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Transitioning to low carbon construction: a review of blast and fragmentation impact research related to terrorist threats
Get PDFAs countries tackle climate change by aiming to reach net-zero carbon, the construction industry faces a substantial challenge to reduce carbon emissions in infrastructure, whilst maintaining safety standards. This review initially explores the sustainability targets and the evolving terrorist threat landscape and trends. A systematic search identifies research publications around blast and ballistic/fragmentation impact testing of materials. It then focusses on low carbon material variants, ‘carbon sink’ products and materials where design efficiency can reduce carbon content. Whilst this review shows that blast, ballistic and impact performance research of low carbon construction materials is a growing topic, currently the testing of products against relevant threats lags implementation. Design and test standards for these materials are still limited, resulting in difficulties for building owners to assess the risk and implement an adequate safety plan against terrorist threats. The greatest area where research and test standards are lacking is around cladding, especially for modular or off-site buildings which have a wide variety of material options. This review concludes with suggestions for further research to understand the vulnerabilities of these building materials against terrorist threats.This work was supported by the British Army [External Placements (Academic) Full-time Programme] and Cranfield Forensics Institute.Structure
The aeropolitical realities underpinning the formation of an asean single air market
Get PDFPagliari, Romano - Associate SupervisorThis study investigated regional air transport liberalisation in Southeast Asia
based on a mixed-methods approach which incorporated a pilot survey (n=10),
an online expert survey (n=50) and in-depth interviews (n=15), while employing
a strategic framework adapted for this study called the Aeropolitical Regional
Integration Framework (ARIF). The Association of Southeast Asian Nations
(ASEAN) has significantly promoted regional air transport liberalisation. This
initiative is an integral part of the ASEAN Community project, designed to
enhance connectivity and economic development that contribute to building a
regional identity. However, despite initial progress, the regional open skies
agreement known as the ASEAN single aviation market (ASAM) has not unfolded
as anticipated, with existing literature suggesting that aeropolitical challenges are
among the primary reasons for this. The hybrid thematic analysis of the data,
incorporating both inductive and deductive approaches, has identified key
aeropolitical barriers and opportunities from political economy, geopolitics, and
geoeconomics dimensions. Additionally, the research identifies mechanisms
ASEAN employs to mitigate these challenges and capitalise on the opportunities.
Within this study, aeropolitics emerges from the dynamic interplay among diverse
state entities, with a particular emphasis on power relations among smaller
nations and superpowers, as well as non-state actors, including those beyond the
aviation sector, across various levels — national, intraregional, and interregional
— which collectively exert influence over the aviation market. Despite the strong
influence of politics in the region, it also reveals a genuine desire within ASEAN
for meaningful liberalisation of air markets. While ASEAN may not replicate the
European-style single aviation market model, there is clear evidence that regional
divisions and obstacles gradually diminish over time. The ASEAN Way is not
inertia in disguise but rather progress in a different form, where ASEAN does not
aim to establish a single regulatory institution but pursues advanced cooperation
within its member states and regional partners.PhD in Transport System
Assessment of a liquid hydrogen conditioning system for retrofitting on kerosene designed turbofans
Get PDFAs energy transition to alternative fuels for civil aviation is likely to be gradual, hydrogen’s first entry to service may be implemented on existing gas turbine engines. In this paper a novel liquid hydrogen conditioning system for retrofitting on kerosene designed geared turbofans is assessed in terms of performance and engine rematching. The aim of the analysis is to identify emerging requirements for the design of the fuel and thermal management system within the constraints of a certified engine design. The conditioning system proposed, an LH2 preheater, enables the control of the gaseous hydrogen temperature at combustor entry and consists of a secondary combustor and a heat exchanger. The examined configuration considers various bleed source locations within the engine to supply the preheater system. For performing the analysis, a kerosene fueled engine has been designed and suitable integrated models capable to simulate the retrofitted hydrogen fueled engine as well as the LH2 preheater operation have been developed. The system performance has been analyzed for the different bleed source locations identifying operating limits and performance changes. From all the examined bleed source positions, utilizing the by-pass duct minimizes the impact on component rematching and engine efficiency. Additionally, through a gas path geometry multiparametric analysis, it was found that by readjusting the capacity of the high-pressure turbine and the core nozzle area the certified limits can be met for the retrofitted engine.Alan Turing Institute (113263)ATI/iUK (UKRI, PINES project — Reference No. 113263; Funder ID: 10.13039/501100006041).Journal of Engineering for Gas Turbines and Powe
Synergistic aerodynamic force assessment through an extended exergy approach
Get PDFSanders, Drewan S. - Associate SupervisorDrag decomposition using energy and exergy-based methods has shown large utility for
aerodynamic performance assessment through their flow-field decompositions into different
physical mechanisms. A particularly significant advantage of these methods is their ability to
identify recoverable energy, which describes the available energy imparted to the flow by the
aircraft as it traverses through the fluid. This type of assessment is not possible with traditional
momentum analysis. Thus, energy/exergy analysis uniquely evaluates the potential benefits of
wake energy utilisation for thrust production through novel architectures such as boundary layer
ingestion. The velocity decomposition approach has introduced notable improvements to this
analysis framework. This allows for a phenomenological drag decomposition into reversible and
irreversible components by splitting the velocity field into its isentropic and non-isentropic
contributions within the flow. From this, the reversible drag originating from the bulk flow can be
obtained through the isentropic field, whilst the non-isentropic field provides the irreversible
dissipative drag arising from the boundary layer and wake zones. The work conducted in this thesis
aims to improve the velocity decomposition approach by combining it with partial pressure field
analysis, enabling the decomposition of pressure into Euler and dissipative parts, previously not
achievable with velocity decomposition alone. Assessment in this manner improves the evaluation
of recoverable energy by identifying the additional pressure work potential within the dissipative
field. Additionally, the unification extends energy/exergy-based analysis principles to the near-
field, providing a unique decomposition capable of evaluating the local accumulation of viscous
drag through dissipative pressure and skin friction, whilst the induced drag is assessed from the
non-dissipative pressure.PhD in Aerospac
A review on upcycling waste cooking oil into polyhydroxyalkanoates (bioplastic): a pathway for sustainable material
No full textWaste cooking oil (WCO) improper disposal leads to water pollution, ecosystem disruption, and human health hazards. Various upcycling strategies have been explored, including conversion to biodiesel, surfactants, and biodegradable polymers. Converting WCO into polyhydroxyalkanoates (PHAs), biodegradable and biocompatible bioplastics, offers a sustainable solution aligned with circular economy principles. WCO usually requires minimal or no pretreatment and can be effectively used as a carbon source for microbial fermentation. Free fatty acids (FFAs) from WCO are readily metabolized by PHA producing bacteria such as Cupriavidus necator and Pseudomonas spp., enabling PHA accumulation ranging from 27 % to 96 % (w/w). Depending on the microbial strain and fermentation strategy, both short chain length (scl-PHA) and medium chain length (mcl-PHA) polymers with varied properties can be synthesized. The coproduction of other products, such as carotenoids and surfactants, may further improve the process economics. However, variability in the composition of various oils can cause inconsistent productivity and monomer distribution, highlighting the need for thorough feedstock characterization. Insights from recent studies highlight that oils rich in long chain unsaturated fatty acids (LCFA), such as rapeseed or canola oil, enable the highest biomass and PHA yields, while oils dominated by medium chain saturated fatty acids (MCFA) favor flexible mcl-PHAs but with lower productivity. Integrating artificial intelligence (AI) and machine learning could further improve predictive analysis, process control, and strain selection. This review emphasizes the importance of aligning feedstock composition, microbial selection, coproduction, and improved fermentation strategies to advance sustainable PHA production from WCO.This work was supported by the National Research Foundation of Korea (NRF) [NRF-2022M3I3A1082545 & NRF-2022R1A2C2003138] and the R&D Program of MOTIE/KEIT [02311604, RS-2025-09312968 and 00467186].International Journal of Biological Macromolecule
Alternative metallocenes in floating catalyst-CVD: synthesis of novel carbon nanostructures
No full textIntroduction: The floating catalyst chemical vapour deposition (FC-CVD) method is widely used for synthesising carbon nanotubes (CNTs), typically with ferrocene as the catalyst. This study explores the use of alternative, nonferrous metallocenes to investigate their impact on carbon nanostructure formation. Methods: Six metallocenes - ferrocene, cobaltocene, ruthenocene, vanadocene, manganocene, and magnesocene - were tested under comparable FC-CVD conditions. The resulting materials were characterised using scanning electron microscopy (SEM), Raman spectroscopy, and energy-dispersive X-ray spectroscopy (EDS). Results and Discussion: Ferrocene produced vertically aligned CNT carpets with high crystallinity. Cobaltocene and magnesocene also yielded CNTs, though less aligned and more defective. Ruthenocene and vanadocene resulted in disordered graphitic carbon without nanotube morphology, confirmed by the presence of broad D and G bands in Raman spectra. Notably, manganocene catalysed the formation of dendritic structures with oxidised and functionalised surfaces, exhibiting unique morphologies distinct from conventional CNTs. Conclusion: These results highlight the ability of nonferrous metallocenes to direct the growth of unconventional carbon nanostructures. The findings suggest new possibilities for tailoring nanocarbon morphology through catalyst selection, particularly for applications requiring high surface area or chemical functionality.This research was funded by Warsaw University of Technology IDUB, POB Materials Technologies – 3 ADVANCED grant no1820/359/Z01/POB5/2021.Nanotechnology, Science and Application
Computational fluid dynamics and potential flow modelling techniques for floating photovoltaic systems: a systematic review
No full textLand availability constraints limit the installation of conventional ground-mounted solar installations. As a result, Floating Photovoltaic (FPV) systems are gaining popularity as an alternative to renewable energy generation. FPV consist of individual solar panels that are commonly symmetrical and modular. However, the hydrodynamic behaviour of FPVs in water surface waves is understudied to ensure their stability and optimal performance under varying environmental conditions. This literature review examines various modelling techniques applied in studying FPV hydrodynamics. Specifically, the application of Computational Fluid Dynamics (CFD) solvers and potential flow theory solvers is investigated for their effectiveness in capturing the behaviour of FPVs and mooring dynamics under the impact of wind and waves. The review highlights the advantages and limitations of each approach. Findings suggest that a combined CFD-potential flow approach offers a perfect balance between accuracy and computational efficiency, offering valuable insights into the performance of FPVs. However, extensive research is notably absent in hydrodynamic modelling for large-scale FPVs. This lack of research represents a significant gap in our current study on multiscale FPV systems.Symmetr
Autonomous vehicle adoption and supply chain social sustainability: Delphi study and expert interviews
Get PDFPurpose
Autonomous vehicle (AV) adoption has both positive and negative impacts on supply chain social sustainability (SCSS). This paper explores and evaluates the actions that organisations take to address the social impacts of adopting AVs and develops a model for SCSS in this context.
Design/methodology/approach
This study implemented a Delphi study conducted over three iterative rounds to gather and evaluate the actions that organisations take to address social impacts when adopting AVs in supply chains. The panel consisted of 39 experts from industry and academia. The Delphi findings are validated and extended through 14 follow-up expert interviews.
Findings
Our findings identify eight categories of actions used to address the social impacts of adopting AVs in the supply chain. These are discussed in relation to established SCSS indicator categories and an additional category, “reputation” is introduced. The categories are also aligned to the technology adoption process to understand how social sustainability implications can be mitigated as AV adoption matures.
Practical implications
Practitioners benefit from prescriptive frameworks which provide actions addressing the social sustainability implications of AV adoption. These can be applied either from a social sustainability indicator or innovation adoption process perspective.
Originality/value
This study builds on the diffusion of innovation (DOI) theory to propose a refined innovation process model for socially sustainable adoption of AVs. This customised model aligns the new action categories with the established stages of the innovation adoption process, uniquely illustrating how to manage the social sustainability impacts of AV adoption as part of the technology adoption process. Identified social supply chain indicator categories are also aligned with the actions for an alternative perspective.International Journal of Physical Distribution & Logistics Managemen
Advanced thermal imaging processing and deep learning integration for enhanced defect detection in carbon fiber-reinforced polymer laminates
Get PDFCarbon fiber-reinforced polymer (CFRP) laminates are widely used in aerospace, automotive, and infrastructure industries due to their high strength-to-weight ratio. However, defect detection in CFRP remains challenging, particularly in low signal-to-noise ratio (SNR) conditions. Conventional segmentation methods often struggle with noise interference and signal variations, leading to reduced detection accuracy. In this study, we evaluate the impact of thermal image preprocessing on improving defect segmentation in CFRP laminates inspected via pulsed thermography. Polynomial approximations and first- and second-order derivatives were applied to refine thermographic signals, enhancing defect visibility and SNR. The U-Net architecture was used to assess segmentation performance on datasets with and without preprocessing. The results demonstrated that preprocessing significantly improved defect detection, achieving an Intersection over Union (IoU) of 95% and an F1-Score of 99%, outperforming approaches without preprocessing. These findings emphasize the importance of preprocessing in enhancing segmentation accuracy and reliability, highlighting its potential for advancing non-destructive testing techniques across various industries.This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior—Brazil (CAPES)—Finance Code 001. H.F. gratefully acknowledges the financial support of CNPq (Grants #312530/2023-4 and #407140/2021-2).Material
High foot traffic power harvesting technologies and challenges: a review and possible sustainable solutions for Al-Haram Mosque
Get PDFThe growing global demand for sustainable energy solutions has led to increased interest in kinetic energy harvesting as a viable alternative to traditional power sources. High-foot-traffic environments, such as public spaces and religious sites, generate significant mechanical energy that often remains untapped. This study explores energy-harvesting technologies applicable to public areas with heavy foot traffic, focusing on Al-Haram Mosque in Saudi Arabia—one of the most densely populated religious sites in the world. The research investigates the potential of piezoelectric, triboelectric, and hybrid systems to convert pedestrian foot traffic into electrical energy, addressing challenges such as efficiency, durability, scalability, and integration with existing infrastructure. Piezoelectric materials, including PVDF and BaTiO3, effectively convert mechanical stress from footsteps into electricity, while triboelectric nanogenerators (TENGs) utilize contact electrification for lightweight, flexible energy capture. In addition, this study examines material innovations such as 3D-printed biomimetic structures, MXene-based composites (MXene is a two-dimensional material made from transition metal carbides, nitrides, and carbonitrides), and hybrid nanogenerators to improve the longevity and scalability of energy-harvesting systems in high-density footfall environments. Proposed applications for Al-Haram Mosque include energy-harvesting mats embedded with piezoelectric and triboelectric elements to power IoT devices, LED lighting, and environmental sensors. While challenges remain in material degradation, scalability, and cost, emerging hybrid systems and advanced composites present a promising pathway toward sustainable, self-powered infrastructure in large-scale, high-foot-traffic settings. These findings offer a transformative approach to energy sustainability, reducing reliance on traditional energy sources and contributing to Saudi Arabia’s Vision 2030 for renewable energy adoption.Applied Science