• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.7
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• pp.1563-1568
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• 2003

The introduction of invasive marine species of living things into new environments by ship's ballast water, attached to ships' hulls and via other vectors has been identified as one of the four greatest threats to the world's oceans by Global Environment Facility(GEF). Making use of the new technology of alpha-AL$_2$O$_3$ dielectric barrier layer, the strong electric-field gas discharge was introduced and obtained between micro-gap electrodes at high pressure (∼105㎩) of $O_2$ in air and $H_2O$ in seawater. The mixed air with $H_2O$ could be ionized and dissociated into large numbers of activated particles of OH, $O_2$＋, O(1D), HO$_2$ and so on, and then dissolved into the ballast water to form dissolved hydroxyl radical with the concentration of ∼20mg/L. Therefore, the invasive marine species was treated effectively through the hydroxyl radical dissolved pipeline of ballast water by strong electric -field discharge.

• Journal of the Korean Society of Mineral and Energy Resources Engineers
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• v.55 no.6
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• pp.624-634
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• 2018

Indonesia has become a net crude oil importer because of the reduction of a new oil field discovery, and Indonesia is attempting to raise investment funds through the Kerja Sama Operasi (KSO) contract to develop a small-scale field. However, the KSO has a high-risk and low-return contract system for investors, necessitating an economic evaluation to examine the feasibility of the project. This study performed economic evaluation on the development of an Indonesian small-scale field by applying the KSO contract conditions, and identified the major economic parameters through a sensitivity analysis. As a result, the oil price, CAPEX and OPEX were identified as influential factors for economic evaluation. The results also indicate that commercial production in small-scale fields is difficult. In the future, this study can be used as a reference resource for investment in oil and gas development projects in Indonesia.

• Journal of Animal Science and Technology
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• v.48 no.5
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• pp.637-650
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• 2006

Genomic DNA isolated from two crucian carp species obtained from Yesan (Carassius auratus) and Dangjin (Carassius cuvieri) in Korea were amplified at several times by polymerase chain reaction (PCR). The amplified products were separated by agarose gel electrophoresis (AGE) with oligonucleotides decamer primer and stained with ethidium bromide. The seven arbitrarily selected primers OPC-11, OPC-14, OPC-18, OPD- 02, OPD-11, OPD-15 and OPD-20 generated the shared loci by each species, the polymorphic and specific loci. The seven primers generated the total 458 loci that can be scored from the crucian carp obtained in C. auratus species. 358 fragments were generated from the species obtained in C. cuvieri species. The size of DNA fragments varies from 150 to 1,600bp. The complexity of the banding patterns varies dramatically between the primers and two locations. In this study, 458 loci were identified in the crucian carp species from Yesan and 358 in the crucian carp species from Dangjin: 84 polymorphic loci (18.3%) in the C. auratus species and 48 (13.4%) in the C. cuvieri species. 154 shared loci by each species, the average 22 per primer, were observed in the C. auratus species and 187 loci, the average 26.7 per primer, in the Dangjin species. Based on the average bandsharing (BS) values of all samples, the similarity matrix ranged from 0.434 to 0.868 in the C. auratus species and from 0.449 to 0.924 in the C. cuvieri species. The average BS value was 0.641±0.013 within the C. auratus species and 0.684±0.013 within the C. cuvieri species. The average BS value between two crucian carp species 0.484 ± 0.007, ranged from 0.307 to 0.682. The BS value between the individual No. 09 and No. 16 was 0.682, which was the highest between two crucian carp species. Compared separately, the BS value of individuals within the C. cuvieri species was higher than the C. auratus species. The dendrogram obtained by the seven primers, indicates three genetic clusters: cluster 1 (AURATUS No. 01, 02, 03, 04, 05, 06, 07, 08, 09, 10 and 11), cluster 2 (CUVIERI No. 12, 13, 14, 15, 16, 17, 18, 19, 20 and 21) and cluster 3 (CUVIERI no. 22). The shortest genetic distance displaying significant molecular difference was between the individual AURATUS No. 09 and AURATUS No. 08 from Yesan (genetic distance=0.064). The longest genetic distance displaying significant molecular differences was between the individual CUVIERI No. 17 and AURATUS No. 11 between two crucian carp species (0.477). RAPD-PCR analysis has revealed the significant genetic distance between two crucian carp species pairs.(Key words: Carassius auratus, Carassius cuvieri, Crucian Carp, DNA Polymorphism, Genetic Distance)

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.4A
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• pp.565-571
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• 2008

Recently, the evaluation technique using NDT (Nondestructive Technique : NDT) is widely utilized because it makes little damage on RC (Reinforced Concrete : RC) structures. The techniques using electromagnetic properties (EM properties) are also attempted for the evaluation of the performance of concrete which is nonmetallic. For the economic manufacturing of concrete material, sea-sand is often used as aggregate, however, chloride ion in concrete has direct effects on steel corrosion and EM properties. In this study, OPC mortar specimens with 5 different chloride amount (0.0, 0.6, 1.2, 2.4, and $3.6kg/m^3$) and 3 different water-cement ratios (45%, 55%, and 65%) are prepared in order to investigate the EM properties corresponding to concrete properties. The EM properties of conductivity and dielectric constant are measured in the frequency range over 0.2~20 GHz. To facilitate the comparison of EM properties with chloride content, average values are taken respectively for the conductivity and dielectric constant measured over the 5~20 GHz frequency range. According to the results of this experiment, dielectric constant and conductivity are increased with lower W/C ratio and larger amount of chloride content.

• Journal of Environmental Science International
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• v.14 no.11
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• pp.1071-1079
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• 2005

Using single cell gel electrophoresis, DNA single strand breaks were determined in various marine organisms. DNA damage on fish blood cells was detected to know whether there was a difference between Incheon, Pohang, Masan, and Tongyeong as a control site. Tongyeong showed the lowest DNA damage among the study areas. Mussels, transplanted to Masan Bay for one month, revealed high DNA damage at sites with high economical activity. In two weeks exposure of polychaete to Incheon sediments, higher DNA damage was detected in the sediment adjacent to Incheon harbor than open sea. These results suggested that the marine organism from the polluted area revealed a relatively high DNA damage. In addition, these areas might be contaminated with genotoxic compounds and comet assay was useful as a bioassay to detect DNA damage in marine organisms.

• Korean Journal of Microbiology
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• v.33 no.1
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• pp.55-65
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• 1997

16S rRNA를 분석한 연구들은 자연 생태계에서 추출한 핵산을 이용하여 16rRNA 유전자의 염기서열을 분석하거나 특정 DNA probe를 이용한 hybridization 실험이 주류를 이루어 왔다. 특히 PCR 기법이 개발됨에 따라 적은 양의 시료를 대량으로 손쉽게 증폭시킬 수 있어 다양한 분야에 응용되고 있다. 세균 군집의 구조를 이해하는데 있어서 PCR 방법의 적용 대상은 주로 16S rRNA 유전자의 염기서열 해독분야이며 해양 생태계를 대상으로 많은 연구 결과가 보고되었다(11,13,21,26). 한편 자연 생태계의 개별적 미생물 분류룬들을 검출하기 위한 특정 oligonucleotide probe의 개발방법들은 미생물 군집의 유전적 다양성에 대한 정보 파악 이외에 배양이 어려운 혐기성 세균과 같은 특정 세균들의 동정에도 이용되고 있다(3,24,55). 본고에서는 세균 군집의 구조와 다양성을 연구하는데 적용 가능한 rRNA 분석방법들을 수계 생태계를 중심으로 살펴보고자 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2015.07a
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• pp.57-59
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• 2015

심해에서의 유전개발이 활성화되면서 이러한 개발에 필수적인 장비인 동적위치제어시스템 (Dynamic Positioning System, DPS)을 설치한 선박 또는 해양구조물의 수요도 폭발적으로 증가하고 있으며, 이에 따라 DPS 운영에 필수적인 DPO (Dynamic Positioning Operator) 자격증을 취득하고자 하는 지원자도 매년 급속하게 증가하고 있다. 그러나 DPO 교육훈련과정은 강제요건이 아니며, 따라서 엄정한 자격증명 및 검증이 어려운 실정이다. 특히 매년 2000건 이상의 신규면허를 심사하고 발급하는 것은 물론 기존 면허자에 대한 재검증 절차도 수행하여야 하는 현재의 상황으로 볼 때 효율적인 DPO 양성을 기대하기는 어려운 실정이다. 이 연구에서는 보다 이러한 문제점을 개선하여 보다 더 효율적이면서도 엄정한 DPO 양성을 위한 제도개선을 제안한다.

• Composites Research
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• v.17 no.4
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• pp.75-81
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• 2004

In applying phenolic composites in the marine market, Mech-Tool Engineering Ltd. U.K., for instance, they developed, based on their fire approval certificated technologies, many products such as bulkheads for boats, firewalls, blastwalls, blastrelief, escape route or tunnels, small modules, or safety havens and so on. These are one of very best applications with phenolic composites which may inspire you another fire protecting tools of your new products for our societies as well as those products.

• Korean Journal of Environmental Biology
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• v.20 no.1
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• pp.1-9
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• 2002

Copepods play an important role as a primary consumer in the various aquatic ecosystems. Most of marine benthic copepods belong to the Order Harpacticoida, and are known over 3,000 species in the world. Research on the biodiversity of the benthic copepods are important in the development of the new bio-resources, and the genetic resources. The importances and the prospects of biodiversity research on the mavins benthic copepods are discussed.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2001.05a
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• pp.152-157
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• 2001

This paper was studied on the characteristics of crevice corrosion prevention of SS 400 in marine environment. In NaCl solution, polarization behavior under the crevice corrosion was investigated. And Weight loss rate of SS 400 applied cathodic protection and non cathodic protection was measured according to the NaCl concentration. The main results obtained are as follows : The weight loss rate of Al-alloy galvanic anode was increased as the concentration of NaCl solution increased by 3.5% but the concentration increased over 3.5%, that of Al-alloy galvanic anode become decreased. The protective potential of SS 400 used Al-alloy galvanic anode becomes more cathodic polarization with increasing concentration of NaCl solution. Effects of oxygen on the weight loss rate of Al-alloy sacrificial anode for cathodic protection as the concentration of 3.5% NaCl solution become sensitive than that of 0% NaCl solution.