• 전기의세계
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• v.57 no.7
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• pp.36-43
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• 2008

• 전기의세계
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• v.54 no.8
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• pp.20-25
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• 2005

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1998.11a
• /
• pp.86-91
• /
• 1998

• Electrical & Electronic Materials
• /
• v.24 no.4
• /
• pp.32-42
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• 2011

• Proceedings of the KIEE Conference
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• 1982.07a
• /
• pp.133-134
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• 1982

• Proceedings of the KIEE Conference
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• 1973.08a
• /
• pp.122-123
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• 1973

• Proceedings of the KIEE Conference
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• 1973.08a
• /
• pp.129-131
• /
• 1973

• 전기의세계
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• v.61 no.4
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• pp.33-38
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• 2012

• Journal of the Korean Society for Railway
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• v.7 no.2
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• pp.12-17
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• 2004

철도 신호제어장치들은 각자 고유기능을 수행함으로써 철도시스템의 안전운행을 도모하고 있다. 따라서 대부분의 신호장치는 바이탈한 제어장치로서 안전측 동작(Fail-safe)을 보장하기 위하여 기존에는 기계적 또는 전기적인 계전기 로직에 의해 각 장치 고유의 기능을 수행하였다. 그러나 최근에 들어 전자, 컴퓨터, 통신 기술의 발달에 따라 철도신호제어장치들도 전자화된 장치들로 대체되어가고 있는 추세이다. 이처럼 신호제어장치들이 전자화되어감에 따라 각 장치간 인터페이스를 위한 링크도 디지털 통신채널로 대체되어가고 있다. 따라서 이러한 각 장치간 인터페이스를 위한 통신링크에 대한 중요성이 증대되고 있다. (중략)

• Journal of Biomedical Engineering Research
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• v.25 no.5
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• pp.343-349
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• 2004

Electroglottograph(EGG) is a signal recorded from the vocal cord vibration by measuring electrical impedance across the vocal folds through the neck skin. The purpose of this study was to develop EGG system and to evaluate possibility for the application on speech analysis and laryngeal disease diagnosis. EGG system was composed of two pairs of ring electrodes, tuned amplifier, phase sensitive detector, low pass filter, and auto-gain controller. It was designed to extract electric impedance after detecting by amplitude modulation method with 2.7MHz carrier signal. Extracted signals were transmitted through line-in of PC sound card, sampled and quantized. Closed Quotient(CQ), Speed Quotient(SQ), Speed Index(SI), fundamental frequency of vocal cord vibration(F0), pitch variability of vocal fold vibration (Jitter), and peak-to-peak amplitude variability of vocal fold vibration(Shimmer) were analyzed as EGG parameters. Experimental results were as follows: the faster vocal fold vibration, the higher values in CQ parameter and the lower values in SQ and SI parameters. EGG and speech signals had the same fundamental frequency. CQ, SQ, and SI were significantly different between normal subjects and patients with laryngeal cancer. These results suggest that it is possible to implement portable EGG system to monitor the function of vocal cord and to test functional changes of the glottis.