• 수산해양기술연구
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• 제55권3호
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• pp.252-263
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• 2019

In order to understand the tidal current and mean flow at the west channel of Yeoja Bay in the South Sea of Korea, numerical model experiments and vorticity analysis were carried out. The currents flow north at flood and south at ebb respectively and have the reversing form in the west channel. Topographical eddies are found in the surroundings of Dunbyong Island in the east of the channel. The flood currents flow from the waters near Naro Islands through the west channel and the coastal waters near Geumo Islands through the east channel. The ebb currents from the Yeoja Bay flow out along the west and the east channels separately. The south of Nang Island have weak flows because the island is located in the rear of main tidal stream. Currents are converged at ebb and diverged at flood in the northwest of Jeokgum Island. Tidal current ellipses show reversing form in the west channel but a kind of rotational form in the east channel. As the results of tide induced mean flows, cyclonic and anticyclonic topographical eddies at the northern tip but eddies with opposite spin at the southern tip are found in the west channel of Yeoja Bay. The topographical eddies around the islands and narrow channels are created from the vorticity formed at the land shore by the friction between tidal currents and the west channel.

• Advances in Energy Research
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• 제5권4호
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• pp.305-320
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• 2017

Limited quantity and non-uniform distribution of fossil fuel over the world, along with the environmental concerns of increasing $CO_2$ emissions, indicate that gradual and planned switchover to the sustainable energy sources is the need of the day. Ocean energy is well-distributed over the coasts, abundant, renewable and available in the form of wave energy, tidal energy and thermal energy. India has gathered precious experience from the pilot plants utilizing these methods over the last few years. One of the main constraints is deemed to be the grid connectivity. Time has come to transform this limitation into opportunity. Ocean power can be a very suitable option for the coastal belts and the islands. Implementation of this concept would require large-scale industry participation along with favourable government policies in the coming years. This article attempts a review of the ocean energy initiatives in India and proposes a roadmap for the future.

• The Korean Journal of Ecology
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• 제7권3호
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• pp.158-169
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• 1983

An investigation on the floras of Osik island and its neighboring two islands, 13km west of Gunsan, showed that there were a total of 305 kinds belonging to 81 families, 132 genus, 259 species, 42 varieties, 4 formas. Of the 305 kinds collected 213 kinds were herb and 92 kinds were woody plant. Seven species of evergreen broad-leaved trees including Euonymus japonica T., Eurya japonica T. and Elaeagnus macrophylla T. etc. are listed in the Norae-sum and Ga-do. The vegetations of Norae-sum and Ga-do were more favorable than that of Osik-do which vegetation was destructed by human inerferences. Coastal plants in these areas were about 30 species. It is interest that the floras of these areas were very similar to that of Gogunsangun-do (r=0.97) inspite of adjacency to inland area.

• Journal of Ecology and Environment
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• 제33권2호
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• pp.115-120
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• 2010

The Asian cultural landscape is a mirrored ecosystem of great complexity, formed by the interaction of man and nature, coupled with a host of ecological processes. The human dependencies on and environmental adaptation of the bio-organisms and the surrounding landscape constitute the typical cultural landscape. Islands are a good example of a cultural landscape, and each mosaic pattern of marine and coastal ecosystems reflects bio-cultural diversity. Along with land-use patterns, wise use of biological organisms and indigenous knowledge has expanded to islands in the Asia-Pacific region in several ways (sea current and human impact, etc.). Loss in biodiversity and landscape diversity as well as cultural diversity owing to global warming and rapid urbanization are emerging issues for island ecosystems all over the world. In order to sustain the historical coexistence between man and natural systems, we ecologists must continue to search for a holistic solution for academic consilience. In this paper, I present the vision and practical characteristics of island ecology with a view toward the conservation of the traditional landscape and bio-cultural diversities in the seascape.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2008년도 International Symposium on Remote Sensing
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• pp.297-300
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• 2008

High-resolution mesoscale meteorological modeling requires more accurate and higher resolution digital elevation model (DEM) data. Shuttle Radar Topographic Mission (SRTM) has created 90 m DEM for entire globe and that is freely available for meteorological modeling and environmental applications. In this research, the effects of the topographic interpolation methods on high-resolution wind field simulation in the coastal regions were quantitatively analyzed using Weather Research and Forecasting (WRF) model with SRTM data. Sensitivity experiments with three different interpolation schemes (four-point bilinear, sixteen-point overlapping parabolic and nearest neighbor interpolation methods) were preformed using SRTM. In WRF modeling with sixteen-point overlapping parabolic interpolation, the coastal line and some small islands show more clearly than other cases. The maximum height of inland is around 140 meters higher, while the minimum of sea height is about 80 meter lower. As it concerns the results of each scheme it seems that the sixteen-point overlapping parabolic scheme indicates the well agreement with observed surface wind data. Consequently, topographic changes due to interpolation methods can lead to the significant influence on mesoscale wind field simulation of WRF modeling.

• 한국측량학회지
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• 제30권2호
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• pp.189-197
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• 2012

This research attempted to find possibilities of the practical use utilizing geospatial methods for the balanced promotion of sustainable coastal development and preservation through a case study of Jekyll Island, one of Georgia's barrier islands. In response, this research provided ways for practical use in sustainable development and preservation plans. First this research thoroughly investigated the 1996 master plan of Jekyll Island and tried to recalculate developed and undeveloped areas. Second, new estimations for developed areas were investigated through field survey. Third, this research proposed the use of the satellite images with different levels of spatial resolutions and tested different classification schemes to find possibilities for practical use. For these purposes, first, we classified developed and undeveloped features by manual digitization using an aerial photo image with 0.5m spatial resolution. Second, a Landsat 7 ETM+ and a QuickBird satellite images with mid- and high-levels of spatial resolutions were applied to identify developed and undeveloped areas using both the National Land Cover Data (NLCD) and the Coastal Change Analysis Program (CCAP) classification schemes. Also, GEOBIA (Geographic Object-Based Image Analysis) was conducted to accurately identify developed and undeveloped areas.

• 한국항만경제학회지
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• 제36권3호
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• pp.1-20
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• 2020

연안 여객항로는 육지와 섬지역의 연결, 섬주민의 수송수단, 섬지역 관광과 같은 역할을 수행하기 때문에 매우 중요하다. 특히 최근 국민소득의 증대, 일과 휴식이 균형 잡힌 워라벨(Work-life balance) 문화의 확산, 주 5일제 도입 등 삶의 질이 향상됨에 따라 여가문화생활인 여행에 대한 관심이 높아졌으며, 이에 섬지역에 대한 우리 국민의 관광 수요 증가하고 있다. 이러한 연안관광 환경 변화에 의해서 연안 여객터미널 이용객수가 증가함에 따라 연안 여객터미널 시설 및 서비스에 대한 중요성과 필요성이 점점 증대되고 있다. 이러한 상황에서 여객터미널 관리 조직들이 예산을 합리적으로 집행하여 여객터미널 이용객의 이용편익을 제고할 수 있도록 연안 여객터미널을 효율적으로 관리 운영할 필요가 있다 본 연구에서는 연안 여객터미널 관리·운영기관(업체)이 수익성 중심의 경영과 공공성 중심의 경영을 효율적으로 하고 있는지에 대한 평가 및 분석을 실시하였다. 연안여객 터미널의 경여 효율성 평가를 위하여 터미널의 건물 연면적, 투입인력, 예산지출 대비 이용객수와 운영수입의 관계를 분석하고, 이들 투입 및 산출변수들을 투입한 DEA분석을 통해 경영효율성을 비교 평가하였다. 분석결과, 분석결과 15개 터미널 중 인천항 제1국제, 사동항, 포항항, 목포항 제2 연안, 부산항 연안 여객터미널의 경영효율성이 떨어지는 것으로 나타났다. 전체 연안 여객터미널과 비교하여 수익성이 낮은 것으로 평가되는 8개 터미널은 섬관광 활성화와 러시아 및 일본지역 항로 개발(동해항 국제)을 통해 이용객수 증가에 따른 터미널 이용료 수입을 증대시키고, 터미널 사무실 임대 수입 및 부대사업 수입을 증대시켜 수익성을 개선하여야 할 것이다. 공익성의 경영효율성이 낮은 8개 터미널은 섬관광 홍보 및 마케팅 강화, 일본 및 중국 연안지역 관관상품 개발, 항로 개발, 초대형 쾌속선 도입 등을 통해 이용객수를 증대시켜나가야 할 것이다. 이 연구는 연안 여객터미널의 건물 연면적, 투입인력, 예산지출의 투입지표와 운영수입 및 이용객수의 산출지표를 할용하여 경영 효율성을 최초로 평가하고, 터미널의 특성을 반영하여 수익성 및 공익성의 경영효율성 개선방안을 제시하였다는 점에서 연구의 의의가 크다고 할 수 있다.

• 한국대기환경학회지
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• 제25권5호
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• pp.432-449
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• 2009

In this study, the effects of high-resolution land cover on the simulation of near-surface meteorological fields were evaluated in two different coastal regions using Weather Research and Forecasting (WRF) model. These analyses were performed using the middle classification land cover data upgraded by the Korean Ministry of Environment (KME). For the purpose of this study, two coastal areas were selected as follows: (1) the southwestern coastal (SWC) region characterized by complex shoreline and (2) the eastern coastal (EC) region described a high mountain and a simple coastline. The result showed that the application of high-resolution land cover were found to be notably distinguished between the SWC and EC regions. The land cover improvement has contributed to generate the realistic complex coastline and the distribution of small islands in the SWC region and the expansion of urban and built-up land along the sea front in the EC region, respectively. The model study indicated that the improvement of land cover caused a temperature change on wide areas of inland and nearby sea for the SWC region, and narrow areas along the coastal line for the EC region. These temperature variations in the two regions resulted in a decrease and an increase in land-breeze and sea-breeze intensity, respectively (especially the SWC region). Interestingly, the improvement of land cover can contribute large enough to change wind distributions over the sea in coastal areas.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2018년도 학술발표회
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• pp.145-145
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• 2018

Small islands rely heavily on groundwater resources in addition to rainwater as the source of freshwater since surface water bodies are often absent. The groundwater resources are vulnerable to sea level rise, coastal flooding, saltwater intrusion, irregular pattern of precipitation resulting in long droughts and flash floods. Increase in population increases the demand for the limited groundwater resources, thus aggravating the problem. In this study, the effects of climate change on Tongatapu Island, Kingdom of Tonga, a small island in Pacific Ocean, are investigated using a sharp interface transient groundwater flow model. Twenty nine downscaled General Circulation Model(GCM) predictions are input to a water balance model to estimate the groundwater recharge. The temporal variation in recharge is predicted over the period of 2010 to 2099. A set of GCM models are selected to represent the ensemble of 29 models based on cumulative recharge at the end of the century. This set of GCM model predictions are then used to simulate a total of six climate scenarios, three each (2010-2039, 2040-2069, and 2070-2099) under RCP 4.5 and RCP 8.5. The impacts of predicted climate change on groundwater resources is evaluated in terms of freshwater volume changes and saltwater ratios in pumping wells compared to present conditions. Though the cumulative recharge at the end of the century indicates a wetter climate compared to the present conditions the large variability in rainfall pattern results in frequent periods of groundwater drought leading to saltwater intrusion in pumping wells. Thus for sustaining the limited groundwater resources in small islands, implementation of timely assessment and management practices are of utmost importance.

• 자원환경지질
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• 제15권3호
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• pp.123-154
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• 1982

Petrochemical, K-Ar dating, Sand Rb/Sr isotopes, metallogenic zoning, paleomagnetic and geotectonic studies of the Gyongsang basin were carried out to examine applicability of plate tectonics to the post-late Cretaceous igneous activity and metallogeny in the southeastern part of Korean Peninsula. The results obtained are as follows: 1. Bulgugsa granitic rocks range from granite to adamellite, whose Q-Ab-Or triangular diagram indicates that the depth and pressure at which the magma consolidated increase from coast to inland varying from 6 km, 0.5-3.3 kb in the coastal area to 17 km, 0.5-10 kb in the inland area. 2. The volcanic rocks in Gyongsang basin range from andesitic to basaltic rocks, and the basaltic rocks are generally tholeiitic in the coastal area and alkali basalt in the inland area. 3. The volcanic rocks of the area have the initial ratio of Sr^{87}/Sr^{86} varying from 0.706 to 0.707 which suggests a continental origin; the ratio of Rb/Sr changing from 0.079-0.157 in the coastal area to 0.021-0.034 in the inland area suggests that the volcanism is getting younger toward coastal side, which may indicate a retreat in stage of differentiation if they were derived from a same magma. The K_2O/SiO_2 (60%) increases from about 1.0 in the coastal area to about 3.0 in the inland area, which may suggest an increase indepth of the Benioff zone, if existed, toward inland side. 4. The K-Ar ages of volcanic rocks were measured to be 79.4 m.y. near Daegu, and 61.7 m.y. near Busan indicating a southeastward decrease in age. The ages of plutonic rocks also decrease toward the same direction with 73 m.y. near Daegu, and 58 m.y. near Busan, so that the volcanism predated the plutonism by 6 m.y. in the continental interior and 4 m.y. along the coast. Such igneous activities provide a positive evidence for an applicability of plate tectonics to this area. 5. Sulfur isotope analyses of sulfide minerals from 8 mines revealed that these deposits were genetically connected with the spacially associated ingeous rocks showing relatively narrow range of ${\delta}^{34}S$ values (-0.9‰ to +7.5‰ except for +13.3 from Mulgum Mine). A sequence of metallogenic zones from the coast to the inland is delineated to be in the order of Fe-Cu zone, Cu-Pb-Zn zone, and W-Mo zone. A few porphyry type copper deposits are found in the Fe-Cu zone. These two facts enable the sequence to be comparable with that of Andean type in South America. 6. The VGP's of Cretaceous and post Cretaceous rocks from Korea are located near the ones($71^{\circ}N$, $180^{\circ}E$ and $90^{\circ}N$, $110^{\circ}E$) obtained from continents of northern hemisphere. This suggests that the Korean peninsula has been stable tectonically since Cretaceous, belonging to the Eurasian continent. 7. Different polar wandering path between Korean peninsula and Japanese islands delineates that there has been some relative movement between them. 8. The variational feature of declination of NRM toward northwestern inland side from southeastern extremity of Korean peninsula suggests that the age of rocks becomes older toward inland side. 9. The geological structure(mainly faults) and trends of lineaments interpreted from the Landsat imagery reveal that NNE-, NWW- and NEE-trends are predominant in the decreasing order of intensity. 10. The NNE-trending structures were originated by tensional and/or compressional forces, the directions of which were parallel and perpendicular respectively to the subduction boundary of the Kula plate during about 90 m.y. B.P. The NWW-trending structures were originated as shear fractures by the same compressional forces. The NEE-trending structures are considered to be priginated as tension fractures parallel to the subduction boundary of the Kula plate during about 70 m.y. B.P. when Japanese islands had drifted toward southeast leaving the Sea of Japan behind. It was clearly demonstrated by many authors that the drifting of Japanese islands was accompanied with a rotational movement of a clock-wise direction, so that it is inferred that subduction boundary had changed from NNE- to NEE-direction. A number of facts and features mentioned above provide a suite of positive evidences enabling application of plate tectonics to the late Cretaceous-early Tertiary igneous activity and metallogeny in the area. Synthesizing these facts, an arc-trench system of continental margin-type is adopted by reconstructing paleogeographic models for the evolution of Korean peninsula and Japan islands. The models involve an extention mechanism behind the are(proto-Japan), by which proto-Japan as of northeastern continuation of Gyongsang zone has been drifted rotationally toward southeast. The zone of igneous activity has also been migrated from the inland in late-Cretaceous to the peninsula margin and southwestern Japan in Tertiary.