• Ocean and Polar Research
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• 제39권4호
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• pp.301-318
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• 2017

The production of Korean offshore fisheries has been gradually decreasing due to the severe depletion of offshore fisheries resources caused by excessive fishing efforts. The production of the offshore fisheries in 2016 was the lowest since 1975. So the federal and local governments in Korea adopted and implemented various fisheries management plans and policies in order to restore fisheries resources. However, these plans and polices have not been successful in re-establishing fisheries resources. Thus, in order to accurately diagnose the situation with regard to offshore fisheries, this study sought to estimate not only the return to scale by fishing gear of offshore fisheries, but marginal productivity of individual fishing gear based on production factors derived from offshore fisheries production functions. The study was organized in the following manner. First of all, this study estimates production functions of offshore fisheries. The Cobb-Douglas and the translog production functions are adopted as offshore fisheries production functions. Specifically, the functions are estimated by crew, vessels, and offshore resource as production factors. The offshore resource is estimated by the Clarke Yoshimoto Pooley model based on the surplus production model. Secondly, the fisheries production functions are extended to the fixed-effect model and the random-effect model with panel data. Thirdly, this study analyzes the return to scale of offshore fisheries and the marginal productivity of the production factors from the estimated offshore fisheries production function. In conclusion, this study suggests plans and countermeasures for productivity improvement by group (labor intensive or technology intensive) based on the characteristics of individual offshore fishing gear.

• Ocean Systems Engineering
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• 제2권1호
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• pp.49-68
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• 2012

In this paper, an offshore process front end engineering design (FEED) method is systematically introduced and reviewed to enable efficient offshore oil and gas production plant engineering. An integrated process engineering environment is also presented for the topside systems of a liquefied natural gas floating production, storage, and offloading (LNG FPSO) unit, based on the concepts and procedures for the process FEED of general offshore production plants. Various activities of the general process FEED scheme are first summarized, and then the offshore process FEED method, which is applicable to all types of offshore oil and gas production plants, is presented. The integrated process engineering environment is presented according to the aforementioned FEED method. Finally, the offshore process FEED method is applied to the topside systems of an LNG FPSO in order to verify the validity and applicability of the FEED method.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2014년도 추계학술대회
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• pp.53-55
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• 2014

Offshore 에서의 oil & gas 생산은 해상이라는 환경으로 인한 고유의 특성 때문에 항상 다수의 변수들에 영향을 받으며, 막대한 비용이 소요되기 때문에 비용을 최소화하며, 비용 대비 수익을 최대화시키기 위한 optimal design이 필수이다. 본 논문은 가상의 offshore plant와 이에서 생산된 oil의 수요지들을 설정하여 시장수요에 따른 offshore 생산의 최적화 문제를 연구대상으로 하며, 다수의 offshore oil fields를 보유한 major oil company가 당면할 수 있는 offshore production에 관한 문제를 일반화하여 정의하고, 이윤을 극대화시킬 수 있는 최적화 모형을 혼합정수계획모형(mixed integer programming)으로 정식화 하였다. 최적화 모형의 해는 Microsoft office excel solver를 통해 구하였으며 그 계산실험의 결과를 요약하여 보고한다.

• 수산경영론집
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• 제43권3호
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• pp.23-30
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• 2012

This study aimed to analyze the economic feasibility of Mackerel offshore aquaculture production performance in Jeju region, Korea. Based on the collected biological, costs and market price data, farming revenue and expenses during the farming period were evaluated, and the net present value and the internal rate of return of a 10-year cash inflow and cash outflow were estimated to determine the economic feasibility of Mackerel offshore aquaculture production system. Model results indicated that the Mackerel offshore aquaculture production performance would have high profitability under the current production and market situation. This is because of the relatively high survival rate, relatively low feed conversion ratio and good market prices. However, sensitivity analyses of main important biological and economic variables showed that the economic viability of Mackerel offshore aquaculture production system would be highly vulnerable to production and market condition changes.

• 한국의류학회지
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• 제34권4호
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• pp.703-714
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• 2010

This study assumes that Korea's offshore outsourcing is used for diverse purposes such as designing, the supply of raw and subsidiary materials, production, and manufacturing. The purpose for production exists in the beginning stages of development, because it would have grown in scope since the 1990s when offshore outsourcing began in earnest. In this study, in-depth interviews were conducted with 24 firms with an annual production capacity of more than 200,000 pieces among clothing brands for the domestic market, clothing exporters, and promotion agencies. The interviews took place from December 18, 2008 to January 30, 2009. The interviewees were limited to the officers who had the authority to select manufacturers and decide on production volumes. Responses from the in-depth interviews were recorded, transcribed, and analyzed. The study results are summarized as follows: First, Korean clothing companies were found to rely on offshore outsourcing (China, North Korea, Vietnam, and Indonesia). Second, offshore outsourcing focused on the purposes for production; however, even fabrics were often outsourced in the case of production in China. Third, the interviewed firms mentioned cost savings, production cost reduction, and labor cost reduction most frequently as the main reasons for offshore outsourcing. Fourth, customs duties were considered most important in offshore outsourcing. Finally, when deciding on foreign manufacturers for offshore outsourcing, the surveyed clothing companies were found to: select manufacturers after market research in their outsourced countries, maintain existing contracts, or consider design capabilities and price quotations of candidate manufacturers.

• 한국해양공학회지
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• 제33권3호
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• pp.205-213
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• 2019

Recently, because of the global recession of the offshore plant industry and low-cost orders, there has been increasing interest in strengthening the competitiveness of domestic companies for the design and production technologies of offshore plants. However, in the offshore plant design field, the Plant Design Management System (PDMS), which is a 3D CAD program for plant layout developed by AVEVA Marine, is already commonly used as offshore plant design software and widely used in large domestic shipyards and cooperative design companies. Under this background, we have been thinking about ways to design better with the existing software. In this study, we developed a parametric design program to maximize the efficiency and reduce the working time for offshore plant electrical outfit production design based on the Programmable Macro Language (PML) of PDMS. We also examined its performance. By applying the developed program to the offshore plant module selected as an application example, it was confirmed that a 50% improvement in the work efficiency of cable tray design could be obtained compared with the existing method, with work efficiency improvements of 80% or more in other field design work.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2002년도 추계학술대회 논문집
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• pp.119-123
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• 2002

Liquefied Natural Gas(LNG) continues to attract modern gas industries as well as domestic markets as their main energy source in the recent years. This is mainly because LNG is inherently cleaner and more energy efficiency than other fuels. Offshore LNG production plant is of interest to many oil producing companies all over the world. This article discuss about the production process encountered while developing such a production facility. Typical offshore oil and gas processing required for oil stabilization and other optional units that can be added to the facilities. The production process can broadly be divided into five major units namely, (i) Oil Stabilization unit, (ii) Gas Treatment unit, (iii) Methane Recovery unit, (iv) Distillation unit and (v) LNG Liquefaction unit. The process simulation was carried out for each unit with a given wellhead composition. The topside facilities of offshore LNG production plant will be very similar to the process adopted in offshore processing platform along with the typical onshore LNG production plant. However, the process design problems associated with FPSO motion to be taken care of while developing floating LNG production plant.

• 대한조선학회논문집
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• 제50권6호
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• pp.373-382
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• 2013

The weight of floating offshore plant, such as an FPSO(Floating, Production, Storage, and Off-loading unit) and an offshore wind turbine, is important for estimating the amount of production material and for determining the production method. Furthermore, the weight is a factor which affects in the building cost and production time of the floating offshore plant. Although the importance of the weight has long been recognized, the weight has been roughly estimated by using the existing design and production data, and designer's experience. To solve this problem, a simplified model for the weight estimation of the floating offshore plant using the statistical method was proposed in this study. To do this, various data for estimating the weight of the floating offshore plant were collected through the literature survey, and then the correlation analysis and the multiple regression analysis were performed to generate the simplified model for the weight estimation. Finally, to examine the applicability of the developed model, it was applied to examples of the weight estimation of an FPSO topsides and an offshore wind turbine. As a result, it was shown that the developed model can be applied the weight estimation process of the floating offshore plant at the early design stage.

• 한국항해항만학회지
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• 제39권4호
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• pp.353-360
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• 2015

해양 석유 생산은 '해양'이라는 특성에 기인하는 여러 가지 변수를 동반하면서 막대한 비용과 시간을 필요로 한다. 모든 관련된 프로세스는 인명, 환경 그리고 재산의 손실을 줄이기 위한 치밀한 일련의 계획에 의하여 통제된다. 이 논문은 해양 석유 생산 및 수송의 최적화 문제를 다룬다. 문제 영역의 범위를 정의하기 위해 해양 석유 생산 및 수송 네트워크를 제시하고 그 문제를 해결하기 위한 혼합정수계획모형을 구축하였다. 제안된 최적화 모형의 타당성을 확인하기 위해 가상의 해양 유전과 수요 시장을 바탕으로 MS Office Excel의 해찾기를 이용하여 계산실험들을 수행하였다. 해양 석유 생산 및 수송 네트워크 하위 흐름은 해양 유전에서 생산된 원유를 수요 시장으로 배분하는 해사수송문제가 된다. 이 해사수송문제를 해결하기 위해 집합 패킹 모형을 이용하여 구축된 MoDiSS(Model-based DSS in Ship Scheduling)를 사용하였다. 이러한 연구결과들은 실제적인 해양 석유 생산 및 수송 최적화 문제에 의미 있게 적용될 수 있으리라 사료된다.

• 한국항해항만학회지
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• 제43권6호
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• pp.462-468
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• 2019

해양석유 생산은 예기치 못한 유가 하락과 글로벌 석유물류의 변화로 인한 여러 가지 어려움에 직면하고 있다. 이 연구는 불확실성하의 해양석유생산 최적화를 위한 추계적 모형을 제시한다. 제시된 추계적 모형은 강인한 최적화 모형과 리코스 제한 최적화 모형을 사용하고 리코스 이익 변동의 척도로 하위부분평균을 사용한다. 제안된 모형을 바탕으로 불확실성 하의 원유의 가격과 수요에 관한 시나리오 기반의 자료를 사용하여 수행한 계산실험 및 결과를 검토하여 보고하였다. 이 연구는 불학실성 하에서 위험을 고려한 해양석유생산 문제에 대한 의사결정에 유의하게 적용될 수 있을 것이다.