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Assessing the role of servicing in enhancing sanitation-related quality of life among container-based sanitation users
No full textThe data are publicly available via the ReShare service (https://reshare.ukdataservice.ac.uk/857073/): Longitudinal Sanitation Data From High-Frequency Phone Surveys Across Three Countries, 2020–2024.Here we evaluate the servicing of container-based sanitation (CBS)—which includes the collection, replacement and cleaning of cartridges—and its influence on sanitation-related quality of life (using the SanQoL-5 index) in informal settlements across Kenya, Peru and South Africa. We (1) compared the incidence and severity of problems associated with CBS toilets against other sanitation types, (2) assessed the quality of CBS servicing across different regions and implementations and (3) evaluated the relationship between servicing issues and sanitation-related quality of life, utilizing high-frequency longitudinal smartphone survey data collected at various intervals over 1 year. Results revealed significantly fewer and less severe issues were recorded for CBS toilets than other toilet types, such as pit latrines, sewers and open drains. CBS servicing was consistently well regarded in all countries. Participants in Kenya highlighted particular satisfaction with the frequency of container replacement, whereas, in Peru, the cleanliness of replacement containers was highly regarded. SanQoL-5 scores decreased when CBS servicing issues were recorded, particularly in Kenya. This study underscores the potential of CBS as a sustainable sanitation solution in urban informal settlements, provided that high-quality servicing is maintained.This research was undertaken as part of the Scaling-up Off-grid Sanitation project (SOS; grant no. ES/T007877/1), funded with support from the United Kingdom’s Global Challenge Research Fund, via the Economic and Social Research Council.Nature Wate
Examining transfer pricing to improve multinationals’ competitiveness
No full textNnadi, Matthias - Associate SupervisorThis research examines the strategic role of transfer pricing (TP) in enhancing the
competitiveness of multinational enterprises (MNEs), focusing on the interplay between
corporate strategy and international tax compliance. The study synthesizes existing
literature on transfer pricing methods, corporate strategy, and competitiveness, employing
a systematic research approach to assess whether current propositions address the
complexities of TP as a strategic tool beyond mere tax minimization.
The evolution of corporate strategy, driven by theories such as internalization and the
resource-based view, underscores the significance of TP in managing firm-specific
advantages (FSA) and reducing transaction costs. This review highlights that TP not only
serves as a mechanism for tax optimization but also as a strategic instrument for resource
allocation and operational efficiency within MNEs. The research identifies gaps in the
literature concerning the direct link between TP methods and firm competitiveness,
suggesting a need for further empirical and conceptual analysis.
Additionally, the study addresses the implications of international regulatory frameworks,
particularly the OECD’s Base Erosion and Profit Shifting (BEPS) package and the arm's
length principle, on TP practices. It discusses how these regulations influence MNEs'
strategic decisions and competitiveness, emphasizing the challenges and opportunities
presented by compliance requirements.
Highlights
• TP literature has been singly focused on the various calculation methods
• TP is calculated mostly as a cost mechanism
• Tax implications on TP are significant yet unclear and uncertain
• No theory has been created on the direct link of TP methods and the
competitiveness of a firm.MSc by Research in Leadership and Managemen
Recent advances in catalytic conversion of bioethanol to 1,3‐Butadiene: reaction mechanism, catalyst design, and process scalability
No full text1,3-Butadiene (BD), a symmetric C4 diene, is a primary precursor for numerous synthetic rubbers and is sourced largely from the naphtha cracking process. Sustainable BD production from renewable biomass is indispensable for preserving the environment through the circular economy. Ethanol-to-BD (ETB) has particularly witnessed a resurgence in recent years, following two different routes: one-step conversion and two-step process via acetaldehyde. The present review article critically examines the current state-of-the-art research progress of the ETB processes, in terms of historical perspective, reaction mechanism, kinetics, thermodynamics, multifunctional heterogeneous catalysts, reaction parameters, and economic-environmental impact analysis. The ETB processes encompass a complex sequence of reactions on different catalytic sites, including dehydrogenation, carbon–carbon coupling, and dehydration. However, the catalyst with the proper balance between acidic, basic, redox, and metal functionalities (e.g., metal/metal oxide-modified MgO–SiO2 and Zn–Zr mixed oxide), which are uniformly distributed and cooperative, remains a critical challenge in these processes. Despite notable advancements in understanding molecular mechanisms, the design of catalysts for high BD selectivity and process scalability remains the key obstacle to commercial success. The comprehensive summary of ETB process developments provides a foundation for researchers and industry practitioners to advance research and optimize the critical parameters for sustainable BD production.ChemSusChe
Enhancement of radio frequency energy harvesting using embroidery conductive thread and improved power management circuit design
No full textLuk, Patrick Chi-Kwong - Associate SupervisorThe global demand for remotely powering electronic devices without batteries,
particularly for low-power electronics, through ambient RF (Radio Frequency)
energy harvesting is increasing. However, several challenges must be addressed
for Radio Frequency energy harvesting to achieve its full potential in wearable
technology. These challenges include: 1. Maintaining continuous and steady
conductivity of the antenna patch in RF energy harvesting (RFEH) devices. 2.
Enhancing the efficiency of current rectification and power management circuits
at extremely low power levels. This PhD project aims to overcome these
obstacles by employing innovative embroidery conductive thread technology,
which offers more uniform conductivity compared to traditional ink-based
fabrication techniques. Additionally, the project focuses on designing an
improved rectifier for the power management circuit. The proposed rectenna
patch antenna is based on a 50-ohm impedance matching network. The design,
simulation, optimization, and efficiency results of the rectenna patch antenna
were recorded. The fabrication involved creating an efficient patch on both a
textile substrate using conductive threads and a plastic substrate using liquid
metal alloys. An embroidery machine was used for the textile design, while an
inkjet printer was utilized for the plastic substrate. The harvested energy results
were documented, demonstrating an improvement in the current wearable RF
power harvesting system. This study provides valuable insights into materials,
antenna design, and power management systems, advancing the state-of-the-art
in RF energy harvesting and paving the way for further research and
development.PhD in Energy and Powe
Supersonic flow field reconstruction using CNNs
Get PDFThe accurate prediction of a projectile’s aerodynamic coefficients is crucial in high-precision external ballistic calculations. The aerodynamic forces and moments exerted on a projectile in flight influence key performance parameters such as range, accuracy, time of flight and stability. A large body of work has therefore been dedicated to understanding the flow dynamics around projectile bodies and obtaining the critical force and moment coefficients. This has been traditionally achieved in aeroballistic range experiments, wind tunnel set-ups and through the use of numerical models. Nevertheless, a widespread still exists between different techniques, revealing the fluid physics is not yet fully understood.
A better understanding of the aerodynamics at play is accessible through a combination of the three techniques. However, reliable wind tunnel results will require matching a series of similarity parameters imposed by the firing conditions, which will inevitably relate to the physical scale of the models used. The size of small calibre projectiles may prove challenging for measurement in wind tunnel set-ups, however upscaling the models inappropriately will result in unrepresentative flow fields due to wall interactions and blockage effects. On the other hand, sting supports for wind tunnel models disturb a smaller portion of the flow with increasing projectile scale, particularly in terms of wake perturbation - a key contributor to aerodynamic coefficients. Clearly, scale effects have important consequences, however they have not been explicitly treated in the supersonic projectile literature.
This study aims to explore the effects and limits of projectile scaling in supersonic wind tunnels, through a series of experimental techniques (Schlieren visualization, pressure measurements, force balance measurements...) and numerical modelling. Additionally, we aim to develop the Background-Oriented-Schlieren technique a step further through the use of machine learning models to reconstruct complete flow fields from optical data.Royal Higher Institute for Defense, BelgiumDefence and Security Doctoral Symposia 2024 (DSDS24
Data for "Postharvest stress manipulation in Tenderstem® broccoli – examining the potential for stress-adaptative responses to promote sustainable quality retention"
No full textData is provided for floret colour, organic acid and pigment content, and gene expression data for broccoli treated with methyl jasmonate or hydrogen peroxide, and stored at 5 or 10C.Low-temperature postharvest management is utilised to reduce quality and nutritive losses in broccoli after harvest, although this increases postharvest energy demands and the environmental impacts of food supply chain. Hydrogen peroxide (H2O2) and methyl jasmonate (MeJA) have been shown to reduce postharvest yellowing in broccoli by enhancing oxidative stress resistance and were examined as treatments for Tenderstem® broccoli florets for offsetting the effects of warmer storage temperatures. H2O2 elicitation was perceived on a regulatory level through activation of the jasmonate pathway but did not reduce postharvest yellowing. MeJA treatment was detrimental to quality, even at concentrations shown to be beneficial for conventional broccoli varieties. Carotenoid accumulation was shown to be a leading factor in Tenderstem® yellowing during early storage, while photopigment degradation contributed to late-stage quality loss. The physiological basis for floret yellowing in Tenderstem® was also shown to be due to carotenoid accumulation rather than chlorophyll loss. These results highlight the impact of genotypic and developmental effects on stress perception and response, which hinder optimisation of hormesis-based approaches for postharvest management.Biotechnology and Biological Sciences Research Council (BBSRC)Engineering and Physical Sciences Research Council (EPSRC
Blockchain-based data-sharing acceptance among intelligence community
Get PDFData sharing among the intelligence community are critical to enable data analysis in supporting decision making hence preserving the security of the nation. However, sharing data between various parties is complicated due to the confidentiality and the risk of its exposure to unauthorised users and attackers. Hence, application of blockchain technology as a secure data sharing mechanism potentially safeguarding the data. However, the acceptance and readiness of the user to use this technology is questionable. This research aims to identify factors influencing user acceptance and to evaluate the acceptance level of blockchain-based data-sharing among the intelligence community in Malaysia by integrating Technology Acceptance Model 3 and Technology Readiness Index 2.0. This study applied an extensive literature review and empirical research using a survey questionnaire of data from 210 respondents from the intelligence communities. Descriptive and demographic data analysis using IBM SPSS software version 27 was used in this study. The acceptance model is analysed and verified using PLS-SEM method by using SmartPLS version 3.3.2. The results indicate that 10 out of 12 hypotheses is accepted and the acceptance is below moderate level. Hence, personality traits and feeling influenced the acceptance of the blockchain-based data-sharing system in the intelligence community. Overall, the result can assist the administration to manage the technology implementation process and to provides the system and architecture requirement in developing blockchain-based data sharing for the use of the intelligence community.Defence and Security Doctoral Symposia 2024 (DSDS24
Development of a method to classify and analyse the composition of mixed waste materials in real-time
Get PDFLonghurst, Philip J. - Associate SupervisorThere is a need for innovative technologies to classify and monitor the
composition of solid waste in real-time. This research project has highlighted
which information is required to improve current process designs. It also identified
visible spectrum cameras as the solution that can better inform waste
composition and quality without requiring complementing technologies. The
experiments applied deep learning methods to classify the materials based on
their images, and a method to analyse the composition of mixed waste was
developed.
There is a high variability in the appearance of waste materials in the context of
a material recovery facility. An image capture setup using multiple cameras and
light sources was implemented and tested to acquire a representative set of
images. The hardware captures images from different angles, with enhanced
shadow details, and different exposure levels. Image processing software further
augmented the data by rotating and changing the images resolutions. The images
were converted to greyscale to increase the method robustness without affecting
classification performance.
Deep convolutional neural networks were trained on the augmented datasets.
The trained networks obtained state-of-the-art performance when tested and
validated for the task of waste material classification. Based on this, a
composition analysis methodology was developed and tested with mixed material
samples. The methodology provides results as accurate as current manual
solutions, but it can analyse a waste stream on a conveyor belt in real-time. The
findings and observations from the experimental results contribute to knowledge
in three main areas: data capture, data processing, and deep learning.
This thesis presents the progressive development of the methodology and
discusses different applications for waste management. The composition
analysis can provide real-time waste data to improve the overall efficiency of the
waste treatment industry. This information can be also used by stakeholders for
better decision-making in the future.PhD in Energy and Powe
Design, development and testing of a high-pressure hydrogen micromix combustion rig
No full textThe aviation industry has been improving aircraft performance and cutting back
emissions for decades now. The increasing urgency of climate change has been
pushing this effort to become more intense leading in recent years to the adoption
of the target of full decarbonisation by 2050. Significant reductions in non-carbon containing
emissions have been targeted by the industry as well.
In that context, the use of liquid hydrogen (LH₂) as a combustible fuel for aircraft
propulsion is a promising solution. Hydrogen guarantees carbon-free flights at mission
level, yet, state-of-the-art aircraft combustor technologies are not suitable for
low-NOₓ hydrogen combustion. Consequently, alternative combustion concepts and
technologies are under research, and micromix technology is one of them.
This thesis presents the design, development and deployment of a high-pressure
combustion rig for hydrogen micromix burners, and describes the process from conception
to testing of three different injector geometries. In doing so, it highlights
the challenges of designing the components and systems to operate with hydrogen,
whilst ensuring safety. Based on the experience gained through the deployment of
the experimental setup, potential problems have been identified and solutions have
been suggested to improve it. This aspect of the work contributes towards future
research efforts of developing larger-scale combustion rigs for testing hydrogen.
Within the context of the rig development, different design philosophies and manufacturing
routes are explored for micromix burners. The limitations and safety
considerations for the different approaches are detailed, and guidelines are offered
on how the setup may be improved. The successful implementation of a fabrication
strategy that combines additive manufacturing with traditional machining of
features with sub-millimetre dimensions (0.3mm) is a significant contribution to
developing micromix burners. It further opens an area of research into the limitations
and potential effects of applying additive manufacturing to future micromix
combustors.
NOₓ emissions measurements of three injector configurations with different momentum
flux ratios (MFRs) taken at elevated pressures, air-inlet temperatures and
equivalence ratios are presented. The results denote the impact of these parameters
on NOₓ emissions and the sensitivity of the emission to changes in MFR.
Comparisons with LES results further highlight the need to accurately represent
phenomena that affect the momentum flux ratio (MFR) in the simulations. Failure
to do so provides a misleading correspondence of NOₓ levels with MFR. When compared
to a state-of-the-art kerosene burner at similar pressure and inlet temperature
conditions, hydrogen micromix yielded lower NOₓ by 50% for the ”worst” injector
configuration.PhD in Aerospac
Promoting global collaboration to improve bioaerosol exposure assessment and understanding of associated health impacts: outcomes from a series of workshops
Get PDFWe are surrounded, in both indoor and outdoor environments, by air containing particles of biological origin (bioaerosols). We constantly inhale them, and, depending upon their size, they deposit in different parts of our airways. Despite their ubiquitous nature and our constant exposure, bioaerosol diversity and composition of the environment are not well characterized, and we understand little about which bioaerosols we are exposed to and how this impacts our health, either positively or negatively. Indoor/Outdoor Bioaerosols Interface and Relationships Network (BioAirNet), a Clean Air Programme-funded network, has recognized the need for the bioaerosol community to reflect on the current challenges facing bioaerosol exposure assessment and the determination of the associated cellular/molecular responses driving specific health outcomes. A series of online workshops for the bioaerosol community were hosted by BioAirNet in September 2022, which aimed to bring together global expertise to discuss the current challenges impeding improved assessment of bioaerosol exposure and understanding of the downstream cellular and molecular mechanisms driving health outcomes by discussing these challenges; considering where we need to be, where we are now and how we get there. Professional facilitation was key to their success, enabling the multidisciplinary bioaerosol community to explore and address these challenges within a focused and productive environment to prioritize themes and agree on action plans for continued momentum following the workshops. These themes were as follows: (1) conceptual model; (2) stakeholder mapping; (3) knowledge transfer; (4) writing project and (5) conference-type event, collectively covering research, knowledge mobilization and networking activities. A subsequent in-person follow-up workshop was held in November 2023. It provided an opportunity to share progress on the five themes, critique what had already been done and act as a launch-pad to progress the actions further. Delegates also had the opportunity to share ongoing or upcoming work, particularly projects requiring input from others, to encourage collaborative working and sharing expertise. The use of facilitated workshops is a valuable tool for all scientific communities to collectively explore and successfully address key issues within their field.These workshops and associated work were funded by the indoor/outdoor bioaerosols interface and relationships network (BioAirNet), funded by UK Research and Innovations grant (NE/V002171/1).Microbiolog