Dissertations / Theses: 'Egocentric'

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Surie, Dipak. "Egocentric interaction for ambient intelligence." Doctoral thesis, Umeå universitet, Institutionen för datavetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-50822.

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Ambient intelligence refers to the vision of computationally augmented everyday environments that are sensitive, adaptive and responsive to humans and intelligently support their daily lives. Ambient ecologies are the infrastructures of ambient intelligence. To enable system developers to frame and manage the dynamic and complex interaction of humans with ambient ecologies consisting of a mixture of physical (real) and virtual (digital) objects, novel interaction paradigms are needed. Traditional interaction paradigms like the WIMP (windows, icon, menus, and pointing devices) paradigm for desktop computing operate in a closed world, unaware of the physical, social and cultural context. They restrict human perception and action to screen, mouse and keyboard with the assumption that human attention will be fully devoted to interaction with the computer. Emerging interaction paradigms for ambient intelligence are typically centered on specific devices, specific computing environments or specific human capabilities. Also, many of them are driven by technological advancements rather than viewing the human agent as their starting point. A principled, theoretical approach centered in the individual human agent, their situation and activities that are comprehensive and integrated while at the same time instrumental in the design of ambient ecologies has been lacking. This thesis introduces egocentric interaction as an approach towards the modeling of ambient ecologies with the distinguishing feature of taking the human agent’s body, situation and activities as center of reference, as opposed to the more common device-centric approaches in facilitating human-environment interaction. Egocentric interaction is encapsulated in a number of assumptions and principles such as situatedness, the proximity principle, the physical-virtual equity principle, perception and action instead of “input” and “output,” and activity-centeredness. A situative space model is proposed based on some of these principles. It is intended to capture what a specific human agent can perceive and not perceive, reach and not reach at any given moment in time. The situative space model is for the egocentric interaction paradigm what the virtual desktop is for the WIMP interaction paradigm: more or less everything of interest to a specific human agent is assumed and supposed to happen here. In addition, the conception and implementation of the easy ADL ecology based on egocentric interaction, comprising of smart objects, a personal activity-centric middleware, ambient intelligence applications aimed at everyday activity support, and a human agent literally in the middle of it all is described. The middleware was developed to address important challenges in ambient intelligence: (1) tracking and managing smart objects; (2) tracking a human agent’s situative spaces; (3) recognizing human activities and actions; (4) managing and facilitating human-environment interaction; and (5) to ease up the development of ambient intelligence applications. The easy ADL ecology was first simulated in immersive virtual reality, and then set up physically as a living laboratory to evaluate: (1) the technological and technical performance of individual middleware components, (2) to perform a user experience evaluation assessing various aspects of user satisfaction in relation to the support offered by the easy ADL ecology, and (3) to use it as a research test bed for addressing challenges in ambient intelligence. While it is problematic to directly compare the “proof-of-concept” easy ADL ecology with related research efforts, it is clear from the user experience evaluation that the subjects were positive with the services it offered.
easy ADL project

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Ostell, Carol. "Individual differences in egocentric orientation." Thesis, University of York, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325649.

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Hipiny, Irwandi. "Egocentric activity recognition using gaze." Thesis, University of Bristol, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.682564.

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When coupled with an egocentric camera, a gaze tracker provides the image point of where the person is fixating at. While performing a familiar task, we tend to fixate on activity- relevant objects at the points in time required in the task at hand. The resulting sequence of gaze regions is therefore very useful for inferring the subject 's activity and action class. This thesis addresses the problem of visual recognition of human activity and action from an egocentric point of view. The higher level task of activity recognition is based on processing the entire sequence of gaze regions as users perform tasks such as cooking or assembling objects, while the mid-level task of action recognition , such as pouring into a cup, is addressed via the automatic segmentation of mutually exclusive sequences prior to recognition. Temporal segmentation is performed by tracking two motion based features inside the successive gaze regions. These features model the underlying structure of image motion data at natural temporal cuts. This segmentation is further improved by the incorporation of a 2D color histogram based detection of human hands inside gaze regions . The proposed method learns activity and action models from the sequence of gaze regions. Activities are learned as a bag of visual words, however we introduce a multi-voting scheme to reduce the effect of noisy matching. Actions are, in addition, modeled as a string of visual words which enforces the structural constraint of an action. We introduce contextual information in the form of location based priors. Furthermore, this thesis addresses the problem of measuring task performance from gaze region modeling. The hypothesis is that subjects with greater task performance scores demonstrate specific gaze patterns as they conduct the task, which is expected to indicate the presence of domain knowledge. This may be reflected in for example requiring minimal visual feedback during the completion of a task. This consistent and strategic use of gaze produces nearly identical activity models among those that score higher, whilst a greater variation is observed between models learned from subjects that have performed less well in the given task. Results are shown on datasets captured using an egocentric gaze tracker with two cameras, a frontal facing camera that captures the scene, and an inward facing camera that tracks the movement of the pupil to estimate the subject's gaze fixation. Our activity and action recognition results are comparable to current literature in egocentric activity recognition, and to the best of our knowledge, the results from the task performance evaluation are the first steps towards automatically modeling user performance from gaze patterns.

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Sundaram, Sudeep. "Egocentric activity recognition on the move." Thesis, University of Bristol, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617591.

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Advances in the design and efficiency of cameras, combined with a significant increase in computational capabilities of machines, have directly resulted in the rapid evolution of computer vision systems. Cameras, which capture all texture, objects and motion in their field of view, provide tremendous potential as wearable sensors that provide aid in daily living. Given the advantages associated with visual sensors, they have been surprisingly under-used as wearables on the move. This thesis addresses the problem of visual recognition of human activity on the move from an egocentric point of view. The problem of perceived motion in the background brought about by the use of moving cameras, is handled by a novel method for background subtraction. Once foreground motion has been disambiguated, a unique representation of actions as collections of smaller space-time volumes is presented, using which two novel methods are proposed for the recognition of egocentric and external actions. The element of context plays a. vital role in complete understanding of human activities. This aspect is addressed through the recognition of user location using a Simultaneous Localisation and Mapping system. Activities and locations are modelled in a complementary manner, such that knowledge of what happens where enhances mapping of large environments and also increases accuracy of activity recognition. The combination of action recognition and location recognition is applied for sequential recognition of activities in continuous video, which in turn opens doors to applications such as life logging and activity retrieval. Results arc shown on datasets captured using a shoulder-worn camera as a solitary sensor. Although the proposed methods outperform the state of the art in egocentric visual activity recognition, it remains a. significant first step towards truly autonomous wearable assistance.

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Herlihey, Tracey A. "Optic flow, egocentric direction and walking." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/54390/.

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This research explored two aspects of visually guided walking (1) what is the role of optic flow in the recalibration of misperceived direction while walking, and (2) how does a change in perceived direction map onto a change in walking direction. Data from five studies investigating adaptation to displaced direction (by prism glasses) suggested the following. First, optic flow is important in the recalibration of perceived direction. Further, processing optic flow is attentionally demanding, such that when cognitive load is increased, recalibration decreases. The results also demonstrated that the timecourse of recalibration changed as a function of the presence, or absence, of optic flow. With regards to the relationship between egocentric direction and walking direction, we demonstrated that a change in visual straight ahead could be mapped onto a change in target-heading error. We found that this relationship held when we unpacked the data according to the direction of displacement to which observers were exposed. The important relationship between visually perceived direction and walking direction was also highlighted in a patient study, using patients whose perception of direction was endogenously shifted after a right hemisphere stroke. Taken together, the results of this thesis help to highlight the role of optic flow in the recalibration of perceived direction, and the role of perceived direction in the visual guidance of walking. It is argued that optic flow promotes rapid recalibration of visual direction, and that change in perceived visual straight ahead can be mapped onto a changed in walking direction.

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Aghaei, Maedeh. "Social Signal Processing from Egocentric Photo-Streams." Doctoral thesis, Universitat de Barcelona, 2018. http://hdl.handle.net/10803/650918.

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Wearable photo-cameras offer a hands-free way to record images from the camera- wearer perspective of daily experiences as they are lived, without the necessity to interrupt recording due to the device battery or storage limitations. This stream of images, known as egocentric photo-streams, contains important visual data about the living of the user, where social events among them are of special interest. Social interactions are proven to be a key to longevity and having too few interactions equates the same risk factor as smoking regularly. Considering the importance of the matter, there is no wonder that automatic analysis of social interactions is largely attracting the interest of the scientific community. Analysis of unconstrained photo-streams however, imposes novel challenges to the social signal processing problem with respect to conventional videos. Due to the free motion of the camera and to its low temporal resolution, abrupt changes in the field of view, in illumination condition and in the target location are highly frequent. Also, since images are acquired under real-world conditions, occlusions occur regularly and appearance of the people undergoes intensive variations from one event to another. Given a user wearing a photo-camera during a determined period, this thesis, driven by the social signal processing paradigm presents a framework for comprehensive social pattern characterization of the user. In social signal processing, the second step after recording the scene is to track the appearance of multiple people who are involved in the social events. Hence, our proposal begins by introducing a multi-face tracking which holds certain characteristics to deal with challenges imposed by the egocentric photo-streams. Next step forward in social signal processing, is to extract the so-called social signals from the tracked people. In this step, besides the conventionally studied social signals, clothing as a novel social signal is proposed for further studies within the social signal processing. Finally, the last step is social signal analysis, itself. In this thesis, social signal analysis is essentially defined as reaching an understanding of social patterns of a wearable photo-camera user by reviewing captured photos by the worn camera over a period of time. Our proposal for social signal analysis is comprised of first, to detect social interactions of the user where the impact of several social signals on the task is explored. The detected social events are inspected in the second step for categorization into different social meetings. The last step of the framework is to characterize social patterns of the user. Our goal is to quantify the duration, the diversity and the frequency of the user social relations in various social situations. This goal is achieved by the discovery of recurrences of the same people across the whole set of social events related to the user. Each step of our proposed pipeline is validated over relevant datasets, and the obtained results are reported quantitatively and qualitatively. For each section of the pipeline, a comparison with related state-of-the-art models is provided. A discussion section over the obtained results is also given which is dedicated to highlighting the advantages, shortcomings, and differences of the proposed models, and with regards to the state-of-the-art.
Las cámaras portables ofrecen una forma de capturar imágenes de experiencias diarias vividas por el usuario, desde su propia perspectiva y sin la intervención de éste, sin la necesidad de interrumpir la grabación debido a la batería del dispositivo o las limitaciones de almacenamiento. Este conjunto de imágenes, conocidas como secuencias de fotos egocéntricas, contiene datos visuales importantes sobre la vida del usuario, donde entre ellos los eventos sociales son de especial interés. Las interacciones sociales han demostrado ser clave para la longevidad, el tener pocas interacciones equivale al mismo factor de riesgo que fumar regularmente. Teniendo en cuenta la importancia del asunto, no es de extrañar que el análisis automático de las interacciones sociales atraiga en gran medida el interés de la comunidad científica. Sin embargo, el análisis de secuencias de fotos impone nuevos desafíos al problema del procesamiento de las señales sociales con respecto a los videos convencionales. Debido al movimiento libre de la cámara y a su baja resolución temporal, los cambios abruptos en el campo de visión, en la iluminación y en la ubicación del objeto son frecuentes. Además, dado que las imágenes se adquieren en condiciones reales, las oclusiones ocurren con regularidad y la apariencia de las personas varía de un evento a otro. Dado que un individuo usa una cámara fotográfica durante un período determinado, esta tesis, impulsada por el paradigma del procesamiento de señales sociales, presenta un marco para la caracterización integral del patrón social de dicho individuo. En el procesamiento de señales sociales, el segundo paso después de grabar la escena es rastrear la apariencia de varias personas involucradas en los eventos sociales. Por lo tanto, nuestra propuesta comienza con la introducción de un seguimiento de multiples caras que posee ciertas características para hacer frente a los desafíos impuestos por las secuencias de fotos egocéntricas. El siguiente paso en el procesamiento de señales sociales es extraer las señales sociales de las personas bajo análisis. En este paso, adema´s de las señales sociales estudiadas convencionalmente, en esta tesis se propone la vestimenta como una nueva señal social para estudios posteriores dentro del procesamiento de señales sociales. Finalmente, el último paso es el análisis de señales sociales. En esta tesis, el análisis de señales sociales se define esencialmente como la comprensión de los patrones sociales de un usuario de cámara portable, mediante la revisión de fotos capturadas por la cámara llevada durante un período de tiempo. Nuestra propuesta para el análisis de señales sociales se compone de diferentes pasos. En primer lugar, detectar las interacciones sociales del usuario donde se explora el impacto de varias señales sociales en la tarea. Los eventos sociales detectados se inspeccionan en el segundo paso para la categorización en diferentes reuniones sociales. El último paso de la propuesta es caracterizar los patrones sociales del usuario. Nuestro objetivo es cuantificar la duración, la diversidad y la frecuencia de las relaciones sociales del usuario en diversas situaciones sociales. Este objetivo se logra mediante el descubrimiento de apariciones recurrentes de personas en todo el conjunto de eventos sociales relacionados con el usuario. Cada paso de nuestro método propuesto se valida sobre conjuntos de datos relevantes, y los resultados obtenidos se evalúan cuantitativa y cualitativamente. Cada etapa del modelo se compara con los trabajos relacionados más recientes. También, se presenta una sección de discusión sobre los resultados obtenidos, que se centra en resaltar las ventajas, limitaciones y diferencias de los modelos propuestos, y de estos con respecto al estado del arte.

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Cartas, Ayala Alejandro. "Recognizing Action and Activities from Egocentric Images." Doctoral thesis, Universitat de Barcelona, 2020. http://hdl.handle.net/10803/670752.

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Egocentric action recognition consists in determining what a wearable camera user is doing from his perspective. Its defining characteristic is that the person himself is only partially visible in the images through his hands. As a result, the recognition of actions can rely solely on user interactions with objects, other people, and the scene. Egocentric action recognition has numerous assistive technology applications, in particular in the field of rehabilitation and preventive medicine. The type of egocentric camera determines the activities or actions that can be predicted. There are roughly two kinds: lifelogging and video cameras. The former can continuously take pictures every 20-30 seconds during day-long periods. The sequences of pictures produced by them are called visual lifelogs or photo-streams. In comparison with video, they lack of motion that typically has been used to disambiguate actions. We present several egocentric action recognition approaches for both settings. We first introduce an approach that classifies still-images from lifelogs by combining a convolutional network and a random forest. Since lifelogs show temporal coherence within consecutive images, we also present two architectures that are based on the long short-term memory (LSTM) network. In order to thoroughly measure their generalization performance, we introduce the largest photo-streams dataset for activity recognition. These tests not only consider hidden days and multiple users but also the effect of time boundaries from events. We finally present domain adaptation strategies for dealing with unknown domain images in a real-world scenario. Our work on egocentric action recognition from videos is primarily focused on object-interactions. We present a deep network that in the first level models person to-object interactions, and in the second level models sequences of actions as part of a single activity. The spatial relationship between hands and objects is modeled using a region-based network, whereas the actions and activities are modeled using a hierarchical LSTM. Our last approach explores the importance of audio produced by the egocentric manipulations of objects. It combines a sparse temporal sampling strategy with a late fusion of audio, RGB, and temporal streams. Experimental results on the EPIC-Kitchen dataset show that multimodal integration leads to better performance than unimodal approaches.
El reconeixement d’accions egocèntriques consisteix a determinar què fa un usuari de càmera egocèntrica des de la seva perspectiva. La característica fonamental que defineix aquesta tasca és que la persona mateixa només és parcialment visible: a les imatges només veurem les seves mans. Com a resultat, el reconeixement d’accions pot dependre únicament de les interaccions dels usuaris amb objectes, altres persones i l’escena mitjançant les seves mans. El reconeixement d’acció egocèntrica té nombroses aplicacions tecnològiques d’assistència, en particular en el camp de la rehabilitació i la medicina preventiva. El tipus de càmera egocèntrica determina les activitats o les accions que es poden predir. Hi ha, grosso modo, dos tipus: registre de vida i càmeres de vídeo. Les càmeres de registre de vida poden prendre fotografies cada 20-30 segons de manera continuada durant tot el dia. Les seqüències d'imatges produïdes per aquestes s'anomenen visual lifelogs o photo-streams. En comparació amb el vídeo, manquen de moviment, el qual normalment es fa servir per desambiguar les accions. Presentem múltiples propostes per a reconeixement d’acció egocèntrica en ambdós contextos. Primer introduïm una proposta per classificar les imatges fixes dels registres de vida combinant una xarxa convolucional i un random forest. Com que els registres de vida mostren coherència temporal en imatges consecutives, també presentem dues arquitectures basades en una xarxa de long short-term memory (LSTM). Per mesurar a fons el seu rendiment de generalització, presentem la base de dades més gran de seqüències de fotos per al reconeixement d’activitats. Aquestes proves no només tenen en compte els dies ocults i diversos usuaris, sinó també l’efecte de les fronteres temporals dels diferents esdeveniments. Finalment presentem estratègies d’adaptació de dominis per tractar imatges de domini desconegut en un escenari del món real. El nostre treball sobre el reconeixement d’accions egocèntriques a partir de vídeos se centra principalment en les interaccions amb objectes. Presentem una xarxa profunda que en el primer nivell modela les interaccions entre persona i objecte i en el segon nivell modela les seqüències d’accions com a part d’una única activitat. La relació espacial entre mans i objectes es modela mitjançant una xarxa basada en regions, mentre que les accions i activitats es modelen mitjançant una xarxa LSTM jeràrquica. La nostra darrera proposta explora la importància de l'àudio produït per les manipulacions egocèntriques d'objectes. Combina una estratègia de mostreig temporal escassa amb una fusió tardana d’àudio, RGB i fluxos temporals. Els resultats experimentals sobre la base de dades EPIC-Kitchen mostren que la integració multimodal resulta en un millor rendiment que els plantejaments unimodals.

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Tamir, Diana Ilse. "A Social Neuroscience Perspective on Egocentric Influence." Thesis, Harvard University, 2014. http://dissertations.umi.com/gsas.harvard:11523.

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This dissertation explores the cognitive mechanisms and motivations that guide two aspects of human social behavior: thinking about other's experiences and communicating with others. In both cases, studies investigated the possibility that self-referential thought guides our social behavior. First, Paper 1 and 2 investigated how people come to understand other's thoughts and experiences by suggesting that people may use their own self-knowledge as a starting point for making inferences about others. Using functional magnetic resonance imaging and behavioral measures, these studies tested whether individuals make social inferences using the cognitive process of egocentric anchoring-and-adjustment, whereby individuals first anchor on self-knowledge, and then serially adjust away from these anchors in order to correct for differences between the self and other. Results provided evidence consistent with egocentric anchoring-and-adjustment: increases in self-other discrepancy corresponded to both increases in activity in the MPFC (Paper 1), a neural region associated with both self-referential thought and social cognition, as well as increases in response time (Paper 2), though only for targets where self-knowledge is particularly relevant. Paper 3 then investigated a prominent social behavior, self-disclosure--the act of sharing information about the self with others--which comprises 30- 40% of human conversation. Using both functional magnetic resonance imaging and behavioral economics methodology, five studies tested whether people communicate their thoughts and feelings to others because they are intrinsically motivated to do so. Results supported the hypothesis that individuals experience sharing their thoughts with others as subjectively rewarding: self-disclosure was associated with increased activation in brain regions that form the mesolimbic dopamine reward system; and individuals were willing to forgo money to self- disclose. Moreover, both the self and the disclosure aspects of self-disclosure independently contributed to its value. Together these Papers contribute to our understanding of the ways in which our internal world grounds elements of our external social acts.
Psychology

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Spera, Emiliano. "Egocentric Vision Based Localization of Shopping Cart." Doctoral thesis, Università di Catania, 2019. http://hdl.handle.net/10761/4139.

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Indoor camera localization from egocentric images is a challenge computer vision problem which has been strongly investigated in the last years. Localizing a camera in a 3D space can open many useful applications in different domains. In this work, we analyse this challenge to localize shopping cart in stores. Three main contributions are given with this thesis. As first, we propose a new dataset for shopping cart localization which includes both RGB and depth images together with the 3-DOF data corresponding to the cart position and orientation in the store. The dataset is also labelled with respect to 16 different classes associated to different areas of the considered retail. A second contribution is related to a benchmark study where different methods are compared for both, cart pose estimation and retail area classification. Last contribution is related to the computational analysis of the considered approaches.

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Boutaleb, Mohamed Yasser. "Egocentric Hand Activity Recognition : The principal components of an egocentric hand activity recognition framework, exploitable for augmented reality user assistance." Electronic Thesis or Diss., CentraleSupélec, 2022. http://www.theses.fr/2022CSUP0007.

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Les êtres humains utilisent leurs mains pour diverses tâches dans la vie quotidienne et professionnelle, ce qui fait que la recherche dans ce domaine a récemment suscitée un grand intérêt. De plus, l'analyse et l'interprétation du comportement humain à l'aide de signaux visuels est l'un des domaines les plus actifs et les plus explorés de la vision par ordinateur. Avec l'arrivée des nouvelles technologies de réalité augmentée, les chercheurs s'intéressent de plus en plus à la compréhension de l'activité de la main d'un point de vue de la première personne, en explorant la pertinence de son utilisation pour le guidage et l'assistance humaine.L'objectif principal de cette thèse est de proposer un système de reconnaissance de l'activité de l'utilisateur incluant quatre composants essentiels, qui peut être utilisé pour assister les utilisateurs lors d'activités orientées vers des objectifs spécifiques : industrie 4.0 (par exemple, assemblage assisté, maintenance) et enseignement. Ainsi, le système observe les mains de l'utilisateur et les objets manipulés depuis le point de vue de l'utilisateur afin de reconnaître et comprendre ses activités manuelles réalisées. Le système de réalité augmenté souhaité doit reconnaître de manière robuste les activités habituelles de l'utilisateur. Néanmoins, il doit détecter les activités inhabituelles afin d'informer l'utilisateur et l'empêcher d'effectuer de mauvaises manœuvres, une exigence fondamentale pour l'assistance à l'utilisateur. Cette thèse combine donc des techniques issues des domaines de recherche de la vision par ordinateur et de l'apprentissage automatique afin de proposer des composants de reconnaissance de l'activité de l'utilisateur nécessaires à un outil d'assistance complet
Humans use their hands for various tasks in daily life and industry, making research in this area a recent focus of significant interest. Moreover, analyzing and interpreting human behavior using visual signals is one of the most animated and explored areas of computer vision. With the advent of new augmented reality technologies, researchers are increasingly interested in hand activity understanding from a first-person perspective exploring its suitability for human guidance and assistance. Our work is based on machine learning technology to contribute to this research area. Recently, deep neural networks have proven their outstanding effectiveness in many research areas, allowing researchers to jump significantly in efficiency and robustness.This thesis's main objective is to propose a user's activity recognition framework including four key components, which can be used to assist users during their activities oriented towards specific objectives: industry 4.0 (e.g., assisted assembly, maintenance) and teaching. Thus, the system observes the user's hands and the manipulated objects from the user's viewpoint to recognize his performed hand activity. The desired framework must robustly recognize the user's usual activities. Nevertheless, it must detect unusual ones to feedback and prevent him from performing wrong maneuvers, a fundamental requirement for user assistance. This thesis, therefore, combines techniques from the research fields of computer vision and machine learning to propose comprehensive hand activity recognition components essential for a complete assistance tool

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Garcia-Hernando, Guillermo. "Understanding egocentric human actions with temporal decision forests." Thesis, Imperial College London, 2017. http://hdl.handle.net/10044/1/63825.

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Understanding human actions is a fundamental task in computer vision with a wide range of applications including pervasive health-care, robotics and game control. This thesis focuses on the problem of egocentric action recognition from RGB-D data, wherein the world is viewed through the eyes of the actor whose hands describe the actions. The main contributions of this work are its findings regarding egocentric actions as described by hands in two application scenarios and a proposal of a new technique that is based on temporal decision forests. The thesis first introduces a novel framework to recognise fingertip writing in mid-air in the context of human-computer interaction. This framework detects whether the user is writing and tracks the fingertip over time to generate spatio-temporal trajectories that are recognised by using a Hough forest variant that encourages temporal consistency in prediction. A problem with using such forest approach for action recognition is that the learning of temporal dynamics is limited to hand-crafted temporal features and temporal regression, which may break the temporal continuity and lead to inconsistent predictions. To overcome this limitation, the thesis proposes transition forests. Besides any temporal information that is encoded in the feature space, the forest automatically learns the temporal dynamics during training, and it is exploited in inference in an online and efficient manner achieving state-of-the-art results. The last contribution of this thesis is its introduction of the first RGB-D benchmark to allow for the study of egocentric hand-object actions with both hand and object pose annotations. This study conducts an extensive evaluation of different baselines, state-of-the art approaches and temporal decision forest models using colour, depth and hand pose features. Furthermore, it extends the transition forest model to incorporate data from different modalities and demonstrates the benefit of using hand pose features to recognise egocentric human actions. The thesis concludes by discussing and analysing the contributions and proposing a few ideas for future work.

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Rana, Juwel. "On weighted egocentric graphs and social group communication." Doctoral thesis, Luleå tekniska universitet, Datavetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-17932.

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Electronic communication has a profound impact on our society, where for instance social media now is almost ubiquitously used to share information. This has led to several major challenges, including how to overcome information overload and privacy concerns, how to utilize social context based on multiple data sources from both the virtual and physical worlds, and subsequently how to improve group communication.This doctoral thesis presents an Aggregated Social Graph (ASG) framework that utilizes weighted egocentric graphs representing the calculated social strength between people. The framework is based on a unified interaction model that support capturing and aggregating information from communication services such as social networks, mobile phones and email clients. Two algorithms for social strength computation are presented and evaluated in this thesis: Utility Function and Euclidean Distance.The proposed framework contains a social recommender engine that includes context-based methods (tags, locations and objects) to rank, filter, recommend and group social contacts and information based on the weighted egocentric graphs. The ranking of contacts can for instance be used to automatically form contextual groups. These groups can be used to dynamically compose and tailor communication tools for specific communication contexts by integrating widgets into web-based collaborative environments.The framework also contains a novel social distribution mechanism for controlling otherwise flat or viral distribution of information. The mechanism combine weighted egocentric graphs and users' context to establish a level of trust to control propagation of information, thus reducing the potential perception of spamming.The work is evaluated through several proof-of-concept prototypes that show the potential to improve distribution and filtering of information as well as social group formation. The proof-of-concept prototypes also show that communication tools can be dynamically composed for a specific group of users and for a specific context. Moreover, this thesis presents evaluation studies that compare the social strength algorithms and verify the concept of contextual group formation.In conclusion, utilizing social context as represented by weighted egocentric graphs has the potential to improve group communication services. We believe that the proposed framework is an effective means to reduce the problems with information overload and to enable automation of processes related to electronic group communication.

Godkänd; 2013; 20130925 (mjrana); Tillkännagivande disputation 2013-10-04 Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Juwel Rana Ämne: Distribuerade datorsystem/Pervasive Mobile Computing Avhandling: On Weighted Egocentric Graphs and Social Group Communication Opponent: Associate Professor Georg Groh, Fakultätsrat der Fakultät für Informatik, Technische Universität München, Garching, Germany Ordförande: Professor Christer Åhlund, Institutionen för system- och rymdteknik, Luleå tekniska universitet Tid: Måndag den 28 oktober 2013, kl 13.00 Plats: A109, Luleå tekniska universitet

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Merrill, Kim Ann 1965. "The relationship between egocentric tendencies and marital satisfaction." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/277301.

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This study was designed to investigate if adults demonstrate egocentric-tendencies, and if so, what factors influence the degree of egocentrism displayed. The investigation was also devised in order to determine if there is a relation between the degree of egocentric-tendencies displayed and marital satisfaction. To measure egocentrism in adults, the Adult Egocentric-Tendency Scale (AETS) was developed. Both the Kansas Marital Satisfaction Scale and the Marriage Rating Scale were utilized to assess marital satisfaction and functioning. One-hundred-thirty-six (N = 136) first time married individuals from the general population acted as participants. They were administered all three instruments. Findings indicate that egocentric-tendencies are measurable in adults. Furthermore, specific adults (men, those who are highly educated and those with a lower number of children living in the household) tend to display greater degrees of egocentrism. This investigation also uncovered a tendency for marital satisfaction to decrease as egocentrism increases and vice versa. Other factors contributing to marital satisfaction were also explored.

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Millett, Matthew E. 1971. "The Egocentric Map Perspective in Thematic Choropleth Maps." Thesis, University of Oregon, 2010. http://hdl.handle.net/1794/10832.

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xii, 80 p. : ill., maps (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number.
Choropleth maps are a popular way of depicting spatial data. The map communication model, which theorizes that geographic information is transmitted from the cartographer to the map user via a map, suggests that cartographers are responsible for clearly conveying spatial data in a way all map users can understand. Map users, however, come from different places and may harbor certain regional biases. This thesis investigates whether map users tend to focus on data patterns within their home regions during the visual-search and decision-making processes when reading classed choropleth maps, thereby exhibiting an egocentric map behavior. Seventy-one subjects took a computer-based test asking them to identify various phenomena on a series of choropleth maps of the lower 48 states. The results show a weak positive effect of egocentric map behavior; subjects who lived in a particular state longer were slightly more likely to choose states nearby their home region.
Committee in Charge: Dr. Amy Lobben, Chair; Dr. Dan Gavin

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Bolaños, Solà Marc. "Deep Multimodal Learning for Egocentric Storytelling and Food Analysis." Doctoral thesis, Universitat de Barcelona, 2021. http://hdl.handle.net/10803/671672.

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The world of Machine Learning and Computer Vision has experienced a revolution since the last years. The appearance of Deep Learning algorithms and Convolutional Neural Networks, altogether with the increased processing capabilities provided by modern GPUs and the enormous amounts of annotated data publicly available, have allowed a boost in the field as never seen before. These notable improvements achieved in the Machine Learning world have led to the appearance of new fields like the Multimodal Learning, which encompasses and learns from many subfields. Additionally, new applications have taken profit of these advancements in order to reach high levels of performance. The huge results improvement of the currently available algorithms have allowed not only revolutionizing the academic world, but also bringing AI-based solutions to the market that looked like science fiction barely 10 years ago. This thesis, which is written as a papers compendium, focuses on delving deeper into the novel topic of Deep Multimodal Learning by proposing new algorithms and solutions for both already existing and newly defined problems. From the applications perspective, most of the papers presented can be divided in two areas of applicability. From the one hand, Egocentric Vision and Storytelling, which consists in acquiring images from the daily life of a person in order to analyse its behaviour patterns like social interactions, activities and events, interactions with objects, etc. And on the other hand, Food Recognition and Analysis, which consists in visually analysing and recognizing the food appearing on images in multiple contexts and with different levels of complexity, from food groups recognition to nutritional analysis. In both applications, the final purpose of the proposed papers is building tools that provide information that could lead to a better quality of life of the users.
El mundo del Machine Learning y la Visión por Computador ha experimentado una revolución los últimos años. La aparición de algoritmos de Deep Learning y Convolutional Neural Networks, junto con las mayores capacidades de procesamiento proporcionadas por GPU modernas y las enormes cantidades de datos anotados disponibles públicamente, han permitió un impulso en el campo como nunca antes se había visto.Estas notables mejoras logradas en el mundo del Machine Learning han llevado a la aparición de nuevos campos como el Aprendizaje Multimodal, que engloba y aprende de muchos subcampos. Además, nuevas aplicaciones han aprovechado estos avances para alcanzar altos niveles de rendimiento. La enorme mejora en los resultados de los algoritmos disponibles actualmente ha permitido no solo revolucionar el mundo académico, sino también llevar al mercado soluciones basadas en IA que parecían ciencia ficción hace apenas 10 años.Esta tesis, que está escrita como un compendio de artículos, se enfoca en profundizar en el novedoso tema del Aprendizaje Multimodal Profundo al proponer nuevos algoritmos y soluciones para problemas ya existentes y recientemente definidos. Desde la perspectiva de las aplicaciones, la mayoría de los trabajos presentados se pueden dividir en dos áreas de aplicabilidad. Por un lado, la Visión Egocéntrica y el Storytelling, que consiste en la adquisición de imágenes de la vida diaria de una persona para analizar su comportamiento y extraer patrones asociadas a estos como por ejemplo interacciones sociales, actividades y eventos, interacciones con objetos, etc. Y por otro lado, el Reconocimiento y Análisis de Alimentos, que consiste en visualmente analizar y reconocer la comida que aparece en imágenes en múltiples contextos y con diferentes niveles de complejidad, desde el reconocimiento de grupos de alimentos hasta el análisis nutricional.En ambas aplicaciones, el propósito final de los artículos propuestos es construir herramientas que brinden información que pueda conducir a una mejor calidad de vida de los usuarios.

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Jones, James Adam. "Egocentric depth perception in optical see-through augmented reality." Master's thesis, Mississippi State : Mississippi State University, 2007. http://library.msstate.edu/etd/show.asp?etd=etd-07062007-002245.

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Desrocher, Mary Ellen. "Dissociations of egocentric and allocentric spatial memory, evidence from aging." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0003/NQ35144.pdf.

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Fathi, Alireza. "Learning descriptive models of objects and activities from egocentric video." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/48738.

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Recent advances in camera technology have made it possible to build a comfortable, wearable system which can capture the scene in front of the user throughout the day. Products based on this technology, such as GoPro and Google Glass, have generated substantial interest. In this thesis, I present my work on egocentric vision, which leverages wearable camera technology and provides a new line of attack on classical computer vision problems such as object categorization and activity recognition. The dominant paradigm for object and activity recognition over the last decade has been based on using the web. In this paradigm, in order to learn a model for an object category like coffee jar, various images of that object type are fetched from the web (e.g. through Google image search), features are extracted and then classifiers are learned. This paradigm has led to great advances in the field and has produced state-of-the-art results for object recognition. However, it has two main shortcomings: a) objects on the web appear in isolation and they miss the context of daily usage; and b) web data does not represent what we see every day. In this thesis, I demonstrate that egocentric vision can address these limitations as an alternative paradigm. I will demonstrate that contextual cues and the actions of a user can be exploited in an egocentric vision system to learn models of objects under very weak supervision. In addition, I will show that measurements of a subject's gaze during object manipulation tasks can provide novel feature representations to support activity recognition. Moving beyond surface-level categorization, I will showcase a method for automatically discovering object state changes during actions, and an approach to building descriptive models of social interactions between groups of individuals. These new capabilities for egocentric video analysis will enable new applications in life logging, elder care, human-robot interaction, developmental screening, augmented reality and social media.

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Chen, Longfei. "Analysis and Modeling of Machine Operation Tasks using Egocentric Vision." Kyoto University, 2020. http://hdl.handle.net/2433/259046.

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Frank, Christopher E. "An Egocentric Spatial Data Model for Intelligent Mobile Geographic Information Systems." Fogler Library, University of Maine, 2003. http://www.library.umaine.edu/theses/pdf/FrankCE2003.pdf.

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Upshaw, Jennifer. "Allocentric vs. egocentric neglect in stroke patients : the impact on functional outcomes." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/59112.

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Objective: Few studies have investigated the assessment, frequency, and functional impact of egocentric and allocentric neglect among stroke patients. This study aimed to determine a) whether allocentric and egocentric neglect could be dissociated among a sample of stroke patients using eye-tracking technology, b) the frequencies of each neglect subtype and c) the nature of the relationship between neglect subtype and functional outcome. Method: Sixteen acute stroke patients were administered comprehensive neuropsychological (NP) assessment batteries, a pencil-and-paper Apples Test, and an eye-tracking measure of neglect subtype. Descriptive analyses were conducted on Apples Test and eye-tracking scores to determine their sensitivities in detecting neglect subtype. Hierarchical regression was used to determine predictive utility of the eye-tracking measure above that of both NP test performance and Apples Test neglect scores. ANOVA was used to investigate the relationships between neglect subtype and functional outcome. Results: The eye-tracking measure was more sensitive in identifying neglect subtype in patients than the traditional pen and paper Apples Test. Classification of neglect subtype based on eye-tracking performance was a significant predictor of functional outcome beyond that accounted for by both NP test performance and traditional Apples Test neglect classification. Patients with no neglect symptoms had superior functional outcomes compared to patients with either or both types of neglect. Patients with both types of neglect had significantly poorer functional outcomes than those with either subtype, or no neglect. Functional outcomes of patients with either allocentric or egocentric neglect did not differ significantly from each other. Conclusion: Neglect subtype classification contributes independently to the prediction of functional status above and beyond that of neuropsychological test performance, and is a better predictor of function than traditional measures of allocentric and egocentric neglect. The significant relationship between neglect subtype and functional outcome highlights the importance of sensitive assessment and identification of neglect subtype amongst stroke patients to better predict prognosis and inform improved rehabilitative treatment planning.
Irving K. Barber School of Arts and Sciences (Okanagan)
Psychology, Department of (Okanagan)
Graduate

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Parslow, David M. "An investigation into the neural correlates of egocentric and allocentric spatial memory." Thesis, King's College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.404317.

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Alameda-Pineda, Xavier. "Egocentric Audio-Visual Scene Analysis : a machine learning and signal processing approach." Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENM024/document.

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Depuis les vingt dernières années, l'industrie a développé plusieurs produits commerciaux dotés de capacités auditives et visuelles. La grand majorité de ces produits est composée d'un caméscope et d'un microphone embarqué (téléphones portables, tablettes, etc). D'autres, comme la Kinect, sont équipés de capteurs de profondeur et/ou de petits réseaux de microphones. On trouve également des téléphones portables dotés d'un système de vision stéréo. En même temps, plusieurs systèmes orientés recherche sont apparus (par exemple, le robot humanoïde NAO). Du fait que ces systèmes sont compacts, leurs capteurs sont positionnés près les uns des autres. En conséquence, ils ne peuvent pas capturer la scène complète, mais qu'un point de vue très particulier de l'interaction sociale en cours. On appelle cela "Analyse Égocentrique de Scènes Audio-Visuelles''.Cette thèse contribue à cette thématique de plusieurs façons. D'abord, en fournissant une base de données publique qui cible des applications comme la reconnaissance d'actions et de gestes, localisation et suivi d'interlocuteurs, analyse du tour de parole, localisation de sources auditives, etc. Cette base a été utilisé en dedans et en dehors de cette thèse. Nous avons aussi travaillé le problème de la détection d'événements audio-visuels. Nous avons montré comme la confiance en une des modalités (issue de la vision en l'occurrence), peut être modélisée pour biaiser la méthode, en donnant lieu à un algorithme d'espérance-maximisation visuellement supervisé. Ensuite, nous avons modifié l'approche pour cibler la détection audio-visuelle d'interlocuteurs en utilisant le robot humanoïde NAO. En parallèle aux travaux en détection audio-visuelle d'interlocuteurs, nous avons développé une nouvelle approche pour la reconnaissance audio-visuelle de commandes. Nous avons évalué la qualité de plusieurs indices et classeurs, et confirmé que l'utilisation des données auditives et visuelles favorise la reconnaissance, en comparaison aux méthodes qui n'utilisent que l'audio ou que la vidéo. Plus tard, nous avons cherché la meilleure méthode pour des ensembles d'entraînement minuscules (5-10 observations par catégorie). Il s'agit d'un problème intéressant, car les systèmes réels ont besoin de s'adapter très rapidement et d'apprendre de nouvelles commandes. Ces systèmes doivent être opérationnels avec très peu d'échantillons pour l'usage publique. Pour finir, nous avons contribué au champ de la localisation de sources sonores, dans le cas particulier des réseaux coplanaires de microphones. C'est une problématique importante, car la géométrie du réseau est arbitraire et inconnue. En conséquence, cela ouvre la voie pour travailler avec des réseaux de microphones dynamiques, qui peuvent adapter leur géométrie pour mieux répondre à certaines tâches. De plus, la conception des produits commerciaux peut être contrainte de façon que les réseaux linéaires ou circulaires ne sont pas bien adaptés
Along the past two decades, the industry has developed several commercial products with audio-visual sensing capabilities. Most of them consists on a videocamera with an embedded microphone (mobile phones, tablets, etc). Other, such as Kinect, include depth sensors and/or small microphone arrays. Also, there are some mobile phones equipped with a stereo camera pair. At the same time, many research-oriented systems became available (e.g., humanoid robots such as NAO). Since all these systems are small in volume, their sensors are close to each other. Therefore, they are not able to capture de global scene, but one point of view of the ongoing social interplay. We refer to this as "Egocentric Audio-Visual Scene Analysis''.This thesis contributes to this field in several aspects. Firstly, by providing a publicly available data set targeting applications such as action/gesture recognition, speaker localization, tracking and diarisation, sound source localization, dialogue modelling, etc. This work has been used later on inside and outside the thesis. We also investigated the problem of AV event detection. We showed how the trust on one of the modalities (visual to be precise) can be modeled and used to bias the method, leading to a visually-supervised EM algorithm (ViSEM). Afterwards we modified the approach to target audio-visual speaker detection yielding to an on-line method working in the humanoid robot NAO. In parallel to the work on audio-visual speaker detection, we developed a new approach for audio-visual command recognition. We explored different features and classifiers and confirmed that the use of audio-visual data increases the performance when compared to auditory-only and to video-only classifiers. Later, we sought for the best method using tiny training sets (5-10 samples per class). This is interesting because real systems need to adapt and learn new commands from the user. Such systems need to be operational with a few examples for the general public usage. Finally, we contributed to the field of sound source localization, in the particular case of non-coplanar microphone arrays. This is interesting because the geometry of the microphone can be any. Consequently, this opens the door to dynamic microphone arrays that would adapt their geometry to fit some particular tasks. Also, because the design of commercial systems may be subject to certain constraints for which circular or linear arrays are not suited

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Maskell, John Frederick. "The process of sustainable development, change in emphasis from egocentric values to envirocentric values." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0024/NQ32842.pdf.

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Banzhaf, Christian [Verfasser]. "Empathy in depression: egocentric and altercentric biases and the role of alexithymia / Christian Banzhaf." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2018. http://d-nb.info/1160515646/34.

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Braun, Amanda Ann. "Comparison of the Role of Dopamine in Egocentric and Allocentric Learning, Two Subtypes of Navigation." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439281292.

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Plank, Markus. "Behavioral, Electrocortical and Neuroanatomical Correlates of Egocentric and Allocentric Reference Frames during Visual Path Integration." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-102397.

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Kokotas, Vassilis. "The effects of yoked prisms on body posture and egocentric perception in a normal population." Thesis, Aston University, 2016. http://publications.aston.ac.uk/28744/.

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The principal theme of this thesis is the effect of yoked prisms on body posture and egocentric perception. Yoked prisms have been clinically used in the management of a variety of visual and neuro-motor dysfunctions. Most studies have been conducted in pathological populations by studying the effects of prismatic adaptation, without distinguishing short and long term effects. In this study, postural and perceptual prismatic effects have been studied by preventing prism adaptation. A healthy population was selected in order to investigate the immediate prismatic effects, when there is no obvious benefit from their use for the individual. Posturography was used to assess changes in weight distribution and shifts in centre of pressure (barycentre). In addition, photographic analyses were used to assess effects on posture on the x and z axis. Experiments with space board and visual midline shift were used for the evaluation of spatial perception and egocentric localisation. One pair of 8 Δ yoked prisms base left (BL) and one pair of 8 Δ yoked prisms base up (BU) were applied randomly and compared to a pair of plano lenses. Results suggest that immediate prismatic effects take place on a perceptual level and are reflected on an altered body posture respectively without significant changes in weight distribution. Yoked prisms BL showed a rightward rotational effect on spatial perception by expanding space on the z axis when viewing through the base of the prism and constricting space through the apex of the prism. Body posture responded respectively to what was visually perceived by altering posture. A rightward shift and tilt of the head was recorded along with the hips shift and shoulders tilt in the dame direction. Additionally, right shoulder shifted backwards and an angular midline shift to the right was recorded. The egocentric localisation was affected by shifting the midline perception to the left. Yoked prisms BU resulted on a head shift forward and a reduction of the head-neck angle by bringing the chin closer to the chest. The egocentric localisation was altered on the vertical axis providing subjects the perception that their eye level was higher during the experiment. In conclusion, yoked prisms seemed to induce changes in body posture, mainly in the upper body and head, without any significant changes in weight distribution. These changes are partially reflected in spatial perception tests and egocentric localisation before any prismatic adaptation takes place.

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Lee, Bobby Ann. "COMPARING TWO-YEAR COLLEGES UNDER A COMMON SUSTAINABLE DEVELOPMENT FRAMEWORK: PERSONAL EGOCENTRIC NETWORKS AND PERSPECTIVES." UKnowledge, 2018. https://uknowledge.uky.edu/edsc_etds/39.

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The study purpose is to advance implementation of sustainable development at colleges, and to contribute to organizational change research using social network analysis. The researcher conducted document analysis using 2012-2016 sustainability reports of 16 purposefully selected two-year colleges under a common framework. Interpreting and coding resulted in ranking sustainable development activities as well as grouping colleges using cluster analysis. A survey and interviews were employed by the researcher to determine major themes as challenges to sustainability implementation, and personal network themes using social network analysis measures and sociograms. Challenges to sustainability implementation identified as study themes were: (1) college leadership transition; (2) communication networks; and (3) sustainability funding and resources. Personal network themes based on network analysis were: (1) sustainability leadership typologies; (2) network communication bridges and cliques; and (3) social capital for sustainability funding and resources. The research found personal egocentric network techniques an effective methodology in identifying attributes of communication links to inform transformational leaders implementing innovation. Study implications are that sustainability leaders within informal networks of staff, administrators, and faculty influence and actively participate in innovation diffusion. Faculty and staff work on specific projects and activities advancing sustainability such as community gardens or working with environmental groups, and administrator support provides social capital in terms of funding and resources. Striking the right balance among types and communication ties is a challenge for transformational leaders. Personal network techniques help leaders recognize organic network cliques and bridges during implementation stages, allowing for informed support and advancement of college sustainability. From this study, sustainability practitioners may be interested in using sustainability activity frequencies for planning and sharing with other colleges, as well as using personal network techniques to develop sociograms identifying important network positions, cliques, and bridges for sustainability implementation.

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Flores, Becky. "Critical possibilities: decritique, deracination, and the D.I.S." University of Southern Queensland, Faculty of Arts, 2005. http://eprints.usq.edu.au/archive/00001424/.

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This dissertation presents the theory and practice of Decritique, a critical pedagogy for the first-year college English classroom that offers an alternative to contemporary applications of critical theory. Underscored by a philosophy of language drawn from Husserl's pure phenomenology and Derrida's deconstruction, a key characteristic of the pedagogy is delineation between re-cognition and recognition: the former actively seeking ways to re-position one's own thinking in relation to perceptions of the world; the latter endorsing existing perception. Concepts of "respect" and "tolerance" are questioned in Decritique, positing that they can operate as agents of oppression; instead, students engage in critical interaction and animated introspection that, in turn, opens the possibility of change. Concerned with the theory and practice of a reconceptualized critical pedagogy, the question at the core of Decritique is ways for students to reach a point of cognitive struggle leading to genuine discovery without the pain that can accompany criticism and critical self-reflection acting as a barrier to learning. Chapters One through Three examine what constitutes "the critical"; namely, critical thinking, critical pedagogy, critical literacy, and critical care, Chapter Four discusses a reconceptualization of these criticalities, Chapter Five examines the theory of Decritique, Chapter Six presents a three-semester pilot study comparing Decritique with a pedagogy of "caring" in both face-to-face and online learning environments, and Chapter Seven provides the study’s conclusions. Results indicate that students taught with Decritique consistently produced more writing than those taught with a "caring" approach, demonstrated greater evidence of "critical" reflection on essay revisions, engaged more animatedly in verbal and written discourse, exhibited a strong sense of critical camaraderie, particularly in the face-to-face classroom, and that essays averaged nearly five percent, or half a letter grade, higher. Retention and pass rates were higher in the Decritique classes and students were more likely to be satisfied with their learning experience. Implementation of the pedagogy on a wider, cross-institutional level is recommended in order to investigate the potential of Decritique as an alternative critical pedagogy for the first-year college English classroom, one that promotes reflective critical analysis of discourse with a commitment to the possibilities of praxis.

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Lester, Ben. "Attentional and Neural Manipulations of Visuospatial Contextual Information." Thesis, University of Oregon, 2013. http://hdl.handle.net/1794/12985.

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A critical function of the human visual system is to parse objects from the larger context of the environment, allowing for the identification of, and potential interaction with, those objects. The use of contextual information allows us to rapidly locate, identify, and interact with objects that appear in the environment. Contextual information can help specify an object's location within the environment (allocentric encoding) or with respect to the observer (egocentric encoding). Understanding how contextual information influences perceptual organization, and the neural systems that process a complex scene, is critical in understanding how contextual information assists in parsing local information from background. In the real world, relying on context is typically beneficial, as most objects occur in circumscribed environments. However, there are circumstances in which context can harm performance. In the case of visual illusions, relying on the context can bias observers' perceptions and cause significant motor errors. Studying the illusory conditions under which perceptual/motor functions are "fooled", or breakdown, can provide valuable information about how the brain computes allocentric and egocentric frames of reference. The following studies examine how attentional (Chapters II & III) manipulations of visuospatial context affect components of observers' egocentric reference frames (e.g., perceived vertical or subjective midline) and how neural manipulations (Chapter IV) can modulate observers' reliance on contextual information. In Chapter II, the role of attentional control settings on contextual processing is examined. Chapter III addresses the question of how visuospatial shifts of attention interact with an egocentric frame of reference. Finally, Chapter IV examines the functional role of superior parietal cortex in the processing of egocentric contextual information.

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杉村, 伸一郎, Shinichiro Sugimura, 峰子今川, Mineko Imagawa, 謙彰竹内, and Yoshiaki Takeuchi. "空間的視点取得課題の自己中心的反応に関する2つの理論の比較." 名古屋大学教育学部, 1995. http://hdl.handle.net/2237/3954.

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Zhang, Baiqing. "IDENTITY AND SOCIAL RELATIONS: A CASE OF CHINESE GRADUATE STUDENTS IN THE U.S." UKnowledge, 2014. https://uknowledge.uky.edu/sociology_etds/16.

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This dissertation research separates out the social relations implied in identity theory and empirically shows the interaction of identity and social relations. I conducted 60 interviews and one online survey with respondents at two public universities in two cities with distinctive sociocultural characteristics. The respondents were graduate students from mainland China pursuing their master’s or doctoral degrees in the U.S. The students’ lengths of stay in the U.S. varied, but all experienced a major life transition from China to the U.S. The qualitative interview data show that the adoption of a religious identity in the two places, defined as different social environments, impact the interaction of identity and networks. Where the community is small and homogeneous, the Chinese graduate students are quickly thrown into strong religious dyadic relationships and primary groups, and soon thereafter acquire a religious identity. Where the community is large and sparsely connected, the identity pool is large and the adoption of the religious identity becomes less constrained by dyadic relationships and primary groups. The interview data also show that within-person time spanning (the time span between prior to the respondents’ arrival in the U.S. and after the respondents’ coming to the U.S.), and between-person time spanning (the “newcomers” who have lived in the U.S. for less than one year versus the “old-timers” who have lived in the U.S. for over one year) are important in the identity network process. The transfer from China to the U.S. fosters the emergence of the Chinese ethnic identity. The Chinese network composition of the newcomers and the old-timers granted them a similar list of important identities. The quantitative findings confirm that place, time, and personal network function together to impact identity importance. Also, the classification of ties into “important people” and “time bound people” are effective predictors of identity importance. In conclusion, this dissertation research demonstrates empirically how social relations and identity impact each other. This research also provides a case study for the population – Chinese graduate students in the U.S.

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SERINO, SILVIA. "SPAZIO INTERNO ED ESTERNO: IL RUOLO DEI SISTEMI DI RIFERIMENTO SPAZIALI EGOCENTRICO E ALLOCENTRICO NELLA COGNIZIONE UMANA." Doctoral thesis, Università Cattolica del Sacro Cuore, 2015. http://hdl.handle.net/10280/6214.

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La domanda "Che cos’è lo spazio?" è sempre stata un tema centrale per la filosofia, ed è diventata di interesse anche per la psicologia cognitiva e per le neuroscienze, con una domanda cruciale strettamente legata: "Dove sono io?". Lo sforzo per collegare le risposte a queste due domande mira proprio a comprendere la complessa relazione che esiste tra lo spazio interno ed esterno, che è l'obiettivo finale di questo lavoro. L'idea è che la nostra posizione nel mondo influenzi fortemente il modo in cui codifichiamo, archiviamo e recuperiamo dalla memoria un layout spaziale. Inoltre, questo layout spaziale serve da impalcatura che vincola tutte le informazioni relative al nostro passato, presente e futuro, e tutte le esperienze legate al nostro corpo. All’interno di un approccio enattivo, si suggerisce una sincronizzazione continua (cioè, il “mental frame syncing") tra una rappresentazione allocentrica indipendente dal punto di vista allocentrica (i.e. che include solo relazioni oggetto-oggetto astratte) e una rappresentazione allocentrica dipendente dal punto di vista (i.e. che include informazioni sulla nostra direzione egocentrica attuale) possa permettere di posizionare il corpo nello “spazio memorizzato” rendendo più semplice la traduzione di questo in un “lived space” di cui si necessita per navigare, per ricordare il passato e per sentire il corpo. Sulla base di queste premesse teoriche, quattro studi sperimentali saranno presentati per studiare il ruolo del mental frame syncing come un principio di allineamento centrato sull’osservatore nei processi di codifica e di recupero delle informazioni.
The question "What is space?" has always been a central topic for philosophy, and a closely linked crucial question becomes of interest for cognitive psychology and neuroscience, that is "Where am I?" The efforts to answer these two questions are means to better understanding of the complex relation between the outer and the inner space, which is the final goal of this work. The idea is that that our bodily position in the world strongly affects the way in which we encode, store and retrieve a spatial layout. Moreover, this spatial layout serves as a scaffold, binding all the information of our past, present, future and body-related experiences. Within an enactive approach, it is suggested that this continuous synchronization (namely, the “mental frame syncing”) of an allocentric viewpoint-independent representation (i.e. including only abstract object-to-object relations) and an allocentric viewpoint-dependent representation (i.e. comprising information about our current heading) may permit to place current bodily position in the “memorized space" making easy the translation of it into a “lived space” that it is needed to navigate, remember the past and feel the body. On these theoretical premises, four experimental studies will be presented to investigate the role of mental frame syncing as an alignment principle centred on observer the processes of encoding and retrieval of information

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35

SERINO, SILVIA. "SPAZIO INTERNO ED ESTERNO: IL RUOLO DEI SISTEMI DI RIFERIMENTO SPAZIALI EGOCENTRICO E ALLOCENTRICO NELLA COGNIZIONE UMANA." Doctoral thesis, Università Cattolica del Sacro Cuore, 2015. http://hdl.handle.net/10280/6214.

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Abstract:

La domanda "Che cos’è lo spazio?" è sempre stata un tema centrale per la filosofia, ed è diventata di interesse anche per la psicologia cognitiva e per le neuroscienze, con una domanda cruciale strettamente legata: "Dove sono io?". Lo sforzo per collegare le risposte a queste due domande mira proprio a comprendere la complessa relazione che esiste tra lo spazio interno ed esterno, che è l'obiettivo finale di questo lavoro. L'idea è che la nostra posizione nel mondo influenzi fortemente il modo in cui codifichiamo, archiviamo e recuperiamo dalla memoria un layout spaziale. Inoltre, questo layout spaziale serve da impalcatura che vincola tutte le informazioni relative al nostro passato, presente e futuro, e tutte le esperienze legate al nostro corpo. All’interno di un approccio enattivo, si suggerisce una sincronizzazione continua (cioè, il “mental frame syncing") tra una rappresentazione allocentrica indipendente dal punto di vista allocentrica (i.e. che include solo relazioni oggetto-oggetto astratte) e una rappresentazione allocentrica dipendente dal punto di vista (i.e. che include informazioni sulla nostra direzione egocentrica attuale) possa permettere di posizionare il corpo nello “spazio memorizzato” rendendo più semplice la traduzione di questo in un “lived space” di cui si necessita per navigare, per ricordare il passato e per sentire il corpo. Sulla base di queste premesse teoriche, quattro studi sperimentali saranno presentati per studiare il ruolo del mental frame syncing come un principio di allineamento centrato sull’osservatore nei processi di codifica e di recupero delle informazioni.
The question "What is space?" has always been a central topic for philosophy, and a closely linked crucial question becomes of interest for cognitive psychology and neuroscience, that is "Where am I?" The efforts to answer these two questions are means to better understanding of the complex relation between the outer and the inner space, which is the final goal of this work. The idea is that that our bodily position in the world strongly affects the way in which we encode, store and retrieve a spatial layout. Moreover, this spatial layout serves as a scaffold, binding all the information of our past, present, future and body-related experiences. Within an enactive approach, it is suggested that this continuous synchronization (namely, the “mental frame syncing”) of an allocentric viewpoint-independent representation (i.e. including only abstract object-to-object relations) and an allocentric viewpoint-dependent representation (i.e. comprising information about our current heading) may permit to place current bodily position in the “memorized space" making easy the translation of it into a “lived space” that it is needed to navigate, remember the past and feel the body. On these theoretical premises, four experimental studies will be presented to investigate the role of mental frame syncing as an alignment principle centred on observer the processes of encoding and retrieval of information

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Consolo, Patricia. "Percursos de distâncias e orientações espaciais ao caminhar com visão ocluída em campo aberto." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/59/59134/tde-24112015-085611/.

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Embora a estimação de distância tenha sido extensivamente estudada, a habilidade de humanos julgarem distâncias maiores do que 30 m tem sido pouco investigada. O objetivo deste trabalho foi avaliar o desempenho de voluntários em tarefas envolvendo o julgamento de distância e de orientação espacial pelo indicativo de resposta do caminhar com a visão ocluída em distâncias de 30,00; 41,60; 57,69 e 80,00 metros, em um ambiente amplo e natural. Para tanto, trinta e cinco voluntários de ambos os sexos, com idades ente 18 e 35 anos foram divididos aleatoriamente em três tarefas experimentais. A primeira tarefa consistiu em caminhar diretamente a um alvo, com a visão ocluída, após vê-lo brevemente. A segunda tarefa consistiu em caminhar vidente até um alvo, e subsequentemente realizar um giro de 180º e retornar sozinho, com a visão ocluída, à origem do percurso. A terceira tarefa foi similar à segunda, mas com uma diferença, o participante caminhou por distâncias com a visão ocluída, pelo guiar de um condutor, e ao final da caminhada subsequentemente, girou e retornou sozinho à origem do percurso. Em todas as tarefas experimentais, a distância caminhada (em metros) e o tempo (em segundos) de cada trajetória na fase de resposta, foram coletados e registrados utilizando um receptor de Sistema de Posição Global (GPS). Após a medição do movimento, os dados extraídos do GPS foram pós-processados e as coordenadas de todas as grandezas físicas de cada sujeito foram calculadas, a saber, a distância percorrida (metros), a velocidade (metros por segundo), o desvio angular (graus), e para o caso da trajetória circular, a velocidade angular média (radianos por segundo) e o raio da trajetória circular teórica (metros). Independente da tarefa, a observação das trajetórias produzidas pelos participantes demonstrou que os desvios de direção apresentavam padrões geométricos bem definidos (reta, circular, reta-circular, reta-reta e alternada), e os padrões reta e circular foram os mais frequentes. Em todas as tarefas, a análise das distâncias caminhadas mostrou uma tendência à subconstância perceptiva por conta do valor do expoente psicofísico abaixo de 1,0. Entretanto, esta tendência foi mais acentuada na resposta de retornar a um ponto de origem após deslocamento com os participantes sob completa privação visual sem prévisualização do alvo. Nossos resultados sugerem que os padrões das trajetórias e a acurácia das distâncias produzidas dependem da amplitude da distância, do ambiente experimental onde as distâncias foram estimadas e da disponibilidade de indícios perceptuais presentes na tarefa experimental.
Although distance estimation has been extensively studied, the human ability to judge distances greater than 30.00 m has been understudied. The objective of this work was to evaluate and analyze the performance of volunteers in tasks involving the judgment of distance and spatial orientation by the response of walking with occluded vision 30.00, 41.60, 57.69 and 80.00-meter distances. For this purpose, thirty-five volunteers of both genders, aged between 18 and 35 years were invited to participate in three experimental tasks in a natural and open field. For this purpose, thirty-five volunteers aged between 18 and 35 years of both genders were invited to participate in three experimental tasks in a natural and open field. The first task consisted of walking blindfolded directly towards a target, after seeing it briefly. The second task consisted in sighted walking until the target, and after that he or she rotated 180º and returned alone with the blinded vision to the origin of the trajectory. Finally the third task was similar to the second, but with the difference that the subject walked with the occluded vision in a straight lines distances, led by the experimenter, and subsequently, to turn and returning to the origin of the route alone. In all experimental tasks, the walked distance (in meters) and the time (in seconds) of each trajectory over the distance phase were collected and registered using a Global System Position receiver (GPS). After the measurement of the movement, the data obtained from the GPS were processed, the coordinators of the movement were determined, and the physical quantities of each subject were calculated, namely the walked distance (meters), the velocity (meters per seconds), the angular deviance (degrees), and only for the circular trajectory, the mean angular velocity (radians per seconds) and the mean radius of the theoretical circular trajectory (meters). The observation of the trajectories demonstrated that the direction deviances showed well-defined geometrical patterns (straight, circular, straight-circular, straight-straight and alternate), and the straight and circular patterns were the most frequent ones. Our results suggest that both trajectory patterns and the accuracy of the participants walked distances depend on the amplitude of the distance, the experimental environment in which distances were estimated, and the availability of perceptual evidence of distance present in the experimental task.

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Cavicchia, Marina de Carvalho. "Percepção da distância egocêntrica em idosos ativos e sedentários /." Rio Claro : [s.n.], 2006. http://hdl.handle.net/11449/87413.

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Orientador: Eliane Mauerberg de Castro
Banca: Nilton Pinto Ribeiro Filho
Banca: Ricardo Kamizaki
Resumo: A percepção do espaço depende da integração das informações sensório-motoras sendo que, durante o processo de envelhecimento, essas informações podem ser alteradas, tanto em acurácia como em otimização e, então, afetar o comportamento motor. A proposta deste estudo foi verificar o status da percepção da distância egocêntrica em indivíduos idosos, usando o método experimental de triangulação. Ainda, verificar se indivíduos idosos fisicamente ativos podem ou não ter uma melhor performance do que seus pares sedentários em duas tarefas de percepção de distância. A tarefa de percepção da distância egocêntrica incluiu: 1. Apontar para os alvos continuamente enquanto caminha em uma linha reta com os olhos vendados (i.e. quatro caminhos andando com distâncias variadas foram testados) com os olhos vendados, até o final da trajetória. 2. Julgamento verbal da distância real para os alvos. Em geral, os resultados mostraram uma tendência em superestimar as distâncias curtas (i.e., 8 e 13 metros) e uma tendência em subestimar as distâncias mais longas (i.e., 20 e 30 metros). Ambos os grupos, ativos e sedentários, exibiram uma alta variabilidade na tarefa de apontar, e isso pode ser explicado pelas mudanças individuais do sistema de orientação espacial causado pelo envelhecimento. Ainda, a amplitude de movimento do braço poderia explicar o apontar não acurado para alguns alvos colocados no final do caminho percorrido. O método de triangulação não foi sensível para medir a percepção espacial destes participantes. O julgamento verbal da distância em ambos os grupos, foram igualmente acurados
Abstract: Because spatial orientation relies on integration of sensory-motor information, aging process can affect accuracy and optimization and, therefore, affect motor behavior. The purpose of this study was to verify the status of egocentric distance perception in older individuals using the triangulation experimental method. Also, to verify whether or not physically active older individuals can perform better than their sedentary peers in two egocentric distance perception tasks. The egocentric distance perception tasks included 1. pointing to targets while walking in a straight line with eyes closed (i.e., four walking paths with varied distances were tested), and 2. verbally expressing the actual distances to targets. Overall, results showed an overestimation tendency for short distances (i.e., 8 and 13 meters), and an underestimation tendency for longer distances (i.e., 20 and 30 meters). Both groups, active and sedentary, exhibited a high variability in all of the pointing task conditions. In the verbal egocentric distance perception, participants were more accurate than during the pointing task. The high variability of the pointing task can be explained by changes in individualsþ spatial orientation system caused by aging. Also, limited range of motion of the arm could explain poor pointing to some targets placed at the end of the walking pathway. The triangulation method was not sensitive to measure these participants spatial perception. The verbal judgments of distances in both groups were equally accurate
Mestre

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38

Gutierrez, Arnold. "The role of dopamine receptors in methamphetamine-induced cognitive deficits." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1521189209471948.

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39

Cavicchia, Marina de Carvalho [UNESP]. "Percepção da distância egocêntrica em idosos ativos e sedentários." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/87413.

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Made available in DSpace on 2014-06-11T19:22:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-04-10Bitstream added on 2014-06-13T20:29:14Z : No. of bitstreams: 1 cavicchia_mc_me_rcla.pdf: 485720 bytes, checksum: c910b38b7806cbea37a47eb57d7a5468 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A percepção do espaço depende da integração das informações sensório-motoras sendo que, durante o processo de envelhecimento, essas informações podem ser alteradas, tanto em acurácia como em otimização e, então, afetar o comportamento motor. A proposta deste estudo foi verificar o status da percepção da distância egocêntrica em indivíduos idosos, usando o método experimental de triangulação. Ainda, verificar se indivíduos idosos fisicamente ativos podem ou não ter uma melhor performance do que seus pares sedentários em duas tarefas de percepção de distância. A tarefa de percepção da distância egocêntrica incluiu: 1. Apontar para os alvos continuamente enquanto caminha em uma linha reta com os olhos vendados (i.e. quatro caminhos andando com distâncias variadas foram testados) com os olhos vendados, até o final da trajetória. 2. Julgamento verbal da distância real para os alvos. Em geral, os resultados mostraram uma tendência em superestimar as distâncias curtas (i.e., 8 e 13 metros) e uma tendência em subestimar as distâncias mais longas (i.e., 20 e 30 metros). Ambos os grupos, ativos e sedentários, exibiram uma alta variabilidade na tarefa de apontar, e isso pode ser explicado pelas mudanças individuais do sistema de orientação espacial causado pelo envelhecimento. Ainda, a amplitude de movimento do braço poderia explicar o apontar não acurado para alguns alvos colocados no final do caminho percorrido. O método de triangulação não foi sensível para medir a percepção espacial destes participantes. O julgamento verbal da distância em ambos os grupos, foram igualmente acurados.
Because spatial orientation relies on integration of sensory-motor information, aging process can affect accuracy and optimization and, therefore, affect motor behavior. The purpose of this study was to verify the status of egocentric distance perception in older individuals using the triangulation experimental method. Also, to verify whether or not physically active older individuals can perform better than their sedentary peers in two egocentric distance perception tasks. The egocentric distance perception tasks included 1. pointing to targets while walking in a straight line with eyes closed (i.e., four walking paths with varied distances were tested), and 2. verbally expressing the actual distances to targets. Overall, results showed an overestimation tendency for short distances (i.e., 8 and 13 meters), and an underestimation tendency for longer distances (i.e., 20 and 30 meters). Both groups, active and sedentary, exhibited a high variability in all of the pointing task conditions. In the verbal egocentric distance perception, participants were more accurate than during the pointing task. The high variability of the pointing task can be explained by changes in individualsþ spatial orientation system caused by aging. Also, limited range of motion of the arm could explain poor pointing to some targets placed at the end of the walking pathway. The triangulation method was not sensitive to measure these participants spatial perception. The verbal judgments of distances in both groups were equally accurate.

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Ta, Huynh Duy Nguyen. "The roles of allocentric representations in autonomous local navigation." Diss., Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53489.

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In this thesis, I study the computational advantages of the allocentric represen- tation as compared to the egocentric representation for autonomous local navigation. Whereas in the allocentric framework, all variables of interest are represented with respect to a coordinate frame attached to an object in the scene, in the egocentric one, they are always represented with respect to the robot frame at each time step. In contrast with well-known results in the Simultaneous Localization and Mapping literature, I show that the amounts of nonlinearity of these two representations, where poses are elements of Lie-group manifolds, do not affect the accuracy of Gaussian- based filtering methods for perception at both the feature level and the object level. Furthermore, although these two representations are equivalent at the object level, the allocentric filtering framework is better than the egocentric one at the feature level due to its advantages in the marginalization process. Moreover, I show that the object- centric perspective, inspired by the allocentric representation, enables novel linear- time filtering algorithms, which significantly outperform state-of-the-art feature-based filtering methods with a small trade-off in accuracy due to a low-rank approximation. Finally, I show that the allocentric representation is also better than the egocentric representation in Model Predictive Control for local trajectory planning and obstacle avoidance tasks.

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King, Owen Christopher. "Three Kinds of Goodness for a Person." The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1461257876.

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Brett, Frances Madeleine. "Effect of spatial visual cue proximity and thalamic lesions on performance of rats on a cheeseboard maze task." Thesis, University of Canterbury. Psychology, 2011. http://hdl.handle.net/10092/5803.

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Episodic memory is processed by the extended hippocampal system, and pathology or injury to individual components of this system can result in deficits in spatial learning and memory (Aggleton & Brown, 1999). Extensive research regarding spatial memory has been carried out on the anterior thalamic nuclei, a component of the extended hippocampal system, but the contribution of the laterodorsal thalamic nuclei, an adjacent structure with similar neural connections, is less clear. The purpose of the present study was to compare the effects of selective anterior thalamic nuclei lesions (AT) with selective laterodorsal thalamic nuclei lesions (LD) in a novel land-based spatial reference memory task. This assessed the use of proximal and distal visual cues on the propensity to use allocentric or egocentric navigation strategies to locate a specific place in space, as well as the temporal evolution of these navigation strategies. AT lesion impairments were observed in the acquisition trials in both proximal and distal cue conditions. LD lesion rats were unimpaired in the acquisition trials in both visual cue conditions. Across the probe trials, lesion effects were not observed when tested for general navigation, egocentric or allocentric strategies, and there was no clear improvement in performance over the four weeks of probe trials. However, performance was consistently poorer for all groups when proximal cues facilitated navigation compared to distal cues. Performance differences related to cue proximity may reflect the influence of motion parallax, the perceived displacement rate of visual cues. The absence of lesion effects across probes were thought to be due to the preferential use of cued navigation, which was reliant on a single salient beacon, and the lack of integration between cued and place navigation, which was reliant on the formation of a spatial representation.

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Bettadapura, Vinay Kumar. "Leveraging contextual cues for dynamic scene understanding." Diss., Georgia Institute of Technology, 2016. http://hdl.handle.net/1853/54834.

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Environments with people are complex, with many activities and events that need to be represented and explained. The goal of scene understanding is to either determine what objects and people are doing in such complex and dynamic environments, or to know the overall happenings, such as the highlights of the scene. The context within which the activities and events unfold provides key insights that cannot be derived by studying the activities and events alone. \emph{In this thesis, we show that this rich contextual information can be successfully leveraged, along with the video data, to support dynamic scene understanding}. We categorize and study four different types of contextual cues: (1) spatio-temporal context, (2) egocentric context, (3) geographic context, and (4) environmental context, and show that they improve dynamic scene understanding tasks across several different application domains. We start by presenting data-driven techniques to enrich spatio-temporal context by augmenting Bag-of-Words models with temporal, local and global causality information and show that this improves activity recognition, anomaly detection and scene assessment from videos. Next, we leverage the egocentric context derived from sensor data captured from first-person point-of-view devices to perform field-of-view localization in order to understand the user's focus of attention. We demonstrate single and multi-user field-of-view localization in both indoor and outdoor environments with applications in augmented reality, event understanding and studying social interactions. Next, we look at how geographic context can be leveraged to make challenging ``in-the-wild" object recognition tasks more tractable using the problem of food recognition in restaurants as a case-study. Finally, we study the environmental context obtained from dynamic scenes such as sporting events, which take place in responsive environments such as stadiums and gymnasiums, and show that it can be successfully used to address the challenging task of automatically generating basketball highlights. We perform comprehensive user-studies on 25 full-length NCAA games and demonstrate the effectiveness of environmental context in producing highlights that are comparable to the highlights produced by ESPN.

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Corbin, Sierra Fontaine. "Keeping Your Friends Close: Perceived Distance as a Function of Psychological Closeness." University of Dayton / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1497502217239512.

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On-At, Sirinya. "Temporalité et réseaux sociaux : prise en compte de l'évolution dans la construction du profil utilisateur." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30071/document.

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Pour pouvoir restituer des informations qui correspondent aux besoins de l'utilisateur, les mécanismes d'adaptation doivent disposer de métadonnées sur celui-ci telles que ses caractéristiques personnelles, ses préférences générales, ses centres d'intérêt. De ce fait, le profil utilisateur construit à partir de celles-ci devient central dans tout système basé sur la personnalisation. Dans cette thèse, nous nous focalisons sur l'approche qui consiste à s'appuyer sur le réseau social de l'utilisateur pour enrichir le profil de cet utilisateur, les métadonnées explicites étant complétées par les informations issues de notre processus d'analyse. Nous appelons les techniques ou processus associés à cette approche " profilage social ". Le terme " profil social " désigne un profil construit à l'aide du réseau social de l'utilisateur. Un profil social contient les métadonnées traduisant les intérêts de l'utilisateur extraits à partir des informations partagées par les individus de son réseau social. Les intérêts de l'utilisateur évoluant au fil du temps dans la vie réelle, il en est de même pour ceux extraits depuis son réseau social : pertinents à un moment donné, ils peuvent ne plus être significatifs ultérieurement. Partant de ce constat, les principales informations que nous souhaitons étudier pour détecter un changement de centres d'intérêt ne sont pas ciblées sur l'utilisateur lui-même mais sur les éléments de son réseau social (liens entre les membres, informations qui circulent entre eux) : l'évolution du profil social de l'utilisateur est donc liée à l'évolution de son réseau social. Nous proposons une démarche générique de profilage social efficace permettant de construire un profil social représentatif de l'utilisateur prenant en compte différents types de réseaux ainsi que leurs caractéristiques évolutives. Pour prendre en compte l'évolution des intérêts dans le profil social, nous avons proposé d'améliorer l'efficacité des processus de construction du profil social existants en intégrant la prise en compte de l'évolution du réseau social de l'utilisateur. Nous proposons d'intégrer un facteur temporel dans ces processus (approche basée sur des individus et approche basée sur les communautés). La solution permet de privilégier les intérêts provenant d'informations significatives et à jour. Il s'agit donc d'intégrer une mesure temporelle dans l'étape d'extraction et pondération des intérêts. Cette mesure est calculée d'une part, à partir de la pertinence temporelle des informations utilisées pour extraire cet intérêt et d'autre part, à partir de la pertinence temporelle de l'individu qui partage ces informations. Nous mettons en œuvre la méthode proposée au travers d'expérimentations dans deux réseaux sociaux différents : DBLP, un réseau de publications scientifiques et Twitter, un réseau de micro-blogs. Les résultats de ces expérimentations nous ont permis de montrer l'efficacité de la méthode temporelle proposée par rapport aux processus de construction du profil social qui ne prennent pas en compte des critères temporels. En étudiant les résultats en fonction des techniques de pondération des intérêts ou fonctions temporelles utilisées, nous constatons que la fonction temporelle et la technique utilisées donnant les meilleurs résultats varient selon l'approche de construction du profil social choisie, selon la taille et la densité du réseau étudié mais aussi selon sur le type de réseau. La problématique abordée dans cette thèse est relativement nouvelle dans le contexte des systèmes de personnalisation de l'information et ouvre de nombreuses perspectives : évaluation du profil social dans un système de recommandation par exemple, application de la méthode proposée dans d'autres types de réseaux sociaux, application de techniques de mise à jour du profil, conception d'une plateforme de construction du profil social selon les caractéristiques du réseau
User profiling is essential for personalization systems (e.g. personalized information retrieval systems, recommendation systems) to identify user information (preference, interests...), in order to propose relevant content based on his/her specific needs and requirements. Many works have shown that user's social neighbors can be a meaningful source to infer his/her interests. Besides, sociology works have shown that the user is better described by people around him/her, especially the people that are directly connected to him/her (his egocentric network). In this work, the term "social profiling" is considered as the interest extraction approach that consists in extracting user interests from information of his/her social neighbors. The user's profile built within this approach is called "social profile". As user behaviors evolve over time, it is necessary to take into consideration the evolution of user interests in user profiling process. In the case of social profile, user interests are extracted from the information shared by his/her social neighbors. Hence, the evolution of extracted interests is related to the evolution of information shared on user social network and to the evolution of relationships between the user and his/her social neighbors. This issue becomes particularly important in the Online Social Networks (OSNs) context where user behavior changes quickly. For a user, the relationships and information in his/her social network can evolve and become obsolete for him/her overtime. Two users creating a relationship are not required to know each other in real life. Thus, the relationship persistence is not always maintained in this case. Social events or viral marketing (buzz) are also factors that enhance online social content sharing. In this work, we propose a generic approach that considers the evolution in user's social network in the social profiling process and can be applied in different types of social network. To handle this, we propose to apply a time-aware method into existing social profile building process (individual based and community based approaches). This strategy aims at weighting user's interests in the social profile based on their temporal score. The temporal score of an interest is computed by combining the temporal score of information used to extract the interests (computed by considering their freshness) with the temporal of individuals who share the information in the network (computed by considering the freshness of the interaction with the user). The technique and temporal function used to compute the temporal score are customizable. Thus, we can find out the most appropriate technique or temporal function depending on the types or characteristics of the adopted social network. The experiments conducted on DBLP and Twitter showed that the so-called time-aware social profiling process applying our proposed time-aware method outperforms the existing time-agnostic social profiling process. We also found that the most appropriate technique, temporal function and social profiling approach vary depending on the network characteristics (size, density) and to the social network type. Our approach opens many opportunities for future studies in social information filtering and many application domains as well as on the Web (e.g. evolution of social profile in personalization of search engines, recommender systems in e-commerce,). Our long-term perspective consists in the proposal of a generic platform that extracts the information and builds the user social profile based on the type and the specific characteristics of the underlying social network. Such a platform would be parameterized by the characteristics of the targeted social network using a machine learning approach

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46

BALLESTIN, GIORGIO. "A Registration Framework for the Comparison of Video and Optical See-Through Devices in Interactive Augmented Reality." Doctoral thesis, Università degli studi di Genova, 2021. http://hdl.handle.net/11567/1046985.

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Augmented Reality (AR) is a technology that has been growing in interest in the past decade. Many factors are currently hindering its distribution to the general public. The heavy processing requirements, hardware limitations, and the need for an easy to use portable/wearable device are still problems to be addressed. The AR field is currently split between the use of widespread devices (smartphones) for easily deployable applications, and the use of high-end Head Mounted Displays (HMD), which are generally very expensive, and often require a cumbersome tethered high-end computer rig to the side. In the next evolution of Wearable devices and Internet of Things, Augmented Reality can play a key role in the human-computer interaction field. The potential of having access to computational capabilities embedded in a simple pair of glasses is huge, from professional applications (in medicine, industry, design) to every-day's life. Augmented Reality problematics are strictly related to the way the registration and visualization are performed. During registration, a model of the environment is obtained through several sensors (often with cameras). The obtained model is then used to digitally augment the image with additional images before conveying the merged view to the user. This process, however, is still far from being perfect. The environmental registration is currently a computationally complex task, which leads to very simplified models, that often hinder the development space. Different visualization techniques also have a different impact on the users, due to the introduction of parallaxes and latencies, which cause several artifacts and perception issues. To this aim, we developed a registration framework that can be used to develop augmented reality environments, having all the real (including the users) and virtual elements co-localized and registered in a common reference frame. Specifically, several devices are calibrated and aligned in a common reference frame, and measurements are captured with an external independent common measurement system. The proposed framework is based on methodologies that can be used for any device. We then used the proposed framework to create AR scenarios, to assess the optical and perceptual differences of different types of AR HMDs and their impact on the interactivity. The methodology involves the design of several experimental sessions under rigorous, repeatable conditions, and the subsequent evaluation of performances. Residual errors, user experiences end performances were evaluated considering both quantitative and qualitative metrics derived from the collection and the analysis of heterogeneous, unbiased data, and self-assessment questionnaires. Our results show that depth perception appears to be compressed when using several AR HMDs, potentially hindering the interaction with AR environments. The effect is particularly prominent when fewer cues and feedbacks are provided. If the users are able to perform a visual alignment between the real and virtual geometries, however, an effective interaction can be achieved, even if the overlap is not perfect.

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47

Markowski, Kelly Lorraine. "Identity, Networks, and Mental Health: The Relationship between Structures and Meaning on Distress and Subjective Wellbeing." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1555942428443257.

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48

Harvey, Aimee Marie. "Adolescent egocentrism and psychosis." Thesis, University of Birmingham, 2013. http://etheses.bham.ac.uk//id/eprint/3931/.

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Research has noted the onset of psychosis during adolescence and the influence of childhood adversity on the risk for psychosis. Prior social and self-construction difficulties contributory to psychosis and theorised to impinge upon adolescent development have also been highlighted. However, despite these links little empirical research has investigated this. This thesis aims to investigate the contributions of disruptions and exaggerations to adolescent egocentrism suggested by Harrop and Trower (2001). This thesis investigated the relationship between psychosis and adolescent egocentrism in healthy adolescents, young people at high risk of psychosis and those with a first episode of psychosis. These relationships were tracked across the adolescent period and finally examined in clinical samples. It was found that a rise in psychotic-like experiences in mid-adolescence was linked to a rise in egocentric thinking suggesting that adolescent egocentrism contributes to psychotic-like experiences in healthy adolescents. At the clinical psychosis level, adolescent egocentrism was not contributory; however findings suggested that early emotional trauma and insecure attachment were moderated by adolescent egocentrism difficulties influencing the persistence of psychotic-like experiences into psychosis. These findings support the critical importance of adolescent development and developmental risk factors within the genesis of psychosis.

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49

Shakeri, Heman. "Complex network analysis using modulus of families of walks." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35525.

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Doctor of Philosophy
Department of Electrical and Computer Engineering
Pietro Poggi-Corradini
Caterina M. Scoglio
The modulus of a family of walks quanti es the richness of the family by favoring having many short walks over a few longer ones. In this dissertation, we investigate various families of walks to study new measures for quantifying network properties using modulus. The proposed new measures are compared to other known quantities. Our proposed method is based on walks on a network, and therefore will work in great generality. For instance, the networks we consider can be directed, multi-edged, weighted, and even contain disconnected parts. We study the popular centrality measure known in some circles as information centrality, also known as e ective conductance centrality. After reinterpreting this measure in terms of modulus of families of walks, we introduce a modi cation called shell modulus centrality, that relies on the egocentric structure of the graph. Ego networks are networks formed around egos with a speci c order of neighborhoods. We then propose e cient analytical and approximate methods for computing these measures on both directed and undirected networks. Finally, we describe a simple method inspired by shell modulus centrality, called general degree, which improves simple degree centrality and could prove to be a useful tool for practitioners in the applied sciences. General degree is useful for detecting the best set of nodes for immunization. We also study the structure of loops in networks using the notion of modulus of loop families. We introduce a new measure of network clustering by quantifying the richness of families of (simple) loops. Modulus tries to minimize the expected overlap among loops by spreading the expected link-usage optimally. We propose weighting networks using these expected link-usages to improve classical community detection algorithms. We show that the proposed method enhances the performance of certain algorithms, such as spectral partitioning and modularity maximization heuristics, on standard benchmarks. Computing loop modulus bene ts from e cient algorithms for nding shortest loops, thus we propose a deterministic combinatorial algorithm that nds a shortest cycle in graphs. The proposed algorithm reduces the worst case time complexity of the existing combinatorial algorithms to O(nm) or O(hkin2 log n) while visiting at most m - n + 1 cycles (size of cycle basis). For most empirical networks with average degree in O(n1􀀀 ) our algorithm is subcubic.

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Priot, Anne-Emmanuelle. "Composantes de l’adaptation à une altération des distances apparentes par modification de la demande en vergence." Thesis, Lyon 1, 2010. http://www.theses.fr/2010LYO10336/document.

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De nombreuses situations modifient les coordinations sensorimotrices (e.g., croissance, pathologie, interfaces optiques ou mécaniques). Le système nerveux doit alors s’adapter afin de préserver la précision de ses interactions avec l’environnement. Si l’adaptation visuomotrice à une altération de la direction visuelle par prismes latéraux a été largement étudiée, les mécanismes de l’adaptation visuomotrice à une altération des distances apparentes sont en revanche peu connus. Ce travail regroupe une série d’études de psychophysique explorant les mécanismes de l’adaptation visuomotrice à une altération des distances apparentes, lors d’une exposition à court terme dans l’espace de préhension. L’altération des distances apparentes a été réalisée par modification de la vergence à l’aide de prismes à bases externes. La manipulation des retours visuels a permis de mettre en évidence trois niveaux d’adaptation. Le premier niveau concerne la modification des distances perçues liée à l’augmentation de la vergence tonique. Cette modification résulte de la potentiation musculaire extra-oculaire (EMP) induite par une convergence soutenue. Le second niveau implique la recalibration du signal altéré de distance dérivé de la vergence par les signaux proprioceptivo-moteurs du membre supérieur exposé. Le troisième niveau résulte d’une réorganisation des commandes motrices du membre exposé. Aucune adaptation proprioceptive du membre exposé n’a été retrouvée. La nature des composantes adaptatives à une altération des distances apparentes diffère de celle classiquement décrite pour l’altération de la direction visuelle impliquant essentiellement des composantes proprioceptive et motrice. La contribution des composantes adaptatives sensorielles est déterminée par la précision respective de la localisation spatiale fondée sur la vision et sur la proprioception, qui diffère en latéral et en profondeur. D’autre part, les aspects géométriques de la perception des distances fondée sur la vergence ont été explorés par comparaison de l’adaptation visuelle aux prismes à bases externes (augmentant la demande en vergence d’un angle constant pour toutes les distances de fixation) et au téléstéréoscope (multipliant la demande en vergence pour toutes les distances de fixation). Quel que soit le dispositif optique utilisé, l’adaptation visuelle a consisté en un effet consécutif ne dépendant pas de la distance d’observation, contrairement aux résultats prédits sur la base du signal de vergence
There are numerous situations in which sensorimotor coordination is altered (e.g., growth, pathology, optical or mechanical interfaces). In such situations, the nervous system must adapt so that the organism continues to interact successfully with the environment. While visuomotor adaptation to visual direction alteration by lateral prisms has been widely studied, the mechanisms underlying visuomotor adaptation to alteration of apparent distance remain poorly known. We performed a series of psychophysical studies to explore the various components of adaptation to alteration of apparent distance. Base-out prisms were used to alter apparent distance by modifying vergence demand. By manipulating visual feedback, we were able to demonstrate three adaptation levels. The first level corresponds to changes in perceived distance related to tonic vergence. These changes result from eye muscle potentiation (EMP) induced by sustained vergence. The second level involves a recalibration of the altered distance signal derived from vergence by limb proprioceptive-motor signals. The third level results from a reorganization of motor commands of the upper limb used. No limb proprioceptive component was identified. The nature of adaptive components to apparent distance alteration differs from that described for visual direction alteration, which involves essentially proprioceptive and motor components. This difference can be attributed to differences in accuracy between proprioception and vision for localization in depth or in lateral directions. The geometrical aspects of distance perception based on vergence were also explored by comparing visual adaptation to base-out prisms (introducing an offset in vergence demand) and to a telestereoscope (multiplying vergence demand for all fixation distances). Regardless of which optic device was used, the recalibration of the relationship between the vergence signal and perceived distance consisted in a constant bias over distances

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Dissertations / Theses on the topic 'Egocentric'

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