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Prioritization Model for Road Pavement Maintenance Fund Allocation Considering Cross Assets
No full textA well-maintained transportation infrastructure system dictates the hallmark of a well-functioning economy. Roads are the backbone of land transportation, sustaining the socio-economic connection from urban economic hubs to rural farmlands. Due to the huge demand for road assets, their condition deteriorates mainly because of ongoing traffic loads and environmental factors. The condition of the road asset is highly dependent on other road-related assets such as bridges and water pipes, and therefore, they are often considered together in a cross-asset system. Thus, maintenance activities on one asset can enhance the degradation of other assets in the system. The present study considers road pavements and water pipes as the two assets in a cross-asset system. In the traditional approach, the maintenance of these two assets is planned individually without considering the degradation of the other. This enhances maintenance induced-asset deterioration on the cross-asset system and results in frequent asset interventions leading to extra burden on the economy of the country. Since there is a constrained budget allocation for the maintenance of these two assets infrastructure, an integrated framework for cross-asset maintenance is required to utilize the available limited budgets optimally. Therefore, main aim of this research was to develop a prioritization framework to support fund allocation decisions of road asset managers considering an integrated approach of cross assets (roads pavement and water pipes) using collected monitoring data, calibrated degradation modeling tools, and expert surveys. Phase one of the research was planned to identify the critical assets for the study of cross-asset systems based on the discussions with the asset management authorities and published literature. Accordingly, water pipe asset was identified as the most influential cross asset for the maintenance of the road pavement asset. In the first part of Phase 2 of this study, it was aimed to develop degradation prediction models for unsealed roads based on the field data and to identify the optimum intervention strategy for unsealed roads. The field data collections were conducted over a period of 12 months, selecting two unsealed roads in Sri Lanaka to derive the gravel loss (GL) and unpaved road condition index (UPCI) parameters. The field observed GL values were compared with available deterministic models. Then, Markov-based probabilistic degradation prediction was conducted for GL and UPCI indices followed by a cost prediction and a life-cycle prediction. The results revealed that the probabilistic Markov method can be more appropriate to model the GL and UPCI deterioration of unsealed roads than the deterministic models. Furthermore, the UPCI-based method was identified to be more reliable for condition assessment, cost prediction and life cycle predictions on unsealed roads. A 5-years intervention period without allowing the road to reach the failure condition was identified as the optimum intervention strategy for unsealed roads. In the second part of Phase 2 of this study, degradation prediction models were developed for sealed roads and optimum maintenance strategies were identified. The analysis was based on a 15-year historical pavement condition survey data collected over a portion of the Australian national road network, selecting the international roughness index (IRI) as the critical parameter. This involved classification of road data into homogeneous categories based on the pavement maintenance category (PMC), region (urban or rural) and surface material (asphalt or spray seal), evaluation of the effect of different environmental factors on IRI distribution and developing Markov-based probabilistic degradation prediction and life cycle analysis. The outcomes of the study revealed that spray seal roads exhibited high deterioration compared to Asphalt surfaces. The ‘regulation + resurface’ maintenance at trigger condition level 4 was identified as the optimum intervention for sealed roads. The third phase of the study aimed to develop an optimum fund allocation strategy for a cross-asset system by combining the maintenance of the road asset and the water pipe asset. The Analytic Hierarchy Process (AHP) was used for the prioritization of the asset groups (roads and water pipes), asset elements (within each group), and maintenance activities, considering the critical criteria for the maintenance. Inputs for these AHP developments were collected through two questionnaire surveys conducted among the asset management experts in the field of road asset maintenance and water pipe asset maintenance. This study was followed by two case studies in Sri Lanka and Australia, and the optimum combinations of the intervention levels for each element in the asset system were identified, considering the available budgets. A trade-off analysis was conducted in these case studies, and the optimum maintenance strategy for the integrated multiple-asset system was determined by comparing the cost values and the benefit (condition improvement) to cost ratio. From these studies, it was revealed that the fund allocation ratio among roads and pipe assets in a cross-asset project is 0.7:0.3 in Sri Lanka and 0.58: 0.42 in Australia. Phase 4 of this research was designed to develop a framework for the maintenance prioritization of cross-asset projects falling under the same budget. In this framework, the ranking was decided based on the priority value ‘Overall asset maintenance rating’ (OAMR), which is a measure of the overall maintenance requirement of the considered asset system. OAMR was calculated by combining the asset maintenance ratings (AMR) of each individual asset group (road and water pipe asset groups) and it represents the average rating value for the entire project corridor. AMR value combines the performance indicators related to asset condition and asset value (including risk analyses) for each asset group. Overall, the framework assessed the actual maintenance priority of the project considering the physical conditions and financial risks associated with the assets in the project. The proposed method was applied to a case study in Australia, and the selected maintenance projects were ranked based on the OAMR values. The findings of this study could be applied to intelligent asset maintenance models to evaluate the absolute maintenance requirement of a project and to compare it with the other projects for the prioritization of the fund allocations. Overall, this research identifies optimum maintenance strategies for unsealed and sealed road pavements through probabilistic degradation prediction and life cycle analysis. Based on the optimum maintenance strategies for individual assets, road assets and water pipe assets were integrated for maintenance planning to achieve the optimum utilization of limited maintenance budgets. Further the OAMR rating system facilitates the prioritization of road related cross asse projects by combining the asset condition-based performance indicators with the asset value-based performance indicators. The outcomes and the developed framework could be implemented in asset management platforms to assist in decision making related to road asset maintenance considering water pipes as a critical cross asset.</p
Resilin-mimetic Polypeptides: Biosynthesis and Structure-Function Correlation
No full textIntrinsically disordered proteins (IDPs) belong to a unique type of proteomes that show various structural subtypes as they lack a three-dimensional structure. These proteins stand out amongst their neighbours, forming the core for cellular activity and signalling networks whilst in a highly disordered state. This is possible through interactions that arise from specific monomeric sequences within a broad amino acid sequence that reflect unique functional properties, which include a wide range of stimuli-responsiveness. Resilin is one such IDP, well-known for its prolific elastomeric nature and unique multi-responsive behaviours, including a highly uncommon dual phase behaviour (DPB). Despite the protein being an attractive IDP to utilise, it presents a few limitations which restrict its ability to expand its potential use in applications. For instance, resilin is a highly hydrophilic IDP, making it lack any cell recognition/binding sites, where its lower critical solution temperature (LCST) occurs at ~ 70°C, which restricts the exploitation of the protein for applications that can utilise such phase behaviour such as drug delivery or injectable applications. Therefore, the ability to modify the IDP to address such constraints could amplify the potential of the already attractive elastomeric protein. However, the niche of understanding the fundamental mechanisms behind such IDPs is still in its infancy, as it is difficult to evaluate their disorder-function relationship compared to the classic structure-function model of proteins. Thus, in-depth analysis is required, where advanced techniques can aid in grasping information that develops a consensus of understanding compositions of IDPs and their corresponding disorder-function relationship. Recent studies have highlighted how embarking on a biomimetic approach to artificially design and develop biomaterials can form distinctive and fascinating biomaterials. Despite this route being an attractive method to pursue, there are many unknowns regarding the fundamental molecular impact of such biomaterials. This includes various complications that can arise during the design and synthesis of such IDPs, compared to the facile chemical synthesis approach, which cannot be utilised for this purpose. A biomimetic modular approach to developing IDPs requires intricate molecular tuning, with the selection of monomeric sequences (utilising a recombinant DNA strategy). However, understanding the roles of the interaction of these amino acids is yet to be fully recognised either. Thus, identifying the most useful sequences, tailored for the desired biomimetic IDP, displaying high levels of functionality with the ability to be controlled/tuned and utilised for a multitude of applications, creates an opportunity to explore uncharted territories. Analogously, co-assembled systems follow a more simplistic approach, where supramolecular complexes can be developed by carefully selecting biomaterials based on their amino acid composition. Previous work with resilin has successfully reduced the LCST of resilin with a rigid polypeptide or a hydrophobic protein. However, IDP co-assembly is still nascent, where unique approaches and advanced experimental characterisations are still required to investigate the interaction between the IDP and selected biomaterial, which creates new opportunities to understand how IDPs can be tuned without losing their inherent function. In that regard, exposing these IDPs to realistic environmental crowders provides fresh insight into perceiving the interactions and structural dynamics in crowded states, where such investigation remains unresolved, as these IDPs exhibit an ultrafast motion. Finally, as resilin exhibits an LCST, it shows a coacervation mechanism transitioning from a liquid-like to a solid-like state, which can be utilised for surface and internal body applications with the possibility of switch ability for cell-surface interactions. Yet, this phenomenon has not been fully explored, where there is limited understanding of the protein in a coacervate state and any interactions and resulting physico-chemical properties and functionalities exhibited. In light of the above challenges and needs, it is hypothesised that resilin-mimetic polypeptides (RMPs) designed and developed through various strategies will create a platform for understanding the disorder-function relationship and tunability of IDPs. Thus, four different biomimetic approaches were availed for this research study, entailing a (i) novel recombinant DNA modular protein engineering approach, (ii) facile co-assembled perspective, (iii) exposure of RMPs in a crowded state and (iv) bioengineered surfaces through various RMP systems including a resilin-mimetic nano-coacervate coating. In such manner, two novel modular RMPs designed and developed could retain the intrinsically disordered nature of resilin through the addition of a domain, compared to the widely explored route of substituting amino acids for a modular approach. The modular RMPs could further exhibit the DPB of resilin and display tuneability by reducing the LCST of native resilin. Consequently, a very low fouling biomimetic material transpired, which has vast potential to be further modified and create a platform for designing and developing IDPs. Analogously, a dynamic co-assembled resilin-based system incorporating a hydrophilic adhesive protein was formed, where the DPB was once again retained and tuned to lower the LCST. Adding the hydrophilic protein to the IDP improved its shelf-life stability, creating an interconvertible β-sheet structure. Exposure of the IDP to a crowded environment indicated that the overall secondary structural nature is marginally affected by the type of crowder and its quantity. Thus, suggesting IDP characteristics were reserved by evading crowder-induced folding despite interaction by evaluation of advanced techniques and modelling. Thus, creating a model to understand IDPs' conformal dynamics and stimuli-responsiveness in realistic environmental conditions. Finally, a nano-coacervate resilin-based coating was fabricated amongst other resilin-mimetic nano-coatings. The nano-coacervate showed a nanostructured switchable responsive surface that could modulate biofilm formation and antibacterial characteristics, showing vast potential in biomedical devices and applications, including implants and drug delivery. This thesis thereby contains seven chapters comprising published journal papers, experimental characterisations and manuscripts prepared/submitted for journal submission/publication. Accordingly, each chapter (excluding the experimental and conclusion/future recommendations chapters) corresponds to its relevant manuscript. In that respect, the idea of understanding the artificial production, correlation of structure and function relationship of engineered biomimetic resilin protein-based systems is explored through literature in the introductory chapter, followed by an experimental section, which leads to the investigation chapters and finishes with a conclusion and future recommendations.</p
Benefits of Stainless-Steel Material in Rectifying Local Identity in Public Sculpture
No full textIn the past decade, stainless steel has become an increasingly popular material for public sculptures, substantially contributing to the modification and improvement of community identities. This article aims to investigate the several advantages that stainless steel may bring to public art, with a particular emphasis on the metal’s aesthetic, practical, and symbolic effects. Aesthetically, stainless steel is a versatile medium that can generate a broad variety of surfaces and forms, allowing it to reflect and intensify the visual identity of a community. Its long-term durability, resistance to corrosion, and low maintenance requirements make it an excellent option for public installations subjected to various environmental conditions. Symbolically, stainless steel represents modernism, robustness, and sustainability, aligning with the contemporary ideals and goals of local communities. This article seeks to demonstrate, using an artistic research approach, how stainless-steel sculptures function not only as creative expressions but also as essential components in the process of place-making, generating a sense of pride and belonging among people. The incorporation of stainless steel into public sculpture is therefore a crucial factor in forming and revitalising local identities in urban settings.</p
Characteristics and Performance of Ceramic Tiles Incorporated with Recycled Wastes
No full textThe management of municipal solid waste (MSW) is a growing global environmental challenge. According to the World Bank, annual global MSW production reached 2.01 billion tonnes in 2016 and is projected to rise to 3.40 billion tonnes by 2050. Among various waste items, cigarette butts (CBs) are one of the most littered, posing severe environmental threats due to poor biodegradability and the release of toxic chemicals. With an annual consumption of 5.7 trillion cigarettes and a 75% littering rate, effective recycling methods for CBs are crucial.In addition to CBs, this study also focuses on recycling fly ash from waste incineration, another significant waste by-product. Incineration reduces waste volume and allows for energy recovery but produces fly ash containing heavy metals and soluble salts. This research examines recycled paper production boiler fly ash, similar to municipal solid waste incineration (MSWI) fly ash but containing large amounts of waste paper fibres. Due to variances in waste composition, incineration equipment, and methodologies, the chemical makeup of these wastes also varies. Therefore, fly ash is analysed as two distinct waste types: MSWI FA from facilities processing more municipal solid waste in Victoria, and IWA from facilities processing more construction and demolition waste in Queensland.This innovative study investigates the potential of using CBs, MSWI FA, and IWA as substitutes in ceramic tile production, aiming to promote sustainable practices in the ceramics industry by converting waste materials into valuable resources. Experimental trials integrated these waste materials into ceramic tiles in varying proportions, evaluating the balance between environmental benefits and the functional quality of the tiles. Comprehensive assessments included physical, chemical, and mechanical properties, as well as detailed analyses like microanalysis, heavy metal leaching, energy consumption, thermal behaviour, and life cycle assessment (LCA). The aim was not merely to alter tile composition but to offer a novel perspective on resource use and sustainability in the ceramics industry.Key findings include:• Incorporating CBs in ceramic tiles increased water absorption at higher CB content but complied with Group III (Ev >10%) wall tile criteria. Tiles with 0.5% CB content showed improved bending strength (from 15.56 MPa to 16.33 MPa) and potential energy savings compared with control sample tiles.• MSWI FA was successfully used in enhanced tile formulations and manufacturing processes, meeting the Group BIIa floor tile requirements (3% • IWA was examined as a substitute for potassium feldspar, with up to 30% IWA incorporation producing high-performance tiles (Ev= 5.9% and MOR= 30 MPa) and substantial estimated energy savings (33.86%) when fired at 1300 °C. IWA also enhanced thermal conductivity, making tiles suitable for underfloor heating systems. The LCA highlighted significant reductions in environmental impacts, including decreases in terrestrial ecotoxicity (22.47%), terrestrial acidification (10.09%), and climate change impacts (8.49%) for 30% IWA tiles.These findings demonstrate the feasibility and environmental benefits of incorporating waste materials in ceramic tile production, offering sustainable, performance-enhancing, and cost-effective alternatives. Waste materials can replace traditional ceramic raw materials, contributing to waste reduction and resource efficiency. Further optimisation of material proportions and processing conditions is necessary to maximise the potential of these recycled materials in the ceramic industry. This research contributes to sustainable materials and waste management in ceramic tile production, aligning with global efforts towards environmental protection and sustainable development.</p
Social research supporting activation of Retarding Basins for recreation: Baseline assessment of the Truganina Swamp in Altona. A Melbourne Water and RMIT Partnership Project.
No full textIn 2024, researchers at the Centre for Urban Research, RMIT University, completed baseline observational and intercept survey research at the Truganina Swamp in Altona which is a Melbourne Water Retarding Basin being considered for enhanced public access. The overall aim of this research project was to provide evidence of current community use of the site and inform the design of any potential upgrades or restoration activities.</p
The Role of Atomic Structure in Imperfect Josephson Junctions
No full textJosephson junctions are key components of superconducting qubits, which are one of the most promising candidates to realise large-scale quantum computing. The performance of these qubits is limited by our understanding of the materials science of Josephson junctions. Imperfections in the materials of Josephson junction devices are a source of energy dissipation, decoherence, parameter drift, and uncertainty. We utilise an atomistic model of Al-AlOx-Al Josephson junctions as a method to study pinhole imperfections in the oxide tunnel barrier. With the non-equilibrium Green's function formalism we study quasiparticle transport through devices, and extend these methods to study the superconducting current-phase relationship using two different approaches. Additionally we study a recently developed alternating bias assisted annealing technique computationally to understand its effect on atomic movement within the barrier, and device parameters such as the normal resistance and critical current. This work aims to provide insights to inform and optimise the fabrication processes of Al-AlOx-Al Josephson junctions, supporting advancements in quantum computing technology.</p
Textual emotion detection – A systematic literature review
No full textTextual emotion detection is a critical area of study with significant applications in business, education, and healthcare. Despite substantial theoretical advancements over the years, there is a notable gap in the practical implementation of these methods in the aforementioned fields. The techniques currently available do not yet seem ready for real-world application. This study offers a comprehensive review of existing approaches, datasets, and models used in textual emotion detection. Its primary objective is to identify the challenges faced in both current literature and practical applications. The findings reveal that textual datasets annotated with emotional markers are scarce, making it difficult to develop robust supervised classification models for this task. There is also a pressing need for improved models that can accurately categorize a wider range of emotional states distinctly. Finally, there is a demand for techniques capable of dimensionally detecting valence, arousal, and dominance scores from emotional experiences. These challenges stem not only from the models and applications themselves but also from the readiness of current approaches and datasets in the rapidly evolving fields of machine learning and affective computing.</p
Optimising the manufacturing of a β-Ti alloy produced via direct energy deposition using small dataset machine learning
No full textSuccessful additive manufacturing involves the optimisation of numerous process parameters that significantly influence product quality and manufacturing success. One commonly used criteria based on a collection of parameters is the global energy distribution (GED). This parameter encapsulates the energy input onto the surface of a build, and is a function of the laser power, laser scanning speed and laser spot size. This study uses machine learning to develop a model for predicting manufacturing layer height and grain size based on GED constituent process parameters. For both layer height and grain size, an artificial neural network (ANN) reduced error over the data set compared with multi linear regression. Layer height predictions using ANN achieved an R2 of 0.97 and a root mean square error (RMSE) of 0.03 mm, while grain size predictions resulted in an R2 of 0.85 and an RMSE of 9.68 μm. Grain refinement was observed when reducing laser power and increasing laser scanning speed. This observation was successfully replicated in another α + β Ti alloy. The findings and developed models show why reproducibility is difficult when solely considering GED, as each of the constituent parameters influence these individual responses to varying magnitudes.</p
Crafting Kuweni’s Legacy: Folklore-Inspired Responsible Dyeing Techniques and Textile Developments
No full textFolklore, originating from the past, holds immense social and cultural significance, forging profound connections with communities’ roots. This study examines into the folklore of Kuweni in Sri Lanka, revealing its historical and geographical significance intertwined with myth. The story of Kuweni, a young native woman from diverse local communities, has spawned various place legends, with Thambappanni being particularly noteworthy in this folklore. The aim of this research is to explore the translation of folklore elements into a localized fashion products that honour the narrative, and connect past and present. By adopting a thematic approach to analyse folk literature and the folklore of Kuweni, this study takes a practice-led approach to fashion product development. In the conceptualization phase, it highlights the unique aspects of the place legend, Thambappanni, famous for its copper-coloured soil and Kuweni’s tale of spinning cotton for handloom weaving in this region. This led to experiments in handloom weaving using yarn dyed with a specific technique derived from Thambappanni soil, resulting in a distinct textile product deeply rooted in folklore and to ideas of fashion localism. The significance of these findings lies in the conceptual framework developed for transforming folklore into fashion products, bridging the preservation of socio-cultural values from folklore to contemporary society through fashion that speaks to the significance of place and story.</p
Internship crafting: Transposing the concept of job crafting for students undertaking work-integrated learning
No full textThis paper proposes internship crafting as a strategy for addressing a range of challenges encountered by students,
host organizations, and educators involved in the planning and undertaking of internships. Challenges include
work that lacks relevance to students’ aspirations, host organizations’ difficulty in judging the amounts and types
of work to provide, and educators’ uncertainty regarding how to support the required negotiations. Internship
crafting is explored as an opportunity to position students as active agents in the design of their internship
experiences. The concept draws on the idea of job crafting, by which employees proactively co-design their tasks
with colleagues and superiors to better align their strengths and interests with the needs of their organizations, for
mutual benefit. Transposing job crafting onto internships creates a framework with the potential to empower
students to co-design their internship experiences to advance both the needs of their host organizations and their
own professional growth.</p