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Deformation modelling of quasi-isotropic aerodynamic components with life cycle predictions
Get PDFThe aim of this thesis is to investigate the performance of wind turbine blades during normal operational loading cases to aid the prediction of life cycles. The main aim of this work is to critically evaluate if these devices are over-engineered to withstand extreme conditions. It is already known that these systems have a number of replacements during their whole life. The rationale for this work is to develop knowledge of the mechanical material properties used for these devices and how applying normal operating loads introduce fatigue within the materials. Using analytic theories such as Classical Lamination, bending, and Runge-Kutta techniques; along with numerical simulations via ANSYS APDL & Workbench to develop representative models and simulations to draw logical conclusions to the proposed scientific hypothesis. The key findings relating to both how wind turbine blade design, materials and behaviour responses to the loading conditions imposed. The findings will enable a deeper knowledge to the wider community, outside of engineering as well as monetary reductions unless extreme events affect the devices structure. The thesis concludes that Classical Lamination Theory can be used for orthotropic models, aerospace token test pieces can be used to determine composite material properties, layup sequencing of composites yields similar results to orthotropic equivalents, the application of twisted sections within the blade geometry increases the structural stiffness of these devices, and stress calculations can be employed irrespective of modelling software
The Effect of the Equation of State on the Properties of Disc-Instability Planets
Get PDFThe discs around young stars may be massive enough to trigger gravitational instability and fragmentation. This process may form a number of bound objects that collapse to form protoplanets. In this thesis I run hydrodynamic simulations to investigate the effect of the thermodynamics of the disc on the properties of planets that form by gravitational instability.
I model the thermodynamics of a gravitationally unstable disc with the Smoothed Particle Hydrodynamics code PHANTOM, using a barotropic equation of state (EOS) combined with a locally isothermal EOS to provide a minimum temperature floor. In doing so, I mimic the effect of radiative feedback from the central star. I explore a parameter space wherein the critical density (i.e. the density at which the EOS switches from isothermal to adiabatic), the adiabatic index and the initial disc temperature are varied. I discuss the effect of these variations on the properties of protoplanets.
Most of the fragments, regardless of the equation of state used, form second cores (i.e. protoplanets) with masses below the planetary mass threshold (13 MJ) and initial radii of 2-8R⊙. The mass of the first core increases with steeper equations of state, with the most massive fragments (> 80MJ) forming with equations of state with γ = 1.8. Broadly speaking, the fragments that form in discs governed by steeper equations of state have wider first core accretion shocks and higher specific angular momentum. Equations of state with shallow adiabatic zones (γ = 1.2) form fragments that do not reach sufficiently high temperatures in their centres to trigger the dissociation of hydrogen and so do not form a second core. These fragments fall in to one of two morphological groups: those with very small first cores with radii of ∼ 0.005 − 0.01AU and those first cores with larger radii of ∼ 0.1AU. The latter group often exhibit evidence of spirals centred on the fragment.
A key finding of this work is that though the fragments that form by gravitational instability are approximately axisymmetric, they show evidence of being flattened and are oblate spheroids rather than spherical objects as has previously been assumed. I also find that fragments accrete gas from the disc from polar-aligned inflows (along with flows on the the disc mid-plane).
I have shown that the fragments that form in gravitationally unstable discs are sensitive to the specific equation of state, with their final mass having a strong dependence on the adiabatic index. I have also found that they are not spherically symmetric and their 3D structure must not be overlooked
Drug-free in vitro activation and autologous transplantation in infertile women with diminished ovarian reserve: An experimental pilot study
Get PDFBackground: Poor ovarian response and diminished ovarian reserves (DOR) significantly contribute to female infertility. Previous attempts have been made to enhance follicular growth and improve pregnancy outcomes in these participants.
Objective: This study aimed to assess the efficacy of the in vitro drug-free activation technique of the ovarian reservation and in vitro fertilization stimulation cycle outcomes in DOR participants.
Materials and Methods: This pilot phase study investigated the impact of in vitro activation (IVA) on ovarian reservation and in vitro fertilization outcome in 10 infertile women with DOR from May to December 2023 at Taleghani Infertility Center, Tehran, Iran. Participants underwent general surgery and laparoscopy, involving the removal of a portion of one ovary, immediate transfer to the laboratory, dissection into small cubes, and subsequent re-implantation into the cases’s ovary. The primary outcomes, include the count of retrieved oocytes, the number of oocytes reaching metaphase, and the secondary outcomes were the quantity and the number of embryos transferred, implantation rate, and occurrence of clinical pregnancy.
Results: The study revealed a significant increase in the antral follicle count before and after IVA (p = 0.033). Before IVA, the median estradiol level was 93.5 (57.0), which reduced to 79.0 (35.0) after IVA, indicating a statistically significant difference. On average, 2.3 (0.8) oocytes were retrieved, among which 1.5 (0.7) were metaphase II oocytes. The observed pregnancy rate among the 2 cases was 22.2%.
Conclusion: The current study suggests that IVA may positively impact follicular growth and pregnancy outcomes among women with DOR
Prosperity gospel and social-economic challenges in Nigeria
Get PDFThe concept of prosperity gospel is the theology of all-inclusive success. It is anchored in God’s full earthly blessings. It is understood as the Christian teaching that emphasises all-round physical well-being, such as good health, financial success, prestige, personal empowerment, long life, peace, and happiness. It is the gospel that showcases itself as an all-conquering arsenal against material crises, such as unemployment, poverty, failure, diseases, barrenness, and insecurity. Often, it is sought after by people who are seeking explanation to their meaning in life amidst their social economic challenges (Phillips, 2013, Ehioghae, & Olanrewaju, 2015 & Pickering, 2013).
A link between religion and development has long been established as shown in Weber’s Protestant ethics and the spirit of capitalism. Accordingly, religious institutions are part of the central elements of a good number of civil societies. In Africa, religious activity is one of the most associative instruments for social development. In recent times, there has been the emergence of a massive wave of the prosperity gospel ideology that is sweeping across the continent. This ideology views religion and material development as intertwined. It brings with it a new mechanism for achieving material success, by radically laying claims to divine intervention with great energy and passion. The prosperity gospel views material prosperity as the birth right of every born-again Christian, and poverty as something that should be cast out.
Prosperity gospel has brought its influence to bear on Nigerian Christianity since it emerged in 19th century. It has been able to penetrate the religious space with much audacity. However, in recent years, with the advent of prosperity gospel and its compelling force amidst the increase in social-economic challenges in Africa, scholars have started to investigate the claims of the prosperity gospel phenomenon. Despite the audacious and appealing claims or teachings of prosperity gospel, the contradiction is that social-economic challenges such as poverty, sickness, unemployment, and security, which prosperity gospel seeks to address, remain a grave concern in Nigeria. Unemployment is at an alarming rate of 18.7%, poverty rate is at 42.4%, life expectancy is 53/6 years (Nigeria National Bureau of Statistics, 2017). The pressing social and public question is: Why are the fortunes of people not changing despite the proliferation of prosperity gospel in Nigerian Churches? This has generated a lot of public reactions from social media, academics, and the Christian community.
Therefore, this thesis has two focal points. First, the investigation of the responses of prosperity gospel to social-economic problems in Nigeria. This will involve responding to questions like, what are the tools deployed by practitioners of prosperity gospel in fighting bad conditions? Or simply put, how does prosperity gospel seek to address social-economic crises? Second, the thesis explores the impacts of the responses of prosperity gospel to material crises. This entails assessing the phenomenon of prosperity gospel to establish whether it has been able to achieve its aims of fighting human challenges, or whether it is just a utopian package that gives false hope to adherents amidst the prevailing social-economic upheavals.
The findings of this thesis reveal that while prosperity gospel progenitors believe that prosperity gospel propels the drive for material prosperity, the responses of prosperity gospel place more stress on divine intervention, miracles, spiritual agencies, demons, wizards, and witchcrafts. Prosperity gospel spirituality nurture a religious attention that ignore functional elements that underscore social-economic advancement. The findings suggest that prosperity gospel progenitors, appropriate religious instruments, such rhematisation, pneumatic regeneration, soteriology, prophetism, provocative giving, die by fire, prayer water, oil, and handkerchief to solve contextual battles of life. They claim that these are divine armaments capable of solving every mitigating condition of humanity. Meanwhile, the findings further reveal that while these claims are alluring, they do not practically solve bad conditions of adherents. The finding demonstrates that the content of the prosperity preaching lacks basic reality that may trigger material development. The prosperity teaching is centred on divine entities rather than the structure and system that create human suffering. Therefore, instead of motivating people to face reality, it motivates adherents to be docile as they expect a conquering entity that will miraculously stop all human woes.
The findings suggest that the response of prosperity gospel to contextual challenges in Nigeria is delusional in that it lays undue emphasis on a ‘quick fix’ rather than on substantive cause and effects. The lack of an empirical approach, where delayed gratification is instead the watch word in solving social-economic challenges, poses a grave danger to any growing society. The contents of the prosperity preaching do not highlight the need to plant, water, prune and wait for harvest. It presents life as a bed of roses where one just need to claim and grab whatever he wants. It presents a theology that relies solely on divine alteration of nature for one's benefits. To this end, the study opines that prosperity gospel claims are only a pacifying instrument that throws the adherent into a euphoria of false hope, whilst bad conditions persist. Prosperity gospel is a summon of the adherent to a panoply of momentary relief, which fades away when faced with reality of life
Importance of Bilateral Limb Symmetries in Olympic Clay Shooting: A Prospective Intervention Study
Get PDFThe presented prospective controlled trial investigated the impact of neuromuscular asymmetry correction programs on Olympic clay shooting performance. The examination involved 33 subjects over six weeks, divided into an intervention (n = 18) and a control group (n = 15). After the initial assessment, subjects in the intervention group were given personalized training protocols to correct the identified asymmetries. The analyses revealed improvements of the intervention group in grip strength asymmetry (p = 0.012), single leg balance test (p = 0.027), YBT-LQ anterior reach (p = 0.036), and composition score (p < 0.001) alongside enhanced shooting scores (p < 0.001). There were no significant changes in the control group. The findings suggest a direct link between asymmetry correction and shooting accuracy, which agrees with similar research findings of other sports. This is a novel insight into the specific fitness demands for Trap and Skeet athletes and underscores the value of addressing asymmetries and incorporating regular assessments of these parameters in training routines, along with individually tailored corrective programs
Optimization of the D2D Topology Formation Using a Novel Two-Stage Deep ML Approach for 6G Mobile Networks
Get PDFOptimizing device-to-device (D2D) topologies is pivotal for enhancing the performance and efficiency of 6G networks. This paper introduces a novel approach for forming optimal subnet trees within the 6G networks using BDIx agents and advanced Minimum-Weight Spanning Tree (MWST/MST) algorithms augmented by Graph Neural Networks (GNNs) and FeedForward Neural Networks (FFNN). Our solution aims to significantly boost network performance, particularly in high-demand scenarios such as urban areas, large-scale events, and remote locations. Our approach dynamically adapts to changing network conditions, user movements, and traffic patterns by minimizing power consumption and maximizing throughput. We implement various MWST algorithms, including Kruskal's, Prim's, and Boruvka's algorithms, and introduce a GNN model to predict edge weights combined with FFNNs to select parent nodes (called GNN-FFNN model), aiding in the construction of minimum-weight spanning trees (MWST). Additionally, a "weighted distance" metric is proposed to analyze network performance comprehensively. The proposed AI/ML-driven solution integrates BDIx agents with MWST algorithms, focusing on optimizing subnets under gNodeB in 6G networks, enhancing data transmission efficiency, reducing latency, and increasing throughput. This research contributes to developing scalable and flexible network management solutions suitable for diverse configurations and architectures
CASEE - Introducing a new assessment tool for supporting victims of Child Sexual Exploitation
No full textThis narrative review of theory introduces the basis for a new assessment tool; the CASEE (Child Adolescent Sexual Exploitation Evaluation, Ireland, Lewis & Ireland, 2023), which is then illustrated using a case study approach. The CASEE considers the vulnerability and protective factors for children and young people where concerns of child sexual exploitation (CSE) have been raised. Such concerns can include known exposure to CSE, suspected or a potential risk of exposure. The CASEE considers various vulnerability and protective factor items, developed from research involving the CASEE authors, and in response to additional research in the field. A child/young person is rated for the presenting evidence of several vulnerability factors that could present as a heightened risk of exposure to CSE, alongside protective factors that can buffer against these concerns. A key component of the CASEE is completion of an individualised formulation of understanding as to what can exacerbate vulnerabilities, alongside consideration of risk scenarios for how vulnerability can present. The aim is to understand vulnerabilities around the time of CSE concerns, and how protective factors can be maximised to safeguard the child/young person. The plans for validation of the CASEE are outlined