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Influence of temperature, sunlight and wind on the mobilization of propylene glycol from airport de‐icers by rainfall
No full textCommercial anti‐icers and de‐icers (CADs) are essential for safe winter operation; yet, their mobilization remains poorly understood, limiting the ability of airport operators to optimize treatment processes, thus presenting a significant risk to freshwater ecosystems. This study investigated the impact of meteorological conditions and durations on CAD mobilization during rainfall. Two common commercial formulations were subjected to a range of controlled meteorological conditions, including temperature (+18°C, +5°C and −5°C), wind and sunlight, over 1 or 2 weeks, followed by simulated rainfall, where glycol in runoff was analysed by HPLC every minute. Exposure to sunlight and wind substantially decreased propylene glycol mobilization (6.9%–45.3% decrease). However, higher temperatures increased runoff concentrations of the anti‐icing fluid (31.6%–36.9% increase). There were significant differences in mobilization rates between commercial products (p < 0.045). Weathering duration had a minimal effect on mobilization. These results offer critical insights for airport operators in contaminant mobilization and treatment.This work was supported by PhD studentship funding to B. Exton fromthe Natural Environment Research Council (NERC, UK) through theCentral England NERC Training Alliance (CENTA) (NE/L002493/1)Cranfield University, through their industry partnership PhD scheme,and Heathrow Airport LtdWater and Environment Journa
Real-time surrogate for quadcopter attitude control: a least-squares quadratic imitation learning approach
No full textImitation Learning (IL) has shown considerable promise in enabling automated systems to replicate expert behavior with reduced computational overhead. However, many IL techniques often suffer from limited interpretability, generalization, and the need for vast quantities of high-quality expert data. This paper presents Least-Squares based Quadratic Imitation Learning (LS-QIL), a simple yet powerful IL framework designed to overcome these limitations through a transparent and analytically tractable policy structure. LS-QIL learns a quadratic control policy using linear least-squares optimization, resulting in a closed-form mapping between system states and control actions that enables efficient and reliable deployment in real-time environments. Leveraging high-performance Nonlinear Model Predictive Control (NMPC) as the expert, LS-QIL captures complex, optimal behavior while significantly reducing online computational demands. The framework is applied to quaternion-based quadrotor attitude control, leveraging its compact and singularity-free representation to ensure robustness and stability. Through extensive simulation and analysis, the imitation learning-based framework demonstrates strong performance, adaptability, and practical feasibility, making it a promising surrogate for real-time control tasks. This research strengthens the foundations of imitation learning by bridging the gap between model-based control and learning-based methods. It offers a stable, scalable, and interpretable solution for real-time applications, highlighting a path toward scalable autonomy in aerial robotics and beyond.This research is supported by Munich Aerospace within the research group "Robust and Efficient Real-Time Flight Path Optimization." A sincere gratitude to Prof. Luis Rodrigues at Concordia University, Canada, for his guidance.AIAA Aviation Forum and Ascend 202
A submersible power station: part B propulsion systems
No full textThis article belongs to the Section Ocean EngineeringNuclear power continues to be a great promise in the green revolution, as it is a cost-effective, low-emission, and safer alternative to fossil fuels that is capable of continuous operation. A preliminary design evaluation is presented for a submersible nuclear power station capable of operating under its own power during emergencies and routine maintenance. Because it is stationed at sea, it offers a resilient solution to natural disasters such as earthquakes and tsunamis, giving it the capability to disengage and sail to deeper waters in less than a half of an hour. In the present evaluation, the hull dimensions of a very large existing submarine and the turbomachinery layout of a Pebble Bed Modular Reactor cycle were used as baselines. The conceptual design of the submersible nuclear power station includes reactor and turbomachinery integration, preliminary sizing (4 pressure hull design; total length of 57.74 m), and propulsion system analysis, demonstrating the technical viability of the proposed submersible power station.Journal of Marine Science and Engineerin
Saudi Arabia’s defence industrial transition: from vision to reality?
No full textThe Kingdom of Saudi Arabia has long harboured defence industrial ambitions, but with minimal practical impact. Efforts have been stymied by overly complex regulation, stuttering institutional commitment and an inchoate defence industrial strategy. Vision 2030 changed all that, driven by a 50% localisation goal by 2030. The Kingdom has the world’s 5th biggest defence budget and is its 3rd biggest arms importer, reflecting huge market leverage to extract defence offset benefits. The road to localisation has been through overseas acquisition, with the desire to succeed emerging from a stronger national identity along with a determination to exploit strategically unbounded capability opportunities.Defence and Peace Economic
Point cloud completion based pose estimation for spacecraft
No full textThe growing density of near-Earth space operations necessitates advanced autonomous Guidance, Navigation, and Control (GNC) systems capable of reliable and precise pose estimation during close-proximity operations (CPO). Existing 3D vision-based localization methods, including traditional algorithms and recent machine learning enhancements, often struggle with noisy, sparse, or incomplete point cloud data, limiting their applicability in safety-critical, non-cooperative scenarios. This paper introduces PCC-KIPE, a novel pose estimation framework that overcomes these limitations by combining 3D point cloud completion with a reward-based search algorithm, eliminating the need for exact point correspondences or covariance matrices required by conventional methods. By reconstructing complete target models from partial observations and performing pose estimation through a robust search strategy, PCC-KIPE demonstrates enhanced resilience to data imperfections and reduced reliance on extensive training datasets. The proposed approach offers a promising direction for scalable, autonomous GNC in increasingly complex space environments.This research was supported by the Inha University funded project Precision Guidance and Navigation for Deep Space Exploration (project number P20962).11th European Conference for AeroSpace Sciences (EUCASS 2025
Data: Proof-of-concept for on-farm green (electrolytic) hydrogen generation and use in England’s agrifood sector: interview transcripts
No full textThis project aims to develop and evidence a practical, replicable proof-of-concept for on-farm green (electrolytic) hydrogen generation and use in England’s agrifood sector, addressing key techno-economic uncertainties at farm and rural-community scales to support net-zero and energy security. Funded by the EPSRC Impact Acceleration Ac
count and co-designed with Cator & Co and agrifood/energy stakeholders, it combines primary interviews with publicly available datasets to evaluate feasibility and deployment pathways.Engineering and Physical Sciences Research Council (EPSRC
Dataset supporting "Natural Dyes and Regenerated Cellulose Fibers Blending using Ionic Liquid as a Common Platform for Sustainable Textiles/Fashion Applications"
No full textConventional textile dyeing generates significant water pollution through synthetic dye leaching, creating urgent need for closed-loop processes. The current work uses a novel in-situ spin dyeing process to develop dyed cellulose fibres, using ionic liquid (IL) as a unified platform to dissolve cellulose and disperse a range of natural dyes – eliminating post-spinning coloration. The spin dyeing method effectively requires less water uptake and is a sustainable benign method for the future textile industry. Different natural dyes were incorporated into the cellulose-IL composite solution to add vibrant colours to the fibres. Natural dyes derived from Sorghum, and Coreopsis show better conjugation with the wet-spun fibres, while the other dyes do not show similar levels of dye stability and incorporation within the fibres. FTIR results confirmed chemical bonding of dyes in the fibres. SEM images indicated the homogeneous dispersion of dye across the fibres. The resultant dyed fibres demonstrate similar mechanical properties in comparison to the neat cellulosic fibres, and commercially available fibres. Although thermal stability decreased for the dyed fibres, mechanical performance validates IL-mediated spin-dyeing as a viable alternative to petroleum-based dyes. This first demonstration of ILs enabling integrated fibre production and natural dyeing establishes a blueprint for sustainable textiles manufacturing.Engineering and Physical Sciences Research Council (EPSRC
An NB-IoT payload for space communications and navigation
No full textThis paper presents a payload design for a Narrowband Internet of Things (NB-IoT) based communication and navigational system. The main objective of this design is to enable the integration of NB-IoT in a constellation of satellites. NB-IoT technology is attracting considerable attention in satellite communications because it has the potential to support reliable, wide-area, and low-power connectivity for critical applications such as telemetry, command and control, and safety messaging. Its versatility makes NB-IoT particularly well-suited to both conventional aviation and the expanding Unmanned Aerial Vehicle (UAV) sector. Drawing on these use cases, this paper identifies the key requirements and uses them to inform the payload design. The payload leverages Software-Defined Radio (SDR) technology for operational flexibility, addressing spectrum allocation, RF interference, and Doppler shift challenges. The design uses a phased-array antenna design of 10 by 10 circular patch elements optimised for space-based NB-IoT transmissions in the S-band frequency. This allows for electronic steering of its beam, minimising the overall payload mass and complexity while increasing its footprint and ensuring connectivity within a 40-degree half-cone angle. Navigation signal processing is achieved by leveraging the Doppler shifting of the communication signal, providing a velocity-based location. To provide a reliable communications link, the system also incorporates error correction techniques in a protocol designed and implemented to compensate for the Doppler shift in the signal. To validate the results of the design, a technology demonstrator using an SDR as well as custom Electrical Power System (EPS) and On-Board Data Handling (OBDH) boards are presented. These results demonstrate that successful connectivity and data transmission are feasible in a simulated environment, paving the way for future satellite-to-UAV communication using NB-IoT protocols. This payload system will contribute to the advancement of satellite-based NB-IoT networks, offering new possibilities for autonomous aerial operations. Future work could focus on optimising power efficiency and conducting real-world flight tests to validate system performance and reliability further.IAF Space Communications and Navigation Symposium, Held at the 76th International Astronautical Congress (IAC 2025
Understanding HRM financial value from obtaining more star performers: introduction on a paper and commentary collection
Get PDFJoo, Aguinis, Lee, Kremer and Villamor demonstrated in their article entitled HRM’s financial value from obtaining more star performers in the International Journal of Human Resource Management (HRM) the financial value of acquiring star performers by using utility analysis on 206 samples of individual performance encompassing 824,924 workers. The analyses showed that HRM adds greater financial value by obtaining more star performers. Four (teams of) scholars, Michael Sturman, Xueging Fan, and Hanbo Shim, Michal Biron, Carol Kulik, and Mark Huselid responded to an invitation to comment on this article. In this introduction of the first commentary collection, we provide short summaries of the Joo et al. article and the four commentaries and discuss future research
Monitoring of stress corrosion cracking under representative pipeline conditions.
Get PDFMori, Stefano - Associate SupervisorPipelines are subjected to various stresses during operation, which are induced
from factors including fluid flow, ocean currents, mechanical vibrations, or earth
movements. These stresses, in combination with the corrosive environment can
cause an increase in pipeline’s corrosion rate and, subsequently, lead to stress
corrosion cracking. The presence of trace gases (CO₂, O₂, H₂S), is expected to
have an influence on this susceptibility. As such, the aim of the research is to
access the impact of trace gases linked to CO₂transportation, carbon capture
and storage, enhanced oil recovery and other pipeline operations. This is key to
understanding whether pipelines are at increased risk of failure.
In this research, the stress corrosion behaviour of API 5L X65, X70, X80 and
X100 has been investigated. Tests were conducted in 3.5 % NaCl solution with
either N₂, CO₂, or mixtures of O₂/N₂ and O₂/CO₂ bubbled through. Liquid
temperatures were maintained at either at 5 ˚C, 15 ˚C or 25 ˚C. C-ring and 3-point
bending specimens were stressed at 80 % or 95 % of yield strength. Linear
polarization resistance monitored corrosion rates. Corrosion extent and
morphology were examined by optical microscopy (to measure metal loss),
followed by scanning electron microscopy analysis.
The results from baseline experiment (N₂) showed correlations between
corrosion rates and both stress and temperature. All samples exposed with mixed
O₂/N₂ presented higher corrosion rates by 1 order of magnitude. Their damage
morphology consisted of metal loss and pits features. These pits had deeper,
elliptical morphology in comparison with N₂-only data. Results from the pure CO₂
gas showed more rapid corrosion rates than in pure N₂ and mixed O₂/N₂.
However, with change in trace gas mixture from pure CO₂ to O₂/CO₂, a large
increase in corrosion rates of about 70% was observed. Similar morphologies
were observed on X65, X70 and X80 samples in solution with pure CO₂ and
mixed O₂/CO₂ at all solution temperatures, with a deep undercutting morphology
and discontinuous microcracks being observed. In contrast, X100 showed wide,
deep ellipse-shaped pits.PhD in Energy and Powe