Infrastructure Engineering - Theses
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ItemTrip quality in peer-to-peer shared ride systems( 2007-01)In a peer-to-peer shared ride system, transportation clients with traffic demand negotiate with transportation hosts offering shared ride services for ad-hoc ridesharing in a continuously changing environment, using wireless geosensor networks. Due to the distinctive characteristic of this system—a complex and non-deterministic transportation network, and a local peer-to-peer communication strategy—clients will always have limited transportation knowledge, both from a spatial and a temporal perspective. Clients hear only from nearby hosts, and they do not know the future availability of current or new hosts. Clients can plan optimal trips prior to departure according to their current knowledge, but it is unlikely that these trips will be final optimal trip due to continuously changing traffic conditions. Therefore, it is necessary to evaluate the trip quality in this dynamic environment in order to assess different communication and wayfinding strategies. (For complete abstract open document)
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ItemA rigorous approach to the technical implementation of legally defined marine boundaries( 2007)The management and administration of legally defined marine boundaries in Australia is subject to a variety of political, legal and technical challenges. The purpose of this thesis is to address three of the technical challenges faced in the implementation of marine boundaries which cannot be dealt with by applying conventional land cadastre and land administration principles. The three challenges that are identified and addressed are (i) marine boundary delimitation and positioning uncertainty, (ii) the construction and maintenance of four dimensional marine parcels, and (iii) the modelling and management of marine boundary uncertainty metadata.
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ItemDamage identification and condition assessment of civil engineering structures through response measurement( 2007-04)This research study presents a new vibration-based non-destructive global structural damage identification and condition monitoring technique that can be used for detection, localization and quantification of damage. A two-stage damage identification process that combines non-model based and model-based damage identification approaches is proposed to overcome the main difficulties associated with the solution of structural damage identification problems. In the first stage, performance assessment of various response parameters obtained from the time-domain, frequency-domain and spectral-domain analysis is conducted using a non model-based damage detection and localization approach. In addition, vibration response parameters that are sensitive to local and global damage and that possess strong physical relationships with key structural dynamic properties are identified. Moreover, in order to overcome the difficulties associated with damage identification in the presence of structural nonlinearity and response nonstationarity, a wavelet transform based damage-sensitive parameter is presented for detection and localization of damage in the space domain. The level of sensitivity and effectiveness of these parameters for detection and localization of damage are demonstrated using various numerical experimental data determined from one-dimensional and two-dimensional plate-like structures.
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ItemDestination descriptions in urban environments( 2007-04)An important difference exists between the way humans communicate route knowledge and the turn-by-turn route directions provided by the majority of current navigation services. Navigation services present route directions with the same amount of detail regardless the route segment’s significance in the instructions, user’s distance from the destination, and finally the level of user’s familiarity with particular parts of the environment. (For complete abstract open document)
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ItemSensor orientation in image sequence analysis( 2007-06)This work investigates the process of automating reconstruction of buildings from video imagery. New metrics were developed to detect the least blurred images in a sequence for further processing. Phase correlation for point matching was investigated and new metrics were developed to identify successful matches. Direct relative orientation algorithms were investigated in-depth. A significant finding was a new 6-point algorithm which outperformed previously published algorithms for a number of calibrated camera and target geometries. The development of the new metrics and the outcomes from the comprehensive investigations conducted have contributed to a better understanding of the challenging problem of automatically reconstructing 3D objects from image sequences.
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ItemMultiple geo-visualisations for the enhanced comprehension of land cover changes( 2007)This research explores multiple geo-visualisations to enhance the comprehension of changing reality. It establishes a cognitive visualisation model as a framework and a multiple visualisation approach for implementation. Multiple visualisations of land cover changes including 2D and 3D, abstract and realistic simulations with static and dynamic components are created and tested through a formal user survey. It is concluded that although the real world cannot be perfectly represented, comprehension and interpretation can be improved and enhanced by providing effective multiple visualisations in accordance with users’ specific needs and tasks.
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ItemAgent behavior in peer-to-peer shared ride systems( 2007-01)Shared ride systems match the travel demand of transport a client with the supply of vehicles, or hosts, so that the client find rides to their destinations. A peer-to-peer shared ride system allows a client to find rides in an ad-hoc manner, by negotiating directly with nearby hosts via radio-based communication. Such a peer-to-peer shared ride system has to deal with various types of hosts, such as private cars, taxicabs and mass transit vehicles. Agents, i.e. a client and hosts, have diverse behaviors in such systems. Their different behaviors affect the negotiation process, and consequently the travel choices. Preliminary research (Winter et al. 2005) has investigated peer-to-peer shared ride systems with homogeneous hosts and immobile client. This thesis extends their work to multiple types of agents. It focuses on what are typical agent behaviors in peer-to-peer shared ride systems, and how these behaviors affect negotiation processes in a dynamic transport environment. (For complete abstract open document)
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ItemAutomated methods in digital close range photogrammetry( 2007)Digital close-range photogrammetry has traditionally been associated with expensive, metric, non-colour digital cameras, rather than with low-cost, non-metric, colour consumer-grade cameras. While off-the-shelf cameras have offered their potential for use for a variety of low- to medium-accuracy measurement tasks, their application has been limited for a number of technical reasons. The aim of the research undertaken for this PhD has been to develop the mathematical models, algorithms, computational procedures and operational methodologies necessary to facilitate metric application of consumer-grade cameras. Notable developments achieved within the research include colour image scanning; a new colour coded target strategy for automated exterior orientation; innovations in the computational process for relative orientation; automated camera calibration; and improvements in algorithms for automatic network formation and orientation for vision metrology. Following a brief overview of consumer grade digital cameras, along with an account of initial image processing research to support digital image rectification, the thesis presents a fast and fully automated algorithm for scanning and target detection for colour imagery. Colour is then also exploited in the design of a new photogrammetric coded target system, which facilitates automatic homologous point determination in multi-image networks. The development of a Monte Carlo style approach to initial value determination for coplanarity-based relative orientation is then presented. This removes the need for existing object space coordinate information, such as an exterior orientation device. A new system for fully automatic colour digital camera calibration via the new colour-coded targets and a modified self-calibrating bundle adjustment technique is then discussed. The culmination of the research project lies in the development of a state-of-the-art fully automatic photogrammetric network orientation system which supports a new algorithm for image point correspondence determination and thus automatic detection and subsequent triangulation of targeted object feature points. The new system, which is detailed in Chapter 7 and which utilizes a further colour coded target scheme, broadens the potential of automated close-range photogrammetry across a range of application areas, from traffic accident reconstruction to high-precision industrial metrology.
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ItemEnhanced value for money outcomes through alliance techniques: a framework for public private partnerships in Australia( 2007)While much of Australia's current infrastructure has been traditionally provided by the public sector, there is a recent trend towards private organisations providing infrastructure services. Governments have realised that to maintain economic competitiveness along with social cohesion, the value of private finance within infrastructure development can not be understated, whereby the private sector invests in infrastructure and provides related services to the public sector at a reasonable cost. Whilst there are a multitude of variations, this concept is commonly known as a Public Private Partnership (PPP). Recent Public Private Partnership projects in the developed world have focussed heavily on achieving Value for Money (VfM) outcomes for governments through the application of robust polices and guidelines. This study has investigated current Australian PPP policies (both State and Federal) to determine whether enhanced Value for Money outcomes can be achieved through the integration of Alliance techniques. Value for Money in a theoretical sense is defined as the functional performance achieved for a given consumption of resources. The actual quantum of Value for Money calculated is not important; the focus being on the relativity between the traditional PPP model and a model that utilises Alliance techniques. Specific techniques and perceptions of Alliance Contracting were investigated through a series of surveys with direct users from both the public and private sectors, and the level of applicability to a PPP process was established. A detailed review of Australian and UK PPP projects was undertaken and a series of in depth case studies were investigated to better understand the practical implications and the current shortcomings in current PPP policy approaches. The framework for a new approach was developed and further tested and refined through an industry workshop with key PPP representatives from a variety of sectors. The study concludes with drafting new guidelines for PPP projects, to enhance Value for Money outcomes for all parties. Whilst it was found that not all Alliance techniques would enhance Value for Money outcomes, a number of key areas were identified where improvements could be made to current practices, namely: • Development of policies to mandate interaction between the State, bidders and end users at critical stages of PPP projects. Proposed enhancements to the current PPP policy model have been developed, including: • Incorporation of relationship based Alliancing techniques to assist with the complex and varied contractual nature of a PPP project; • A credit based abatement regime which incentivises parties to outperform specific outputs in the form of credits which can then be used against underperforming areas; and • The appointment of an Independent Reviewer to oversee the long term management of the contract.
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ItemProperty rights, restrictions, and responsibilities: their nature, design, and management( 2007)This research is composed of four broad sections: introduction, background, research and conclusions. The introductory phase describes the research problem and aim. It asserts that property rights, restrictions and responsibilities over land are designed and administered in a disparate, ad hoc and disorganized fashion which makes achieving sustainable development objectives difficult, if not impossible. This thesis aims to develop a framework for organizing the management of property rights, restrictions and responsibilities in a way that enables the achievement of sustainable development objectives by citizens and governments. The background section explores the problem more deeply. First, it looks back to the root causes: a diverse range of drivers including environmentalism, free market economies and social equity are producing legislative and policy sprawl. Second, it looks at the limitations of current attempts to overcome the problem: traditional land administration tools are being bypassed, small ad hoc legal and technical solutions are favoured and only limited holistic approaches exist. Third, the background section investigates the emerging tools being applied to the problem: ontological design, social learning, SDI and spatial technologies, uncertainty theory and new funding models could all profoundly influence the management of land interests. The research section uses the contextual understanding to develop, justify and execute a robust research design. The hypothesis articulates that expanding the existing land administration systems with new tools and principles would enable better management of property rights, restrictions and responsibilities and consequently assist the achievement of sustainable development objectives by citizens and government. A mixed methodology involving both qualitative and quantitative studies is required to test the hypothesis. Additionally, top-down (government) and bottom-up (parcel) perspectives are also used. The sheer size of the legislative sprawl (Federal – 514 statutes, State – 620 statutes, Local – 7 statutes) and the administrative effort required to manage it is exposed at all levels of government. However, amongst the tangle of bureaucracy, pockets of very well managed, automated and spatially integrated land interests is uncovered. Additionally, the underutilized potential of the cadastre and existing registry to manage ‘some’ interests is identified. The bottom-up case studies provide a detailed insight into the effect of old and new land interests on individual parcels. The historical complexities of existing cadastral and registration systems and their deficiencies are also clear. Together, the results from these equally weighted case studies are used to test the appropriateness of the hypothesis, and generate components of an updated land administration toolbox, one capable of managing all interests in land. The conclusions section synthesizes the results and develops the ‘RRR Toolbox’ and ‘Property Object’ concept. The ‘RRR Toolbox’ includes eight components: policy, legal, tenure, institutional, cadastral and registration, spatial and technology, capacity and emerging tools. If a jurisdiction wishes to coherently manage its land rights, restrictions and responsibilities, then each of the eight components needs to be addressed and acted upon. The ‘Property Object’ is defined as an advanced descriptive framework of the key attributes (objective, action, spatial extent, people impacted, duration) that make up an individual property interest. The property object permits holistic treatment of all property interests, from ownership down to simple access powers, and also enables meaningful contrast between different interests. Together, the ‘RRR Toolbox’ and ‘Property Object’ provide new and innovative perspectives on the research aim. The results of the case studies reveal the hypothesis to be a point of truth. Together the concepts help to deliver sustainability objectives. However, this thesis does not claim to fully solve the problem: more work on each of the toolbox components and their implementation in different jurisdictions identified is required.