http://espace.library.uq.edu.au/ The University of Queensland en Fez http://blogs.law.harvard.edu/tech/rss http://espace.library.uq.edu.au/view/UQ:194135 2010-01-28T00:00:00Z O'Brien, Kevin http://espace.library.uq.edu.au/view/UQ:107214 2007-08-24T00:00:00Z Gibbons, S. http://espace.library.uq.edu.au/view/UQ:211173 2010-08-05T00:00:00Z Crane, William http://espace.library.uq.edu.au/view/UQ:186849 2009-11-18T00:00:00Z Farrell, Margaret Ann. http://espace.library.uq.edu.au/view/UQ:158007 2008-11-21T00:00:00Z Martinez-Garcia, Alejandro Nicolas http://espace.library.uq.edu.au/view/UQ:184602 2009-10-07T00:00:00Z Thomas, Catherine M. http://espace.library.uq.edu.au/view/UQ:158247 How can a robot become aware of its surroundings? How does it create its own subjective, inner representation of the real world, so that relationships in the one are reflected in the other? It is well known that structures analogous to Self-Organising Maps (SOM) are involved with this task in animals, and this thesis undertakes to explore if and how a similar approach can be success- fully applied in robotics. In order to study the environment-to-abstraction mapping with a minimum of guidance from directed learning and built-in design assumptions, this thesis examines the active audition task in which a system must determine the direction of a sound source and orient towards it, both in horizontal and vertical direction. Previous explanations of directional hearing in animals, and the implementation of directional hearing algorithms in robots have tended to focus on the two best known directional clues; the intensity and time differences. This thesis hypothesises that it is advantageous to use a synergy of a wider range of metrics, namely the phase and relative intensity difference. A solution to the active audition problem is proposed based on the Parameter- Less Self-Organising Map (PLSOM), a new algorithm also introduced in this thesis. The PLSOM is used to extract patterns from a high-dimensional input space to a low-dimensional output space. In this application the output space is mapped to the correct motor command for turning towards the source and focusing attention on the selected source by filtering unwanted noise. The dimension-reducing capability of the PLSOM enables the use of more than just two directional clues for computation of the direction. This thesis presents the new PLSOM algorithm for SOM training and quantifies its performance relative to the ordinary SOM algorithm. The mathematical correctness of the PLSOM is demonstrated and the properties and some applications of this new algorithm are examined, notably in automatically modelling a robot's surroundings in a functional form: Inverse Kinematics (IK). The IK problem is related in principle to the active audition problem - functional rather than abstract representation of reality - but raises some new questions of how to use this internal representation in planning and execution of movements. The PLSOM is also applied to classification of high-dimensional data and model-free chaotic time series prediction. A variant of Reinforcement Learning based on Q-Learning is devised and tested. This variant solves some problems related to stochastic reward functions. A mathematical proof of correct state-action pairing is devised. 2008-11-21T00:00:00Z Berglund, Erik Johan http://espace.library.uq.edu.au/view/UQ:185182 2009-10-23T00:00:00Z Johnston, Anna http://espace.library.uq.edu.au/view/UQ:185624 2009-11-11T00:00:00Z Blake, Thom W. http://espace.library.uq.edu.au/view/UQ:10603 The use of formal methods in software development seeks to increase our confidence in the resultant system. Their use often requires tool support, so the integrity of a development using formal methods is dependent on the integrity of the tool-set used. Specifically its integrity depends on the theorem prover, since in a typical formal development system the theorem prover is used to establish the validity of the proof obligations incurred by all the steps in the design and refinement process. In this thesis we are concerned with tool-based formal development systems that are used to develop high-integrity software. Since the theorem prover program is a critical part of such a system, it should ideally have been itself formally verified. Unfortunately, most theorem provers are too complex to be verified formally using currently available techniques. An alternative approach, which has many advantages, is to include a proof checker as an extra component in the system, and to certify this. A proof checker is a program which reads and checks the proofs produced by a theorem prover. Proof checkers are inherently simpler than theorem provers, since they only process actual proofs, whereas much of the code of a theorem prover is concerned with searching the space of possible proofs to find the required one. They are also free from all but the simplest user interface concerns, since their input is a proof produced by another program, and their output may be as simple as a `yes/no' reply to the question: Is this a valid proof? plus a list of assumptions on which this judgement is based. When included in a formal development system a stand-alone proof checker is, in one sense, superfluous, since it does not produce any proofs -- the theorem prover does this. Instead its importance is in establishing the integrity of the results of the system -- it provides extra assurance. A proof checker provides extra assurance simply by checking the proofs, since all proofs have then been validated by two independent programs. However a proof checker can provide an extra, and higher, level of assurance if it has been formally verified. In order for formal verification to be feasible the proof checker must be as simple as possible. In turn the simplicity of a proof checker is dependent on the complexity of the data which it processes, that is, the representation of the proofs that it checks. This thesis develops a representation of proofs that is simple and generic. The aim is to produce a generic representation that is applicable to the proofs produced by a variety of theorem provers. Simplicity facilitates verification, while genericity maximises the return on the effort of verification. Using a generic representation places obligations on the theorem provers to produce a proof record in this format. A flexible recorder/translator architecture is proposed which allows proofs to be recorded by existing theorem provers with minimal changes to the original code. The prover is extended with a recorder module whose output is then, if necessary, converted to the generic format by a separate translator program. A formal specification of a checker for proofs recorded in this representation is given. The specification could be used to formally develop a proof-checker, although this step is not taken in this thesis. In addition the characteristics of both the specification and possible implementations are investigated. This is done to assess the size and feasibility of the verification task, and also to confirm that the design is not over-sensitive to the size of proofs. This investigation shows that a checker developed from the specification will be scalable to handle large proofs. To investigate the feasibility of a system based on this architecture, prototype proof recorders were developed for the Ergo 5 and Isabelle 98 theorem provers. In addition a prototype checker was written to check proofs in the proposed format. This prototype is compatible with the formal specification. The combined system was tested successfully using existing proofs for both the Ergo 5 and Isabelle 98 theorem provers. 2004-04-02T00:00:00Z Watson, Geoffrey Norman http://espace.library.uq.edu.au/view/UQ:187778 2009-11-24T00:00:00Z McKay, Judith. http://espace.library.uq.edu.au/view/UQ:193272 2010-01-20T09:35:01Z Jamison, Bryan, 1960- http://espace.library.uq.edu.au/view/UQ:190994 2009-12-24T00:00:00Z Waltisbuhl, Alan Stewart http://espace.library.uq.edu.au/view/UQ:185603 2009-11-10T00:00:00Z Horton, Peter Alan http://espace.library.uq.edu.au/view/UQ:185120 2009-10-21T00:00:00Z Dudley, Robert Peter http://espace.library.uq.edu.au/view/UQ:188996 2009-12-03T00:00:00Z McDonald, Lorna http://espace.library.uq.edu.au/view/UQ:201237 2010-03-30T00:00:00Z Lewis, Glen, 1943- http://espace.library.uq.edu.au/view/UQ:185410 2009-11-03T00:00:00Z Endicott, Michael A. (Michael Ambrose) http://espace.library.uq.edu.au/view/UQ:189954 2009-12-14T00:00:00Z O'Donnell, Fay Margaret http://espace.library.uq.edu.au/view/UQ:189291 2009-12-07T00:00:00Z Buch, Neville Douglas http://espace.library.uq.edu.au/view/UQ:254092 2011-10-04T00:00:00Z Lawson, Ronald Lynton. http://espace.library.uq.edu.au/view/UQ:189000 2009-12-03T00:00:00Z Murray, Louis http://espace.library.uq.edu.au/view/UQ:185518 2009-11-09T00:00:00Z Duncan, Barry James http://espace.library.uq.edu.au/view/UQ:205339 2010-05-19T00:00:00Z Wood, D. H. http://espace.library.uq.edu.au/view/UQ:184936 2009-10-15T00:00:00Z Turner, Kathy http://espace.library.uq.edu.au/view/UQ:245261 2011-08-10T00:00:00Z Pugh-Kitingan, Jacqueline. http://espace.library.uq.edu.au/view/UQ:157921 2008-11-21T00:00:00Z Cameron, David Bruce http://espace.library.uq.edu.au/view/UQ:194126 2010-01-28T00:00:00Z Jensen, Rodney Charles http://espace.library.uq.edu.au/view/UQ:186252 2009-11-16T00:00:00Z Whitford, Michelle Maree http://espace.library.uq.edu.au/view/UQ:9474 This thesis investigates the social and economic factors affecting small-scale forestry development in Leyte Province, the Philippines, and in particular, the potential to use typologies of rural households to aid the description and interpretation of the diversity of households in relation to forestry development. Data for the analysis of the relationships between socioeconomic factors and tree management behaviour and intentions and the construction of a typology of rural households in Leyte was gathered from four case study communities on the Island. Following focus group discussions in each of the participating communities to gather background data and populate the structured interview schedule, representative samples of 50 households were selected and interviewed in each of the four communities. Analysis of the present tree management activities of households in the four communities revealed that most households surveyed (approximately 80%) indicated that they are presently managing at least a few trees, the primary purpose of most tree management activities being to supply timber for the households' own needs. Only 10% of respondents indicated that they intend to sell trees they are presently managing, and 25% stated that they intend to plant and manage trees for the production of timber for sale in the future. Approximately 60% of responding households indicated an interest in developing commercial tree farming on the land they manage. Thus it is concluded that small-scale commercial tree growing is uncommon in the communities involved in the survey, and that many households are interested in developing their tree planting and management activities but feel constrained from participation by various factors. The first level of exploration of the socioeconomic factors affecting rural households' tree management behaviour involved univariate analyses of the relationships between households' tree management behaviour and intentions, their socioeconomic characteristics and their attitudes to forestry. The level of resources controlled by the household, in terms of the area of the land managed by the household, their tenurial security and their cash income, are correlated with higher levels of participation in forestry activities, and greater intentions to plant higher numbers of trees in the future. Some farming system variables are also related to higher levels of tree planting and management activity, including the management of livestock and of farm plots distant from their house. While control over higher than average levels of productive resources are, in general, positively correlated to the active management of trees on their land, there are patterns of exceptions to this trend. The exploration of the interrelationships between socioeconomic factors and attitudes affecting households' tree management behaviour was undertaken through the definition of a typology of rural households in relation to forestry. Five types were defined, each having different attitudes to forestry activities. The interpretation of the types was undertaken by describing and comparing the socioeconomic and behavioural characteristics of the types in the typology. The types were characterised by differences in their control of productive resources, differences in their present and intended levels and types of forestry activity, and by differences in their participation in training activities run by development programs. The characteristics of the types were found to correspond highly with descriptions of the socioeconomic factors affecting forestry activities of smallholder households reported by previous studies into and theories about the socioeconomic factors affecting smallholder forestry development. The typology of rural households does help to describe and interpret the variation within each of the four communities in terms of households' attitudes to forestry development and their socioeconomic characteristics. It is concluded that these variations between households mean that the various types of households will be affected in different ways by forestry development programs. It is also concluded that the present state of forestry policies and the market for timber products is such that substantial increase in the level of forestry activity by smallholders is unlikely without comprehensive land use planning, policy reform in regards to tree registration and transport permits, and market development. Recommendations for further research and policy development arising from the thesis focuses on the need to create enabling conditions in which forestry activities can occur and on ways to address the differing needs of the various types defined in the typology. 2005-07-15T00:00:00Z Emtage, Nicholas F. http://espace.library.uq.edu.au/view/UQ:186245 2009-11-16T00:00:00Z Walters, Ian Noel http://espace.library.uq.edu.au/view/UQ:190069 2009-12-15T00:00:00Z Bletchly, Cheryl. http://espace.library.uq.edu.au/view/UQ:187785 Innovation is an imperative in all industry sectors. For those such as construction, which are not considered high-tech and which operate as one-off projects, the uptake and diffusion of new innovations into ongoing practice across projects pose particular problems. The nature of these problems faced at a project level needs to be better understood. This thesis is an exploration of innovation implementation in the context of Project-Based Engineering (PBE). It is an empirical investigation of how new planning technologies are implemented in major infrastructure construction projects and the barriers that prevent such implementations from being effective. The findings of this investigation are used to develop and evaluate a new model of innovation implementation in this context. The research design is centred on the immersion of a participant-observer in seven live construction projects over a period of 3.5 years. Each project studied was implementing the same innovation: 4D CAD modelling (3D design model + the construction schedule). A wide cross-section of data was gathered in the field including direct observations, documents and other work products from participation, email and other correspondence associated with the 4D CAD implementations, and formal and informal discussions with project-participants. These data were analysed using content analysis software to find patterns. The research was iterative and involved three phases. The initial phase was a pilot study of implementation in practice using the data from one project. It produced rich descriptions of what transpired and a critical comparison with accounts from the literature. This led to a series of propositions about the influence of project-participant perceptions that were synthesised into a new theoretical model: the initial Perception-Influence model (P-I1 model). The middle research phase then developed this model iteratively using a more-focused data collection and content analysis across four construction project organisations. This was done to provide supporting evidence for the theoretical constructs in the P-I1 model as well as to refine them and add new ones. The outcomes of the middle phase were the P-I2 and P-I3 models. The final research phase analysed the data from the last two project organisations in terms of the P-I model framework with a view to evaluating the model’s theoretical significance and practical applications. The P-I model shows that negative perceptions of value, benefit and usability can cause an innovation implementation to be ineffective as a result of discontinued use or neglect. It provides a map for the progression of an implementation using the perceptions and actions of project-participants as primary constructs. The model proposes that each perception is formed by a number of contributing factors or secondary constructs synthesised from implementation research and user acceptance literature, for example, an opinion or concern about how much an innovation costs (i.e. transaction costs). It also proposes that each perception has both a positive and negative associated action. The constructs that make up the P-I model are grounded in the empirical data. This is because the actions, opinions and concerns of project-participants observed in live projects are evident in project documentation such as emails. These two sources (i.e. observations and project documentation) provide data sets that were used to triangulate inferences about the perceptions of project-participants and the outcome of each 4D CAD implementation (i.e. effective or otherwise). This aspect of the research was not only important for the recommendation of potential applications for the P-I model but also during its conception, development and evaluation. The P-I model is a new and important perspective for both implementation research and PBE practitioners. It helps satisfy the calls for studies of innovation implementation that focus on factors at an individual level and those asking for a better understanding of innovative behaviour. This work shows PBE practitioners how the perceptions of project-participants can have a major impact on the effectiveness of an innovation implementation. The findings provide an evidential basis that can improve implementation effectiveness, especially in PBE organisations. The knowledge built into the P-I model can also assist the planning and execution of innovation implementation strategies, aid in the assessment and redirection of those in progress, and help document lessons learned for implementations within project organisations that have been previously completed. This research uses the P-I model to open the way for future empirical studies of innovation implementation in PBE contexts beyond construction. These would also provide data to further refine the constructs in the model. 2009-11-24T00:00:00Z Miller, Andrew http://espace.library.uq.edu.au/view/UQ:186851 2009-11-18T00:00:00Z Melrose, Craig http://espace.library.uq.edu.au/view/UQ:192541 2010-01-14T00:00:00Z Ward, Nigel Thomas Edgar http://espace.library.uq.edu.au/view/UQ:185756 2009-11-12T00:00:00Z Siemon, Rosamond http://espace.library.uq.edu.au/view/UQ:189765 2009-12-11T00:00:00Z Thorpe, Bill http://espace.library.uq.edu.au/view/UQ:105703 2007-08-24T00:00:00Z Cumming-Potvin, Wendy M. http://espace.library.uq.edu.au/view/UQ:204518 2010-04-28T00:00:00Z David, Bruno, 1962- http://espace.library.uq.edu.au/view/UQ:190060 2009-12-15T00:00:00Z Switala, John http://espace.library.uq.edu.au/view/UQ:189266 2009-12-07T00:00:00Z Divett, Neil Graham http://espace.library.uq.edu.au/view/UQ:193258 2010-01-20T00:00:00Z Johns, Gary Thomas http://espace.library.uq.edu.au/view/UQ:192266 2010-01-12T00:00:00Z Hall, Allen Harry http://espace.library.uq.edu.au/view/UQ:205341 2010-05-19T00:00:00Z De Gruchy, Graham Francis http://espace.library.uq.edu.au/view/UQ:194993 2010-02-09T00:00:00Z Humphrey, Michael D. (Michael David), 1946- http://espace.library.uq.edu.au/view/UQ:157992 Baculoviruses are lytic insect viruses. Upon internalisation, the viral genome orchestrates a sequential expression process ultimately leading to lysis of the infected cell. Release of progeny capable of infecting other cells during the process completes the infection cycle. Studies of the infection cycle in cell culture are typically conducted by synchronous infection, i.e. near simultaneous infection of all cells, by means of high virus concentrations. The behaviour of the synchronously infected culture, such as the timing of onset of progeny release, is considered representative for the infection progression within individual cells. In reality, however, the synchronously infected culture only reflects the average behaviour of all infected cells. The infection progresses in individual cells display large variability; this is most obvious in the observation that within the same culture some cells undergo cell lysis at two days post infection while others remain viable up to four days post infection. Such variabilities or asynchronies observed in synchronously infected culture is the topic of this thesis. Using a simple phenomenological model, it is demonstrated that cell death and associated intracellular product release is adequately described assuming that the waiting time from infection to cell death follows a Gaussian distribution with a mean of 59 hours post infection (hpi) and a standard deviation of 15hpi. Unlike other deterministic model developed over the last decade (Licari and Bailey 1992; Nielsen 2000), this stochastic model does not make the biologically inconsistent assumption that cells continue to be metabolically active following loss of membrane integrity. While elegant in its simplicity, the model provides no explanation for the underlying stochasticity. Investigations into the cause of this dispersion of cell death highlighted further asynchronies in the specific recombinant protein yield, in viral DNA content, in virus budding rate, and in cell volume increase instead of clarifying the issue. A modelling framework developed by Licari & Bailey (1992) and later Hu & Bentley (2000) incorporates the number of infectious particles each individual cell receives as a possible source of the dispersions in the host cell responses. However, this was found NOT to be the cause of the observed asynchronies under non-substrate limiting conditions. The timing of cell death, cell volume increase, recombinant product yield, viral DNA content, and virus budding rate is identical in Sf9 cell cultures infected at multiplicities of infection of ~5, ~15, and ~45 infectious particles per cell. Cell cycle variation has previously been suggested as a possible cause for observed asynchronies in baculovirus infections (Brown and Faulkner, 1975). The cell cycle phase is indirectly linked to the cell volume, because a G2-phase cell prior to division is inherently twice the cell volume of a G1-phase cell after cell division. By the same logic, it is also apparent that a G2-phase cell possesses twice the number of ribosomes of a G1-phase cell and thus a doubled protein production capacity. The effect of the cell cycle or cell volume on the baculovirus infection was determined by splitting an exponentially growing Sf9 cell culture into 5 cell size dependent fractions by centrifugal elutriation. The subsequent infection of these fractions showed (1) no dependency of the timing of cell lysis and cell volume increase and (2) approximately twofold increase of a) recombinant protein yield, b) viral DNA concentration, and c) budded virus yield. The recombinant protein yield showed a strong proportionality to the initial cell volume and the total RNA concentration during the late phase of the infection. As argued in chapter 6, these proportionalities suggest that the observed differences in the responses of the cell fractions to the baculovirus infection are more likely caused by the difference in the protein production capacity than by cell cycle specific molecules. This investigation gave also reason to speculate that infected cells cannot progress beyond the G2/M phase, and cell cycle progression continues undisturbed until ~8hpi when all cellular DNA replication appears to cease. Resuspended, infected Sf9 cells synchronised by centrifugal elutriation showed an identical cell cycle distribution as the non-infected control cultures for the first ~8hpi; G1 and G2/M phase cell proportions remained unchanged, whereas S phase cells progress to G2/M phase. Subsequently, the non-infected control cells resumed normal cycling whereas all infected cells remained at the same cell cycle phase from 8 to 11hpi. The initial cell cycle arrests in G2/M phase in both infected and non-infected cultures were caused through medium exchange. 2008-11-21T00:00:00Z Haas, Richard http://espace.library.uq.edu.au/view/UQ:186803 2009-11-17T00:00:00Z Maxwell, Graham Samuel. http://espace.library.uq.edu.au/view/UQ:260202 This dissertation proposes an original contribution to knowledge in two ways. First, it proposes that journalism can enable fiction. It also does so through methodology used to test that proposition. This is in the form of the Journalist-Novelist Analytical Model (JNAM). In considering journalists who become novelists, the study explores how forms of writing in journalism and fiction relate to and influence each other. Five Australian novelists are used as case studies in identifying journalism’s impacts on fiction. They are: Marcus Clarke; George Johnston; Olga Masters; Susan Johnson; and Robert Drewe. Print journalism is the focus of the thesis. However, newspaper and magazine journalism share important characteristics with broadcast journalism such as storytelling, news judgment and interaction with people, issues and events of public concern. This thesis asks two inter-related questions. First, it considers why so many journalists have written novels. Second, it explores whether journalism can enable fiction. From 1830, when Australia’s first novel by former convict Hugh Savery was published, to 2003 nearly 300 novelists have performed journalistic work. This journalism-fiction nexus is mirrored in the United Kingdom and in the United States, where Fedler (2000: 226) speculates "hundreds or even thousands" of novelists started as reporters. In seeking answers to the two core questions, five research questions are proposed. They ask whether novelists who have worked journalistically are likely to: 1. have been practised writers who have obtained payment for forms of writing other than in journalism and fiction; 2. base their fiction on experience and direct observation rather than imagination; 3. produce readable prose in fiction because of their journalistic focus on what is perceived to appeal to most readers; 4. have been attracted to fiction as a method of self-expression journalism could not satisfy; 5. be seen by publishers as potential novelists because of their media contacts and experience and public profiles as journalists. These research questions are tested through: 1. a survey of novelists with journalistic experience; 2. interviews with journalist-novelists; 3. a readability study involving 20 novelists and 60 novels; 4. a creativity study involving 16 journalism students tested over 10 weeks; 5. the three-tier JNAM that examines the origins and development of newspapers and novels from 1850 to 2002; 6. quantitative listings of fiction writers with journalistic experience; 7. an examination of 16 exemplary texts; and 8. five case studies focussing on exemplary authors’ journalism and fiction. The dissertation is presented in three sections. The first provides an historical overview of newspapers and novels, from England in the 18th century to Australia from 1850 to 2002. Through the JNAM it identifies overlapping cultural, economic and technological influences that shaped the practices of journalists and novelists and the functions of newspapers and novels. The second section addresses occupational issues in journalism that inform transitions to other writing forms. The final section has chapters on the exemplary novelists. The thesis concludes that journalism, with significant qualifications, can enable fiction. 2011-11-02T00:00:00Z Conley, David http://espace.library.uq.edu.au/view/UQ:188122 2009-11-27T00:00:00Z Hardy, Anne http://espace.library.uq.edu.au/view/UQ:198457 2010-03-09T00:00:00Z Hopkins-Weise, Jeffrey Ellis