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Comparative life cycle assessment of aluminium and CFRP composites: the case of aerospace manufacturing
Get PDFAs climate change intensifies and existing resources are depleted, the need for sustainable industries becomes more important. The aviation industry is actively addressing environmental concerns by enhancing fuel efficiency and adopting lighter materials, especially carbon fibre composites. Research has proven that the use of carbon fibre composites provides cumulative benefits in reducing fuel consumption over the entire life cycle of an aircraft. However, existing studies are lack of a comprehensive exploration of the diverse impacts associated with composite manufacturing processes and recycling methods. To address this gap, a comparative life cycle assessment analysis covering the materials’ manufacturing, operation, and end-of-life phases is conducted. This analysis includes aluminium alloy and five different carbon fibre composite materials produced with varied constituents and manufacturing methods. Composite manufacturing processes, encompassing carbon fibre production, resin selection, and composite manufacturing methods, are considered. Weight savings based on the mechanical properties of utilised composite type are also taken into account. Results highlight the potential to mitigate the environmental impact of composite materials through strategic choices in constituent types, manufacturing processes, and disposal scenarios. Moreover, break-even distances indicate that aluminium becomes more environmentally detrimental than the analysed composite structures beyond a flight distance of 300,000 km.The International Journal of Advanced Manufacturing Technolog
The relationship between spatial configuration of urban parks and neighbourhood cooling in a humid subtropical city
Get PDFContext
Urban parks are essential for maintaining aesthetics within cities and keeping their its energy balance by helping mitigate the Urban Heat Island (UHI) effect through controlling ambient and land surface temperature (LST).
Objectives
To investigate the impact of cooling in terms of distance by variously configured urban parks of a humid subtropical city, using landscape metrics and open-source data.
Methods
Land use (LU) was obtained through maximum likelihood classification of 3 m resolution aerial RGB-NIR imagery supported by ground control points and park boundaries collected during field survey. LST at matching resolution was obtained through downscaling of Landsat-8 LST at 30/100m resolution, calculated with the Radiative Transfer Equation (RTE). Landscape metrics for patches of parks were calculated using landscapemetrics R library and related to neighbourhood distances over built-up land use (LU).
Results
Urban parks with homogenous cores and less complex shape provide distinctly higher cooling of neighbouring built-up LU of circa 2.55 °C over the distance of 18 m from park boundaries. Four metrics: contiguity index (CONTIG), core area index (CAI), fractal dimension index (FRAC) and perimeter-area ratio (PARA) represent significant relationship between spatial configuration of parks and their cooling distance. No cooling capacity of parks regardless of their shape and core was observed beyond the distance of 18 m, which remained constant with small fluctuations in the range of 0.5 °C up to the distance of 600 m.
Conclusions
The study concludes that cooling distance of urban parks in their neighbourhood extends up to 18 m, which is shorter than suggested by other studies.Landscape Ecolog
Vision-based autonomous UGV detection, tracking, and following for a UAV
Get PDFThis study proposes a methodology for unmanned ground vehicle (UGV) navigation in off-road environments where GPS signals are not available. The Husky-A200 at Cranfield University, United Kingdom has been used as a UGV in this research project. Due to the limited field of vision of UGVs, a UAV-UGV collaboration approach was adopted. The methodology involves five steps. The first step is divided into three phases: The aerial images of UGV from UAV are generated in the first phase. In the second phase, the UGV is detected and tracked using computer vision techniques. In the third phase, the relative pose (position and heading) between the UAV and UGV is estimated continuously using visual data. In the second step, the UAV maintain a fixed location (position and heading) relative to the UGV. The third step involves capturing aerial images from the UAV‘s mounted camera and transmitting it to the ground station instantly to create a global traversability map that classifies terrain features based on their traversability. In the fourth step, additional sensors such as LiDAR, radar, and IMU are used to refine the global traversability map. In the final step, the UGV navigates automatically using the refined traversability map. This study will focus on the first two steps of the methodology, while subsequent studies will address the remaining steps.AIAA SCITECH 2024 Foru
Investigating the influence of sulphur amendment and temperature on microbial activity in bioremediation of diesel-contaminated soil
Get PDFThis study investigated the effectiveness of incorporating sulphur (S) with nitrogen (N) and phosphorus (P) for enhancing microbial activity in diesel-contaminated soil during ex-situ bioremediation. While N and P amendments are commonly used to stimulate indigenous microorganisms, the potential benefits of adding S have received less attention. The study found that historically contaminated soil with a moderate concentration of total petroleum hydrocarbons (TPH; 1270 mg/kg) did not have nutrient limitation, and incubation temperature was found to be more critical for enhancing microbial activity. However, soil spiked with an additional 5000 mg/kg of diesel showed increased activity following NP and NPS amendment. Interestingly, NPS amendment at 10 °C resulted in higher microbial activity than at 20 °C, indicating the potential for a tailored nutrient amendment approach to optimize bioremediation in cold conditions. Overall, this study suggests that incorporating S with N and P can enhance microbial activity in diesel-contaminated soil during ex-situ bioremediation. Furthermore, the study highlights the importance of considering incubation temperature in designing a nutrient amendment approach for bioremediation, especially in cold conditions. These findings can guide the design and implementation of future effective bioremediation strategies for petroleum hydrocarbon-contaminated soil.The authors thank ERS and the BBSRC NIBB's Environmental Biotechnology Network, (EBNET, grant reference BB/S009795/1) for funding this research project.Heliyo
Generative artificial intelligence in business: towards a strategic human resource management framework
Get PDFAs businesses and society navigate the potentials of generative artificial intelligence (GAI), the integration of these technologies introduces unique challenges and opportunities for human resources, requiring a re-evaluation of human resource management (HRM) frameworks. The existing frameworks may often fall short of capturing the novel attributes, complexities and impacts of GAI on workforce dynamics and organizational operations. This paper proposes a strategic HRM framework, underpinned by the theory of institutional entrepreneurship for sustainable organizations, for integrating GAI within HRM practices to boost operational efficiency, foster innovation and secure a competitive advantage through responsible practices and workforce development. Central to this framework is the alignment with existing business objectives, seizing opportunities, strategic resource assessment and orchestration, re-institutionalization, realignment and embracing a culture of continuous learning and adaptation. This approach provides a detailed roadmap for organizations to navigate successfully the complexities of a GAI-enhanced business environment. Additionally, this paper significantly contributes to the theoretical discourse by bridging the gap between HRM and GAI adoption, the proposed framework accounting for GAI–human capital symbiosis, setting the stage for future research to empirically test its applicability, explore its implications on HRM practices and understand its broader economic and societal consequences through diverse multi-disciplinary and multi-level research methodologies
Method Development for Compression Testing of Synthetic Ballistic Gelatine
Get PDFPoster contribution to the Defence and Security Doctoral Symposium 2023
Assessment of the Conceptual and Moral Factors on the Outcome of Wars: An AI Perspective
Get PDF3MT contribution to the Defence and Security Doctoral Symposium 2023
Performance Characteristics and Permittivity Modelling of a Surface Plasmon Resonance Sensor for Non-destructive Metal Surface Monitoring in a Saline Maritime Environment
Get PDFPoster contribution to the Defence and Security Doctoral Symposium 2023
Enhancing the efficiency of rotary thermal propulsion systems
No full textThis article belongs to the Special Issue: Disruptive Solutions for Innovative Internal Combustion Engines and Advanced CombustionTransport electrification is essential for reducing CO2 emissions, and technologies such as hybrid and range-extended electric vehicles will play a crucial transitional role. Such vehicles employ an internal combustion engine for on-board chemical energy conversion. The Wankel rotary engine should be an excellent candidate for this purpose, offering a high power-to-weight ratio, simplicity, compactness, perfect balance, and low cost. Until recently, however, it has not been in production in the automotive market, due, in part, to relatively low combustion efficiency and high fuel consumption and unburnt hydrocarbon emissions, which can be traced to constraints on flame speed, an elongated combustion chamber, and relatively low compression ratios. This work used large eddy simulations to study the in-chamber flow in a peripherally ported 225cc Wankel rotary engine, providing insight into these limitations. Flow structures created during the intake phase play a key role in turbulence production but the presence of the pinch point inherent to Wankel engine combustion chambers inhibits flame propagation. Two efficiency-enhancement technologies are introduced as disruptive solutions: (i) pre-chamber jet ignition and (ii) a two-stage rotary engine. These concepts overcome the traditional efficiency limitations and show that the Wankel rotary engine design can be further enhanced for its role as a range extender in electrified vehicles.Energie
Exploring transformative and multifunctional potential of MXenes in 2D materials for next-generation technology
Get PDFMXenes, a rapidly growing family of two-dimensional (2D) transition metal carbides, nitrides, or carbonitrides (Mn+1XnTx, where M is a transition metal, X is carbon, nitrogen, or both, and T represents surface functional groups), have captured the scientific community's interest due to their exceptional physicochemical properties and diverse technological applications. This comprehensive review explores the latest breakthroughs in MXene synthesis and characterisation, emphasising their multifaceted applications in energy storage, catalysis, sensing, and other cutting-edge domains. This review examines the most widely used MXene synthesis strategies, including selective etching and delamination, and highlight recent advancements in controlling surface terminations, composition, and morphology. The influence of these synthetic parameters on MXene properties is discussed in detail. Characterisation techniques, ranging from spectroscopic methods to electron microscopy, are essential for elucidating MXenes' structure-property relationships. Research into energy storage leverages MXenes' high electrical conductivity, large surface area, and chemical tunability. This has led to significant progress in the field. This paper presents research efforts focused on optimising MXenes for both battery and supercapacitor applications. Additionally, the catalytic prowess of MXenes, particularly in electrocatalysis and photocatalysis, is explored, emphasising their role in green energy technologies and environmental remediation. MXenes' remarkable sensitivity and selectivity make them promising candidates for sensing various gases, biomolecules, and ions, offering exciting possibilities in healthcare and environmental monitoring. Importantly, this review underscores the need for continued optimisation of MXene synthesis protocols to achieve large-scale production, enhanced stability, and precise control over properties across various fields.Engineering & Physical Sciences Research Council (EPSRC) under grant numbers EP/R016828/1 (Self-tuning Fibre-Reinforced Polymer Adaptive Nanocomposite, STRAIN comp) and EP/R513027/1 (Study of Microstructure of Dielectric Polymer Nanocomposites subjected to Electromagnetic Field for Development of Self-toughening Lightweight Composites).Open Ceramic