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Two-stage violence detection using ViTPose and classification models at smart airports
Get PDFThis study introduces an innovative violence detection framework tailored to the unique requirements of smart airports, where prompt responses to violent situations are crucial. The proposed framework harnesses the power of ViTPose for human pose estimation and employs a CNN-BiLSTM network to analyse spatial and temporal information within keypoints sequences, enabling the accurate classification of violent behaviour in real-time. Seamlessly integrated within the SAAB’s SAFE (Situational Awareness for Enhanced Security) framework, the solution underwent integrated testing to ensure robust performance in real-world scenarios. The AIRTLab dataset, characterized by its high video quality and relevance to surveillance scenarios, is utilized in this study to enhance the model's accuracy and mitigate false positives. As airports face increased foot traffic in the post-pandemic era, the implementation of AI-driven violence detection systems, such as the one proposed, is paramount for improving security, expediting response times, and promoting data-informed decision-making. The implementation of this framework not only diminishes the probability of violent events but also assists surveillance teams in effectively addressing potential threats, ultimately fostering a more secure and protected aviation sector. Codes are available at: https://github.com/Asami-1/GDP.2023 IEEE Smart World Congress (SWC
An evaluation of large diameter through-thickness metallic pins in composites
Get PDFThere is increasing demand for functional through-thickness reinforcement (TTR) in composites using elements whose geometry exceeds limitations of existing TTR methods like tufting, stitching, and z-pinning. Recently, static insertion of large diameter TTR pins into heated prepreg stacks has proven a feasible and robust reinforcement process capable of providing accurate TTR element placement with low insertion forces and lower tow damage compared with existing methods for similar element sizes (>1mm diameter) like post-cure drilling. Local mechanical performance and failure mechanics of these pinned laminates are reported here. Laminates with a single statically inserted pins (1.2, 1.5, and 2.0 mm) can mostly retain their in-plane integrity alongside a local improvement in mode I delamination toughness in carbon fibre-benzoxazine laminates. Tensile strength is mostly unaffected by the pins resulting from delamination suppression, whereas there is up to a doubling of Young’s modulus. Compressive strength is significantly diminished (up to 42 %) in pinned laminates. Interlaminar toughness is improved, and peak toughness is pushed ahead of the crack as pin diameter increases. The lack of significant deterioration in in-plane tensile properties in pinned laminates produced using static insertion can expand the range and forms of materials that can be inserted compared to existing TTR.This work was supported by the SEER project which has received funding from the European Union's Horizon 2020 research and innovation programme (Grant agreement 871875).Composite Structure
An incremental approach for calculating dominance-based rough set dependency
Get PDFFeature selection and classification are widely used in machine learning in the context of big data. In many data sets, both attributes and decision classes can be preference ordered. Therefore, to process the data and information based on preference-ordered attributes, dominance-based rough set approach (DRSA) has been proposed. DRSA considers dominance relation between objects and can process the information with preference-ordered attribute domains. The it should be noted that the majority of the algorithms based on DRSA use dependency as an underlying criterion measure for different tasks. However, calculating dependency using the conventional DRSA approach requires the calculation of lower and upper approximations which is a computationally expensive task. A new approach has been proposed in this paper which calculates the dominance-based rough set dependency measure without calculating the lower and upper approximations. The proposed methodology is called the “Incremental Dominance-based Dependency Calculation Method” (IDDC). To justify the proposed approach, both IDDC and conventional approaches are compared using various data sets from the UCI data set repository. Results have shown that the proposed approach outperforms the conventional approach by depicting on average 46% and 98% decrease in execution time and required runtime memory, respectively.Soft Computin
Spacecraft formation keeping and reconfiguration using optimal visual servoing
Get PDFThis paper proposes a direct visual servoing system for spacecraft guidance in formation flying scenarios. The proposed image-based visual servoing system uses image information for planning and executing formation acquisition, reconfiguration, and maintenance maneuvers. The system assumes that LEDs are located at specific points on the satellites, enabling the visual servoing controller to rely on continuous tracking of these features in the camera’s image plane. Analytical developments demonstrate that the proposed optimal visual control system is stable and optimal, and it acts on both the orbital and attitude dynamics of the spacecraft, considering circular and elliptical reference orbits. The distributed image-based controller defines a cost function that minimizes control efforts, and the paper proses an optimal framework for developing controllers that address the issue. A ROS-based simulation tool was used to test the proposed visual servoing controller in a realistic small-sat formation flying scenario. Results indicate that the proposed distributed control strategy is viable and robust against environmental perturbations and disturbances in sensing and actuation.This research was supported by the grant CIAICO/2022/077 “Plataforma de control y simulación de código abierto para escenarios de robótica de servicio en órbita” (Programa AICO 2023, Conselleria de Innovación, Universidades, Ciencia y Sociedad Digital de la Generalitat Valenciana, Spain).The Journal of the Astronautical Science
Undesirable river biofilms: the composition, environmental drivers, and occurrence of sewage fungus
Get PDFSewage fungus is a classic bioindicator of organic pollution in streams and rivers. However, it has received limited scientific interest in recent decades, despite persistent occurrence in lotic ecosystems. The aim of this review is to provide an up-to-date assessment of sewage fungus, its composition and structure, and the environmental factors that influence its growth to support future research and mitigation interventions. We advocate for the term “undesirable river biofilm” (URB) to more accurately characterise the composition, location, and environmental consequences of sewage fungus. These filamentous or gelatinous growths found on the banks and beds of flowing watercourses are composed predominantly of bacteria, not fungi. Based on modern genomic analyses, we now know that URBs are composed of a diversity of microbial taxa, including those that have long been associated with sewage fungus (e.g. Sphaerotilus, Beggiatoa, and Zoogloea) and newer associated taxa (e.g. Rhodoferax and Thiothrix). While organic pollution is generally considered the main trigger, this review highlights the importance of other environmental factors, such as water velocity, river substrate, pollutant composition and loading, and shading, in the occurrence and persistence of URBs. To illustrate the widespread and continued presence of URBs in rivers, environmental surveillance data for England's rivers were analysed. Between 2000 and 2020, environment officers documented 6,025 occurrences of URBs as part of a wider water quality incident reporting programme. Thus, URBs persist even in countries with stringent water quality standards and comprehensive wastewater infrastructure, suggesting they may continue to be a significant issue globally, despite limited public or scientific focus. We argue that in addition to tackling point discharge of organic pollutants, greater emphasis should be placed on understanding the impact of intermittent and diffuse pollution and altered environmental conditions on river ecosystems. To safeguard river ecosystems, a holistic approach is needed that considers pollution in combination with wider river functioning (e.g. river hydrology, geomorphology, biogeochemical processing, and riparian zones) and climate change. Future areas for study into the URB phenomenon are suggested, including more comprehensive monitoring of URBs specifically and river biofilm health generally.NERC through the Central England NERC Training Alliance (CENTA) (NE/L002493/1), Cranfield University through their industry partnership PhD scheme, and Heathrow Airport Ltd.Ecological Indicator
Wear-resistant nickel-matrix composite coatings incorporating hard chromium carbide particles
Get PDFThis work evaluates the influence of plating variables on the morphology, composition homogeneity, and abrasive wear resistance of metal matrix composite coatings. A set of Ni/Cr3C2 coatings were brush plated onto steel coupons modifying two key variables: particle size and brush material. Compositional maps of unprecedented detail have been produced and analysed statistically to enhance understanding of composition distribution. The use of Abbott-Firestone curves to analyse surface morphology enabled the evaluation of valley and peak features. The coating differences highlighted by previous analyses have been compared with their behaviour in abrasive environments, simulated using Taber testing. Moreover, coupling Taber testing with partial compositional maps at different wear stages enabled monitoring of coating wear evolution. This methodology has revealed the importance of particle sedimentation during plating, which increased particle incorporation in the composite coating but also increased composition heterogeneity. The smaller 1.7 μm carbides and abrasive brushes produced coatings with more homogeneous morphologies, higher particle content, and increased resistance against abrasive wear, with a 60% reduction in material loss in comparison to the standard nickel coatings.Frontiers in Coatings, Dyes and Interface Engineerin
Tube and wing aircraft design analysis: data
No full textThis dataset is generated using GENUS for the conference paper "Airliner conceptual designs for the application of alternative fuels" and an upcoming journal pape
Towards global explainability of artificial intelligence agent tactics in close air combat
Get PDFIn this paper, we explore the development of an explainability system for air combat agents trained with reinforcement learning, thus addressing a crucial need in the dynamic and complex realm of air combat. The safety-critical nature of air combat demands not only improved performance but also a deep understanding of artificial intelligence (AI) decision-making processes. Although AI has been applied significantly to air combat, a gap remains in comprehensively explaining an AI agent’s decisions, which is essential for their effective integration and for fostering trust in their actions. Our research involves the creation of an explainability system tailored for agents trained in an air combat environment. Using reinforcement learning, combined with a reward decomposition approach, the system clarifies the agent’s decision making in various tactical situations. This transparency allows for a nuanced understanding of the agent’s behavior, thereby uncovering their strategic preferences and operational patterns. The findings reveal that our system effectively identifies the strengths and weaknesses of an agent’s tactics in different air combat scenarios. This knowledge is essential for debugging and refining the agent’s performance and to ensure that AI agents operate optimally within their intended contexts. The insights gained from our study highlight the crucial role of explainability in improving the integration of AI technologies within air combat systems, thus facilitating more informed tactical decisions and potential advancements in air combat strategies.Aerospac
Synthesis and characterization of chicken feather derived rachis fiber-bamboo particulate hybrid reinforced epoxy composites for sustainable structural applications
Get PDFThis paper aims to reduce waste management and generate wealth by investigating the novelty of combining chicken feather fiber and bamboo particles to produce hybrid biocomposites. This is part of responsible production and sustainability techniques for sustainable development goals. This study aims to broaden animal and plant fiber utilization in the sustainable production of epoxy resins for engineering applications.
Design/methodology/approach
This research used two reinforcing materials [chicken feather fiber (CFF) and bamboo particles (BP)] to reinforce epoxy resin. The BPs were kept constant at 6 Wt.%, while the CFF was varied within 3–15 Wt.% in the composites to make CFF-BP polymer-reinforced composite (CFF-BP PRC). The mechanical experiment showed a 21% reduction in densities, making the CFF-BP PRC an excellent choice for lightweight applications.
Findings
It was discovered that fabricated composites with 10 mm CFF length had improved properties compared with the 15 mm CFF length and pristine samples, which confirmed that short fibers are better at enhancing randomly dispersed fibers in the epoxy matrix. However, the ballistic properties of both samples matched. There is a 40% increase in tensile strength and a 54% increase in flexural strength of the CFF-BP PRC compared to the pristine sample.
Originality/value
According to the literature review, to the best of the authors’ knowledge, this is a novel study of chicken fiber and bamboo particles in reinforcing epoxy composite.Journal of Responsible Production and Consumptio
Greening the future: identifying and mitigating environmental hotspots in the MSME sector - a wall mixer case study
Get PDFIn response to concerns about depleting natural resources, organisations are developing eco-friendly products and services. This study examines the role of manufacturing industries and services in sustainable resource utilisation, focusing on the Micro, Small, Medium Enterprises (MSME) sector, a significant contributor to global Gross Domestic Product (GDP). Using Life Cycle Assessment (LCA) methodology, the research identifies hotspots within the production processes of three companies manufacturing bathroom fittings, specifically the ‘Wall mixer’ component used in households and hotels. The study calculates In response to concerns about depleting natural resources, organisations are developing eco-friendly products and services. This study examines the role of manufacturing industries and services in sustainable resource utilisation, focusing on the MSME sector, a significant contributor to global GDP. Using Life Cycle Assessment (LCA) methodology, the research identifies hotspots within the production processes of three companies manufacturing bathroom fittings, specifically the ‘Wall mixer’ component used in households and hotels. The study calculates CO2 equivalents for each phase of the product lifecycle, identifying average gate-to-gate process values across the companies. This comparison reveals specific hotspots, with a significant one identified, leading to recommendations for industries to prioritise this issue for immediate energy savings. The primary focus is to establish an initial benchmarking system to reduce CO2 equivalents in cradle-to-gate or gate-to-gate systems. Implementing these measures is expected to reduce the carbon footprint, energy consumption, and raw material usage, ultimately enhancing profitability for the three companies. equivalents for each phase of the product lifecycle, identifying average gate-to-gate process values across the companies. This comparison reveals specific hotspots, with a significant one identified, leading to recommendations for industries to prioritise this issue for immediate energy savings. The primary focus is to establish an initial benchmarking system to reduce CO2 equivalents in cradle-to-gate or gate-to-gate systems. Implementing these measures is expected to reduce the carbon footprint, energy consumption, and raw material usage, ultimately enhancing profitability for the three companies.International Journal of Sustainable Engineerin