• Journal of Astronomy and Space Sciences
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• 제21권1호
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• pp.11-28
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• 2004

고위도의 이온권 전기장이 열권 역학에 어떻게 영향을 주는지를 이해하기 위하여, 미 국립대기연구소(NCAR)의 열권-이온권 전기역학적 대순환 모델(TIEGCM)을 이용하여 고위도 하부 열권의 바람을 연구하였다. 1992-1993년 기간의 남반구 여름철 조건에 대해 모델을 가동하였으며, 행성간 자기장(IMF)에 좌우되는 이온권 대류가 바람에 미치는 영향을 살펴보기 위하여 IMF와 열권 바람과의 관련성을 또한 조사하였다. 비록 모델로부터 추정된 바람의 세기가 WINDII관측치에 비해 대체적으로 약하긴 하지만, 바람의 형태는 잘 일치하였다. 고위도 여름철 열권 바람에 대한 이온권 대류의 영향이 105km까지 나타나는 것으로 확인되었다. IMF$\neq$O와 IMF=0인 경우의 바람차이(difference wind)는 IMF$B_y$성분이 양과 음일 때 각각 시계방향과 반시계방향의 강한 소용돌이 형태를 보이며, 이 소용돌이 양상은 고도 105km까지 나타났다. IMF $B_z$가 양인 경우의 바람차이는 극관에 아주 국한되는 반면, IMF $B_z$가 음일 경우에는 아오로라(subauroral) 위도까지 확장되었다. IMF $B_z$에 좌우되는 일주풍(diurnal wind) 성분과 이온권 대류 성분 사이에는 뚜렷한 상관관개를 보이며, 그 관련성은 고도 108km까지 나타나고, 그때 일주풍은 강한 회 전성을 나타냈다 하부 열권의 여름철 동서성분바람의 자기지방시(MLT) 평균에 대한 IMF $B_y$ 영향은 고위도에서 상당히 크며, 최대 풍속은 지자기 위도 $77^{\circ}$부근의 고도 130km에서 약$60ms^-1$로 나타났다.

• Ocean and Polar Research
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• 제43권4호
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• pp.205-217
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• 2021

A shallow channel between Jeju and Udo Islands, which is located in the northeastern Jeju Island, is influenced by storm- or typhoon-induced currents and surface waves as well as strong tidal currents. This study examines the typhoon-induced current and wave patterns in the channel, using Acoustic Doppler Current Meter (ADCP) measurements and an ocean-wave coupled modeling experiment. Three typhoons were chosen - Chaba (2016), Soulik (2018), and Lingling (2019) - to investigate the responses of currents and waves in their pathways. During the pre-typhoon periods, dominant northward flow and wave propagation were observed in the channel due to the southeasterly winds before the three typhoons. After the passage of Chaba, which passed over the eastern side of Jeju Island, the northward flow and wave propagation were totally reversed to the opposite direction, which was attributed to the strong northerly winds on the left side of the typhoon. In contrast, in the cases of Soulik and Lingling, which passed over the western side of Jeju Island, strong southerly winds on the right side of the typhoons continuously intensified the northward current and wave propagation in the channel. The model-simulated current and wave fields reasonably coincided with observational data, showing southward/northward flow and wave propagation in response to the right/left side of the typhoon pathways. Typhoon-induced downwind flows, and surface waves could enhance up to 2m/s and 3m due to the strong winds that lasted for more than 12 hours. This suggests that the flow and wave patterns in the Udo channel are highly sensitive to the pathway of typhoons and accompanying winds; thus, this may be a crucial factor with regard to the movement of seabed sediments and subsequent coastal erosion.

• 천문학회보
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• 제21권
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• pp.8.1-8.1
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• 1996

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2004년도 학술대회지
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• pp.111-116
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• 2004

We surveyed the coastal structure damages due to the typhoon 'Mae-mi' which heavily struck Korean peninsula in September 12, 2003. The survey revealed the typhoon induced high tides and strong winds were the main causes especially in Busan areas. Though some experimental real time coastal monitoring stations captured the typhoon movements at the critical time, more systematic and complete systems should be implemented to save human lives and properties from huge typhoon disasters.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.331-332
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• 2008

Wind energy issued as most spotlight general energy by excellence of actuality as well as economical efficiency, solving environmental problem which caused by creating the energy and possibility of eternal production. Accordingly, government is at the stage of corresponding level by requesting development of new technology to the developed countries as a part of national key industries. The grievous situation from such a rapid movement is meteorological comprehension and assessment as well as the problem of estimation exactness about the wind. In this study, we use the regional meteorological station data, automatic weather station data and QuikSCAT SeaWinds data.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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• pp.656-656
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• 2002

It is studied on the relationship between the occurrence of red tide(Chlorophyll-a concentration by the in-situ and satellite data) and the meteorological factors (precipitation, air temperature, sunshine and winds) in the coastal areas in the South Sea of Korea. In summer and early-fall which frequently occurred the red tide, the precipitation above 213mm had directly influence on the occurrence of red tide because it carried the nutritive substance which originated from the land into the coastal areas. Then air temperature kept up generally high values as 23~26$^{\circ}C$, and sunshine with 187~198hours and wind velocity with 3.1~7.9m/s showed not directly the relationship on the occurrence of red tide.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 1999년도 Proceedings of International Symposium on Remote Sensing
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• pp.135-139
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• 1999

Wind velocity is one of the primary variables for describing atmospheric state from GMS-5. And its accurate depiction is essential for operational weather forecasting and for initialization of NWP(Numerical Weather Prediction) models. The aim of this research is to incorporate imagery from other available spectral channels and examine the error characteristics of winds derived from these images. Multi spectral imagery from GMS-5 was used for this purpose and applied to Korean region with together BoM(Bureau of Meteorology). The derivation of wind velocity estimates from low and high resolution visible, split window infrared, and water vapor images, resulted in improvements in the amount and quality of wind data available for forecasting.

• Wind and Structures
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• 제11권2호
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• pp.137-152
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• 2008

This paper discusses engineering aspects of the rear-flank downdraft that was recorded near Lubbock, Texas on 4 June 2002, and produced a gust wind speed nearly equal to the design value (50-year return period) for the region. The general characteristics of the storm, and the decomposition of the time histories into deterministic 'running mean' and random turbulence components are discussed. The fluctuating wind speeds generated by the event can be represented as a dominant low-frequency 'running mean' with superimposed random turbulence of higher frequencies. Spectral and correlation characteristics of the residual turbulence are found to be similar to those of high-frequency turbulence in boundary-layer winds. However, the low-frequency components in the running-mean wind speeds are spatially homogeneous, in contrast to the low-frequency turbulence found in synoptic boundary-layer winds. With respect to transmission line design, this results in significantly higher 'span reduction factors'.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 춘계학술발표회
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• pp.141-151
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• 2003

In this study the writer would like to study the art of navigation in the Era of Silla. For the purpose of this study, the writer studied ship's log book of Ennin's Diary, the ancient ship's structures of Korean, Chinese, Japanese, winds and ocean currents around Korean Peninsular which effect the navigation of sailing ship, and ancient reference books and materials. The result of this study. in the ship's structure in the Era of Silla. bottom structure is considered flat and V-Shaped type, and sailing ship had anchor, sail, considerable deckhouse, transverse bulkhead. And the ship's main materials of sailing ship was wood. partially used irons in the panting structures. In the art of navigation, navigators used winds, ocean current, anchor, sail, depth and color of sea water, lights, ballast. Especially navigators used astrologers and geomancers for astronomical observation, weather forecast, natural phenomena.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2006년도 추계학술발표회
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• pp.201-204
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• 2006

태풍의 경우, 주요 자연재해 중의 하나로 태풍의 상황을 정확하게 파악하는 것은 기상예측의 정도를 높이고, 재해를 방지하는데 중요한 역할을 할 수 있다. 일반적으로 태풍의 동향을 감시하는데 있어, MTSAT 등의 기상위성이 주로 활용되고 있다. 근년 인공위성의 원격탐사를 이용하여 광범위의 해양에 대한 해상풍과 파랑의 관측이 가능하게 되었다. 본 연구에서는, 2000년 QuickSCAT위성에 의한 해상풍의 월변동 특성을 조사하고, 7월에 한반도에 영향을 준 태풍 카이탁내의 해상풍을 검토하였다. 추가로 2005 년 8월 30일의 태풍 탈림에 대해서 ENVISAT ASAR Scan SAR에 의한 해상풍 추출을 시도하였다. QuickSCAT 에 의한 풍향을 이용한 방법과 SAR 자체의 패턴을 이용한 방법이 비교되었다.