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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.
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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.
Verk
Investigation of Heart Rate Variability Indices in Motion Sickness
(2026-04) Ponsiglione, Alfonso Maria; Guerrini, Lorena; Pierucci, Simona; Santoriello, Vittorio; Romano, Maria; Recenti, Marco; Petersen, Hannes; Gargiulo, Paolo; Ricciardi, Carlo; Department of Engineering
Motion sickness (MS), or kinetosis, is a condition experienced by some individuals in response to rhythmic or irregular body motion. Multiple studies have explored its neurobiological mechanisms and countermeasures, with the sensory-conflict hypothesis remaining the most accepted explanation. Heart-rate variability (HRV) and electrocardiography provide complementary autonomic nervous system perspectives that may support MS assessments. From an applied viewpoint, reliable HRV markers could enable the early detection and continuous monitoring of MS in real-world contexts, such as autonomous vehicles, where passenger comfort and safety are critical, motivating contact-free cardiac sensing for unobtrusive monitoring. This systematic review examines the value of HRV indices in MS, conducted under PRISMA guidelines across PubMed, Scopus, and the Web of Science. The included studies were grouped into four categories based on the methods used to induce MS: mechanical stimulus, real trip, visual stimulus, and virtual reality. Aggregated findings indicate that frequency–domain metrics, particularly the low frequency (LF)/high frequency (HF) ratio, HF power, and mean heart rate (mHR), are most frequently reported in relation to MS. Overall, autonomic dysregulation likely contributes to MS susceptibility, but standardized protocols are needed to validate HRV as a reliable marker.
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Introduction to the 9th Annual Lifelog Search Challenge, LSC'26
(Association for Computing Machinery, Inc, 2026-06-15) Tran, Allie; Bailer, Werner; Dang-Nguyen, Duc Tien; Healy, Graham; Hodges, Steve; Jónsson, Björn Þór; Hürst, Wolfgang; Rossetto, Luca; Schoeffmann, Klaus; Tran, Minh Triet; Zhou, Liting; Gurrin, Cathal; Department of Computer Science
The ACM Lifelog Search Challenge (LSC) is an annual comparative benchmarking exercise that brings together researchers in the field of multimedia retrieval to evaluate interactive search systems using a large-scale multimodal lifelog dataset. This paper presents an overview of the ninth edition of the challenge (LSC'26), held as a workshop during the ACM International Conference on Multimedia Retrieval (ICMR '26) in Amsterdam. To broaden its scope, the workshop now features three submission tracks: the traditional Challenge Track for real-time search performance, a new General Lifelog Research Track for theoretical and architectural advancements, and an additional Open Source Track aimed at enhancing reproducibility and reducing barriers to entry for new participants.
Verk
Governing fisheries for sustainability : How ITQs can contribute to the SDGs
(2025-10-23) Gunnlaugsson, Stefán Bjarni; Faculty of Business Administration

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