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Machine learning‐assisted direction‐of‐arrival accuracy enhancement technique using oversized lens‐loaded cavity
Get PDFThis paper presents a framework for achieving machine learning (ML)-assisted direction-of-arrival (DoA) accuracy enhancement using a millimetre-wave (mmWave) dynamic aperture. The technique used for the enhanced DoA estimation accuracy leverages an over-sized lens-loaded cavity antenna connected to a single RF chain in the physical layer and a computational method in the computational layer of the framework. It is shown for the first time that by introducing a reconfigurable mode-mixing mechanism inside the over-sized lens-loaded cavity hardware, a greater number of spatially orthogonal radiation modes can be achieved giving rise to many cavity states. If the best cavity state is determined and selected by means of design exploration using a contemporary ML-assisted antenna optimisation method, the computational DoA estimation accuracy can be improved. The mode-mixing mechanism in this work is a randomly oriented metallic scatterer located inside an over-sized constant−ϵr lens-loaded cavity, connected to a stepper motor that is electronically controlled by inputs from the computational layer of the presented framework. Measurement results in terms of near-field radiation mode scans are included in this study to verify and validate that the proposed ML-assisted framework enhances the DoA estimation accuracy. Moreover, this investigation simultaneously provides a simplification in the physical layer implementation of mmWave radio hardware, and DoA accuracy enhancement, which in turn lends itself favourably to the adoption of the proposed framework for channel sounding in mmWave communication systems
Machine Learning-Assisted Optimization of a Metasurface-Based Directly Modulating Antenna
Get PDFA directly modulating antenna using metasurfaces is optimized using the surrogate model assisted differential evolution for antenna synthesis (SADEA) method and simulated. Metasurface modulation holds promise as an energy efficiency transmitter technology, but suffers from modulation distortion and many differing parameters, making achieving good designs difficult. The algorithm used here, SADEA, obtained a design that shows improvement over conventional design techniques, producing amplitude variation of 1.8 dB over 360° and an average efficiency of 65%, up from 50% obtained by the standard model
The Magic of Paint
Get PDFThe purpose of this chapter is to demonstrate how painting can enhance the wellbeing of people living with dementia. Arts in health is a developing area that is now recognised as a means to improve people’s health and wellbeing while
supporting current major health and social care demands. With dementia being the largest social and health care challenge in the United Kingdom, it is imperative to develop new, creative ways of improving the lives of those living with or affected by the condition.
Painting can provide new forms of purposeful experience and engagement for people living with dementia, which can improve their wellbeing. This is important and should be recognised as an alternative pathway in supporting people living with the condition to create meaningful experiences
Applied Artificial Intelligence in Manufacturing and Industrial Production Systems: PEST Considerations for Engineering Managers
Get PDFPresently, artificial intelligence (AI) is playing a leading role in our contemporary world via numerous applications. Despite its many advantages, analytical frameworks highlighting the implications of AI applications are still evolving. Particularly, in manufacturing and industrial production where novel technologies are continuously being harnessed. Consequently, AI and the implications of its applications have relatively remained a gray area for many engineering managers who are key players in the gravitation of manufacturing and industrial production toward the fourth industrial revolution and more recently, the fifth industrial revolution, generally termed as Industry 4.0 (I4.0) and Industry 5.0 (I5.0), respectively. In this study, the implications of AI applications in the general context of manufacturing and industrial production, are presented to provide insight for engineering managers. These implications are discussed via political, economic, social, and technological (PEST) considerations of the broad impact of the adoption of AI techniques in manufacturing and industrial production systems. A new engineering management model has not been proposed in this article. Rather, a discussion aimed at serving as a tool for the appraisal of the implications of the general applications of AI by engineering managers, who may not be AI specialists or data science experts is presented
A Wideband Low-RCS Metasurface-Inspired Circularly Polarized Slot Array Based on AI-Driven Antenna Design Optimization Algorithm
No full textA metasurface (MS)-inspired low-profile circularly polarized (CP) slot array with a wide CP band and broadband low radar cross section (RCS) is proposed in this communication. The slot array consists of four element antennas, four grounded substrates, and a sequential-rotated feeding network. In terms of radiation performance, the array yields a wide CP band resulting from the CP element antenna and the sequential-rotated feeding network. The CP element antenna is achieved due to the polarization conversion property of the MS-based superstrate. The feeding network with multiple related design parameters is optimized by an artificial intelligence (AI)-driven antenna design method to find the widest bandwidth. In terms of scattering performance, broadband RCS reduction is achieved by using a hybrid RCS reduction technique that combines two destructive interference principles. The |S11|<−10 dB bandwidth reaches 53.2%, the AR < 3 dB bandwidth reaches 50%, and the RCS reduction bandwidth reaches 147.8% for a low-profile structure with a relatively low number of MS unit cells. A prototype was fabricated and measured. The measured and simulated results are in good agreement
Development of a measure for assessing victimisation at UK universities
Get PDFSchool bullying has been researched extensively, yet research on student bullying at university is still in the early stages and lacks valid measurement instruments. This paper outlines three studies conducted to develop a new scale to measure victimisation and perpetration at university (ultimately focusing on victimisation). Wider bullying literature from the school context and the workplace was consulted alongside an initial qualitative study exploring students’ perceptions of university bullying. For Study One, an exploratory factor analysis on data from a sample of UK university students (N=243) resulted in a reliable scale with four factors: (1) psychological victimisation, (2) physical act/trace victimisation, (3) social victimisation, and (4) direct verbal victimisation. After modification, Study Two tested the altered structure of the scale on a new sample of UK university students (N=304), finding two alternative two- and three-factor models. Study Three tested the competing models from the first two studies using confirmatory factor analysis (N=441), finding the four-factor structure to be the best model out of the three, but with the scale requiring further work. Although none of the fit indices’ statistics were ideal, this is the first attempt to design a higher education bullying scale based on a multi-phase approach, which shows potential as a useful tool for measuring victimisation following further research
Temperature gradient improvement of power semiconductor modules cooled using forced air heat sink
Get PDFThis paper discusses the improvement of operational reliability and lifetime of power electronic modules due to the reduction of the temperature gradient in the semiconductor structures. High temperature gradient in the power electronic modules having a large area of the semiconductor structure is a more affecting issue than the junction temperature. The improvement in the temperature gradient is achieved by varying/degrading the thermal resistance along the heat sink length. A conventional cooling system for three semiconductor modules based on a forced air heat sink was modelled and analysed to derive a reduction rate of the appropriate thermal resistances. Implementation of the forced air heat sink having non-uniformed thermal resistances along the heat sink length ensures the uniform temperature distribution across the power semiconductors and, therefore, the improved thermal gradient
How to be a Posthuman
Get PDFThe digital exhibition How to Become a Posthuman is part of the collective artistic research project Fabulation for Future, which is based on the call for deputies to form the fictive International Committee to Save the Earth through Speculative Fabulation. The international committee deputies met online for the first time in September 2021: during an online symposium Intra-Activity: the Posthuman, Fabulation and Matter and an online workshop, the deputies unfolded fabulative concepts and intertwined their approaches. These were sympoietically developed further in a subsequent 9-month project process and are now presented in the digital exhibition. Physical continuations of the exhibition are planned for 2023 under the title Games of Becoming
Investigation of rheological behaviors of aqueous gum Arabic in the presence of crystalline nanocellulose
No full textAn investigation on the effects of addition of crystalline nanocellulose (CNC) on both the intrinsic viscosity and rheological behavior of gum Arabic (GA) is undertaken. An adapted, facile method of CNC synthesis from microcrystalline cellulose (MCC) is used. At low concentrations of both CNC and GA, intrinsic viscosity of GA appears unaffected. However, the rheological behavior of 20 wt% and 40 wt% GA solutions is markedly affected by the introduction of CNC, even at very low concentrations. Enhanced viscosity and shear thinning properties are demonstrated with increased addition of CNC within the range studied, as are similar increases in storage modulus. Mechanisms are proposed for interactions between GA and CNC that may cause the observed effects, based on previous studies found in the literature. The use of CNC as a food grade viscosity modifier of GA and likely other polymer solutions is confirmed, and suggestions for further investigation are provided
Numerical Analysis of an Electric High-Speed Rim-Driven Rotor
Get PDFFinite element analysis was conducted to study the stress behaviour in a generic electric high-revolution rimdriven rotor in relation to the number of spokes and rotational speed using the maximum distortion energy failure criterion. The paper analysed the stresses on an electric high-revolution rotor and locate the failure’s potential origins. Upon analysing the FEA results, it is found that the maximum equivalent von-Mises stress is related to the square of revolution in RPM. It is concluded that it is possible to create a general formula that can predict the stresses, simplifying the development stage of an electric rim-driven rotor for high-speed applications