Age-related macular degeneration (AMD) is the leading cause of blindness inAmerica. The fact that AMD wreaks most of the damage in the center of the retina raises the question of whether light, integrated over long periods, is more concentrated in the macula. A method, based on eye-tracking, was developed to measure the distribution of light in the retina under natural viewing conditions. The hypothesis was that integrated over time, retinal illumination peaked in the macula. Additionally a possible relationship between age and retinal illumination was investigated. The eye tracker superimposed the subject’s gaze position on a video recorded by a scene camera. Five informed subjects were employed in feasibility tests, and 58 naïve subjects participated in 5 phases. In phase 1 the subjects viewed a gray-scale image. In phase 2, they observed a sequence of photographic images. In phase 3 they viewed a video. In phase 4, they worked on a computer; in phase 5, the subjects walked around freely. The informed subjects were instructed to gaze at bright objects in the field of view and then at dark objects. Naïve subjects were allowed to gaze freely for all phases. Using the subject’s gaze coordinates, and the video provided by the scene camera, the cumulative light distribution on the retina was calculated for ~15° around the fovea. As expected for control subjects, cumulative retinal light distributions peaked and dipped in the fovea when they gazed at bright or dark objects respectively. The light distribution maps obtained from the naïve subjects presented a tendency to peak in the macula for phases 1, 2, and 3, a consistent tendency in phase 4 and a variable tendency in phase 5. The feasibility of using an eye-tracker system to measure the distribution of light in the retina was demonstrated, thus helping to understand the role played by light exposure in the etiology of AMD. Results showed that a tendency for light to peak in the macula is a characteristic of some individuals and of certain tasks. In these situations, risk of AMD could be increased. No significant difference was observed based on age.

Sedentary behavior (SB) contributes to many negative health-related outcomes. Motivation to reduce SB and increase physical activity (PA) are necessary to reduce co-morbidities. Tracking SB and PA provides objective data to help promote wellness. The purposes of this quasi-experimental study were to 1) determine the accuracy of three commercially available activity trackers compared to research-grade accelerometers, and 2) explore whether using these activity trackers led to a change in activity level one week after gathering baseline data. Activity trackers used in this study were Apple Watch, Fitbit Surge, and Microsoft Band 2. A convenience sample of college-age students and community members wore the research-grade ActiGraph 3GTX+ accelerometer on the non-dominant wrist for one week. Participants returned and the activity tracker was added to the non-dominant wrist with the ActiGraph 3GTX+ for another week. All activity trackers significantly differed from the ActiGraph accelerometers. Fitbit Surge had a significant regression equation that could adjust for this difference, but not Apple Watch or Microsoft Band 2. Participants had below average sedentary time, exhibiting 288.4 min/day (SD 100.7) of SB. They also surpassed United States PA standards, averaging 130.3 (SD 48.8) min/day of moderate-to-vigorous physical activity. Few significant changes in activity level transpired between week 1 and week 2. In a group that already has low SB and high PA, activity trackers do not seem to make an impact on activity levels. Further testing is required to determine if activity trackers are motivating to reduce SB and increase PA in groups with different activity profiles.

Sedentary time and physical inactivity have negative impacts on health and health costs as well as an impact on workplace wellbeing. There is evidence that people are more sedentary and engage in less physical activity on work days. Additionally, sedentary behavior has been found to increase distress and negative mood. Activity trackers such as Fitbits are a useful way to collect and intervene on sedentary behavior and potentially impact other factors of workplace wellbeing in real time and promote self-monitoring. The reminder to move prompts that are now part of Fitbit models provide an innovative and simple way to intervene on workplace sedentary behavior with hourly movement prompts. This study examined the impact of an intervention on sedentary time at work with Fitbit reminders to move and what impact the intervention had on other factors of workplace wellbeing including depression, positive and negative affect, job stress, and productivity. Participants were university employees who wore a Fitbit device for three weeks and completed pre-and post-study measures. For the first week, the Fitbit displayed only the watch screen with no access to other data. This was done to establish baseline data. For the second week, the Fitbit device and Fitbit app allowed for self-monitoring by displaying the activity being tracked, including steps, distance, calories expenditure, and stairs walked. For the third week, the sedentary time reduction was implemented by activating the Fitbit application reminder to move. This caused the Fitbit to vibrate at the 50-minute mark of the hour if the participant had not moved 250 steps in that time. Results show that having the reminders to move prompt activated decreased sedentary time at work and increased steps throughout the day on work days. These changes in sedentary time significantly contributed to decreases in depression. From the start of the study to after the intervention, on average participants reported significantly less depression, negative affect, and stress and more positive affect, affect balance, social functioning, physical functioning, and productivity at work. The benefits of in the moment self-monitoring and an intervention around sedentary time with Fitbits on factors of workplace wellbeing are discussed as well as limitations, and future directions.

No description available.

This study evaluates the application of an eye tracking device in nursing education. An experiment is designed to test the effectiveness of the eye tracking device used as a tool for providing instructional feedback in error identification and recovery by nursing students undertaking tasks in a simulated clinical setting. This experiment is performed on three groups of nursing students. In the first phase, all groups are tested in a simulated clinical scenario and their eye movements are recorded using an eye tracking device. In the second phase, the evaluation only group (control group) gets instructors’ feedback regarding their performance without referring back to the eye tracker record. The eye tracker only group (experimental group A) is provided with a video of their eye movements which was recorded during their first simulated exercise, but receives no feedback from the instructors. The combined group (experimental group B) is provided with both instructors’ evaluations and their eye movement video. Finally, in the last phase, all the groups are tested once again in the simulated clinical settings. Their performance is observed and compared to determine their relative improvements. Based on these improvements, it will be possible to determine whether an eye tracking device by itself or in combination with evaluation serves as a helpful instructional source during nursing education.

京都大学 / 新制・課程博士 / 博士(理学) / 甲第24406号 / 理博第4905号 / 新制||理||1701(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 中家 剛, 准教授 WENDELL Roger, 教授 永江 知文 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM

Made available in DSpace on 2017-07-24T19:45:51Z (GMT). No. of bitstreams: 1 Edenilson Orkiel.pdf: 13722795 bytes, checksum: 5cf2a7113093b2b5d3ad1e6a916a2e28 (MD5) Previous issue date: 2016-08-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / In this work the intention was to teach the content structuring movements in two dimensions, addressing the concepts related to the uniform motion, accelerated and oblique with the construction and use of simple experiments for it. In this sense, it was built with the student’s rocket powered by water and compressed air, as well as other types of experiments demonstrating the movement of objects making up the record video for later analysis with the help of Tracker computer program. Tracker program is used as a facilitator in the understanding of the concepts related to uniform, accelerated movement as well as movements in two dimensions’ composition or oblique movement. Within these activities, the purpose was to enable students to classes that allow understanding of how to build physical models of motion and the equations that describe them, aiming to make sense of the physical concepts taught. One example is through the Tracker program, enabling students graphing activities of the movements, as well as analysis and interpretation correlating with what has been seen in practice. After analyzing the results, it could be observed that the different classes with the use of ICT, the Tracker program and experiments built by the students themselves, contributed to the motivation and interest in the subject taught at the same time that the road to learning it was easier to reach the success of the proposal. / Neste trabalho a pretensão foi ensinar o conteúdo estruturante movimentos em duas dimensões, abordando os conceitos relacionados aos movimentos uniforme, acelerado e oblíquo com a construção e uso de experimentos simples para isso. Neste sentido, foi construído com os alunos foguetes movidos a água e ar comprimido, bem como outros tipos de experimentos demonstrando o movimento de objetos fazendo-se o registro em vídeo para análise posterior com o auxílio do programa computacional Tracker. O programa Tracker é utilizado como um facilitador no entendimento dos conceitos relacionados aos movimentos uniforme e acelerado, bem como da composição de movimentos em duas dimensões, ou movimento oblíquo. Dentro destas atividades, o propósito foi possibilitar aos alunos aulas que permitam o entendimento de como se constroem os modelos físicos do movimento e as equações que os descrevem, objetivando-se dar sentido aos conceitos físicos ensinados. Como exemplo, citamos, através do programa Tracker, possibilitar aos alunos atividades de construção de gráficos dos movimentos, bem como sua análise e interpretação correlacionando com o que foi visualizado na prática. Após a análise dos resultados obtidos, pôde ser observado que as aulas diferenciadas, com a utilização das TIC, do programa Tracker e de experimentos construídos pelos próprios alunos, contribuíram para a motivação e interesse pelo assunto ensinado ao mesmo tempo que o caminho para a aprendizagem ficou facilitado, atingindo o êxito da proposta.

In this study, a video tracker system for traffic monitoring and analysis is developed. This system is able to detect and track vehicles as they move through the camera&rsquo / s field of view. This provides to perform traffic analysis about the scene, which can be used to optimize traffic flows and identify potential accidents. The scene inspected in this study is assumed stationary to achieve high performance solution to the problem. This assumption provides to detect moving objects more accurately, as well as ability of collecting a-priori information about the scene. A new algorithm is proposed to solve the multi-vehicle tracking problem that can deal with problems such as occlusion, short period object lost or inaccurate object detection. Two different tracking methods are used together in the developed tracking system, namely, the multi-model Kalman tracker and the Markov scene partition tracker. By the combination of these vehicle trackers with the developed occlusion reasoning approach, the continuity of the track is achieved for situations such as target loss and occlusion. The developed system is a system that collects a-priori information about the junction and then used it for scene modeling in order to increase the performance of the tracking system. The proposed system is implemented on real-world image sequences. The simulation results demonstrates that, the proposed multi-vehicle tracking system is capable of tracking a target in a complex environment and able to overcome occlusion and inaccurate detection problems as well as abrupt changes in its trajectory.

Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-09-17T17:22:44Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_impressao.pdf: 2956113 bytes, checksum: e6a4b36626de2a1892da7e9ffd7ac14a (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-09-17T17:22:55Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_impressao.pdf: 2956113 bytes, checksum: e6a4b36626de2a1892da7e9ffd7ac14a (MD5) / Made available in DSpace on 2018-09-17T17:22:55Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Dissertacao_impressao.pdf: 2956113 bytes, checksum: e6a4b36626de2a1892da7e9ffd7ac14a (MD5) Previous issue date: 2018-08-10 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Currently, diverse existing training environments help new users of electric powered wheelchairs (EPW) learn how to drive, acquaint and improve their abilities with these assistive devices. Several authors are developing such environments, and most of them use virtually simulated wheelchairs. Despite the similarities between virtual and real wheelchairs, it is easier to drive the real device because representation of the wheelchair physical behavior is still a problem for virtual simulated environments. Concerning the driving methods, most of them are based on a joystick, which does not give the opportunity for users to test, practice and acquaint themselves with new technologies, such as driving through eye movements. This work implements and tests a more realistic approach for a training environment dedicated to new users of EPW. The proposed system is based on a real EPW controlled by teleoperation, and it is flexible enough to attend to multiple driving methods. An architecture that allows a user to send command messages to control a real EPW through the Internet was implemented to validate the system. The implemented driving methods were conventional joystick, eye-tracker and a generic human-machine interface. For the system’s evaluation, scenarios were created considering the implemented driving methods, and also scenarios considering a long distance teleoperation. The experimental results suggest that new users can practice safely using a real EPW through the Internet, even in a situation with a communication delay of 130.2 ms (average). Furthermore, the proposed system showed potential for attending new EPW users with different types of disabilities and to be a low-cost approach that could be applied in developing countries. / Atualmente, diversos ambientes de treinamento existentes ajudam novos usuários de cadeira de rodas motorizada (CRM) a aprender a comandar, se familiarizar e aprimorar suas habilidades. Vários autores estão desenvolvendo esses ambientes, e a maioria deles está usando CRM virtualmente simulada. Apesar das semelhanças entre a CRM virtual e a real, observouse que é mais fácil comandar o dispositivo real. Isso ocorre porque nesses ambientes virtuais, a representação do comportamento físico da CRM ainda é um problema. Outro aspecto observado, foi a respeito dos métodos de condução, onde a maioria dos trabalhos utiliza apenas o joystick. Porém, esse método não oferece a oportunidade a usuários com deficiência severa de aprender a comandar a partir de novas tecnologias, como por exemplo, o rastreamento ocular. Para superar essas dificuldades, este trabalho propõe, implementa e valida uma abordagem mais realista, a qual é baseada em treinamento por teleoperação e por múltiplos métodos de condução. Foi implementada uma arquitetura que permite ao usuário enviar comandos remotamente para comandar uma CRM real a longas distâncias. Os métodos de condução implementados foram por joystick, eye-tracker e por meio de uma interface humanomáquina genérica. Para a avaliação do sistema, foram criados cenários considerando diferentes configurações. Os resultados experimentais sugerem que novos usuários podem praticar com segurança utilizando uma CRM real através da Internet, mesmo em uma situação com delay de 130,2 ms (média). O sistema proposto mostrou potencial em atender novos usuários de CRM com diferentes tipos de deficiência, bem como de ser uma abordagem de baixo custo com possibilidade de ser aplicada em países em desenvolvimento.

La thèse se place dans le contexte du programme de physique prévu auprès du collisionneur Beijing Electron Positron Collider II, pour lequel l'expérience BESIII (Beijing Electron Spectrometer III) doit subir une jouvence. Mon travail concerne l'amélioration des performances de la trajectométrie centrale de l'expérience, en explorant une nouvelle approche utilisant les capteurs à pixels CMOS (CPS) en remplacement partiel de la chambre à dérive actuelle. Il est validé, qu'un pixel de 39.0X50.8 µm2 permet d'atteindre une résolution spatiale ~10 µm. Cette confirmation ouvre la voie pour le développement d'échelle de grande longueur. Un logiciel générique proposant une stratégie d'optimisation pour un trajectomètre pixellisé a été mis au point et appliqué au cas particulier du BESIII. Il a permis de montrer qu'une configuration à trois couches optimise la résolution sur les trajectoire alors qu'une option incluant une couche double-face atteint une efficacité de reconstruction supérieure. / The thesis addresses the upcoming particle physics program foreseen at the Beijing Electron Positron Collider II, for which the Beijing Electron Spectrometer III (BESIII) is being upgraded. The work presented focused on the upgrade of the central tracker of the experiment by exploring the possibilities offered by a new approach using CMOS Pixel Sensors (CPS) instead of the present gas drift chamber. The performance of CPS with a larger pixel (39.0X50.8 µm2) and a lower power consumption has been validated, which will help to develop long ladders. A general strategy and software to optimise the design of a barrel pixelated tracker has also been developed, and its application on the BESIII silicon tracker indicates that the layout of three evenly placed single-sided layers is favoured by BESIII physics for the best momentum resolution, with an option using one double-sided ladder to achieve a higher tracking efficiency.