47011 research outputs found
Sort by
Impact of internal power factor angle on thermal response of stator winding insulation in synchronous generators
No full textThe power factor in electric power systems change frequently due to increases in load demand. Consequently, the internal power factor angle (IPFA) of synchronous generators vary under different operating conditions. Accurately understanding the performance of synchronous generators under various IPFAs is of great significance for ensuring the stable and efficient operation of power systems. This paper presents the first investigation of the thermal responses of the stator winding insulation in synchronous generators under different IPFAs. The impacts of the IPFA on the magnetic flux density (MFD), stator current, and losses are comprehensively studied. Unlike other research, this article takes into account the interactions between core—loss—induced heat and copper—loss—induced heat. In addition, it delves into the impact of the IPFA on thermal degradation distribution patterns. Based on the electromagnetic—thermal—structure coupling calculation, the critical points in winding insulation are identified by the distribution of thermal responses under varied IPFAs. Finally, experiments are conducted on a 5 kW prototype generator to verify the accuracy of theoretical analysis and FEA calculation
Urban mapping in Dar es Salaam using Angle-Based Joint and Individual Variation Explained
Full text linkMapping deprivation in urban areas is important, for example, for identifying areas of greatest need and planning interventions. Traditional ways of obtaining deprivation estimates are based on either census or household survey data, which in many areas is unavailable or difficult to collect. However, there has been a huge rise in the amount of new, nontraditional forms of data, such as satellite imagery and cell-phone call-record data, which may contain information useful for identifying deprivation. We use Angle-Based Joint and Individual Variation Explained (AJIVE) to jointly model satellite imagery data, cell-phone data, and survey data for the city of Dar es Salaam, Tanzania. We first identify interpretable low-dimensional structure from the imagery and cell-phone data, and find that we can use these to identify deprivation. We then consider what is gained from further incorporating the more traditional and costly survey data. We also introduce a scalar measure of deprivation as a response variable to be predicted, and consider various approaches to multiview regression, including using AJIVE scores as predictors
Failure and Reliability Analysis of PEM Electrolyser Balance of Plant
No full textRenewable energy technologies, such as polymer electrolyte membrane electrolysers (PEME), have garnered significant attention due to their high efficiency and potential for reducing emissions in the industrial, transportation and energy sectors. To ensure reliable and efficient operation of PEME plants, a comprehensive understanding of operation of Balance of Plant (BoP) components, their failure modes, and associated maintenance procedures is required. This study presents a foundational insight for optimising the operation and maintenance of PEME BoP systems, by conducting a detailed reliability analysis of the water subsystem using Failure Mode and Effect Analysis (FMEA) and Fault Tree Analysis (FTA). Thirty (30) component failure modes, their effects, and mitigation strategies, are identified. Fault trees are developed to illustrate the causes of two critical undesirable events: water quality degradation and water supply interruption, with calculated system unavailability probabilities of 0.49 and 0.68, respectively. The analyses highlight the influence of component failure modes on the overall system availability and identifies the most critical components through minimal cut set analysis. Importance measures are used to quantify each component's contribution to the overall system unavailability and failure frequency. These findings can inform effective operational and maintenance decisions, thereby improving the availability and reliability of PEME plants
‘It’s like sunk cost fallacy or something they call it’: The role of symbolic, social and economic capital in worker motivations for staying in the UK television production sector
Full text linkThis paper seeks to explain why workers stay within the UK TV production sector, despite its well-documented problems. By drawing together literature around Bourdieu’s forms of capital with the concept of sunk costs, the paper argues that sunk cost fallacy (i.e. the time, effort and investments already incurred by the individual worker) is a central motivation for professionals retaining their place within the industry. It is particularly the notion of the sunk cost fallacy, in relation to their previous investments of cultural, social and symbolic capital, which drives TV workers to stay. The paper explores this notion of sunk costs through in-depth interviews conducted with 30 workers involved in TV production in the UK conducted from March 2024 to December 2024, as part of the AHRC-funded ReCARE TV Project (grant number AH/X00676X/1). The findings suggest a new conceptual framework through which to understand worker motivation in the creative industries, at a moment when the relationship between labour and capital is being redefined
Strain-induced optical degradation on thermal performance of radiative cooling-coated PVC membrane
Full text linkRadiative cooling-coated polyvinyl chloride (PVC) membranes offer an effective solution to reduce cooling energy demand in membrane-based buildings. However, PVC membranes as load-bearing components are subjected to significant tensile deformation, which may alter the microstructure of the coating and degrade its spectral selectivity and cooling capacity. In this study, a radiative cooling coating was developed and applied to PVC membranes, and its optical stability and cooling performances under varying uniaxial strains were systematically investigated through macro-scale measurements and micro-structural analysis. It is obtained that uniformly dispersed BaSO4 microparticles enhance Mie scattering, enabling a solar reflectance of 92.4% across 0.3–2.5 μm. Vibrations of abundant functional groups contribute to a high mid-infrared emissivity of 93.1% in the 8–13 μm atmospheric window. With increasing strain, surface roughening and crack formation disrupt scattering paths, resulting in a reflectance reduction to 87.5%, while the chemical structure remains stable and emissivity only slightly decreases to 92.0%. Outdoor tests confirm that unstrained membrane achieves a peak temperature reduction of 7.1 °C due to the synergy of high reflectance and high emissivity. Tensile strain weakens Mie scattering and reduces cooling efficiency, but the coated membrane still achieves a 6.3 °C temperature drop. This study reveals the strain-dependent optical and thermal mechanisms of radiative cooling coatings in their application to membrane materials, and provides technical and theoretical support for the performance evaluation and practical deployment of radiative cooling-coated membrane structures
Scoping Reviews in Health Professions Education
Full text linkScoping reviews are becoming increasingly popular in Health Professions Education (HPE), offering a flexible and systematic way to explore broad questions, map the literature, and identify knowledge gaps. Unlike systematic reviews, which aim to answer focused questions, scoping reviews are ideal for topics that are complex, emerging or poorly defined. They allow educators to explore what is known about a topic, highlight areas needing further research and inform curriculum design, policy or funding decisions. This Clinical Teacher's Toolbox article introduces the purpose and defining features of scoping reviews and compares them with other common review types. We offer practical advice based on our experience of conducting scoping reviews in HPE, with step-by-step guidance on how to plan, conduct and report. Topics include choosing a suitable research question, assembling a team (including the key role of librarians), managing the review process using software tools and following established methodological frameworks (e.g., the Joanna Briggs Institute). Common challenges, such as justifying the use of scoping reviews and ensuring quality, are discussed, along with tools like the PRISMA-ScR checklist to enhance transparency. By following this guide, all involved in HPE can confidently use scoping reviews as a rigorous and adaptable method of evidence synthesis, supporting both educational research and informed decision-making for best educational practices
Designing immersive experiences for heritage sites: Developing VR-focused guidance based on a case study of Nottingham's caves
Full text linkImmersive technologies such as Virtual and Augmented Reality (VR and AR) are increasingly being adopted by cultural institutions to enhance engagement, learning and emotional connection. However, questions remain around inclusivity, sustainability, and authenticity. This paper reports a qualitative case study of Nottingham's historic caves, in which prototype VR and AR demonstrators were used as discussion prompts with technology developers, heritage stakeholders, and public visitors. Semi-structured interviews (n = 32) explored perceptions of immersion, accessibility, feasibility, educational value, and ethics. Findings show that immersive experiences can deepen emotional connection and foster curiosity, but their impact depends on delivery context, usability, and institutional support. Participants highlighted risks of exclusion, technical fragility, and narrative ambiguity, alongside opportunities for widening access and enhancing learning. The study contributes practical guidance for designing inclusive, authentic, and sustainable immersive heritage experiences, emphasising co-design, hybrid delivery models, and transparent operational planning
Bureaucratised Risk: Ethical and Moral Blindness in Contemporary Penal Practice
Full text linkThis paper explores how risk bureaucracies that have come to dominate in contemporary penal practice can result in diverse forms of Ethical and Moral Blindness. These issues arise when the deployment of penal institutional aims related to risk, and administrative risk technologies, results in practices that are either blind to the impacts for individuals in prison (ethical) or in blindness to the very humans central to that risk work (moral). Here I explore three forms of risk practice that are foremost in the contemporary prisons of England and Wales to think through the implications of these issues for broader penal policy: 1. Forensic Psychology; 2. Prison Security; 3. the National Research Committee that oversees applications by external parties to conduct research in prisons. I will argue that for each of these bureaucratised risk processes there are resulting harmful, unethical, and immoral practices that arise out of institutional and system level risk obsessions
Respecting nature’s limits in urban planning: values and principles for human–nature partnerships
Full text linkThe transgression of planetary boundaries demands that societal and ethical limits to Nature’s availability for human use, impact, and consumption are set, particularly in cities. However, so far, we lack an understanding of how sustainability-aligned values can define such limits and how limits can be operationalized in practice. The objectives of this perspective paper are therefore twofold. First, based on partnership ethics and the sociological concept of Uncontrollability, we identify broad values that feed into the concept of human-nature partnerships that respect limits to making Nature controllable. Second, we translate these broad values into four guiding principles that support urban planning to operationalize human-nature partnerships. Planning for urban human-nature partnerships thereby enables cities to become regenerative, healthy, convivial, and compassionate. Our concept of urban human-nature partnerships provides a heuristic for amplifying Nature’s voice and underscores the importance of relational capacities that enable urban planning to respond attentively
Diverse hydrogen chemistry with perspectives for energy storage
Full text linkThe chemistry of hydrogen and its interaction with matter is remarkably diverse with new discoveries and materials continuously being uncovered. New types of chemical bonding and interactions allow for the preparation of new compounds with unusual compositions and properties. For instance, neutral hydrogen molecules may spontaneously form penta-dihydrogen clusters, (H2)5, in nanoporous materials with extremely dense packing, similar to metallic hydrogen at high pressure. Hydrides with extreme hydrogen densities – ‘superhydrides’ – have yielded record critical temperatures under pressure and now guide routes toward low-pressure high-temperature hydride superconductors. A well-known weak interaction identified in biological matter, the hydrogen bond, has an inorganic analogue: the dihydrogen bond. These two interactions have very similar bond lengths and bond strengths that are known to produce flexible and relatively open structures, which often have interesting functionalities. Recently, the di-hydrogen bond has come into focus for development of fast divalent magnesium and calcium cationic conductors. In this review, we highlight key advances in the synthesis and characterisation of novel hydrogen-based materials and illustrate how the compositional and structural versatility of hydrides leads to new functionalities. Hydrides are highly relevant materials with a diversity of energy applications such as solid-state hydrogen storage, solid-state batteries and superconductors, as well as future global hydrogen transportation
Access Repository Dashboard
Do you manage Open Research Online? Become a CORE Member to access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard! 👇