• Journal of Astronomy and Space Sciences
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• v.22 no.2
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• pp.125-138
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• 2005

S152 is a small bright emission nebula located in the Perseus arm. Its optical diameter corresponds to 1.5 pc for an adopted distance 3.5 kpc. However, S152 is a part of a giant molecular cloud complex, which consists of several dense cores, containing active star-forming sites, and well aligned arm-like features. We analyzed the FCRAO $^{12}CO(J=\;1{\to}0)$ Outer Galaxy Survey data in this region to study the kinematical structure of this region, which resembles a big "scorpion". We found that there exist three different velocity components, about -54.5, -50.4, -48.8 km $s^{-1}$, depending on the position of the "scorpion". There also exist velocity gradients of 0.21 km $s^{-1}pc^{-1}$ and 0.16 km $s^{-1}pc^{-1}$ through the whole extent of the "scorpion". Interestingly, these two velocity gradients show an opposite direction with each other. It is likely that the velocity structure of this region may result from the mergence of different gas clouds, and the interaction with the SNR 109.1-1.0 occurred later, mostly at the region around the "head of the scorpion" only.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.07a
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• pp.152-152
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• 2004

• Proceedings of the Korean Nuclear Society Conference
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• 1998.10a
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• pp.152-152
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• 1998

• Nuclear Engineering and Technology
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• v.51 no.1
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• pp.228-237
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• 2019

The crack growth responses of as-received and as-welded Alloy 600/182 and Alloy 690/152 welds to constant loading were measured by a direct current potential drop method using compact tension specimens in primary water at $325^{\circ}C$ simulating the normal operating conditions of a nuclear power plant. The as-received Alloy 600 showed crack growth rates (CGRs) between $9.6{\times}10^{-9}mm/s$ and $3.8{\times}10^{-8}mm/s$, and the as-welded Alloy 182 had CGRs between $7.9{\times}10^{-8}mm/s$ and $7.5{\times}10^{-7}mm/s$ within the range of the applied loadings. These results indicate that Alloys 600 and 182 are susceptible to cracking. The average CGR of the as-welded Alloy 152 was found to be $2.8{\times}10^{-9}mm/s$. Therefore, Alloy 152 was proven to be highly resistant to cracking. The as-received Alloy 690 showed no crack growth even with an inhomogeneous banded microstructure. The cracking mode of Alloys 600 and 182 was an intergranular cracking; however, Alloy 152 was revealed to have a mixed (intergranular + transgranular) cracking mode. It appears that the Cr concentration and the microstructural features significantly affect the cracking resistance and the cracking behavior of Ni-base alloys in PWR primary water.

• The Bulletin of The Korean Astronomical Society
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• v.36 no.2
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• pp.152.2-152.2
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• 2011

M형 항성 주변의 외계행성 탐색 등을 위하여 근적외선 영역에서 정밀 신선속도 측정에 대한 관심이 근래 증가하고 있다. 이번 발표에서는 IGRINS를 이용하여 정밀 시선속도 측정을 하기 위한 방법과 이를 위한 필요한 일들을 소개하려 한다. 아울러 IGRINS로 정밀 시선속도를 측정하여 할 수 있는 연구 주제도 소개한다.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.152.1-152.1
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• 2005

• Proceedings of the Materials Research Society of Korea Conference
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• 1998.08a
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• pp.152.4-152
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• 1998

• Journal of Ocean Engineering and Technology
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• v.12 no.3 s.29
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• pp.42-48
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• 1998

구형 관입시험에 의한 얼음의 균열을 연구 하였다. $-10^{circ}C$에서 S2 기둥얼음의 시편(152mm X 152mm X 152mm)에 stainless 강으로 된 구(지름 25.4mm)로 하중을 가하였다. 구형indentor는 얼음 시편의 장축인 기둥방향에 수직으로 하중을 가하였으며 이때 변위율은 0.038mm/s로 하여 단조증가 하중 시험을 하였다. 하중을 가하기 시작하면 indentor 하부에서 crushing 이 발생하고, 하중이 증가함에 따라서 방사선 균열 또는 횡균열이 성장하여 splitting 또는 spallation이 발생하였다. 단조증가 하중 때와 동일한 indentor를 사용하여 하중 및 비하중율 0.5KN/s로 맥박하중을 가할 때 이들 방사선 균열 및 횡 균열이 발생 성장하였다. 첫 맥박 하중의 크기는 1KN으로 하고 그 뒤 계속 이어지는 시험은 맥박 하중의 크기를 증가시킨 뒤 행하였으며 균열 길이는 맥박과 맥박 사이에서 계측 하였다. 기타 취성고체에서 관찰 되었던 것과 같이 방사선 균열 및 측면균열의 길이는 impression 반지름과 하나의 지수법칙이 성립함을 보여주었다.

• Restorative Dentistry and Endodontics
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• v.42 no.2
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• pp.152-155
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• 2017

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.256-261
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• 2005

In the present experimental study, condensation heat transfer coefficients between R404A and R152a flow in a horizontal smooth tube were compared. The outer and inner diameters of the tube were 9.52 mm and 7.55 mm, respectively, and the heated length was 1045 mm. The mass flux ranged from 150 to 400 $kg/m^{2}s$ and the test section were uniformly heated from 8 to 12. $kW/m^2$. The quality range was from 0.2 to 0.8 at the saturation temperature from 27.3 to $34^{\circ}C$. Experimental condensation heat transfer coefficients increased as the quality and mass flux increased. Modified Dobson and Chato correlation reduced the mean deviation of 5.1% for R404A and 9.4% for R152a than the original correlation$^{(2)}$.