Human-machine cooperative or co-robotics has been recognized as the next generation of robotics. In contrast to current systems that use limited-reasoning strategies or address problems in narrow contexts, new co-robot systems will be characterized by their flexibility, resourcefulness, varied modeling or reasoning approaches, and use of real-world data in real time, demonstrating a level of intelligence and adaptability seen in humans and animals. The research I focused is in the two sub-field of co-robotics: teleoperation and telepresence. We firstly explore the ways of teleoperation using mixed reality techniques. I proposed a new type of display: hybrid-reality display (HRD) system, which utilizes commodity projection device to project captured video frame onto 3D replica of the actual target surface. It provides a direct alignment between the frame of reference for the human subject and that of the displayed image. The advantage of this approach lies in the fact that no wearing device needed for the users, providing minimal intrusiveness and accommodating users eyes during focusing. The field-of-view is also significantly increased. From a user-centered design standpoint, the HRD is motivated by teleoperation accidents, incidents, and user research in military reconnaissance etc. Teleoperation in these environments is compromised by the Keyhole Effect, which results from the limited field of view of reference. The technique contribution of the proposed HRD system is the multi-system calibration which mainly involves motion sensor, projector, cameras and robotic arm. Due to the purpose of the system, the accuracy of calibration should also be restricted within millimeter level. The followed up research of HRD is focused on high accuracy 3D reconstruction of the replica via commodity devices for better alignment of video frame. Conventional 3D scanner lacks either depth resolution or be very expensive. We proposed a structured light scanning based 3D sensing system with accuracy within 1 millimeter while robust to global illumination and surface reflection. Extensive user study prove the performance of our proposed algorithm. In order to compensate the unsynchronization between the local station and remote station due to latency introduced during data sensing and communication, 1-step-ahead predictive control algorithm is presented. The latency between human control and robot movement can be formulated as a linear equation group with a smooth coefficient ranging from 0 to 1. This predictive control algorithm can be further formulated by optimizing a cost function. We then explore the aspect of telepresence. Many hardware designs have been developed to allow a camera to be placed optically directly behind the screen. The purpose of such setups is to enable two-way video teleconferencing that maintains eye-contact. However, the image from the see-through camera usually exhibits a number of imaging artifacts such as low signal to noise ratio, incorrect color balance, and lost of details. Thus we develop a novel image enhancement framework that utilizes an auxiliary color+depth camera that is mounted on the side of the screen. By fusing the information from both cameras, we are able to significantly improve the quality of the see-through image. Experimental results have demonstrated that our fusion method compares favorably against traditional image enhancement/warping methods that uses only a single image.

published_or_final_version / Computer Science and Information Systems / Master / Master of Philosophy

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The use of computers in the classroom could allow both educators and learners to achieve new capabilities. There are underlying factors, however, that are obstructing the adoption rate of computer use for instructional purposes in schools. The study focused on these problems with a view to determining which critical success factors promote a higher adoption rate of computer usage in education. This study derived its theoretical framework from various technology adoption and educational models Methodology: The nature of the study required a . Furthermore, it investigated ways in which computer technology could enhance learning. mixed methods approach to be employed, making use of both quantitative and qualitative data. Two questionnaires, one for the educators and one for the principals of the schools were hand-delivered to 60 secondary schools. Exploratory factor analysis and various internal consistency measures were used to assess and analyse the data.Conclusion: Educationists and policy-makers must include all principals and educators when technological innovations are introduced into schools. All these role-players need to be cognisant of the implications if innovations are not appropriately implemented. Including the use of computers in educator training programs is important so that pre-service educators can see the benefits of using the computer in their own teaching.

This thesis reports on a usability study conducted on the Virtual Learning Spaces (VLS) computerbased educational adventure game. The aim of the game is to improve the acquisition of knowledge through play in an interactive, entertaining and intrinsically motivating computer-based environment. The objective of this study centred on assessing the quality of the VLS game user interface, and determining faults and problems that may hinder implementation Literature on usability of virtual reality educational game systems and related phenomenon of usability of other types of computer application systems was reviewed, including, to a lesser extent, literature on usability of web pages. The major issues of interest included, usability issues concerning principles of good user interface design, factors that influence how a user interface promotes user satisfaction and the objectives of playing the game, from player, game and the game as medium of learning perspectives. These principles provided a set of usability requirements for the VLS game user interface on which the evaluation was based. A series of data collection methods comprising a cognitive walk through, heuristic evaluation, usability testing and post-test questionnaire, were used in this study. Despite some usability problems, results indicate that the VLS user interface design conformed, extensively, to the principles of good user interface design in appearance, interaction and user help. It was also found to be engaging, comprehensible and unbiased (in terms of gender and variable computer skills). / Thesis (M.A.)-University of KwaZulu-Natal, Durban, 2004.

This dissertation was inspired by difficult decisions patients of chronic diseases have to make about about treatment options in light of uncertainty. We look at rheumatoid arthritis (RA), a chronic, autoimmune disease that primarily affects the synovial joints of the hands and causes pain and deformities. In this work, we focus on several parts of a computer-based decision tool that patients can interact with using gestures, ask questions about the disease, and visualize possible futures. We propose a hand gesture based interaction method that is easily setup in a doctor's office and can be trained using a custom set of gestures that are least painful. Our system is versatile and can be used for operations like simple selections to navigating a 3D world. We propose a point distribution model (PDM) that is capable of modeling hand deformities that occur due to RA and a generalized fitting method for use on radiographs of hands. Using our shape model, we show novel visualization of disease progression. Using expertly staged radiographs, we propose a novel distance metric learning and embedding technique that can be used to automatically stage an unlabeled radiograph. Given a large set of expertly labeled radiographs, our data-driven approach can be used to extract different modes of deformation specific to a disease.

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Research in team science suggests strategies for addressing difficulties that groups face when working together. This dissertation examines how student teams work in project based learning (PBL) environments, with the goal of creating strategies and technology to improve collaboration. The challenge of working in such a group is that the members frequently come from different backgrounds and thus have different ideas on how to accomplish a project. In these groups, teamwork and production of successful solutions depends on whether members consider each other’s dissimilar perspectives. However, the lack of a shared history means that members may have difficulty in taking the time to share and build knowledge collectively. The ultimate goal of my research is to design strategies and technology to improve the inner workings of PBL groups so that they will learn from each other and produce successful outcomes in collaborative settings. The field of computer supported collaborative learning has made much progress on designing, implementing, and evaluating environments that support project based learning. However, most existing research concerns students rather than instructors. Therefore, in my initial research, I explore the needs of the instructors in conducting student assessments (studies one, two). These studies identify five different group processes that are of importance from the instructors’ perspective. My subsequent research focuses on one of them, namely the process of knowledge co-construction, which is a process that instructors have significant difficulty in assessing. In order to support the assessment of the knowledge co-construction process, my research has progressed along two axes: (a) identifying conditions that support the knowledge co-construction process and its relationship to learning and knowledge transfer (studies three, four, and five), and (b) automatically monitoring the knowledge co-construction process using natural language processing and machine learning (studies six ~ nine). Studies five and eight look at a specific type of knowledge co-construction process called the idea co-construction process (ICC). ICC is the process of taking up, transforming, or otherwise building on an idea expressed earlier in a conversation. I argue that ICC is essential for groups to function well in terms of knowledge sharing and perspective taking.

To facilitate everyday activities, context-aware applications use sensors to detect what is happening and use increasingly complex mechanisms (e.g., by using big rule-sets or machine learning) to infer the user's context and intent. For example, a mobile application can recognize that the user is in a conversation and suppress any incoming calls. When the application works well, this implicit sensing and complex inference remain invisible. However, when it behaves inappropriately or unexpectedly, users may not understand its behavior. This can lead users to mistrust, misuse, or even abandon it. To counter this lack of understanding and loss of trust, context-aware applications should be intelligible, capable of explaining their behavior. We investigate providing intelligibility in context-aware applications and evaluate its usefulness to improve user understanding and trust in context-aware applications. Specifically, this thesis supports intelligibility in context-aware applications through the provision of explanations that answer different question types, such as: Why did it do X? Why did it not do Y? What if I did W, What will it do? How can I get the application to do Y? This thesis takes a three-pronged approach to investigating intelligibility by (i) eliciting the user requirements for intelligibility, to identify what explanation types end-users are interested in asking context-aware applications, (ii) supporting the development of intelligible context-aware applications with a software toolkit and the design of these applications with design and usability recommendations, and (iii) evaluating the impact of intelligibility on user understanding and trust under various situations and application reliability, and measuring how users use an interactive intelligible prototype. We show that users are willing to use well-designed intelligibility features, and this can improve user understanding and trust in the adaptive behavior of context-aware applications.

Thesis (Ph.D.)--University of Melbourne, Dept. of Information Systems and Faculty of Architecture, Building and Planning 2006. / Typescript. Includes bibliographical references (leaves 261-275).