• Title/Summary/Keyword: Marine conservation

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Influence of Lubricating Oil Emulsified on the Behaviour of Cavitation Erosion - Corrosion at Bearing Metals (베어링 합금재의 캐비테이션 침식-부식거동에 미치는 유화 윤활유의 영향)

  • 임우조;이진열
    • Journal of Advanced Marine Engineering and Technology
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    • v.17 no.3
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    • pp.42-49
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    • 1993
  • Recently, because the lubricating oil showed a tendency to be emulsified and oxidized by high speed, high output and the extension of maintenance & conservation of marine engine, the cavitation erosion-corrosion at such an environment became a big problem on effective performance of engine. Therefore, there was a need to study the behavior and protection of erosion-corrosion damage, and then applied inhibitor to a protective method of cavitation erosion- corrosion damage. At this time, test environments were marine lubricating oil & various emulsified oil that mixed distilled water and sea water etc., and also used 20KHz, 24.mu.m piezoelectric vibrator as an experimental apparatus of cavitation erosion. With this apparatus, we investigated an influence of the emulsified oil on characteristics of erosion-corrosion and protection for erosion-corrosion by inhibitor at slide bearing metals.

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Environmental Evaluation of Sediment Quality for Small Scale Marine Ranch around the Gunsan Coastal Areas (군산해역에 있어서 소규모 바다목장화를 위한 해양저질 환경 평가)

  • Kim, Jong-Hwa;Kim, Jong-Kyu;Park, Byung-Soo
    • Journal of Fisheries and Marine Sciences Education
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    • v.20 no.3
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    • pp.508-519
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    • 2008
  • Hot air drying is a method that let moistures evaporate by heat exchange between heating air and dry target. This way is dominating more than about 70% of dryers that the use extent is wide fairly, and is established in domestic than dryer that use conduction or radiation etc. Most of research about drying had been emphasized in size of device through analysis for these dry phenomenon plain, heating topology, and aspect of form and so on by dry target's special quality, and research about device development or waste heat withdrawal technology in energy utilization efficiency side is slight real condition. Therefore, in this study, Investigated numerically about thermal efficiency elevation that is leaned against as that change the temperature of inlet and outlet in heat exchanger of the hot air drying tower.

A Study on the Enhancement of the Quality of Pusan Port Traffic Management Service (부산항 해상교통관제 서비스의 품질개선에 관한 연구)

  • 이은방;윤정수
    • Proceedings of KOSOMES biannual meeting
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    • 2001.05a
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    • pp.105-133
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    • 2001
  • World trade has been increasing continuously in total volume, on the other hand, environmental protection on sea and conservation of fishery resources has been rising up the major issue. All of the world are pushing their efforts two major purposes to the full, one is taking competitive place in marine transportation throughout the world and another Is environment protection. Pusan Port as world leading Port put its all effort in bring more ocean going vessels and securing their traffic route by providing them more information related marine traffics through PTMS in port. During two years of operation, statistics of marine traffic accidents showed that many dynamic casualties such as collisions, groundings, and rammings has been decreased. However, due to increasing cargo volume, limited water area and unpredictable weather condition, potential risks still exist high. In this paper, in order to maximize the efficiency of PTMS and reduce various risks in the future, we examine risk factors over operational results and experience, and propose reasonable operational methods of PTMS.

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5β-Hydroxypalisadin B isolated from red alga Laurencia snackeyi attenuates inflammatory response in lipopolysaccharide-stimulated RAW 264.7 macrophages

  • Wijesinghe, W.A.J.P.;Kang, Min-Cheol;Lee, Won-Woo;Lee, Hyi-Seung;Kamada, Takashi;Vairappan, Charles S.;Jeon, You-Jin
    • ALGAE
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    • v.29 no.4
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    • pp.333-341
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    • 2014
  • In this study, four compounds isolated from the red alga Laurencia snackeyi were evaluated for their potential anti-inflammatory effect in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. These compounds were tested for their inhibitory effects on nitric oxide (NO) production in LPS-stimulated RAW 264.7 cells. Since $5{\beta}$-hydroxypalisadin B showed the best activity it was further tested for the production of prostaglandin-$E_2$ ($PGE_2$), expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), the release of pro-inflammatory cytokines tumor necrotic factor-alpha (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$), and interleukin-6 (IL-6). $5{\beta}$-Hydroxypalisadin B significantly reduced the $PGE_2$ release and suppressed the iNOS and COX-2 expression in LPS-stimulated RAW 264.7 cells. It also significantly reduced the release of pro-inflammatory cytokines TNF-${\alpha}$, IL-$1{\beta}$, and IL-6. These findings provide the first evidence of anti-inflammatory potential of $5{\beta}$-hydroxypalisadin B isolated from the red alga L. snackeyi and hence, it could be exploited as an active ingredient in pharmaceutical, nutraceutical and functional food applications.

Outlier Detection of the Coastal Water Temperature Monitoring Data Using the Approximate and Detail Components (어림과 나머지 성분을 이용한 연안 수온자료의 이상자료 감지)

  • Cho, Hong-Yeon;Oh, Ji-Hee
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.2
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    • pp.156-162
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    • 2012
  • Outlier detection and treatment process is highly required as the first step for the statistical analysis of the monitoring data having many outliers frequently occurred in the coastal environmental monitoring projects. In this study, the outlier detection method using the approximate and detail (or residual) components of the (raw) data is suggested. The approximate and detail components of the data can be separated by the diverse filtering and smoothing methods. The decomposition of the data is carried out by the harmonic analysis and local regression curve, respectively. Then, the Grubbs' test and modified z-score method widely used to detect outliers in the data are applied to the detail components of the water temperature data. The new data set is reconstructed after removed the outliers detected by these methods. It can be shown that the suggested process is successfully applied to the outlier detection of the coastal water temperature monitoring data provided by the Real-time Information System for Aquaculture Environment, National Fisheries Research and Development Institute (NFRDI).

Development of a Lateral Flow Strip-Based Recombinase Polymerase Amplification Assay for the Detection of Haemonchus contortus in Goat Feces

  • Wu, Yao-Dong;Wang, Qi-Qi;Wang, Meng;Elsheikha, Hany M.;Yang, Xin;Hu, Min;Zhu, Xing-Quan;Xu, Min-Jun
    • Parasites, Hosts and Diseases
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    • v.59 no.2
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    • pp.167-171
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    • 2021
  • Haemonchosis remains a significant problem in small ruminants. In this study, the assay of recombinase polymerase amplification (RPA) combined with the lateral flow strip (LFS-RPA) was established for the rapid detection of Haemonchus contortus in goat feces. The assay used primers and a probe targeting a specific sequence in the ITS-2 gene. We compared the performance of the LFS-RPA assay to a PCR assay. The LFS-RPA had a detection limit of 10 fg DNA, which was 10 times less compared to the lowest detection limit obtained by PCR. Out of 24 goat fecal samples, LFS-RPA assay detected H. contortus DNA with 95.8% sensitivity, compared to PCR, 79.1% sensitivity. LFS-RPA assay did not detect DNA from other related helminth species and demonstrated an adequate tolerance to inhibitors present in the goat feces. Taken together, our results suggest that LFS-RPA assay had a high diagnostic accuracy for the rapid detection of H. contortus and merits further evaluation.

Analysis of the Rate of Post-Hatching Growth of the First Artificially Bred Green Turtle Chelonia mydas Juveniles in Korea (국내최초 푸른바다거북(Chelonia mydas)의 실내 인공 번식 및 어린 개체의 초기 성장 특성)

  • Cho, Eunvit;Kim, Il-Hun;Han, Dong Jin;Im, Jien;Cho, In Young;Lee, Ki-Young;Moon, Dae Yeon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.55 no.6
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    • pp.917-926
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    • 2022
  • The green turtle Chelonia mydas has been designated as an endangered species globally due to its reduced population. Although C. mydas is not known to reproduce on the shores of the Korean peninsula, it has been listed as a protected marine species in South Korea. This study describes the first successful captive breeding of C. mydas in a commercial aquarium in South Korea and provides information on the early growth patterns of C. mydas hatched and reared in indoor facilities. C. mydas YS-B003 laid a total of 594 eggs in ten nesting events in the period December 2016-June 2017. Of these, 115 fertilized eggs from six events hatched successfully. The size of the newly hatched turtles differed significantly among nesting events. The hatchlings from the 8th and 9th nesting events were relatively smaller than those from the 3rd and 5th events. The rate of growth initially varied across the different events, but from the 1,000th day, the inter-group variation disappeared. The present study provides useful information for future captive breeding of sea turtles in indoor facilities, which would contribute to the protection of these endangered sea turtle species.

Unrecorded species of Korean invertebrates discovered through the project of 'Discovery of Korean Indigenous Species' III

  • Su-Jung Ji;Jongwoo Jung;Sa Heung Kim;Dong-Ha Ahn;Min-Seop Kim;Jeounghee Lee;Hee-Min Yang;Geon Hyuk Lee;Eunjung Nam;Taeseo Park;Anna B. Jost;Huyen T. M. Pham;Jina Park;Joohee Park;Seoyoung Keum;Ivana Karanovic;Tomislav Karanovic;Joong-Ki Park;Chuleui Jung;Gi-Sik Min
    • Journal of Species Research
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    • v.12 no.4
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    • pp.341-354
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    • 2023
  • This is the third series of catalogs reporting on Korean species discovered through the 'Discovery of Korean Indigenous Species'. This catalog includes 22 species of invertebrates, excluding insects. The catalog includes the scientific name, an abridged list of synonyms, collection sites, distribution, diagnosis, and figures for each species. Additionally, we provide the newly assigned Korean name, specimen voucher, and, if available, mitochondrial CO1 or 16S gene sequences of the species listed. All species identified and documented here will be officially listed on the 'National Species List of Korea', a database maintained by the National Institute of Biological Resources(NIBR).

A Comparison in Characteristics of Chemical Composition of Glass Vessels Excavated from Neungsalli Temple in Buyeo, Korea, from Baekje Period

  • Koh, Min Jeong;Kang, Hyung Tae;Kim, Na Young;Kim, Gyu Ho
    • Bulletin of the Korean Chemical Society
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    • v.33 no.12
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    • pp.4173-4179
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    • 2012
  • From Neungsalli Temple located in Buyeo, ancient glass vessel fragments were discovered along with hundreds of glass beads. In this research, we used SEM-EDS to analyze glass vessel fragments and beads excavated from Neungsalli Temple. Then, we analyzed their chemical composition and examined their characteristics. In particular, we investigated a relationship between glass vessels from Neungsalli temple and Hwangnamdaechong (South tomb). The result of our experiment showed that the glass artifacts from Neungsalli temple were all soda glass. To be specific, the vessel fragments were soda-lime glass and spherical beads were high-alumina soda glass. Then, we compared glass vessel fragments from Neungsalli temple to glass vessels excavated from Hwangnamdaechong. Glass vessels from both sites turned out to be soda lime glass. We classified them further based on raw material used for soda - natron and marine plant ash.

Sampling Procedure of Black-tailed Gull (Larus crassirostris)'s eggs in National Environmental Specimen Bank for Monitoring Long-term Marine Environmental Pollution (해양 환경오염 모니터링을 위한 국가환경시료은행 괭이갈매기(Larus crassirostris) 알 시료 채취 절차)

  • Lee, Jangho;Lee, Jongchun;Lee, Sang Hee;Kim, Myungjin;Lee, Eugene;Han, Areum
    • Journal of Environmental Impact Assessment
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    • v.22 no.6
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    • pp.745-751
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    • 2013
  • Environmental Specimen Banks (ESBs) have been established widely in the world since 1979 for monitoring long-term bio-accumulation of environmental pollutants. The ESBs perform the retrospective analysis of representative biological samples collected regularly and store them in cryogenic condition. In Korea, National Environmental Specimen Bank (NESB) was established in 2009. Since then, NESB had prepared the standard operating procedures (SOPs) for the seven kinds of specimens (Red Pine (Pinus densiflora), Common Carp (Cyprinus carpio), and etc.) for monitoring the effect of environmental pollution on the terrestrial ecosystem and river ecosystem. In 2012, NESB added Black-tailed Gull (Larus crassirostris)'s eggs to the list of the environmental specimen for monitoring marine environmental pollution. In this study, we sampled the eggs of the Black-tailed Gull on two islands (Baekryeongdo of the West Sea and Hongdo of the South Sea). Especially, we selected eggs which remained in the early stages of embryo development for certifying the consistent and stable monitoring for environmental pollutants in egg contents. However, it was not considered to classify an order of eggs per clutch in this study. It is known that the concentration variations of pollutants exist among eggs in one clutch. Therefore, it is needed to consider the positions of eggs in the laying sequences to meet the objective of bioaccumulation monitoring. We collected 30 eggs in each site but the amount may be insufficient to achieve storage target (over 2,000 g). Therefore, we need to consider an optimal sampling size.