Enhanced sensor-based interaction techniques for mobile map-based applications
- Authors: Van Tonder, Bradley Paul
- Date: 2012
- Subjects: Cartography , User interfaces (Computer systems) -- Design , Digital mapping
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:10483 , http://hdl.handle.net/10948/d1012995
- Description: Mobile phones are increasingly being equipped with a wide range of sensors which enable a variety of interaction techniques. Sensor-based interaction techniques are particularly promising for domains such as map-based applications, where the user is required to interact with a large information space on the small screen of a mobile phone. Traditional interaction techniques have several shortcomings for interacting with mobile map-based applications. Keypad interaction offers limited control over panning speed and direction. Touch-screen interaction is often a two-handed form of interaction and results in the display being occluded during interaction. Sensor-based interaction provides the potential to address many of these shortcomings, but currently suffers from several limitations. The aim of this research was to propose enhancements to address the shortcomings of sensor-based interaction, with a particular focus on tilt interaction. A comparative study between tilt and keypad interaction was conducted using a prototype mobile map-based application. This user study was conducted in order to identify shortcomings and opportunities for improving tilt interaction techniques in this domain. Several shortcomings, including controllability, mental demand and practicality concerns were highlighted. Several enhanced tilt interaction techniques were proposed to address these shortcomings. These techniques were the use of visual and vibrotactile feedback, attractors, gesture zooming, sensitivity adaptation and dwell-time selection. The results of a comparative user study showed that the proposed techniques achieved several improvements in terms of the problem areas identified earlier. The use of sensor fusion for tilt interaction was compared to an accelerometer-only approach which has been widely applied in existing research. This evaluation was motivated by advances in mobile sensor technology which have led to the widespread adoption of digital compass and gyroscope sensors. The results of a comparative user study between sensor fusion and accelerometer-only implementations of tilt interaction showed several advantages for the use of sensor fusion, particularly in a walking context of use. Modifications to sensitivity adaptation and the use of tilt to perform zooming were also investigated. These modifications were designed to address controllability shortcomings identified in earlier experimental work. The results of a comparison between tilt zooming and Summary gesture zooming indicated that tilt zooming offered better results, both in terms of performance and subjective user ratings. Modifications to the original sensitivity adaptation algorithm were only partly successful. Greater accuracy improvements were achieved for walking tasks, but the use of dynamic dampening factors was found to be confusing. The results of this research were used to propose a framework for mobile tilt interaction. This framework provides an overview of the tilt interaction process and highlights how the enhanced techniques proposed in this research can be integrated into the design of tilt interaction techniques. The framework also proposes an application architecture which was implemented as an Application Programming Interface (API). This API was successfully used in the development of two prototype mobile applications incorporating tilt interaction.
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- Date Issued: 2012
Adaptive user interfaces for mobile map-based visualisation
- Authors: Van Tonder, Bradley Paul
- Date: 2008
- Subjects: Cartography , Maps -- Design , Digital mapping , Geographic information systems , User interfaces (Computer systems) -- Design
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:10470 , http://hdl.handle.net/10948/866 , Cartography , Maps -- Design , Digital mapping , Geographic information systems , User interfaces (Computer systems) -- Design
- Description: Mobile devices today frequently serve as platforms for the visualisation of map-based data. Despite the obvious advantages, mobile map-based visualisation (MMV) systems are often difficult to design and use. Limited screen space, resource constraints and awkward interaction mechanisms are among the many problems with which designers and users have to contend. Adaptive user interfaces (AUIs), which adapt to the individual user, represent a possible means of addressing the problems of MMV. Adaptive MMV systems are, however, generally designed in an ad-hoc fashion, making the benefits achieved difficult to replicate. In addition, existing models for adaptive MMV systems are either conceptual in nature or only address a subset of the possible input variables and adaptation effects. The primary objective of this research was to develop and evaluate an adaptive MMV system using a model-based approach. The Proteus Model was proposed to support the design of MMV systems which adapt in terms of information, visualisation and user interface in response to the user‟s behaviour, tasks and context. The Proteus Model describes the architectural, interface, data and algorithm design of an adaptive MMV system. A prototype adaptive MMV system, called MediaMaps, was designed and implemented based on the Proteus Model. MediaMaps allows users to capture, location-tag, organise and visualise multimedia on their mobile phones. Information adaptation is performed through the use of an algorithm to assist users in sorting media items into collections based on time and location. Visualisation adaptation is performed by adapting various parameters of the map-based visualisations according to user preferences. Interface adaptation is performed through the use of adaptive lists. An international field study of MediaMaps was conducted in which participants were required to use MediaMaps on their personal mobile phones for a period of three weeks. The results of the field study showed that high levels of accuracy were achieved by both the information and interface adaptations. High levels of user satisfaction were reported, with participants rating all three forms of adaptation as highly useful. The successful implementation of MediaMaps provides practical evidence that the model-based design of adaptive MMV systems is feasible. The positive results of the field study clearly show that the adaptations implemented were highly accurate and that participants found these adaptations to be useful, usable and easy to understand. This research thus provides empirical evidence that the use of AUIs can provide significant benefits for the visualisation of map-based information on mobile devices.
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- Date Issued: 2008
An appraisal of the production and utility of digital atlases in Africa: a case study of Swaziland
- Authors: Pettit, Louise Manda
- Date: 2000
- Subjects: Swaziland Atlases , Digital mapping , Geographic information systems , Cartography -- Data processing , Cartography -- Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4816 , http://hdl.handle.net/10962/d1005490 , Swaziland Atlases , Digital mapping , Geographic information systems , Cartography -- Data processing , Cartography -- Africa
- Description: This research will appraise the production and utility of digital atlases in an African context, using personal experience gained through the production of a digital atlas for Swaziland, the opinions obtained from other producers of African digital atlases and relevant literature. Since the 1950s, decision makers and researchers have viewed information as a powerful contributor to national development. Over the past thirty years, developed countries have increased the efficient collation and dissemination of geographic information through the utilization of the digital environment. The development of Geographic Information Systems (GIS) has increased the range of applications attainable in digital mapping projects. Applications have ranged from resource inventories to the monitoring of environmental degradation, crime patterns and service provision. The patchy history of data collection, analysis and mapping in Africa, has had a limiting effect on the ability of countries to identify, plan and control their resources efficiently. Despite the desire to automate the mapping process and reap some of the planning benefits evident in the developed world, Africa has not succeeded in mobilising full technological potential. Political instability, poor infrastructure, the absence of national policy guidelines, and a lack of skilled manpower are some of the issues which have limited utilization. Despite many of the hurdles faced by African countries, automated mapping and analysis technologies are still being pursued. The role of computers in the utilisation of data has become apparent through several means, one of which is the digital atlas. Analytical functions in many of these products allow situation modelling and provide superior graphic displays in comparison to their paper counterparts. Several African countries have embarked on the development of national digital databases and in some cases have produced digital national atlases. The potential to improve resource utilization, service provision and land use planning using these atlases, does exist. The production and utility of these atlases in an African context, however, needs closer assessment. "Computers don't clothe, don't cure, don't feed. Their power begins and ends with information. Their usefulness is therefore strictly linked to the ffectiveness of the information" (Gardner,1993:16).
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- Date Issued: 2000