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Effect of dwell time on consensus in multiagent systems with time‐varying topologies
No full textThis paper studies the effect of dwell time on consensus of high‐order multiagent systems with time‐varying topologies. In contrast to existing literature that only focuses on the convergence of consensus, the proposed work focuses on the sensitivity of consensus on the dwell time and studies its relationship with consensus behaviors. In particular, it is shown that dwell time determines the duration of agent interactions, resulting in different state dynamics, consensus values, and convergence speeds under different switching topologies. Such effects can impact the dynamical performance of the multiagent systems. To quantitatively analyze the effect, a procedure is proposed to estimate the consensus values with respect to the dwell time and switching topologies, and a condition is obtained to find the topologies that can speed up the convergence. The proposed study is applied to the regulation of microgrids, which proves to be effective in improving the performance and efficiency of controllers.</p
A Customisable LED System for Standardised Photobiomodulation Research Using Advanced Skin Modelling
No full textRecently renewed scientific and commercial interest in the medical applications of non-ionising radiation have illuminated the potential therapeutic benefits of visible light, particularly within the red to near-infrared spectrum. However, laboratory-based studies have yielded contradictory findings which led to commercially produced therapeutic devices (various hand-held devices and wearables) to generate conflicting outcomes in patient treatments. Therapies have revealed mixed results varying from profound positive, negligible, to detrimental effects.Skin response to photobiomodulation (PBM) is of particular interest due to the limited penetration of visible light, and promising results have been shown to accelerate wound healing, reduce signs of aging and assist in acne management. While observed biological effects are promising, inconsistencies throughout the literature are caused, in part, by a lack of standardisation and limited understanding of the targeted molecular mechanisms, which shroud the field in uncertainty. This is particularly true of very low intensity light exposures (This PhD project has three key aims: (i) to design and fabricate a modular exposure system to provide reliable and repeatable visible light irradiation of cells in a standard well plate, (ii) to investigate the mechanisms of action deep red light modulates skin cell behaviour through, and (iii) to develop a more advanced epidermal in vitro skin model. First, a novel LED exposure system with interchangeable LEDs was designed and fabricated. The modular system allows for light of different wavelengths and intensities to be delivered to individual wells in a standard 24-well cell culture plate by swapping out LEDs or adjusting the current supplied. The device was used to expose skin cells (HaCaT cells derived from human epidermal keratinocytes) to visible light with wavelengths of 585 nm, 610 nm, and 660 nm, at intensities ranging from 3.7 to 31 mJ/cm². An increase in cell proliferation and decreased scratch area for all exposure conditions were observed. However, only 660 nm light increased mitochondrial activity, with a fold change of 1.17±0.57 (PFurther investigations into the effect of 660nm light on skin cell mitochondria and protein expression were conducted to elucidate a possible mechanism behind the observed extremely low intensity deep red light effects. A transient increase in ATP production was observed for the first 24 hrs post exposure (with ATP nearly doubled at 6 hrs in exposed HaCaT compared to a non-exposed control) before returning to baseline by 48hrs post exposure. Following this, MitoTracker™ and JC-1 stains were used to observe any changes in mitochondrial content or membrane potential, and western blots were used to check for the expression of key mitochondrial proteins (COX IV, mitofusin, porin). However, there were variations across experiments, potentially due to the very low exposure doses, leading to inconclusive findings. To further understand the interaction between deep red light exposures and human skin tissue, a 3D printable platform to culture epidermal keratinocytes at the air-liquid-interface (ALI) was developed. Taking inspiration from the microneedle array patches used for transdermal drug delivery, the concept was flipped to deliver cell culture media to the basal layer of a 3D skin tissue model. For skin modelling, exposure of the outermost epidermal layer to air plays an important role in stimulating epidermal differentiation and encouraging barrier formation comparable to native tissue. The proposed platform comprises of a lower chamber that acts as a reservoir for cell culture media, with needle-like channels extending into a hydrogel, which mimics native skin extracellular matrix, where cells can be embedded and grown on top. The channels effectively connect the media reservoir to the hydrogel, allowing nutrients to diffuse through the hydrogel and maintain cells. Spatial control over nutrient delivery to the epidermis was shown to be modulated by changing the number and location of connections between the platform and hydrogel. Furthermore, HaCaT growth on different hydrogels (Collagen, Vitrogel®, and GelMA) was compared. HaCaT struggled to adhere or grow on GelMA, while Collagen and Vitrogel® were comparable until 72 hrs post-seeding where collagen metabolic activity was recorded to be 1.7x greater compared to Vitrogel®. This platform aims to bridge the gap between 2D cell cultures and the complex native skin environment, thereby offering a more physiologically relevant model for studying light-skin interactions.</p
Code Comprehension for Novices with Explicit Instruction
No full textProgramming is a skill that is needed by more and more people, it is no longer just for software engineers but for many varied occupations. So the background knowledge and experiences of people requiring programming skills is now quite broad. Currently, many people struggle to learn programming skills from current methods of teaching even for some learners who put in extreme mental effort. The main activity that programmers spend time and effort on is comprehending code, yet new programmers often struggle to acquire these skills.We aim to contribute to the effective instructional design of programming lessons for people without prior programming knowledge. By adopting and testing a pedagogical approach from general education research known as explicit instruction. Explicit instruction teaching practices appear to be different from typical teaching methods for new programmers.We performed a series of experiments comparing instructional design elements from explicit instruction in the context of programming lessons for new programmers. The experiments evaluated teaching code comprehension using explicit instruction elements, such as presenting smaller amounts of new material, starting with concrete tasks, and offering fully modelled skills before problem solving. These methods were tested on a broad sample of individuals without programming skills, addressing wider programming needs beyond university-level courses.Our evidence shows that the rate of success during lessons was improved by initially presenting smaller amounts of new material and staying with concrete tasks. Learners' depth of understanding was similar whether fully modelled skills were provided or not, but providing these skills led to higher success rates, as confirmed by previous programming education studies.We found ways of teaching that were beneficial to a broad set of learners, improving their chance of understanding and being able to apply code comprehension skills. These accessible teaching methods may help to improve the equitable access to people seeking or requiring programming skills.In addition to improving methods of teaching code comprehension to novices, the explicit instruction approach holds future promise. Our findings conceptually replicate past findings from explicit instruction research outside of programming education, suggesting that explicit instruction holds more promise for improving programming education outcomes for anyone who wants to learn.</p
Beyond individual skills: cultivating competence synergies in Thai automotive production
No full textPurposeProduction employees and their competences are pivotal in the generation of value and shaping human resource management strategies for small and medium-sized manufacturing enterprises (SMEs) operating within the supply chain. This study aims to understand and model how individual competences of production employees are developed and utilized within SMEs in the Thai automotive sector, highlighting the role these competences play in enhancing organizational competitiveness.Design/methodology/approachEmploying a grounded theory methodology, this study analyzes data from in-depth interviews with 30 participants—10 owners and 20 production employees. The research systematically categorizes competences and investigates their synergistic effects on organizational performance.FindingsThe result identifies key competences of production employees, such as inquisitiveness, functional, emotional intelligence, and integration competences. It is found that these competences, when combined, lead to synergistic effects that have the potential to enhance employee performance and organizational efficiency.Originality/valueThe study provides novel insights into the competence-based theory of firm competitiveness in emerging markets by demonstrating how individual competences of production employees interact to produce greater collective capabilities within SMEs.</p
Morphology of Kinesis
No full textBackground Recent scholarship in sound studies, human–computer interaction, and biophilic design shows that interactive media can breach the gap of equitable distribution of access to the emotional benefits of environmental closeness, simulating feelings related to in-nature experiences. Applying deep reflection on the nature-related sustainable social justice and equal access to nature, we ask: How can audiences access restorative, nature-centred experiences without the carbon cost of conventional digital installations? How to engage local and international communities in searching for ways of creative expression in the spirit of a sustainable approach to learning? This project situates itself at the intersection of sustainable social-justice pedagogy and sonic ecoperformance, challenging the assumption that immersive media must trade ecological responsibility for sensory depth. Contribution Morphology of Kinesis tells the story of a micro-ecosystem that, through real-time AI and audience engagement, can bloom into limitless digital forests. It asks about the digitally generated feelings and possibilities of the multiplication of our experience of nature through emerging technologies. It also offers a reflection on the nature of language and how we can describe our initial imagery and expectations through a single prompt. The project draws on the bio-art lineage of Eduardo Kac (2005), who treats living matter as both medium and message. His works cover entanglements between humans and other organisms, which inspired us to rethink this ethos in the context of connecting a real terrarium with AI-driven augmentation and user interaction. We also refer to biophilic design, understood as a human inclination to seek a connection with nature and, subsequently, a translation of this need into the language of design and creative practice (Kellert, 2008). Locally, we are immersed in a discourse about sustainability and the development of green cities, minimal-energy computation and micro-scale habitats in the context of Southeast Asia. Conceptually, we are influenced by the post-naturalist philosophies of Steven Vogel, which reframe nostalgia for pristine environments as an invitation to re-imagine nature within human-shaped worlds. Significance This work demonstrates how carbon-aware interactivity can deepen ecological empathy. The project aims to engage local and international communities in searching for ways of creative expression in the spirit of a sustainable approach to learning. Observing that environmental and social issues are often interconnected, the project, behind the technical design, highlights systemic inequities tied to resource distribution and participation in decision-making processes related to spatial design.</p
Liveability scorecard for the LGA of Strathfield 2021: Understanding liveability inequities across the suburbs of Strathfield
No full textThis Local Government Area (LGA) Liveability Scorecard has been prepared by the Australian Urban Observatory in partnership with the Health Promotion Unit of the Sydney Local Health District. It has been designed to understand the liveability of individual suburbs within an LGA that can be used to prioritise future actions and investments of interest to councils, community, urban planners, developers, and other decision makers to achieve healthier and more liveable places across an entire LGA.</p
Visual Expansions in Narrating Contemporary Conflicts and History. The Possibilities of Virtual Reality (VR) Films
No full textThis article focuses on Virtual Reality films depicting contemporary conflicts, with an emphasis on building viewer-screen relations and considering the cinematographic elements establishing the emotional reaction to the films. Analyzing the visual and narrative architecture of chosen Virtual Reality productions, the author explains correlations between the level of immersion and the viewer’s experience from the perspective of film and media studies. Furthermore, the author uses multimodal critical theory as the primary methodological tool to focus on modes experienced through different sensual channels during the 360° screenings. Moreover, it is also analyzed how the discourse applied in chosen examples influences the presentation of historical events in a Virtual Reality environment. The choice of films, underlining the wide specter of thematic areas that can be covered under the term ‚contemporary conflicts,‘ allows for observing the variety of approaches.</p
Gender representation within the Victorian sport sector workforce.
No full textThere have been significant advancements to improve gender balance within the Victorian sport sector workforce, including increasing the number of women in leadership roles. However, despite these efforts and some progress in representation, women remain underrepresented across the broader workforce and in executive positions.The research used a bespoke coding script to extract data from LinkedIn profiles, which provides a comprehensive dataset of professionals that identify as having worked, or currently work, within the sport sector.The dataset included those within national and state sporting organisations, professional sporting organisations and clubs and sport and recreation facilities. Those who volunteer within community sporting clubs and associations were not included.The dataset was analysed to identify areas and trends in gender representation and churn across the Victorian sport sector workforce.The research provides a clear view of progress in the gender balance within the sector’s workforce and highlights further opportunities to improve recruitment practices, career development and retention of women.</p
<i>Sphagnum</i> Peatland Hydrological Balance Shows High Groundwater Dependence and Resilience to Short‐Term Dry Periods
No full textQuantifying the hydrological connectivity of wetland ecosystems is crucial for their sustainable management and conservation. Australian mountain peatlands typically form and persist on sloping terrain downstream of groundwater springs. This suggests that they depend heavily on groundwater inputs. The relative contributions of groundwater, surface runoff, rainfall and snow to these ecosystems have, however, not yet been quantified. This study calculated the water balance of an Australian Sphagnum peatland by continuously monitoring key hydrological parameters over 4 years (2017–2021). Precipitation (including rain and snowfall, and snowmelt), evapotranspiration, changes in peat water storage (soil moisture and water table depth), and stream outflows were monitored using an eddy covariance system with ancillary soil sensors, a piezometer array, and externally sourced precipitation data. Groundwater contributions were calculated, and baseflow separation was performed using two publicly available tools. The results showed a substantial contribution of groundwater to the ecosystem, accounting for approximately 65% of total annual inputs. Groundwater inputs sustained stream outflows of 1.5 mm per day during periods without precipitation (i.e., summer dry periods), providing persistent surface wetness in this critical growing period. A total of 94% of the peatland water balance (70% from groundwater) was lost as streamflow, thereby maintaining essential summer flows in downstream catchments. These substantial groundwater contributions may thus provide greater resilience to dry periods in hydrologically intact peatlands in Australia than previously thought.</p
Thin Metal Surface Formation
No full textContemporary robotic metal fabrication is limited by either the 2.5D conditions of surface forming or the prohibitive time and cost of additive manufacturing. This research introduces a novel sheet metal fabrication technique that integrates Incremental Sheet Forming (ISF) and Wire-Arc Additive Manufacturing (WAAM) to create complex and intricate architectural surfaces. Through a series of technical experiments and prototypes, this paper evaluates the feasibility of robotic welding and 3D metal printing on pre-formed 2.5D mild steel surfaces less than 1mm thick. It identifies key parameters in robotic 6-axis programming, CMT Cycle Step welding, and their relationship with material thicknesses. Additionally, the paper demonstrates hardware and workflow development that support this innovation. This hybrid approach aims to enhance the structural performance and complexity of thin metal surfaces while generating new design languages characterised by highly detailed patterns and distinctive material characteristics, reducing material usage and fabrication waste in architectural fabrication. The paper suggests further research into design implications for large-scale architectural applications.</p