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Optimizing demand-side energy management for stand-alone wind-solar microgrids in rural settlements: A case study for nomadic Yurt in Kazakhstan
Full text linkNomadic communities often reside in remote regions requiring extensive transmission infrastructure, which is costly and contributes to higher greenhouse gas emissions. This study proposes a hybrid microgrid (MG) for the Shell Yurt Center, a representative nomadic dwelling in Kazakhstan. The system integrates renewable energy sources (RESs), including photovoltaic (PV), wind turbine (WT), and battery energy storage systems (BESS), to deliver a reliable and cost-effective energy supply. An analysis of a home energy management system (HEMS) is conducted using real-time data of the Yurt to support efficient demand-side management (DSM). The HEMS is designed to enhance energy efficiency and reduce overall energy costs through the smart scheduling of household appliances. Dynamic Programming (DP) and Genetic Algorithm (GA) are applied to manage energy usage under an unscheduled electricity pricing rate of 42,028), LCOE (466/year). Overall, the study establishes an optimal scheduling framework for renewable energy (RE) utilization for nomadic dwellers using a fully functioning MG complex
Residual Cardiovascular Biomarkers After Medical Therapy and Their Prognostic Implications Following Percutaneous Coronary Intervention
Full text linkBackground Despite medical therapy, atherothrombotic events remain common in high-risk patients with coronary artery disease. Objectives The purpose of this study was to evaluate the association between atherothrombotic biomarkers and outcomes in patients with coronary artery disease who are undergoing percutaneous coronary intervention (PCI). Methods Biomarkers including lipid profile (low-density lipoprotein cholesterol and triglycerides), inflammation (high-sensitivity C-reactive protein [hs-CRP]), platelet reactivity (P2Y12 reaction unit), and coagulation (fibrinogen) were measured on admission and at 1 month following medical therapy post-PCI (n = 2,789). The primary endpoint was major adverse cardiovascular events, defined as a composite of cardiovascular death, myocardial infarction, or stroke, occurring between 1 month and 4 years post-PCI. Results Biomarker levels decreased significantly (all P values ≤ 0.001), except for fibrinogen levels (329 ± 86 vs 359 ± 92 mg/dL; P < 0.001). The median follow-up of the participants was 2.2 years (IQR: 1.3–4.0 years). Covariate-adjusted HRs for the lowest to highest quartiles were 1.00 (referent) (95% CI), 1.37 (0.78-2.41), 1.89 (1.11-3.21), and 1.71 (1.01-2.91) for 1-month hs-CRP; and 1.00 (referent), 1.49 (0.83-2.67), 1.83 (1.03-3.26), and 2.47 (1.40-4.36) for 1-month fibrinogen. Among these biomarkers, hs-CRP and fibrinogen levels at 1 month showed the highest correlation (r = 0.426). After adjusting for covariates and biomarkers, the 1-month fibrinogen level was the strongest incremental predictor of major adverse cardiovascular event (HRs: 1.00 [referent], 1.45 [0.80-2.62], 1.65 [0.91-2.98], and 2.23 [1.20-4.12], P < 0.001). Conclusions Among medically treated patients following PCI, elevated fibrinogen levels were associated with adverse outcomes. Further studies are warranted to clarify these associations and to determine whether adjunctive therapies can improve outcomes in this high-risk group. (Gyeongsang National University Hospital [GNUH] Registry; NCT04650529
A discrete memristive heterogeneous Hopfield neural network with multi-penguin-like/silkworm-like attractors and its application in secure communication
No full textThe activation function is one of the extremely crucial components of an artificial neural network. It not only provides the neural network with nonlinear capability, but also enhances its expressive power. However, discrete neural networks with multi-attractors consisting of different activation functions have not yet been uncovered. In this work, a discrete memristive Hopfield neural network with heterogeneous activation functions and multi-penguin-like/silkworm-like attractors is proposed. The discrete memristor is used as a synapse to mimic activity between neurons with heterogeneous activation functions. Theoretical analysis and numerical simulation reveal that the system can generate various multi-penguin-like/silkworm-like attractors, and exhibit complex dynamical behaviors, including transient chaos, attractor evolution, homogeneous and heterogeneous coexisting attractors, and initial offset behavior. Meanwhile, bi-parameter dynamic results demonstrate the proposed system’s hyperchaotic and high spectral entropy properties. Furthermore, a hardware platform is designed to verify the validity and feasibility of the proposed system by adopting FPGA. Finally, the randomness of the system-generated sequences is assessed, and a secure communication scheme is presented based on the discrete memristive heterogeneous Hopfield neural network. The experimental results indicate that the proposed model performs better than existing chaotic maps
The Practice of Authority in Academic leadership/Management
Full text linkThis study sought to advance understanding of authority in higher education academic management/leadership. Although there is rich literature on education management and leadership, the role of authority in this area has received less attention. Drawing on an understanding of authority as social, multiple, changeable and contested, this study had three broad aims: to understand contextualised authority practices; to conceptualise authority in academic leadership/management and to investigate the value of practice-focused constructivist grounded theory methodology in educational research. Data were collected from the Education Departments of two, post 1992, UK universities over a period of eighteen months and analysed using elements of practices as a sensitising framework. The study shows how elements combine in construction of authority. Three practices: overseeing, deciding and challenging, are considered. The study contributes to the discussion on academic leadership and management. Findings demonstrate the complexity of authority practices in this domain. Four ideas in particular stand out: that access to knowledge and material resources confers or restricts authority; that elements and everyday practices combine to create a ‘toolkit’ from which authority practices can be constructed; that grouping multiple authorities into a triad of structuring, relational and knowledge-based authorities can cast light on constructions and contestations of authority; and that knowledge-based authorities in higher education have multiple and conflicting sources that draw on different higher education discourses. Finally, the study suggests the value of practice focused grounded theory methodology in shifting focus from an agentic understanding of academic leadership/management
Decolonising water resource allocations: towards a typology of experiences in small island developing states
Full text linkThis paper explores the role of colonial legacies on contemporary water resource allocations in Small Island Developing States (SIDS) and current experiences with decolonisation processes. Drawing on three case studies − Mauritius, Papua New Guinea, and Cabo Verde − the article provides a typology of SIDS’ experiences in decolonising their water resources – maintenance of the status quo, de jure but no de facto change, and de facto change. The paper argues that differences in decolonisation outcomes can be partly explained by the existence of Indigenous populations prior to colonisation, as well as the relative abundance of water resources. The findings highlight the context-specific nature of decolonising water resources and caution against one-size-fits-all approaches pushed by international institutions. The paper calls for further research on how global financial and aid agencies influence water governance in postcolonial SIDS contexts, where fiscal constraints and dependence on external actors pose additional challenges to equitable water allocations
Review of trajectory planning methods for civil supersonic aircraft
No full textRenewed interest in supersonic air travel has prompted researchers to reconsider the design and operation of supersonic transport aircraft. Previously, such aircraft were restricted to overwater routes due to the disturbances caused by their sonic booms. Now, however, low-boom designs and overland flight at marginally supersonic Mach numbers are seen as potential enablers for widespread supersonic air travel. As a result, the trajectories that next-generation supersonic transports may fly are likely to be less constrained than for previous types, and in the last decade there has been a noticeable increase in research focusing on trajectory planning for such aircraft. This paper reviews the different methods that have been used to generate and optimise the flight paths of past and future supersonic transports. The challenges associated with optimising trajectories for aircraft that do not yet exist are discussed, and suggestions for future research activity are presented. Climate-optimal trajectory planning and development of detailed, non-proprietary supersonic aircraft performance models are identified as two key areas for future work
Effects of transcranial direct current stimulation (tDCS) at different cortical targets on cognition in obsessive compulsive disorder (OCD): an exploratory analysis
Full text linkTranscranial direct current stimulation (tDCS) holds promise as a treatment for obsessive-compulsive disorder (OCD). Patients with OCD show impairment in specific domains of cognitive flexibility and response inhibition. We previously reported that tDCS produced a positive clinical effect on OCD symptoms. Here, we report a secondary analysis of neurocognitive data. In this randomized, double-blind, sham-controlled, crossover, multicenter feasibility study, adults with a diagnosis of OCD according to the diagnostic and statistical manual of mental disorders, fifth edition (DSM-5) received three courses of clinic-based tDCS, targeting the left orbitofrontal cortex (L-OFC), bilateral supplementary motor area (SMA), and sham, randomly allocated and delivered in counterbalanced order. Cognitive assessments were conducted before and 2-h after the first stimulation in each arm. Nineteen adults were recruited. tDCS of both the L-OFC and SMA significantly improved cognitive inflexibility, while sham treatment did not (paired-sample t test, baseline vs. 2-h after stimulation). No significant effect of tDCS was found for motor impulsivity (stop-signal reaction time) in any of the three arms. In a small sample of patients with OCD, a single administration of tDCS to the L-OFC and SMA produced a rapid improvement in cognitive inflexibility but not in motor impulsivity. A definitive randomized, controlled trial of tDCS targeting both the OFC and SMA, including cognitive markers, is indicated
Perceptions of cultural competency in antenatal care amongst midwives and Nigerian mothers in the UK- A qualitative descriptive study
No full textBackground: Recently migrated Black African women in the United Kingdom have an increased maternal mortality rate linked to reduced or non-engagement with routine antenatal care. Cultural factors are suggested to impact on utilisation of antenatal care. Aim: To explore the perceptions of cultural competency during routine antenatal care amongst midwives and recently migrated Nigerian mothers in the UK and identify the cultural factors that are valued by midwives and mothers. Methods: A generic qualitative approach involving two focus groups with eight midwives and 15 one-to-one interviews with mothers was undertaken between March 2023 and May 2024. Conventional content analysis was used to analyse the data. Setting: The setting was two NHS Trusts in London, which were in the top ten boroughs for births to African mothers. The mothers were recent migrants to the UK ( less than five years), had received routine antenatal care in the UK and had delivered a live baby in the last year. Midwives who had current or previous experience of providing routine antenatal care were invited to participate. Findings: The findings show that midwives are aware of the importance of cultural competency during routine antenatal care provision. Four themes emerged from the focus groups’ discussions: (1) antenatal care in the midst of cultural ambiguity, (2) lack of space for cultural understanding, (3) preserving culture and individuality and (4) cultural hesitancy and impediments. The one-to-one interviews with Nigerian mothers revealed a complex picture of their antenatal care experiences consisting of eight themes: (1) overlooking of culture during pregnancy care, (2) sharing but not exposing culture, (3) cultural expectations of antenatal care, (4) navigating pregnancy within two cultures, (5) cultural opinions on information needs, (6) essence of care versus cultural knowing and skill, (7) culturally embraced communication and interactions and (8) respectfulness across cultures. Conclusion: This study reveals that migrant Nigerian women are not routinely asked about their culture during antenatal care provision and either choose to hide or reveal their culture, therefore exploration of their cultural values and needs are dependent on midwives’ cultural competence. Mothers valued their culture however, traversing pregnancy in a new country was prioritised over their cultural needs. This study also highlights that midwives’ ability to demonstrate cultural competency during antenatal care provision is impacted by societal, personal, professional, and organisational factors. These findings emphasis the importance of midwives having a focused discussion of a woman’s culture to integrate any cultural preferences into antenatal care provision and a requirement for organisational policy and professional guidance to focus on the culture of the woman
Sensor Driven Resource Optimization Framework for Intelligent Fog Enabled IoHT Systems
Full text linkFog computing has revolutionized the world by providing its services close to the user premises, which results in reducing the communication latency for many real-time applications. This communication latency has been a major constraint in cloud computing and ultimately causes user dissatisfaction due to slow response time. Many real-time applications like smart transportation, smart healthcare systems, smart cities, smart farming, video surveillance, and virtual and augmented reality are delay-sensitive real-time applications and require quick response times. The response delay in certain critical healthcare applications might cause serious loss to health patients. Therefore, by leveraging fog computing, a substantial portion of healthcare-related computational tasks can be offloaded to nearby fog nodes. This localized processing significantly reduces latency and enhances system availability, making it particularly advantageous for time-sensitive and mission-critical healthcare applications. Due to close proximity to end users, fog computing is considered to be the most suitable computing platform for real-time applications. However, fog devices are resource constrained and require proper resource management techniques for efficient resource utilization. This study presents an optimized resource allocation and scheduling framework for delay-sensitive healthcare applications using a Modified Particle Swarm Optimization (MPSO) algorithm. Using the iFogSim toolkit, the proposed technique was evaluated for many extensive simulations to obtain the desired results in terms of system response time, cost of execution and execution time. Experimental results demonstrate that the MPSO-based method reduces makespan by up to 8% and execution cost by up to 3% compared to existing metaheuristic algorithms, highlighting its effectiveness in enhancing overall fog computing performance for healthcare systems
A Modal-based Contribution to Damage Location in Laminated Composite Plates
Full text linkThe need for damage detection on complex structures at an early stage, has led to the development of techniques that evaluate changes on vibration parameters, since the dynamic response of a structure is dependent on its particular characteristics. The generality of the vibration based damage detection techniques are based on the fact that damage will induce a local reduction on the component stiffness. However, no single approach has proven appropriate for all situations. Composite materials, which are receiving an increasing attention in the aeronautical and other industries, namely Carbon Fibre Reinforced Polymers (CFRPs), are very sensitive to impacts of medium and low energy. Typically, Barely Visible Impact Damage (BVID) will occur, constituting an unsafe failure of difficult assessment. To assess (detect, locate and quantify) damage in this kind of material is still a challenge, especially if a huge amount of sensors or expensive equipments are not available. In this work, a methodology that makes use of a reduced amount of conventional sensors is explored, with the aim of locating damage on laminated components that are subjected to impacts during service for a low cost. This represents a considerable benefit, namely for the assessment of damage in aeronautical components, when compared to most methods used today. This work can also give a major contribution to the research community since uncommon approaches will be used to model damage in composite materials, namely the modal damping factor as feature for damage location