[IEEE 2019 16th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology (ECTI-CON) - Pattaya, Chonburi, Thailand (2019.7.10-2019.7.13)] 2019 16th International Conference on Electrical Engineering/Electronics, Computer, Telecommunications and Information Technology (ECTI-CON) - Long-term Stability Analysis of Vertical Channel Damping and Kalman Filtering for Inertial Navigation System/Vertical Gauge