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Effects of a breakwater on a floating solar farm in heading and oblique waves
Get PDFFloating photovoltaic (FPV) solar farms have gained significant research and industrial interest in recent years. However, to support its deployment in abundant ocean space, FPV is required to be protected against wave loading. Thus, the usage of a breakwater in front of a floating solar farm is particularly promising. In this work, a time-domain simulation model for an array of FPV solar units in heading and oblique waves was established. Following validation against experiments, the model was used to predict the wave-induced motion and loading responses of each floating solar unit in an array, first without a breakwater, and subsequently with a breakwater. By comparison, it was found that a breakwater can reduce the wave-induced motions of a floating solar farm by up to 56%, alongside up to 55% reduction of loading on the joints between FPV units. However, the breakwater is less effective in relatively long waves and could induce some increase in loading on joints, signifying future work to optimize the design of the breakwater based on the intended environmental condition. Overall, the present results provide insights into a practical breakwater solution for FPV in offshore and coastal conditions, supporting the long-term development of this industry.L.H. acknowledges grants received from Innovate UK (Grant Nos. 10048187, 10079774, and 10081314), the Royal Society (Grant Nos. IEC∖NSFC∖223253 and RG∖R2∖232462), and UK Department for Transport (TRIG2023—Grant No. 30066).Physics of Fluid
The comprehensive review of vision-based grasp estimation and challenges
Get PDFRobotic grasping has emerged as a fundamental skill and a vital task for a robotic manipulator in various sectors over recent decades. Although a preprogramming method is now a general application, the challenges to handling complicated and unstructured scenarios remain. Machine vision, therefore, has become a focus of interest from many researchers as a primary perception to provide flexible manipulation in unknown and uncertain environments rather than control working space. This research presents a comprehensive review of vision-based grasp detection for a parallel gripper, analyzing potential techniques, existing challenges, and future directions. It delves into fundamental concepts of grasp detection and estimation, including traditional and learning-based methods. Additionally, the study explores essential benchmark datasets and metrics. This paper not only offers opportunities to develop grasp detection methodologies but also applications in the real world, such as fruit picking in agriculture, pick-and-pack items in supermarkets and logistics, and pick-and-sort objects in manufacturing. This will enable substantial changes and impacts of the robotic manipulator in the modern world.2024 29th International Conference on Automation and Computing (ICAC
A preliminary economic analysis of the process of decarbonising an oil-exporting country: the case of Libya
Get PDFThis paper offers a basic analysis for strategic decision-makers of the process when an economy shifts from oil to non-carbon energy exports and zero carbon emissions. The fundamental concept is how to offer environmental performance without causing an economic contraction. The costs and feasibility of solar, wind, and helium closed-cycle technologies are thoroughly and independently compared. Solar panels make up 0.67% of the USD 1.14 trillion total cost of solar energy, which is the capital investment, with panels accounting for 0.51%. Future technical developments are expected to bring down the cost of such solar farms to USD 0.74 trillion. Turbines comprise 66% of the estimated USD 0.67 trillion wind energy costs. At USD 0.36 trillion, helium closed-cycle gas turbines—which account for 0.78% of the overall cost—are essential for stabilising energy output. With a focus on cost viability, this analysis offers direction for Libya’s transition to energy self-sufficiency and export, in support of global carbon reduction targets. It also offers unique insights into areas not previously covered by other studies. This paper’s unique contribution is its economic analysis of the decarbonisation of an entire oil-exporting nation.Win
Enhancing fault characterisation in composites using infrared thermography: a bee colony optimisation approach with self-organising maps
Get PDFThis work presents an innovative approach aimed at enhancing the characterisation of discontinuities through the processing of thermographic images. The proposed methodology combines self-organising maps (SOM) with bio-inspired parameter optimisation through bee colony optimisation technique. The primary focus is on improving the quality of the fault quantification metric known as the signal-to-noise ratio (SNR). The goal is to achieve a better fault visualisation, ultimately contributing to the advance of thermography as a non-destructive technique. To validate this novel approach, an experiment was conducted using pulsed thermography on a unidirectional carbon laminate piece measuring 33 ✕100 mm. This specimen was intentionally equipped with three artificial delaminations positioned at different depths on specific layers. The results were then compared against conventional approaches such as principal component analysis, partial least-squares regression and polynomial approximation. The findings from this experiment demonstrated the potential of the proposed approach, i.e. the bee colony optimisation coupled with SOM, on the characterisation of discontinuities using infrared thermography data. There was a 15% improvement on the SNR when using the proposed approach over the other tested approaches. This research makes a noteworthy contribution by offering a promising technique for both the detection and characterisation of faults in composite materials.Coordenação de Aperfeicoamento de Pessoal de Nível Superior, National Council for Scientific and Technological DevelopmentConselho Nacional de Desenvolvimento Científico e Tecnológico [407140/2021-2]; Conselho Nacional de Desenvolvimento Científico e Tecnológico [312530/2023-4]; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior [001].Quantitative InfraRed Thermography Journa
Managing sudden unexpected disruptions in complex projects: the antifragility hierarchy
No full textProjects are prone to a variety of sudden unexpected disruptions across their development cycle, requiring that effective organizations develop strategies for proactively recognizing disruption likelihood and swiftly responding to these events. This paper explores a hierarchy of responses to disruption, based on Taleb’s theory of antifragile system behavior. Following this reasoning, we suggest that when faced with project disruptions, organizations need to investigate the means to trigger a ‘convex’ response that increases value through antifragile thinking. We propose an ‘antifragility hierarchy’ in which three key responses to project disruption are demonstrated, with a range of strategies available for addressing these disruptions. This hierarchy offers a novel conceptualization of responses to project disruption events, suggesting that the options available to organizations range from robust (the least effective) to antifragile (the most constructive). Finally, we offer a set of strategies for effectively responding to disruptions to promote antifragility in projects.Production Planning & Contro
A data-driven approach to understanding online service access and technological energy injustice among minority ethnic communities
Get PDFIn the energy domain, various forms of injustice manifest, spanning distribution, production, access, environmental, economic, social, inter-generational, technological, cultural, and governance realms. This paper delves into the technological injustice regarding online service access by energy suppliers, specifically focusing on its impact on energy poverty among minority ethnic communities. The Ofgem Consumer Impacts of Market Conditions Survey Wave 3 Report highlights significant challenges within the energy market, particularly affecting minority ethnic communities. Despite initiatives to investigate legal services for minority ethnic communities, exploration of online service utilization remains inadequate, creating a significant gap in understanding. This paper proposes a comprehensive examination of online service usage and perceptions within minority ethnic communities to address this research gap.
The proposed framework encompasses modules for survey construction, data analysis, Machine Learning (ML) integration, and Agent-Based Modelling (ABM) and simulation. Feature examination reveals correlations between accommodation type and online service satisfaction, influencing simulations. The ABM module simulates how changes in accommodation type affect online service satisfaction, with ML models predicting outcomes. Validation through empirical data and expert knowledge ensures model accuracy.
This research contributes to understanding online service experiences, particularly for minority ethnic communities, aiming to empower researchers and service providers to address inequalities effectively. Future work involves expanding the ABM to incorporate threat modelling concepts, providing a tool for assessing and fortifying the security posture of online services for minority ethnic communities.Engineering and Physical Sciences Research CouncilThis work was supported by the Engineering and Physical Sciences Research Council, part of the UK Research and Innovation (UKRI), under the grant number EP/W032082/1.WSSE 2024: The 6th World Symposium on Software Engineering (WSSE
Comparative analysis of blast prediction software for far-field shock wave effects behind a blast wall
Get PDFThis paper investigates a selection of current and emerging software used in the prediction of overpressure generated through the detonation of a high explosive in the far field behind a blast wall. In particular, this paper compares the software Autodyn, blastFoam, ProSAir, Viper::Blast and WALAIR++. These packages are compared by simulating a 100 kg TNT explosive charge at a stand-off distance of 25 m from a complex structure, then reviewing the performance in terms of the overpressure results, speed of each modelling package, the degree of effect from mesh, and domain sizes and ease of use. A live experimental trial representing the simulation was also performed, although it used a similar but different explosive, for a high-level comparison. The live-trial instrumentation design details are reviewed and compared with best practice. The choice of software is found to lead to variations in peak pressure predictions of 28%, specific impulse by 10% and the simulation speed can vary by a factor of up to 1600 for this type of study. This shows that the choice of blast software package can have a significant impact on the accuracy and attainability of blast predictions.International Journal of Protective Structure
Techno-economic assessment of decarbonization pathways for a gas to liquid facility: a review
Get PDFAn overview of gas-to-liquid (GTL) fuels which explores various approaches to decarbonizing gas-to-liquid facilities is here presented. The review discusses optimization of heat integration in the air separation unit (ASU) to reduce energy requirements, the implementation of loop reactor concepts and gas-to-liquid looping to decrease CO2 emissions, the use of amine absorber/stripper systems and reforming configurations to enhance CO2 consumption, and the utilization of staged Fischer-Tropsch (FT) reactors to improve CO2 recovery and tail gas recycle performance. The integration of gas-to-liquid processes with power plants and ammonia/urea synthesis plants is also examined as a means of utilizing CO2 and improving process economics. The review further highlights the potential of power-based oxygen and hydrogen in biomass-to-liquid (BtL) processes for higher carbon efficiency and reduced greenhouse gas emissions. Techno-economic assessments were reviewed to evaluate the feasibility and profitability of different decarbonization pathways, considering factors such as capital and operational expenditures, product prices, internal rates of return (IRR), and carbon efficiency. The review identified challenges in water treatment and hydrogen purification for gas-to-liquid and small-scale gas-to-liquid plants. The findings emphasized the need for a comprehensive framework to mitigate CO2 emissions from gas-to-liquid facilities and facilitate the effective decarbonization of the oil and gas industry.Journal of CO2 Utilizatio
Expanding organizational routines while preserving professional identity: introducing female officers into combat roles in the Royal Air Force
Get PDFWomen have always played a crucial role in the armed forces. However, they were still banned from taking part in ground combat until 2018. We follow the first female intake into ground combat training within the Royal Air Force and focus on the transition from an all-male to a mixed-gender course.
Our research combines routine dynamics with professional identities; it makes sense as it is individuals who make patterns of action possible, and these individuals are, in turn, embedded in professions which shape their actions (D’Dadderio, 2011; Seele & Grand, 2016).
Our preliminary findings point towards professional identity as a source of stability in routines. Despite attempts by the training design team to incorporate adjustments in the course’s programme, we found that routine participants resisted the changes as it threatened their professional identities
Which factors determine adaptation to drought amongst farmers in Northern Thailand? Investigating farmers’ appraisals of risk and adaptation and their exposure to drought information communications as determinants of their adaptive responses
Get PDFDrought communications constitute an important source of learning about climate risks and responses that can assist adaptation decision-making amongst those whose livelihoods are threatened by drought. This paper applies Protection Motivation Theory to explore associations between drought communications and attitudes towards drought risk and adaptation amongst farmers in Northern Thailand. The analysis reveals links between drought communications, farmers’ adaptation appraisal, and their adaptation decisions, whilst links with risk appraisal are minimal. The results highlight positive feedbacks between adaptation experience and appraisal and reveal a weak negative relationship between risk appraisal and adaptation appraisal. The findings imply benefits to framing drought communications in terms of the efficacy and attainability of suitable adaptations, rather than simply highlighting drought risks or providing drought warnings, to best enable farmers to build drought resilience.Mitigation and Adaptation Strategies for Global Chang