• 수산해양기술연구
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• 제22권3호
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• pp.23-28
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• 1986

This paper describes on the measurement of the deck vibration produced by the main engine vibration of stern trawler MjS SAE-BA-DA (2,275GT, 3,600PS) while the ship is cruising and drifting. The obtained results are as follows; 1. The deck vibration level was the highest point at vertical line which pass main engine and the lowest point at vertical line which pass top bridge while the crusing. 2. The vibration source level of the main engine, screw shaft and screw propeller were respectively 110, 90 and 80% while the crusing. 3. The main deck vibration pressure level at the check points 2, 20, 30, 40, 60, 70, 80, 86m from the bow to stern was respectively 9, 8, 7, 10, 22, 45, 18, 23%. 4. The frequency distributions of the rr.ain engine, screw shaft, screw propeller vibration were from 3 Hz to 10 KHz, predominant frequency was 1 KHz, each vibration accelration the highest level were respectively 1. 3, 0.8, 0.5 $mm/s^2.$ 5. The predominant frequency distributions of the main deck, second deck, bridge deck and top bridge deck-s vibration were from 10 to 30 Hz, and each vibration accelration level were respectively 0.7, 0.05, 0.07, 0.04 $mm/s^2.$

• 어선
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• 제29권
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• pp.15-20
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• 1986

This paper describes on the measurement of the deck vibration produced by the main engine vibration of stern trawler MIS SAE-BA-DA (2,275GT, 3,600PS) while the ship is cruising and drifting. The obtained results are as follows; 1. The deck vibration level was the highest point at vertical line which pass main engine and the lowest point at vertical line which pass top bridge while the crusing. 2. The vibration source level of the main engine, screw shaft and screw propeller were respectively 110, 90 and 80% while the crusing. 3. The main deck vibration pressure level at the check points 2, 20, 30, 40, 60, 70, 80, 86m from the bow to stern was respectively 9, 8, 7, 10, 22, 45, 18, 23%. 4. The frequency distributions of the main engine, screw shaft, screw propeller vibration were from 3Hz to 10KHz, predominant frequency was 1KHz, each vibration accelration the highest level were respectively 1.3, 0.8, 0.5mm/$S^2$. 5. The predominant frequency distributions of the main deck, second deck, bridge deck and top bridge deck's vibration were from 10 to 30Hz, and each vibration accelration level were respe¬ctively 0.7, 0.05, 0.07, 0.04mm/$S^2$.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.771-776
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• 2010

Since the importance of seismic design is greater, dynamic analysis is more widely using than past. The input motion is one of the most important factors of dynamic analysis. However, in Korea input motions are selected from U.S. and Japan those are captured from large magnitude earthquakes without considering seismic environment or generated in frequency domain. In this research, the methodology for generating input motions those are considered seismic environment and design code is proposed. The seismic environment compatibility is considered by performing deaggregation and the design code compatibility is considered by time-domain artificial time history accelration generation method. The results shows that seismic environment and design code compatible input motions are successfully generated.

• Nuclear Engineering and Technology
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• 제38권2호
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• pp.195-200
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• 2006

In order to confirm the integrity of IRWST following a severe accident, the hydrogen behavior inside and around the IRWST has been investigated for an SBO accident. A detailed containment model, including 18 control volumes for IRWST, has been developed. Analysis results show that the peak hydrogen concentration is about 57% during the core melting period. The combustion regime shows that flame acceleration and DDT are possible in the IRWST. The flame acceleration criterion is met when the peak hydrogen concentration occurs; the 7 -DDT criterion is also met during some periods. These results show certain measures may be required to assure IRWST integrity against an SBO accident.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.52-57
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• 1998

Becaruse of the continual occurrence of minor and moderate earthquake in Korean peninsula, it is generally considered that Korean is nor located in safe region against probable earthquake and more, even though being recognized as a safe contry in earthquake. It is in particular noted that nowadays there has been much concern about undesirable disaster due to unexpected earthquake since the disaster of 1995 Kobe earthquake. Thus, the objective of this research is to develop appropriate design spectrum which could be practicably used in seismic design of important structures taking into consideration of local physical characteristics. Particularly, we have to keep in mind the lessons from 1985 Mexico earthquake which had disregarded deep research on local ground conditions, being a possible magnification phenomena of ground motions in weak soil layer. Various spectra has been described based on the analysis of historical earthquakes, and appropriate design spectrum has been proposed herein.

• 한국추진공학회지
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• 제23권5호
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• pp.43-52
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• 2019

극저온 유체를 사용하는 발사체는 극저온 유체의 자연순환회로를 이용하여 발사체의 엔진 입구를 냉각한다. 자연순환회로의 질량유량은 순환시스템을 구성하는 배관의 길이 및 직경과 시스템으로 들어오는 열유입에 의하여 결정된다. 극저온 유체의 자연순환회로의 순환 검증 및 질량유량 측정을 위하여 실험을 진행하였으며, 이론적 계산 결과와 비교하였다. 비교 결과 12%의 오차가 있음을 확인하였다. 이 결과를 바탕으로 발사체 상단에서 저중력 구간 및 가속 구간에서의 자연순환 질량유량을 예측한 내용을 포함한다. 가속구간에서는 산화제탱크가 100 kPa 내외로 유지하는 것이 자연순환유량 증가에 이로웠으며, 저중력구간에서는 중력가속도의 크기에 따른 최적 압력으로 조절해야 자연순환유량의 최고값을 유지할 수 있었다.