Through eye tracking technology, scientists have explored the eyes diverse aspects and capabilities. There are many potential applications that benefit from eye tracking. Each benefit from advances in computer technology as this results in improved quality and decreased costs for eye-tracking systems.This thesis presents a computer vision-based eye tracking system for human computer interaction. The eye tracking system allows the user to indicate a region of interest in a large data space and to magnify that area, without using traditional pointer devices. Presented is an iris tracking algorithm adapted from Camshift; an algorithm originally designed for face or hand tracking. Although the iris is much smaller and highly dynamic. the modified Camshift algorithm efficiently tracks the iris in real-time. Also presented is a method to map the iris centroid, in video coordinates to screen coordinates; and two novel calibration techniques, four point and one-point calibration. Results presented show that the accuracy for the proposed one-point calibration technique exceeds the accuracy obtained from calibrating with four points. The innovation behind the one-point calibration comes from using observed eye scanning behaviour to constrain the calibration process. Lastly, the thesis proposes a non-linear visualisation as an eye-tracking application, along with an implementation.

This thesis develops and presents a design methodology that enables designers to work with the moving body in the design and evaluation of interactive, immersive environments built on motion-sensing technologies. The notion of making strange, that underpins the methodology, calls for designers to re-examine and revitalise their assumptions and conceptions of the moving body through bodily-based movement inquiries. This thesis addresses research questions about ways of understanding human movement, of describing and representing human movement and of accessing the felt experience of the moving body in the emerging field of movement-based interaction design. The research questions were explored through a series of three distinct, yet related, projects, each one focusing on different aspects of designing for moving bodies in interactive, immersive environments. The first project analysed an existing interactive product, Sony Playstation2c EyetoyTM, as a prototype of future movement-based interactive, immersive environments. The second project involved the design and development of a specific interactive, immersive artwork, Bystander. The third project worked with trained dancers and physical performers in a constructed design situation. The contributions of this research are first and foremost the design methodology of Moving and Making Strange: a design approach to movement-based interaction that prioritises the lived experience of movement by both designers and users and values the creative potential of the experiential, moving body. It consists of methods and tools for exploring, experiencing, describing, representing and generating movement that enable designers to shift between the multiple perspectives of the mover, the observer and the machine. It makes particular contributions as follows: • Laban movement analysis and Labanotation as a design tool. • Moving-Sensing schema: Suchman’s analytic framework adapted as a design tool. • Extension of existing human-centred design tools to explicitly represent moving bodies, in the form of movement-oriented personas and movementoriented scenarios. • Patterns of watching: a catalogue of audience behaviour in terms of movements and stillness in relation to engagement with a specific interactive, immersive artwork. • New methods for generating, enacting and experiencing movement, sourced from dance and movement improvisation practices.

This dissertation presents interaction techniques for 3D modelling of large structures in outdoor augmented reality environments. Augmented reality is the process of registering projected computer-generated images over a user's view of the physical world. With the use of a mobile computer, augmented reality can also be experienced in an outdoor environment. Working in a mobile outdoor environment introduces new challenges not previously encountered indoors, requiring the development of new user interfaces to interact with the computer. Current AR systems only support limited interactions and so the complexity of applications that can be developed is also limited. This dissertation describes a number of novel contributions that improve the state of the art in augmented reality technology. / thesis (PhD)--University of South Australia, 2004.

This thesis is concerned with temporal factors from the perspective of the interactive designer/interface designer and usability as a construct for guiding design activity. The research reported herein examines the many factors which emerge when considering the name of interaction at the user interface. Temporal Aspects of Usability (TAU) is presented as a multivariate construct. It is neither a property that exists 'in the head alone' not is it an aspect of the system but rather an emergent property arising from task based interactions. From a theoretical perspective, it is argued that the inclusion of temporal considerations to the task model more fully specifies 'Usability' as a design construct. A model of TAU is evolved and validated utilizing situated interviews with designers. This resulted in an Enhanced model of TAU. A method for developing temporally informed task models, KAT-LITTER (Leveraging Interactions Through Effective Responses), provides temporal design heuristics as the confluence of, KAT (Knowledge Analysis of Task) a task analysis method, and the enhanced TAU model. As a method, KAT-LITTER is device independent, data centered, domain specific and necessarily independent of existing implementations. A process evaluation of KAT-LITTER showed that it influenced the design process in two significant ways: firstly, designers using KAT-LITTER spent more time reasoning about temporal issues than designers using KAT alone, and secondly these same designers considered a broader spectrum of temporal issues. The development of TAU, its accompanying method, KAT-LITTER, complete with a notational system for analysis represent a significant step forward.

From a user's perspective, product quality has typically been equated to usability, where the primary focus is performance (i.e. efficiency and effectiveness) and user satisfaction. This view on quality has been adequate to validate the 'fitness for purpose' for many products. However, many other products, such as computer games or at-home-technologies, are not based solely on performance-based qualities. By defining and validating the quality of these non-performance-based technologies using the same measures as performance-based technologies fails to address a key quality � the ability of the product to create fun, enjoyment, or other user affective experiences. This thesis investigates system quality issues in non-performance-based technologies, primarily addressing affect. It explores what affect is in relation to system quality, how can affect impact quality in use, what product characteristics can aid in the creation of positive user affect, and how to validate whether a product successfully created the desired user affect. To begin, current knowledge about the relationship between systems development, quality in use, and affect is summarised. Concepts used synonymously with affect were studied (e.g. satisfaction, user experience, emotion). It was found that these are related to affect, but are not affect themselves. Following this, a broad survey asking users to identify product characteristics that create positive affect during use is reported on. Results showed that the system characteristics of learnability, feedback, curiosity, and user cooperation can each increase and enhance positive user affect experienced. If it is an aim for the system to create an affective experience in a user then this should be considered a requirement of the system; and as a requirement, it is necessary to validate that it achieves this aim. To this end, a laboratory study exploring psycho-physiology and cued-recall debrief as methods to evaluate user affect was conducted. Results revealed that both methods show promise for evaluating user affect. Cued-recall is capable of identifying specific user affects, but is limited because it relies on the user to report these affects. Physiological measures can objectively identify when a person is experiencing affect, but is limited because it is not possible to determine what affect is being experienced. Combined, these methods represent an optimal and viable evaluation method for user affect.

Information technology research over the past two decades suggests that the installation and use of computers fundamentally affects the structure and function of organisations and, m particular, the workers in these organizations. Following the release of the IBM Personal Computer in 1982, microcomputers have become an integral part of most work environments. The accounting services industry, in particular, has felt the impact of this ‘microcomputer revolution’. In Big Six accounting firms, there is almost one microcomputer for each professional accountant employed, Notwithstanding this, little research has been done on the effect of microcomputers on the work outcomes of professional accountants working in these firms. This study addresses this issue. It assesses, in an organisational setting, how accountant’ perceptions of ease of use and usefulness of microcomputers act on their computer anxieties, microcomputer attitudes and use to affect their job satisfaction and job performance. The research also examines how different types of human-computer interfaces affect the relationships between accountants' beliefs about microcomputer utility and ease of use, computer anxiety, microcomputer attitudes and microcomputer use. To attain this research objective, a conceptual model was first developed, The model indicates that work outcomes (job satisfaction and job performance) of professional accountants using microcomputers are influenced by users' perceptions of ease of use and usefulness of microcomputers via paths through (a) the level of computer anxiety experienced by users, (b) the general attitude of users toward using microcomputers, and (c) the extent to which microcomputers are used by individuals. Empirically testable propositions were derived from the model to test the postulated relationships between these constructs. The study also tested whether or not users of different human-computer interfaces reacted differently to the perceptions and anxieties they hold about microcomputers and their use in the workplace. It was argued that users of graphical interfaces, because of the characteristics of those interfaces, react differently to their perceptions and anxieties about microcomputers compared with users of command-line (or textual-based) interfaces. A passive-observational study in a field setting was used to test the model and the research propositions. Data was collected from 164 professional accountants working in a Big Six accounting firm in a metropolitan city in Australia. Structural equation modelling techniques were used to test the, hypothesised causal relationships between the components comprising the general research model. Path analysis and ordinary least squares regression was used to estimate the parameters of the model and analyse the data obtained. Multisample analysis (or stacked model analysis) using EQS was used to test the fit of the model to the data of the different human-computer interface groups and to estimate the parameters for the paths in those different groups. The results show that the research model is a good description of the data. The job satisfaction of professional accountants is directly affected by their attitude toward using microcomputers and by microcomputer use itself. However, job performance appears to be only directly affected by microcomputer attitudes. Microcomputer use does not directly affect job performance. Along with perceived ease of use and perceived usefulness, computer anxiety is shown to be an important determinant of attitudes toward using microcomputers - higher levels of computer anxiety negatively affect attitudes toward using microcomputers. Conversely, higher levels of perceived ease of use and perceived usefulness heighten individuals' positive attitudes toward using microcomputers. Perceived ease of use and perceived usefulness also indirectly affect microcomputer attitudes through their effect on computer anxiety. The results show that higher levels of perceived ease of use and perceived usefulness result in lower levels of computer anxiety. A surprising result from the study is that while perceived ease of use is shown to directly affect the level of microcomputer usage, perceived usefulness and attitude toward using microcomputers does not. The results of the multisample analysis confirm that the research model fits the stacked model and that the stacked model is a significantly better fit if specific parameters are allowed to vary between the two human-computer interface user groups. In general, these results confirm that an interaction exists between the type of human-computer interface (the variable providing the grouping) and the other variables in the model The results show a clear difference between the two groups in the way in which perceived ease of use and perceived usefulness affect microcomputer attitude. In the case of users of command-line interfaces, these variables appear to affect microcomputer attitude via an intervening variable, computer anxiety, whereas in the graphical interface user group the effect occurs directly. Related to this, the results show that perceived ease of use and perceived usefulness have a significant direct effect on computer anxiety in command-line interface users, but no effect at all for graphical interface users. Of the two exogenous variables only perceived ease of use, and that in the case of the command-line interface users, has a direct significant effect on extent of use of microcomputers. In summary, the research has contributed to the development of a theory of individual adjustment to information technology in the workplace. It identifies certain perceptions, anxieties and attitudes about microcomputers and shows how they may affect work outcomes such as job satisfaction and job performance. It also shows that microcomputer-interface types have a differential effect on some of the hypothesised relationships represented in the general model. Future replication studies could sample a broader cross-section of the microcomputer user community. Finally, the results should help Big Six accounting firms to maximise the benefits of microcomputer use by making them aware of how working with microcomputers affects job satisfaction and job performance.

This thesis develops and presents a design methodology that enables designers to work with the moving body in the design and evaluation of interactive, immersive environments built on motion-sensing technologies. The notion of making strange, that underpins the methodology, calls for designers to re-examine and revitalise their assumptions and conceptions of the moving body through bodily-based movement inquiries. This thesis addresses research questions about ways of understanding human movement, of describing and representing human movement and of accessing the felt experience of the moving body in the emerging field of movement-based interaction design. The research questions were explored through a series of three distinct, yet related, projects, each one focusing on different aspects of designing for moving bodies in interactive, immersive environments. The first project analysed an existing interactive product, Sony Playstation2c EyetoyTM, as a prototype of future movement-based interactive, immersive environments. The second project involved the design and development of a specific interactive, immersive artwork, Bystander. The third project worked with trained dancers and physical performers in a constructed design situation. The contributions of this research are first and foremost the design methodology of Moving and Making Strange: a design approach to movement-based interaction that prioritises the lived experience of movement by both designers and users and values the creative potential of the experiential, moving body. It consists of methods and tools for exploring, experiencing, describing, representing and generating movement that enable designers to shift between the multiple perspectives of the mover, the observer and the machine. It makes particular contributions as follows: • Laban movement analysis and Labanotation as a design tool. • Moving-Sensing schema: Suchman’s analytic framework adapted as a design tool. • Extension of existing human-centred design tools to explicitly represent moving bodies, in the form of movement-oriented personas and movementoriented scenarios. • Patterns of watching: a catalogue of audience behaviour in terms of movements and stillness in relation to engagement with a specific interactive, immersive artwork. • New methods for generating, enacting and experiencing movement, sourced from dance and movement improvisation practices.

Thesis (Ph. D.)--University of Nevada, Reno, 2006. / "May 2006." Includes bibliographical references (leaves 131-137). Online version available on the World Wide Web.

Thesis (M.S.)--University of Nevada, Reno, 2006. / "May, 2006." Includes bibliographical references (leaves 77-80). Online version available on the World Wide Web.

Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 35-37). Also available on the World Wide Web.