Köker, Abdulkadir
Tekinalp, Ozan
Yılmaz, Ü. Cezmi
Şakacı, Cemal
© 2021, Univelt Inc. All rights reserved.Sequential orbit determination using angle and range measurements for geostationary satellites is presented. The approach includes position, velocity and bias estimation with Unscented Kalman Filter. The measurements are taken from the actual ground station antennas at TURKSAT. In order to evaluate the accuracy and the robustness of the system, estimation is repeated with single and multiple ground station measurements for satellite T4B. Estimation results are compared with the reference orbit determination software and a very good agreement is obtained.
AAS/AIAA Astrodynamics Specialist Conference, 2020


Polat, Hakkı; Tekinalp, Ozan (2021-01-01)
© 2021, Univelt Inc. All rights reserved.Exploiting the propellant free maneuver capability of solar sail satellites for high resolution Earth observation mission is addressed with an elliptical low Earth orbit. The employed orbit has a low perigee altitude for observation and a high apogee altitude for orbit maneuvers. For the purpose of mission analysis of this new concept, a reference satellite configuration is designed with an aim to determine the technological readiness level based on the characteristi...
Advanced attitude determination algorithm for arase: Preliminary mission experience
Söken, Halil Ersin; Asamura, Kazushi; Nakamura, Yosuke; Takashima, Takeshi (2018-01-01)
© 2018 Univelt Inc. All rights reserved.JAXA’s ERG (Exploration of Energization and Radiation in Geospace) Spacecraft, which is nicknamed Arase, was launched on 20 December 2016. Arase is a spin-stabilized and Sun-oriented spacecraft. Its mission is exploring how relativistic electrons in the radiation belts are generated during space storms. Two different on-ground attitude determination algorithms have been designed for the mission: a conventional straightforward algorithm that inherits from old missions ...
Gaze Aversion In Conversational Settings: An Investigation Based On Mock Job Interview
Acartürk, Cengiz; Nawrocki, Piotr; Sniezynski, Bartlomiej; Jarosz, Mateusz; Usal, Kerem Alp (2021-01-01)
© 2021. Journal of Eye Movement Research All Rights Reserved.We report the results of an empirical study on gaze aversion during dyadic human-to-human conversation in an interview setting. To address various methodological challenges in assessing gaze-to-face contact, we followed an approach where the experiment was conducted twice, each time with a different set of interviewees. In one of them the interviewer’s gaze was tracked with an eye tracker, and in the other the interviewee’s gaze was tracked. The g...
Clinical validation of SERS metasurface SARS-CoV-2 biosensor
Bilgin, Buse; Torun, Hülya; İlgü, Müslüm; Yanik, Cenk; Batur, Sükrü Numan; Çelik, Süleyman; Öztürk, Meriç; Dogan, Özlem; Ergönül, Önder; Solaroglu, Ihsan; Can, Füsun; Onbasli, Mehmet Cengiz (2022-01-01)
© COPYRIGHT SPIE. Downloading of the abstract is permitted for personal use only.The real-Time polymerase chain reaction (RT-PCR) analysis using nasal swab samples is the gold standard approach for COVID-19 diagnosis. However, due to the high false-negative rate at lower viral loads and complex test procedure, PCR is not suitable for fast mass screening. Therefore, the need for a highly sensitive and rapid detection system based on easily collected fluids such as saliva during the pandemic has emerged. In t...
Unpredictable Solutions of Impulsive Quasi-Linear Systems
Akhmet, Marat; Tleubergenova, Madina; Nugayeva, Zakhira (2022-01-01)
© 2022. L&H Scientific Publishing, LLC. All Rights Reserved.The impulsive differential equations with unpredictable perturbations are under investigation. The definition of the discontinuous unpredictable function with the discrete unpredictable set of discontinuity moments is introduced. The existence and uniqueness of asymptotically stable discontinuous unpredictable solutions for quasi linear systems are proved. Examples with simulations are given to illustrate the results.
Citation Formats
A. Köker, O. Tekinalp, Ü. C. Yılmaz, and C. Şakacı, “SEQUENTIAL ORBIT DETERMINATION VERIFICATION FOR GEOSTATIONARY SATELLITES,” Virtual, Online, 2021, vol. 175, Accessed: 00, 2022. [Online]. Available: