• Computational Structural Engineering
• /
• v.2 no.3
• /
• pp.11-13
• /
• 1989

현재 심해에서의 석유개발을 위하여 사용되는 구조물의 설계 및 해석에 관한 기술은 수심 약 600 m까지 어느 정도 확립되어 있고, 또한 극지환경하에서의 석유개발용 구조물에 관한 기술도 상당한 수준에 올라 있다고 판단된다. 그러나 아직도 많은 분야에 걸쳐 기술의 개발과 개선을 요구하고 있다. 아울러 이에 관계되는 많은 문제들은 구조공학적인 분야만이 아니라 기계, 재료, 전자, 조선, 해양공학 등 거의 모든 공학분야의 기술이 총체적으로 지원되어야만 해결이 가능하게 된다. 본 고에서는 심해 및 극지유전개발에 사용되고 있는 구조물을 소개하고 이들이 가지고 있는 기술적인 문제점에 대해서 살펴보고자 한다.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2001.05a
• /
• pp.87-92
• /
• 2001

This technical note is intended to introduce a state-of-the-art offshore construction vessel. This unique vessel is for multi-purpose Field Development Ship (FDS) for deepwater to ultra-deepwater. The FDS is a construction vessel with dynamic positioning (DP) system intended to develop offshore oil and gas field in water depth up to 3000 m. The design criteria and main capacities of the vessel are discussed.

• Proceedings of KOSOMES biannual meeting
• /
• 2017.04a
• /
• pp.82-82
• /
• 2017

Chum salmon, Oncorhynchus keta, has received considerable attention in recent years for population genetic studies due to its broad geographic distribution and high commercial importance in North Pacific fisheries. The Bering Sea and North Pacific Ocean provide major feeding habitats for various salmon stocks originating from Japan, Russia and North America. Chum salmon are a dominant pelagic fish in the Bering Sea during summer and their numbers fall when they moved in coastal areas to spawn. Population genetic data for chum salmon that can serve as a baseline for stock identification studies are scarce. In this review, we describe recently developed molecular markers and discuss their use in the study of genetic population structure of chum salmon in the Pacific Rim. In addition, we review previous genetic studies focused on the assessment of stock compositions in mixed chum salmon aggregations in the Bering Sea and North Pacific Ocean.

• Korean Journal of Microbiology
• /
• v.54 no.3
• /
• pp.305-307
• /
• 2018

The whole genome sequencing using PacBio RS II platform was performed for a marine bacterium Pseudoalteromonas donghaensis $HJ51^T$ isolated from East Sea of Korea. As a result, three assembled contigs consisting of a chromosome (size of 3,646,857 bp, and G + C content of 41.8%) and two plasmids (size of 842,855 bp and 244,204 bp, and G + C content of 41.3% and 40.4%, respectively) were obtained. The genome included 4,083 protein coding genes and 127 RNA genes. This result could be used for gene sources of biopolymers degradation and the development as a new host with secretion system similar to Escherichia coli.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2012.10a
• /
• pp.271-273
• /
• 2012

브라질은 최근 심해유전(Pre-Salt)개발 등 해양자원개발 등을 통해 신흥자원부국으로 각광받고 있다. 올 해 6월 국영석유기업인 페트로브라스가 '2012-2016 Business Plan'를 통해 향후 5년 간 E&P, 정제 및 운송 분야에 2,073억 달러를 투자한다고 밝히면서 향후 해양플랜트 및 OSV 수요가 커질 것으로 예상된다. 브라질이 우리나라 조선, 해운, 전문 인력 분야에서 협력대상으로 한국을 염두에 두고 있어 특히 OSV 건조 및 운영과 관련해 우리나라 기업의 진출 전략 수립이 필요하다. 이 글은 브라질 OSV 시장 현황 및 정부 정책, 그리고 우리나라 진출 전략을 크게 현지네트워크 강화를 통한 페트로브라스 공략, 로컬 콘텐츠 대응 전략 수립, OSV 운영에 특화된 전문인력 양성, 선사 조선소 기자재 업체 협력체계 구축, 정부 지원 확대 등으로 제시한다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.18 no.3
• /
• pp.131-141
• /
• 2013

Stock identification of Todarodes pacificus collected in the East Sea, Yellow Sea and East China Sea during the period from September to December in 2011 was analyzed by morphometric characters and mitochondrial DNA (mtDNA) cytochrome oxidase subunit I (COI) gene nucleotide variations. Frequency distributions of mantle length was analyzed by morphological method with measuring size of T. pacificus. Then each stock was estimated to confirm their maturation for mean mantle length comparing with mean mature mantle length 20-22 cm. According to morphologic stock identification, it is estimated that the northern part of East Sea is categorized as summer stock and the rest parts, including mid /southern part of the East Sea, northern part of the East China Sea and northern part of the West Sea were autumn stock. For genetic analysis, a total 49 haplotypes were defined by 33 variable nucleotide sites. From the extensive haplotype diversity, limited nucleotide diversity and star-like shape of haplotype network, T. pacificus appears to have undergone rapid population expansion from an ancestral population with a small effective population size. Although pair-wise Fst estimates which represent genetic difference among groups were low, there are relatively remarkable difference of Fst between middle and southern part of the East Sea. Although middle part of the East Sea and southern part of the East Sea were situated at the East Sea, genetically separated groups were appeared.

• Korean Journal of Ichthyology
• /
• v.33 no.4
• /
• pp.226-239
• /
• 2021

Sebastes minor, Sebastes trivittatus, Sebastes owstoni, and Sebastes steindachneri are indigenous fish species inhabiting the central part of the East Sea, Korea. In order to understand the molecular evolution of these four rockfishes, we sequenced the complete mitochondrial genomes (mitogenomes) of S. minor and S. trivittatus. To further analyze the phylogeny of Sebastes species, the mitogenomes of 16 rockfishes were comparatively investigated. The complete mitochondrial DNA (mtDNA) nucleotide sequences of S. minor and S. trivittatus were 16,408 bp and 16,409 bp in length, respectively. A total of 37 genes were found in mtDNA of S. minor and S. trivittatus, including 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, which exhibited similar characters with other Sebastes species in the East Sea, Korea. In addition, we detected a conserved motif "ATGTA" in the control region of the four Sebastes species, but no tandem repeat units. Comparative analyses of the congeneric mitochondrial genomes were performed, which showed that control regions were more variable than the concatenated protein-coding genes. As a result of analysing phylogenetic relationships of four Sebastes species by using concatenated nucleotide sequences of 13 protein-coding genes, S. minor, S. trivittatus, S. owstoni and S. steindachneri were clustered into three clades. The phylogenetic tree exhibited that S. minor and S. steindachneri shared a closer relationship, whereas S. trivittatus and S. vulpes formed another distinct clade. Our results contribute to a better understanding of evolutionary patterns of Sebastes species inhabiting the middle East Sea, Korea.

• Journal of Navigation and Port Research
• /
• v.43 no.6
• /
• pp.462-468
• /
• 2019

Offshore oil production faces several difficulties caused by oil price decline and unexpected changes in the global petroleum logistics. This paper suggests a stochastic model for optimizing the offshore oil production under uncertainty. The proposed model incorporates robust optimization and restricted recourse framework, and uses the lower partial mean as the measure of variability of the recourse profit. Some computational experiments and results based on the proposed model using scenario-based data on the crude oil price and demand under uncertainty are examined and presented. This study would be meaningful in decision-making for the offshore oil production problem considering risks under uncertainty.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.34 no.4
• /
• pp.205-212
• /
• 2021

Offshore jacket structures generally comprise steel members, and the safety standard for jacket structures typically focuses on the steel components. However, large amounts of concrete grouting is filled in the legs of the Gageocho jacket structure to aid in the recovery from typhoon damage. This paper proposes a safe and lightweight design for the Gageocho ocean research station comprising steel members instead of large amounts of concrete reinforcement in the legs. Based on the actual design, the structural members are grouped according to their functional roles, and the inner diameter of the cross-section in each design group is defined as a design variable. Structural optimization is carried out using a genetic algorithm to minimize the total weight of the structure. To satisfy the conservative safety standards in the offshore field, both the maximum stress and the unity check criteria are considered as design constraints during optimization. For enhanced safety confidence, extreme environmental conditions are assumed. The maximum marine attachment thickness and the section erosion in the splash zone are applied. Additionally, the design load is defined as the force induced by extreme waves, winds, and currents aligned in the same direction. All the loading directions surrounding the structure are considered to design the structure in a balanced and safe manner. As a result, compared with the current structure, the proposed structure features a 45% lighter design, satisfying the strict offshore safety criteria.