• 천문학논총
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• 제25권1호
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• pp.15-21
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• 2010

We report results of image simulations of the KVN and VLBI experiments of the KVN with several other East Asia VLBI facilities. To investigate their imaging capability a model-generated image of 7 mm SiO maser emission in Mira variables is used. The resulting simulations show that the joint VLBI experiments of the KVN with East Asia VLBI facilities can produce reasonably good images at 7 mm spectral line experiments. However, there are no apparent differences in peak flux densities and images themselves in the simulations among different combinations of these facilities. In addition, the simulated images of observations which include bigger antennas do not show any expected improvement to the image sensitivity. The small variations in the peak flux density and similar image sensitivity, irrespective of different antenna sizes or numbers of baselines used in the simulations, turn out due to a specific characteristic of the adopted model image. Test simulations using another SiO maser image from R Cas observations prove that the participation of bigger antennas in the VLBI experiments does improve image sensitivity. We confirm the need of additional longer baselines in the experiments of the East Asia VLBI facilities to study very compact maser clumps on sub-milliarcsecond scales.

• 아태비즈니스연구
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• 제2권1호
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• pp.49-73
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• 2011

With the market evaluation of economic globalization exchanges between different cultures, cultural trade has been developing at an accelerated speed, and also playing an important role in East Asian intra-regional trade. In this research the author used gravity trade model to explain the causal relationship between dependent variable trade flows and several independent variables applying with five categories cultural goods which classified in HS codes. Firstly for cultural heritage trade flow, the results indicated that economic masses of bilateral countries have no significant influences on it; GDP per capita of host country and adjacency factor with partner country have significant negative influences on it; Internet coverage ratio has improved cultural heritages exchanges in East Asian regions. Secondly for printed matter cultural goods trade flow, the distance factor has significant negative influence but common language has significant positive influence on it. Thirdly for recorded media cultural goods, only economic masses and GDP per capita of bilateral countries can improved their trade flows. Fourthly for visual arts cultural products trade flows, almost all variables we tested have significant influences on it. Fifthly for cinema photography cultural goods trade flow, the influenced factor are same with cultural heritage products except they have strong positive interaction relationship with economic masses and common language. At last, the paper figured out some important and potential sectors for cultural goods trade in East Asia and gave some suggestions to government and cultural goods product enterprises.

• 한국기후변화학회지
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• 제6권4호
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• pp.389-397
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• 2015

The changes in the teleconnection associated with El Nin?o-Southern Oscillation (ENSO) over the East Asia and North Pacific under greenhouse warming are analyzed herein by comparing the Historical run (1970/1971~1999/2000) and the Representative Concentration Pathway (RCP) 4.5 run with 31 climate models, participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5). It is found that CMIP5 models have diverse systematic errors in simulating the ENSO teleconnection pattern from model to model. Therefore, we select 21 models based on the models' performance in simulating teleconnection pattern in the present climate. It is shown that CMIP5 models tend to project an overall weaker teleconnection pattern associated with ENSO over East Asia in the future climate than that in the present climate. It can be also noted that the cyclonic flow over the North Pacific is weakened and shifted eastward. However, uncertainties for the ENSO teleconnection changes still exist, suggesting that much consistent agreements on this future teleconnections associated with ENSO should be taken in a further study.

• 한국해안해양공학회지
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• 제4권1호
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• pp.45-58
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• 1992

황해 및 동중국해에서 기상학적으로 유발된 연여균 및 계절적 해류 순환을 산정하기 위해 3次元 수치모형이 이용되었는데 수치모형은 불규칙한 연안경계와 실제 수심을 반영할 수 있도록 구성되었다. 본 연구에서는 전회의 동중국해의 3차원 수치모형 (Choi, 1984)을 제붕역에서의 흐름을 좀더 자세히 재현할 수 있도록 세분화하였는데 모형에 사용된 유한격자체계의 해상도는 위도 4분과 경도 5분으로 구성되었으며 황해 및 동중국해상에서 유속의 3차원적 순환 형태가 산정되어 제시되었다. 수치모형에 의해 계산된 기상학적으로 유발된 恒流 유원은 이 해역의 여러 영역에서 수심(표면, 중간수심, 바닥)別 및 전체 水柱에 대해 해수 문체시간을 계산하는데 이용되었다.

• 대한한의학회지
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• 제27권4호
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• pp.62-73
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• 2006

Objective : This study aimed to investigate the effect of SHD on myelosuppression using an animal model for therapeutic evidence supporting clinical positive results. Methods : After determining the optimal concentration of 5-FU as 300 mg/kg for developing the mouse model, ICR mice or BALB/c mice were administered with SHD, and several blood parameters, including hematopoietic cytokines, colony forming activity and histological findings, were examined to evaluate the effects. Results : SHD restored the WBC and hemoglobin, and showed effects on maintaining body weight, producing GM-CSF and IL-3 and stem cell colony forming activity in accordance with histological relative entirety on bone marrow. Conclusion : SHD is an herbal drug having therapeutic effects on myelosuppression. Thus, it could be prescribed to cancer patients undergoing chemo-therapies or radio-therapies in the process of cancer treatment.

• KDI Journal of Economic Policy
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• 제33권4호
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• pp.27-48
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• 2011

본 연구는 주가지수를 경제적 척도로 삼아 동아시아의 글로벌 및 역내 통합의 정도를 검토하였다. 주가에 대한 충격을 글로벌 충격, 역내 충격 및 개별 국가 충격으로 분해하고 구조적 VAR 모형을 사용하여 이들 충격이 동아시아 국가들의 주가 변동에 미친 영향을 살펴본 결과, 1997년 금융위기 이후 점차 축소되는 추세이나 개별 국가 충격이 여전히 가장 주도적인 역할을 하는 것으로 나타났다. 반면에 글로벌 및 역내 충격은 대부분의 동아시아 국가에서 그 비중이 점차 확대되는 추세이나 영향력은 그리 크지 않았다. 본고의 분석 결과는 최근의 자유화 및 역내 통합 진전에도 불구하고 동아시아 국가들은 아직까지 상호 이질적이며 유럽 국가에 비해 비대칭적인 충격에 더 크게 노출되었음을 의미한다.

• International Journal of Naval Architecture and Ocean Engineering
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• 제11권1호
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• pp.353-363
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• 2019

This paper presents a comprehensive simulation and assessment of gas dispersion above sea from a subsea release using a Computational Fluid Dynamics (CFD) approach. A 3D CFD model is established to evaluate the behavior of flammable gas above sea, and a jack-up drilling platform is included to illustrate the effect of flammable gas cloud on surface vessels. The simulations include a matrix of scenarios for different surface release rates, distances between surface gas pool and offshore platform, and wind speeds. Based on the established model, the development process of flammable gas cloud above sea is predicted, and the dangerous area generated on offshore platform is assessed. Additionally, the effect of some critical factors on flammable gas dispersion behavior is analyzed. The simulations produce some useful outputs including the detailed parameters of flammable gas cloud and the dangerous area on offshore platform, which are expected to give an educational reference for conducting a prior risk assessment and contingency planning.

• Ocean and Polar Research
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• 제34권4호
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• pp.403-411
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• 2012

Among others, a question that has long been unanswered is why the seasonal variation of volume transport is larger in the Soya and Korea/Tsushima Straits than in the Tsugaru Strait. An attempt is made to answer this question in terms of the island rule with friction being taken into account. The problem is idealized as a simple model. The model results indicate that volume transport through a channel is determined not only by the circulation created around the adjacent island but also by those created around the neighboring islands farther away. The latter is due to the presence of bottom friction in the channels. The volume transports through the Korea/Tsushima, Tsugaru and Soya Straits estimated from the model using observed wind data show the general pattern of observed seasonality, although they contain large errors associated with the uncertain frictional parameter employed in the model. The model indicates that the observed seasonality arises essentially from the fact that wind stress curl changes its sign, from negative in the summer to positive in winter, following a large fluctuation of zero-stress curl latitude east of Hokkaido.

• Ocean Science Journal
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• 제41권4호
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• pp.235-244
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• 2006

Determining 'photosynthetically active radiation' (PAR) is a key part of calculating phytoplankton productivity in a biogeochemical model. We explore the daily and seasonal variability in the ratio of PAR irradiance to total irradiance that occurred at Ieodo Ocean Research Station (IORS) in the East China Sea under clear-sky conditions in 2004 using a simple radiative transfer model (RTM). Meteorological data observed at IORS and aerosol optical properties derived from Aerosol Robotic Network observations at Gosan are used for the RTM. Preliminary results suggest that the use of simple PAR irradiance-ratio values is appropriate in calculating phytoplankton productivity as follows: an average of $0.44\;({\pm}0.01)$ in January to an average of $0.48\;({\pm}0.01)$ in July, with average daily variabilities over these periods of about $0.016\;({\pm}0.008)$ and $0.025\;({\pm}0.008)$, respectively. The model experiments demonstrate that variations in the major controlling input parameters (i.e. solar zenith angle, precipitable water vapor and aerosol optical thickness) cause PAR irradiance ratio variation at daily and seasonal timescales. Further, increases (>0.012) in the PAR irradiance ratio just below the sea-surface are positively correlated with high solar zenith angles and strong wind stresses relative to those just above the sea-surface.

• 한국수산과학회지
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• 제36권2호
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• pp.178-186
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• 2003

Seasonal variation of phytoplankton was investigated with surface mixed layer ecosystem model in the East Sea. The model consisted of four compartments (phytoplankton, zooplankton, nutrient, detritus) forced by mixed layer depths, photosynthetically available radiation and nutrient concentrations. From model results we estimated entrainment rate $2.5-4.0\;m{\cdot}day^{-1}$ to reproduce the two annual blooms, and reproduced seasonal variation of phytoplankton at southern and northern regions by the difference of surface winter mixed layer depth (MLD) using the entrainment rate value $3.0\;m{\cdot}day^{-1}$. The spring blooms in the southern and northern regions closely related to deepening of a winter surface MLD. In the southern region where MLD was shallow and phytoplankton spring bloom occurs one month in advance to the northern region where MLD was deep. The amount of light increases within the MLD during the onset of stratification and water temperature increases faster in spring in the southern region than the northern region. Decrease of phytoplankton was mainly affected by zooplankton grazing in the southern region and by nutrient exhaustion in the northern region. The fall bloom in the two regions was caused by the nutrient availability and entrainment on the phytoplankton.