www.dcs.gla.ac.uk/utopia Abstract. Though there have been many studies of computer based text reading, only a few have considered the small screens of handheld computers. This paper presents an investigation into the effect of varying font size between 2 and 16 point on reading text on a handheld computer. By using both older and younger participants the possible effects of age were examined. Reading speed and accuracy were measured and subjective views of participants recorded. Objective results showed that there was little difference in reading performance above 6 point, but subjective comments from participants showed a preference for sizes in the middle range. We therefore suggest, for reading tasks, that designers of interfaces for mobile computers provide fonts in the range of 8-12 point to maximize readability for the widest range of users. 1

This paper presents an ethnographic study, conducted to gain an insight of the practices around navigation of firefighters on the first line of intervention. We argue that the common approach of looking only at the technical aspects is incomplete. We show instead, that navigation of firefighters in ever-changing spaces is a collective craft or art, where technology is only one of the relevant pieces, but not the only one. Therefore design should take a deep look at existing navigation practices of firefighters. In order to identify relevant work practices, we conducted our ethnographic study to find out patterns of navigation work and based on our findings, we provide an outline of how the navigation practices can be supported by ubiquitous computing. Categories and Subject Descriptors H.5.1 [Information interfaces and presentation (e.g., HCI)]:

Users who operate in the field (e.g., maintenance personnel, geologists, archaeologists, tourists, first responders) bring often with them paper sheets (e.g., city maps, forms, technical plans, object descriptions) containing data needed for their activities. Even when this data is available in digital form, the

Abstract. One important issue for proactive computing is how users control and interact with the systems they will carry and have access to when they are out in the field. One solution is to use multimodal interaction (interaction using different combinations of sensory modalities) to allow people to interact in a range of different ways. This paper discusses gestural interaction as an alternative for input. This is advantageous as it does not require users to look at a display. For output non-speech audio and tactile displays are presented as alternatives to visual displays. The advantages with these types of displays are that they can be unobtrusive and do not require a user’s visual attention. The combination of these underutilised senses has much potential to create effective interfaces for proactive systems. 1.

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Mobile devices have much potential to support older adults in their daily lives. However older adults have reported that they find mobile devices, such as existing mobile phones, difficult to learn to use. We argue that more research is needed to improve the learnability of mobile software applications for older adults. We present three different approaches for improving mobile device learnability: improving graphical icons, using multilayered interfaces, and augmenting the mobile interface. Categories and Subject Descriptors H.5 Information interfaces and presentation (e.g., HCI); H.5.2

We investigated the usefulness transparency can play in increasing the display space of mobile devices in navigation scenarios. Two different systems that used transparency to display a map and image of a point of interest (POI) were compared to a control. Significant variations were identified in the strategies employed, with a strong user preference towards the transparency conditions. Significant variations in time or distance taken were not identified between conditions, although results indicate strong avenues for future investigation.

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Most existing Global Positioning System (GPS)-based vehicle navigation systems (also termed route guidance systems) utilize distance within their turn-by-turn navigation directions. For example, a system might give a voice instruction like ”turn left in 0.2 mile”. However, human drivers usually use landmarks to help their navigation. Some previous research has shown that there are performance-related benefits in using landmarks instead of distance for navigation. The goal of this dissertation is to develop multimedia techniques that can be used for achieving landmarkbased navigation using computer vision and machine learning techniques. This dissertation makes contributions in landmark labeling, detection, recognition and the human vehicle interfaces. Landmark labeling is essential for development of landmark recognition systems and using a landmark-based navigation system. The first contribution of this dissertation is a semi-supervised learning-based approach for labeling landmarks in images. The proposed approaches, SmartLabel and SmartLabel-2, minimize user input in labeling landmarks. Text on road signs carries much useful information for driving. The second contribution is an automatic

A global increase in aging population, combined with a growing number of people with dementia, creates new challenges to develop guiding technology for people with memory disturbances in their daily activities. In this study we have tested the prototype of a wayfinding aid using predefined routes. The orientation advice was given through three modalities, visual, audio and tactile signals, two of which were used at a time. Nine subjects, aged 59–90 years (with a median age of 84 years) participated in the user study at a rehabilitation unit in Pyhäjärvi, Finland. Their severity of dementia ranged between mild and severe, and walking abilities ranged from “frail to hobby skier”. In addition, two elderly persons were recruited as control subjects. In most cases, the orientation with the wayfinding aid on predefined routes succeeded, with a few misinterpretations. The most common difficulties included: straying from the defined route, finding the right door, and the attractions of real-life context like other people. The severity of dementia didn’t seem to predict success in orientation with the wayfinding aid. Using the landmarks wasn’t as successful as using “left”, “right” and “go straight on” commands as the wayfinding advice.