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Online prize draws and competitions : Gambling products outside the United Kingdom regulatory framework
(2026-09) McGarrigle, Jack; Torrance, Jamie; Quigley, Martyn; Dymond, Simon; Department of Psychology
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Profitability in a resource-based industry: : Evidence from Icelandic fisheries, 1990–2022
(2025-09-19) Gunnlaugsson, Stefán Bjarni; Faculty of Business Administration
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On high-accuracy global corrosion parameter determination in metallic plates using multi-random-field inverse surrogates
(2026-08-01) Koziel, Slawomir; Pietrenko-Dabrowska, Anna; Zima, Beata; Department of Engineering
The accurate assessment of global corrosion characteristics in metal plates, particularly thickness loss and surface roughness, is critical for industries such as oil, marine, and energy. Recent advances using guided ultrasonic waves have enabled non-destructive evaluation of corroded structures; however, this task remains challenging due to complex interactions between wave propagation and spatially varying thickness profiles. The difficulty is further compounded by the inherently heterogeneous nature of real corrosion patterns, which introduces significant uncertainty in signal interpretation and limits the effectiveness of traditional physics-based identification methods. In this study, global corrosion parameters, including mean thickness reduction and thickness standard deviation, are reliably estimated using data-driven inverse surrogate models. Corrosion morphology is modeled as a stochastic field, while guided wave responses are generated via numerical simulations. The inverse framework maps features extracted from wave responses to corresponding corrosion parameters. A key challenge lies in the pronounced non-uniqueness of the problem, as infinitely many stochastic field realizations can yield identical statistical descriptors. To address this issue, a multi-random-field strategy is introduced, in which guided wave responses from multiple independent realizations are averaged and jointly analyzed. Extensive comparative studies show a clear improvement in prediction accuracy with as few as three random field realizations, with further significant gains observed for ten random field configurations. For the considered test cases, the relative mean absolute error was reduced to approximately 1.4% for thickness reduction estimation and 7.0% for standard deviation estimation. Across all cases, the proposed inverse modeling approach outperforms conventional time-of-flight-based identification methods derived from dispersion curve analysis. Although this research focuses on computational modeling, in practical applications, the proposed methodology can be readily implemented by repositioning the sensor network or excitation source, either laterally or rotationally.
Verk
Meta-lens-based circularly polarized fixed-beam antenna for high-gain wideband millimeter-wave applications
(2026-12) Ullah, Ubaid; Koziel, Slawomir; Pietrenko-Dabrowsks, Anna; Department of Engineering
A planar metamaterial lens-based single-element circularly polarized (CP) antenna for millimeter wave (mm-wave) band applications is presented. The proposed antenna consists of a modified patch excited by a single-point-fed coaxial probe and two displaced layers of a novel meta-lens design. The modified structure allows for the simultaneous excitation of orthogonal components with equal magnitudes. To realize the gain enhancement of the proposed design, a novel meta-lens is designed based on meta-atoms of subwavelength size arranged in a disconnected cross-shape repeated pattern. To effectively focus the outgoing CP wave radiated by the antenna, the focal distance is meticulously optimized. Two layers of the same lens are used to enhance the antenna gain. Following a rigorous numerical analysis and optimization, the proposed design is fabricated and experimentally validated. The comparison of the results with the lens and without the lens illustrates that a 4 dB gain improvement is attained with the compact lens configuration. Furthermore, the antenna features a wide impedance bandwidth (S11) from 24 GHz to 31 GHz and the axial ratio (AR) below 3 dB within the same operating band. The proposed design offers multiple advantages, including a simple geometrical configuration, light in weight, and ease of integration due to the planar lens structure. The proposed antenna is suitable for multiple modern communication systems, including short-range radar systems and other line-of-sight mm-wave applications requiring fixed-beam and high data rates.
Verk
Low-cost Kirigami-inspired deployable dual-polarized MIMO antenna with angular pattern diversity
(2026-12) Shah, Sayed Sabir; Koziel, Slawomir; Bashir, Shahid; Ullah, Raza; Ullah, Sadiq; Alatwi, Aadel Mohammed; Shah, Syed Imran Hussain; Department of Engineering
This work presents a low-cost, easy-to-fabricate, kirigami-inspired deployable MIMO antenna operating at 2 GHz, featuring dual polarization and angular pattern diversity. Inspired by the Yagi antenna design, the proposed MIMO antenna comprises two orthogonally oriented antennas, each consisting of a rectangular radiating element (monopole) and one parasitic rectangular strip (director). These are integrated onto a foldable, staircase-shaped Kirigami structure made of polyethylene terephthalate (PET) sheet. Each antenna includes a reflector attached to the Kirigami structure’s back. Operating at 2 GHz, the antenna achieves a measured peak gain of 9 dBi with a -10 dB impedance bandwidth of 630 MHz (1.82 GHz to 2.45 GHz). Mutual coupling between the radiating elements is maintained below -15 dB, and the total efficiency exceeds 80% across the operating band. The antenna system meets MIMO specifications, demonstrating an Envelope Correlation Coefficient (ECC) below 0.0025 and a Channel Capacity Loss (CCL) below 0.35 bps/Hz. This combination of high performance, low cost, and ease of fabrication makes the proposed design a promising candidate for diverse microwave applications.

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