show this conclusion. Traumatic intrusions are one of three main symptom of post-traumatic stress disorder. During exposition to a traumatic event, information processing is not the same that usually. Under extreme stress, perceptual information is mainly processed leading to a lack of conceptual framework. This maladjustment prevent the build of integrate representation to autobiographical memory. Full of sensorial and perceptive details, traumatic intrusions lead to neurovegetative hyperarousal, emotional and psychological distress when reactivated. Current know to cognitive sciences we allow better understanding to processing at work in build of traumatic intrusions. We want to continue the research of Holmes et al. indicating that the realization of visuospatial task reduces traumatic intrusions

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42

Bouvet, Geoffrey. "Relations entre microstructure et propriétés physico-chimiques et mécaniques de revêtements époxy modèles." Thesis, La Rochelle, 2014. http://www.theses.fr/2014LAROS039/document.

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Ce travail de thèse porte sur l’étude et la mise en évidence de relations microstructure-propriétés dans des revêtements modèles à base époxy représentatifs de peinture anticorrosion. Ces relations sont établies aussi bien à l’état initial que lors de vieillissements hygrothermiques. Cette étude a tout d’abord consisté à caractériser les propriétés physico-chimiques et mécaniques du système stœchiométrique DGEBA/DAMP totalement réticulé. Ces propriétés ont été comparées à celles du système DGEBA/TETA et ont permis de montrer la forte influence de la microstructure sur ces propriétés initiales. Des vieillissements hygrothermiques cycliques à différentes températures sur films libres ont été effectués pour mesurer l’impact de la microstructure sur la durabilité des systèmes époxy. Ces travaux ont pu montrer l’influence des interactions eau-polymère dans les phénomènes de diffusion. De plus, les évolutions de certaines propriétés physico-chimiques et mécaniques ont pu être caractérisées à l’aide de la DMA (mors submersibles), lors des différentes étapes de sorption-désorption. Un comportement pseudo-fickien a pu être mis en évidence lors de la première sorption, suivi d’un comportement fickien lors des autres étapes. Les causes inhérentes à cette évolution ont pu être avancées, en mettant en jeu des réorganisations microstructurales des systèmes époxy étudiés. D’autres vieillissements hygrothermiques ont été réalisés à l’aide de la SIE sur des revêtements pour étudier l’effet de l’interface revêtement/substrat acier sur les phénomènes de diffusion, notamment le rôle des contraintes résiduelles. L’influence de la contrainte visco-élastique sur les phénomènes de prise en eau des revêtements a finalement été étudiée
This work highlights the microstructure-properties relations inside representative epoxy based model coatings for anticorrosion paints. These relations have been established for the initial state as well as the hygrothermal ageing. First, we characterised physico-chemical and mechanical properties of the totally crosslinked DGEBA/DAMP stoichiometric system. These properties have been compared to the DGEBA/TETA system and they showed the strong influence of the microstructure on these initial properties. Cyclic hygrothermal ageing have been completed at different temperatures on free films, in order to measure the impact of the microstructure on the durability of epoxy systems. This work has shown the influence of the water-polymer interactions on diffusion phenomena. Moreover, the evolutions of several physico-chemical and mechanical properties have been characterised using DMA (submersible clamps), during different sorption-desorption steps. A pseudo-fickian behaviour has been evidenced during the first sorption, and it was followed by a fickian behaviour for all other steps. The inherent causes of this evolution have been proposed, by considering microstructural reorganisations of the studied epoxy systems. Other hygrothermal ageing have been carried out using EIS on coatings, in order to study the effects of the coating/steel substrate interface on diffusion phenomena, especially the role of residual stresses. We finally studied the influence of the visco-elastic stress on the coating water intake phenomena

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43

Fernandes, Leandro Henrique Oliveira. "Simulação de fenômenos óticos e fisiológicos do sistema de visão humana." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/55/55134/tde-09052008-161636/.

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O ganho crescen te de desempenho nos computadores modernos tem impulsionado os trabalhos científicos nas áreas de simulação computacional. Muitos autores utilizam em suas pesquisas ferramentas comerciais que limitam seus trabalhos ao esconder os algoritmos internos destas ferramentas e dificultam a adição de dados in-vivo nestes trabalhos. Este trabalho explora esta lacuna deixada por aqueles autores. Elaboramos um arcabouço computacional capaz de reproduzir os fenômenos óticos e fisiológicos do sistema visual. Construímos com superfícies quádricas os modelos esquemáticos do olho humano e propomos um algoritmo de traçado de raio realístico. Então realizamos um estudo nos modelos esquemáticos e a partir deles mais a adição de dados in-vivo obtidos de um topógrafo de córnea extraímos informações óticas destes modelos. Calculamos os coeficientes e Zernike dos modelos para tamanhos diversos de pupila e obtivemos medidas de aberração do olho humano. Os resultados encontrados estão de acordo com os trabalhos relacionados e as simulações com dados in-vivo estão consoantes com as produzidas por um aparelho de frente de onda comerciais. Este trabalho é um esforço em aproveitar as informações adquiridas pelos equipamentos modernos de oftalmologia, além de auxiliar o entendimento de sistemas visuais biológicos acabam também em auxiliar a elaboração de sistemas de visão artificial e os projetistas de sistemas óticos
The increase in performance of the modern computers has driven scientific work in the areas of computer simulation. Many authors use in their research commercial tools that use embedding algorithms, which sources are not provided, and it makes harder and sometimes impossible, the development of novel theories or experiments. This work explores this gap left for those authors. We present a computational framework capable to reproduce the optical and physiological phenomena of the human visual system. We construct schematical models of the human eye from quadrics surfaces and consider an algorithm of realistic ray tracing. Afterward, we performed a study on schematics models and in addition we introduce, in these models, in-vivo data obtained from corneal topography machine and extract optical information. We calculate the Zernike coefficients in the models for different sizes of pupil and measures of aberration of the human eye. The results are in agreement with related work and simulations with in-vivo data are according with the produced by a commercial wave-front device. This work is an effort in using to advantage the information acquired for the modern equipment of ophthalmology, besides assisting the understanding of biological visual systems, it also helps the development of artificial vision systems and the designing of optical systems

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44

Bérard, François. "Vision par ordinateur pour l'interaction homme-machine fortement couplée." Phd thesis, Université Joseph Fourier (Grenoble), 1999. http://tel.archives-ouvertes.fr/tel-00004804.

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Cette thèse traite de l'usage de la vision par ordinateur pour des situations d'interaction fortement couplée (IFC) entre l'Homme et la machine. Une interaction est fortement couplée sur un intervalle de temps donné lorsque les systèmes humain et artificiel sont engagés de manière continue dans l'accomplissement d'actions physiques mutuellement observables et dépendantes sur cet intervalle. Le déplacement d'un objet graphique avec la souris relève de l'IFC. Nous modélisons l'IFC sous la forme d'un système en boucle fermée constitué de deux sous-systèmes de type stimulus-réponse. Ce modèle permet d'identifier des requis applicables à la conception, à la réalisation ou à l'évaluation de dispositifs utilisables en IFC. En particulier, nous recommandons une latence inférieure à 50 ms., une résolution adaptée à la tâche utilisateur et la satisfaction de la stabilité statique. Nous considérons ensuite l'usage de la vision par ordinateur dans ce contexte. Une revue des deux approches dominantes du domaine, vision orientée modèle et vision par apparence, nous permet de justifier notre choix de la seconde dont les techniques, de plus faible complexité de calcul, sont susceptibles de satisfaire le requis de latence. Nous présentons ensuite les techniques de vision par ordinateur que nous avons réalisées en adoptant une approche résolument dirigée par la tâche utilisateur. Les deux derniers chapitres détaillent nos expérimentations à la fois techniques et ergonomiques avec la mise en ¦uvre de deux prototypes : le tableau magique et la fenêtre perceptuelle. Le premier utilise un suivi du doigt en vision par ordinateur pour la désignation d'inscriptions sur un tableau blanc physique amplifié de services électroniques. La fenêtre perceptuelle, quant à elle, utilise un suivi du visage comme nouveau flux d'entrée spatiale dans une interface graphique usuelle. Ce flux est utilisé pour la navigation dans une fenêtre.

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45

Victor, Trent. "Keeping Eye and Mind on the Road." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6241.

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46

Ahmed, Sameer. "Application d'un langage de programmation de type flot de données à la synthèse haut-niveau de système de vision en temps-réel sur matériel reconfigurable." Phd thesis, Université Blaise Pascal - Clermont-Ferrand II, 2013. http://tel.archives-ouvertes.fr/tel-00844399.

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Les circuits reconfigurables de type FPGA (Field Programmable Gate Arrays) peuvent désormais surpasser les processeurs généralistes pour certaines applications offrant un fort degré de parallélisme intrinsèque. Ces circuits sont traditionnellement programmés en utilisant des langages de type HDL (Hardware Description Languages), comme Verilog et VHDL. L'usage de ces langages permet d'exploiter au mieux les performances offertes par ces circuits mais requiert des programmeurs une très bonne connaissance des techniques de conception numérique. Ce pré-requis limite fortement l'utilisation des FPGA par la communauté des concepteurs de logiciel en général. Afin de pallier cette limitation, un certain nombre d'outils de plus haut niveau ont été développés, tant dans le monde industriel qu'académique. Parmi les approches proposées, celles fondées sur une transformation plus ou moins automatique de langages de type C ou équivalent, largement utilisés dans le domaine logiciel, ont été les plus explorées. Malheureusement, ces approches ne permettent pas, en général, d'obtenir des performances comparables à celles issues d'une formulation directe avec un langage de type HDL, en raison, essentiellement, de l'incapacité de ces langages à exprimer le parallélisme intrinsèque des applications. Une solution possible à ce problème passe par un changement du modèle de programmation même. Dans le contexte qui est le notre, le modèle flot de données apparaît comme un bon candidat. Cette thèse explore donc l'adoption d'un modèle de programmation flot de données pour la programmation de circuits de type FPGA. Plus précisément, nous évaluons l'adéquation de CAPH, un langage orienté domaine (Domain Specific Language) à la description et à l'implantation sur FPGA d'application opérant à la volée des capteurs (stream processing applications). L'expressivité du langage et l'efficacité du code généré sont évaluées expérimentalement en utilisant un large spectre d'applications, allant du traitement d'images bas niveau (filtrage, convolution) à des applications de complexité réaliste telles que la détection de mouvement, l'étiquetage en composantes connexes ou l'encodage JPEG.

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47

Casagrande, Cristiano Gomes. "Desafios da iluminação pública no Brasil e nova técnica de projetos luminotécnicos fundamentada na fotometria mesópica." Universidade Federal de Juiz de Fora (UFJF), 2016. https://repositorio.ufjf.br/jspui/handle/ufjf/2573.

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Os sistemas de iluminação pública (IP) no Brasil atravessam um momento de mudanças significativas, que implicam em novos paradigmas, desafios e perspectivas para o setor. Essas transformações começam com a transferência dos ativos de IP para os municípios, exigindo que os gestores municipais estejam preparados e capacitados para assumir esse serviço público essencial que anteriormente não era de sua responsabilidade. Além disso, novas tecnologias de iluminação, como os diodos emissores de luz (LEDs), surgem como alternativa às tecnologias convencionais, acarretando muitos impactos e alterações de conceitos no projeto, gestão e manutenção dos sistemas de IP. Assim, esta tese traça um panorama da iluminação pública no país, abrangendo questões referentes à gestão e manutenção do sistema, enfatizando os desafios ligados à transferência dos ativos de iluminação pública para os municípios, além da complexidade inerente à mudança de tecnologia para os LEDs. A discussão é organizada em duas vertentes principais: a gestão da IP, com ênfase nos desafios associados à transferência dos ativos; e a consolidação de novas tecnologias, sobretudo os LEDs. Nesse âmbito, com o objetivo de contribuir para uma utilização mais eficiente dos sistemas de iluminação, este trabalho propõe a consolidação da fotometria mesópica na elaboração de projetos luminotécnicos de IP, uma vez que, nesses casos, é comum deparar-se com condições de baixa luminância, nas quais a sensibilidade espectral da visão humana é diferente das condições supostas pela fotometria clássica. Neste sentido, procura-se explorar em detalhes a recomendação CIE 191:2010, que propõe multiplicadores de correção para a adaptação de grandezas fotométricas convencionais em grandezas mesópicas. Todavia, para se obter tais multiplicadores, é necessária a obtenção da relação entre os fluxos escotópico e fotópico da fonte luminosa (relação S/P), o que exige equipamentos especiais não facilmente disponíveis à maior parte dos projetistas. Com o objetivo de contornar essa dificuldade, esta tese de doutorado propõe uma equação geral que permita realizar o cálculo de S/P em função da temperatura de cor correlata e do índice de reprodução de cor da fonte de luz a ser empregada, que são informações normalmente disponibilizadas nos catálogos de fabricantes ou embalagens de lâmpadas comerciais. A equação encontrada apresentou coeficientes de correlação e de determinação próximos da unidade, o que lhe garante boa confiabilidade. Pela obtenção da relação S/P com auxílio da técnica proposta, um projeto luminotécnico típico tem sua rotina alterada, algo que é demonstrado e exemplificado ao final do texto.
The street lighting systems in Brazil are going through a time of significant changes that involve new paradigms, challenges and prospects for the sector. These changes begin with the transfer of street lighting assets to municipalities, demanding that municipal managers are prepared and able to manage this essential public service that previously was not your responsibility. In addition, new lighting technologies such as light-emitting diodes (LED) are an alternative to conventional technologies, resulting in many impacts and changes of concepts in the design, management and maintenance of street lighting systems. Thus, this thesis provides an overview of street lighting in Brazil, covering issues relating to the management and maintenance of the system, emphasizing the challenges linked to the transfer of street lighting assets to the municipalities, in addition to the inherent complexity of LED technology. The discussion is organized into two main areas: the management of system, with emphasis on the challenges associated with the transfer of assets; and the consolidation of new technologies, especially the LED. In this context, in order to contribute to a more efficient use of lighting systems, this thesis proposes the consolidation of mesopic photometry in the development of street lighting projects, since in such cases it is common to encounter poor conditions luminance, in which the spectral sensitivity of human vision is different from the conditions in the classical photometry. In this sense, it is covered in detail the CIE 191:2010 technical report, which proposes correction factors for the adaptation of conventional photometric quantities in mesopic quantities. However, to obtain such factors, it is required to obtain the relationship between the scotopic and photopic luminous flux of light source (S/P ratio), which requires special equipment not readily available to most lighting designers. Thus, this PhD thesis proposes a general equation that provides the S/P ratio as a mathematical function of correlated color temperature and color rendering index of the light source, which are information usually available in catalogs of manufacturers or products packaging. The proposed equation showed correlation coefficient and coefficient of determination parameters closed to unity, which guarantees good reliability. By obtaining the S/P ratio with the aid of proposed technique, a typical lighting design has changed his routine, something that is demonstrated and exemplified in final of the text.

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48

Parolini, Pedro Lucas Leite. "Identificação dos perfis de patrocinadores que agregam mais valor aos eventos de corrida de rua: um estudo na visão dos consumidores do esporte." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/39/39136/tde-13022017-120037/.

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Na década de 90, a corrida de rua sofreu uma alteração significativa no seu conceito de evento. O caráter de entretenimento começou a ser explorado pelos produtores de eventos desse setor, fazendo emergir o conceito de corridas fashions. Só no estado de São Paulo, foram ofertados 415 eventos de corrida de rua, no ano de 2015. Percebendo esse mercado em expansão, empresas de diversos setores procuram se aliar ao esporte em questão e, em contrapartida, as produtoras desses eventos procuram esses patrocinadores para o financiamento das atividades. Com isso, o objetivo desse trabalho foi identificar os perfis de patrocinadores que agregam mais valor aos eventos de corrida de rua: um estudo na visão dos consumidores desse esporte. Para responder esse objetivo, optou-se por uma metodologia qualitativa de caráter exploratório. Foi aplicado um questionário misto à uma amostra de 407 corredores, em quatro eventos de corrida de rua. Esse questionário continha perguntas abertas e fechadas, e as respostas foram analisadas por meio das frequências e seus conteúdos, respectivamente. Como resultado, obteve-se um perfil de patrocinador que seja de segmentos congruentes com o esporte e a corrida de rua, como segmento esportivo, alimentício e de calçados para corredores. Além disso, segundo os consumidores, é importante que os patrocinadores ativem suas marcas durante os eventos da modalidade. Essas ativações devem ser associadas aos atributos que esses consumidores consideram como atributos da corrida de rua, como, saúde, amizade, qualidade de vida, bem-estar, socialização e diversão. Conclui-se que existem patrocinadores que agregam mais valor do que outros, na ótica do consumidor desse esporte. Essas informações podem ser úteis para os produtores de corrida de rua, uma vez que essas empresas que devem ser procuradas em uma possível prospecção de patrocinadores para os eventos da modalidade. Patrocinadores que agregam mais valor ao evento são percebidos pelos consumidores, o que resulta em uma percepção positiva daquele evento em questão e de seus patrocinadores
In the 90s the street race underwent a significant change in your event concept. The entertainment character began to be exploited by the event producers in this sector, giving rise to the concept of fashions races. Only in the state of São Paulo were offered 415 street racing events in 2015. Realizing this expanding market, companies from various sectors are seeking to combine the sport in question, and in turn producing these events seek these sponsors for funding these activities. Thus, objective of this study was to identify the profile of sponsors that add more value to street racing events: a study in view of the consumers of this sport. To meet this objective we chose a qualitative methodology exploratory. A mixed questionnaire to a sample of 407 runners in four road race event was applied. The questionnaire contained open and closed questions, which the frequencies were analyzed the responses and their contents respectively. As a result we got a sponsor profile that is congruent segments with sport and street racing as sports segment, food and shoes for runners. Moreover, according to consumers, these sponsors must activate their brands during the sport events. These activations should be associated with attributes that consumers consider as street racing attributes as health, friendship, quality of life, well-being, socialization and fun. It is concluded that there are sponsors that add more value than others in the consumer\'s view of this sport. This information can be useful for street racing producers, since these companies should be sought in a possible prospect for sponsors for the sport events. Sponsors that add more value to the event are perceived by consumers, resulting in a positive perception of that event in question and its sponsors

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49

Battaini, Michael. "Deformation behaviour and twinning mechanisms of commercially pure titanium alloys." Monash University. Faculty of Engineering. Department of Materials Engineering, 2008. http://arrow.monash.edu.au/hdl/1959.1/61321.

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The deformation behaviour and twinning mechanisms of commercially pure titanium alloys were investigated using complementary diffraction techniques and crystal plasticity modelling. The main motivation for conducting this investigation was to improve understanding of the deformation of titanium to help achieve the long term aim of reducing manufacturing and design costs. The deformation behaviour was characterised with tension, compression and channel die compression tests for three important variables: orientation; temperature from 25 C to 600 C; and composition for two contrasting alloys, CP-G1 and CP-G4. The experimental data used to characterise the behaviour and determine the mechanisms causing it were: textures determined by X-ray diffraction; twin area fractions for individual modes determined using electron back-scatter diffraction; and lattice strains measured by neutron diffraction. A strong effect of the orientation–stress state conditions on the flow curves (flow stress anisotropy) was found. The propensity for prism hai slip was the dominant cause of the behaviour – samples that were more favourably oriented for prism hai slip had lower flow stresses. Twinning was the most significant secondary deformation mode in the CP-G1 alloy but only had a minor effect on flow stress anisotropy in most cases. In the CP-G4 alloy twinning generally did not play a significant role indicating that hc + ai slip modes were significant in this alloy. Differences in the flow stress anisotropy between the two alloys were found to occur largely in the elasto-plastic transition and initial period of hardening. Modelling results indicated that larger relative resolved shear stress values for secondary deformation modes in the higher purity alloy increased the initial anisotropy. Decreasing flow stresses with increasing temperature were largely caused by a decrease in the critical resolved shear stress (CRSS) values for slip, but also by a decrease in the Hall-Petch parameter for slip. The propagation of twinning was found to be orientation dependent through a Schmid law in a similar way to slip – it was activated at a CRSS and hardened so that an increasing resolved shear stress was required for it to continue operating. The CRSS values determined for the individual twin modes were – 65MPa, 180MPa, 83MPa for {1012}, {1122} and {1011} twinning, respectively. Further, twinning was found to be temperature insensitive except when the ability to nucleate twins posed a significant barrier (for {1011} twinning). Also, the CRSS for {1012} twinning was clearly shown to increase with decreasing alloy purity. A thorough method for determining crystal plasticity modelling parameters based on experimental data was formulated. Additionally, twinning was modelled in a physically realistic manner influenced by the present findings using the visco-plastic self-consistent (VPSC) model. In particular: the activity of twinning decreased in a natural way due to greater difficulty in its operation rather than through an enforced saturation; and hardening or softening due to changes in orientation and dynamic Hall-Petch hardening were important. The rigorous modelling procedure gave great confidence in the key experimental findings.

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Mahé, Gwendoline. "La reconnaissance visuelle des mots chez le dyslexique : implication des voies ventrale et dorsale." Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-00919475.

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L'objectif de ces travaux a été d'étudier, à partir des potentiels évoqués, l'implication des voies ventrale (qui sous-tend le traitement expert de l'écrit) et dorsale (qui sous-tend des processus phonologiques et attentionnels) lors de la reconnaissance visuelle des mots chez des adultes dyslexiques. Les spécificités des sujets dyslexiques ont été isolées en les comparant à deux groupes contrôles, appariés sur : l'âge (i.e., des lecteurs experts) et sur le niveau de lecture (i.e., des mauvais lecteurs). Les résultats montrent des déficits du traitement expert de l'écrit, phonologiques et de la détection du conflit spécifiques aux sujets dyslexiques. Nos données montrent aussi des déficits du traitement expert des mots familiers et d'orientation de l'attention communs aux sujets dyslexiques et mauvais lecteurs. Les résultats sont discutés dans le cadre du modèle LCD, de la théorie du mapping phonologique et d'une implication précoce de l'orientation attentionnelle dans la lecture.

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Дисертації з теми "Stress visivo"

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