• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.5 s.120
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• pp.553-562
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• 2007

In this paper, we designed and implemented the system for telemetering ELF(Extremely Low Frequency) magnetic field intensity. The magnetic field measurement system used a 3-axis magnetic field sensor to measure the magnetic field with isotropy and the equalizer to compensate the frequency characteristic in band. By multiplexing three output signals of the magnetic field sensor in time domain, we got the uniform gain and frequency characteristic among three axes. This system was designed that the magnetic field measurement level range was $0.01{\sim}10.0\;uT$ and the measurement frequency band was $40{\sim}180\;Hz$. The control system would access to the magnetic field measurement system with RF and the maximum access distance was 1.0 km. We confirmed that the measurement level error of the fabricated system was within 5 %. The fabricated system was installed to a golf practice range where a high voltage power transmission line was crossed.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.289-290
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• 2021

Recently, with the advent of the 4th industrial revolution, the role of robots is increasing, and the use of robots is also increasing in the service field. The most popular model for nonlinear research related to robots is the inverted pendulum system. A balancing robot using an inverted pendulum system is a representative nonlinear system and is mainly used to study control theory and other kinematic structures. In this paper, the state of the robot is measured using the 3-axis acceleration sensor (ADXL345) and 3-axis digital output gyro sensor (ITG-3200) or HMC5883L required for balancing robot control, and using the ESP32-WROOM-32 module. I want to design an MCU module that can control a balancing robot. In addition, by using the ESP32-WROOM-32 MCU module, we intend to design an MCU module that can monitor the state of the balancing robot based on WiFi or Bluetooth.

• Journal of Advanced Navigation Technology
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• v.13 no.2
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• pp.262-271
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• 2009

The purpose of this study was to propose the method to recognize gestures based on inertia sensor which recognizes the movements of the user using inertia sensor and lets the user enjoy the game by comparing the recognized movements with the pre-defined movements for the game contents production. Additionally, it was tried to provide users with various data entry methods by letting them wear small controllers using three-axis accelerator sensor. Users can proceed the game by moving according to the action list printed on the screen. They can proceed the experiential games according to the accuracy and timing of their movements. If they use multiple small wireless controllers together wearing them on the major parts of hands and feet and utilize the proposed methods, they will be more interested in the game and be absorbed in it.

• Proceedings of the KSRS Conference
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• 2008.03a
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• pp.53-58
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• 2008

인공위성을 통해 취득된 데이터들은 지상국의 수신처리시스템을 거쳐 표준영상으로 생산되며, 생산된 영상으로부터 사용자에게 의미 있고, 가치 있는 정보를 이끌어 내는 판독의 단계를 수행하게 된다. 본 연구에서는 원격탐사의 전반적인 이해를 돕기 위한 교육적 모델로서 캔샛 프로그램을 도입하였다. 캔샛 프로그램은 스탠포드대 로버트 트윙 교수의 제안으로 학생들에게 한 학기의 짧은 시간에 실제 인공위성의 설계, 해석, 제작, 조립, 시험, 발사, 운용 등 전반적인 시스템의 이해를 도모하기 위한 1Kg 이하의 캔 크기의 초소형 위성을 개발하는 교육 프로그램이다. 본 연구는 한국과학영재학교 R&E 프로그램의 지원으로 시작하였으며, 실제 초소형 위성 캔샛('KSAsat'으로 명명)을 직접 설계, 제작, 조립하고 최종적으로 발사 운용 시험을 수행하였다. 주 탑재체로 일반 상용 디지털 카메라를 장착하였으며, GPS, 광센서, 3 축 가속도계, 온도센서, 압력센서를 탑재하였다. 비행시험을 통해 성공적으로 영상을 취득하고, 각종 센서로부터의 데이터를 지상국으로 전송 받았다. 지상국을 통해 처리 되어진 데이터로부터 의미 있는 정보를 추출하는 판단의 단계를 거쳐 원격탐사의 전반적인 교육을 성공적으로 수행할 수 있었다. 본 논문에서 캔샛 프로그램이 원격탐사 교육에도 충분히 활용될 수 있음을 보였다.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2009.05a
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• pp.360-364
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• 2009

현대사회는 인구의 고령화에 따른 노인인구의 증가 및 만성질환자의 증가에 따른 의료수요 급증이 예상되고 있다. 하지만 현재의 의료서비스 인프라는 증가하는 의료수요를 충족하기에는 역부족이 따르며, 이러한 문제점을 해결하기위해 정보통신기술과 헬스케어기술이 결합된 유비쿼터스 헬스케어기술이 부각되고 있다. 본 연구에서는 일상생활 중 움직임에 따른 활동 상태를 판별하여 운동량의 모니터링을 통한 건강관리뿐만 아니라 낙상 등과 같은 응급상황의 모니터링이 가능한 시스템을 구현하고자 하였다. 이를 위하여 3축 가속도센서를 이용하여 인체의 움직임에 따른 활동 가속도 신호를 계측할 수 있는 센서 및 시스템을 구현하였다. 또한 계측된 센서신호를 PC또는 휴대용 단말기로 무선전송하기위하여 무선센서네트워크 기술을 적용한 데이터 전송시스템을 구현하였다. 계측된 가속도 신호로부터 활동 상태를 판별하기위해 다층 퍼셉트론 알고리즘을 적용한 분류알고리즘을 제안하였으며, 분류알고리즘의 성능평가를 통해 실제 활동상태 모니터링에 적용 가능함을 확인하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.3
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• pp.770-776
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• 2021

Positioning systems have been actively researched and developed over the past few years and have been used in many applications. This paper presents a method to determine a location in a large space using a sensor system consisting of an accelerometer and a single-axis gyroscope. In particular, to consider usability, a sensor device was loosely worn on the waist so that the experimental data could be used in practical applications. Based on the experimental results of circular tracks with radiuses of 1m and 3m, in this paper, an algorithm using the threshold of rotation angle was proposed and applied to the experimental results. A tracking experiment was performed on the grid-pattern track model. For raw sensor data, the average deviation between the final tracking point and the target point was approximately 15.2 m, which could be reduced to approximately 4.0 m using an algorithm applying the rotation angle threshold.

• Journal of the Korean Magnetics Society
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• v.23 no.1
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• pp.18-25
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• 2013

MFL PIG (Magnetic Flux Leakage Pipeline Inspection Gauge) is called the system which detects the defect for underground pipelines by using magnetic flux leakage method in nondestructive testing. This method is very suitable for testing pipelines because pipeline has high magnetic permeability. MFL PIG generates the magnetic fields to the pipe axially oriented, and detect the signal of leakage flux by using hall sensor. However, MFL PIG is hard to detect the axially oriented crack with small size because the magnetic flux leakage is not enough to be occurred. To detect the small size and axially oriented crack, the circumferential MFL (CMFL) PIG is being proposed and it can maximize the leakage flux for the axial crack by performing magnetic fields circumferentially on the pipe. In this paper, CMFL PIG is applied to detect the axially oriented crack with small size and the analysis for the distribution and the amplitude of the leakage flux signal is performed by using three dimensional finite element method. From sensing signals, the method how to determine the shape of axially oriented cracks is proposed and verified with experiment.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.759-760
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1013-1014
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• 2010

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.1015-1016
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• 2010