• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2000년도 하계종합학술대회 논문집(5)
• /
• pp.110-112
• /
• 2000

Recently, the interest and the importance of the signal monitoring and recording during sleep is increasing. Conventional paper based recording systems are being replaced by digital type and polysomnographic system. We developed special digital signal processor system for the polysomnographic recording. This system consists of digital signal processing part and PC interface part for user's convenience. This system includes two digital filters, one fur low pass filtering of high frequency noise and the other for notch filtering of 60Hz AC noise. This system can be used for the efficient and convenient measurement of polysomnographic signals and also can be developed for the portable use.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1998년도 추계학술대회 논문집 학회본부 C
• /
• pp.922-924
• /
• 1998

In this paper, an optical fiber sensor(OF sensor) utilizing the principal of Mach-Zehnder interferometer were proposed to detect the partial discharge signals in insulating oil. At first the AC breakdown signals were detected to check the response of the OF sensor. The detected signals from OF sensor was consistent with that from current probe. After the response checking, simultaneous measurements and continuous recording were made of electrical and the OF sensor signals from partial discharge(PD) produced by IEC(b) electrode system immersed in insulating oil. The continuous recording made it possible to extract basic quantities of PD from the OF sensor signals, such as pulse phase and pulse amplitude distribution. Through the signal analysis, the absolute peaks of the OF sensor PD signal was found to be increased with the amplitude of electrical signals, and these results mean that there is a strong correlation between OF sensor and electrical PD signals. It was demonstrated that the OF sensor in this research had a possibility to detect the PD signals in power apparatus.

• 대한전자공학회논문지SD
• /
• 제47권1호
• /
• pp.60-68
• /
• 2010

청신경의 이상으로 발생하는 감각신경성 난청의 경우, 달팽이관이나 청각신경에 전극을 이식하여 전기자극을 가함으로써 청지각을 살릴 수 있다. 이를 위해 우선적으로, 각 청각신경들이 담당하여 인지할 수 있는 소리의 주파수 분포를 표시한 음계소지도를 파악해야 한다. 본 논문에서는 청각신경신호 검출 장치용 다중채널 아나로그 프론트엔드 회로를 제안한다. 제안된 아나로그 프론트엔드의 각 채널은 AC 커플링 회로, 저 전력 4차 Gm-C LPF와 단일 기울기 ADC로 이루어진다. AC 커플링 회로는 청각신호의 불확실한 DC 전압 레벨을 제거하고 AC 신호만 전달한다. Gm-C LPF는 청각신호의 대역폭을 고려하여 설계 되었으며, 플로팅-게이트 기법이 적용된 OTA를 사용하였다. 채널별 ADC를 구현하기 위해서, 최소의 면적으로 구현할 수 있는 단일 기울기 ADC 구조를 사용하였다. 측정 결과, AC 커플링 회로와 4차 Gm-C LPF는 100 Hz - 6.95 kHz의 대역폭을 가지며, 단일 기울기 ADC는 7.7 비트의 유효 해상도를 가진다. 그리고, 채널 당 $12\;{\mu}W$의 전력이 소모 되었다. 전원 전압은 3.0 V가 공급되었고, 코어는 $2.6\;mm\;{\times}\;3.7\;mm$의 실리콘 면적을 차지한다. 제안된 아나로그 프론트엔드는 1-poly 4-metal $0.35-{\mu}m$ CMOS 공정에서 제작 되었다.

• 한국응용곤충학회지
• /
• 제33권1호
• /
• pp.19-25
• /
• 1994

식물휘발성 물질에 대한 벼멸구 촉각의 반응을 전기 생리학적인 반응을 관찰하였다. 식물휘발성 물질은 일반적으로 곤충이 그들의 먹이나 산란 장소를 찾는데 아주 중요한 요소로 작용하고 있다. 이러한 기주 특이적인 성질을 파악하기 위하여 벼멸구 촉각에 분포하고 있는 화학감각기의 반응을 AC반응을 통하여 기록하였다. 벼멸구의 plaque organ에서 기된 spike 의 모양은 positive-going biphasic형으로 background spike는 초당 1~22개로 다양하였다. 벼멸구 촉각은 실험한 화학물질들에 광범위하게 반응하고 있는 것을 보여주었으며 농도가 높아짐에 따라 더욱 흥분되지만 일정 수준이상의 농도에서는 더 이상 흥분되지 않거나 억제되는 것을 보여주었다. 본 실험에서는 검정된 대부분의 식물 휘발성물질에서 가장 큰 반응을 보인 농도는 단위 용기 안에 100$\mug$의 물질이 있을 때였고, 가장 큰 반응을 보인 화합물은 hexanal 과 acetophenone이었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제4권1호
• /
• pp.91-97
• /
• 1991

Twenty five 75% Holstein Friesian cross bred bullocks fed rice straw (Oryza sativa) of long form, were fed with the following five treatments. 1. Rice straw, untreated (RS) 2. RS + water (1:1), stored for 24 hours (WRS) 3. RS (100 kg) + urea solution (4 kg urea/100 litre water) and dried (USRS) 4. RS (100 kg) + urea solution (as in 3) stored in wet condition for 24 hours (UWRS) 5. RS (100 kg) + urea solution (as in 3) stored in pit for 21 days (UTRS). Potential digestibility of treatments of RS was evaluated by monitoring (in vitro) Simulating Rumen like Fermentation (SRLF). The results indicated that Dry Matter Intake (DMI), digestibility of nutrients, N utilization were of the order UTRS > UWRS > USRS > WRS and RS (p < 0.05 to p < 0.01). SRLF index was high (255.84) for UTRS and least (145.58) for USRS. It was intermediary (199.66) for UWRS. The acetyl content (AC) of UTRS with higher hemicellulose (HCE) digestibility (80.8%) was low compared to UWRS, USRS, RS and WRS. The acetate content was of the order UTRS < UWRS < USRS < WRS and RS thereby indicating that reduction in acetyl content was an index of positive response of urea-treatment of RS. In addition, the ratio of HCE/AC in faeces of UTRS was 0.87 as against the ratios (2.26-2.48) observed in other treatments recording reduction in AC due to urea-treatment. Among the treatments, USRS only supplemented N while UTRS in addition to utilization N, increased the digestibility of structural carbohydrates. Reduction in treatment time from 21 days to 1 day (UWRS) resulted in improvements similar to those of UTRS.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2002년도 추계학술대회논문집
• /
• pp.1000-1003
• /
• 2002

For high density optical storage, there should be a high NA objective lens and a shorter wavelength laser diode. To secure the disc tilt margin related to the coma aberration, moreover, it's difficult to apply the tilt compensation mechanism into the portable PC. In this paper, we proposed the 3-axis asymmetry pickup actuator with high efficiency symmetric magnetic circuit, which consisted of the top cover type inner yoke for high magnetic flux density, the coil stack unit for the 3-axis independent operation and vertically polarized magnets. This newly suggested actuator features DVD-RAM recording, we achieved the high focus & track AC sensitivity and the greatly stabilized system.

• 한국소음진동공학회:학술대회논문집
• /
• 한국소음진동공학회 2002년도 춘계학술대회논문집
• /
• pp.378-380
• /
• 2002

There has been lower the tilt margin by the increase of coma aberration due to the reduction of wave-length and the increase of numerical aperture for high density recording. The RF signal degradation is increased as the decrease of tilt margin. To compensate the tilt margin, the optical pick-up actuator for high-speed CD/DVD re-writable system should be able to drive the radial-tilt motion. We announce that the 3-axis drive actuator for high-speed CD/DVD rewritable system. And what was more, the DC/AC sensitivities of this actuator are suitable fur the low-speed playability, the high-speed readability and the high-speed rewritability.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1995년도 하계학술대회 논문집 B
• /
• pp.754-757
• /
• 1995

This system can detect a ground fault point or a bad insulated line by measuring a power plant DC feeder insulation resistance at the uninterruptible power status. And when the power plant DC feeder with low frequency AC signal has a ground fault, this measuring system can keep recording of its ground fault current and phase checked by Z.C.T. Therefore the power plant could protect a unexpected service interruption.

• 천문학회보
• /
• 제43권2호
• /
• pp.46.1-46.1
• /
• 2018

The Fast Imaging Solar Spectrograph (FISS) on the Goode Solar Telescope (GST) at Big Bear Solar Observatory is the imaging Echelle spectrograph developed by the Solar Astronomy Group of Seoul National University and the Solar and Space Weather Group of Korea Astronomy and Space Science Institute. The instrument takes spectral data from a region on the Sun in two spectral bands simultaneously. The imaging is done by the organization of intensity data obtained from the fast raster scan of the slit over the field of view. Since the scan repeats many times, the whole set of data can be used to construct the movies of monochromatic intensity at arbitrary wavelengths within the spectral bands, and those of line-of-sight velocity inferred from different spectral lines. So far there are two standard observing configurations: one recording the $H{\alpha}$ line and the Ca II 8542 line simultaneously, and the other recording the Na I D2 line and Fe I 5435 line simultaneously. We have developed the procedures to produce the standard data for each observing configuration. The procedures include the spatial alignment, the correction of spectral shift of instrumental origin, and the lambdameter measurement of the line wavelength. The standard data include the movie of continuum intensity, the movies of intensity and velocity inferred from a chromospheric spectral line, the movies of intensity and velocity inferred from a photospheric line. The processed standard data will be freely available online (fiss.snu.ac.kr) to be used for research and public outreach. Moreover, the IDL procedures will be provided on request as well so that each researcher can adapt the programs for their own research.

• 한국응용곤충학회지
• /
• 제60권4호
• /
• pp.363-367
• /
• 2021

본 연구는 성페로몬에 대한 열대거세미나방 수컷 성충의 촉각 반응 및 중복 교미 여부를 확인하기 위해 수행하였다. 성페로몬 성분인 Z9-14:Ac에 대한 열대거세미나방 수컷 성충의 촉각 반응은 농도 의존적으로 농도가 증가할수록 크게 나타났다. 조사한 7성분 중 Z9-14:Ac 성분에 대한 촉각 반응이 가장 컸다. 성페로몬의 혼합 성분에 대한 촉각 반응이 단일 성분에 비해 컸다. 열대거세미나방 수컷 성충은 실험실 조건에서 중복교미가 가능하고, 첫 교미율이 58.3%인데 비해서 두 번째 교미율이 72.2%로 증가하였다. 교미한 수컷 성충의 촉각 반응과 교미하지 않은 수컷 성충의 촉각 반응의 차이가 없었다. 성페로몬 트랩에 교미하지 않은 수컷이 시험기간 중에 포획되지 않았다. 대조구인 교미하지 않은 암컷 성충을 장착한 트랩에서도 교미하지 않은 수컷 성충은 포획되지 않았다. 비록 실내에서 교미한 수컷 성충은 성페로몬 성분에 대해 교미하지 않은 수컷 성충처럼 촉각 반응을 보였다고 할지라도 실제 야외 망실 하우스에서 교미를 한번 한 수컷 성충은 비행 능력 등 활력의 문제로 트랩에 포획되지 않았을 가능성이 있다고 생각된다. 야외 노지에서 열대거세미나방 성페로몬에 대한 수컷 성충의 유인 정도는 추후 좀 더 많은 검토가 필요할 것으로 본다.