13 research outputs found

    Cognitive map formation through tactile map navigation in visually impaired and sighted persons

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    The human brain can form cognitive maps of a spatial environment, which can support wayfinding. In this study, we investigated cognitive map formation of an environment presented in the tactile modality, in visually impaired and sighted persons. In addition, we assessed the acquisition of route and survey knowledge. Ten persons with a visual impairment (PVIs) and ten sighted control participants learned a tactile map of a city-like environment. The map included five marked locations associated with different items. Participants subsequently estimated distances between item pairs, performed a direction pointing task, reproduced routes between items and recalled item locations. In addition, we conducted questionnaires to assess general navigational abilities and the use of route or survey strategies. Overall, participants in both groups performed well on the spatial tasks. Our results did not show differences in performance between PVIs and sighted persons, indicating that both groups formed an equally accurate cognitive map. Furthermore, we found that the groups generally used similar navigational strategies, which correlated with performance on some of the tasks, and acquired similar and accurate route and survey knowledge. We therefore suggest that PVIs are able to employ a route as well as survey strategy if they have the opportunity to access route-like as well as map-like information such as on a tactile map

    Schematisation in Hard-copy Tactile Orientation Maps

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    This dissertation investigates schematisation of computer-generated tactile orientation maps that support mediation of spatial knowledge of unknown urban environments. Computergenerated tactile orientation maps are designed to provide the blind with an overall impression of their surroundings. Their details are displayed by means of elevated features that are created by embossers and can be distinguished by touch. The initial observation of this dissertation states that only very little information is actually transported through tactile maps owing to the coarse resolution of tactual senses and the cognitive effort involved in the serial exploration of tactile maps. However, the differences between computer-generated, embossed tactile maps and manufactured, deep-drawn tactile maps are significant. Therefore the possibilities and confines of communicating information through tactile maps produced with embossers is a primary area of research. This dissertation has been able to demonstrate that the quality of embossed prints is an almost equal alternative to traditionally manufactured deep-drawn maps. Their great advantage is fast and individual production and (apart from the initial procurement costs for the printer)low price, accessibility and easy understanding without the need of prior time-consuming training. Simplification of tactile maps is essential, even more so than in other maps. It can be achieved by selecting a limited number from all map elements available. Qualitative simplification through schematisation may present an additional option to simplification through quantitative selection. In this context schematisation is understood as cognitively motivated simplification of geometry and synchronised maintenance of topology. Rather than further reducing the number of displayed objects, the investigation concentrates on how the presentation of different forms of streets (natural vs. straightened) and junctions (natural vs. prototypical) affects the transfer of knowledge. In a second area of research, a thesis establishes that qualitative simplification of tactile orientation maps through schematisation can enhance their usability and make them easier to understand than maps that have not been schematised. The dissertation shows that simplifying street forms and limiting them to prototypical junctions does not only accelerate map exploration but also has a beneficial influence on retention performance. The majority of participants that took part in the investigation selected a combination of both as their preferred display option. Tactile maps that have to be tediously explored through touch, uncovering every detail, complicate attaining a first impression or an overall perception. A third area of research is examined, establishing which means could facilitate map readersâ options to discover certain objects on the map quickly and without possessing a complete overview. Three types of aids are examined: guiding lines leading from the frame of the map to the object, position indicators represented by position markers at the frame of the map and coordinate specifications found within a grid on the map. The dissertation shows that all three varieties can be realised by embossers. Although a guiding line proves to be fast in size A4 tactile maps containing only one target object and few distracting objects, it also impedes further exploration of the map (similar to the grid). In the following, advantages and drawbacks of the various aids in this and other applications are discussed. In conclusion the dissertation elaborates on the linking points of all three examinations. They connect and it is argued that cognitively motivated simplification should be a principle of construction for embossed tactile orientation maps in order to support their use and comprehension. A summary establishes the recommendations that result from this dissertation regarding construction of tactile orientation maps considering the limitations through embosser constraints. Then I deliberate how to adapt schematisation of other maps contingent to intended function, previous knowledge of the map reader, and the relation between the time in which knowledge is acquired and the time it is employed. Closing the dissertation, I provide an insight into its confines and deductions and finish with a prospective view to possible transfers of the findings to other applications, e.g. multimedia or interactive maps on pin-matrix displays and devices

    Interactive maps for visually impaired people : design, usability and spatial cognition

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    Connaître la géographie de son environnement urbain est un enjeu important pour les personnes déficientes visuelles. Des cartes tactiles en relief sont généralement utilisées mais elles présentent des limitations importantes (nombre limité d'informations, recours à une légende braille). Les nouvelles technologies permettent d'envisager des solutions innovantes. Nous avons conçu et développé une carte interactive accessible, en suivant un processus de conception participative. Cette carte est basée sur un dispositif multi-touch, une carte tactile en relief et une sortie sonore. Ce dispositif permet au sujet de recueillir des informations en double-cliquant sur certains objets de la carte. Nous avons démontré expérimentalement que ce prototype était plus efficace et plus satisfaisant pour des utilisateurs déficients visuels qu'une carte tactile simple. Nous avons également exploré et testé différents types d'interactions avancées accessibles pour explorer la carte. Cette thèse démontre l'importance des cartes tactiles interactives pour les déficients visuels et leur cognition spatiale.Knowing the geography of an urban environment is crucial for visually impaired people. Tactile relief maps are generally used, but they retain significant limitations (limited amount of information, use of braille legend, etc.). Recent technological progress allows the development of innovative solutions which overcome these limitations. In this thesis, we present the design of an accessible interactive map through a participatory design process. This map is composed by a multi-touch screen with tactile map overlay and speech output. It provides auditory information when tapping on map elements. We have demonstrated in an experiment that our prototype was more effective and satisfactory for visually impaired users than a simple raised-line map. We also explored and tested different types of advanced non-visual interaction for exploring the map. This thesis demonstrates the importance of interactive tactile maps for visually impaired people and their spatial cognition

    Head Related Transfer Function selection techniques applied to multimodal environments for spatial cognition

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    This thesis studies the pinna reflection model to extract the best possible HRTF for a user from a database. The performances of the selected HRTF are tested in a psychoacoustic experiment and compared with those recorded from KEMAR. This extraction increases the average performances in respect to the KEMAR. The selected HRTF is then integrated in a virtual multimodal environment together with the haptic device TAMO showing the relation and the benefit of audio in Orientation & Mobility task

    An investigation into automatically generated auditory route overviews and their role in strategic route planning.

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    PhD ThesesMaps are an integral tool for supporting travellers to preview and plan their journeys. However, the process is predominantly visual and thus inaccessible to people who are blind or visually impaired (BVI). This work investigates the usefulness and design of providing apriori overviews of pedestrian routes in audio to support BVI individuals make strategic decisions regarding their journeys and prepare for them. A user-led approach was adopted throughout, from needs-assessment and requirement gathering, to design decisions and eventually usability and usefulness evaluation. The overviews designed comprised auditory icons(AIs) to represent points of interest (PoIs), earcons for auditory brackets encapsulating repeating or extended PoIs, and speech for directions. The findings showed that the BVI users performed well in route reconstruction and recognition tasks during usability testing. The functional route information and AIs were effectively designed and useful in forming a mental model of the route, which improves with usage. The usefulness study showed that the users used this information to make strategic pre-navigation decisions, such as which route to choose, and to learn about the different features of the route. The main focus of their choices was the reason for travel. Moreover, the two major priorities for blind travellers were safety and not getting lost and the two major features of the route that affected route choice were PoIs and length of the route

    Properties of Visual Field Maps in Health and Disease

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    The visual world that surrounds us is represented in and processed by multiple topographically organised maps in the human brain. The organising principle underlying these retinotopic maps is also apparent across other sensory modalities and appears highly conserved across species. Moreover, the template for these visual maps is laid down during development, without the need for visual experience. This thesis binds and summarises seven publications describing work to characterise the functional properties of visual maps in the human brain. Initially, we describe TMS and fMRI measurements designed to probe the functional specificity of two spatially distinct but spatially adjacent maps, LO-1 and LO-2. Concurrently I developed software (visualisation tools) for precise dissection of these areas and to more broadly facilitate the visualisation of neuroimaging data. Our experiment revealed a double dissociation in the functional specificity of these areas, with preferential processing of orientation and shape information by LO-1 and LO-2, respectively. We then used fMRI to examine the effect of spatial attention on the responses measured from visual field maps. We showed that attention modulated visual responses by both enhancing attended locations and suppressing unattended locations; these effects were evident in the maps of early visual cortex and subcortical structures including the lateral geniculate and pulvinar nuclei. Finally, we examined the properties of visual field maps in patients with retinal lesions. Although maps can be abnormally organised with certain congenital visual deficits, we asked whether normally developed maps were able to reorganise when input to them is lost later in life, specifically due to central retinal lesions. Our measurements showed no evidence of reorganisation in the maps of patients with macular degeneration: the extent of activity measured in these maps was both highly predictable based on individual retinal lesions and could be reliably simulated in normally sighted individuals

    The Future of Information Sciences : INFuture2009 : Digital Resources and Knowledge Sharing

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    National Women's Studies Association Annual Conference: Feminist Transgressions

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    Digital program for the National Women's Studies Association 35th Annual Conference, held November 13-16, 2014, in San Juan, Puerto Rico

    Emerging Technologies

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    This monograph investigates a multitude of emerging technologies including 3D printing, 5G, blockchain, and many more to assess their potential for use to further humanity’s shared goal of sustainable development. Through case studies detailing how these technologies are already being used at companies worldwide, author Sinan Küfeoğlu explores how emerging technologies can be used to enhance progress toward each of the seventeen United Nations Sustainable Development Goals and to guarantee economic growth even in the face of challenges such as climate change. To assemble this book, the author explored the business models of 650 companies in order to demonstrate how innovations can be converted into value to support sustainable development. To ensure practical application, only technologies currently on the market and in use actual companies were investigated. This volume will be of great use to academics, policymakers, innovators at the forefront of green business, and anyone else who is interested in novel and innovative business models and how they could help to achieve the Sustainable Development Goals. This is an open access book
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