• Title/Summary/Keyword: southeastern Korea

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Study on planetary boundary layer schemes suitable for simulation of sea surface wind in the southeastern coastal area, Korea (한반도 남동해안 해상풍 모의에 적합한 경계층 물리방안 연구)

  • Kim Yoo-Keun;Jeong Ju-Hee;Bae Joo-Hyun;Song Sang-Keun;Seo Jang-Won
    • Journal of Environmental Science International
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    • v.14 no.11
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    • pp.1015-1026
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    • 2005
  • The southeastern coastal area of the Korean peninsula has a complex terrain including an irregular coastline and moderately high mountains. This implies that mesoscale circulations such as mountain-valley breeze and land-sea breeze can play an important role in wind field and ocean forcing. In this study, to improve the accuracy of complex coastal rind field(surface wind and sea surface wind), we carried out the sensitivity experiments based on PBL schemes in PSU/NCAR Mesoscale Model (MM5), which is being used in the operational system at Korea Meteorological Administration. Four widely used PBL parameterization schemes in sensitivity experiments were chosen: Medium-Range Forecast (MRF), High-resolution Blackadar, Eta, and Gayno-Seaman scheme. Thereafter, case(2004. 8. 26 - 8. 27) of weak-gradient flows was simulated, and the time series and the vertical profiles of the simulated wind speed and wind direction were compared with those of hourly surface observations (AWS, BUOY) and QuikSCAT data. In the simulated results, the strength of rind speed of all schemes was overestimated in complex coastal regions, while that of about four different schemes was underestimated in islands and over the sea. Sea surface wind using the Eta scheme showed the highest wind speed over the sea and its distribution was similar to the observational data. Horizontal distribution of the simulated wind direction was very similar to that of real observational data in case of all schemes. Simulated and observed vertical distribution of wind field was also similar under boundary layer(about 1 km), however the simulated wind speed was underestimated in upper layer.

Utilization of Energy in the Sea Water of the Southeastern Yellow Sea (한국남서해의 열 에너지 이용)

  • 장선덕
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.14 no.2
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    • pp.113-116
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    • 1978
  • To ascertain the feasibility of the energy utilization in the sea adjacent to Korea, the distribution of the vertical temperature difference and the seasonal variation in the southeastern Yellow Sea are studied in relation to the sea water circulation. In summer, a region of high vertical temperature difference of approximately 16$^{\circ}C$ was found at a distance of approximately 40 miles from the western coast of Korea. It is located at the west of 125${\circ}$ 30`E and at the north of 34${\circ}$N. The vertical temperature structure is sustained by the inflow of Yellow Sea Warm Current water, the warming of the surface water of the Yellow Sea and the periodical renewal of the Yellow Sea Cold Water. It may be stated that power can be obtained from the sea water by making the use of the temperature difference. The vertical temperature difference was around 14$^{\circ}C$ in the western and southern waters of Jejudo Island. The vertical temperature difference decreases in autumn, and disappears due chiefly to the vigorous convective vertical mixing in winter when the northwest monsoon prevails. The power can be obtained from sea throughout the year, if power generation by the temperature difference is combined with that by wind and wave, and systemized in such a way that the former is employed in the hot season of summer, while the latter in winter and spring.

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THE FLUCTUATION OF THE THERMAL FRONT IN THE SOUTHEASTERN AREA OFF KOREA (한국 남동 해역에 있어서 수온전선의 변동에 관한 연구)

  • An, Hui Soo;Chung, Jong Yul
    • 한국해양학회지
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    • v.17 no.2
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    • pp.33-40
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    • 1982
  • The oceanographical condition of the southeastern area off Korea is inverestigated in the point of view of the fluctuation of the thermal front. although the fearure of the front is somewhat complicate, it can be classified intl three types. the first type is elongated toward north with the narrow cold water belt inside the front. The second type is almost parallel with the latitude of 36 N and the third type is the irregular one in which the cyclonic cold water mass and the anticyclonic warm water mass develop equally. The north-south directed fronts are strengthened either by the supply of the warm Daema Current (Tsushima Current in Japanese) of by the appearance of the cold North Korean Water along the coast. In the first type the thermocline inclines up toward the coast when the southward component of the wind is weakened. On the other hand, in the second typr the homogeneous and medium warm water spreads up to the coast and the latitude of 36 N, the second type front is formed.

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The Contents Of Heavy Metals In Sediments From The Southeastern Coastal Area Of Korea (한국 남해동부연안 해저퇴적물중의 중금속 함량에 관한 연구)

  • Lee, Dong Soo;Han, Sang Joon
    • 한국해양학회지
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    • v.13 no.2
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    • pp.11-16
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    • 1978
  • The contents of heavy metals were studied on sediments collected from the southeastern coastal area of Korea.Concentrations of the elements showed Cu 14∼ 48ppm (av. 18ppm), Pb 14∼49ppm (av. 28ppm), Zn 79∼187ppm (av. 11ppm), Co 11∼ 15ppm (av. 13ppm), Ni 22∼32ppm (av. 29ppm), Fe 3.1∼5.3% (av. 4.3%) and Mn 333 ∼1010ppm (av. 499ppm). When these values are compared with those of the unpolluted near-shore sediments from other countries,there seems to be little environmental contamination of heavy metals in the sediments of the study area. However, from the fact that the nearer to harbor the stations are, the higher the contents of copper, lead and zinc are in the sea off Pusan Bay, it is suggested that heavy metals in the sediments are starting to show some contamination from man's activities.

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Geology and Mineralization in Constancia Porphyry Cu-Mo Mine, Cusco State, Southeastern Peru (페루 남동부 쿠스코주 콘스탄시아 반암동-몰리브데늄 광산의 지질 및 광화작용)

  • Yang, Seok-Jun;Heo, Chul-ho
    • Economic and Environmental Geology
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    • v.49 no.3
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    • pp.193-199
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    • 2016
  • Constancia mine is a deposit developed within Andahuaylas-Yauri Cu-Mo-Au metallogenic belt, southeastern Peru and is located in the southwestern part of Abancay deformation zone structurally as the porphyry copper deposit type. Mineralized zone in Constancia mine are composed of leached zone, secondary enrichment zone(ca. 1% Cu), mixed zone, primary mineralized zone(ca. 0.5%), skarn zone(ca. 1.5% Cu) from the upper part. Main country rock is monzonitic porphyry. Leached zone are characterized by the precipitation of limonite and looks brown in the outcrop. Oxidized zone have green due to the occurrence of copper oxide and secondary enrichment zone are characterized by the occurrence of chalcocite. Skarn zone are characterized by the occurrence of magnetite and garnet. Now, Hudbay, Canadian mining company, have 100% share about Constancia mine and started to produce commercially from January, 2015.

Petrography of the Miocene Volcanic Rocks of the Eoil Basin, Southeastern Part of Korean Peninsula (한반도 남동부 어일분지의 마이오세 화산암의 암석기재적 연구)

  • 이정현;윤성효;고정선
    • The Journal of the Petrological Society of Korea
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    • v.13 no.2
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    • pp.64-80
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    • 2004
  • The Miocene volcanic rocks in the Eoil Basin, which is one of the pull-apart basins in the southeastern Korean Peninsula, are bimodal in composition: felsic (67.2-70.5wt.% SiO$_2$) and mafic(49.3-55.2wt.% SiO$_2$). The bimodal volcanic activities in the basin appear to be closely associated with the basin development. The volcanic rocks are intercalated with thick Files of sedimentary sequence. They show evidence of magma mixing. which has produced mafic and felsic volcanic rocks. We are able to identify the petrographic characteristics (disequilibrium phenocryst assemblages) of the volcanic rocks that were mixed. In basaltic lava, phenocrysts of olivine and orthopyroxene coexist with corroded quartz phenocryst. Dacitic to rhyolitic welded ash-flow tuff contains phenocrysts of clinopyroxene and orthopyroxene. It suggests that phenocryst disequilibrium have been affected and mixed by magmas, which have different compositions.

The Examination of the Limitations of Using the OSL Dates Derived from this Study in the Correlation of MIS 5 Marine Terraces Distributed in the Southeastern Coast of the Korean Peninsula (한반도 남동부 해안 해성단구의 분류와 편년에 있어서 본 연구에서 도출된 OSL 연대 적용의 한계성 검토)

  • Choi, Seong Gil;Tamura, Toshikazu;Miyauchi, Takahiro;Tsukamoto, Sumiko
    • Journal of The Geomorphological Association of Korea
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    • v.25 no.4
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    • pp.63-75
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    • 2018
  • The lower marine terrace 1 and 2 surfaces distributed between Ulsan and Pohang coast in the southeastern coast of the Korean penninsula have been correlated with MIS 5e and 5a (or 5c) by amino acid dates, 14C dates, wide-spread tephra correlation and pollen analysis respectively. In this study, to test the reliability of the OSL method for the estimation of the numerical burial age of marine sediment deposits, we analyzed the samples from the marine terraces which have been known as typical marine terraces formed during MIS 5e and MIS 5a in the above-mentioned coast. The burial ages of the marine deposit of the lower marine terrace 1 and 2, with paleoshoreline altitudes of 18m to 19m and 10m to 11m respectively, both showed about the same age of 60 ka BP. The lower marine terraces 1 and 2, however, were divided into two terrace surfaces by a clear terrace cliff. Besides, the OSL dates of the lower and upper parts of the lower marine terrace 2 of the Bonggil coast showed the reversed burial ages. In the lower marine terrace 1 of the Sanhari coast, almost the same burial ages were derived from both the lower part (marine rounded gravel layer) and the upper part (terrestrial angular gravel layer) of the terrace deposit. Therefore, at the present time, judging from only the OSL dates measured in this study, it could be argued that the OSL method is not the best for the estimation of forming periods of the lower marine terraces 1 and 2 and their classification.

The Spatial Construction of Conflicts : The Politics of Scales in the Conflicts over "Southeastern New International Airport" in Korea (갈등의 공간적 구성: 동남권 신공항을 둘러싼 스케일의 정치)

  • Lee, Jin-Soo;Lee, Hyeok-Jae;Jo, Gyu-Hye;Chi, Sang-Hyun
    • Journal of the Korean association of regional geographers
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    • v.21 no.3
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    • pp.474-488
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    • 2015
  • Conflicts in the construction of large public facilities carried out as national projects are crucial issues we have to deal with. There are growing concerns for and oppositions to large construction projects in terms of environmental deterioration and the dissolution of local communities. In the case of projects that promise the creation of jobs and investment, the competition and disputes are increasing and being intensified. Therefore, there is a considerable amount of study on the competitions and conflicts between regions. Previous studies have focused on the procedures of public policy, governance structure, the role of local media. Contrary to the previous studies, this study investigates the spatial ways of constructing conflicts. Based on the analysis of the project of "Southeastern New International Airport", there is a mismatch between the spatial boundary of cost/benefit and agents (regions) of disputes. The agents of conflicts also show the politics of multiple scales by constructing alliances and breaking the network in the process of the airport project. The findings suggest that the conflicts on regional development should be understood as the construction of dynamic regional politics on regional development rather than as the by-product in the practice of policies.

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Seasonal and Spatial Variation of Polychaetous Community in Youngil Bay, Southeastern Korea (영일만 다모류 군집의 계절별, 공간적 변화)

  • 신현출;최성순
    • 한국해양학회지
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    • v.27 no.1
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    • pp.46-54
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    • 1992
  • An investigation on the benthic polychaete community in Youngil Bay was conducted during four seasons of 1991. Polychaetes. the dominant macrofaunal group occupying 71.3% in total macro-faunal density, comprised a total of 72 species with a mean density of 1,485 indiv. m/SUP -2/. The highest species number of 54 spp. and density of 3,207 undiv. m/SUP -2/ was recorded in summer, while the lowest in autumn. The most abundant species was Spiophanes nombyx (37.5%), followed by Pseudopolydora sp.(8.4%), Lumbrineris longifolia(7.0%), Madden cristata(6.5%), Polydora ciliata(4.9%) and so on. Maldane cristata was dominated in winter, Polydora ciliata in spring and Spiophanes bombyx in summer and autumn. The density and species number of Polychaetes were high in the southeastern area of Youngil Bay, and poor near the mouth of Hyoungsan River. Based on the species composition, study area was divided into three regions. Each region sustained its specific benthic faunal assemblage; Maldane-Praxillella assemblage from the middle to the southeastern region of Youngil Bay, Spiophanes-Nephtys assemblage in the northwestern region, and Pseudopolydora-Polydora-Capitella assemblage from the mouth of Hyoungsan River to Pohang Hobour. Maldane Praxillella assemblage showed the highest species number of 55 spp.. and the highest species diversity and species richness indices. Spiophanes-Nephtys assemblage had the highest density of 2,675 indiv. m/SUP -2/ and the highest dominance index because of the predominance of Spiophanes bombyx with a density of 2,073 indiv. m/SUP -2/. Pseudopolydora-Polydora-Capitella assemblage was found in the polluted area and it was a specific assemblage mainly composed of the dominance of organic pollution indicator species. The dominant Polychaetes were Pseudopolydora sp., Polydora ciliata, Capitella capitata, and Dorvillea sp.

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Species classification of the toxic dinoflagellate Alexandrium tamarense and A. catenella based on their paralytic shellfish toxin profiles

  • Kim, Young-Soo;Kim, Chang-Hoon
    • Proceedings of the Korean Aquaculture Society Conference
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    • 2003.10a
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    • pp.128-128
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    • 2003
  • The annually outbreak of paralytic shellfish poisoning (PSP) were caused by toxic dinolagellate A. tamarense and A. catenella in Korea. The purpose of this study were to investigate the distribution of PSP-causative organisms, A. tamarense and A. catenella and their species classification. Sediment (Saemangeum, the south open sea) and water samples (southeastern coast) were sampled to establish clonal isolates in 2003. After isolation and purification, strains were cultured under $17^{\circ}C$, f/2 media, 14:10=L:D cycle. PST analysis and species identification were performed by HPLC-FD method and specific DNA probe, respectively. Thirty-ons strains were isolated from the Saemangeum reclamation, southeastern coast including Jinhae Bay and south open sea. PSTs were detected in all cultured strains. In eight strains from south offshore, major toxin components are GTX5, C1/2 and minors are GTX3/4, dcGTX3, neoSTX. Sixteen strains from south coastal area have GTX1/4, neoSTX, C1/2 as major toxin components and GTX2/3 as minors. Seven strains from the Saemangeum reclamation have GTX5, C1/2 as major toxin components and GTX1/2/3/4 as minors. Thus, among eight south offshore isolates, four A. tamarense have more toxic (38.31~l19.16 fmol.$cell^{-1}$) than A. catenella (3.78~13.13 fmol.$cell^{-1}$). With the previous results of different toxin composition, toxin components and toxin contents, .it is toxin profile that could used to diagnosis of regional toxic population and geographical distribution of both A. tamarense and A. catenella and their toxigenic strains.

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