314 research outputs found

    Low vision, stimulus encoding and information processing: a characterization of performance of partially sighted users on computer-based tasks

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    This study focuses on the characterization of partially sighted users\u27 performance within a graphical user interface environment. Participants, ranging in visual abilities from fully sighted (FSU) with no visual impairments to partially sighted (PSU) with limited visual abilities, participated in computer-based search and select tasks. It is shown that visual search strategies employed by both PSU and FSU within a graphical user interface can be described by Steinberg\u27s (1969) Additive Factor Model. In addition, selection strategies, measured by mouse movement times, are linearly related and highly correlated to the Index of Difficulty as explained by Fitts\u27 Law. This is the first study of its kind that links the physiology of partial vision to behaviors and strategies exhibited during psychomotor task performance. These results can enable system interface designers to effectively design and accommodate the wide range of visual capabilities of today\u27s growing population of computer users

    A Formal Approach to Computer Aided 2D Graphical Design for Blind People

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    The growth of computer aided drawing systems for blind people (CADB) has long been recognised and has increased in interest within the assistive technology research area. The representation of pictorial data by blind and visually impaired (BVI) people has recently gathered momentum with research and development; however, a survey of published literature on CADB reveals that only marginal research has been focused on the use of a formal approach for on screen spatial orientation, creation and reuse of graphics artefacts. To realise the full potential of CADB, such systems should possess attributes of usability, spatial navigation and shape creation features without which blind users drawing activities are less likely to be achieved. As a result of this, usable, effective and self-reliant CADB have arisen from new assistive Technology (AT) research. This thesis contributes a novel, abstract, formal approach that facilitates BVI users to navigate on the screen, create computer graphics/diagrams using 2D shapes and user-defined images. Moreover, the research addresses the specific issues involved with user language by formulating specific rules that make BVI user interaction with the drawing effective and easier. The formal approach proposed here is descriptive and it is specified at a level of abstraction above the concrete level of system technologies. The proposed approach is unique in problem modelling and syntheses of an abstract computer-based graphics/drawings using a formal set of user interaction commands. This technology has been applied to enable blind users to independently construct drawings to satisfy their specific needs without recourse to a specific technology and without the intervention of support workers. The specification aims to be the foundation for a system scope, investigation guidelines and user-initiated command-driven interaction. Such an approach will allow system designers and developers to proceed with greater conceptual clarity than it is possible with current technologies that is built on concrete system-driven prototypes. In addition to the scope of the research the proposed model has been verified by various types of blind users who have independently constructed drawings to satisfy their specific needs without the intervention of support workers. The effectiveness and usability of the proposed approach has been compared against conventional non-command driven drawing systems by different types of blind users. The results confirm that the abstract formal approach proposed here using command-driven means in the context of CADB enables greater comprehension by BVI users. The innovation can be used for both educational and training purposes. The research, thereby sustaining the claim that the abstract formal approach taken allows for the greater comprehension of the command-driven means in the context of CADB, and how the specification aid the design of such a system

    Creating mobile gesture-based interaction design patterns for older adults : a study of tap and swipe gestures with portuguese seniors

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    Tese de mestrado. Multimédia. Faculdade de Engenharia. Universidade do Porto. 201

    Exploring multimedia and interactive technologies

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    The goal of multimedia design strategies and innovation is to produce meaningful learning environments that relate to and build upon what the learner already knows and what the learner seeks. The multimedia tools used to achieve knowledge transfer should activate recall or prior knowledge and help the learner alter and encode new structures. Traditionally, multimedia has been localized to specific delivery systems and demographics based on the government, industry, or academic concentration. The presenter will explore the introduction of immersive telecommunications technologies, constructivist learning methodologies, and adult learning models to standardize networking and multimedia-based services and products capable of adapting to wired and wireless environments, different devices and conditions on a global scale

    Sviluppo e sperimentazione di un ambiente interattivo per il potenziamento della coordinazione visuo-motoria in bambini con ipovisione grave

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    In una società moderna basata sull'abilità del vedere, la vista gioca un ruolo critico in ogni momento e fase della vita di una persona. Purtroppo, non tutti "vedono" allo stesso modo. Con un team multidisciplinare che comprendeva ingegneri informatici e terapisti della Fondazione Robert Hollman, sono stati progettati e sviluppati una serie di mini giochi digitali esplicitamente rivolti a bambini con problemi di vista e che mirano a migliorare le loro abilità cognitive e/o motorio-sensoriali. Questa tesi analizza i requisiti dei giochi che hanno necessitato di un'attenta e dettagliata progettazione che tenesse conto delle caratteristiche e dei bisogni degli operatori (terapisti) e dei giocatori. Descrive anche i dettagli sull'implementazione di tre giochi. Questi si basano su un large-scale interactive environment e vengono giocati proiettando il campo sul pavimento. Sopra quest'area viene posto un sistema di motion capture che permette di tracciare la posizione dei bambini. I movimenti dei giocatori all'interno del campo vengono usati per farli interagire con gli elementi del gioco, producendo output visivi e uditivi adeguati. Infine, vengono discussi l'usabilità e la funzionalità del sistema tramite l'analisi dei dati raccolti durante uno studio pilota. Quattro terapisti e undici bambini sono stati coinvolti facendo utilizzare loro il sistema in un ambiente appositamente predisposto. I risultati hanno permesso al team di migliorare il prodotto e di definire una serie di linee guida utili a terapisti, progettisti e sviluppatori.In a modern society based on the ability to see, vision plays a critical role in every moment and stage of a person's life. Unfortunately, not everyone "sees" in the same way. With a multidisciplinary team including computer engineers and therapists from the Robert Hollman Foundation, a series of digital mini-games, explicitly aimed at children with visual impairment, were designed and developed with the aim of improving their cognitive and/or motor-sensory skills. This thesis analyses the design requirements of the games, which needed a careful and detailed design that took into account the characteristics and needs of the operators (therapists) and players. It also details the implementation of three games based on a large-scale interactive environment that are played by projecting the field onto the floor. Above this area a motion capture system is placed to track the position of the children. The players' movements within the field are used to make them interact with the game elements, producing appropriate visual and auditory outputs. Finally, the usability and functionality of the system are discussed through the analysis of data collected during a pilot study. Four therapists and eleven children has been involved making them use the system in a specially designed environment. The results allowed the team to improve the final product and to define a set of guidelines useful for designers, developers, and therapists

    Multisensory Perception and Learning: Linking Pedagogy, Psychophysics, and Human–Computer Interaction

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    In this review, we discuss how specific sensory channels can mediate the learning of properties of the environment. In recent years, schools have increasingly been using multisensory technology for teaching. However, it still needs to be sufficiently grounded in neuroscientific and pedagogical evidence. Researchers have recently renewed understanding around the role of communication between sensory modalities during development. In the current review, we outline four principles that will aid technological development based on theoretical models of multisensory development and embodiment to foster in-depth, perceptual, and conceptual learning of mathematics. We also discuss how a multidisciplinary approach offers a unique contribution to development of new practical solutions for learning in school. Scientists, engineers, and pedagogical experts offer their interdisciplinary points of view on this topic. At the end of the review, we present our results, showing that one can use multiple sensory inputs and sensorimotor associations in multisensory technology to improve the discrimination of angles, but also possibly for educational purposes. Finally, we present an application, the ‘RobotAngle’ developed for primary (i.e., elementary) school children, which uses sounds and body movements to learn about angles

    Users' performance of accessible sound-only computer games

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    This work is conducted at two levels to meet the requirements of this research. The first objective is to develop a better understanding of how to design better sound-only games for a wide range of users. A new theoretical framework has been crafted to achieve this objective (Human Understanding Theory of Novel Games with Simplex, or the HUNGS theory). Such a theory aims to capture the current consensus about user requirements (as far as it is possible to do so) whilst understanding the principles and practices of interactive systems, namely the design of accessible sound-only games. The second objective is to understand better the psychology of intended users of such games. The importance of the present work is to test psychological concepts in the very different and very popular context of computer games. Implications found for users at work or working on serious tasks may not generalize to game players. To achieve the second requirement, a number of existing games were explored before a new game was designed (namely the Totally Lost game), using a range of methods. The Totally Lost game and different versions of the same game have been designed and evaluated based on user experiences

    Visual Impairment and Blindness

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    Blindness and vision impairment affect at least 2.2 billion people worldwide with most individuals having a preventable vision impairment. The majority of people with vision impairment are older than 50 years, however, vision loss can affect people of all ages. Reduced eyesight can have major and long-lasting effects on all aspects of life, including daily personal activities, interacting with the community, school and work opportunities, and the ability to access public services. This book provides an overview of the effects of blindness and visual impairment in the context of the most common causes of blindness in older adults as well as children, including retinal disorders, cataracts, glaucoma, and macular or corneal degeneration

    Collaborative adaptive accessibility and human capabilities

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    This thesis discusses the challenges and opportunities facing the field of accessibility, particularly as computing becomes ubiquitous. It is argued that a new approach is needed that centres around adaptations (specific, atomic changes) to user interfaces and content in order to improve their accessibility for a wider range of people than targeted by present Assistive Technologies (ATs). Further, the approach must take into consideration the capabilities of people at the human level and facilitate collaboration, in planned and ad-hoc environments. There are two main areas of focus: (1) helping people experiencing minor-to-moderate, transient and potentially-overlapping impairments, as may be brought about by the ageing process and (2) supporting collaboration between people by reasoning about the consequences, from different users perspectives, of the adaptations they may require. A theoretical basis for describing these problems and a reasoning process for the semi-automatic application of adaptations is developed. Impairments caused by the environment in which a device is being used are considered. Adaptations are drawn from other research and industry artefacts. Mechanical testing is carried out on key areas of the reasoning process, demonstrating fitness for purpose. Several fundamental techniques to extend the reasoning process in order to take temporal factors (such as fluctuating user and device capabilities) into account are broadly described. These are proposed to be feasible, though inherently bring compromises (which are defined) in interaction stability and the needs of different actors (user, device, target level of accessibility). This technical work forms the basis of the contribution of one work-package of the Sustaining ICT use to promote autonomy (Sus-IT) project, under the New Dynamics of Ageing (NDA) programme of research in the UK. Test designs for larger-scale assessment of the system with real-world participants are given. The wider Sus-IT project provides social motivations and informed design decisions for this work and is carrying out longitudinal acceptance testing of the processes developed here
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