• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.1
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• pp.1-7
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• 2013

An aerodynamic rig test of a radial turbine for an auxiliary power unit (APU) was performed at a high-temperature turbine test facility at the Korea Aerospace Research Institute. The pressure ratio, Mach number, and flow coefficient in the rig test are the same as those under normal engine operation conditions. The design pressure ratio is 3.096, design test speed is 34909 rpm, and turbine inlet temperature is $160^{\circ}C$. The turbine has airfoil-type nozzles, and the diameter of the turbine wheel is 175.74 mm. The turbine map is experimentally measured, and the detailed flow at the turbine inlet is measured. The pressure distribution in the nozzle at both the hub and the shroud sides and the pressure distribution along the shroud casing of the turbine wheel were measured, and this confirmed that the expansion process in the turbine wheel is acceptable.

• The Journal of the Acoustical Society of Korea
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• v.37 no.2
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• pp.83-91
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• 2018

The noise sources of a tip-jet driven rotor can be separated by rotor blade noise and jet noise. The rotor blade noise consists of thickness noise, loading noise, nonlinear quadrupole noise, and jet noise is divided into nozzle momentum noise and jet radiation noise. The flow analysis for the prediction of rotor blade noise is performed by CFD (Computational Fluid Dynamics) analysis, and the noise source of the rotor blade noise is identified by simultaneously applying the permeable and impermeable surface based FW-H (Ffowcs Williams-Hawkings) acoustic analogy. The nozzle momentum noise is obtained by permeable surface FW-H, and jet radiation noise is predicted by using empirical method for the fixed-wing jet. Both of jet noises use nozzle exit condition for noise analysis. The accuracy of the technique is verified based on the noise measurements of the tip-jet driven rotor, and the unique noise characteristics of the tip-jet driven rotor is confirmed by spectrum analysis.

• Korean Journal of Plant Resources
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• v.18 no.3
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• pp.490-496
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• 2005

This study was conducted to clarify the effects of chemicals and physical treatment on the split of flower stalk and the vase life of Lycoris squamigera and Lycoris radiata. There was no split of flower stalk for the Lycoris squamigera and the Lycoris radiata after the harvest of flowers and the immersion in 4 mM STA solution for 30 minutes. It was effective for the vase life of Lycoris squamigera that cut flower was pre-treated in 4 mM STS solution for 30 minutes and immersed in $5\~10\%$ sucrose + 150 ppm 8-HQS +4 ppm Rox preservative solution. The optimum periods of hot water treatments for the prevention of flower stalk split and the elongation of vase life for the cut flowers were 15 to 25 seconds for the Lycoris squamigera and 5 to 10 seconds for Lycoris radiata. Burning the cut parts of flower stalk for 10 to 30 seconds was effective for the prevention of flower stalk split and the elongation of vase life for the Lycoris squamigera, and 10 to 15 seconds for the Lycoris radiata. The vase lifes of Lycoris squamigera and Lycoris radiata were elongated when flower stalk was cut by an incline of 45 degrees compared with the horizontal cut. And Banding the flower stalks of cut flowers was effective for the prevention of flower stalk split and the elongation of vase life for the Lycoris squamigera and the Lycoris radiata.

• The Korean Journal of Coaching Psychology
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• v.7 no.1
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• pp.1-31
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• 2023

The purpose of this study is to verify the mediating effect of adaptive cognitive emotion regulation and the moderating effect of supervisor's emotional regulation in the relationship between the emotion recognition and negative feedback acceptance of employees. The data was collected from 273 non-managerial workers in various domestic companies. Confirmatory factor analysis was conducted with AMOS 22 to verify the reliability and validity of the measurement tool, and the mediating and moderating effects were examined using SPSS Process Macro to verify the hypothesis. The results of this study are summarized as follows. First, emotion recognition of employees indirectly affects the acceptance of negative feedback through adaptive cognitive emotional regulation. Second, the effect of emotion recognition on negative feedback acceptance is moderated by supervisor's emotion regulation. Specifically, it was confirmed that when the supervisor's emotional control is low, the relationship between emotional recognition and negative feedback acceptance becomes stronger. Based on the results of the study, it was confirmed that the level of awareness of oneself and others' emotions was psychological process of accepting performance-related feedback, and the importance of supervisor's emotional regulation in positively accepting negative feedback. Finally, based on the research results, the academic significance of this study, implications in coaching practice, limitations, and future research were discussed.

• The Optical Journal
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• v.12 no.2 s.66
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• pp.12-14
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• 2000

올 해 35mm 카메라 시장 규모는 전년에 비해서 소폭 성장할 것으로 전망되나, 일본업체들의 본격적인 마케팅과, 삼성카메라의 적극적인 수성 지키기, LG상사의 의욕적인 카메라 사업 참여 등으로 업체별 경쟁은 더욱 치열할 것으로 예상된다. 디지털카메라 시장은 130만$\~$200만 이상의 고화소 제품을 중심으로 시장이 형성되고, 시장규모도 급속한 성장을 거듭하면서 200억 이상이 될 것으로 예상된다.

• Transactions of Materials Processing
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• v.1 no.2
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• pp.52-62
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• 1992

본 연구에서는 모델재료를 이용한 모사실험을 통하여 고온의 강을 단조하였을 때의 유동과 변형 그리고 하중을 검토하고, 이어 성형에 관한 연구를 하였다. 모델재료인 플라스티신은 고용의 강을 모사하는데 많이 쓰이는데, 실험을 통하여 플라스티신과 강과의 변형저항식을 비교 검토하였다. 이 실험결과 상사성이 어느정도 일치함을 알았고, 이 상사성 결과를 이용하여 실제와 모델사이의 하중과 응력비를 검출하였다. 이로써 플라스티신을 이용한 단조 압축 실험을 통하여 실제의 하중을 예측하였다. 또한 예비 성형체를 설계하기 위하여 앞서 실험한 결과들을 이용하여 초기의 실린더의 체적과 치수를 결정하고 이에 단계에 따른 성형과정을 통하여 예비 성형체를 만들었는데, 이는 제한된 용량으로 성형하여야 하는 문제를 해결하기 위함이었다. 실험 결과 8단계에 따른 성형과정에 의해 우리가 원하는 대형 단조품을 성형할 수 있음을 알았다.

• Korean Journal of Heritage: History & Science
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• v.20
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• pp.239-278
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• 1987

보성군에서 수집한 민요들의 의식·노동·유희요(謠) 별(別)로 정리하였다. 의식요(儀式謠)로는 걸메당·상여·독경(讀經)소리가 실렸다. 전래(傳來) 혼인식(式)에 있어서의 가마소리인 걸메당소리는 전국의 몇 곳에서만이 가창자가 남아 있는 희요(稀謠)이다. 상여소리(처음에 운구 들어 울릴때의 긴소리, 길 갈 때의 가난보살과 어가리넘자, 비탈길 오를 때의 나무아미타불, 달구소리)는 전남지방에 널리 전파되어 있는 것과 동계(同系)이다. 노동요(謠)는 주로 농요(農謠)<광의(廣義)>가 수집되었다. 소동패전갈을 수록하였다. 모심기곡(曲)은 공(共)히 일반 농부가 쪼임에 비하여 모찌기와 논매기곡(曲)(<표2>참조)은 다양성을 띄웠다. 산아지로고나곡(曲)은 전(全) 면(面)에 두루 퍼져 있으며 논맬 때, 장원질소리, 소동패노래에도 쓰인다. 산떨이(올라간다)는 고흥군의 것과 같다. 터 다지는 노래로는 얼럴럴 상사도야를, 상량노래로는 어유아 상량이야를 부른다. 줄메고 나가는 노래의 받음구는 위야허허 또는 상사뒤여뒤여(회촌면)이다. 유희요(謠)는 남사당의 덜미 (꼭두각시극)노래인 떼루와 제나난실을 싣고 그 위에 치마·줌치·사위·강도령·이노래 등을 실었다.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.33 no.2
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• pp.39-45
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• 2005

The aim of this research is to predict the thickness and loading noise of the round-tip shaped Hartzell propeller currently used in the general aviation aircraft. Before implementing the noise analysis, the pressure distribution on the propeller was obtained by using the free wake panel method and unsteady Bernoulli's equation. The noise signal at observer position can be obtained by using the FW-H equation. The noise prediction results for the propeller indicates that the thickness noise has s symmetric directivity pattern with respect to the tip path plane, while the noise due to loading shows higher noise directivity toward downstream than the upstream direction from the rotor plane. The loading noise is dominant rather than the thickness noise in normal operating condition.

• Proceedings of the Korea Water Resources Association Conference
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• 1987.07a
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• pp.89-97
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• 1987

가로흐름에 방류되는 연직평면부력젤의 젤중심선경로와 온도분포를 실험자료와 기본방정식으로부터 유도된 적분식에 의하여 해석한다. 기본방정식으로부터 적분식의 유도는 상사법칙과 특성길이를 도입하여 연직상향 및 수평방향흐름영역에 대한 차원해석을 하였고, 실험은 속도비(R=Wo/Ua)와 방류밀도Froude수를 변화시키면서 각각에 따른 젤중심선경로와 온도분포를 획득하였다. 속도비 R과 방류밀도Froude수 Fo에 따라 부력젤의 흐름특성은 달라지게 되며, 초기조건(운동량및 부력)에관계없이 부력젤은 항상 운동량지배영역이 존재함을 알 수 있었고 적분식에 의한 역법칙(power law)과 실험 자료는 대체로 일치된결과를 나타내었다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.3
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• pp.485-496
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• 1992

본 연구에서는 제철, 제강공정에서 많이 사용하고 있는 C22FR1.4형의 주형을 상사적으로 축소시킨 주철제(GC25) 주형에 순알루미늄(순도99%)의 주물을 용입하여 응고 및 냉각 과정의 주물 및 주철제 주형에 미치는 열의 영향에 관하여 2차원 비정상 열전도 문제를 경계요소법으로 해석하고 실험을 통하여 검증하였다.