• 전기학회논문지
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• 제57권7호
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• pp.1195-1199
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• 2008

In this paper, peak detector of generator's output voltage and variable gain controller are introduced for a fast dynamic response. The conventional r,m.s, signal detected has inherent time delay, and the dynamic response of generator using conventional PID controller has some problem in sudden load change. In this paper, the peak detector and signal selector with variable gain controller is used to overcome this problem. The main controller can check the voltage state from the peak detector. When a sudden load change, the over-voltage and under-voltage signal from peak detector change the controller's gain and exciter's current reference. The proposed scheme can improve the dynamic response, which is verified from experimental test of 200kW diesel engine-generator.

• Journal of Oral Medicine and Pain
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• 제36권2호
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• pp.107-115
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• 2011

교합이 완성된 성인에서 비정복성 관절원판전위가 있는 경우에 과두흡수가 없는 상태에서도 갑작스런 교합의 변화 즉 전치부 개교합이 발생한 환자 2명과 측방으로 중심위와 중심교합위 간 활주가 발생한 환자 1명과 그리고 전후방으로 중심위와 중심교합위 간의 차이가 발생한 1명의 환자를 관찰하였기에 증례 보고하는 바이며, 비정복성 관절원판전위와 연관되어 교합의 변화가 발생하는 원인을 분석하고자 한다.

• 한방안이비인후피부과학회지
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• 제28권3호
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• pp.145-160
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• 2015

Objective : The purpose of this study was to report a significant improvement of Tinnitus with Sudden sensorineural hearing loss(SSHL) after treatment with Daehamhyung-tang.Methods : We experienced four cases of tinnitus with SSHL treated by Daehamhyung-tang. To evaluate the results of this treatment, we used the visual analogue scale(VAS)Results : After using Daehamhyung-tang, VAS and clinical symptoms of 3 patients were improved remarkably, but 1 case was no interval change.Conclusion : This study suggests that using Daehamhyung-tang is effective on tinnitus with SSHL.

• 한국자동차공학회논문집
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• 제15권1호
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• pp.71-77
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• 2007

Dangerous driving is a major cause of traffic accidents in Korea. It becomes more serious for commercial vehicles due to higher fatality rates. The Safe Driving Management System (SDMS), developed in this research, is a comprehensive solution that monitors and stores driving conditions of vehicles, detects dangerous driving situations, and analyzes the results in real time. The Safe Driving Management System consists of a vehicle movement information controller, a dangerous driving detection algorithm and a vehicle movement data report and analysis program. The dangerous driving detection algorithm detects and classifies dangerous driving conditions into representative cases such as sudden acceleration, sudden braking, sudden lane change, and sudden turning. Both computer simulation and vehicle test have been conducted to develop and verify the algorithm. The Safe Driving Management System has been implemented on commercial buses to verify its reliability and objectivity. It is expected that the system can contribute to prevention of traffic accidents, systemization of safe driving management and reduction of commercial vehicle operation costs.

• 한국진공학회지
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• 제20권1호
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• pp.1-6
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• 2011

포항광가속기의 섹터 진공용기에 부착된 빔위치측정기의 수직방향 위치 읽음 값이 갑자기 변하는 오류가 관찰되었다. 이 오류의 원인을 알기 위해서 섹터 진공용기의 양 끝단에 있는 빔위치측정기의 전극을 통한 고주파전달 산란계수를 측정하였다. 급한 변화를 보이는 섹터 진공용기에서는 측정한 산란계수의 첨단 값이 빔위치측정기의 작동 주파수 내에 존재함을 확인하였고, 전산시늉을 통해 빔위치측정기의 작동 주파수내 첨단 주파수가 가로 전장 모드의 공진모드와 일치함을 확인하였다.

• 한국환경과학회지
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• 제26권4호
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• pp.543-547
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• 2017

Normalized Difference Vegetation Index (NDVI) has played an important role in assessing green plant biomass through remote sensing on global scale since the early 1970s. The concept of NDVI is based on the fact that green plants show higher reflection in near-infrared region than in visible region of the electromagnetic spectrum. However, it is well known that the relocation of chloroplasts in plant leaf cells may dramatically change the optical properties of plant leaves. In this study I traced the changes in the reflectance and transmittance properties of Tobacco leaves at the wavelengths of 660 and 800 nm after a sudden increase in light intensity. The results showed that NDVI of leaves gradually decreased from 72.7% to 69.9% when exposed to a sudden increase in light intensity from 30 to $1,200{\mu}mol/m^2{\cdot}s$. This means that the error resulting from the physiological status of the plant should be accounted for a more precise understanding of ground truth corresponding to the data from the remotely acquired images.

• Journal of Advanced Marine Engineering and Technology
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• 제35권4호
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• pp.468-474
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• 2011

급확대 축소 채널에 설치된 배플 주위의 유동장을 PIV기법으로 계측하고, 배플의 높이 변화에 따른 영향을 평가하였다. 유입유속과 배플 높이는 배플 후방의 재순환흐름에 크기와 유동패턴 및 배플의 상부를 지나는 수력점프 영역의 크기에 상호 영향을 준다. 레이놀즈수 $Re=4{\times}10^3$의 경우 유입유속의 증가에도 유속이 낮아지는 배플의 임계높이는 h/H=1.6전후로 추정된다.

• 한국환경과학회지
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• 제24권7호
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• pp.883-892
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• 2015

The study investigates the characteristics of $PM_{10}$ concentration in Guducsan air quality observatory and in particular, analyzes the relationship between sudden increase of $PM_{10}$ concentration in the morning of spring 2014 and meteorological parameters. $PM_{10}$ concentration in April was $46.9{\mu}g/m^3$, the highest, followed by $45.5{\mu}g/m^3$ and $44.6{\mu}g/m^3$ in March and May, and $21.9{\mu}g/m^3$ in August. The low concentration in the early morning appeared on 0800 LST in spring, summer, and fall, whereas it emerged on 0900 LST in winter. High concentration in daytime lasted from 1200 LST to 1500 LST in spring and fall, whereas it continued from 1300 LST to 1600 LST in winter. The findings of $PM_{10}$ concentration and change of meteorological parameters in Guducsan from April 20th to 27th in 2014 are as follows. The low concentration at dawn and in the morning decreased due to strong land breeze. Also, the sudden increase of $PM_{10}$ concentration in the morning was attributable to low wind speed. Lastly, the sudden decrease of $PM_{10}$ concentration in the afternoon was attributed to diffusion by strong sea breeze.

• 대기
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• 제25권3호
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• pp.461-472
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• 2015

The sudden stratospheric warming (SSW), which is characterized by an abrupt increase of polar stratospheric temperature by several tens of degrees in a week, has been known to affect tropospheric weather and climate on sub-seasonal time scale in the boreal winter. Such downward coupling has been often examined in North Atlantic and Europe, but rarely examined in East Asia. In this study, by applying the two definitions of SSW to the reanalysis data, the possible impacts of the SSW events on the surface air temperature (SAT) and tropospheric circulation in East Asia are analyzed. It is found that Eurasian continent, including Siberia and the Northeast Asia, tends to experience anomalously cold SAT for up to sixty days after the SSW events. The resulting SAT anomalies largely resemble those associated with negative Artic Oscillation. However, over East Asia, SSW-related SAT change is weak and not statistically significant. Only during the extreme SSW events when the downward coupling between the stratosphere and troposphere is strong, East Asia exhibits significantly cold SAT anomalies. This relationship is presented by grouping SSW events into those followed by cold SAT anomalies over East Asia and those by warm anomalies for varying threshold values of the SSW events.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1979년도 하계 전자.전기연합학술발표회논문집
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• pp.153-154
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• 1979