• Title/Summary/Keyword: semi-water jet

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A Numerical Analysis of Buyoyant Surface Jet with Turbulence Models (난류모형을 이용한 表層密度噴流의 수치해석)

  • 최한기;중십계
    • Water for future
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    • v.29 no.2
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    • pp.221-233
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    • 1996
  • To investigate the hydrodynamic characteristics of a two-dimensional buoyant surface jet, the most important factors of the numerical analysis are the evaluation of the free surface and the turbulence transportation under the stratification. In present study, a numeriacal simulation model used with the semi-implicit method for pressure-linked equations (SIMPLE), the non-hydrostatic approximation and the algebraic stress model (ASM) is applied to investigate the vertical structure of internal flow hydrodynamically. The ASM enables to take account of anisotropy of turbulence, the damping effects of the density interface, and the free surface on the turbulence structure accurately. The ASM tested produces better agreement than the $\kappa-\varepsilon$ model with measurements by Nakatsuji (1984) on the flow development and turbulence structure. Applicability of the ASM to a two-dimensional buoyant surface jet is examined through comparison with experimental data.

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A Study on the Development for the Coastal Fishing Boat attached Protected-Tunnel for Propeller (세미워터제트형 연안어선 개발에 관한 연구)

  • 고재용;심상목;박충환;서성부;배동균
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2003.05a
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    • pp.16-20
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    • 2003
  • Recently, The fast change of fishing boat fishery surrounding environment is connected by request of fan shape development that meet in restructuring of existing fishing boat fishery and new community, economical surrounding. In southern sea district along the coast work and district along the coast fishing bats that sail to exposed propeller fishing net, rope etc.. cold real condition that accident is increasing every year. This study is thing which analyze main performance of minuteness water jet type district along the coast fishing boat through model examination to propeller protection tunnel sticking district along the coast fishing boat that correct existing stem shape for marine accident prevention of district along the coast fishing boat in viewpoint such as ideal and examines.

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Patterns of Aquaporin 7 Expression in Normal Follicles and Follicular Cyst Follicles of Hanwoo (한우의 정상 난포와 난포낭종 난포에서 Aquaporin7 발현 양상)

  • Kim, Chang-Woon;Han, Sunkyu;Choe, Changyong
    • Journal of Embryo Transfer
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    • v.30 no.1
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    • pp.17-21
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    • 2015
  • Alteration in ion channel or transporter expression levels affects cell volume which is produced by movement of water and ion across the plasma membrane. In particular, aquaporin (AQP) channels among ion channels play a crucial role in movement of water across the cell membrane. This study was performed to identify whether AQP expression is changed in bovine follicular cystic follicles using microarray, RT-PCR and Western blotting analyses. In microarray data, AQP4 expression was decreased, whereas AQP7 was increased in cystic follicles. Additional experiments were focused on the AQP7 expression increased in cystic follicles. The microarray data was confirmed by semi-quantitative polymerase chain reaction (PCR) and Western blot analysis. AQP7 mRNA and protein expressions were significantly increased in the cystic follicles (p<0.05). Application of estrogen ($10{\mu}g/ml$) to bovine ovarian cells showed a trend of increase in AQP7 expression. From these results, we suggest that the increase in AQP7 expression in cystic follicles may play an important role in movement of water in bovine ovary. In addition, AQP7, a aquaglyceroporin permeating water and glycerol, could be a good target in development of methods for the cryopreservation of bovine ovary.

Effects of Heat Temperature in Sizing and Pretreatment Processes on the Appearance Colour of the Polyester Fabrics (사이징 및 전처리 공정에서의 열처리 온도 변화에 따른 폴리에스테르 직물의 염색성 변화)

  • Cho, D.H.;Kim, S.J.;Chang, D.H.
    • Textile Coloration and Finishing
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    • v.11 no.2
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    • pp.1-8
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    • 1999
  • 이 연구에서는 사이징 공정을 포함해서 수세, 전처리 그리고 최종 열처리 둥의 염색.가공 공정에서의 습열 및 건열 처리 온도가 폴리에스테르 직물의 열응력과 염색성에 미치는 영향을 조사하였다. 사용된 폴리에스테르 필라멘트사는 경사가 50d/24f 스파크사이며 위사는 75d/72f semi-dull사이다. 평직물은 션틀직기, 주자직물은 water jet 직기로 제직하였으며, sizing dryer 온도는 $90^\circ{C}$, $125^\circ{C}$, $150^\circ{C}$, 수세공정의 습열처리 온도는 $90^\circ{C}$, $110^\circ{C}$, $120^\circ{C}$, 전처리 공정의 건열처리 온도는 $180^\circ{C}$, $200^\circ{C}$, $220^\circ{C}$, 마지막 세팅 공정의 건열처리 온도는 $170^\circ{C}$, $180^\circ{C}$, $200^\circ{C}$로 변화시켰다. 이들 습열과 건열처리 온도 변화에 따른 직물내의 필라멘트사의 열 수축률과 직물의 겉보기 염색성의 변화를 조사 분석하였다.

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