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Advanced UAV design optimization through deep learning-based surrogate models
Get PDFThe conceptual design of unmanned aerial vehicles (UAVs) presents significant multidisciplinary challenges requiring the optimization of aerodynamic and structural performance, stealth, and propulsion efficiency. This work addresses these challenges by integrating deep neural networks with a multiobjective genetic algorithm to optimize UAV configurations. The proposed framework enables a comprehensive evaluation of design alternatives by estimating key performance metrics required for different operational requirements. The design process resulted in a significant improvement in computational time over traditional methods by more than three orders of magnitude. The findings illustrate the framework’s capability to optimize UAV designs for a variety of mission scenarios, including specialized tasks such as intelligence, surveillance, and reconnaissance (ISR), combat air patrol (CAP), and Suppression of Enemy Air Defenses (SEAD). This flexibility and adaptability was demonstrated through a case study, showcasing the method’s effectiveness in tailoring UAV configurations to meet specific operational requirements while balancing trade-offs between aerodynamic efficiency, stealth, and structural weight. Additionally, these results underscore the transformative impact of integrating AI into the early stages of the design process, facilitating rapid prototyping and innovation in aerospace engineering. Consequently, the current work demonstrates the potential of AI-driven optimization to revolutionize UAV design by providing a robust and effective tool for solving complex engineering problems.Engineering and Physical Sciences Research Council and BAE SystemsAerospac
Does privacy awareness matter? A study of voice assistant-related privacy and security concerns
Get PDFInternet of Things (IoT) and voice assistant (VA) devices and services have become part of our lives. Probably the COVID-19 pandemic accelerated the rate of adoption and diffusion of these technologies as individuals had to adjust their lives and create new ways of working. However, despite their enormous utility, e.g. in entertainment, home security, care homes, supply chain, and logistics, they pose security and privacy threats. Thus, users are expected to exhibit behaviours that protect their privacy and ensure their security. However, there exists a privacy paradox, i.e. users’ security and privacy concerns do not reflect in their use and privacy protection behaviours. To contribute to this discussion, this research sets out to investigate the antecedents of concerns. Understanding what creates concerns in users may provide a clue to the privacy paradox. Drawing on the literature, a parsimonious model that relates knowledge, awareness, attitude, and concerns was tested using data from 123 participants. The results show that indeed knowledge leads to awareness but neither awareness nor knowledge engenders concerns in users. Attitude on the other hand is directly related to concerns. These results highlight the complexity and nebulous nature of the virtual world and call for a relook at knowledge and awareness creation programmes and the extension of policies and device-level security to augment the behaviours of users. Other implications for theory, policy, and practice are discussed.AI Applications in Cyber Security and Communication NetworksLecture Notes in Networks and System
Returnee entrepreneurship in China: the multi-faced story in the travel of location, time and culture
Get PDFWith experience, knowledge and skills accumulated in both home and host countries, returnee entrepreneurs have been recognised as the international knowledge brokers and make significant contributions to the countries’ social-economic development. Particularly, China has emerged as an important context for its high number of global mobility of citizens, the rapid development of the economy, various policies initiatives designed to attract returnees, and the national effort in high-tech industries (Gruenhagen et al., Foundations and Trends in Entrepreneurship 16:310–392, 2020). With China’s rapid economic growth and accelerated global integration, there is a shifting perspective and reality of entrepreneurs returning from overseas. They face various challenges rising from their physical travel of locations, experiencing and adjusting to multi-cultures, as well as changes brought by time moving forward. This chapter discusses the changing nature and current challenges and opportunities
A ROS-based simulation and control framework for in-orbit multi-arm robot assembly operations
Get PDFThis paper develops a simulation and control framework for a multi-arm robot performing in-orbit assembly. The framework considers the robot locomotion on the assembled structure, the assembly planning, and multi-arm control. An inchworm motion is mimicked using a sequential docking approach to achieve locomotion. An RRT* based approach is implemented to complete the sequential assembly as well as the locomotion of MARIO across the structure. A semi-centralised controller model is used to control the robotic arms for these operations. The architecture uses MoveIt! libraries, Gazebo simulator and Python to simulate the desired locomotion and assembly tasks. The simulation results validate the viability of the developed framework.ASTRA 2023: 17th Symposium on Advanced Space Technologies in Robotics and Automatio
Responding to a corruption crisis through disclosure and remedial action: the case of Petrobras
Get PDFThis case study adopts a positivist perspective to examine how Petroleo Brasileiro S.A (“Petrobras”), a high-profile company in its native Brazil with multiple listings including in Brazil and the US, responded to a major corruption scandal arising in 2014. We consider Petrobras's response both in terms of its visible activities – i.e. in relation to anti-corruption and compliance (“ACC”) disclosures in its annual report (AR) and sustainability report (SR), as well as actioned remedial policies that constitute the crisis plan – and how the company went about interacting with stakeholders during and after the immediate crisis period. We conducted a content analysis of ACC disclosures and assessed Petrobras's remedial activities in the eight-year period 2010–2017 as disclosed in its ARs, SRs and press releases. We find firstly that, consistent with legitimacy theory, Petrobras responded by voluntarily and substantially increasing its relevant disclosures so as to regain legitimacy, a finding which mirrors those found elsewhere following corruption and environmental crises. Secondly, the unique corporate governance situation at Petrobras combined with the fact that leadership was allegedly implicated in the scandal, led the post-crisis management team to undertake a series of remedial actions that prioritised the need to take and maintain executive control and independence from the government, whilst at the same time carefully managing the relationship with this influential stakeholder: - actions which argue strongly in favour of stakeholder-agency theory and multiple agency theory interpretations of the nature of stakeholder interactions that transpired during the crisis period of disequilibrium, and which precluded the type of stakeholder dialogue seen in some previous environmental crisis situations. Finally, we show that Petrobras's crisis management response actions align well with models of trust repair and legitimacy management, and suggest the company considered it had successfully regained legitimacy by 2017
An improved implicit direct-forcing immersed boundary method (DF-IBM) around arbitrarily moving rigid structures
Get PDFAn improved implicit direct-forcing immersed boundary method (DF-IBM) is presented for simulating incompressible flows around complex rigid structures undergoing arbitrary motion. The current approach harnesses the pressure implicit with splitting of operators algorithm to handle the fluid–solid system's dual constraints in a segregated manner. As a result, the divergence-free condition is preserved throughout the Eulerian domain, and the no-slip velocity boundary condition is exactly enforced on the immersed boundary. A new pressure Poisson equation (PPE) is derived, incorporating the boundary force where the no-slip condition is already met, enabling the use of fast iterative PPE solvers without modifications. The improvement involves integrating Lagrangian weight methods having better reciprocity over the IBM-related linear operators with the implicit formulation. An additional force initialization scheme is introduced to further boost the algorithm's performance. The method's accuracy, efficiency, and capability are verified through various stationary and moving immersed boundary cases. The results are validated against experimental and numerical data from the literature. The proposed improvements seamlessly integrate into existing incompressible fluid solvers with minimal adjustments to the original system equations, highlighting their ease of implementation.This research was supported by the UK Engineering and Physical Sciences Research Council (EPSRC) (Grant No. EP/T518104/1, Project Reference No. 2676291).Physics of Fluid
Preliminary design exploration of prospective multirotor aerobots
Get PDFThe groundbreaking success of NASA's Ingenuity Helicopter has spurred immense potential for Martian exploration, emphasizing the pivotal role of aerobots alongside rovers and landers. However, the helicopter's limitations, stemming from its compact and simplistic design, are apparent in its restricted long-range endurance and payload capacity. This paper suggests a feasible optimisation approach for Martian rotorcraft concepts while addressing constraints and progressing Martian drone technology. The key focus lies in improving performance to meet the evolving demands of forthcoming Martian aerobot missions. Based on a comprehensive parametric analysis rooted in simplified rotorcraft momentum theory, this study focuses on power requirements of rotorcrafts with single, coaxial, tandem, quad and hexa rotors for hover, vertical climb, and forward flight segments. Modified to meet more demanding mission criteria, these designs are limited by the spacecraft aeroshell's maximum size for safe transport to Mars. Among the considered configurations, the hexacopter emerged as the most efficient choice, offering a balance between performance, endurance, and payload capacity, while a conventional single main rotor configuration fell short within the specified parameters.34th Congress of the International Council of the Aeronautical Sciences (ICAS
Regrowth of microorganisms from treatment to tap in operational drinking water supply networks
Get PDFThe 3rd International Joint Conference on Water Distribution Systems Analysis & Computing and Control for the Water Industry (WDSA/CCWI 2024). 1-4 July 2024, Ferrara, ItalyThis research provides new understanding of the (re)growth of microorganisms within drinking water distribution networks. Flow cytometry data quantifying total and intact cell counts from consumers’ taps are currently rare, and its value for aiding understanding of the growth of microorganisms is unknown. In this study, changes in microbial concentrations from the treatment works to customers’ taps were measured (using flow cytometry) in two UK drinking water distribution networks. Throughout each network, five locations were sampled for five consecutive days within a week, and to assess seasonal impacts, this was repeated twice in each network. Significant growth of microorganisms was observed in both networks during autumn, particularly at higher-water-age taps. These results give novel emphasis to the active impact of the distribution system on microbiological growth by using flow cytometry data collected in a systematic way from treatment through to customers’ taps. Such understanding is essential to achieving the delivery of safe and aesthetically pleasing drinking water to customers.Engineering and Physical Sciences Research Council (EPSRC)This research was funded by WIRe CDT Ph.D. studentship (EPSRC EP/S023666/1), jointly funded by the EPSRC (Engineering and Physical Sciences Research Council) and UKWIR (UK Water Industry Research).International Joint Conference on Water Distribution Systems Analysis & Computing and Control for the Water IndustryEngineering Proceeding
Multi-fidelity multi-disciplinary optimisation of propeller design by visual analytics
Get PDFComputer Graphics & Visual Computing (CGVC) 2024, 12-13th September 2024, London, UKThis paper introduces a comprehensive framework for multi-fidelity, multi-disciplinary optimization of propeller design using visual analytics. The proposed methodology integrates advanced data visualization techniques, surrogate modelling and optimisation methodologies to handle high-dimensional data across various disciplines, including aerodynamics, aeroacoustics, and structures. By leveraging multi-fidelity simulations, the framework balances accuracy with computational efficiency, enabling detailed exploration and optimization of propeller designs. Interactive visualization tools in the framework facilitate the identification of optimal design parameters and trade-offs, highlighting its potential to improve decision-making in engineering design processes in terms of confidence and knowledge creation.This project has received funding from Innovate UK under Grant Agreement No 10003388.Computer Graphics & Visual Computing (CGVC) 202
Insights into sustainability and circular economy trends in luxury fashion: a LinkedIn topic modelling study
Get PDFThe fashion industry plays a pivotal role in societal evolution and economic growth, yet it also stands as a significant contributor to environmental degradation. In response, the concept of slow fashion has been gaining increased attention in recent years, offering sustainable and circular alternatives to fast fashion. Luxury fashion, traditionally known for its heritage, exclusivity, and craftsmanship, exhibits elements similar to slow fashion, thereby exerting considerable influence on industry trends and consumer behaviour. This study explores the drivers shaping the luxury fashion landscape and the evolving circular economy and sustainability trends within the UK, a key global influencer in the luxury fashion domain. Luxury fashion's impact extends beyond its niche market, often setting benchmarks for innovation and sustainable practices that influence the broader fashion industry. Leveraging readily available qualitative and quantitative data from LinkedIn profiles, this research employs Latent Dirichlet Allocation analysis to uncover relevant topics within a dataset comprising 1115 companies registered in the “Apparel and Fashion” and “Textiles” industries. Five key drivers emerge, including Artful Creations in Fashion, Time-Honoured Craftsmanship, The Art of Style and Design, The Pinnacle of Retail Excellence, and A Personalised Style Experience. Additionally, utilising the Google Collab Platform and Python language, this study identifies circular economy and sustainability trends within luxury fashion. While approximately 20% of the companies studied actively emphasise sustainability, circular economy requires comparable attention. This research provides industry stakeholders and scholars with valuable insights into sustainable and circular practices, thus guiding innovation and informed decision-making in the fashion industry.Cleaner and Responsible Consumptio