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Grey-box Recursive Parameter Identification of a Nonlinear Dynamic Model for Mineral Flotation
Get PDFA preprint version of the article is available at arXiv:2405.04275v1 [eess.SY] 07 May 2024 (https://arxiv.org/html/2405.04275v1).This study presents a grey-box recursive identification technique to estimate key parameters in a mineral flotation process across two scenarios. The method is applied to a nonlinear physics-based dynamic model validated at a laboratory scale, allowing real-time updates of two model parameters, n and C, in response to changing conditions. The proposed approach effectively adapts to process variability and allows for continuous adjustments based on operational fluctuations, resulting in a significantly improved estimation of concentrate grade - one key performance indicator. In Scenario 1, parameters n and C achieved fit metrics of 97.99 and 96.86, respectively, with concentrate grade estimations improving from 75.1 to 98.69 using recursive identification. In Scenario 2, the fit metrics for n and C were 96.27 and 95.48, respectively, with the concentrate grade estimations increasing from 96.27 to 99.45 with recursive identification. The results demonstrate the effectiveness of the proposed grey-box recursive identification method in accurately estimating parameters and predicting concentrate grade in a mineral flotation process
The YWCA of the USA ‘In Service for the Girls of the World’, 1947-1985
Get PDFBefore mid-century, the Young Women's Christian Association of the USA (Y-US) was complicit with global northern imperial projects, as its work with women across national borders was characterised by an ethos of ‘imperial maternalism’. Applying Serene Khader's (2019) analysis of imperialism in global northern feminisms shows that Y-US's approach to ‘overseas’ work was ‘missionary’ in its use and promotion of ‘western’ values and strategies. Although Y-US inevitably worked within ‘asymmetrical power relations’ (Grewal & Kaplan, 2000, para.4), in the 1970s its approach shifted as it began to recognise these imbalances. By the 1980s, Y-US's ‘global’ programmes sought out women's context-specific knowledge to identify and critique structural inequalities and US imperialism, characteristic of ‘transnational feminist’ ethic. The contribution of Y-US to the YWCA movement was more complex, and positive, than a perpetuation of cultural imperialism. In its national policy and project planning and evaluations, Y-US continued until the 1980s to apply mixture of missionary and transnational feminist lenses to understand its role and responsibilities as a member of the worldwide YWCA movement, and to grapple with the implications of US power on the world stage.Leverhulme Trust, through the British Academy/Leverhulme Small Research Grants Scheme
Assessing the future prospects of emerging technologies for shipping and aviation biofuels: A critical review
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No data was used for the research described in the article.There is an urgent need to switch from fossil to bio-based fuels in the transport sector, particularly in shipping and aviation. The growth of the world's population has resulted in a significant impact on passenger transport, with a noticeable increase in greenhouse gas emissions, depletion of fossil resources and associated risks in all three pillars of sustainability. In this context, new policies, standards and targets have been developed to reduce this environmental damage, which is mainly caused by the use of fossil fuels. Therefore, the alternative of using biofuels seems to be the most appropriate solution, to the extent that important targets have been set and specific directives have been developed for the integration of biofuels in the maritime and aviation sectors. However, to demonstrate that switching to biofuels is indeed beneficial, it is necessary to evaluate new biofuel scenarios from a life-cycle perspective, with particular emphasis on analyses that provide information beyond the present, such as prospective life-cycle assessments. To this end, the focus of this review is on the current trends in the production of biofuels for the marine and aviation sectors, taking into account the main targets set, the existing regulations and directives on the subject, and an analysis of the type of technologies used for their production. It also addresses biofuel Life Cycle Assessment (LCA) scenarios and future LCA approaches, and how these analyses should be carried out to be effective. Finally, key policies, standards and certifications are analyzed. The trends and bottlenecks discussed in this review concerning the actual and future development of the biofuels sector could be used by policy makers and stakeholders to identify efforts that favor the integration of biofuels into the value chain. Furthermore, it could be concluded that the evaluation of the guidelines foreseen in the development of competitive scenarios based on emerging technologies, as well as the adoption of policies and restrictions on the use of fuels, are key conditions to establish the roadmap for the widespread implementation of biofuels.his research has been supported by the project Black Liquor to Fuel (BL2F) project funding from European Union's Horizon 2020 research and innovation program under grant agreement No 884111. A. Arias, G. Feijoo and MT Moreira authors belong to the Galician Competitive Research Group (GRC ED431C 2017/29) and to the Cross-disciplinary Research in Environmental Technologies (CRETUS Research Center, ED431E 2018/01)
A knowledge-based perspective on SME foreign market entry mode choices and changes
Get PDFPurpose:
Despite the importance of foreign market entry mode (FMEM) decisions for the internationalisation of small and medium-sized enterprises (SMEs), there is insufficient understanding of the knowledge types and sources necessary for such decisions. This study addresses this issue by investigating the knowledge configurations that underpin FMEM initial choices and subsequent changes in SMEs.
Design/methodology/approach:
This study adopted an interpretive approach and analysed empirical data from 37 in-depth interviews with decision-makers in internationalised SMEs from the United Kingdom.
Findings:
The findings reveal that different knowledge configurations drive FMEM decisions in SMEs. Based on the analysis conducted for this study, initial FMEM choices draw on prior experiential knowledge combined with knowledge from desk research and knowledge acquired from peers, competitors and international partners. However, unlike many previous contributions, this research shows that foreign market experiential knowledge does not influence mode changes. Within-mode changes rely mainly on mode-specific knowledge and on knowledge about exploiting the benefits of the internet and digital platform ecosystems. Conversely, between-mode changes draw on diverse knowledge that is frequently created in interaction with international stakeholders or acquired externally.
Originality/value:
This study contributes to the SME internationalisation literature by highlighting the knowledge configurations that inform not only initial choices but also between- and within-mode changes. Moreover, it reveals the importance of distinct types of digital technology-based knowledge for facilitating mode changes. It also adds to the knowledge-based perspective by underscoring that dynamic and heterogenous knowledge configurations, often created in interaction with international stakeholders, promote firm internationalisation
Hydrogen Engine Insights: A Comprehensive Experimental Examination of Port Fuel Injection and Direct Injection
Get PDFConference paper presented at WCX SAE World Congress Experience, 16-18 April, 2024, Detroit, MI, USA.Data availability: see: https://saemobilus.sae.org/papers/hydrogen-engine-insights-a-comprehensive-experimental-examination-port-fuel-injection-direct-injection-2024-01-2611#data-sets .The environmental and sustainable energy concerns in transport are being addressed through the decarbonisation path and the potential of hydrogen as a zero-carbon alternative fuel. Using hydrogen to replace fossil fuels in various internal combustion engines shows promise in enhancing efficiency and achieving carbon-neutral outcomes. This study presents an experimental investigation of hydrogen (H2) combustion and engine performance in a boosted spark ignition (SI) engine. The H2 engine incorporates both port fuel injection (PFI) and direct injection (DI) hydrogen fuel systems, capable of injecting hydrogen at pressures of up to 4000 kPa in the DI system and 1000 kPa in the PFI operations. This setup enables a direct comparison of the performance and emissions of the PFI and DI operations. The study involves varying the relative air-to-hydrogen ratio (λ) at different speeds to explore combustion and engine limits for categorising and optimising operational regions.
Furthermore, load sweep tests are conducted at various engine speeds to evaluate the advantages of the H2 direct injection system over the PFI system and to analyse the characteristics of NOx emissions. Additionally, a matrix of inlet and exhaust valve timings is tested for each injection system to assess the valve timings and their interactions with injection setups on combustion, engine performance and emissions. The main findings of this study demonstrate that both PFI and DI hydrogen systems offer the benefit of zero carbon emissions and improved indicated thermal efficiency (ITE) when used in an engine designed and tuned for gasoline combustion. The DI hydrogen system, in particular, exhibits 2% higher ITE than PFI as well as producing higher power output. This enhancement can be attributed to the DI’s ability to operate under stoichiometric conditions, thanks to higher injection pressure and late injection timing during the intake stroke. This configuration mitigates backfire occurrences and prevents hydrogen from bypassing through the exhaust, thus enhancing combustion efficiency.UKRI has funded this research, and the MAHLE Powertrain provides the experimental power unit. Clean Air Power and Phinia provide the Hydrogen Di and PFi injectors, and Cambustion provides the fast NOx emission analyser. Ford Motor Company has managed this project
A novel feed-forward neural network for flow boiling pattern prediction
Get PDFMicroscale flow boiling presents a promising solution to emerging cooling requirements in many applications. Predicting flow boiling patterns could play a key role in the development of new engineering design tools for predicting heat transfer rates and pressure drops. A novel feed-forward neural network architecture was developed to classify flow boiling patterns in the microscale, in which each transition boundary was considered with its own Forward Neural Network within the overall architecture. The network was then compared to new flow boiling pattern data using HFE-7100 for heat fluxes and mass fluxes between 3.2-132.4 kW/m² and 100-1000 kg/m²s, respectively.EPSRC through grant EP/P004709/
The impact of breath-controlled gaming on the quality of airway clearance treatments in children with cystic fibrosis during Project Fizzyo
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Integration of Carbon Emissions Estimates into Climate Resilience Frameworks for Transport Asset Recovery
Get PDFThis study describes a framework for optimizing environmental sustainability, climate resilience, and cost in post-hazard transport asset recovery. Particular focus is given to the environmental impact assessment component and its conceptual integration with resilience metrics. After describing the workflow adopted in the complete framework, the environmental impact modelling assumptions, system boundaries, and life cycle inventories for materials, on-site activities and transportation are detailed. Carbon equivalent emissions are evaluated for various restoration tasks for a bridge subjected to nine flood scenarios and represented through a sustainability index. A baseline environmental impact analysis is initially conducted, considering conventional materials, construction techniques, and procedures for each restoration task. Additional sensitivity studies are carried out to evaluate the influence of low-carbon solutions and task duration on carbon emissions. These are weighted based on the probability of the bridge being in a specific damage state. The results demonstrate that low-carbon solutions can provide carbon savings to varying degrees depending on the hazard intensity. Normalised sustainability, resilience, and cost metrics are combined into a unique global index, which can be adopted to prioritise the recovery of the asset. Suggestions on adopting circularity indicators and waste hierarchy levels into such frameworks are also given.UK Research and Innovation (UKRI) under the Horizon Europe funding guarantee (agreements No. EP/Y003586/1, EP/Y00986X/1, EP/X037665/1), for the project ‘ReCharged - Climate-aware Resilience for Sustainable Critical and interdependent Infrastructure Systems enhanced by emerging Digital Technologies’ (grant agreement No: 101086413)
Leveraging a 7-Layer Long Short-Term Memory Model for Early Detection and Prevention of Diabetes in Oman: An Innovative Approach
Get PDFData Availability Statement: The uniquely constructed Oman Diabetes Type II Screening Dataset, which substantiates the findings of this study, can be made available upon reasonable request by contacting the corresponding author.This study develops a 7-layer Long Short-Term Memory (LSTM) model to enhance early diabetes detection in Oman, aligning with the theme of ‘Artificial Intelligence in Healthcare’. The model focuses on addressing the increasing prevalence of Type 2 diabetes, projected to impact 23.8% of Oman’s population by 2050. It employs LSTM neural networks to manage factors contributing to this rise, including obesity and genetic predispositions, and aims to bridge the gap in public health awareness and prevention. The model’s performance is evaluated through various metrics. It achieves an accuracy of 99.40%, specificity and sensitivity of 100% for positive cases, a recall of 99.34% for negative cases, an F1 score of 96.24%, and an AUC score of 94.51%. These metrics indicate the model’s capability in diabetes detection. The implementation of this LSTM model in Oman’s healthcare system is proposed to enhance early detection and prevention of diabetes. This approach reflects an application of AI in addressing a significant health concern, with potential implications for similar healthcare challenges relating to globally diagnostic capabilities, representing a significant leap forward in healthcare technology in Oman.This research received no external funding. The article processing charges were covered by Brunel University London
Does being a responsible bank pay off? Evidence from the COVID-19 pandemic
Get PDFJEL Classification: G21; G32; M14.Data availability: Data will be made available on request.A preprint version of this paper is available on SSRN at: https://doi.org/10.2139/ssrn.4565590 (also archived on this institutional repository at: https://bura.brunel.ac.uk/handle/2438/27216). It has not been certified by peer review.We investigate whether banks’ initial responses during the first wave of the COVID-19 pandemic in supporting their customers, communities, and governments were perceived as value-enhancing by investors. Using a unique responsible banking measure for a sample of the largest US and European commercial banks, we find a negative relationship between responsible bank behavior and stock market performance, particularly in the first wave of the pandemic. We also find that riskier banks were affected more negatively if they behaved responsibly. Overall, our findings show that banks’ responsible behavior during a crisis reduces, or at best is not relevant to, shareholder value
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