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Generation of Runaway Electrons (REs) during plasma disruptions is of great concern for ITER and future reactors based on the tokamak concept. Unmitigated RE generation in the current STEP (Spherical Tokamak for Energy Production) concept design is modelled using the code DREAM, with hot-tail generation found to be the dominant primary generation mechanism and avalanche multiplication of REs found to be extremely high. Varying assumptions for the prescribed thermal quench (TQ) phase (duration, final electron temperature) as well as the wall time, the plasma-wall distance, and shaping effects, all STEP full-power and full-current unmitigated disruptions generate large RE beams (from 10 MA up to full conversion). RE mitigation is first studied by modelling idealised mixed impurity injections, with ad-hoc particle transport arising from the stochasticity of the magnetic field during the TQ, but no combination of argon and deuterium quantities allows runaways to be avoided while respecting the other constraints of disruption mitigation. Initial concept of STEP disruption mitigation system is then tested with DREAM, assuming two-stage shattered pellet injections (SPI) of pure D 2 followed by Ar+ D 2 . Such a scheme is found to reduce the generation of REs by the hot-tail mechanism, but still generates a RE beam of about 13 MA. Options for further optimising the SPI scheme, for mitigating a large RE beam in STEP (benign termination scheme), as well as estimations of required RE losses during the current quench (from a potential passive RE mitigation coil) will also be discussed., QC 20240927

This study systematically explores the parameter space of disruption mitigation through shattered pellet injection in ITER with a focus on runaway electron (RE) dynamics, using the disruption modeling tool Dream. The physics fidelity is considerably increased compared to previous studies, by e.g. using realistic magnetic geometry, resistive wall configuration, thermal quench onset criteria, as well as including additional effects, such as ion transport and enhanced RE transport during the thermal quench. The work aims to provide a fairly comprehensive coverage of experimentally feasible scenarios, considering plasmas representative of both non-activated and high-performance DT operation, different thermal quench onset criteria and transport levels, a wide range of hydrogen and neon quantities injected in one or two stages, and pellets with various characteristic shard sizes. Using a staggered injection scheme, with a pure hydrogen injection preceding a mixed hydrogen-neon injection, we find injection parameters leading to acceptable RE currents in all investigated discharges without activated runaway sources. Dividing the injection into two stages is found to significantly enhance the assimilation and minimize RE generation due to the hot-tail mechanism. However, while a staggered injection outperforms a single stage injection also in cases with radioactive RE sources, no cases with acceptable RE currents are found for a DT-plasma with a 15MA plasma current., QC 20240723

INTRODUCTION: Adolescence is a period of major transition in physical, cognitive, social and emotional development, and the peak time for the onset of mental health conditions, substance use disorders and sexual and reproductive health risks. Prevention and treatment during this time can improve health and well-being now and into the future. However, despite clinical guidelines recommending annual preventive health assessments for young people, health professionals cite lack of consultation time and adequate funding as key barriers. This trial aims to determine whether a specific fee-for-service ('rebate payment') for a young person's health assessment, is effective and cost-effective at increasing the detection and management of health risk behaviours and conditions among young people. METHODS AND ANALYSIS: This cluster randomised controlled trial will be conducted in Australian general practice. 42 general practices (clusters) will be randomly allocated 1:1 to either an intervention arm where general practitioners receive a rebate payment for each annual health assessment undertaken for 14-24-year-olds during a 2 year study period, or a control arm (no rebate). The rebate amount will be based on the Medical Benefits Schedule (Australia's list of health professional services subsidised by the Australian Government) currently available for similar age-based assessments. Our primary outcome will be the annual rate of risk behaviours and health conditions recorded in the patient electronic health record (eg, alcohol/drug use, sexual activity and mental health issues). Secondary outcomes include the annual rate of patient management activities related to health risks and conditions identified (eg, contraception prescribed, sexually transmitted infection tests ordered). A process evaluation will assess acceptability, adoption, fidelity and sustainability of the rebate; an economic evaluation will assess its cost-effectiveness. Analyses will be intention-to-treat. ETHICS

Rising levels of Environmental Air Pollution (EAP) caused by wildfires and traffic emissions impact Indoor Air Quality (IAQ) by penetrating buildings through air conditioning intakes and door and window openings. Exposure to fine Particulate Matter (PM2.5) causes building occupant discomfort and significant health issues. Hence, it is vital to continuously monitor the PM2.5 exposure level and the general IAQ of buildings. This study uses Internet of Things (IoT) sensors to investigate the temporal and spatial correlations between indoor and outdoor PM2.5 concentrations in a university building in Sydney, Australia, over five months. Sensor measurements are used to determine the Indoor to Outdoor (I/O) ratio and Exceedance Index (E-index). The study timeline included impacts associated with Hazard Reduction Burning (HRB) and localized peak traffic flow. The findings reveal that the closest indoor area to the building entrance exceeded double the World Health Organization (WHO) PM2.5 recommended threshold for more than 80% of the study period. Results also confirm a negative correlation between the distance from ground level and indoor PM2.5 exposure. An hourly analysis shows that the PM2.5 concentrations in Winter increase overnight. During HRB in Winter, the I/O ratios increased by up to 200% on average during regular HVAC operating hours. Localized outdoor readings were also compared with the nearest regional air quality monitoring station (RAQMS). Those results indicate that the average PM2.5 for the local outdoor sensor was approximately 2.5 times higher than the nearest RAQMS, confirming that regional stations may not be reliable references for localized PM2.5 concentrations.

Purpose: To achieve the building and property by 2050, decarbonisation goals will now require a significant increase in the rate of improvement in the energy performance of buildings. Occupant behaviour is crucial. This study seeks to guide the application of smart building technology in existing building stock to support improved building energy performance and occupant comfort. Design/methodology/approach: This study follows a logical partitioning approach to the development of a schema for building energy performance and occupant comfort. A review of the literature is presented to identify the characteristics that label and structure the problem elements. A smart building technology framework is overlaid on the schema. The framework is then applied to configure and demonstrate an actual technology implementation for existing building stock. Findings: The developed schema represents the key components and relationships of building energy performance when combined with occupant comfort. This schema provides a basis for the definition of a smart building technologies framework for existing building stock. The study demonstrates a viable configuration of available smart building technologies that couple building energy performance with occupant comfort in the existing building stock. Technical limitations (such as relatively simple building management control regimes) and pragmatic limitations (such as change management issues) are noted for consideration. Originality/value: This is the first development of a schema to represent how building energy performance can be coupled with occupant comfort in existing building stock using smart building technologies. The demonstration study applies one of many possible technology configurations currently available, and promotes the use of open source applications with push-pull functionality. The schema provides a common basis and guide for future studies.

Australia’s building energy use accounts for a significant portion of the country’s energy consumption and greenhouse gas emissions. Buildings consume energy for a variety of purposes, including space heating, cooling, lighting, and powering electronics. Smart and sustainable building management practices allow buildings to be managed and operated more efficiently and sustainably. This study investigated the energy consumption and building management performance of a university building in Sydney, Australia. The experiment was performed by monitoring occupant comfort and building performance feedback with a push-pull mobile phone application and portable sensor technologies. The results showed that several factors influenced the occupants’ environmental comfort level, including temperature, lighting, noise, air quality, air movement, and relative humidity. Nevertheless, the ambient office temperature has a significantly higher impact on occupants’ comfort level. Results also showed that the local temperature experienced and preferred by individual occupants may vary, even under identical thermal conditions. The outcomes also confirmed strong correlations between the comfort and concentration levels (r(231) = 0.61, p = 0) and between the comfort and productivity levels (r(231) = 0.62, p = 0). Temporal analysis also revealed lower comfort levels between 13h00 and 16h00 and higher comfort levels between 10h00 and 12h00 and 17h00 and 19h00. The findings of this research indicated that ≤4% of total annual building energy consumption costs may be saved by more effectively and efficiently managing office thermostat control. More accurate and zone-based energy analysis could also reveal higher energy savings through smart occupant feedback-oriented thermostat and lighting control in commercial and office buildings.

Purpose: The purpose of this study is to highlight and demonstrate how the study of stress and related responses in construction can best be measured and benchmarked effectively. Design/methodology/approach: A range of perceptual and physiological measures are obtained across different time periods and during different activities in a fieldwork setting. Differences in the empirical results are analysed and implications for future studies of stress discussed. Findings: The results of this study strongly support the use of multiple psychometrics and biosensors whenever biometrics are included in the study of stress. Perceptual, physiological and environmental factors are all shown to act in concert to impact stress. Strong conclusions on the potential drivers of stress should then only be considered when consistent results apply across multiple metrics, time periods and activities. Research limitations/implications: Stress is an incredibly complex condition. This study demonstrates why many current applications of biosensors to study stress in construction are not up to the task and provides empirical evidence on how future studies can be significantly improved. Originality/value: To the best of the author’s knowledge, this is the first study to focus explicitly on demonstrating the need for multiple research instruments and settings when studying stress or related conditions in construction.

Transport processes around the magnetic X-point of tokamaks, such as turbulence and mean-field drifts, are scarcely understood. The assessment of the capability of turbulence codes to quantitatively reproduce these dynamics has been hampered by limitations in computational power and available experimental data. In this paper, we present a rigorous validation of full-scale simulations of a newly developed X-point scenario in the basic toroidal plasma device TORPEX, performed with the four state-of-the-art codes FELTOR, GBS, GRILLIX, and STORM. High-resolution Langmuir probe array measurements of various time-averaged and fluctuating quantities and across the entire cross section of TORPEX show that this X-point scenario features the key ingredients of X-point dynamics, such as small-scale fluctuations and background drifts. The codes are able to qualitatively reproduce some characteristics of the time-averaged fields, such as the ion saturation current profiles at mid-height, the plasma up-down asymmetry, and the blob trajectories. A quantitative agreement is found for the background E × B velocity pattern, while the fluctuation levels are generally underestimated typically by factors of 2 or more, and thus, background fluxes are found to dominate over turbulent ones in simulations. The sensitivity of the simulation results on the plasma collisionality and on the position of the sources is tested in GBS, showing a mild effect on the overall quantitative agreement with the experiment. Overall, this validation reveals the challenges to reproduce the plasma dynamics near an X-point and provides a clear path to a quantitative and computationally relatively inexpensive assessment of future developments in turbulence codes.

Notwithstanding the neuromyth controversy, the malleability of learning style preferences impacts the validity of the measurement instrument and the effectiveness of the associated model of learning. This study investigates the test–retest reliability and underlying dynamics of Kolb’s Learning Style Inventory (KLSI). It surveys 245 college-level students in Australia, over three rounds of data collection at 7-week intervals. Results show that over 75% of participants are incorrectly categorised, and more than 50% materially changed their category of learning style between rounds. The study reveals that individuals roam freely, rapidly, and extensively across learning style categories. Thus, the categorical differences measured by the KLSI lack meaningful purpose. Whether or not learning styles are a neuromyth, this study indicates that the act of learning, as an act of agency, is fluid with potentiality and choice. The more meaningful focus for teaching and learning practice would then be on student commonalities, not categorical difference.