• Title/Summary/Keyword: 천수만

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Ecological variations of macrobenthos in subtidal at Chonsu bay in Chungcheongnam-do, Korea (천수만 조하대에 서식하는 대형저서동물의 생태학적 변화 연구)

  • Han, Hyoung-Sum;Ma, Chae-Woo;Choi, Man-Sik
    • Korean Journal of Environment and Ecology
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    • v.29 no.3
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    • pp.421-430
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    • 2015
  • This study was carried out to understand the ecological variations of macrobenthos communities by construction dikes in the subtidal zone of Chonsu Bay. This study analyzed the distribution of benthos, the dominant species, spatial and temporal changes of benthos communities and benthic pollutions in the subtidal zone of Chonsu Bay. A total of 252 species of subtidal macrobenthos with a density of $681ind./m^2$ were studied. In all the seasons, the species diversity was found to be higher near the mouth of the bay. For all the seasons of the year, Lumbrineris japonica was found to be the most dominant species. These dominant species were found to have positive correlations with species diversity and sedimentary parameters such as organic content in sediments. Dominant species of benthos as well as species composition and diversity showed spatial and temporal distribution patterns.Benthic Pollution Index (BPI) values estimated for the stations near the embankment were in the 4~5 levels, which indicates that the organic matter has been polluted. And as for the stations near the mouth of the bay, the BPI values were in the 1~3 levels, which indicates that the organic matter has been relatively less polluted. According to the SAB-curve analysis, the number of transitional point stations became less in the mouth of the bay.

Water Chemistry and Age Dating of Springwater in Cheju Island (제주도 용천수의 수질 화학적 특성과 연대 측정에 관한 연구)

  • Kim Jong-Hun;Ahn Jong-Sung
    • Journal of the Korean Chemical Society
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    • v.36 no.5
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    • pp.727-737
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    • 1992
  • The water chemical characteristics and age dating of springwater in Cheju island had been investigated. C_1, C_4, C_7, C_9 springwaters were not affected by seawater intrusion by TDS and electrical conductivity, relationship of Cl and tritium, Cl and HCO_3 ratio, and total hardness and pseudo hardness. In this case only C_7 springwater was evaluated tasty and healthy mineral springwater by Hahimoto's Mineral Balance Index. On the basis of the mean tritium content of rainfalls and springwater, the average residence time of it, were calculated. Considering the hydrogeologic and hydrochemical condition, completely mixed model seems to be very fit. It was obtained the result that C_9 group springwater (C_{10}, C_{12}, C_{14}) was 1.2 months, C_7 springwater was 5.6 months, and deep groundwater C_{17} was 4 years.

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Numerical Simulation of Shallow Water Flow Using Multi-dimensional Limiting Process (MLP) (MLP기법을 적용한 천수흐름의 수치모의)

  • An, Hyunuk;Yu, Soonyoung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.2B
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    • pp.123-130
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    • 2012
  • MLP (Multi dimensional Limiting Process) is implemented to simulate shallow water flows, and its performance over conventional TVD limiters in multidimensional flows is verified through several numerical simulations. MLP was developed to control oscillations for multi-dimensional compressible flows and proved to improve accuracy, efficiency and robustness in compressible flows. In this study, we applies MLP to modeling shallow water equations(SWEs) given that the SWEs are amenable to be solved using the large range of numerical methods developed to deal with compressible flows and MLP has been yet used for SWEs. Simulation results through the benchmark tests show that MLP has favorable features such as numerical oscillation control and convergence behaviors comparable to the conventional limiters. Both numerical accuracy and stability are improved in multi-dimensional discontinuous flows.

The Comparison and Analysis of Commentaries about Eokbu theory of Jeokcheonsu (『적천수(滴天髓)』 억부론 평주의 비교분석)

  • Yi, Bo-young
    • Industry Promotion Research
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    • v.7 no.1
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    • pp.89-93
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    • 2022
  • This study used a method of comparing and analyzing various editions of Jeokcheonsu, and aims to confirm why different views have arisen on commentaries that differ according to the perspective of one original text, which interpretation is more valid among them. It is not easy to grasp the theories of Myeongri because Jeokcheonsu is composed of the sentences of Si-bu with being well refined and having hidden meaning. Various perspectives makes the people more confused in reading commentaries. Lim Cheol-cho make additional annotations and try to subdivide the contents of Jeokcheonsu and classify them with quoting lots of 512 exemplifications in Ming Dynasty, and it is his great contribution to the Myeongri theory. The perspective that 'Eokbu Theory' is core contents of Myeongri theory in the first half of Jeokcheonsu is predominate. The sentence that 'Eokbu Theory' is mentioned for the first time is 'Cheayong, and we can quote 'Jeongsin', 'Soewang' and 'Junghwa' as a sentence paired together.'Eokbu Theory' of Jeokcheonsu is discussed continuously in the 'Gangyou' 'Junggwa' of Myeongri particulars which is connected in the middle of Jeokcheonsu.

Relative Significance of nanoplankton in Chonsu Bay: Species Composition, Abundance, Chlorophyll and Primary Productivity (천수만 미세플랑크톤의 상대적 중요성 : 종조성, 개체수, 클로로필 및 일차생산력)

  • 신윤근;심재형
    • 한국해양학회지
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    • v.25 no.4
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    • pp.217-228
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    • 1990
  • In order to study on the relative significance of nanoplankton in Chonsu Bay, nanoplankton samples were collected and analyzed monthly from September, 1985 to August, 1986. A total of 33 taxa representing 6 phyla, 8 classes, 13 orders, 17 families, 25 genera, 33 species have been identified. Micromonas pusilla, Pedinomonas mikron, Pyramimonas grosii, Chroomonas lateralis, Pyrenomonas salina (=Chromonas salina), chroomonas sp., Cyclotella sp., Gonyaulax sp., unidentified sphericl monads (2-5um and 6-8um in size), and unidentified naviculiod form were common species. the distribution of nanoplankton standing crops showed a great temporal and spartial variations. Nanoplankton standing crops was highest in October, 1985 and lowest in September, 1985. The abundance of nanoplankton in Chonsu Bay may be within the range of that of most coastal areas. Unidentified spherical monada (2-5um and 6-8um in size) were most dominant. Chlorophyll-a concentrations of nanoplankton ranged from 0.81 to 4.78ug/l and daily primary productivity by nanoplankton, 16.4 to 767.2 mgC/m$^2$/day. Nanofraction of total phytoplankton cell number accounted for 38% to 93% (average 6%), chlorophyll-a and primary productivity of nanoplankton 25 to 87% (average 64%) and 9 to 87% (average 53%), respectively. The results implied that nanoplankton could be a considerable contribution to phytoplankton biomass and primary productivity in Chonsu Bay phytoplankton community.

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닭고기 포장유통 세부지침 살펴보기-유럽의 도계장 및 닭고기 포장시설 시찰

  • Kim, Han-Ung
    • Monthly Korean Chicken
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    • s.138
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    • pp.73-76
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    • 2006
  • 본회는 지난달 12일부터 19일까지 5박7일의 일정으로 한형석 본회 회장을 단장으로 네덜란드, 벨기에, 독일 등 3개국의 도계 및 닭고기 포장시설을 시찰했다. 총 22명으로 구성된 이번 시찰단은 닭고기 포장유통 의무화에 맞춰 정형화된 외국의 시설을 둘러보기 위해 마련되었으며 도계 및 포장기계 설비회사인 Meyn社, Systemate社, 그리고 Stork社의 도움으로 진행되었다. 닭고기 포장유통은 단순히 포장으로만 진행되는 것이 아니라 사전준비 작업인 칠링(닭고기의 온도를 낮추는 시설)의 중요성이 대두되면서 포장시설과 함께 도계시설을 중점적으로 점검하게 되었으며 이와 함께 부분육 가공공장도 둘러볼 기회를 가지게 됐다. 이번에 방문한 도계장은 모두 에어칠링 시스템을 갖춘 곳이며, 도계장에 대한 전문지식이 부족하여 간략하게 방문한 회사의 개요만 설명하고자 한다. 처음 방문한 도계장은‘Clazing’이라는 회사로 시간당 1만5천수를 작업하는 규모이다. 작업물량은 2㎏ 이상의 산란 노계전문처리장이며 닭을 부위별로 절단∙처리하는 컷업전문 처리장이다. Flandrex 도계장 역시 노계전문 처리장으로 닭을 부위별로 분할, 아프리카 등지로 수출을 하고 있으며 시간당 9천수 정도를 작업한다.‘Klaassen푸드’는 2000년도에 세워진 도계장으로 시간당 9천수를 작업하며 부분육을 생산 벌크로 포장하여 주로 도매상중 원료육 취급업자에게 공급하고 있다. ‘Broviand社’는 닭가슴살 등을 전문으로 발골하는 회사로 시간당 6천수를 발골하며 햄버거 패티 등 가공원료로 전량 납품하고 있다. 앞서 소개한 Clazing社등에서 분할된 부분육을 발골하는 것으로 보여졌다.‘Flschgefluge社’는 독일에 위치한 회사로 원래는 사료회사를 운영하다가 도계장을 하게 된 경우로 수평계열화체계를 갖추고 있는 것으로 보인다. 시간당 1만2천수를 작업하며 95%를 부분육으로 생산, 전량 포장하여 마트 등으로 유통시키고 있다.

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A Study on the Safe Manoeuvring of Ships Navigating in Shallow Water under Strong Environmental Forces (천수역에서 외력하에 근접 항행중인 선박의 안전조선에 관한 연구)

  • Lee, Chun-Ki
    • Journal of Navigation and Port Research
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    • v.34 no.10
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    • pp.735-740
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    • 2010
  • This paper focuses on the effects of hydrodynamic forces between overtaking and overtaken vessels moving under the influences of external forces, such as strong wind and current in shallow water, in which condition the ship handling may become very complex. The purpose of this paper is to develop a guideline for safe conducting distance between two ships according to the velocity and the significance of external disturbances.

Safety Analysis of Nuclear Power Plant against Tsunami (지진해일에 대한 원자력발전소의 안전성 검토)

  • Kim, Jae Hong;Jin, So Byeom;Cho, Yong Sik
    • Proceedings of the Korea Water Resources Association Conference
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    • 2004.05b
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    • pp.1450-1453
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    • 2004
  • 최근 4년간 한반도 근해에서는 53회 이상의 해저지진이 발생하고 있다. 지진해일은 천수효과로 인해 대규모 범람을 일으켜 많은 인명 및 재산피해를 초래할 수 있다. 그 중에서도 원자력발전소의 지진해일에 대한 안전성은 필수적으로 검증되어야한다. 본 연구에서는 Bousssinesq 방정성과 천수방정식을 이용하여 지진해일의 거동을 수치해석하며, 격자 간격과 계산 시간 간격의 세분화에 의한 누적오차를 줄이기 위해 다중격자 연결모형을 이용한다.

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