20505 research outputs found
Sort by
Environmental impacts of low and high order detonations in water
Get PDFThe clearance of dumped munitions often relies on low order (LO) and high order (HO) detonation techniques, both of which pose significant risks to aquatic ecosystems. LO detonation leaves behind substantial explosive residues, whereas HO detonation generates intense shock waves and extensive fragmentation. This study examines the environmental impact of these detonation methods, including partial detonation, under semi-controlled conditions using six 1000-litre Intermediate Bulk Container (IBC) tanks. Partial detonation represents an incomplete LO detonation, resulting in the high transfer of TNT to the aquatic environment. Explosive residues were almost 8 times higher after LO detonations (8.7 ± 2.8 mg/L) compared to HO (1.2 ± 0.4 mg/L). Fragmentation analysis revealed that HO produced more than twice the number of fragments compared to LO, increasing the potential for physical damage. By integrating these findings with modelling, the fragment stopping distances were estimated. The maximum distance covered by the fragments ranged between 94.9 and 107.1 m. The acute toxicity spatial extent of explosive contamination from a single World War (WW) munition detonation was found to be 25–40 m (LO); 36–58 m (Partial); 14–23 m (HO). Considering, there are stockpiles of munitions in the water bodies, this distance can be much larger. These insights aid to minimise both chemical and physical environmental impacts, particularly in the context of World War-era munitions clearance.Special thanks to UK Ministry of Defence and DNV for sponsoring the research work.Journal of Hazardous Material
Integrating causal analysis based on system theory with network modelling to enhance accident analysis
Get PDFThis study integrates Causal Analysis based on System Theory (CAST) with network modelling to enhance accident analysis in aviation ground handling. Using 117 Passenger Boarding Steps (PBS)-related incident reports, the CAST analysis identified 74 flaws across 40 control actions, leading to four loss types. Approaching, inspecting, adjusting, and repositioning PBS were the most critical control actions contributing to incidents. Key contributory factors included issues around training, workload management, situational awareness, performance management, recruitment, organisational culture, procedures, equipment maintenance, and financial constraints. The integration of network modelling into CAST enhanced accident analysis by visualising complex interactions, offering deeper insights into accident causation and identifying critical nodes. This study demonstrates that combining CAST with network modelling enhances the understanding of accidents and safety risks, supporting evidence-based decision-making for aviation safety professionals and improving ground handling risk management strategies.
Practitioner Summary:
This study integrates CAST with network modelling to enhance accident analysis in aviation ground handling. Analysing 117 passenger boarding steps incidents, the study identifies critical control actions and contributory factors. Network modelling enhances CAST by revealing complex interactions, providing deeper insights into incidents, and supporting improved risk management strategies.Ergonomic
Development of impact characteristics response model for combined tube expansion axial splitting module
Get PDFCombined tube-expansion and axial splitting mechanism yields excellent force-displacement characteristic and high stroke efficiency. In this paper, a mathematical model to estimate and optimise impact response of such mechanism was developed, to correlate the impact response to the module dimensional parameters, i.e. diameter-to-thickness ratio, D1/t and expansion ratio, D2/D1 and other design parameters such as material strength, expansion angle, and friction coefficient. Accurate finite element (FE) analysis, validated with experimental results were performed to generate results sufficient to form a response surface model (RSM). The current mathematical model successfully captured the effect of expansion ratio, thickness ratio, and initial diameter of the tube, with R2 of 0.99 for specific energy absorbed and 0.81 for mean crushing force throughout 80 data points. A case study was also presented which shows the result comparison between numerical and the proposed model, yielding error below 1% difference for mean and peak crushing force, total energy absorbed, specific energy absorbed (SEA), stroke and crushing force efficiencies. The model has also been implemented in an optimisation for railway vehicle case study using the proposed mathematical model. The current research found that the combined module could reach SEA and stroke efficiency values of 29.74 kJ/kg and 0.99, respectively, significantly better than most of the metallic-based impact energy absorbing mechanisms.The research is partially funded and supported by ITB through Research, Community Service, and Innovation funding scheme and the Faculty of Mechanical and Aerospace Engineering ITB for the testing facility, for which the authors express their gratitude.International Journal of Crashworthines
Energy harvesting technologies on high-speed railway infrastructure: review and comparative analysis of the potential and practicality
Get PDFA comprehensive quantitative analysis is provided of the potential applications of energy harvesting (EH) technologies tailored to high-speed railway infrastructure. The study compares the various energy sources within railway infrastructure and identifies suitable EH technologies. Feasible designs and scales of EH are assessed based on the installation location; the overall power availability and energy yield are compared for a notional high-speed railway. For resonant EH devices an assessment is also given of the optimal tuning frequency. Vibration-based EH, when applied to the track or bridge structures, can provide sufficient power for individual low-power sensors; however, its output is insufficient for higher-power applications or for data transmission unless energy storage devices are incorporated. Despite the elevated noise levels generated by high-speed trains, the energy available from this acoustic source is negligible and impractical for EH. Small vertical axis wind turbines installed close to the track and driven by passing trains show great potential, capable of harvesting several orders of magnitude more energy than vibration-based EH. Solar photovoltaic panels can generate significantly more energy than other methods, although their output is confined to daylight conditions and is contingent upon weather conditions.Engineering and Physical Sciences Research CouncilThis study formed part of a project that was initiated and funded by HS2 Ltd through the framework of UKCRIC (UK Collaboratorium for Research on Infrastructure and Cities) which was initially funded under EPSRC, United Kingdom, grant EP/R017727/1.Sustainable Energy Technologies and Assessment
Integrating explainable AI into two-tier ML models for trustworthy aircraft landing gear fault diagnosis
Get PDFCorrection Notice:
Title of the research is changed from “Comprehensive Exploration and Development of Explainable AI for Robust Aircraft Landing Gear Fault Diagnosis” to “Integrating Explainable AI into Two-Tier ML Models for Trustworthy Aircraft Landing Gear Fault Diagnosis”, because the present research paper is more research oriented than the just exploration as submitted during abstract submission.
Authors list is updated, Antonios Tsourdos name is included.
And Figure 1 has to replaced with this HD images [sic], the one in the published paper is of very low quality.As the aviation industry increasingly relies on data-driven intelligence to enhance safety and operational efficiency, the demand for AI solutions that are both technically robust and readily interpretable continues to intensify. This research presents a pioneering methodology for advanced fault diagnosis in aircraft landing gear systems that not only achieves high predictive accuracy but also provides transparent, actionable insights. Building upon a twotier machine learning framework—integrating fault classification with intelligent sensor data imputation—we demonstrate how state-of-the-art explainability techniques, notably LIME and SHAP, can elucidate the underlying logic of complex models. By exposing the critical features and sensor parameters driving each decision, this approach empowers maintenance engineers and operations personnel to understand, validate, and trust the model’s outputs rather than relying on opaque “black-box” predictions.
Our results indicate that interpretable fault diagnoses facilitate more confident decisionmaking, streamline maintenance interventions, and reduce the likelihood of unforeseen component failures. Beyond mere compliance with emerging regulatory standards for AI transparency, this method establishes a blueprint for deploying machine learning solutions that are not only accurate and robust, but also inherently comprehensible. In an era where aerospace systems must seamlessly integrate precision, reliability, and human oversight, our work sets a precedent for creating intelligent tools that foster trust, enhance collaboration between technical experts and AI models, and ultimately contribute to safer and more efficient aviation operations.AIAA SCITECH 2025 Foru
EcoYield-SAFE: The biophysical model underpinning research article "Predicted yield and soil organic carbon changes in agroforestry, woodland, grassland and arable systems under climate change in a cool temperate Atlantic climate"
No full textEuropean Commission through the AGROMIX (AGROforestry and MIXed farming systems; grant agreement 862993).This version of EcoYield-SAFE model was developed from the Yield-SAFE model developed on the EU SAFE project (Silvoarable Agroforestry for Europe). The original equations are described in a paper by van der Werf et al. (2007).
EcoYield-SAFE was previously enhanced so that crop water use responds to the daily vapour pressure deficit that is dependent on the change of temperature and wind speed, promoted by the trees. Soil carbon has also been included in the EcoYield-SAFE model. This is based on the RothC model (Rothamsted soil carbon; Coleman and Jenkinson (2014)) and predicts soil carbon changes under different land uses and over time. These changes were undertaken during the EU AGFORWARD project (Grant number 613520). More recently, to determine the effect of climate change on tree and crop yields, EcoYield-SAFE v2 has been further developed to include the effect of increases in atmospheric carbon dioxide on the radiation use efficiency of the trees, grass, and crops. These changes were undertaken during the EU AGROMIX project (Grant agreement 862993).
More recently, to determine the effect of climate change on tree and crop yields, EcoYield-SAFE has been further developed to include the effect of increases in atmospheric carbon dioxide (CO2) on the radiation use efficiency of the trees, grass, and crops. These changes were undertaken during the EU AGROMIX project.
A previous and simpler version of the model, named Yield-SAFE v2 is also available online (Burgess et al., 2023) in Cranfield University's CORD repository (https://dspace.lib.cranfield.ac.uk/handle/1826/22344)
Assessment of hydrogen storage and pipelines for hydrogen farm
Get PDFThis paper presents a thorough initial evaluation of hydrogen gaseous storage and pipeline infrastructure, emphasizing health and safety protocols as well as capacity considerations pertinent to industrial applications. As hydrogen increasingly establishes itself as a vital energy vector within the transition towards low-carbon energy systems, the formulation of effective storage and transportation solutions becomes imperative. The investigation delves into the applications and technologies associated with hydrogen storage, specifically concentrating on compressed hydrogen gas storage, elucidating the principles underlying hydrogen compression and the diverse categories of hydrogen storage tanks, including pressure vessels specifically designed for gaseous hydrogen containment. Critical factors concerning hydrogen gas pipelines are scrutinized, accompanied by a review of appropriate compression apparatus, types of compressors, and particular pipeline specifications necessary for the transport of both hydrogen and oxygen generated by electrolysers. The significance of health and safety in hydrogen systems is underscored due to the flammable nature and high diffusivity of hydrogen. This paper defines the recommended health and safety protocols for hydrogen storage and pipeline operations, alongside exemplary practices for the effective implementation of these protocols across various storage and pipeline configurations. Moreover, it investigates the function of oxygen transport pipelines and the applications of oxygen produced from electrolysers, considering the interconnected safety standards governing hydrogen and oxygen infrastructure. The conclusions drawn from this study facilitate the advancement of secure and efficient hydrogen storage and pipeline systems, thereby furthering the overarching aim of scalable hydrogen energy deployment within both energy and industrial sectors.Energie
Temperature-dependent electrosynthesis of PEDOT:PSS: enhanced Na+ transfer targeting high-performance Na-ion batteries
Get PDFPoly(3,4-ethylenedioxythiophene):Poly(sodium 4-styrenesulfonate) (PEDOT:PSS) is a versatile conducting polymer with physicochemical properties favourable for energy storage applications, such as chemical and mechanic stability and flexibility. However, the temperature at which the polymer is synthesised can significantly influence its properties. In this study, a detailed investigation of the effect of temperature on the electroactivity, morphology, optical properties, and ionic/solvent transport during the redox conversion of potentiostatically and galvanostatically synthesised films was conducted. Electrochemical data, supported by ellipsometry, atomic force microscopy, microgravimetry, and probe beam deflection measurements, revealed that films synthesised at lower temperatures (0 °C) were more compact compared to those synthesised at higher temperatures (40 °C). Films synthesised at 0 °C also exhibited near-ideal reversibility, with a QO/QR ratio of ca. 1. Importantly, the 0 °C films showed a strong pseudocationic doping behaviour, characterised by predominant sodium ion exchange during redox processes. In contrast, films synthesised at 40 °C exhibited mixed ion participation (both sodium and perchlorate), which could negatively impact the performance of electrode material in battery applications. This study demonstrates the potential of PEDOT:PSS as a versatile material for sodium ion cathodes, with properties that can be finely tuned through the synthesis temperature, yielding more compact ion-storage films at lower temperatures.French National Centre for Scientific Research, Fundação para a Ciência e TecnologiaThis work was funded by the Portuguese Fundação para a Ciência e a Tecnologia (FCT) I.P./MCTES through projects UIDB/00100/2020 and UIDP/00100/2020– Centro de Química Estrutural.Electrochimica Act
Recovery from startle and surprise: a survey of airline pilots' operational experience using a startle and surprise management method
Get PDFA significant safety challenge airline pilots contend with is the possibility of experiencing startle and surprise. These are cognitive-emotional responses that may temporarily impair performance and that have contributed to multiple fatal loss of control events. Several self-management methods exist that are intended to facilitate recovery from startle and surprise, but these have only been tested in simulator experiments. The current study addresses this research gap by surveying the perceptions of 239 airline pilots on the utility and benefit of a method which they use in operational practice– the “Reset Method”. Overall, the survey results revealed that pilots felt the method improved mental preparedness, and reduced stress. A reported reason for not applying the method was the urge to act quickly. In addition, not all steps of the method were applied equally, and some pilots found the method difficult to fit into the existing procedures of several time-critical scenarios (e.g., aircraft upsets and emergency landings). We recommend training self-management methods in scenarios which carry the most risk of negative effects of startle and surprise. We also recommend instilling awareness of the ‘startle paradox': self-management techniques are most difficult to apply in situations where they are most beneficial. Method shortening and simplification may facilitate application. Future research should focus on refining the method's implementation, addressing the startle paradox, and understanding the transferability of startle and surprise management methods to other safety critical industries defined by complex sociotechnical interactions.International Journal of Industrial Ergonomic
Novel hybrid prognostics of aircraft systems
Get PDFThis article belongs to the Special Issue Fault Detection Technology Based on Deep LearningAccurate forecasting of the remaining useful life (RUL) of aviation equipment is crucial for enhancing safety and reducing maintenance costs. This study presents a novel hybrid prognostic methodology that integrates physics-based and data-driven models to improve RUL estimations for critical aircraft components. The physics-based approach simulates long-term degradation patterns using fundamental principles such as mass conservation and Bernoulli’s equation, while the data-driven model employs a hyper tangent boosted neural network (HTBNN) to detect short-term anomalies and deviations in real-time sensor data. The integration of various models enhances accuracy, adaptability, and reliability in prognostics. The proposed methodology is assessed using NASA’s N-CMAPSS dataset for gas turbines and a fuel system test rig, demonstrating a 15% improvement in prediction accuracy and a 20% reduction in uncertainty compared to traditional methods. These findings highlight the potential for widespread application of this hybrid methodology in predictive maintenance and prognostic and health management (PHM) of aircraft systems.This research has received funding from the European Commission under the Marie Skłodowska Curie program through the H2020 ETN MOIRA project (GA 955681).Electronic