http://trepo.tuni.fi:80/handle/10024/105878 2026-07-14T19:19:16Z http://trepo.tuni.fi:80/handle/10024/239158 ORIX: Orchestration of RIS With xApps for Smart Wireless Factory Environments Kayraklik, Sefa; Sahin, Ali Fuat; Salan, Onur; Tasci, Recep A.; Vural, Recep; Tek, Yusuf Islam; Basar, Ertugrul; Hokelek, Ibrahim; Gorcin, Ali; Boutiba, Karim; Ksentini, Adlen The vision of a smart wireless factory (SWF) demands highly flexible, low-latency, and reliable connectivity that goes beyond conventional wireless solutions. Reconfigurable intelligent surface (RIS)-empowered communications, when integrated with the open radio access network (O-RAN) architectures, have emerged as a promising enabler to meet these challenging requirements. This article introduces the methodology for the orchestration of RIS with xApps (ORIX), bringing the RIS technology into the O-RAN ecosystem through xApp-based control for SWF environments. ORIX features three key components: an O-RAN-compliant RIS service model for dynamic configuration, an RIS channel simulator that supports 3GPP indoor factory models with multiple industrial scenarios, and practical RIS optimization strategies with finite-resolution control. Together, these elements provide a realistic end-to-end emulation platform for evaluating RIS placement, control, and performance in SWF environments prior to deployment. The presented case study demonstrates how ORIX enables the evaluation of achievable performance gains, exploration of trade-offs among key RIS design parameters, and identification of deployment strategies that balance system performance with practical implementation constraints. By bridging theoretical advances with industrial feasibility, ORIX lays the groundwork for RIS-assisted O-RAN networks to power next-generation wireless communication in industrial scenarios. 2026-06-24T00:00:00Z http://trepo.tuni.fi:80/handle/10024/239157 COVID-19 Vaccinations, SARSCoV-2 Infections, and Type 1 Diabetes in Finnish Children Tall, Susanna; Pettersson, Jenni; Härkönen, Taina; Virtanen, Suvi M.; Vapalahti, Olli; Knip, Mikael OBJECTIVE We assessed whether 1) severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination is associated with the risk of type 1 diabetes and 2) SARS-CoV-2 vaccination or infection is associated with disease severity at type 1 diabetes diagnosis. RESEARCH DESIGN AND METHODS Every Finnish child aged 5–14 years diagnosed with type 1 diabetes (case subjects, n = 433) during a 16-month period (September 2021 to December 2022) were compared with three control subjects matched for age, sex, and municipality. Information on coronavirus disease 2019 (COVID-19) vaccinations was obtained from the National Vaccination Register. SARS-CoV-2 infections were identified based on circulating antibody titer in samples obtained soon after the diagnosis of type 1 diabetes. RESULTS COVID-19 vaccinations preceding type 1 diabetes diagnosis were not associated with risk of type 1 diabetes (hazard ratio 1.30, 95% CI 0.97–1.72, P = 0.076). Vaccinations were linked to less severe symptoms at the time of diagnosis. Children with protective HLA genotypes were more common among the vaccinated case subjects compared with unvaccinated case subjects. Vaccinations were inversely associated with insulin autoantibody positivity. There was no association between SARS-CoV-2 and type 1 diabetes symptoms or autoantibodies at the time of type 1 diabetes diagnosis. CONCLUSIONS There was no significant association between SARS-CoV-2 vaccination and risk of type 1 diabetes. Neither COVID-19 vaccinations nor SARS-CoV-2 infections explain the more severe symptoms at type 1 diabetes diagnosis observed in Finnish children after the beginning of the COVID-19 pandemic. Parents who vaccinate their children are more likely to seek medical care. This may result in less severe symptoms in their children at diagnosis of diabetes. 2026-01-01T00:00:00Z http://trepo.tuni.fi:80/handle/10024/239156 A 1.2-3.4 Gb/s Low-Power Multiphase CDR with Glitch-Free Bang-Bang Phase Detector Yun, Young-Ryul; Son, Min-Jeong; Jeon, Do-Yeon; Yoon, Ji-Seul; Yeo, Seung-Jin; Ko, Jae-Hong; Akram, Muhammad Abrar; Hwang, In-Chul This paper presents a multiphase clock and data recovery (CDR) circuit for high-speed (1.2-3.4 Gb/s) display driver ICs (DDIs) with a novel glitch-free bang-bang phase detector (BBPD). Compared to conventional BBPDs, which often suffer from sampling glitches caused by latch-delay mismatches and asynchronous data-edge interferences, the proposed BBPD employs a robust sampling network ensuring mutually exclusive data-edge valid events, thereby filtering invalid transitions and minimizing timing-induced jitter. An extensive comparison with conventional BBPDs highlights these improvements and clarifies how the proposed BBPD enhances phase detection integrity and overall stability in high-speed CDRs. Fabricated in a 0.18-μm CMOS process and integrated in a chip-on-film (COF) package along with other DDI's components, the proposed CDR demonstrates a clean output phase trajectory and an improved 97 ps output jitter (0.388 UI at 4 Gb/s) with only 20.1 mW power consumption including the equalizer power. The overall CDR performance is also validated through a comprehensive characterization using a shmoo plot across 1.4 V - 2.2 V supply voltages. 2026-01-01T00:00:00Z http://trepo.tuni.fi:80/handle/10024/239155 Broadband methods for stability assessment of double-star MMC based grid-forming STATCOM Dharmarathna, Eshan; Basnet, Hikmat; Tran, Minh; Kivimäki, Jyri; Roinila, Tomi Static Synchronous Compensators (STATCOMs) are key components in modern power grids, providing fast and accurate reactive power support to maintain voltage stability. When implemented using a double-star modular multilevel converter (MMC) in a grid-forming configuration, a STATCOM can also exchange active power, enhancing both voltage and frequency regulation. Reliable assessment of its dynamic behavior is essential for ensuring stable operation, as control-loop interactions between the converter and the grid can significantly influence overall system stability. Frequency-response measurements offer a powerful means of evaluating these dynamics, but conventional sine-sweep methods are too slow for real-time use due to their sequential nature. To address this limitation, this paper presents a broadband perturbation approach enabling fast, continuous, and comprehensive frequency-response characterization of a double-star MMC-based grid-forming STATCOM. Two excitation signals, Pseudorandom Binary Sequence (PRBS) and Discrete Interval Binary Sequence (DIBS), are employed, each providing benefits under different noise and disturbance conditions. Experimental validation on a three-phase prototype demonstrates that the proposed method achieves accurate and time-efficient dynamic characterization, establishing a practical foundation for real-time stability assessment of grid-forming STATCOMs. 2026-06-01T00:00:00Z