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Yayın Channel modeling and characterization for VLC-based MBSNs impaired by 3D user mobility(IEEE, 2021-11-27) Dönmez, Barış; Miramirkhani, FarshadThis paper focuses on channel modeling and characterization of indoor visible light communication (VLC)-based medical body sensor networks (MBSNs) which establish links between light-emitting diodes (LEDs) and MBSNs nodes couple with photodetectors (PDs) placed on the shoulder (D1), wrist (D2), and ankle (D3) of the mobile user who walks over random trajectories in 3D scenarios of ICU ward and family type patient room. We adopt non-sequential ray-tracing to obtain channel impulse responses (CIRs) and channel characteristics over random trajectories. Based on simulation results, it is observed that channel DC gains exhibit sinusoidal behaviour for D1 and D2 except for D3 (i.e., due to the number of diffuse rays received at D3), as the user approaches and moves away from the luminaries. It is also revealed that a flat fading channel can be modeled if a data rate lower than 7.03 Mbit/s, i.e., sufficient for MBSNs applications, is chosen.Yayın Eastern Anatolia Observatory (DAG): the status in 2022, towards the first light(SPIE, 2022) Yeşilyaprak, Cahit; Keskin, Onur; Jolissaint, LaurentEast Anatolian Observatory's DAG telescope, with its 4m diameter primary mirror and VIS/IR observation capability, Eastern Anatolian Observatory's 4m diameter class DAG telescope, with VIS/IR observation capability, will be located on the Konakll-Karaya summit at an altitude of 3170 m, near the city of Erzurum, Turkey. DAG contains both active optics (aO) and adaptive optics (AO) systems. With the enclosure assembly nearly done, and the dummy mirror integration including the M1 cell integration performed at the end of 2021; DAG telescope's AIV is planned to take place by the end of May/2022 and the Provisional Acceptance by November/2022. DAG is equipped with an in-flange derotator-KORAY (K-mirror Optical RelAY) that will direct the light to the seeing limited Nasmyth platform containing TROIA (TuRkish adaptive Optics system for Infrared Astronomy). The scientific instruments that DAG will receive in 2022, are but not limited to, a stellar coronagraph and a 30"NIR diffraction limited camera. In his paper, a global status update and expected optical performance characteristics will be presented.Yayın A path loss model for vehicle-to-vehicle visible light communications(Institute of Electrical and Electronics Engineers Inc., 2019-07) Eldeeb, Hossien Badr; Miramirkhani, Farshad; Uysal, MuratThe increasing adoption of LEDs in exterior automotive lighting makes visible light communication (VLC) a natural solution for vehicular networking. In this paper, we consider a vehicle-to-vehicle link and propose a path loss expression as a function of distance and different weather conditions. We conduct ray tracing simulations and verify the accuracy of proposed expression. We further use this expression to derive the achievable transmission distance for a targeted data rate while satisfying a given value of bit error rate. Numerical results are presented to demonstrate the achievable distances for single and dual photodetector deployment cases.Yayın Eastern Anatolia Observatory (DAG): The status in 2020(SPIE, 2020) Yeşilyaprak, Cahit; Keskin, OnurEast Anatolian Observatory's DAG telescope, with its 4m diameter primary mirror and VIS/IR observation capability, will be located on the Konakll-Karaya summit at an altitude of 3170 m, near the city of Erzurum, Turkey. Containing both active optics (aO) and adaptive optics (AO) systems, the first light for DAG is expected for the last quarter of 2021. DAG will be equipped with an in-flange derotator - KORAY (K-mirror Optical relAY) that will direct the light to the seeing limited Nasmyth platform containing TROIA (TuRkish adaptive Optics system for Infrared Astronomy). DAG first generation instruments will consist in a 30"FoV near-infrared (NIR) diffraction limited camera and a stellar coronagraph. In his paper, status updates from DAG telescope will be presented in terms of; (i) DAG site, (ii) Site infrastructure, (iii) current status of the observatory building, (iv) DAG optics, (v) current status of the telescope, (vi) current status of enclosure, (vi) current progress of the astronomical instruments, and (viii) status of the Optomechatronics Research Laboratory - OPAL.
