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This review paper highlights the recent developments in supercapacitors by pointing out the significance of appropriate electrode and device designs. We reported ten extremely high-performance supercapacitors with specific capacitance values among the highest available until now to the best of our knowledge. These state-of-the-art designs employing innovative electrode materials have been discussed along with their short descriptions. The supercapacitors collected here possess the most promising potential for facilitating next-generation systems in energy harvesting and storage. This review is just the surface that can help provide a pathway for supercapacitor research, which is still wide open for exploring and developing new advanced materials for energy applications of the future.

While the researchers have set their sights on future wireless networks of 2030, communications through reconfigurable intelligent surfaces (RISs) appears as one of the potential enabling technologies for 6G wireless networking. This article aims to shed light on the potential use-cases of RISs in future wireless systems by means of a novel channel modeling methodology as well as a new software tool for RIS-empowered millimeter-wave communication systems. It is shown by the open-source, user-friendly, and widely applicable SimRIS Channel Simulator, whose 2.0 version is proposed and goes online by this article, that RISs will work under certain use-cases and communication environments. Potential future research directions are also discussed to bridge the gap between the theory and practice of RIS-empowered systems towards their standardization for 6G wireless networks., Comment: to appear in IEEE Wireless Commmunications Magazine, code packages are available at https://corelab.ku.edu.tr/tools/SimRIS

Reconfigurable intelligent surface (RIS)-assisted communication appears as one of the potential enablers for sixth generation (6G) wireless networks by providing a new degree of freedom in the system design to telecom operators. Particularly, RIS-empowered millimeter wave (mmWave) communication systems can be a remedy to provide broadband and ubiquitous connectivity. This paper aims to fill an important gap in the open literature by providing a physical, accurate, open-source, and widely applicable RIS channel model for mmWave frequencies. Our model is not only applicable in various indoor and outdoor environments but also includes the physical characteristics of wireless propagation in the presence of RISs by considering 5G radio channel conditions. Various deployment scenarios are presented for RISs and useful insights are provided for system designers from the perspective of potential RIS use-cases and their efficient positioning. The scenarios in which the use of an RIS makes a big difference or might not have a big impact on the communication system performance, are revealed. The open-source and comprehensive SimRIS Channel Simulator is also introduced in this paper., Comment: to appear in IEEE Transactions on Communications, code packages are available at https://corelab.ku.edu.tr/tools/SimRIS/ -arXiv admin note: text overlap with arXiv:2006.00468

Reconfigurable intelligent surface (RIS)-assisted communication appears as one of the potential enablers for sixth generation (6G) wireless networks by providing a new way to optimize the communication system performance. This paper aims to fill an important gap in the open literature by providing an accurate, source, and widely applicable RIS channel model for mmWave frequencies. Our model is not only applicable in various indoor and outdoor environments but also includes the physical aspects of wireless propagation in the presence of an RIS as well as various practical 5G channel modeling issues. The open-source and comprehensive SimRIS Channel Simulator is also introduced in this paper to be used in computer simulations of RIS-assisted communication systems., Comment: Submitted for publication

In this work, we propose a new multiple-input multiple-output (MIMO) concept, which is called coordinate interleaved orthogonal design with media-based modulation (CIOD-MBM). The proposed two novel CIOD-MBM schemes provide improved data rates as well as diversity gain while enabling hardware simplicity using a single radio frequency (RF) chain. Moreover, using the equivalent channel model, a reduced complexity can be obtained for maximum likelihood (ML) detection of the proposed system. Using computer simulations, it is shown that CIOD-MBM schemes provide remarkably better performance against the conventional MBM and CIOD systems.

Reconfigurable intelligent surface (RIS)-empowered communication is one of the promising 6G technologies that allows the conversion of the wireless channel into an intelligent transmit entity by manipulating the impinging waves using man-made surfaces. In this paper, the potential benefits of using RISs are investigated for indoor/outdoor setups and various frequency bands (from sub 6 GHz to millimeter-waves). First, a general system model with a single RIS is considered and the effect of the total number of reflecting elements on the probabilistic distribution of the received signal-to-noise ratio and error performance is investigated under Rician fading. Also for this case, the path loss exponent is analyzed by considering empirical path loss models. Furthermore, transmission models with multiple RISs are developed and analyzed for indoor and outdoor non line-of-sight (NLOS) scenarios. The conventional RIS selection strategies are also integrated for systems equipped with multiple RISs for the first time. Through extensive simulations, it is demonstrated that the RIS-assisted systems provide promising solutions for indoor/outdoor scenarios at various operating frequencies and exhibit significant results in error performance and achievable data rates even in the presence of system imperfections such as limited range phase adjustment and imperfect channel phase estimation at RISs.

We report in situ neutron background measurements at the Kuo-Sheng Reactor Neutrino Laboratory (KSNL) by a hybrid neutron detector (HND) with a data size of 33.8 days under identical shielding configurations as during the neutrino physics data taking. The HND consists of BC-501A liquid and BC-702 phosphor powder scintillation neutron detectors, which is sensitive to both fast and thermal neutrons, respectively. Neutron-induced events for the two channels are identified and differentiated by pulse shape analysis, such that background of both are simultaneously measured. The fast neutron fluxes are derived by an iterative unfolding algorithm. Neutron induced background in the germanium detector under the same fluxes, both due to cosmic-rays and ambient radioactivity, are derived and compared with the measurements. The results are valuable to background understanding of the neutrino data at the KSNL. In particular, neutron-induced background events due to ambient radioactivity as well as from reactor operation are negligible compared to intrinsic cosmogenic activity and ambient $\gamma$-activity. The detector concept and analysis procedures are applicable to neutron background characterization in similar rare-event experiments., Comment: 12 pages, 29 figures

We report the performance and characterization of a custom-built hybrid detector consisting of BC501A liquid scintillator for fast neutrons and BC702 scintillator for thermal neutrons. The calibration and the resolution of the BC501A liquid scintillator detector are performed. The event identification via Pulse Shape Discrimination (PSD) technique is developed in order to distinguish gamma, fast and thermal neutrons. Monte Carlo simulation packages are developed in GEANT4 to obtain actual neutron energy spectrum from the measured recoil spectrum. The developed methods are tested by reconstruction of 241AmBe(\alpha, n) neutron spectrum., Comment: 12 pages, 32 figures

Neutrino-electron scatterings ($\nu - e$) are purely leptonic processes with robust Standard Model (SM) predictions. Their measurements can therefore provide constraints to physics beyond SM. Non-commutative (NC) field theories modify space-time commutation relations, and allow neutrino electromagnetic couplings at the tree level. Their contribution to neutrino-electron scattering cross-section was derived. Constraints were placed on the NC scale parameter $\Lambda_{NC}$ from $\nu - e$ experiments with reactor and accelerator neutrinos. The most stringent limit of $\Lambda_{NC} > 3.3 TeV$ at 95% confidence level improves over the direct bounds from collider experiments., Comment: 6 pages, 2 figures, 2 tables, V2: minor revisions to match published version

This study examined the effect of two computer literacy courses (one was offered online, and the other was offered through traditional methods) at the Middle East Technical University (Turkey). The two courses were compared in terms of their effectiveness on computer attitudes of student-teachers. The study also explored the other factors that contributed to changes in attitudes of the student teachers. The study used data from 209 (147 female, 62 male) student-teachers, of whom 69 attended the online course and 140 attended the traditional computer literacy course. Findings indicated that there is a combined effect of gender, computer literacy course type, whether any computer-related course was taken before, previous computer attitude, and possession of home computer on student-teachers' post-attitude towards computers. Follow-up study results also supported the results related to student-teachers' perceptions about the computer literacy course they attended. (Contains 11 references.) (Author/MES)