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Ethical concerns about social media privacy policies: do users have the ability to comprehend their consent actions?
Get PDFSpecial issue: Irresponsible Marketing and the Manipulation of Public Opinion. Guest editors: Steven J. Greenland, Ninh Nguyen, and Carolyn StrongSocial media platforms capture and trade consumer data for analysis, user profiling and for sale to interested parties and is used extensively in marketing. To collect, store, process and resell this data, they are legally required to obtain informed consent. However, users may agree to consent without the ability to comprehend the consequences of what that consent means. In this article we examine the complexity of privacy policies and raise ethical concerns about the ability of users to comprehend their consent actions. Using readability scores and reading fluency instruments, we analyzed the accessibility of privacy policies from a major social media platform (Meta) and a smaller platform (Twitter). Findings indicate that due to reading fluency and document length it is unlikely all users, especially minors, can authorize the consent actions which raises ethical concerns. Practical implications for managers and policy makers are also discussed and regulators may need to review users’ access to platforms where they lack the ability to comprehend their consent actions.Journal of Strategic Marketin
Assuring safe and efficient operation of UAV using explainable machine learning
Get PDFThe accurate estimation of airspace capacity in unmanned traffic management (UTM) operations is critical for a safe, efficient, and equitable allocation of airspace system resources. While conventional approaches for assessing airspace complexity certainly exist, these methods fail to capture true airspace capacity, since they fail to address several important variables (such as weather). Meanwhile, existing AI-based decision-support systems evince opacity and inexplicability, and this restricts their practical application. With these challenges in mind, the authors propose a tailored solution to the needs of demand and capacity management (DCM) services. This solution, by deploying a synthesized fuzzy rule-based model and deep learning will address the trade-off between explicability and performance. In doing so, it will generate an intelligent system that will be explicable and reasonably comprehensible. The results show that this advisory system will be able to indicate the most appropriate regions for unmanned aerial vehicle (UAVs) operation, and it will also increase UTM airspace availability by more than 23%. Moreover, the proposed system demonstrates a maximum capacity gain of 65% and a minimum safety gain of 35%, while possessing an explainability attribute of 70%. This will assist UTM authorities through more effective airspace capacity estimation and the formulation of new operational regulations and performance requirements.Drone
A mathematical examination of the impact of mould transparency to infrared radiation on solidification during the investment casting process
Get PDF16th International Conference on Modelling of Casting, Welding and Advanced Solidification Processes (MCWASP 2023) 18-23 June 2023 Banff, CanadaInvestment casting is a highly dynamic process during which multiple competing physical phenomena are at work. Those seeking to understand and simulate such processes computationally are confronted with a considerable task, balancing accuracy with efficiency. Approximations and models based on well-understood and documented fundamental physics are powerful tools in a modeller's arsenal. Driven by observed discrepancies between experimental thermocouple measurements and simulation predictions of casting temperatures, this work explores the additional alloy cooling mechanism of mould transparency to infrared radiation, targeting a new mathematical approximation applicable in such situations. Direct attenuation, scattering from coarse sand, sand distribution in the mould and material temperatures play a role in the extent of radiation transparency that must be considered. From this model, estimation of the additional cooling rate resulting from expected mould transparency can be determined and applied as a corrective measure to computation fluid dynamics (CFD) simulation results that do not capture this phenomenon.16th International Conference on Modelling of Casting, Welding and Advanced Solidification Processes (MCWASP 2023)IOP Conference Series: Materials Science and Engineerin
Application of model-based systems engineering for the integration of electric engines in electrified aircraft
Get PDFThe objective of green, carbon-neutral flights is propelling the innovation of newer propulsion systems. With this increased development of an interdisciplinary form of propulsion for aircraft, the integration burdens and efforts intensify. In literature, it is estimated that it takes 10-15 years to design and develop an aircraft. The expected date of entry for any hybrid electric aircraft is 2035-2040. Any innovation and effort to cut this time by any degree should be explored and analysed. One of the techniques that have the potential to help fast-track the research and development of interdisciplinary systems is Model-based System Engineering (MBSE). Various studies have shown the benefit of employing a model-based design strategy. The focus case study relates to the integration of the electric machine and the propeller, along with related sub-systems. For Hybrid Electric Propulsion (HEP), the electric machine and propeller need to be integrated and their interaction to be analysed. MBSE is proposed as a methodology that would help streamline the process of design and integration of the two systems. This study documents the exploration of connecting MBSE with current simulation and modelling of sub-systems in order to ensure the fulfilment of stakeholder needs and full system effectiveness. This paper establishes the research problem, and the approach to be pursued, and gives notice of first developments and expected follow-up work.12th EASN International Conference on "Innovation in Aviation & Space for Opening New Horizons" 2022,Journal of Physics: Conference Serie
Modelling wind turbine power curves based on Frank’s copula
Get PDFPresented at: 21st International Conference on Renewable Energies and Power Quality (ICREPQ’23)In the study of wind turbines, one of the most relevant and useful indicators is the power curve. It has been shown to be of paramount importance in evaluating turbine performance and therefore reducing operation and maintenance (O&M) costs. Various techniques can be applied to model and obtain the shape of this curve, which relates the electrical power generated by a turbine to the wind speed. Statistical copulas are used in this paper, a tool used in other fields such as econometrics, and whose potential lies in its ability to capture the complex dependency between the variables involved. In particular, the Frank copula is applied to obtain a probabilistic model of the power curve of a wind turbine. This model is compared with the Gaussian Mixture Model, a technique widely used to obtain parametric probabilistic models. As a result of this comparison, it is observed that the Frank copula model fits the power curve of the wind turbine with greater precision and reliability, which would allow its use for prediction and fault detection.Renewable Energy and Power Quality Journa
Characterising flow with continuous aeration in an oscillatory baffle flow reactor using residence time distribution
Get PDFMulti-phase flow occurs in many reactions with gas, an integral part of the reaction. This study assesses the synergistic impact of continuous aeration and velocity ratio on mixing conditions within an oscillatory baffled flow reactor to enhance the degree of plug flow, quantified by a tanks-in-series (TiS) model. A bubbly flow regime is shown in all experiments. In most cases, the TiS value was reduced with gas flow, and a maximum TiS value of 23.6 was achieved at a velocity ratio of 3.8 at 225 ml min−1 in a counter-current direction. Single-phase runs and co-current multi-phase runs produced maximum TiS values of 23.5 and 18.2 respectively at a velocity ratio of 2.2. Regardless of the gas flow rate, the velocity ratio was found to be the most influential factor that dictates the level of plug flow within the OBR. A predictive model is developed and used to maximise the mixing efficiency by determining the level of plug flow within the OBR at selected amplitudes, frequencies, and gas flow rates.Reaction Chemistry and Engineerin
A fibre optic angle sensing tape for applications in robotics and automation
No full textA dual-fibre single-plane angle-sensing tape that utilizes optical Fibre Segment Interferometry and Range- Resolved Interferometry (RRI) for angle sensing is presented. The sensing tape facilitates the multiplexing of an array of angle sensors along its length and can be retrofitted into small robots and construction equipment. We demonstrate its application on three non-rotational joints of a small five-axis robot, describing the design, construction, measurement principle, and presenting measurement results. Preliminary data shows that the angles measured by the sensing tape exhibited agreement within a range of ±0.005° with the manufacturer-installed angle encoder of the robot.SPIE Optical Metrology. Optical Measurement Systems for Industrial Inspection XIII, 202
Characterisation of human tissues analogues for ballistic testing
Get PDFBallistic testing necessarily employs simulant target materials for ethical and fiscal reasons. Current tissue analogues utilised for ballistic testing / research are, however, typically relatively simplistic – such as ballistics soap or gelatin. Consequently, these materials are seldom representative of complex mammalian constructs. In this paper the authors have drawn together core elements of previously published in-house research with the aim of providing insight into potential approaches to create a composite simulant solution. In particular, tissue analogues covering the epidermal, epithelial, connective, muscular and skeletal components are presented. These results highlight the complementary nature of employing a range of tissue simulant materials and, in parallel, the importance – if ballistic testing data is to be truly representative – of fully understanding the nature of the analogues employed.56th UK Human Responses to Vibration Conferenc
Analysis of triangular cross-section slender bodies in supersonic regime using RANS simulations
Get PDFThis paper presents an investigation on the ability of RANS simulations to capture the aerodynamic forces and the flow topology of triangular cross-section slender bodies. At Cranfield University’s Transonic and Supersonic Wind Tunnel, force measurements and Schlieren images were obtained at zero incidence, Mach number equals to 2.5, and Reynolds number of 2.38 · 10^5 (based on section width). Tests were performed for three bodies of different nose geometries, but constant nose fineness ratio of 1.732. Tests were compared with RANS simulations for three turbulence models: Spalart-Allmaras, k− epsilon Realizable and k − omega SST using the ANSYS Computational Fluid Dynamics software Fluent. In addition, simulations for a configuration presented in the literature which investigated several angles of attack were also conducted. At Mach 2.5, the normal force was predicted accurately by all turbulence models. The axial force, however, was clearly predicted more accurately with the k − epsilon Realizable model. At the other hand, this turbulence model showed inferior ability to capture the flow features, particularly the leeside vortices. Spalart-Allmaras and k − omega SST gave similar results.2023 AIAA Aviation and Aeronautics Forum and Exposition (AIAA AVIATION Forum
Do temperature and moisture conditions impact soil microbiology and aggregate stability?
Get PDFPurpose: Studies predicting the impacts of climate change on erosion have considered numerous variables, such as rainfall erosivity and vegetation cover, but have not considered potential changes in soil erodibility. Erodibility is an intrinsic property of the soil, strongly correlated with the stability of soil aggregates. It is influenced by soil physico-chemical attributes, including the microbiological community. The study aim was to determine how shifts in temperature and moisture conditions, which other studies have shown affect microbiological communities, might affect aggregate stability.
Methods: Using an experimental approach with laboratory microcosms, aggregates from a sandy loam soil and a clay soil were incubated at three temperatures and three moisture conditions in a factorial experimental design. Aggregate stability was quantified using rainfall simulation. Microbiological indicator metrics were measured to evaluate treatment microbiological impacts, including community composition (PLFA), biomass carbon, and respiration.
Results: Temperature and moisture content affected aggregate stability significantly, but differently for the two soil types tested. For the sandy loam soil, aggregate stability decreased significantly with increasing moisture content. For the clay soil, aggregate stability increased significantly with increasing temperature. For both soil textures, temperature and moisture content affected microbiological community composition and respiration. Regression analysis indicated that microbiological properties were significant predictors of aggregate stability.
Conclusion: Our results emphasise the dynamic nature of soil aggregate stability. Changes in microbiological metrics suggest possible biological mechanisms for aggregate stability changes, which should be investigated further to better understand the potential impacts of climate change on soil erodibility and erosion.Natural Environment Research Council (NERC): NE-M009106-1
BBSRCJournal of Soils and Sediment