• Title/Summary/Keyword: 延安

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Fish Fauna in Coastal Waters of Ulleungdo, Korea by SCUBA Investigation in Summer (다이빙 조사에 의한 여름철 울릉도 연안의 어류상)

  • Myoung, Jung-Goo;Park, Jeong-Ho;Cho, Sun-Hyung;Kim, Jong-Man
    • Korean Journal of Ichthyology
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    • v.17 no.1
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    • pp.84-87
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    • 2005
  • The fish fauna was investigated in the coastal waters of Ulleungdo by SCUBA diving from 27 to 28 July 2004. We observed a total of 45 species from 22 families, including 6 species in Scorpaenidae and 5 species in Labridae. A total of 33 species were recorded at Station 1, and 15 species were recorded at Station 3. As a result of this study, we newly added 23 species to fish list in the coastal waters of Ulleungdo.

Numerical Simulation on Longshore Current Produced by Random Sea Waves (불규칙파에 의한 연안류의 수치계산)

  • 권정곤
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.3 no.1
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    • pp.54-64
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    • 1991
  • To accurately estimate the rate of sediment transport in shallow water bodies, it is necessary to investigate the irregular waves transformation characteristics and nearshore currents produced by random sea waves. Most of studies on numerical models for nearshore currents are based on the theory of monocromatic waves and thus, very few nearshore models take into account the effect of irregularities in the hight, period and directional spreading of incident waves. The numerical simulation model for nearshore currents used in this paper considers the effect of irregularities of incident waves, based on Individual Wave Analysis. The computational results are compared and shown in a reasionable agreement with the experimental data.

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First Record of the Gobiid fish, Clariger chionomaculatus (Perciformes: Gobiidae) from off Geojedo Island, Korea (우리나라 거제도 연안에서 채집된 망둑어과 첫기록종, Clariger chionomaculatus)

  • Cho, Hyun-Geun;Kim, Byung-Jik
    • Korean Journal of Ichthyology
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    • v.32 no.2
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    • pp.110-114
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    • 2020
  • A single specimen (40.5 mm in SL) of Clariger chionomaculatus was collected at 4 m depth on mud bottom from off Geojedo Island, Korea. This species is characterized by having an elongated body without scales, several barbels below eyes, I, 12~15 second dorsal fin rays, I, 12~14 anal fin rays; 19~20 pectoral fin rays with one free soft ray on upper part, and a unique color pattern with numerous white blotches on dorsal part of body. Because it has been known from Japan only to date, we describe in detail C. chionomaculatus as the first record from Korea. A new Korean name, "Huin-jeom-wae-mang-dug", is proposed for the species.

Comparative Evaluation of Three-dimensional Turbulence Models in Coastal Region (연안 해수유동에 관한 3차원 난류모형의 비교평가)

  • 정태성
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.8 no.3
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    • pp.256-267
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    • 1996
  • In estuarine 3-dimensional numerical modeling. it is very important to calculate vertical eddy viscosity accurately. Various turbulence models employing eddy viscosity concept were applied to the steady flow in an open-channel and the tidal flow in long tidal channel and compared. The evaluations include the verification tests against experimental data sets for steady and tidal flows. The simulation results have shown that the compared models are in good agreements with experimental data of steady flow while only $textsc{k}$-$\varepsilon$ model, $textsc{k}$-ι model, and 1-equation model with well-defined mixing length profile give good agreements with experimental data of tidal flow.

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A Study on the Heat Budget in the South Eastern Area of the Yellow Sea (황해 남동해역에서의 열수지에 관한 연구)

  • 이현철;안희수
    • 한국해양학회지
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    • v.22 no.4
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    • pp.217-227
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    • 1987
  • The heat budget of the south eastern region (33$^{\circ}$N-36$^{\circ}$N, 120$^{\circ}$E-125$^{\circ}$E) of the Yellow Sea was calculated by using the meteorological and oceanographical data. The sensibly heat, the evaporation heat and the long wave back radiation have annual variation and increases toward south with strong gradient along the Cheju channel in winter, but they all show tendency to decrease toward eastern coastal area in summer. The area is roughly divided into three parts, the central part, the coastal part and the southern part, according to the characteristics ovariation and distribution patterns of the exchanged heats. The amplitude of the annual variation of total heat exchange in the southern part is very large compare to those of the central and coastal part. The studied area is appeared to be heated mainly by the evaporation heat and the sensoble heat, based on the results of this study.

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A Systematic Study on the Asteroidea in the East Sea, Korea (한국 동해산 해성류의 계통분류학적 연구)

  • Sook Shin
    • Animal Systematics, Evolution and Diversity
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    • v.11 no.2
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    • pp.243-263
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    • 1995
  • Twenty-nine species of asteroids are reported to be distributed in the East Sea of Korea. Five species are reported to be distributed in the East Sea of Korea. Five speices are reported for the first time in Korea ; Solaster endeca (Linn, 1771), Lethasterias fusca D'yakonov, 1931, Lethasterias nanimensis chelifera (verrill, 1914), Lysastrosoma anthostictha Fisher, 1992 and Evasterias troscheli alveolata Verrill, 1914. The faunal composition and distribution of the asteroids in the East Sea of Korea are discussed.

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Optimal Design of Storm Sewer by Computations of Feasible Hydraulic Gradient Line (합리적 동수위 계산을 통한 최적 배수관로 설계)

  • Yoo, Hee-Sang;Kim, Mun-Mo;Ahn, Won-Sik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1585-1589
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    • 2009
  • 최근 빈발하는 국지성 호우나 태풍에 의한 집중호우로 도시지역의 내배수불량으로 인하여 저지대 및 지하공간의 침수현상이 빈번히 야기하고 있는 실정이다. 특히 연안이나 외수위의 영향으로 강제배수가 요구되는 지역인 경우에는 개발에 앞서 선결해야할 중요한 재해저감대책 중의 하나이다. 이에 본 연구에서는 연안의 해수면 및 하천 홍수위로 인한 계획단지 내 배수관로의 동수위 산정을 위한 유출모의를 수행하였다. 연안저지대의 순성토 지역인 경우 동수위 계산에 따른 성토량에 의한 비용이 전체 공사비 결정 요인의 가장 큰 부분을 차지하고 있으므로 이에 따른 경제적이면서 치수안전도를 증가시킬 수 있는 계산 방법을 정립하는 것은 선결되어야 할 문제이다. 이를 위해 도시유역에 범용적으로 사용되고 있는 SWMM 모형을 활용하였다. SWMM 모형 중에서 EXTRAN 블록을 통한 유출모의는 관거내 동수경사를 계산하여 배수, 역류, 압력류, 월류까지도 모의할 수 있다. 다양한 조건으로 배수관로의 설계를 통한 동수위와 성토고를 분석하여 조건별 경제성과 치수안전도를 검토할 수 있으나 관로 크기, 경사, 방향 등을 우선하여 변경해가면서 최적안을 확인하였다. 검토된 계산 절차에 따라서 향후 지형적으로 유사한 지역에서의 배수시스템 설계에 적용 및 기존 배수관망 재설계 및 확장 등의 검토에 효과적으로 적용할 수 있을 것이다.

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Numerical Optimization of Foundation place for Domestic Offshore Wind Turbine by using Statistical Models for Wind Data Analysis (기상풍황자료 통계적 분석을 통한 한국형 해상풍력터빈 설치지점 선정 최적화 연구)

  • Lee, Ki-Hak;Jun, Sang-Ook;Ku, Yo-Cheon;Pak, Kyung-Hyun;Lee, Dong-Ho
    • 한국신재생에너지학회:학술대회논문집
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    • 2007.06a
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    • pp.404-408
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    • 2007
  • 현재 국내에서 운용중인 풍력발전시스템은 국내 풍력자원에 대한 정확한 정보의 부재와 국내 풍황에 맞지 않는 국외 모델을 그대로 운용하는 등의 몇 가지 문제를 드러내었다. 본 연구의 목적은 국내 연안의 해상에서 한국형 해상풍력터빈을 설치하기 위한 잠재적 최적위치와 풍황자료 산출 최적화 알고리즘을 구현하는 것이다. 최적화 알고리즘은 얕은 수심 분포와 연안에서의 거리를 제약조건으로 하고 최대 에너지밀도를 가진 지점을 구하는 것으로 정식화하였다. 풍황자료 산출을 위해서 국내 연안의 해상 풍황자료를 포함하는 기상풍황자료를 통계적 모델로 분석하여 바람지도를 작성하였다. 이 바람지도를 이용하여 지질 통계학 분야의 관측기법인 크리깅 모델을 구성하고, 전역최적화기법인 유전자알고리즘을 이용하여 제약조건을 만족하는 최대에너지밀도값과 그 위치를 도출하였다. 수치최적화 결과 우리나라 풍력 자원의 대략적인 잠재량과 현황파악이 가능하였고, 해상풍력발전단지가 조성 가능한 개략적인 위치를 예측할 수 있었다.

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On the Annual Variation of Mean Sea Level along the Coast of Korea (한국연안 평균 해면의 연변화)

  • 강용균;이병돈
    • 한국해양학회지
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    • v.20 no.1
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    • pp.22-30
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    • 1985
  • The mean sea level(MSL) along the coast of Korea is high in summer and low in winter, mainly due to the inverse barometric effect and the steric departure. The MSL associated with the inverse barometric effect is spatially uniform and has an amplitude of 8.5$\pm$0.8cm. The thermal departure, with amplitude of 4~8cm, is most dominant in the Yellow Sea. The MSL in the South Sea of Korea is strongly affected by the haline departure, which has an amplitude up to 5cm. The annual range of MSL along the western and eastern coasts of Korea are about 40 and 20cm, respectively. The spatial inhomogeneity of the annual range of MSL arises mainly due to the influence of the Asian monsoon, which amplifies (weakens) the annual MSL along the western (eastern) coast of Korea.

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Nonlinear Dispersion Model of Sea Waves in the Coastal Zone (연안역에서의 비선형 파낭 분산모형)

  • Pelinovsky, Efim N.;Stepanyants, Yu.;Talipova, Tatiana
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.5 no.4
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    • pp.307-317
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    • 1993
  • The problem of sea wave transformation in the coastal zone taking into account effects of nonlinearity and disperison has been studied. Mathematical model for description of regular wave transformation is based on the method of nonlinear ray theory. The equations for rays and wave field have been produced. Nonlinear wave field is described by the modified Korteweg-de Vries equation. Some analytical solutions of this equation are obtained. Caustic transformation and dissipation effects are included in the mathematical model. Numerical algorithm of solution of the Korteweg-de Vries equation and its stability criterion are described. Results of nonlinear transformation of sea waves in the coastal zone are demonstrated.

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