Description:
Excavating the ground for different purposes, such as extracting valuable materials or undertaking urban construction, may cause concerns regarding the stability of the formed slopes, which can affect the environment, the economy, and human lives. Slope stability analysis in large-scale and deep excavations such as open-pit mines is challenging due to uncertainties regarding varying material parameters, complex field conditions and lack of or insufficient data such as pore water pressure distribution, in-situ stress conditions, and discontinuities. Despite different advanced analytical and numerical slope stability techniques having been developed, slope stability analysis may produce unreliable conclusions due to these uncertainties and challenges. This study’s objective is to investigate the effect of different factors associated with slope stability through a case study of the Yallourn brown coal open pit mine in Australia. In this study, the two most common slope stability methods—the Limit Equilibrium Method (LEM) and the Finite Element Method (FEM)—were employed. A comprehensive study was conducted to determine how the generation and dissipation of Negative Excess Pore-Water Pressure (NEPWP) affect slope stability assessments. Additionally, due to the complex geological stratigraphy of the site, different scenarios for geological layering were defined and investigated for the slope stability analyses. Moreover, the sensitivity of the slope stability assessment to not only different material characteristics but also different formulations and assumptions of LEM and FEM are presented.
Description:
Batter instability is one of the major geotechnical concerns in open-cut mining of recent decades. A key factor in undertaking any stability assessment of batters and determining their Factor of Safety (FoS) against instability is understanding the geotechnical properties of the material comprising the batters. These geotechnical properties usually include stiffness and strength under various loading conditions such as compression, extension and creep. This thesis presents a comprehensive study of the geotechnical properties of materials comprising the batters in the Yallourn open-cut mine in Victoria, Australia, located at one of the largest sources of brown coal in the world. The materials studied in this research are Victorian Brown Coal (VBC) and fine-grained interseam material (containing mainly silt and clay particles). The presented study is based on four key steps undertaken during the research project: 1. Field investigation This step included drilling boreholes at the mine floor and mine crest and recovering samples of VBC and interseam for laboratory testing. Sample trays were logged to provide lithology data required for model generation for numerical modelling undertaken by other PhD students. 2. Laboratory testing This step involved a wide range of laboratory tests on undisturbed samples of VBC and interseam material to investigate soil characteristics, stiffness and strength of tested materials. 3. Data analysis and parameter determination This step included analysing the laboratory test results, preparing stress-strain plots and determining material properties such as pre-consolidation pressure, stiffness and strength. 4. Numerical analysis and model calibration This step included selecting proper constitutive models and determining the models’ parameters based on laboratory tests. The capability of models was then examined by verifying numerical model simulation against laboratory test results. The laboratory tests indicated that VBC shows a hardening feature in compression, leading to brittle failure, while also showing a sharp post-peak softening behaviour. The tests also showed that the interseam material is heavily over-consolidated with a dilative hardening feature. The stiffness and shear strength of the interseam were found to be sensitive to the applied strain rate. The conducted creep tests (applying constant shear stress for a selected period) under triaxial undrained conditions resulted in developing pore water pressure leading to creep failure. Based on the laboratory test results and the obtained geotechnical features of the tested materials, Hardening Soil (HS) and Soft Soil Creep (SSC) models were chosen to describe the geotechnical behaviour of both VBC and interseam material. Both models were calibrated using test results and employed in simulated laboratory tests, including oedometer and triaxial Consolidated Undrained (CU) tests using the Finite Element Method (FEM). This study indicates that, although most of the models’ parameters were determined successfully based on laboratory test results, engineering judgement and back calculating were required to find the best fit for the numerical simulations. The numerical modelling of oedometer and triaxial tests showed that the nonlinear hardening behaviour of VBC and interseam material was captured by the HS model. The stress path in triaxial CU tests and the stress-strain curve in unloading-reloading were simulated well by the HS model. The strain-rate dependency and creep behaviour of interseam material were simulated well by the SSC model, indicating that this model can predict the long-term behaviour of interseam material.
Description:
This thesis addresses the gap that has existed in Ballarat’s historiography regarding the historical neglect and ignorance of Chinese family narratives and their life experiences. In doing so this thesis presents a longitudinal, three generational study of an immigrant Ballarat Chinese family from the early 1860s until the 1950s. It examines how members of each Tong Way generation strove to gain acceptance and establish an enduring sense of cultural belonging in a former regional, Victorian gold mining city. An ancestor, Liu Chou Hock, was a sojourner who arrived on the Haddon goldfield in 1862 and successfully worked a claim. Within three years, he returned to his village, Wang Tung, in Taishan, China. His experience was in sharp contrast to that of his son John Tong Way (Liu’ Zongwei) who permanently settled in Ballarat. The family strived to integrate against a background of migrant adjustment, ethnic discrimination and later a policy of assimilation. These factors represented a challenge for all Chinese who remained until the White Australia Policy was abandoned by the Whitlam Labor government in 1973. Unlike Caucasian immigrants, who could assimilate, whilst retaining certain features of their ethnic identification, the Chinese were culturally alienated and often excluded from everyday cultural life and practice. They represented a demographically significant ethnic minority. The thesis also compares the experiences of the Ballarat and Bendigo Chinese communities in order to examine the similarities and differences. In doing so, it analyses how they were able to establish a sense of belonging in their respective communities. The analysis of the Ballarat family’s experiences, combined with that of other Chinese descent families forms the basis of an extended case study. One that argues that adaptation was necessitated by their individual aspirations for acceptance, respectability and success.
Description:
Human wildlife conflict (HWC) is a highly studied but unresolved aspect of wildlife management. To further knowledge on HWC, this study used a multidisciplinary approach to investigate HWC implications for local people living adjacent to two key tiger conservation reserves in Nepal. The study also assessed the potential to redistribute financial benefits accruing from predator conservation to those bearing costs through associated HWC. Secondary data and anecdotal reports suggest that local people experience significant direct and indirect costs from predator conservation through livestock losses following attacks by common leopards and Bengal tigers, and additionally, crop losses due to their prey species plus two mega herbivores (elephant and one-horned rhinoceros). To investigate this situation, data regarding HWC incidents and costs were sourced through interviews with 422 local households, direct observations, and stakeholder interviews. Collected data included livestock loss (5-year time-period) and crop loss (1-year time-period). Complementary direct observation data collated livestock loss and crop damage for 12 months. Interviews were conducted also with park visitors (N=387) and tourism business owners (N=74). Results showed that tigers are involved in significantly fewer depredation events compared to leopards. Leopards predominantly killed small to medium livestock whereas tigers selected both small to medium and large sized livestock. Livestock depredation events occurred more frequently in livestock corrals relative to forest zones or crop fields. Rates of livestock losses per household per year self-reported during interviews with local people were found higher when compared to those observed by direct measurement. Prey species of tigers and leopards (most often wild boar and chital) were involved in more frequently in crop raiding events, and caused more crop damage, when compared that caused by mega herbivores. Quantities of crops lost per household were lowest in communities where effective physical barriers to wildlife were present. Park visitors and tourism business owners indicated willingness to pay for conservation of tigers and for compensation of farmers for the losses caused by tigers and their prey species. Study findings support several key recommendations proposed to mitigate negative HWC effects in the study area. These include financial support for local communities to build predator proof livestock corrals and establishment of effective physical barriers at the park borders. A dedicated tariff for park visitors and a levy for tourism business owners are also recommended to fund ongoing predator conservation and support financial compensation for local farmers affected by HWC.
Description:
Theatre is a powerful way to investigate the operation of borders due to its live, immediate focus on representation and its potential to test a society’s boundaries. This practice-led research incorporates a performance and an exegesis to ask, ‘How can site-specific theatre that investigates the performance of borders and heterotopia enhance understanding of individual responsibility in postcolonising Australia?’ I take the term postcolonising from Aileen Moreton-Robinson, who argues that the beneficiaries of settler-colonialism (such as myself) must accept responsibility for the past before attempting to address its injustices. As an artist, I am inspired by anthropologist, Deborah Bird Rose, who privileges storytelling as a way of breaking boundaries between the past and present. Michel Foucault coined the term heterotopia (other place) to denote a single real space that juxtaposes several sites that are incompatible. This evokes the contemporary Australian situation of contested sovereignty. As Joanne Tompkins argues, heterotopic theatre can enact such a space in order to raise awareness and work towards societal change. My research demonstrates this both theoretically and practically. My exegesis crosses borders to create a heterotopia by juxtaposing past, present and possible futures, stories and theoretical understandings from diverse sources. The performance created at my home, rather than in a theatre, layers family, local, Australian and international histories to highlight the continuum between the personal and political, and to question current structures of power and knowledge. I use site-specific theatre to diminish the boundaries between performer and audience, creating a visceral heterotopia that facilitates a deeper understanding of personal responsibility in the context of postcolonising Australia.
Description:
One of the most significant challenges of open-cut mining is to provide stability for the excavated slopes. Unrealistic predictions of the slopes’ behaviour during and after mining operations can lead to the failure of slopes, and this may pose a threat to human lives, the economy, and the environment. By excavating soft rock masses in open-cut mines, pre-existing joints can open and new joints can form behind excavated slopes. This phenomenon is due to the geotechnical character of the materials and stress relief movements of the excavated slopes. The stability of slopes in the rock masses is significantly influenced by the existence of discontinuities such as joints. The water flows in the opened joints can change the pore water pressure distribution in the slopes. The interaction between the joints and the water may impose different loading scenarios on the open-cut mines and put the safety of mining operations at risk. The analysis of slope stability can become more complicated because of the presence of water, discontinuities, and their interaction within the slopes in open-cut mines. This study investigates the hydromechanical interactions in the saturated jointed slopes due to pore water pressure changes. The second-largest open-cut mine in Australia, the Yallourn brown coal open-cut mine located in Victoria, was chosen as the case study for this research. In this study, several coupled pore fluid diffusion and stress-strain analyses are conducted using the extended finite element method (XFEM) in conjunction with the finite element method (FEM). This study firstly examines a joint aperture and pore water pressure changes of the excavated jointed slope due to installing a drainage system and backfilling in front of the slope. Secondly, a series of sensitivity analyses are carried out on the pore water pressure distribution changes to the variation of the permeability magnitude of the material and leakage properties of the joint surfaces. Finally, to control the pore water pressure of the saturated jointed slope, a series of drainage systems is designed. The arrangement and length of the drains are optimised by conducting a series of sensitivity analyses on the leakage properties of the joint and the permeability of the soft rock.
Description:
This thesis aims to investigate the impact of workplace guanxi upon knowledge sharing and innovative work behaviour. Knowledge sharing and innovative work behaviour are two behavioural variables which have been linked to various positive individual and organisational outcomes. Against the changing landscape of Chinese higher education, the two behaviours are particularly important for the success of Chinese academic staff and the local universities where they work. Extant literature has demonstrated that workplace interpersonal relationships such as leader-member exchange and team-member exchange are positively associated with individual’s work behaviours, such as knowledge sharing and innovative work behaviour. However, there is a scant literature on the impact of workplace guanxi upon the two workplace behaviours. Using conservation of resource theory and social exchange theory, this research conceptualised a structural model to study the impact of workplace guanxi upon knowledge sharing and innovative work behaviour. A positivist approach with cross-sectional design and structural equation modelling was adopted to test the conceptualised model. Data were extracted from 479 academic staff of seven local universities in Guangdong Province of China, through selfreport questionnaire. A positive relationship was found between coworker guanxi and knowledge sharing. In contrast, no relationship was found between supervisor-subordinate guanxi and knowledge sharing. The relationship between coworker guanxi and knowledge sharing was fully mediated by teammember exchange and job satisfaction. In terms of innovative work behaviour, both supervisorsubordinate guanxi and coworker guanxi displayed a positive relationship with innovative work behaviour. Coworker guanxi showed a stronger relationship with innovative work behaviour than supervisor-subordinate guanxi did. The relationship between supervisorsubordinate guanxi and innovative work behaviour was direct. The relationship between coworker guanxi and innovative work behaviour was indirect, with full mediation of teammember exchange, job satisfaction and knowledge sharing. This thesis contributes to the literature on explaining the role of workplace guanxi, including supervisor-subordinate guanxi and coworker guanxi on knowledge sharing and innovative work behaviour. The study also demonstrates to higher education institute managers that the cultivation of academic staff’s workplace guanxi, and particularly their guanxi with peer academics, promotes academic staff’s displays of knowledge sharing and innovative work behaviour which are beneficial at both individual and organisational levels within the higher education context.
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:
This thesis investigated the complex role teachers play, both formally and informally, in relation to engaging and supporting student aspirations. Due to the links that have been established between aspirations and school completion and involvement in tertiary education, aspirations are important in an educational context. Yet, despite the abundance of aspiration related research, most has focused on student or parent perspectives, with few scholars targeting teacher perceptions of their roles in relation to student aspirations. This research is therefore significant as it addresses this gap through a single case study investigating perceptions of P-12 teachers from a peri-urban independent school in Victoria, Australia. Data were collected from 57 teachers via survey, interviews, and school document analysis. A lens of research-as-bricoleur, incorporating the theoretical frameworks of Bronfenbrenner (1979; 1994), Turner (2001), Gottfredson (1981, 1996), and Patton and McMahon (2015), provided the interpretative basis for the applied thematic analysis of the different data sets. Findings demonstrated differences in the way that teachers conceptualised their role in engaging with student aspirations. While teacher participants identified various formal and informal roles that they played in relation to engaging student aspirations, they also reported a lack of clear guidance or guidelines, necessitating the development of personal processes to direct their involvement. Other important findings highlighted a number of factors that teacher participants perceived as facilitating or impeding possible roles they could play in engaging student aspirations. The understandings emanating from this research provide substantive assistance to stakeholders, including school administrators and teacher educators, in appreciating and appropriately responding to an area of practice which remains misunderstood and without clear policy or guidelines. Ultimately, this research adds to the growing body of research into student aspirations and the concomitant importance of teachers in helping students aspire to and achieve their goals.
Description:
At the heart of today’s malware problem lies theoretically infinite diversity created by metamorphism. The majority of conventional machine learning techniques tackle the problem with the assumptions that a sufficiently large number of training samples exist and that the training set is independent and identically distributed. However, the lack of semantic features combined with the models under these wrong assumptions result largely in overfitting with many false positives against real world samples, resulting in systems being left vulnerable to various adversarial attacks. A key observation is that modern malware authors write a script that automatically generates an arbitrarily large number of diverse samples that share similar characteristics in program logic, which is a very cost-effective way to evade detection with minimum effort. Given that many malware campaigns follow this paradigm of economic malware manufacturing model, the samples within a campaign are likely to share coherent semantic characteristics. This opens up a possibility of one-to-many detection. Therefore, it is crucial to capture this non-linear metamorphic pattern unique to the campaign in order to detect these seemingly diverse but identically rooted variants. To address these issues, this dissertation proposes novel deep learning models, including generative static malware outbreak detection model, generative dynamic malware detection model using spatio-temporal isomorphic dynamic features, and instruction cognitive malware detection. A comparative study on metamorphic threats is also conducted as part of the thesis. Generative adversarial autoencoder (AAE) over convolutional network with global average pooling is introduced as a fundamental deep learning framework for malware detection, which captures highly complex non-linear metamorphism through translation invariancy and local variation insensitivity. Generative Adversarial Network (GAN) used as a part of the framework enables oneshot training where semantically isomorphic malware campaigns are identified by a single malware instance sampled from the very initial outbreak. This is a major innovation because, to the best of our knowledge, no approach has been found to this challenging training objective against the malware distribution that consists of a large number of very sparse groups artificially driven by arms race between attackers and defenders. In addition, we propose a novel method that extracts instruction cognitive representation from uninterpreted raw binary executables, which can be used for oneto- many malware detection via one-shot training against frequency spectrum of the Transformer’s encoded latent representation. The method works regardless of the presence of diverse malware variations while remaining resilient to adversarial attacks that mostly use random perturbation against raw binaries. Comprehensive performance analyses including mathematical formulations and experimental evaluations are provided, with the proposed deep learning framework for malware detection exhibiting a superior performance over conventional machine learning methods. The methods proposed in this thesis are applicable to a variety of threat environments here artificially formed sparse distributions arise at the cyber battle fronts.
Description:
Coal is the dominant and most reliable source of energy in Australia. However, the increasing global temperatures and its impact on the climate raises concerns on the use of coal worldwide. Due to availability of abundant, cheap quality coals, Australia is researching how it and its international customers can continue to use its abundant coal resources whilst limiting greenhouse emissions. Hence, low CO2 emitting energy technologies like carbon capture and storage (CCS) have an important role to play not only in power but also the cement and steel industries Post-combustion CO2 capture (PCC), the most developed technology in CCS using aqueous amines to capture CO2, still face challenges for its large-scale commercialisation. The cost of electricity with PCC rises to almost double that produced without integrating PCC technology in new power stations. The retrofit of PCC technology into existing power stations is very site specific and costs can be around half of the cost of building a new power plant. Apart from this, the implementation of PCC poses an energy penalty to the power station as the efficiency of the plant can drop almost by 10-11% due to the increased solvent heating and CO2 compression loads. Particularly with the nations like Australia, the cost of PCC installation is even higher as there are no flue gas desulfurisation (FGD) units in Australian power stations. The presence of harmful gases like SO2 in coal-fired power plant flue gases affect CO2 capture performance during PCC due to the higher affinity of amines to absorb stronger acidic gases against CO2 which is a weaker acid gas than SO2. These stronger acidic gases tend to form heat stable salts with the absorbent amines used to capture CO2 . Heat stable salts refer to the thermally non-regenerable protonated amines which are usually produced when the amine solution is contaminated by organic acids (Weiland et al., 2004). Hence, the bonded amine is not available for CO2 capture, increasing the requirement for makeup amine resulting in higher operating cost. Therefore, FGD units are an essential requirement before the installation of PCC facilities in a coal-fired power station. This results in a levelised cost of electricity in Australian power plants that is high compared to nations which have FGD installed in their power stations. CSIRO has developed a combined capture process to simultaneously capture CO2 and SO2 from Australian power plant flue gases using a single amine absorbent in order to lower the cost of PCC installation in Australia. The process generates a unique sulfur rich amine absorbent which needs regeneration. This thesis investigates various amine regeneration processes, using MEA as a reference, and their commercial viability to the CS-Cap process. Due to the unique nature of the sulfur rich absorbent generated in the CS-Cap process, its amine is recoverable through many other regeneration processes besides standard thermal reclamation. My thesis investigates the effectiveness of regeneration techniques like Ion exchange, Electro-dialysis, Crystallisation, Nano-filtration in regenerating the sulfur rich amine. Initially the theoretical investigation was carried as a part of literature review and further a brief exploratory laboratory scale evaluation of the most suited technologies was carried out. The results obtained from laboratory scale experimentation were fed to an Aspen Plus simulation model in order to understand the behaviour of the system under various operating conditions. Further a cost estimation was carried out in order to produce a high level cost for the selected regeneration technologies in the CS-Cap process. The cost of the regeneration technologies were further integrated into the overall CO2 capture process in order to compare the cost of standard FGD + PCC process against the CS-Cap process which answers the broader research question whether the CS-Cap process will be economical for Australian coal power plants. Overall this thesis reveals the effectiveness of various technologies in regenerating sulfur rich amines. It suggests CSIRO’s patented CS-Cap process is a cost-effective approach for capturing CO2 from Australian coal fired power plants despite its sensitivity to regeneration cost.
Description:
This PhD is the first prosopographical study of two generations of Australian manual healers in the twentieth century. The central historical figure is Thomas Ambrose Bowen (1916-1982) a self-titled Australian osteopath and arguably a therapeutic genius turned victim of health politics of the twentieth century. Bowen was stripped of his osteopathic identity as a result of political machinations that occurred during regulation of the industry in the late-1970s and early-1980s. This thesis reveals the legitimacy of Bowen’s claim to osteopathic stature and how his career is representative of the experience of a number of osteopaths during regulation of chiropractic and osteopathy. Bowen’s career was obscured in two respects. Firstly, in the lead up to the Chiropractors and Osteopaths Act 1978, overseas educated interests sought to disenfranchise Australian practitioners. This was offset by a successful response from the Australian chiropractic lobby. Secondly, posthumous commercial popularisation of Bowen’s claimed work, absent observer consensus and historical research, has further served to obfuscate Bowen’s prowess and marginalised his legacy. This thesis is the first to link Bowen’s practice to the influence of F G Roberts, an early Australian pioneer of naturopathic osteopathy. It explores Bowen’s emergence from a network of prominent football masseurs to his professional engagement with osteopathic advocates. This thesis is the first historical study to present the clinical life and times of Bowen among his contemporaries. In doing so it examines his broader significance as a consummate Australian osteopath. New historical narratives founded on extensive primary sources, oral histories as well as discourse analysis, ethnography, biography, hermeneutics and cultural mapping are used to place Bowen in context with his peers on the Australian osteopathic stage. Posthumous narratives that underpin commercial global marketing are challenged to the extent they obscure a clear historical view of Bowen and his marginalised contemporaries as unique actors in their struggle for recognition
Description:
Unbound Granular Materials (UGMs) are used in the base/subbase layers of flexible pavements for the majority of roads around the world. The deterioration of pavements increases with the increase of traffic loadings. To ensure the long-term performance and serviceability of pavement structures through a realistic design, the precise evaluation and comprehensive characterisation of the resilient and permanent deformation behaviour of pavement materials are essential. The present PhD study aims to investigate the characterisation of the resilient and permanent deformation behaviour of four road base UGMs sourced from quarries in Victoria, Australia, using Repeated Load Triaxial (RLT) testing. The triaxial system used in this study is instrumented with four axial deformation measurement transducers to achieve highly precise measurements and to evaluate the effect of instrumentation on the resilient modulus of UGMs. The resilient Poisson’s ratio of the studied UGMs is also determined using a radial Hall-Effect transducer. Moreover, a series of permanent deformation tests is performed to precisely characterise the axial and radial permanent deformation behaviour of UGMs and investigate the factors that may significantly influence the accumulated axial and radial permanent deformations. Finally, three permanent deformation models incorporated with a time-hardening procedure are employed to predict the magnitude of permanent strain for multiple stress levels of the RLT test. The predictions using the employed models are then compared against the measured values to evaluate the suitability of the models and to identify the model that best predicts the strain accumulation behaviour of the tested UGMs. While this study focuses on the resilient and permanent deformation behaviour of four Victorian UGMs under repeated loading, the knowledge generated from this comprehensive investigation will contribute towards the global development of more reliable methods for evaluating the long-term performance of pavement structures and minimising road maintenance and repair costs.
Description:
Unbound Granular Materials (UGMs) are used in the base/subbase layers of flexible pavements for the majority of roads around the world. The deterioration of pavements increases with the increase of traffic loadings. To ensure the long-term performance and serviceability of pavement structures through a realistic design, the precise evaluation and comprehensive characterisation of the resilient and permanent deformation behaviour of pavement materials are essential. The present PhD study aims to investigate the characterisation of the resilient and permanent deformation behaviour of four road base UGMs sourced from quarries in Victoria, Australia, using Repeated Load Triaxial (RLT) testing. The triaxial system used in this study is instrumented with four axial deformation measurement transducers to achieve highly precise measurements and to evaluate the effect of instrumentation on the resilient modulus of UGMs. The resilient Poisson’s ratio of the studied UGMs is also determined using a radial Hall-Effect transducer. Moreover, a series of permanent deformation tests is performed to precisely characterise the axial and radial permanent deformation behaviour of UGMs and investigate the factors that may significantly influence the accumulated axial and radial permanent deformations. Finally, three permanent deformation models incorporated with a time-hardening procedure are employed to predict the magnitude of permanent strain for multiple stress levels of the RLT test. The predictions using the employed models are then compared against the measured values to evaluate the suitability of the models and to identify the model that best predicts the strain accumulation behaviour of the tested UGMs. While this study focuses on the resilient and permanent deformation behaviour of four Victorian UGMs under repeated loading, the knowledge generated from this comprehensive investigation will contribute towards the global development of more reliable methods for evaluating the long-term performance of pavement structures and minimising road maintenance and repair costs.
Description:
Coode Island Silt (CIS) is one of the predominant geological units in Melbourne, Australia. Having high compressibility and low shear strength, CIS is considered a problematic soft soil that challenges the construction of infrastructure in the region. To tackle such challenges, one practical approach is the application of ground improvement techniques such as in situ soil mixing. This PhD study focuses on the application of Cutter Soil Mixing (CSM) for the construction of excavation retaining walls in CIS. Although cement is widely used in most CSM projects, this study investigates the suitability of different lime types available in the Australian market as a potential alternative to cement for the stabilisation of CIS. To investigate the effect of lime stabilisation, a comprehensive geotechnical characterisation of untreated and lime treated CIS is performed. Four different lime types are used: agricultural lime, quicklime, hydrated lime and slag lime. Based on the results obtained from strength tests, slag lime was found to be the most effective among the four types that were tested. The optimum slag lime to CIS ratio is then found for the construction of retaining walls in CIS. Having the geotechnical characterisation of untreated and treated CIS from the laboratory experiments, a series of two-dimensional and three-dimensional finite element method (FEM) analyses were conducted to investigate the applicability and reliability of the selected mixing ratio for the construction of CSM excavation retaining walls in CIS. A nonlinear constitutive soil model was employed, calibrated and verified to be used in FEM analyses to investigate both the stability factor of safety and excavation-induced deformations. The results obtained for both undrained and fully coupled flow deformation analyses prove that CSM panels can be constructed by mixing slag lime and CIS to act as retaining walls to allow for deep excavation in CIS.
Description:
This practice-led research explores questions of interspecies empathy, mutuality and kinship within the context of visual art. The study is situated broadly within the cross-disciplinary field of Animal Studies and espouses an animal advocacy stance within contemporary arts practice. It addresses concerns about the role of animals in contemporary art and proposes that creating art should not subordinate the ethical treatment of animals. The parameters of this investigation are defined by empathy theory, or Einfühlung. This was deemed an appropriate foundation to underpin the research given its historical association with aesthetic perceptions of works of art as well as empathic responses to other living entities including non-humans. Einfühlung and other contributing conceptual frameworks, including compassionate conservation and animal individuality are thoroughly evaluated in a review of relevant literature. Current arts practice in which the ‘animal’ plays a role is critically examined. The consequences for animals in contemporary art are more often malign than benign and this contrasts with progressive thinking about animal sentience in other areas of philosophical research. In a distillation of the above theoretical concepts, the research further references issues relating to selective application of care for non-human animals, in which the level of consideration is often dependent on human perceptions of the creatures’ status, for example native or introduced animals. The results of the research were revealed through a body of practical work including sculpture, collage, prints and artists’ books which depict a variety of animals and birds, both native and non-native, encountered as part of everyday experience; a visual exploration in which human-perspective classification of animals does not play a part.
Description:
The main objective of this research is to investigate and implement a robust approach with a view to provide the Law Enforcement Agencies (LEAs) with a dedicated forensic tool in future for inspecting confiscated PCs from the suspected paedophile to detect pedophilic images automatically and prevent children viewing pornographic and age-inappropriate images at their home and school and adults at their workplace while they are on the Internet. To achieve this goal, we use a novel face descriptor to differentiate child face from adult face based on categorical age specific contextual cues that are based on new knowledge in terms of features or contexts representatives of child and adult face. Given that the craniofacial cues contain enough structural information on visual cues on human face encoded in the form of high level features we can categorize age into adult and children in tandem with low level features. Finally, we will present a novel stochastic vision model based on Markov Random Fields (MRF) prior, which learned the pornographic contextual constraints from the training pornographic images and eventually introduce knowledge on pornography into our proposed stochastic classifier allowing classification of images into pornographic or benign.
Description:
Data mining is about solving problems by analyzing data that present in databases. Supervised and unsupervised data classification (clustering) are among the most important techniques in data mining. Regression analysis is the process of fitting a function (often linear) to the data to discover how one or more variables vary as a function of another. The aim of clusterwise regression is to combine both of these techniques, to discover trends within data, when more than one trend is likely to exist. Clusterwise regression has applications for instance in market segmentation, where it allows one to gather information on customer behaviors for several unknown groups of customers. There exist different methods for solving clusterwise linear regression problems. In spite of that, the development of efficient algorithms for solving clusterwise linear regression problems is still an important research topic. In this thesis our aim is to develop new algorithms for solving clusterwise linear regression problems in large data sets based on incremental and nonsmooth optimization approaches. Three new methods for solving clusterwise linear regression problems are developed and numerically tested on publicly available data sets for regression analysis. The first method is a new algorithm for solving the clusterwise linear regression problems based on their nonsmooth nonconvex formulation. This is an incremental algorithm. The second method is a nonsmooth optimization algorithm for solving clusterwise linear regression problems. Nonsmooth optimization techniques are proposed to use instead of the Sp¨ath algorithm to solve optimization problems at each iteration of the incremental algorithm. The discrete gradient method is used to solve nonsmooth optimization problems at each iteration of the incremental algorithm. This approach allows one to reduce the CPU time and the number of regression problems solved in comparison with the first incremental algorithm. The third algorithm is an algorithm based on an incremental approach and on the smoothing techniques for solving clusterwise linear regression problems. The use of smoothing techniques allows one to apply powerful methods of smooth nonlinear programming to solve clusterwise linear regression problems. Numerical results are presented for all three algorithms using small to large data sets. The new algorithms are also compared with multi-start Sp¨ath algorithm for clusterwise linear regression.
Description:
Medium sized workplaces are often grouped with small enterprises, yet they can have unique characteristics compared to more intensively studied small and large organisations, however, these differences are often not clearly recognised. The food processing industry is often part of the small and medium sized enterprises (SME) group and has a higher rate of accidents, injury and disease compared with many other industry groups. To improve safety performance in medium enterprises (within the food processing industry), there is a need to identify the perceived barriers to improving OHS amongst managers, supervisors, and process workers. This research provides a unique insider’s point of view of a food packing room within a food manufacturing plant in Melbourne. It is a single case design study, focusing on a specific medium sized enterprise, using insider research and an ethnographic approach to gain a greater understanding of the perceived barriers to improving OHS. The first part of this research focused on understanding the safety culture of the organisation, from different hierarchical perspectives, using Hudson’s Evolution of Safety Cultures model. The second part utilised the Health Belief model to identify the barriers to improving OHS from multiple perspectives of managers, supervisors and process workers. Following the analysis of the results, five barriers were identified: (i) fragmentation of group perspectives; (ii) poor communication between and within the hierarchical groups; (iii) limited OHS training and competency; (iv) inadequate management commitment to OHS; and (v) lack of empowerment. This created tensions amongst and between the groups. However, further examination of these findings suggested a deeper reason for the difficulty in improving the OHS, which was affecting the organisation. The most significant barrier to improving OHS at this workplace was the learned helplessness that had developed over a period of time and had filtered through all hierarchical groups. A reflection on the choice of methodology (insider research) and the importance of ethical considerations and the depth of meaning that was drawn from this research has been presented in this thesis. Learned helplessness has been discussed in the context of a medium sized enterprise and its significance to the contribution to OHS literature. Recommendations have been provided in terms of addressing learned helplessness within a medium sized enterprise, by changing the way individuals think, using learned optimism. Other changes that have been presented have included organisation design, facilitating improved communication and goal setting, and the investigation into the supporting role of supply chains toward OHS initiatives.
Description:
"Longitudinal studies, where data is collected by measuring the same experimental units several times over a relatively long period, are becoming increasingly common. Conventional statistical approaches have limitations when applied to the analysis of longitudinal data ... Practical limitations of longitudinal analysis that relate to missing data and large data set sizes were explored in this thesis with the application of a sampling technique known as Ranked Set Sampling (RSS). We developed this sampling method, which has not previously been applied to longitudinal data, for fixed and mixed-effects models. This thesis also illustrated inference techniques to estimate these models after selecting sample units by RSS."