• Journal of Biomedical Engineering Research
• /
• v.16 no.3
• /
• pp.301-308
• /
• 1995

A high-precision pre-amplifier is designed for general use in EEG measurement system. It consists of signal generator, signal amplifier with a impedance converter, shield driver, body driver, differential amplifier, and isolation amplifier. The combination of minimum use of inaccurate passive components and the appropriate matching of each monolithic amplifiers results in good noise behavior, low leakage current, high CMRR, high input impedance, and high IMRR. The performance of EEG pre-amplifier has been verified by showing the typical EEG pattevn of a nomad person through the clinical experiments.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2000.11a
• /
• pp.409-412
• /
• 2000

A high performance EEG signal measurement system is fabricated. It consists of high precision pre-amplifier and auto identification bandwidth unit. High precision pre-amplifier is composed of signal generator, signal amplifier with a impedance converter, body driver and isolation amplifier. The pre-amplifier is designed for low noise characteristics, high CMRR, high input impedance, high IMRR and safety, Auto identification bandwidth unit is composed of AD-converter and PIC micro-controller for real time processing EEG signal. The performance of EEG signal measurement system has been shown the classified bandwidth through the clinical demonstrations.

• Progress in Medical Physics
• /
• v.13 no.3
• /
• pp.156-162
• /
• 2002

In this study, we attempted in preparing high precision EEG measuring equipment. To measure EEG in high efficiency, pre-amplifier should get high performance common mode rejection ratio. Also, separation amplifier is essential to eliminate common line noise. So, our study were pointed at elevating the efficiency of eliminating noise, user safety and low noise characteristics. Prepared high precision pre-amplifier for EEG was A/D converted to automatically classify $\alpha$ wave, $\beta$ wave and $\theta$ wave. And converted data were Fast Fourier Transformed with real time DSP (Digital Signal Processing). Clinical demonstrations were carried out with healthy students, aged between 20 to 26 who has no histories of illness. To recognize the efficiency of the EEG, prepared EEG were used with MS equipment in low stimulated state and high stimulated state. Then, we studied at the effect of sensitivity on brain wave. From this study, it is known that our EEG equipment is efficient in sensitivity evaluation and suitable stimulations for each psychological state are required.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.39 no.6
• /
• pp.517-525
• /
• 2011

Differential Vibrating Accelerometer(DVA) is a small and accurate resonant device to sense the change in natural frequency in presence of acceleration input. Both mathematical modeling for the electromechanical dynamics and experimental investigation on the structural characteristics are necessary for effective designs of precision controller and high Q-factor structure. In this paper, electromechanical modeling of the resonator of DVA, electrode module, and pre-amplifier is presented. The presented method is experimentally verified by measuring the resonance frequency, effective mass, effective stiffness and Q-factor. The direct comparison of the calculated displacement and the actual pre-amplifier of DVA also indicates the effectiveness of this study.

• Proceedings of the KIEE Conference
• /
• 2008.07a
• /
• pp.1743-1744
• /
• 2008

NSOM(Near-field Scanning Optical Microscopy) 조화 진동자(Tuning fork)와 광섬유 탐침을 결속시켜 미소신호를 검출하여 증폭과 잡음을 제거하기 위한 Pre-amplifier의 설계 및 제작과 더불어 시료-탐침간 거리를 파장보다 짧게 유지시키는 Shear force 검출, 효율적인 시료-탐침 거리유지 알고리즘 구연 및 탐침을 시료 표면에서 일정한 거리를 안정적으로 유지하도록 제어 및 시료의 높이 정보를 얻어내는 시스템을 설계 및 제작하였다. 또한 ����$CO_2Laser$를 이용한 Heat Pulling 장치개발을 통해 탐침을 제작, LabVIEW를 통해 개별적인 시스템을 하나로 통합하여 AFM 테스트 시료인 SiO 샘플의 표면 형상을 측정하였다.