Vision-based topological mapping and localisation

Competent navigation in an environment is a major requirement for an autonomous mobile robot to accomplish its mission. Nowadays, many successful systems for navigating a mobile robot use an internal map which represents the environment in a detailed geometric manner. However, building, maintaining and using such environment maps for navigation is difficult because of perceptual aliasing and measurement noise. Moreover, geometric maps require the processing of huge amounts of data which is computationally expensive. This thesis addresses the problem of vision-based topological mapping and localisation for mobile robot navigation. Topological maps are concise and graphical representations of environments that are scalable and amenable to symbolic manipulation. Thus, they are well-suited for basic robot navigation applications, and also provide a representational basis for the procedural and semantic information needed for higher-level robotic tasks. In order to make vision-based topological navigation suitable for inexpensive mobile robots for the mass market we propose to characterise key places of the environment based on their visual appearance through colour histograms. The approach for representing places using visual appearance is based on the fact that colour histograms change slowly as the field of vision sweeps the scene when a robot moves through an environment. Hence, a place represents a region of the environment rather than a single position. We demonstrate in experiments using an indoor data set, that a topological map in which places are characterised using visual appearance augmented with metric clues provides sufficient information to perform continuous metric localisation which is robust to the kidnapped robot problem. Many topological mapping methods build a topological map by clustering visual observations to places. However, due to perceptual aliasing observations from different places may be mapped to the same place representative in the topological map. A main contribution of this thesis is a novel approach for dealing with the perceptual aliasing problem in topological mapping. We propose to incorporate neighbourhood relations for disambiguating places which otherwise are indistinguishable. We present a constraint based stochastic local search method which integrates the approach for place disambiguation in order to induce a topological map. Experiments show that the proposed method is capable of mapping environments with a high degree of perceptual aliasing, and that a small map is found quickly. Moreover, the method of using neighbourhood information for place disambiguation is integrated into a framework for topological off-line simultaneous localisation and mapping which does not require an initial categorisation of visual observations. Experiments on an indoor data set demonstrate the suitability of our method to reliably localise the robot while building a topological map.

ePortfolio use by university students in Australia: Informing excellence in policy and practice

In mid 2007, the Australian Learning and Teaching Council (ALTC), formerly the Carrick Institute for Learning and Teaching in Higher Education, commissioned an intensive research project to examine the use of ePortfolios by university students in Australia. The project was awarded to a consortium of four universities: Queensland University of Technology as lead institution, The University of Melbourne, University of New England and University of Wollongong.---------- The overarching aim of the research project, which was given the working title of the Australian ePortfolio Project, was to examine the current levels of ePortfolio practice in Australian higher education. The principal project goals sought to provide an overview and analysis of the national and international ePortfolio contexts, document the types of ePortfolios used in Australian higher education, examine the relationship with the National Diploma Supplement project funded by the Federal government, identify any significant issues relating to ePortfolio implementation, and offer guidance about future opportunities for ePortfolio development. The research findings revealed that there was a high level of interest in the use of ePortfolios in the context of higher education, particularly in terms of the potential to help students become reflective learners who are conscious of their personal and professional strengths and weaknesses, as well as to make their existing and developing skills more explicit. There were some good examples of early adoption in different institutions, although this tended to be distributed across the sector. The greatest use of ePortfolios was recorded in coursework programs, rather than in research programs, with implementation generally reflecting subject-specific or program-based activity, as opposed to faculty- or university-wide activity. Accordingly, responsibility for implementation frequently rested with the individual teaching unit, although an alternative centralised model of coordination by ICT services, careers and employment or teaching and learning support was beginning to emerge. The project report concludes with a series of recommendations to guide the process, drawing on the need for open dialogue and effective collaboration between the stakeholders across the range of contexts: government policy, international technical standards, academic policy, and learning and teaching research and practice.

ePortfolio use by university students in Australia : Developing a sustainable community of practice

This report documents Stage Two of the Australian ePortfolio Project (AeP2), to specifically explore the current scope of national and international ePortfolio communities of practice in order to identify the factors that have contributed to their success and sustainability. The study has built on Stage One of the Australian ePortfolio Project (Hallam, Harper, McCowan, Hauville, McAllister, & Creagh, 2008), which outlined the broad range of issues and challenges, as well as significant opportunities, that faced the higher education sector in terms of ePortfolio practice, to determine how the emergent community of ePortfolio researchers and practitioners in Australia might be advanced. ---------- The overarching aims of this project were to focus on building the Australian community of practice through an online forum and further symposium activities. Through the research activities the project sought to generate the following major outcomes: develop a forum within the ALTC Exchange to support an ePortfolio community of practice; develop strategies to encourage interest in and engagement with community of practice activities; develop and promote resources to support the diverse stakeholders in ePortfolio practice; collaborate in the establishment of a cross-sector ePortfolio community of practice; host a second Australian ePortfolio Symposium (AeP2) to disseminate the findings from the Australian ePortfolio Project, to explore innovative practice in ePortfolio use in higher education, to articulate policy developments, and to stimulate discussion on international ePortfolio issues; host an associated trade display as a forum for strengthening the higher education sector’s understanding of the features and functionality of ePortfolio platforms; develop resources to support an ePortfolio symposium model that may be adopted for future events. ----------- The project activities encompassed a survey of stakeholders, a program of semi-structured interviews with community managers and a series of case studies depicting successful ePortfolio communities. The survey of ePortfolio practitioners sought to determine the potential value of an ePortfolio CoP, the preferred focus for and the desired features of such a community, as well as the options for the technical and social architecture of an online forum. Through the semi-structured interviews it was possible to examine current examples of CoP activity, to identify the critical success factors and the challenges faced by individual ePortfolio CoPs, so that the attributes of good practice could be presented. The data collected in the interviews contributed to the development of 14 case studies, which have been beneficial in illustrating the diverse nature of CoPs in Australia and overseas.----------- The report presents a rich picture of national and international ePortfolio communities of practice, with an examination of the factors that have contributed to their success and sustainability.

Up the e-learning curve : ensuring quality online education within an Australian university

The paper describes the implementation of a project within Australian Catholic University designed to launch the Faculties into online education in a manner which ensured quality in all aspects of the teaching-learning experiences of academics and students. Key elements of the strategic approach adopted by the project leaders, including the involvement of a specialist commercial provider of web-based delivery systems as a partner in the project, mechanisms to support the initiative through the first stages, careful choice of the programs offered online, and staff development matched to the emerging needs of those involved in the teaching of courses, are described. Challenges encountered in the implementation process, and the factors which assisted in overcoming these problems are identified. The paper draws upon this experience to raise some important issues relevant to the successful introduction of online education as an integral component of the teaching repertoire of Faculties.

Students’ perceptions, experiences and beliefs about Facebook in subjects at an Australian university

This paper reports on students’ perceptions, experiences and beliefs about the voluntary use of Facebook in Advertising, Law, Nursing and Creative Industries’ subjects at an Australian University. The researchers conducted in-depth interviews with students and the transcriptions were analysed using the constant comparison method. This resulted in a number of emergent themes, of which six are explored in this paper. The findings suggest that students are quite divergent in their responses to academics using Facebook in their subjects. They do not always see its relevance to the subject and are somewhat ambivalent about how it facilitates peer-to-peer relationships or a better relationship with the lecturer. The study also identifies themes relating to cynicism and intrusion into social spaces.

Coordinated research support services at Queensland University of Technology, Australia

Queensland University of Technology (QUT) is a large multidisciplinary university located in Brisbane, Queensland, Australia. QUT is increasing its research focus and is developing its research support services. It has adopted a model of collaboration between the Library, High Performance Computing and Research Support (HPC) and more broadly with Information Technology Services (ITS). Research support services provided by the Library include the provision of information resources and discovery services, bibliographic management software, assistance with publishing (publishing strategies, identifying high impact journals, dealing with publishers and the peer review process), citation analysis and calculating authors’ H Index. Research data management services are being developed by the Library and HPC working in collaboration. The HPC group within ITS supports research computing infrastructure, research development and engagement activities, researcher consultation, high speed computation and data storage systems , 2D/ 3D (immersive) visualisation tools, parallelisation and optimization of research codes, statistics/ data modeling training and support (both qualitative and quantitative) and support for the university’s central Access Grid collaboration facility. Development and engagement activities include participation in research grants and papers, student supervision and internships and the sponsorship, incubation and adoption of new computing technologies for research. ITS also provides other services that support research including ICT training, research infrastructure (networking, data storage, federated access and authorization, virtualization) and corporate systems for research administration. Seminars and workshops are offered to increase awareness and uptake of new and existing services. A series of online surveys on eResearch practices and skills and a number of focus groups was conducted to better inform the development of research support services. Progress towards the provision of research support is described within the context organizational frameworks; resourcing; infrastructure; integration; collaboration; change management; engagement; awareness and skills; new services; and leadership. Challenges to be addressed include the need to redeploy existing operational resources toward new research support services, supporting a rapidly growing research profile across the university, the growing need for the use and support of IT in research programs, finding capacity to address the diverse research support needs across the disciplines, operationalising new research support services following their implementation in project mode, embedding new specialist staff roles, cross-skilling Liaison Librarians, and ensuring continued collaboration between stakeholders.

Life in the 'real world': a profile of Queensland University of Technology Library and Information Science graduates.

A graduate destination survey can provide a snap shot in time of a graduate’s career progression and outcome. This paper will present the results of a Queensland University of Technology study exploring the employment outcomes of students who had completed a library and information science course from the Faculty of Information Technology between 2000 and 2008. Seventy-four graduates completed an online questionnaire administered in July 2009. The study found that 90% of the graduates surveyed were working and living in Queensland, with over three quarters living and working in Brisbane. Nearly 70% were working full-time, while only 1.4% indicating that they were unemployed and looking for work. Over 80% of the graduates identified themselves as working in “librarianship”. This study is the first step in understanding the progression and destination of QUT’s library and information science graduates. It is recommended that this survey becomes an ongoing initiative so that the results can be analysed and compared over time.

Reliability analysis of transform-based stereo matching techniques, and a new matching constraint

Stereo vision is a method of depth perception, in which depth information is inferred from two (or more) images of a scene, taken from different perspectives. Practical applications for stereo vision include aerial photogrammetry, autonomous vehicle guidance, robotics and industrial automation. The initial motivation behind this work was to produce a stereo vision sensor for mining automation applications. For such applications, the input stereo images would consist of close range scenes of rocks. A fundamental problem faced by matching algorithms is the matching or correspondence problem. This problem involves locating corresponding points or features in two images. For this application, speed, reliability, and the ability to produce a dense depth map are of foremost importance. This work implemented a number of areabased matching algorithms to assess their suitability for this application. Area-based techniques were investigated because of their potential to yield dense depth maps, their amenability to fast hardware implementation, and their suitability to textured scenes such as rocks. In addition, two non-parametric transforms, the rank and census, were also compared. Both the rank and the census transforms were found to result in improved reliability of matching in the presence of radiometric distortion - significant since radiometric distortion is a problem which commonly arises in practice. In addition, they have low computational complexity, making them amenable to fast hardware implementation. Therefore, it was decided that matching algorithms using these transforms would be the subject of the remainder of the thesis. An analytic expression for the process of matching using the rank transform was derived from first principles. This work resulted in a number of important contributions. Firstly, the derivation process resulted in one constraint which must be satisfied for a correct match. This was termed the rank constraint. The theoretical derivation of this constraint is in contrast to the existing matching constraints which have little theoretical basis. Experimental work with actual and contrived stereo pairs has shown that the new constraint is capable of resolving ambiguous matches, thereby improving match reliability. Secondly, a novel matching algorithm incorporating the rank constraint has been proposed. This algorithm was tested using a number of stereo pairs. In all cases, the modified algorithm consistently resulted in an increased proportion of correct matches. Finally, the rank constraint was used to devise a new method for identifying regions of an image where the rank transform, and hence matching, are more susceptible to noise. The rank constraint was also incorporated into a new hybrid matching algorithm, where it was combined a number of other ideas. These included the use of an image pyramid for match prediction, and a method of edge localisation to improve match accuracy in the vicinity of edges. Experimental results obtained from the new algorithm showed that the algorithm is able to remove a large proportion of invalid matches, and improve match accuracy.

Multiple camera management using wide baseline matching

Camera calibration information is required in order for multiple camera networks to deliver more than the sum of many single camera systems. Methods exist for manually calibrating cameras with high accuracy. Manually calibrating networks with many cameras is, however, time consuming, expensive and impractical for networks that undergo frequent change. For this reason, automatic calibration techniques have been vigorously researched in recent years. Fully automatic calibration methods depend on the ability to automatically find point correspondences between overlapping views. In typical camera networks, cameras are placed far apart to maximise coverage. This is referred to as a wide base-line scenario. Finding sufficient correspondences for camera calibration in wide base-line scenarios presents a significant challenge. This thesis focuses on developing more effective and efficient techniques for finding correspondences in uncalibrated, wide baseline, multiple-camera scenarios. The project consists of two major areas of work. The first is the development of more effective and efficient view covariant local feature extractors. The second area involves finding methods to extract scene information using the information contained in a limited set of matched affine features. Several novel affine adaptation techniques for salient features have been developed. A method is presented for efficiently computing the discrete scale space primal sketch of local image features. A scale selection method was implemented that makes use of the primal sketch. The primal sketch-based scale selection method has several advantages over the existing methods. It allows greater freedom in how the scale space is sampled, enables more accurate scale selection, is more effective at combining different functions for spatial position and scale selection, and leads to greater computational efficiency. Existing affine adaptation methods make use of the second moment matrix to estimate the local affine shape of local image features. In this thesis, it is shown that the Hessian matrix can be used in a similar way to estimate local feature shape. The Hessian matrix is effective for estimating the shape of blob-like structures, but is less effective for corner structures. It is simpler to compute than the second moment matrix, leading to a significant reduction in computational cost. A wide baseline dense correspondence extraction system, called WiDense, is presented in this thesis. It allows the extraction of large numbers of additional accurate correspondences, given only a few initial putative correspondences. It consists of the following algorithms: An affine region alignment algorithm that ensures accurate alignment between matched features; A method for extracting more matches in the vicinity of a matched pair of affine features, using the alignment information contained in the match; An algorithm for extracting large numbers of highly accurate point correspondences from an aligned pair of feature regions. Experiments show that the correspondences generated by the WiDense system improves the success rate of computing the epipolar geometry of very widely separated views. This new method is successful in many cases where the features produced by the best wide baseline matching algorithms are insufficient for computing the scene geometry.

Researching with the Aboriginal Community, MPH2057- Aboriginal Health Course (Monash University), delivered by the Victorian Aboriginal Community Controlled Health Organisation (VACCHO) & The Burnet Institute at The Burnet Institute, Melbourne, Victoria, 29 September 2010

A copy of the slide presentation titled 'Researching with the Aboriginal Community'. It was presented by Bronwyn Fredericks for the Master of Public Health Program (MPH2057- Aboriginal Health Course) at Monash University. The Monash University Aboriginal Health Course (MPH2057) is delivered in partnership by the Victorian Aboriginal Community Controlled Health Organisation (VACCHO) & The Burnet Institute. The 2010 Aboriginal Health Course was run on Level 3 of The Burnet Institute, 89 Commercial Road, Prahan, Melbourne, Victoria, 29 September 2010.