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Data file for Pyrola journal paper
No full textPyrolysis GC-MS testing of excavated landfilled plastics as part of an EPSRC-funded PhD project.Engineering and Physical Sciences Research Council (EPSRC
Towards high resolution absolute angle sensing using dual-wavelength laser speckle
Get PDFWe present a two dimensional angle sensor with greater than 0.01 degrees resolution, using dual-wavelength laser speckle. The technique uses speckle correlation of a double speckle pattern, determining absolute surface tilt from a single frame. A constructed sensor was used to measure a grid of 2D angles between ±0.25° rotating around both x and y axes. Sensor performance was limited by laser mode instability effects, however an analysis of measurements demonstrated that a stable mode output could achieve bias errors of less than 0.010°, and standard deviations of 0.003° around x and 0.021° around y .This work was supported by the Engineering and Physical Sciences Research Council (EPSRC) UK [EP/S01313X/1, EP/R512515/1]2024 IEEE International Instrumentation and Measurement Technology Conference (I2MTC
Uncovering the impact of metals on the formation and physicochemical properties of fat, oil and grease deposits in the sewer system
Get PDFThe deposition of fats, oil, and grease (FOG) in sewers reduces conveyance capacity and leads to sanitary sewer overflows. The major contributing factor lies in the indiscriminate disposal of used cooking oil (UCO) via kitchen sinks. While prior investigations have mostly highlighted the significance of Ca2+ from concrete biocorrosion, the influence of common metal ions (e.g., Mg2+, Na+, K+) found in kitchen wastewater on FOG deposition has received limited attention in the existing literature. This study aimed to elucidate the roles of Ca, Mg, Na and K in FOG deposition in sewers and examine the influence of metal ions, fat/oil sources, and free fatty acids (FFAs) on the physicochemical and rheological properties of FOG deposits. To examine FOG deposit formation, synthetic wastewater containing 0.1 g/L of each metal ion was mixed with 40 mL of fat/oil and agitated for 8 h. Following FOG deposition, three distinct phases were observed: unreacted oil, FOG deposit and wastewater. The composition of these phases was influenced by the composition of metal ions and FFA in the wastewater. Mg produced the highest amount of FOG of 242.5 ± 10.6 mL compared to Ca (72.5 ± 3.5 mL) when each FFAs content in UCO was increased by 10 mg/mL. Molar concentration, valency and the solubility of metal ion sources were identified to influence the formation of FOG deposits via saponification and aggregation reaction. Furthermore, Fourier-Transform Infrared spectroscopy indicated that the FOG deposits in this study were similar to those collected from the field. This study showed that the use of Mg(OH)2 as a biocorrosion control measure would increase FOG deposition and highlights the need for a comprehensive understanding of its roles in real sewage systems.Fujian Institute of Research on the Structure of Matter, Department of FinanceChemospher
Practices and challenges of safety management in outsourced facilities management
Get PDFIntroduction: Outsourcing is a commonly occurring organizational activity, but one associated with negative occupational safety outcomes. Improving the management of safety in workplaces where contractors are employed is vital, but under-researched in the service sectors. The aims of this paper were to investigate both the practices and challenges of safety management in outsourced facility management (FM), an important global service sector. Method: Twenty-three semi-structured interviews were conducted with clients and contractors in three different FM outsourcing arrangements between large corporations in the UK. Data were thematically coded against frameworks derived from existing literature to identify deployed safety management practices and reveal challenges associated with safety management in these outsourced relationships. Results: Safety management practices in outsourced FM conformed to known practices clustering into four previously identified categories (planning, selecting, on-site working, and checking). A fifth category (reviewing) was not observed. Operating across national boundaries, applying national contracts locally, working with mandated KPIs, and contract specifications all created new challenges for safety management not previously reported. Other known challenges associated with economic pressure and disorganization were observed. Conclusion: Safety management practices observed in safety critical industries also apply in FM. However, the challenges of safety management in these three cases included regulatory failures that have not been routinely identified in other empirical studies of safety in outsourcing arrangements. Practical application: Adopting widely accepted safety management practices support safer working in outsourced FM and encourage cross-sector learning. New challenges for safety management noted here encourage consideration of unintended consequences of contract terms and conditions, require corporate agreement on how to ensure safety compliance when working transnationally, and a review of decision-making and processes and procedures to enable effective and safe working locally.Institution of Occupational Safety and Health (IOSH), UKJournal of Safety Researc
Evaluating cause-effect relationships in accident investigation using HFACS-DEMATEL
No full textThis paper addresses the ‘routes to failure’ in the causal chain of events as categorized using the Human Factors Analysis and Classification System (HFACS) framework. By using the Decision-Making Trial and Evaluation Laboratory (DEMATEL) method to evaluate the comparative influence of each HFACS category on other categories, the present research aims to classify each HFACS category as either an overall ‘cause’ or an overall ‘effect’ factor, and to give each HFACS category a comparable statistical value of their overall level of influence. Analysis of N = 30 responses from aviation safety experts identified that frontline perception faults had the potential to influence higher-level preconditions, and that ‘Environmental Factors’ were found to have the highest overall influence amongst HFACS categories at levels 1 and 2. The findings support the use of the DEMATEL method in the selection and direction of safety interventions. Safety remedies focusing on ‘cause’ factors are likely to have additional second-order benefits on associated ‘effects’, and more influential categories are likely to be more effective in influencing overall system safety. The methodology can assist safety managers in selecting and prioritizing safety initiatives, especially when faced with issues such as monetary or time constraints in the industrial context.21st International Conference, EPCE 2024, Held as Part of the 26th HCI International Conference, HCII 202
Predictive maintenance servitisation pathways
Get PDF6th IFAC Workshop on Advanced Maintenance Engineering, Services and Technology AMEST 2024, 12-14 June 2024, Cagliari, ItalyThe competition within the manufacturing industry is becoming increasingly intense in the Industry 4.0 era. Some manufacturers are transforming their traditional product-selling business model into product-service combos to gain customer loyalty and new sources of revenue through the so-called manufacturing servitisation. Predictive maintenance (PdM) is a strategy that significantly overlaps with manufacturing servitisation in terms of enabling technologies, including IoT, Big Data, Cloud Computing, etc. PdM is expected to both maximise productivity and minimise maintenance costs. Although much attention has been given to PdM and manufacturing servitisation, previous studies have ignored the synergy of PdM and manufacturing servitisation. This paper highlights the importance and feasibility of implementing PdM servitisation. Additionally, by analysing practical PdM servitisation cases, three PdM servitisation pathways are defined. Finally, the defined pathways are discussed, and future research directions are proposed.6th IFAC Workshop on Advanced Maintenance Engineering, Services and Technology AMEST 2024IFAC-PapersOnLin
CCS0025: Written evidence for the Environmental Audit Committee of the UK Parliament in relation to climate change and security
No full textOpen Parliament Licence https://www.parliament.uk/site-information/copyright-parliament/open-parliament-licence
The role of mixing on the kinetics of nucleation and crystal growth in membrane distillation crystallisation
Get PDFWhile mixing is considered critical in membrane distillation crystallisation, an explicit link between mixing and crystallisation mechanisms has yet to be made. This study therefore used in-line nucleation detection to determine induction time and metastable zone width, as a method to characterise the independent roles of interfacial boundary layer mixing and bulk crystalliser mixing on the kinetics of nucleation and crystal growth in membrane distillation crystallisation. Interfacial boundary layer mixing was investigated by changing Reynolds number (Re, 1300–2050), where an increase in Re also increased flux. This increased supersaturation within the boundary layer, shortened induction time, and was correlated to a higher nucleation rate. The high nucleation rates introduced smaller crystal sizes, which is an effect that can be correlated to classical nucleation theory. Mixing within the crystalliser did not modify the interfacial supersaturation at nucleation (ReN 1562–18741). However, a decrease in induction time was observed when transitioning from lower to higher mixing, which may arise from the improved distribution of the supersaturated feed within the crystalliser. The effect of crystalliser mixing was also evident on crystal growth, where larger crystals were produced at higher crystalliser stirrer speeds due to improved diffusion-controlled growth. This study therefore demonstrates that bulk and interfacial mixing can be collectively used to control crystallisation by decoupling conditions that determine nucleation and crystal growth. Morphological assessment was subsequently undertaken that evidenced how dendritic breeding and wider secondary nucleation mechanisms that dominate crystal growth at high levels of supersaturation can be mitigated through mixing. Membrane crystallisation offers a scalable geometry in which we demonstrate mixing to facilitate good control over crystal growth which is more difficult to realise in existing evaporative crystalliser design.European Research CouncilSeparation and Purification Technolog
Simultaneous optimisation of vehicle design and control for improving vehicle performance and energy efficiency using an open source minimum lap time simulation framework
Get PDFThis paper presents a comprehensive framework for optimising vehicle performance, integrating advanced simulation techniques with optimisation methodologies. The aim is to find the best racing line, as well as the optimal combination of parameters and control inputs to make a car as fast as possible around a given track, with a focus on energy deployment and recovery, active torque distribution and active aerodynamics. The problem known as the Minimum Lap Time Problem is solved using optimal control methods and direct collocation. The solution covers the modelling of the track, vehicle dynamics, active aerodynamics, and a comprehensive representation of the powertrain including motor, engine, transmission, and drivetrain components. This integrated simulator allows for the exploration of different vehicle configurations and track layouts, providing insights into optimising vehicle design and vehicle control simultaneously for improved performance and energy efficiency. Test results demonstrate the effect of active torque distribution on performance under various conditions, enhanced energy efficiency and performance through regenerative braking, and the added value of including parameter optimisation within the optimisation framework. Notably, the simulations revealed interesting behaviours similar to lift-and-coast strategies, depending on the importance of energy saving, thereby highlighting the effectiveness of the proposed control strategies. Also, results demonstrate the positive effect of active torque distribution on performance under various conditions, attributed to the higher utilization of available adherence. Furthermore, unlike a simpler single-track model, the optimal solution required fine control of the active aerodynamic systems, reflecting the complex interactions between different subsystems that the simulation can capture. Finally, the inclusion of parameter optimisation while considering all active systems, further improves performance and provides valuable insights into the impact of design choices.World Electric Vehicle Journa
Rapid climate change, integrated human–environment–historical records and societal resilience in Georgia
Get PDFIn the midlatitudes of the planet, we are facing the imminent disappearance of one of our best high-resolution (pre)historic climate and anthropogenic pollution archives, namely the loss of glacial ice, through accelerated global warming. To capture these records and interpret these vanishing archives, it is imperative that we extract ice-cores from midlatitude regions where glaciers still survive and analyse them within frameworks of inter-disciplinary research. In this paper, we focus on Georgia, part of the Greater Caucasus. Results of ice-core analyses from the region have never, to date, been integrated with its other abundant palaeo-environmental, archaeological and historical sources. We review the results of international projects on palaeo-environmental/geoarchaeological sediment archives, the archaeology of metal economies and preliminary ice-core data in Georgia. Collectively, we show that the different strands need to be integrated to fully explore relationships between climate/landscape change and human societal transformations. We then introduce an inclusive interdisciplinary framework for ongoing research on these themes, with an ultimate future goal of using data from the past to inform societal resilience strategies in the present.Research EnglandWe are very grateful to the Research England-University of Nottingham Global Challenges Research Fund (QR), award 2114365, for funding preliminary Kazbegi ice-core research in 2021, and to the University of Nottingham International Research Collaboration Fund, award 20280929, to further develop the research in July 2023.We are also grateful to the Climate Change Institute, University of Maine for supporting a PhD linked to the project and for provision of funding in kind. We are thankful to the EU fellowship for Georgian Researchers 2023 program and Shota Rustaveli National Science Foundation of Georgia (project# FR-18-22377). The French CNRSD and École Normale Supérieure provided additional opportunities for networking.Sustainabilit