• Title/Summary/Keyword: Triple-A

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Development of Bi-directional Triple-eccentric Type Butterfly Valve (양방향 삼중편심 버터플라이 밸브 개발)

  • Kim, Soo-Young;Lee, Dong-Myung;Bae, Jung-Hoon;Shin, Sung-Chul;Sul, Chang-Ho
    • Journal of the Society of Naval Architects of Korea
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    • v.46 no.5
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    • pp.545-551
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    • 2009
  • In naval architecture and offshore engineering, the development and a broad use has been achieved in the field of flow control valves for pipe system. Butterfly valves are also widely used for flow control, but there are not many studies for triple-eccentric butterfly valves. Moreover, if the fluid of pipeline flows in the bi-direction then it makes more complicate to adapt triple-eccentric butterfly valves to flow control. In this study, we are trying to develop a bi-directional triple-eccentric butterfly valve through sealing mechanism and stem design study. Digital mockup using 3D CAD was constructed for shape interference check and structural analysis was conducted for structural safety. Also we performed leakage test to check out the durability of the bi-directional pressure for the developed valve.

A Study on the Flow Analysis of Triple Eccentric Butterfly Valve with Two-way Pressure (양방향 압력에 작동 가능한 3중 편심 버터플라이 밸브의 유동해석에 관한 연구)

  • RYU, M.R.;PARK, H.J.;KIM, J.H.;LEE, D.H.;LEE, S.B.
    • Journal of the Korean Society of Mechanical Technology
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    • v.13 no.1
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    • pp.81-88
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    • 2011
  • The triple eccentric butterfly valve has metal sheet and this study about butterfly valve ceiling is an innovative approach. But it is affected by the static pressure as well as cross-current. The damage at the valve on the pipe resulted from the reflux is due to valve leakage. This study is investigated on the triple eccentric disk and it is applied with angle and the static pressure in all cases to develop cross-current triple eccentric butterfly valves. The disc with the diameter of 300A is valve against flow velocity. The entrance pressure by flow characteristics is performed with numerical analysis. As the result, valve torque production is reduced more than the conventional triple eccentric valve and entrance pressure is decreased on the increase of valve open angle. And flow coefficient can be known to be increased.

A Study on the Flame Configuration and Flame Stability Mechanism with a Nozzle Diameter of Laminar Lifted Jet Flame (층류제트 화염의 노즐직경에 따른 안정화 메커니즘과 화염형상에 관한 연구)

  • Kim, Tae-Kwon;Kim, Kyung-Ho;Ha, Ji-Soo
    • Journal of Advanced Marine Engineering and Technology
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    • v.35 no.2
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    • pp.204-215
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    • 2011
  • Flame stability is the one of the main mechanism of laminar lifted flame and flame propagation velocity becomes a yardstick to measure the flame stability. Bilge has presented the flame propagation velocity of the triple flame and the flame stability mechanism related the flame configuration and mixture fraction. However, there was not able to observe all process of flame ignition and extinction for small nozzle diameter. In this paper, we have subdivided the flame configuration and stability mechanism and classified the flame behavior with a nozzle diameter. Also we have subdivided the 'triple flame propagation opened' and the 'triple flame propagation closed' from the triple flame propagation of triple flame criterion.

Triple Helix of University-Industry-Government Relations in Biotechnology Cluster: the Case of Singapore (바이오 클러스터에서의 트리플 힐릭스 관계 연구: 싱가포르 사례를 중심으로)

  • Nam, Jae-Geol
    • Journal of the Economic Geographical Society of Korea
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    • v.17 no.4
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    • pp.801-816
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    • 2014
  • This paper is a theoretically grounded empirical study aimed at shedding light on the Triple Helix of University-Industry-Government (U-I-G) relations in biotechnology cluster of Singapore. It questions the issue about the gap between theoretical consideration of the Triple Helix of U-I-G relations and the actual reality in biotechnology cluster, and the experience of Singapore was investigated. In terms of evolutionary perspective, biotechnology cluster in Singapore has gone through ongoing processes from a certain stage to other, and within the processes the Triple Helix nexus has been found. Analysis of the empirical study reveals significant findings: first, the government policies play a critical role in the operation of U-I-G relations rather than universities; second, therefore, the binding force of U-I-G relationships is based on the government policies being comprehensive including researchers immigration, student scholarship for local students, and tax and non-tax incentives for firms, rather than focusing on a targeted policy; third, the role of government starts from an initial stage, and it's role is ongoing processes by supporting infrastructure, human sources and continuous nourishment enabling the triple helix of U-I-G relations.

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AN EXTENSION OF THE TRIPLE HYPERGEOMETRIC SERIES BY EXTON

  • Lee, Seung-Woo;Kim, Yong-Sup
    • Honam Mathematical Journal
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    • v.32 no.1
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    • pp.61-71
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    • 2010
  • The aim of this paper is to extend a number of transformation formulas for the four $X_4$, $X_5$, $X_7$, and $X_8$ among twenty triple hypergeometric series $X_1$ to $X_{20}$ introduced earlier by Exton. The results are derived from the generalized Kummer's theorem and Dixon's theorem obtained earlier by Lavoie et al..

Triple Negative Breast Cancer

  • Cetin, Idil;Topcul, Mehmet
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2427-2431
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    • 2014
  • Triple-negative breast cancers (TNBC), characterized by absence of the estrogen receptor (ER) and progesterone receptor (PR) and lack of overexpression of human epidermal growth factor receptor 2 (HER2), have a poor prognosis. To overcome therapy limitations of TNBC, various new approaches are needed. This mini-review focuses on discovery of new targets and drugs which might offer new hope for TNBC patients.