Semantic manipulation and business context in big data analytics
- Authors: Dinh, Loan
- Date: 2018
- Type: Text , Thesis , PhD
- Full Text:
- Description: Business organisations receive a huge amount of data from many sources every day. These data are known as big data. Since they are mostly unstructured, big data creates a complex problem of how to capture, manage, analyse and then derive meaningful information from them. To deal with the challenges that big data has brought, this research proposes a new technique in big data analytics in the business area to integrate semantically meaningful information relevant to textual queries and business context. To achieve this aim, this study makes three major related contributions. Firstly, the relationship between business processes and strategies is established using the concept of a rule-based inference model via facts and annotations. This relationship is required to determine the importance of a big data query for a business organisation. Secondly, we introduce approaches to determine the significance level of a query, by incorporating the processstrategy relationship, process contributions and priority of business strategies. Thirdly, the proposed data analytic technique embeds business context into the bedrock of data collection and analysis process. The first two contributions were implemented using Python programming language including the Pyke package (Pyke is built in the Python environment and has an artificial intelligence tool for the development of expert systems) and their performances were analysed based on a business use case. The last contribution was implemented mainly in the Hadoop and Java programs. Results show that the first contribution successfully establishes the processstrategy relationship, the second calculates the significance level of a query in relation to a business organisation, while the third reveals the huge impact of query significance level and business context on big data collection and captures deep business insights.
- Description: Doctor of Philosophy
- Authors: Dinh, Loan
- Date: 2018
- Type: Text , Thesis , PhD
- Full Text:
- Description: Business organisations receive a huge amount of data from many sources every day. These data are known as big data. Since they are mostly unstructured, big data creates a complex problem of how to capture, manage, analyse and then derive meaningful information from them. To deal with the challenges that big data has brought, this research proposes a new technique in big data analytics in the business area to integrate semantically meaningful information relevant to textual queries and business context. To achieve this aim, this study makes three major related contributions. Firstly, the relationship between business processes and strategies is established using the concept of a rule-based inference model via facts and annotations. This relationship is required to determine the importance of a big data query for a business organisation. Secondly, we introduce approaches to determine the significance level of a query, by incorporating the processstrategy relationship, process contributions and priority of business strategies. Thirdly, the proposed data analytic technique embeds business context into the bedrock of data collection and analysis process. The first two contributions were implemented using Python programming language including the Pyke package (Pyke is built in the Python environment and has an artificial intelligence tool for the development of expert systems) and their performances were analysed based on a business use case. The last contribution was implemented mainly in the Hadoop and Java programs. Results show that the first contribution successfully establishes the processstrategy relationship, the second calculates the significance level of a query in relation to a business organisation, while the third reveals the huge impact of query significance level and business context on big data collection and captures deep business insights.
- Description: Doctor of Philosophy
'And for harmony most ardently we long' : Musical life in Ballarat, 1851-1871
- Authors: Doggett, Anne
- Date: 2006
- Type: Text , Thesis , PhD
- Full Text:
- Description: "The study examines two decades in the musical life of Ballarat, a regional city in south-eastern Australia. Beginning at the time of the 1851 gold rush, it covers the period in which Ballarat grew from a rough mining camp to an established city with a socially and ethnically diverse population of over 40,000 people. The thesis pursues the aim of looking at the music practices of the community in ways that will further our understanding of the significance of music in the lives of the people."--Abstract.
- Description: Doctor of Philosphy
- Authors: Doggett, Anne
- Date: 2006
- Type: Text , Thesis , PhD
- Full Text:
- Description: "The study examines two decades in the musical life of Ballarat, a regional city in south-eastern Australia. Beginning at the time of the 1851 gold rush, it covers the period in which Ballarat grew from a rough mining camp to an established city with a socially and ethnically diverse population of over 40,000 people. The thesis pursues the aim of looking at the music practices of the community in ways that will further our understanding of the significance of music in the lives of the people."--Abstract.
- Description: Doctor of Philosphy
Reflective space : A personal journey towards a re-envisioning of the Australian landscape
- Authors: Donald, Colin
- Date: 2008
- Type: Text , Thesis , PhD
- Full Text:
- Description: Whilst the notion of the ‘Reflective Space’ could arguably encompass many conceptual positions and propositions, for the purposes of this research investigation the ‘Reflective Space’ referred to in the title of this exegesis will focus upon what I consider as an emerging and growing consciousness of the natural world. As a theoretical and conceptual construct, the investigation considers how this growing consciousness can be seen to be expressed through the medium of representations of the Australian landscape. This work considers a number of contemporary theoretical positions and a number of relevant social and political questions; it also acknowledges that within such spheres of reflection, the issue of being sustainable in relation to our interactions and perceptions of this natural world looms as perhaps one of the most pressing of our time. While it will be acknowledged that the depiction of landscape enjoys a long-standing tradition within the Australian cultural mind, the suggestion will be made that certain aspects of these visualisations can be seen to be ‘reflective’ of a visual, cultural and physical degradation, and indeed even an apprehension of the physical ‘space’ that is represented as landscape. The investigation considers and reflects upon what can be observed as contentious and ambivalent attitudes expressed towards landscape perceived through works of art. Strategies for adopting a perceptual visual ethic grounded within the concepts and principles of sustainability will be presented for consideration. By applying such modes of interpretation to perceptions of land and landscape depiction, new appreciations for the cultural ‘space’ that is landscape will be developed. Such understandings will consider and reflect upon the temporal nature of our natural world. The thesis is this: that to be able to think and act in a sustainable fashion in relation to our environment, our perceptions and interpretations of visualisations of landscape must include a recognition that the land is a ‘temporal’ space, in which past and possible futures are immanent in the present.
- Description: PhD (Visual Arts)
- Authors: Donald, Colin
- Date: 2008
- Type: Text , Thesis , PhD
- Full Text:
- Description: Whilst the notion of the ‘Reflective Space’ could arguably encompass many conceptual positions and propositions, for the purposes of this research investigation the ‘Reflective Space’ referred to in the title of this exegesis will focus upon what I consider as an emerging and growing consciousness of the natural world. As a theoretical and conceptual construct, the investigation considers how this growing consciousness can be seen to be expressed through the medium of representations of the Australian landscape. This work considers a number of contemporary theoretical positions and a number of relevant social and political questions; it also acknowledges that within such spheres of reflection, the issue of being sustainable in relation to our interactions and perceptions of this natural world looms as perhaps one of the most pressing of our time. While it will be acknowledged that the depiction of landscape enjoys a long-standing tradition within the Australian cultural mind, the suggestion will be made that certain aspects of these visualisations can be seen to be ‘reflective’ of a visual, cultural and physical degradation, and indeed even an apprehension of the physical ‘space’ that is represented as landscape. The investigation considers and reflects upon what can be observed as contentious and ambivalent attitudes expressed towards landscape perceived through works of art. Strategies for adopting a perceptual visual ethic grounded within the concepts and principles of sustainability will be presented for consideration. By applying such modes of interpretation to perceptions of land and landscape depiction, new appreciations for the cultural ‘space’ that is landscape will be developed. Such understandings will consider and reflect upon the temporal nature of our natural world. The thesis is this: that to be able to think and act in a sustainable fashion in relation to our environment, our perceptions and interpretations of visualisations of landscape must include a recognition that the land is a ‘temporal’ space, in which past and possible futures are immanent in the present.
- Description: PhD (Visual Arts)
"Working through it" : men's experiences of fatherhood following a life event / Allan H. Donelly
- Authors: Donelly, Allan H.
- Date: 2004
- Type: Text , Thesis , PhD
- Full Text:
- Description: "This study set out to determine if and how men change their approach to fatherhood for reasons other than those prescribed by society, that is, are fathers capable of change for personal and interpersonal reasons. ... The participants needed to have experienced a life event whist being a father."
- Description: Doctor of Philosophy
- Authors: Donelly, Allan H.
- Date: 2004
- Type: Text , Thesis , PhD
- Full Text:
- Description: "This study set out to determine if and how men change their approach to fatherhood for reasons other than those prescribed by society, that is, are fathers capable of change for personal and interpersonal reasons. ... The participants needed to have experienced a life event whist being a father."
- Description: Doctor of Philosophy
Contrasting colonial collectors: an examination of nineteenth-century collectors of Victorian Indigenous cultural artefacts, violence and antiquarianism
- Authors: Donovan, Paul
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text:
- Description: The motivations and methodologies for collecting Indigenous Australian cultural material from colonial Victoria from 1802–1900 have varied widely. Some collectors enacted frontier war to disarm a colonised people and dispossess them of their land. Others sought to salvage a material scientific record of the culture of a race they believed was doomed to imminent extinction or build museum collections for public education. Some sought souvenirs or gifts to document tourism experiences, and some acquired exotic material for commercial enterprise. This dissertation offers a historical overview of political and scientific paradigms underpinning the collection of Indigenous Australian cultural material from nineteenth-century Victoria and characterises the resulting collecting practices. The nature of the collection methods and the content of the collections were examined. The dynamics of relationships between nineteenth-century collectors, Indigenous Australian communities, the source of collections, and collecting institutions were analysed following on from Nicholas Thomas’s entangled objects framework and using the methodologies of Geertz’s thick description, McBryde’s ethnohistory, Denzin’s interpretive biography and Thomas, Znaniecki and Shaw’s biographical analysis. By examining evidence in the primary sources of Indigenous Australian value for colonial material and colonial value of Indigenous material, this dissertation deconstructed the nature of the relationships between agents. It explored the nexus between objects, institutions and individuals. The case studies add depth to the understanding of the collections of Victorian cultural material still held in museums.
- Description: Doctor of Philosophy
- Authors: Donovan, Paul
- Date: 2023
- Type: Text , Thesis , PhD
- Full Text:
- Description: The motivations and methodologies for collecting Indigenous Australian cultural material from colonial Victoria from 1802–1900 have varied widely. Some collectors enacted frontier war to disarm a colonised people and dispossess them of their land. Others sought to salvage a material scientific record of the culture of a race they believed was doomed to imminent extinction or build museum collections for public education. Some sought souvenirs or gifts to document tourism experiences, and some acquired exotic material for commercial enterprise. This dissertation offers a historical overview of political and scientific paradigms underpinning the collection of Indigenous Australian cultural material from nineteenth-century Victoria and characterises the resulting collecting practices. The nature of the collection methods and the content of the collections were examined. The dynamics of relationships between nineteenth-century collectors, Indigenous Australian communities, the source of collections, and collecting institutions were analysed following on from Nicholas Thomas’s entangled objects framework and using the methodologies of Geertz’s thick description, McBryde’s ethnohistory, Denzin’s interpretive biography and Thomas, Znaniecki and Shaw’s biographical analysis. By examining evidence in the primary sources of Indigenous Australian value for colonial material and colonial value of Indigenous material, this dissertation deconstructed the nature of the relationships between agents. It explored the nexus between objects, institutions and individuals. The case studies add depth to the understanding of the collections of Victorian cultural material still held in museums.
- Description: Doctor of Philosophy
The invisible contract : care-giving in home-based rehabilitation
- Authors: Dow, Briony
- Date: 2003
- Type: Text , Thesis , PhD
- Full Text:
- Description: This study took a critical feminist approach to the analysis of family care-giving in home-based rehabilitation in Victoria, Australia.
- Description: Doctor of Philosophy
- Authors: Dow, Briony
- Date: 2003
- Type: Text , Thesis , PhD
- Full Text:
- Description: This study took a critical feminist approach to the analysis of family care-giving in home-based rehabilitation in Victoria, Australia.
- Description: Doctor of Philosophy
Learning in community and life in community" : the concept of a community as a classroom
- Authors: Downey, Tamara
- Date: 2002
- Type: Text , Thesis , PhD
- Full Text:
- Description: This thesis presents the Leigh community’s view of the impact of Hayden College on Leigh. The study establishes ‘community’ as the key aspect of this atypical school-community partnership in the context of research which shows that effective school-community partnerships are socially and economically beneficial for rural communities. The research question addresses the relationship between a particular college and a specific community. Hayden College was attracted to life in Leigh as a source of learning for its students and to community life in Leigh in particular. The research demonstrates that the school’s vision for its Leigh campus was one based on use of the town environs and interaction with the local people, and that the overarching concept of a community as a classroom entailed Hayden College becoming part of the Leigh community. The nature and quality of the relationship is explored by contrasting the school’s vision with the community’s view of Hayden’s membership of the Leigh community. Inquiry into the idea of a community as a classroom was approached by studying ‘community’ as an ideal concept. The thesis argues that the Hayden in Leigh development is a coincidence of educational and social ideals, clarifying what it means to be part of a community using conceptual analysis of qualitative data collected from the field. The theoretical stance and empirical material in this research show the way in which the power of the concept of community resides at the ideal level. The research finds that the nature of this school-community partnership is characterized by learning exchange and small town renewal but that a threat to the quality of the relationship between college and community is contained in disparate understandings of what constitutes community life. The implications of these findings for the post-Hayden Leigh community and rural schools and communities more generally are that the association of curriculum objectives with community development objectives depends on a healthy reciprocal relationship.
- Description: Doctor of Philosophy
- Authors: Downey, Tamara
- Date: 2002
- Type: Text , Thesis , PhD
- Full Text:
- Description: This thesis presents the Leigh community’s view of the impact of Hayden College on Leigh. The study establishes ‘community’ as the key aspect of this atypical school-community partnership in the context of research which shows that effective school-community partnerships are socially and economically beneficial for rural communities. The research question addresses the relationship between a particular college and a specific community. Hayden College was attracted to life in Leigh as a source of learning for its students and to community life in Leigh in particular. The research demonstrates that the school’s vision for its Leigh campus was one based on use of the town environs and interaction with the local people, and that the overarching concept of a community as a classroom entailed Hayden College becoming part of the Leigh community. The nature and quality of the relationship is explored by contrasting the school’s vision with the community’s view of Hayden’s membership of the Leigh community. Inquiry into the idea of a community as a classroom was approached by studying ‘community’ as an ideal concept. The thesis argues that the Hayden in Leigh development is a coincidence of educational and social ideals, clarifying what it means to be part of a community using conceptual analysis of qualitative data collected from the field. The theoretical stance and empirical material in this research show the way in which the power of the concept of community resides at the ideal level. The research finds that the nature of this school-community partnership is characterized by learning exchange and small town renewal but that a threat to the quality of the relationship between college and community is contained in disparate understandings of what constitutes community life. The implications of these findings for the post-Hayden Leigh community and rural schools and communities more generally are that the association of curriculum objectives with community development objectives depends on a healthy reciprocal relationship.
- Description: Doctor of Philosophy
Why winning a war is no longer necessary : modern warfare and the United States of America through the prism of the wars of Vietnam and Iraq
- Authors: Driver, Strobe
- Date: 2010
- Type: Text , Thesis , PhD
- Full Text:
- Description: This thesis explores the role of warfare and the United States of America (US) in contemporary times. Prior to this, however, pre-modern warfare is examined to illustrate its dynamics prior to the emergence of the nation-state... This thesis is original because it steps beyond the boundaries of what war research has focussed on, which directly postulates victory or defeat in war is what provides unambiguous power-stakes. The thesis addresses why it is no longer necessary to win a war in order for power to be unambiguous and I contend, not needing to win a war, in the traditional sense of the term is the new objective of the US military, and the way in which this is accomplished is examined in detail."
- Description: Doctor of Philosophy
- Authors: Driver, Strobe
- Date: 2010
- Type: Text , Thesis , PhD
- Full Text:
- Description: This thesis explores the role of warfare and the United States of America (US) in contemporary times. Prior to this, however, pre-modern warfare is examined to illustrate its dynamics prior to the emergence of the nation-state... This thesis is original because it steps beyond the boundaries of what war research has focussed on, which directly postulates victory or defeat in war is what provides unambiguous power-stakes. The thesis addresses why it is no longer necessary to win a war in order for power to be unambiguous and I contend, not needing to win a war, in the traditional sense of the term is the new objective of the US military, and the way in which this is accomplished is examined in detail."
- Description: Doctor of Philosophy
Examining factors that influence the relationship between personality and stress
- Authors: Duggan, Leanne
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Individual differences in the stress response have been linked with numerous factors, including personality traits and mindfulness. Selye (1950) was among the first to detail the physiological stress response that takes place during a stressful event, or after exposure to a stressor. These responses include heart rate changes and the secretion of cortisol into the blood stream, which are key physiological indicators that a stress response is taking place. Lazarus and Folkman (1984) examined appraisal of stressful events, determining that this is crucial to the stress experience. An extension of Lazarus and Folkman’s cognitive appraisal theory was offered by Vollrath (2001), suggesting an individual’s personality accentuates our stress response, therefore, offering an explanation for the individual differences evident in stress responses. The relationship between personality and stress is not straight forward, and other factors, such as affect and mindfulness, may influence this relationship. Thus, this dissertation is divided into three studies. Study 1 examined the moderating and mediating factors of affect on the relationship between personality traits and perceived stress. A total of 290 adults (71% female; Mage = 35.0 years, SD = 12.92) completed an online questionnaire package, comprising of the Perceived Stress Scale, Big Five Inventory, Positive and Negative Affect Schedule, and a number of demographic questions. A hierarchical regression showed that 56% of the variance in perceived stress was explained by personality and affect, and when all personality traits were viewed concurrently and with affect, neuroticism was the only one to significantly explain variance in perceived stress. No moderation effects were found in Study 1 however, positive affect partially mediated the relationship between neuroticism and perceived stress. Study 2 aimed to further the findings of Study 1 by investigating whether trait mindfulness impacted the relationship between personality and stress. A total of 266 adults (70% female; Mage = 34.0 years, SD = 12.68) completed an online questionnaire package, consisting of the Perceived Stress Scale, Big Five Inventory, and Carolina Empirically Derived Mindfulness Scale. A hierarchical regression showed that 58% of the variance in perceived stress was explained by personality and trait mindfulness. When all personality traits and trait mindfulness were viewed together, neuroticism and agreeableness were the only personality traits to significantly explain variance in perceived stress. The sub-scale trait mindfulness attention significantly moderated the relationship between agreeableness and perceived stress, while a partial mediation was found between neuroticism and the sub-scale trait mindfulness acceptance. Study 3 investigated the effectiveness of a brief state-based mindfulness intervention on physiological (cortisol and heart rate) and psychological stress responses, in a participant matched design. A total of 20 participants (60% female; Mage = 34.60 years, SD = 14.68) were recruited from Studies 1 and/or 2 and matched based on gender, dominant personality trait (found in Study 1 and 2), and perceived stress. One participant in each matched pair was then randomly allocated to the mindfulness experimental, or control, group. The mindfulness experimental group completed a 10-minute breathing exercise, prior to completing the Trier Social Stress Test, a verbal presentation and arithmetic task, designed to induce stress. The control group did not complete any activity prior to the stress test. Comparison of the groups indicated that no significant differences in perceived stress were evident pre-post- intervention. Changes in heart rate were noted for all participants during the intervention, though no difference was evident between groups. The results of Study 3 indicate a mindfulness breathing exercise makes little difference to physiological stress responses during a stress task. The combined findings of this dissertation indicate that personality traits can influence the likelihood of an individual experiencing stress. Mindfulness and affect also impact on the relationship between personality and stress and offer some insight into the individual experience of stress responses.
- Description: Doctor of Philosophy
- Authors: Duggan, Leanne
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Individual differences in the stress response have been linked with numerous factors, including personality traits and mindfulness. Selye (1950) was among the first to detail the physiological stress response that takes place during a stressful event, or after exposure to a stressor. These responses include heart rate changes and the secretion of cortisol into the blood stream, which are key physiological indicators that a stress response is taking place. Lazarus and Folkman (1984) examined appraisal of stressful events, determining that this is crucial to the stress experience. An extension of Lazarus and Folkman’s cognitive appraisal theory was offered by Vollrath (2001), suggesting an individual’s personality accentuates our stress response, therefore, offering an explanation for the individual differences evident in stress responses. The relationship between personality and stress is not straight forward, and other factors, such as affect and mindfulness, may influence this relationship. Thus, this dissertation is divided into three studies. Study 1 examined the moderating and mediating factors of affect on the relationship between personality traits and perceived stress. A total of 290 adults (71% female; Mage = 35.0 years, SD = 12.92) completed an online questionnaire package, comprising of the Perceived Stress Scale, Big Five Inventory, Positive and Negative Affect Schedule, and a number of demographic questions. A hierarchical regression showed that 56% of the variance in perceived stress was explained by personality and affect, and when all personality traits were viewed concurrently and with affect, neuroticism was the only one to significantly explain variance in perceived stress. No moderation effects were found in Study 1 however, positive affect partially mediated the relationship between neuroticism and perceived stress. Study 2 aimed to further the findings of Study 1 by investigating whether trait mindfulness impacted the relationship between personality and stress. A total of 266 adults (70% female; Mage = 34.0 years, SD = 12.68) completed an online questionnaire package, consisting of the Perceived Stress Scale, Big Five Inventory, and Carolina Empirically Derived Mindfulness Scale. A hierarchical regression showed that 58% of the variance in perceived stress was explained by personality and trait mindfulness. When all personality traits and trait mindfulness were viewed together, neuroticism and agreeableness were the only personality traits to significantly explain variance in perceived stress. The sub-scale trait mindfulness attention significantly moderated the relationship between agreeableness and perceived stress, while a partial mediation was found between neuroticism and the sub-scale trait mindfulness acceptance. Study 3 investigated the effectiveness of a brief state-based mindfulness intervention on physiological (cortisol and heart rate) and psychological stress responses, in a participant matched design. A total of 20 participants (60% female; Mage = 34.60 years, SD = 14.68) were recruited from Studies 1 and/or 2 and matched based on gender, dominant personality trait (found in Study 1 and 2), and perceived stress. One participant in each matched pair was then randomly allocated to the mindfulness experimental, or control, group. The mindfulness experimental group completed a 10-minute breathing exercise, prior to completing the Trier Social Stress Test, a verbal presentation and arithmetic task, designed to induce stress. The control group did not complete any activity prior to the stress test. Comparison of the groups indicated that no significant differences in perceived stress were evident pre-post- intervention. Changes in heart rate were noted for all participants during the intervention, though no difference was evident between groups. The results of Study 3 indicate a mindfulness breathing exercise makes little difference to physiological stress responses during a stress task. The combined findings of this dissertation indicate that personality traits can influence the likelihood of an individual experiencing stress. Mindfulness and affect also impact on the relationship between personality and stress and offer some insight into the individual experience of stress responses.
- Description: Doctor of Philosophy
Seeds, soils and moisture : ecophysiology to inform mine site restoration in arid zones
- Authors: Duncan, Corrine
- Date: 2019
- Type: Text , Thesis , PhD
- Full Text:
- Description: Mining in arid regions of Australia is followed by restoration and rehabilitation efforts. However, attempts to reintroduce many woody plant species have been unsuccessful. Water is the key limiting resource to plant growth and seed germination in arid zones. In this thesis, I investigated ecophysiological processes that may help improve recruitment across novel arid landscapes. I tested seed traits and dormancy cues of eight keystone plants and found that six of them had non-dormant, rapidly germinating seeds; a trait we propose is an adaptation to the region’s unpredictable rainfall. To identify the germination niche of species, I incubated seeds under different temperatures and water potentials, and found drought avoidance to be an important survival strategy for arid species. I collected soil samples to compare biophysicochemical properties of reconstructed soils to remnant ecosystems, and found that the distribution of clay content in the reconstructed soils did not mirror the remnant soils, compromising their ability to sustain perennial vegetation. I also monitored soil moisture and found that soil reconstruction reduces rainfall infiltration and retention, and subsequently increases evaporation. The synthesis of these results demonstrate some of the limitations to successful restoration in these systems, such as (1) unknown dormancy cues and poor seed longevity, (2) infrequent and episodic plant recruitment due to water limitation, and (3) reduced hydrological function of reconstructed soils. The failure to reinstate hydrological function is the major constraint to ecological restoration in this arid zone. Nonetheless, results from this study suggest that restoration is possible through more strategic use of seed, careful selection of drought tolerant species, and increasing soil moisture. Further failures to reinstate ecosystem function and community dynamics in arid zones with reconstructed soils can be prevented by understanding the edaphic constraints to plant establishment, and ameliorating conditions to mimic ecohydrological processes in remnant ecosystems.
- Description: Doctor of Philosophy
- Authors: Duncan, Corrine
- Date: 2019
- Type: Text , Thesis , PhD
- Full Text:
- Description: Mining in arid regions of Australia is followed by restoration and rehabilitation efforts. However, attempts to reintroduce many woody plant species have been unsuccessful. Water is the key limiting resource to plant growth and seed germination in arid zones. In this thesis, I investigated ecophysiological processes that may help improve recruitment across novel arid landscapes. I tested seed traits and dormancy cues of eight keystone plants and found that six of them had non-dormant, rapidly germinating seeds; a trait we propose is an adaptation to the region’s unpredictable rainfall. To identify the germination niche of species, I incubated seeds under different temperatures and water potentials, and found drought avoidance to be an important survival strategy for arid species. I collected soil samples to compare biophysicochemical properties of reconstructed soils to remnant ecosystems, and found that the distribution of clay content in the reconstructed soils did not mirror the remnant soils, compromising their ability to sustain perennial vegetation. I also monitored soil moisture and found that soil reconstruction reduces rainfall infiltration and retention, and subsequently increases evaporation. The synthesis of these results demonstrate some of the limitations to successful restoration in these systems, such as (1) unknown dormancy cues and poor seed longevity, (2) infrequent and episodic plant recruitment due to water limitation, and (3) reduced hydrological function of reconstructed soils. The failure to reinstate hydrological function is the major constraint to ecological restoration in this arid zone. Nonetheless, results from this study suggest that restoration is possible through more strategic use of seed, careful selection of drought tolerant species, and increasing soil moisture. Further failures to reinstate ecosystem function and community dynamics in arid zones with reconstructed soils can be prevented by understanding the edaphic constraints to plant establishment, and ameliorating conditions to mimic ecohydrological processes in remnant ecosystems.
- Description: Doctor of Philosophy
Random finite element method prediction and optimisation for open pit mine slope stability analysis
- Authors: Dyson, Ashley
- Date: 2020
- Type: Text , Thesis , PhD
- Full Text:
- Description: Inherent soil variability can have significant effects on the stability of open-pit mine slopes. In practice, the spatial variability of materials is not commonly considered as a routine component of slope stability analysis. The process of quantifying spatially variable parameters, as well as the modelling of their behaviour is often a complex undertaking. Currently, there are no large-scale commercial software packages containing in-built methods for modelling spatial variability within the Finite Element environment. Furthermore, conventional Limit Equilibrium Methods (LEM) incorporating spatial variability are unable to consider the stress/strain characteristics of these materials. The following research seeks to accurately model the slope mechanics of spatially variable soils, adopting The Random Finite Element Method (RFEM) developed by Griffiths and Fenton (2004) to determine slope failure mechanisms and safety factors. Techniques are developed to produce a set of optimised Random Finite Element Method simulations using the Monte Carlo Method. Additionally, random field analysis techniques are investigated to compare and categorise soil parameter fluctuation, providing a direct relationship between random field properties and slope failure surfaces. Optimisation and analysis techniques are implemented to examine the effects of cross-sectional geometries and input parameter distributions on failure mechanisms, safety factors and probabilities of failure. Cross-sectional RFEM analysis is performed in the Finite Element Method (FEM) software package Abaqus, with the techniques of this research demonstrated for a large open-pit brown coal mine located in the state of Victoria, Australia. The outcome of this research is a comprehensive procedure for optimised RFEM simulation and analysis.
- Description: Doctor of Philosophy
- Authors: Dyson, Ashley
- Date: 2020
- Type: Text , Thesis , PhD
- Full Text:
- Description: Inherent soil variability can have significant effects on the stability of open-pit mine slopes. In practice, the spatial variability of materials is not commonly considered as a routine component of slope stability analysis. The process of quantifying spatially variable parameters, as well as the modelling of their behaviour is often a complex undertaking. Currently, there are no large-scale commercial software packages containing in-built methods for modelling spatial variability within the Finite Element environment. Furthermore, conventional Limit Equilibrium Methods (LEM) incorporating spatial variability are unable to consider the stress/strain characteristics of these materials. The following research seeks to accurately model the slope mechanics of spatially variable soils, adopting The Random Finite Element Method (RFEM) developed by Griffiths and Fenton (2004) to determine slope failure mechanisms and safety factors. Techniques are developed to produce a set of optimised Random Finite Element Method simulations using the Monte Carlo Method. Additionally, random field analysis techniques are investigated to compare and categorise soil parameter fluctuation, providing a direct relationship between random field properties and slope failure surfaces. Optimisation and analysis techniques are implemented to examine the effects of cross-sectional geometries and input parameter distributions on failure mechanisms, safety factors and probabilities of failure. Cross-sectional RFEM analysis is performed in the Finite Element Method (FEM) software package Abaqus, with the techniques of this research demonstrated for a large open-pit brown coal mine located in the state of Victoria, Australia. The outcome of this research is a comprehensive procedure for optimised RFEM simulation and analysis.
- Description: Doctor of Philosophy
Mathematical models of dynamic reconfiguration of telecommunication networks
- Authors: Dzalilov, Zari
- Date: 2004
- Type: Text , Thesis , PhD
- Full Text:
- Description: In this thesis we examine mathematical models for dynamical reconfiguration of telecommunication networks. Dynamical configuration is one of the most important problems in the field of network management. In the case of some part of the network being damaged the system should maintain its operations, taking into account the new conditions. This can be achieved by using the residual capacity of the system if it is available. If there were not enough residual capacity, the managers of the system need to involve some of the unaffected traffic in order to reorganize traffic. A prolonged breakdown will push some customers to change their provider; there is also a lost [sic] of profit because of breakdowns, that can be considered as a certain implicit penalty. To reorganize traffic by using new routes we should have a flexible routing system.
- Description: Doctor of Philosophy
- Authors: Dzalilov, Zari
- Date: 2004
- Type: Text , Thesis , PhD
- Full Text:
- Description: In this thesis we examine mathematical models for dynamical reconfiguration of telecommunication networks. Dynamical configuration is one of the most important problems in the field of network management. In the case of some part of the network being damaged the system should maintain its operations, taking into account the new conditions. This can be achieved by using the residual capacity of the system if it is available. If there were not enough residual capacity, the managers of the system need to involve some of the unaffected traffic in order to reorganize traffic. A prolonged breakdown will push some customers to change their provider; there is also a lost [sic] of profit because of breakdowns, that can be considered as a certain implicit penalty. To reorganize traffic by using new routes we should have a flexible routing system.
- Description: Doctor of Philosophy
Harvesting stormwater : Testing the paradigm by assessing the impacts with an inter-disciplinary case study
- Authors: Ebbs, David
- Date: 2019
- Type: Text , Thesis , PhD
- Full Text:
- Description: Integrated Urban Water Management (IUWM) is often proposed as a framework for comprehensively managing the water cycle in urban areas. One of the tenets of IUWM is that, due to increased impervious area, stormwater runoff in excess of the natural flow could be captured and used to supplement the water supply, while mitigating the environmental impact. This thesis tests that theory through an inter-disciplinary case study utilising legacy data for the regional city of Ballarat, Australia. The case study approach has enabled the water balance of an urbanised catchment to be better understood in various ways and provided for five tightly nested research projects, being: 1. Does the long-term development of water management within a city provide insight into what drives decisions, therefore informing future progress? 2. Can the drivers of water use be adequately determined from a community wide, historical analysis such that future regulatory decisions can be informed? 3. Will assessment of the long-term streamflow of a river, combined with an urban water balance of the catchment, enable the identification of additional stormwater flow due to urbanisation, in excess of the natural flow? 4. Can the impact of urbanisation on groundwater be identified (i.e. trends quantified or qualified) from the city’s legacy data or any available data sources, or models? 5. Is it possible to establish a comparative analysis technique that accounts for the uncertainty of information which changes over time, maintains intellectual rigour and is understandable and easily presented? IUWM was found, perhaps unsurprisingly, to be a complex problem with the challenges being very contextual on the particular catchment and city being studied. This research revealed that evidence of greater volumes of water being generated from increasingly urbanised impervious catchments is not easy to find. This finding may challenge conventional thinking and means that decisions on stormwater harvesting and WSUD practices more broadly should first be informed by evidence of the water balance. This research also revealed some very significant challenges in the water industry with finding and effectively using very dispersed data sets which are held and managed across multiple water agencies in various digital and hard copy formats. Information and data availability is critical to all aspects of IUWM, including in the measurement of its success, and so this research reminds the water industry of the importance of its data management practices.
- Description: Doctor of Philosophy
- Authors: Ebbs, David
- Date: 2019
- Type: Text , Thesis , PhD
- Full Text:
- Description: Integrated Urban Water Management (IUWM) is often proposed as a framework for comprehensively managing the water cycle in urban areas. One of the tenets of IUWM is that, due to increased impervious area, stormwater runoff in excess of the natural flow could be captured and used to supplement the water supply, while mitigating the environmental impact. This thesis tests that theory through an inter-disciplinary case study utilising legacy data for the regional city of Ballarat, Australia. The case study approach has enabled the water balance of an urbanised catchment to be better understood in various ways and provided for five tightly nested research projects, being: 1. Does the long-term development of water management within a city provide insight into what drives decisions, therefore informing future progress? 2. Can the drivers of water use be adequately determined from a community wide, historical analysis such that future regulatory decisions can be informed? 3. Will assessment of the long-term streamflow of a river, combined with an urban water balance of the catchment, enable the identification of additional stormwater flow due to urbanisation, in excess of the natural flow? 4. Can the impact of urbanisation on groundwater be identified (i.e. trends quantified or qualified) from the city’s legacy data or any available data sources, or models? 5. Is it possible to establish a comparative analysis technique that accounts for the uncertainty of information which changes over time, maintains intellectual rigour and is understandable and easily presented? IUWM was found, perhaps unsurprisingly, to be a complex problem with the challenges being very contextual on the particular catchment and city being studied. This research revealed that evidence of greater volumes of water being generated from increasingly urbanised impervious catchments is not easy to find. This finding may challenge conventional thinking and means that decisions on stormwater harvesting and WSUD practices more broadly should first be informed by evidence of the water balance. This research also revealed some very significant challenges in the water industry with finding and effectively using very dispersed data sets which are held and managed across multiple water agencies in various digital and hard copy formats. Information and data availability is critical to all aspects of IUWM, including in the measurement of its success, and so this research reminds the water industry of the importance of its data management practices.
- Description: Doctor of Philosophy
'You Beauty' Alex Jesaulenko An historical exploration of the migrant who became a legend
- Authors: Eddy, Daniel
- Date: 2019
- Type: Text , Thesis , PhD
- Full Text: false
- Description: The Austrian-born Alex Jesaulenko played football in the Victorian Football League (VFL) from 1967 to 1981. His rise to national prominence emerged during a period of great change within both Australian society and Australian rules football. This thesis, through a critical biographical approach, examines for the first time Jesaulenko’s early life, looking at his migrant experience and the role that Australian rules football played in aiding his integration into Australian society. It is not a kick-and-handball analysis of Jesaulenko’s entire football career; that has been extensively covered within copious amounts of primary and secondary sources. Instead, it explores his migrant journey – an important aspect of Jesaulenko’s life which has been largely overlooked – and the key developmental years of sporting education prior to emerging as a VFL champion. It concludes with one of, if not the most, iconic moments in the game’s history: Jesaulenko’s mark in the 1970 VFL grand final, which cemented his name within the Australian sporting consciousness. Australian rules football, and sport more generally, holds a unique place within society. Footballers, it can be argued, are archetypes for our daily dreams and aspirations; exalted figures that we afford status which few will experience in their everyday lives. Therefore, it is through the prism of Jesaulenko’s journey that we can learn more about the role Australian rules football has played for migrants integrating into Australian society.
- Description: Doctor of Philosophy
Multiculturalism : (re) intellectualising teaching
- Authors: Edmonds, George
- Date: 2007
- Type: Text , Thesis , PhD
- Full Text:
- Description: Doctor of Philosphy
- Authors: Edmonds, George
- Date: 2007
- Type: Text , Thesis , PhD
- Full Text:
- Description: Doctor of Philosphy
Implementing inclusion : classroom journeys
- Authors: Elvey, Moya
- Date: 2020
- Type: Text , Thesis , PhD
- Full Text:
- Description: This study interrogates the professional experiences, attitudes and pedagogical choices of eight classroom teachers in regular schools and inquires into their impact on the development of inclusive teaching practices. Approached from the perspective of an experienced teaching practitioner, the study responds to the call for an increased focus on the role of classroom teachers in implementing inclusion in schools. The study is underpinned by a theoretical stance that promotes the value of inclusive education through a human rights, access and equity framework. It advocates for the importance of overcoming the discriminatory practices that marginalise some students. Consistent with a qualitative, ethnographic methodology, observations and interviews with practicing teachers provide insights into the factors that encourage, and sometimes discourage, the enactment of inclusive pedagogies. The literature on inclusive education provides guidance throughout the data collection and analysis process. This includes frameworks designed by other researchers that outline and define inclusive teaching strategies. The study exposes the pivotal role that ongoing teacher professional learning, along with strategic guidance and support from colleagues and school leaders, plays in enhancing teacher capacity and positive attitudes towards student diversity. It also uncovers evidence that when medical reports and pressure from ‘others’ such as health professionals, encourage teachers to focus on student ‘deficits’ and ‘problems’, they are more likely to seek out and adopt strategies that marginalise and set some students apart from their peers. A fundamental finding of this study is that when teachers and their school leaders focus on developing understanding about ‘effective’ pedagogies - on quality education for all - responsive, inclusive, student-centred teaching approaches often become embedded in their everyday classroom practice.
- Description: PhD
- Authors: Elvey, Moya
- Date: 2020
- Type: Text , Thesis , PhD
- Full Text:
- Description: This study interrogates the professional experiences, attitudes and pedagogical choices of eight classroom teachers in regular schools and inquires into their impact on the development of inclusive teaching practices. Approached from the perspective of an experienced teaching practitioner, the study responds to the call for an increased focus on the role of classroom teachers in implementing inclusion in schools. The study is underpinned by a theoretical stance that promotes the value of inclusive education through a human rights, access and equity framework. It advocates for the importance of overcoming the discriminatory practices that marginalise some students. Consistent with a qualitative, ethnographic methodology, observations and interviews with practicing teachers provide insights into the factors that encourage, and sometimes discourage, the enactment of inclusive pedagogies. The literature on inclusive education provides guidance throughout the data collection and analysis process. This includes frameworks designed by other researchers that outline and define inclusive teaching strategies. The study exposes the pivotal role that ongoing teacher professional learning, along with strategic guidance and support from colleagues and school leaders, plays in enhancing teacher capacity and positive attitudes towards student diversity. It also uncovers evidence that when medical reports and pressure from ‘others’ such as health professionals, encourage teachers to focus on student ‘deficits’ and ‘problems’, they are more likely to seek out and adopt strategies that marginalise and set some students apart from their peers. A fundamental finding of this study is that when teachers and their school leaders focus on developing understanding about ‘effective’ pedagogies - on quality education for all - responsive, inclusive, student-centred teaching approaches often become embedded in their everyday classroom practice.
- Description: PhD
Co-encapsulation of Omega-3 fatty acids and probiotic bacteria through complex coacervation
- Authors: Eratte, Divya
- Date: 2016
- Type: Text , Thesis , PhD
- Full Text:
- Description: The research described in this thesis investigated the microencapsulation of omega-3 oil and probiotic bacteria together in a protein-polysaccharide complex coacervate matrix. The synergistic or competitive interactions between the probiotic bacteria and omega-3 fatty acids when packaged in a single microcapsule was determined including how best to utilise such interaction to achieve improved oxidative stability of omega-3 fatty acid and better survival of the probiotic bacteria. Encapsulation and co-encapsulation of tuna oil (O) and Lactobacillus casei 431 (P) as models of omega-3 and probiotic bacteria, respectively, were carried out and the works is described in this thesis in five distinct sections. (1) The optimisation of the complex coacervation process between whey protein isolate (WPI) and gum Arabic (GA). (2) Microencapsulation of tuna oil (O) in WPI-GA complex coacervates followed by spray and freeze drying to produce microcapsules (WPI-O-GA). (3) Microencapsulation of probiotic bacteria L. casei 431 (P) in WPI-GA complex coacervates followed by spray and freeze drying to produce microcapsules (WPI-P-GA). (4) Co-encapsulation of omega-3 oil and L. casei 431 together in WPI-GA coacervate matrix followed by spray and freeze drying to produce co-microcapsules (WPI-P-O-GA). (5) In-vitro digestion evaluation of co-microcapsules and microcapsules to indicate bioavailability. The viability of L. casei was significantly higher in WPI-P-O-GA co-microcapsules than in WPI-P-GA microcapsules in both spray and freeze dried microcapsules. The oxidative stability of tuna oil was significantly higher in spray dried co-capsules. Also, co-microencapsulation increased the survivability of L. casei during simulated digestion. There was no significant influence observed on the release properties of omega-3 oil due to co-microencapsulation. However, the total omega-3 fatty acids in the released oil during in-vitro digestion were found to be higher, when co-microencapsulated. Hence, co-microencapsulation was shown to protect the L. casei and deliver both viable cells and omega-3 oil to human intestine without any significant adverse effect on their functionality and properties.
- Description: Doctor of Philosophy
- Authors: Eratte, Divya
- Date: 2016
- Type: Text , Thesis , PhD
- Full Text:
- Description: The research described in this thesis investigated the microencapsulation of omega-3 oil and probiotic bacteria together in a protein-polysaccharide complex coacervate matrix. The synergistic or competitive interactions between the probiotic bacteria and omega-3 fatty acids when packaged in a single microcapsule was determined including how best to utilise such interaction to achieve improved oxidative stability of omega-3 fatty acid and better survival of the probiotic bacteria. Encapsulation and co-encapsulation of tuna oil (O) and Lactobacillus casei 431 (P) as models of omega-3 and probiotic bacteria, respectively, were carried out and the works is described in this thesis in five distinct sections. (1) The optimisation of the complex coacervation process between whey protein isolate (WPI) and gum Arabic (GA). (2) Microencapsulation of tuna oil (O) in WPI-GA complex coacervates followed by spray and freeze drying to produce microcapsules (WPI-O-GA). (3) Microencapsulation of probiotic bacteria L. casei 431 (P) in WPI-GA complex coacervates followed by spray and freeze drying to produce microcapsules (WPI-P-GA). (4) Co-encapsulation of omega-3 oil and L. casei 431 together in WPI-GA coacervate matrix followed by spray and freeze drying to produce co-microcapsules (WPI-P-O-GA). (5) In-vitro digestion evaluation of co-microcapsules and microcapsules to indicate bioavailability. The viability of L. casei was significantly higher in WPI-P-O-GA co-microcapsules than in WPI-P-GA microcapsules in both spray and freeze dried microcapsules. The oxidative stability of tuna oil was significantly higher in spray dried co-capsules. Also, co-microencapsulation increased the survivability of L. casei during simulated digestion. There was no significant influence observed on the release properties of omega-3 oil due to co-microencapsulation. However, the total omega-3 fatty acids in the released oil during in-vitro digestion were found to be higher, when co-microencapsulated. Hence, co-microencapsulation was shown to protect the L. casei and deliver both viable cells and omega-3 oil to human intestine without any significant adverse effect on their functionality and properties.
- Description: Doctor of Philosophy
Exploring the development of thinking in senior secondary mathematics : a focus on probability
- Authors: Ernst, Heather
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Higher order thinking skills have been identified as desirable although elusive outcomes of many educational curricula. Through a qualitative case study, the alignment between the three levels of the curriculum: intended, implemented, and attained, was examined to determine the tensions and possibilities in the development of mathematical and thinking skills in senior secondary students in Gippsland, a large regional area of Victoria, Australia. Probability was the mathematical content area of focus. Data from document analysis of the intended curriculum, textbooks as the implemented curriculum, and assessments as the attained curriculum, was combined with qualitative data from semi-structured interviews with twenty students and fourteen senior secondary mathematics teachers. These diverse data sources scaffolded each other to identify tensions and possibilities influencing development of student thinking in senior secondary mathematics. This research demonstrated that the flow of content via the intended-implemented-attained curriculum was not adequate to describe all the influences on student learning. The lens of Activity Theory (Engeström, 2001) came closer to capturing the related complexities whereby the textbooks, calculators, bound reference books and assessments, combined with the balance of agency demonstrated by the teachers and students, were found to both support and cause tensions within the activity system. Probability was found to be a valuable topic to study in relation to the development of thinking skills due to its relevance in decision making, how it linked many areas of mathematics and the uniqueness of the classic, experimental, and subjective views of probability. This study is significant in the contribution it makes to understanding the tensions and possibilities associated with the development of mathematical thinking relating to probability through the lens of Activity Theory. While the intended curriculum encouraged a range of thinking skills, this intended curriculum could be implemented in a way that promotes memorisation rather than the intended higher order thinking. This study concludes with recommendations for the curriculum designers, textbook publishers, teachers, and students which may support the development of mathematical and thinking skills.
- Description: Doctor of Philosophy
- Authors: Ernst, Heather
- Date: 2021
- Type: Text , Thesis , PhD
- Full Text:
- Description: Higher order thinking skills have been identified as desirable although elusive outcomes of many educational curricula. Through a qualitative case study, the alignment between the three levels of the curriculum: intended, implemented, and attained, was examined to determine the tensions and possibilities in the development of mathematical and thinking skills in senior secondary students in Gippsland, a large regional area of Victoria, Australia. Probability was the mathematical content area of focus. Data from document analysis of the intended curriculum, textbooks as the implemented curriculum, and assessments as the attained curriculum, was combined with qualitative data from semi-structured interviews with twenty students and fourteen senior secondary mathematics teachers. These diverse data sources scaffolded each other to identify tensions and possibilities influencing development of student thinking in senior secondary mathematics. This research demonstrated that the flow of content via the intended-implemented-attained curriculum was not adequate to describe all the influences on student learning. The lens of Activity Theory (Engeström, 2001) came closer to capturing the related complexities whereby the textbooks, calculators, bound reference books and assessments, combined with the balance of agency demonstrated by the teachers and students, were found to both support and cause tensions within the activity system. Probability was found to be a valuable topic to study in relation to the development of thinking skills due to its relevance in decision making, how it linked many areas of mathematics and the uniqueness of the classic, experimental, and subjective views of probability. This study is significant in the contribution it makes to understanding the tensions and possibilities associated with the development of mathematical thinking relating to probability through the lens of Activity Theory. While the intended curriculum encouraged a range of thinking skills, this intended curriculum could be implemented in a way that promotes memorisation rather than the intended higher order thinking. This study concludes with recommendations for the curriculum designers, textbook publishers, teachers, and students which may support the development of mathematical and thinking skills.
- Description: Doctor of Philosophy
Raw politics : politics without the State
- Authors: Eyssens, Terry
- Date: 2011
- Type: Text , Thesis , PhD
- Full Text:
- Description: "... the thesis examines traditional anarchist theorisations of 'politics without the state' and finds them to be as contained by the State and its founding concepts as the political liberalism of our present. All that remains to be salvaged from anarchist thought is the idea expressed in its name: that is, to be 'without rulers'. In order to escape such conceptual containment, Raw politics aims to produce a 'stripped-down' conceptualisation of politics." - Abstract.
- Description: Doctor of Philosophy
- Authors: Eyssens, Terry
- Date: 2011
- Type: Text , Thesis , PhD
- Full Text:
- Description: "... the thesis examines traditional anarchist theorisations of 'politics without the state' and finds them to be as contained by the State and its founding concepts as the political liberalism of our present. All that remains to be salvaged from anarchist thought is the idea expressed in its name: that is, to be 'without rulers'. In order to escape such conceptual containment, Raw politics aims to produce a 'stripped-down' conceptualisation of politics." - Abstract.
- Description: Doctor of Philosophy
Reliability-based design optimisation methods in large scale systems
- Authors: Ezzati, Ghasem
- Date: 2015
- Type: Text , Thesis , PhD
- Full Text:
- Description: Doctor of Philosophy
- Description: Structural optimisation is an important field of applied mathematics, which has proved useful in engineering projects. Reliability-based design optimisation (RBDO) can be considered a branch of structural optimisation. Different RBDO approaches have been applied in real world problems (e.g. vehicle side impact model, short column design, etc.). Double-loop, single-loop, and decoupled approaches are three categories in RBDO. This research focuses on double-loop approaches, which consider reliability analysis problems in their inner loops and design optimisation calculations in their outer loops. In recent decades, double-loop approaches have been studied and modified in order to improve their stability and efficiency, but many shortcomings still remain, particularly regarding reliability analysis methods. This thesis will concentrate on development of new reliability analysis methods that can be applied to solve RBDO problems. As a local optimisation algorithm, the conjugate gradient method will be adopted. Furthermore, a new method will be introduced to solve a reliability analysis problem in the polar space. The reliability analysis problem must be transformed into an unconstrained optimisation problem before solving in the polar space. Two methods will be introduced here and their stability and efficiency will be compared with the existing methods via numerical experiments. Next, we consider applications of RBDO models to electricity networks. Most of the current optimisation models of these networks are categorised as deterministic design optimisation models. A probabilistic constraint is introduced in this thesis for electricity networks. For this purpose, a performance function must be defined for a network in order to define safety and failure conditions. Then, new non-deterministic design optimisation models will be formulated for electricity networks by using the mentioned probabilistic constraint. These models are designed to keep failure probability of the network below a predetermined and accepted safety level.
- Authors: Ezzati, Ghasem
- Date: 2015
- Type: Text , Thesis , PhD
- Full Text:
- Description: Doctor of Philosophy
- Description: Structural optimisation is an important field of applied mathematics, which has proved useful in engineering projects. Reliability-based design optimisation (RBDO) can be considered a branch of structural optimisation. Different RBDO approaches have been applied in real world problems (e.g. vehicle side impact model, short column design, etc.). Double-loop, single-loop, and decoupled approaches are three categories in RBDO. This research focuses on double-loop approaches, which consider reliability analysis problems in their inner loops and design optimisation calculations in their outer loops. In recent decades, double-loop approaches have been studied and modified in order to improve their stability and efficiency, but many shortcomings still remain, particularly regarding reliability analysis methods. This thesis will concentrate on development of new reliability analysis methods that can be applied to solve RBDO problems. As a local optimisation algorithm, the conjugate gradient method will be adopted. Furthermore, a new method will be introduced to solve a reliability analysis problem in the polar space. The reliability analysis problem must be transformed into an unconstrained optimisation problem before solving in the polar space. Two methods will be introduced here and their stability and efficiency will be compared with the existing methods via numerical experiments. Next, we consider applications of RBDO models to electricity networks. Most of the current optimisation models of these networks are categorised as deterministic design optimisation models. A probabilistic constraint is introduced in this thesis for electricity networks. For this purpose, a performance function must be defined for a network in order to define safety and failure conditions. Then, new non-deterministic design optimisation models will be formulated for electricity networks by using the mentioned probabilistic constraint. These models are designed to keep failure probability of the network below a predetermined and accepted safety level.