• Title/Summary/Keyword: $K_s$

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Flow Resistance and Modeling Rule of Fishing Nets -2. Flow Resistance of Bag Nets- (그물어구의 유수저항과 모형수칙 -2. 자루형 그물의 유수저항-)

  • KIM Dae-An
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.28 no.2
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    • pp.194-201
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    • 1995
  • In order to make clear the resistance of bag nets, the resistance R of bag nets with wall area S designed in pyramid shape was measured in a circulating water tank with control of flow velocity v and the coefficient k in $R=kSv^2$ was investigated. The coefficient k showed no change In the nets designed in regular pyramid shape when their mouths were attached alternately to the circular and square frames, because their shape in water became a circular cone in the circular frame and equal to the cone with the exception of the vicinity of frame in the square one. On the other hand, a net designed in right pyramid shape and then attached to a rectangular frame showed an elliptic cone with the exception of the vicinity of frame in water, but produced no significant difference in value of k in comparison with that making a circular cone in water. In the nets making a circular cone in water, k was higher in nets with larger d/l, ratio of diameter d to length I of bars, and decreased as the ratio S/S_m$ of S to the area $S_m$ of net mouth was increased or as the attack angle 9 of net to the water flow was decreased. But the value of ks15m was almost constant in the region of S/S_m=1-4$ or $\theta=15-90^{\circ}$ and in creased linearly in S/S_m>4 or in $\theta<15^{\circ}$ However, these variation of k could be summarized by the equation obtained in the previous paper. That is, the coefficient $k(kg\;\cdot\;sec^2/m^4)$ of bag nets was expressed as $$k=160R_e\;^{-01}(\frac{S_n}{S_m})^{1.2}\;(\frac{S_m}{S})^{1.6}$$ for the condition of $R_e<100$ and $$k=100(\frac{S_n}{S_m})^{1.2}\;(\frac{S_m}{S})^{1.6}$$ for $R_e\geq100$, where $S_n$ is their total area projected to the plane perpendicular to the water flow and $R_e$ the Reynolds' number on which the representative size was taken by the value of $\lambda$ defined as $$\lambda={\frac{\pi d^2}{21\;sin\;2\varphi}$$ where If is the angle between two adjacent bars, d the diameter of bars, and 21 the mesh size. Conclusively, it is clarified that the coefficient k obtained in the previous paper agrees with the experimental results for bag nets.

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Object-Oriented Dynamic Programming: An Application to Unit Commitment (객체 지향형 동적 계획법을 이용한 화력 발전기의 기동정지계획)

  • Choi, S.Y.;Kim, H.J.;Jung, H.S.;Shin, M.C.;Suh, H.S.;Park, J.S.;Kwon, M.H.
    • Proceedings of the KIEE Conference
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    • 1998.07c
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    • pp.1140-1142
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    • 1998
  • This paper presents object-oriented dynamic programing formulation of the unit commitment problem. This approach features the classification of generating units into related groups so called class. All object which share the same set of attributes and methods are grouped together in classes and designed inheritance hierarchy to minimize the number of unit combination which must be tested without precluding the optimal path. So this programming techniques will maximize the efficiency of unit commitment.

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Growth of Thin Film using Chemical Bath Deposition Method and Their Photoconductive Characterics ($Cd_{1-x}Zn_{x}S$ 박막의 성장과 광전도 특성)

  • Lee, S.Y.;Hong, K.J.;You, S.H.;Shin, Y.J.;Lee, K.K.;Suh, S.S.;Kim, H.S.;Yun, E.H.;Kim, S.U.;Park, H.S.;Shin, Y.J.;Jeong, T.S.;Shin, H.K.;Kim, T.S.;Moon, J.D.;Lee, C.I.;Jeon, S.L.
    • Journal of Sensor Science and Technology
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    • v.4 no.3
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    • pp.60-70
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    • 1995
  • Polycrystalline $Cd_{1-x}Zn_{x}S$ thin film were grown on slide glass(corning-2948) substrate using a chemical bath deposition (C.B.D) method. They were annealed at various temperature and X -ray diffraction patterns were measured by X-ray diffractometor in order to study $Cd_{1-x}Zn_{x}S$ polycrystal structure using extrapolation method of X-ray diffraction patterns for the CdS, ZnS sample annealed in $N_{2}$ gas at $550^{\circ}C$. It was found hexagonal structure which had the lattice constant $a_{0}\;=\;4.1364{\AA}$, $c_{0}\;=\;6.7129{\AA}$ in CdS and $a_{0}\;=\;3.8062{\AA}$, $c_{0}\;=\;6.2681{\AA}$ in ZnS, respectively. Hall effect on these sample was measured by Van der Pauw method and then studied on carrier density and mobility depending on temperature. We measured also spectral response, sensitivity maximum allowable power dissipation and response time on these sample.

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Responsivity of IRTS/FILM in Orbit

  • Oh S.H.;Nakagawa T.;Kwon S.M.;Pak S.;Lee H.M.;Jeong W.S.;Makiuti S.;Pearson C.
    • The Bulletin of The Korean Astronomical Society
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    • v.28 no.2
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    • pp.28-28
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    • 2003
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Molecular Characterization and Expression Analysis of Ribosomal Protein S6 Gene in the Cashmere Goat (Capra hircus)

  • Bao, Wenlei;Hao, Xiyan;Zheng, Xu;Liang, Yan;Chen, Yuhao;Wang, Yanfeng;Wang, Zhigang
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.11
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    • pp.1644-1650
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    • 2013
  • Ribosomal protein (rp) S6 is the substrate of ribosomal protein S6K (S6 kinase) and is involved in protein synthesis by mTOR/S6K/S6 signaling pathway. Some S6 cDNA have been cloned in mammals in recent years but has not been identified in the goat. To facilitate such studies, we cloned the cDNA encoding Cashmere goat (Capra hircus) S6 (GenBank accession GU131122) and then detected mRNA expression in seven tissues by real time PCR and protein expression in testis tissue by immunohistochemisty. Sequence analysis indicated that the obtained goat S6 was a 808 bp product, including a 3' untranslated region of 58 bp and an open reading frame of 750 bp which predicted a protein of 249 amino acids. The predicted amino acid sequence was highly homologous to cattle, human, mouse and rat S6. Expression analysis indicated S6 mRNA was expressed extensively in detected tissues and S6 protein was expressed in testis tissue.