• 제목/요약/키워드: Song type

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건설 예정인 댐에서 유역유출과 취수형태에 따른 탁수의 거동 예측 (Simulation of Turbid Water According to Watershed Runoff and Withdrawal Type in a Constructing Reservoir)

  • 박재충;최재훈;송영일;유경미;강보승;송상진
    • 환경영향평가
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    • 제19권3호
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    • pp.247-257
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    • 2010
  • Watershed runoff and turbid water dynamics were simulated in the Youngju Dam, being constructed. The runoff flow and suspended solids were simulated and then thermal stratification and turbid water current in the reservoir were predicted by HSPF and CE-QUAL-W2 model, respectively. Considering selective withdrawal, we hypothesized 3 withdrawal types from the dam, i.e. surface layer, middle layer and the lowest layer. The maximum concentration of SS was 400mg/L in reservoir and it was decreased by the withdrawal. The inflowed turbid water fell to 30 NTU after 12 days regardless of the withdrawal types, but the surface layer withdrawal was a better type at turbid water discharge than the others. In current environmental impact assessment(EIA), we concluded that runoff and reservoir water quality predicted by HSPF and CE-QUAL-W2 was desirable, and appropriate parameters were selected by continous monitoring after EIA.

V-gutter형 보염기를 장착한 모델 연소기 내의 연소 주파수 발생 메커니즘 연구 (An Experimental Study on Mechanism of Combustion Frequencies in Model Combustor with V-gutter type Flameholder)

  • 송진관;황정재;송재천;윤영빈;이종근
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2009년도 춘계학술대회 논문집
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    • pp.277-280
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    • 2009
  • 본 연구는 v-gutter형 보염기를 장착한 연소기 내에 발생한 연소 주파수의 발생 메커니즘에 대해 규명 하는 것이다. 연소기는 $40{\times}40\;mm$의 단면적을 가진 긴 덕트 형상을 가지고 있으며, 14mm의 폭을 가진 v-gutter 형의 보염기를 장착하였다. 연료로 등유와 메탄를 수직 분무하여 실험을 수행하였다. 연소 시 발생하는 주파수는 연소기의 형상에 기인한 1L 종방향 모드와 보염기에서 발생하는 와류 주파수가 주로 발생함을 확인하였다. 또한 연료의 특성에 기인한 주파수와 노즐의 영향에 대한 주파수가 저주파 영역에서 발생함을 확인하였다.

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PHRAGMEN-LINDELOF AND CONTINUOUS DEPENDENCE TYPE RESULTS IN GENERALIZED DISSIPATIVE HEAT CONDUCTION

  • Song, Jong-Chul;Yoon, Dall-Sun
    • 대한수학회지
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    • 제35권4호
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    • pp.945-960
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    • 1998
  • This paper is concerned with investigating the asymptotic behavior of end effects for a generalized heat conduction problem with an added dissipation term defined on a three-dimensional semi-infinite cylinder. With homogeneous Dirichlet conditions on the lateral surface of the cylinder it is shown that solutions either grow exponentially or decay exponentially in the distance from the finite end of the cylinder. In particular, to render decay estimate explicit, we pattern after the analysis of Payne and Song [13, 15]. The continuous dependence effect of perturbing the equations parameters is also investigated.

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