• Title/Summary/Keyword: OCEANS

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Review of Internal Waves in Ocean (해양에서의 내부파)

  • Cho, Yong-Sik;Lee, Bong-Hee;Yoon, Tae-Hoon
    • Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
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    • 2000.09a
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    • pp.113-119
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    • 2000
  • Internal waves, including all kinds of wave phenomena inside a stratified fluid system, have been a subject of interest for a long time in geophysics, coastal and ocean engineering, applied mathematics and hydrodynamics. The vast oceans on the earth are a complex stratified fluid system widely distributed with pycnoclines, which are horizontally layered regions with a large density variation, commonly located about 50-150 meters below the ocean surface. (omitted)

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A Study in Regime for Establishing Port State Control in Korea (항만국통제의 정착을 위한 제도적 고찰)

  • 강동수
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.1 no.2
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    • pp.17-37
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    • 1995
  • Since the inception of the Paris Memorandum of Understanding 1982, Port State Control has been recognised as one of the most effective measures available to eradicate substandard shipping from the oceans of the world. This paper explains the basis, genesis and developmt of cooperative arrangements in Port State Control, and aims to suggest that Korea government and shipwoners should be ready to response to the adoption of cooperative arrangement in Port State Control of Asia-Pacific region.

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DESIGN OF THE CEMENT DEEP MIXING FOUNDATION FOR THE BUSAN-GEOJE IMMERSED TUNNEL

  • Kim, Yong-Il
    • Proceedings of the Korean Geotechical Society Conference
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    • 2010.09c
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    • pp.96-103
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    • 2010
  • The GK immersed tunnel as a part of the Busan-Geoje Fixed Link Project, introduced the immersed tunnel method into Korea for the first time. This challeging project to be completed in 2010 will open a new era to link oceans of the world with optimized design and safety for future use. The immersed tunnel method would possibly suitable for use in construction of a sub sea tunnel from Korea to Japan and from Korea to China that could potentially be built in the distant future. We hope the techniques learned from the Busan-Geoje Fixed Link Project can be applied to further projects in the near future.

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Development and Application for Ocean's Deep Water (해양심층수의 개발과 활용)

  • 진수웅
    • Journal of the Korean Professional Engineers Association
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    • v.37 no.4
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    • pp.55-59
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    • 2004
  • Exploitation of the ocean's deep water has brought humanity a wealth of treasures for centuries. Even so, it can confidently be forecast that the Ocean will be far more important to future generations than it has ever been in the past. Although many researchers endeavor to explore oceans, the ocean holds the crucial elements for maintaining a growing industrialized population in search of raw materials. This requires careful study and selection of innovations that will provide future generations and raw materials with an unlimited renewable and non-pollution energy and raw materials source with advantageous side benefits.

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Prediction of Surface Ocean $pCO_2$ from Observations of Salinity, Temperature and Nitrate: the Empirical Model Perspective

  • Lee, Hyun-Woo;Lee, Ki-Tack;Lee, Bang-Yong
    • Ocean Science Journal
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    • v.43 no.4
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    • pp.195-208
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    • 2008
  • This paper evaluates whether a thermodynamic ocean-carbon model can be used to predict the monthly mean global fields of the surface-water partial pressure of $CO_2$ ($pCO_{2SEA}$) from sea surface salinity (SSS), temperature (SST), and/or nitrate ($NO_3$) concentration using previously published regional total inorganic carbon ($C_T$) and total alkalinity ($A_T$) algorithms. The obtained $pCO_{2SEA}$ values and their amplitudes of seasonal variability are in good agreement with multi-year observations undertaken at the sites of the Bermuda Atlantic Timeseries Study (BATS) ($31^{\circ}50'N$, $60^{\circ}10'W$) and the Hawaiian Ocean Time-series (HOT) ($22^{\circ}45'N$, $158^{\circ}00'W$). By contrast, the empirical models predicted $C_T$ less accurately at the Kyodo western North Pacific Ocean Time-series (KNOT) site ($44^{\circ}N$, $155^{\circ}E$) than at the BATS and HOT sites, resulting in greater uncertainties in $pCO_{2SEA}$ predictions. Our analysis indicates that the previously published empirical $C_T$ and $A_T$ models provide reasonable predictions of seasonal variations in surface-water $pCO_{2SEA}$ within the (sub) tropical oceans based on changes in SSS and SST; however, in high-latitude oceans where ocean biology affects $C_T$ to a significant degree, improved $C_T$ algorithms are required to capture the full biological effect on $C_T$ with greater accuracy and in turn improve the accuracy of predictions of $pCO_{2SEA}$.

Effects of 4-tert-octylphenol on glutathione-related antioxidant status in olive flounder Paralichthys olivaceus

  • Jee, Jung-Hoon;Keum, Yoo-Hwa;Bae, Jun Sung;Lee, Chae Won;Yang, Chan Yeong;Choi, Sang-Hoon;Kang, Ju-Chan;Park, Kwan Ha
    • Journal of fish pathology
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    • v.32 no.2
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    • pp.113-121
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    • 2019
  • Effects on glutathione-related antioxidant parameters were examined after a chronic exposure of olive flounder, Paralichthys olivaceus to dietary 4-tert-octylphenol (4-tert-OP). Fish were fed diets containing 4-tert-OP at 0, 1, 5 and 10 mg/kg diet for 6 weeks. Antioxidant parameters examined were reduced glutathione (GSH) contents and enzyme activities of glutathione reductase (GR), glutathione S-transferase (GST) and glutathione peroxidase (GPx) in tissue homogenates of the liver, kidney and gill. It was observed that all parameters examined increased although there were some differences in dose responses and temporal patterns in the increase. GSH contents increased after exposure to 4-tert-OP in the three organs examined. However, the GSH increase was evident only after 4 weeks in the liver whereas it was elevated after 2 weeks in the kidney and gill. GR activity exhibited a significant increase in response to 4-tert-OP at 1 mg/kg in all three organs, however, its activity returned to control levels when exposed to 5 and 10 mg/kg. Hepatic GST activity showed an earlier increase at week 2 in contrast to the kidney and gill where they increased after 4 weeks of 4-tert-OP exposure. Temporal patterns in GPx activity changes to 4-tert-OP exposure were dissimilar among the organs: hepatic activity increased from week 2 through week 6; renal activity increased transiently at week 2; gill levels were higher through weeks 4 - 6. The results suggest that elevation of several GSH-related antioxidant parameters can be considered as evaluation criteria for 4-tert-OP-induced oxidative stress in a fish.

Performance Characteristics of a Mixed Refrigerant OTEC Power Cycle Using Hot Waste Water (온배수를 이용한 혼합냉매용 해양온도차 발전 사이클의 성능 특성)

  • Yoon, Jung-In;Son, Chang-Hyo;Heo, Jeong-Ho;Ye, Byoung-Hyo;Kim, Hyun-Ju;Lee, Ho-Saeng
    • Journal of Power System Engineering
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    • v.17 no.6
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    • pp.102-107
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    • 2013
  • In this paper, the performance analysis for evaporation capacity, total work and efficiency of the ocean thermal energy conversion(OTEC) power system using mixed refrigerant(R32,R152a) is conducted to find the effect of hot wasted water on OTEC power system. The system in this study is applied with two stage turbine, regenerator, cooler and separator on Organic Rankine Cycle. The commercial program HYSYS is used for the performance analysis. The main results were summarized as follows : The efficiency of the OTEC power cycle has a largely effect on the evaporation capacity and total work. As increasing temperature of heat source water, evaporator's capacity is decreased but total work increase. Otherwise, using hot wasted water bring effects not only increasing system efficiency but also declining evaporator's capacity. Thus With a thorough grasp of these effect, it is necessary to find way to use hot wasted water emitted by power plant and so on.

A Study on Navigational Support Services for Improving Navigational Safety of Non-SOLAS Ships (비협약선박의 항해안전 향상을 위한 항해지원서비스에 관한 연구)

  • An, Kwang;Kim, Inchul;Kim, Chol-Seong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.22 no.4
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    • pp.305-310
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    • 2016
  • This study identified necessary navigational support services to prevent accidents through an examination and a survey on the navigation and communication systems of non-SOLAS ships. The functional and operational requirements for the identified navigational support services were discussed accordingly. Among the navigational support services proposed are an Electronic Navigational Chart (ENC) service, a route planning service, an operation monitoring service, and collision prevention support services for ships in coastal areas. To facilitate the identified navigational support services, ship navigation system, shore supporting centre and maritime communication network were discussed as a digital infrastructure. The operational methode for the digital infrastructure were discussed in the service scenarios for ships carrying dangerous cargo, large ships over 200 meters in length and high speed passenger ships over 15 knots in speed. This study will facilitate the development of policies for the improvement of ship operation management in Korean coastal waters and will contribute to improving the navigational safety of non-SOLAS ships.

Embryonic Development of Haploid Olive Flounder Paralichthys olivaceus (반수체 넙치(Paralichthys olivaceus)의 발생학적 특성 분석)

  • Jung, Hyo Sun;Kim, Youn Kyoung;Kim, Hyun Chul;Noh, Jae-Koo;Lee, Jeong-Ho;Kim, Dong Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.48 no.5
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    • pp.696-703
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    • 2015
  • We investigated the characteristics of embryonic and abnormal organ development in haploid olive flounder, Paralichthys olivaceus, by comparing egg development and histological sections in haploid and diploid individuals. After the mid-blastula transition, abnormal development was observed in haploid fish, including delayed epiboly and malformation of the germ ring and embryonic body. In haploid flounder, Kupffer’s vesicles are irregularly shaped and of variable size compared to diploids. The embryonic body of haploids was shorter and broader than that of diploids and the tail length and size were variable. Most haploid embryos failed to hatch and the few larvae that did, did not survive for more than 6 h. The histological analysis of haploid larvae revealed deformed development in diverse organs, including the eye, otic vesicles, notochord, and neural tube. These results may be related to an abnormality in the axial system of haploid larvae. This study confirmed that the abnormalities of haploid olive flounder were similar to the reported characteristics of haploid syndrome. The abnormalities are caused by delayed epiboly and involution and deformity of Kupffer’s vesicle during egg development.