• Korean Journal of Remote Sensing
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• v.31 no.3
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• pp.227-244
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• 2015

Synthetic Aperture Radar is able to provide images of wide coverage in day, night, and all-weather conditions. Recently, as the SAR image resolution improves up to the sub-meter level, their applications are rapidly expanding accordingly. Especially there is a growing interest in the use of geographic information of high resolution SAR images and the change detection will be one of the most important technique for their applications. In this paper, an automatic threshold tracking and change detection algorithm is proposed applicable to high-resolution SAR images. To detect changes within SAR image, a reference image is generated using log-ratio operator and its amplitude distribution is estimated through K-S test. Assuming SAR image has a non-gaussian amplitude distribution, a generalized thresholding technique is applied using Kittler and Illingworth minimum-error estimation. Also, MoLC parametric estimation method is adopted to improve the algorithm performance on rough ground target. The implemented algorithm is tested and verified on the simulated SAR raw data. Then, it is applied to the spaceborne high-resolution SAR images taken by Cosmo-Skymed and KOMPSAT-5 and the performances are analyzed and compared.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.10a
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• pp.23-23
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• 1993

• TTA Journal
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• s.141
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• pp.74-79
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• 2012

• Aerospace Engineering and Technology
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• v.1 no.1
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• pp.188-200
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• 2002

• Journal of Advanced Navigation Technology
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• v.5 no.1
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• pp.74-84
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• 2001

Recently a new algorithm which combines advantages of the IMM and IE methods has been suggested. The combined-IMM/IE algorithm could improve the performance to some extent. However, the problem of large increase of tracking error near the maneuver detection due to the sudden maneuver input has not been solved. In this paper, we propose two schemes which can resolve this limitations of combined-IMM/IE algorithm. For illustrations of the performance of the proposed methods. Monte-Carlo simulations are carried out and the results are analyzed.

• Journal of Institute of Control, Robotics and Systems
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• v.19 no.8
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• pp.731-737
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• 2013

In this paper, we propose an image-based output feedback robust controller of robot manipulators which have bounded parametric uncertainty. The proposed controller contains an integral action and high-gain observer in order to improve steady state error of joint position and performance deterioration due to measurement errors of joint velocity. The stability of the closed-loop system is proved by Lyapunov approach. The performance of the proposed method is demonstrated by simulations on a 5-link robot manipulators with two degrees of freedom.

• Journal of the Korea Society of Computer and Information
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• v.23 no.8
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• pp.101-106
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• 2018

Most people with visual impairments can not use both hands freely because they carry a cane. And unnecessary contact with people around you during walking can occur. Other guides include guide dogs, but the price and maintenance cost are expensive and difficult to manage. In this paper, we propose a smart glove, which prevents unnecessary contact when blind people use the cane, detects the obstacle ahead by using the ultrasonic sensor, and informs the presence of the obstacle by using the servo motor. In addition, the electrostatic proximity touch module on the fingers executes a specific application of the smart phone connected by Bluetooth when the finger touches each other. It is designed to allow you to use text or phone calls when you are lost or in an emergency. The results of this study will be used as a tool to provide a more convenient life for the visually impaired.

• Journal of the Korea Society of Computer and Information
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• v.23 no.8
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• pp.17-23
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• 2018

In this paper, we implemented a flight posture simulator that intuitively understands aircraft flight posture and visualizes the principle of motion. The proposed system operates the 6 - axis motion platform according to the change of the navigation information and transmits the flight attitude to the simulator using the gyro sensor. A gyro sensor and an acceleration sensor are used together to analyze the attitude of the aircraft. The reason is that the gyro sensor has a cumulative error in the integration process. And the accelerometer sensor was compensated by using the complementary filter because noise was serious due to short term vibration. Using the compensated sensor information, the motion platform is operated by calculating the angle to be transmitted to the 6-axis motor. And visualization result is implemented using OpenGL. The results of this study can be used as teaching materials for students related to aviation in the future.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.4
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• pp.1116-1124
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• 1995

Using a cycle simulation program developed by authors, some thermodynamic characteristics of an aircraft ECS under various operating conditions are studied. When the inlet temperature of cockpit and avionics bay, as well as ram air flow, is held fixed, the effect of the change of regulated bleed pressure is examined. When the regulated bleed pressure, and the cockpit and avionics bay inlet temperature are fixed, the effect of the change of ram air flow is also investigated.

• Journal of Electrical Engineering and Technology
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• v.7 no.5
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• pp.789-796
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• 2012

Fingerprinting is a widely used positioning technology for received signal strength (RSS) based wireless local area network (WLAN) positioning system. Though spatial RSS variation is the key factor of the positioning technology, temporal RSS variation needs to be considered for more accuracy. To deal with the spatial and temporal RSS characteristics within a unified framework, this paper proposes an extended signal propagation mode (ESPM) and a fingerprint generation method. The proposed spatiotemporal fingerprint generation method consists of two algorithms running in parallel; Kalman filtering at several measurement-sampling locations and Kriging to generate location fingerprints at dense reference locations. The two different algorithms are connected by the extended signal propagation model which describes the spatial and temporal measurement characteristics in one frame. An experiment demonstrates that the proposed method provides an improved positioning accuracy.