• Journal of Advanced Marine Engineering and Technology
• /
• 제33권2호
• /
• pp.355-361
• /
• 2009

Onshore wind farms having several problems, difficult to secure a building site and incur the enmity of the people. Therefore, offshore wind farms are increasingly expected, because there are huge resource and large site in offshore. If huge wind turbines are constructed, the offshore wind power base is concerned about subsidence. In order to confirm the ground stability, estimation of subsidence is necessary. In this paper, the subsidence is predicted by continuity model when the gravity and the mono-pile base are constructed on soft ground. The FLAC 3D, three dimensional FDM program, was adopted to analysis subsidence. Input factors are yielded by geological information at the yeompo quay in ulsan and the results of laboratory experiments. It has been compared that the original ground with improved ground under the gravity base, and constructed mono-pile under the mono-pile base.

• Journal of Advanced Marine Engineering and Technology
• /
• 제25권3호
• /
• pp.595-604
• /
• 2001

As an improvement in the standard of living and economic growth, the demand for air conditioning equipment is increasing rapidly. Nowadays, air conditioning equipments are being used for industry, large building, house and car. There equipments were concentrated on improving heat efficiency of economic aspects while thy design heat exchanger for cooling and heating. These air conditioning equipments using heat exchanger cause a discomfort to user due to generating mist at the beginning of operating. Therefore, the user demand air of high class and quality. In this experimental study, to acquire elementary data for development of heat exchanger which be able to supply air of high quality, that is to say, possess a restraint effect of mist generation. We estimate an effect on cooling plate quality, supply air velocity, supply air temperature, cooled plate temperature and supply air relative humidity which have an influence on outlet air condition of heat exchanger.

• 수산해양교육연구
• /
• 제20권1호
• /
• pp.107-120
• /
• 2008

Building a competency of pre-service school teachers is one of the critical factors to decide right direction of k-12 computer & information education. In this context, we can realize of the importance of computer & information curriculum for pre-service school teachers. The purpose of this study is to explore the case of the CEL(Computer Educator License) program in Indiana University and to find the developmental direction of technology education for pre-service school teachers. To achieve the purpose of study, the methods and procedures involved the following steps: The literature reviews of technology education were performed. The analysis framework based on case study method was designed for collecting data. Data were composed of related documents, web resources, and interview resources. And collected data were analyzed. The finding and recommendation of this study were the importance of following factors: (a) technology integration in the curriculum for pre-service school teachers, (b) differentiated management with skill-based technology education, (c) leadership for using and diffusing technology in the school, and (d) connected curriculum with the national standard indicator.

• 동아시아경상학회지
• /
• 제3권4호
• /
• pp.21-28
• /
• 2015

With CJK FTA as a starting point, this paper mainly studied the role of the logistics legal system in promoting marine industrial cooperation, facilitating investment trade, establishing international transport logistics, building marine economy international cooperation demonstration zone and deepening the economic and financial cooperation between China, Japan and Korea, and explored the way to establish an integrated logistics system between China, Japan and Korea to match the e-commerce certification system, online payment system and logistics distribution, thereby gradually promoting economic development and logistics integration in Northeast Asia, improving logistics efficiency, reducing logistics costs and establishing a unified logistics industry standardization system. This will accelerate logistics industry integration in Northeast Asia, build a unified logistics management center in Northeast Asia, and promote a new model of integrated logistics cooperation in Northeast Asia. Therefore, it has a practical and reference significance. In short, the improvement for the logistics legal system in CJK FTA is not the responsibility of a country or several countries. It concerns the development and prosperity for the logistics industry in the three countries and is an inevitable choice to promote the vigorous development of CJK FTA and economic take-off of each country.

• 한국해양공학회지
• /
• 제23권5호
• /
• pp.9-14
• /
• 2009

The green water on deck has many harmful effects on the vessel in rough seas such as damages to hull structures, damages to cargos, increase of the downtime, decrease of the stability, and so on. Floating Production Storage and Offloading vessels (FPSOs) are operated in a specific location and are normally positioned to meet mostly head or bow waves in order to reduce the roll motions. But this makes FPSOs more vulnerable to green water around the bow region therefore the bow shape should be properly designed to mitigate the green water damage. In this paper, experimental results in regular head waves for three kinds of bow shapes are compared and some design considerations are proposed, with the building a database for computational fluid dynamics (CFD) validation in mind.

• 수산경영론집
• /
• 제43권2호
• /
• pp.51-66
• /
• 2012

The purpose of this study is to present a new business performance model suitable for marin repair business. For this propose we have used survey datas gathered on several input and output factors from Marine engin repair companies Yeong-Do Gu. Gathering these the survey results we estimated the efficiency of each company through DEA method. The results of the analysis can be summarized as follows ; First, the result of the analysis showed 7 out of 24 DMU are not efficient companies. On the other hand 17 of them are efficient as the efficient output analyzes showed. Second, by analysing the results we could see significant differences between group companies, Ltd with a private companies with share on average efficiency in utilization. Third, two of the private companies are more effective and 6others were selected revisit and interview on the analysis. As a result inefficient DMU compared to efficient DMU and showed that they invest more on manpower in the field of sales and professional managers and techicians. Also, lots of effort devoted in order to standardize production by building capacity and environment management to improve welfare of the workers.

• 한국마린엔지니어링학회:학술대회논문집
• /
• 한국마린엔지니어링학회 2002년도 춘계학술대회논문집
• /
• pp.129-134
• /
• 2002

This study is focused on the layout design with sizing for the main propulsion shafting with controllable pitch propeller system. For appropriate design and successful manufacturing of controllable pitch Propeller system, it is based on specifications to be required from the customer as well as the stresses calculation and analysis of main propulsion system for hollow shafting. And it must be performed according to the U.S military specifications MIL-STD-2189(SH) with drawing of NAVSHIPS 803-2145807, and also the stress analysis by applying safety factor. The results are as follows : 1. For the main propulsion system with controllable pitch propeller, it is designed the following items propeller diameter, hub diameter, dimensions of oil distribution or actuating unit based on shaft mounting type, diameters of propeller and intermediate shaft, dimension of split muff coupling, coupling flange thickness and of coupling bolt diameter. 2. As the results, we can get complete our own design ability for the main propulsion shafting with controllable pitch propeller system with critical data which are necessary to establish shafting arrangement from the ship building companies.

• 한국정보통신학회:학술대회논문집
• /
• 한국해양정보통신학회 2003년도 추계종합학술대회
• /
• pp.343-347
• /
• 2003

최근 우리나라는 선박용도별 해양사고 발생률 중 100톤 미만의 어선 및 소형선박이 차지하는 비중이 72%에 달하고 있다. 그 원인을 살펴보면, 경계, 침로선정, 선위확인등 항해일반원칙의 미준수가 상당부분 차지하고 있다. 따라서, 본 논문에서는 비교적 고령화되고 운항지식이 적은 소형선박의 항해사에게 안전한 최적항로를 안내해주는 지능형 항해가이딩시스템을 구축한다. 지능형 항해가이딩시스템은 항로계획 프로그램과 항로전송부, GPS Plotter로 구성되어있다. 지능형 항해가이딩시스템을 통해 임의의 위치에서 목표지점까지 최적항로를 언어적으로 안내해주는 유효한 결과를 확인하였다.

• Journal of Advanced Marine Engineering and Technology
• /
• 제39권10호
• /
• pp.1062-1067
• /
• 2015

Floating architecture is a type of building that is geographically located on a sea or a river. It floats under the influence of buoyancy, and does not have an engine for moving it. Korea is a peninsula surrounded by sea except on the north side, so floating architectures have been mainly focused on two points: solving the issue of small territory and providing various leisure & cultural spaces. Floating architectures are expected to save energy effectively, if they use sea water heat, which is known to be clean energy with infinite reserves. To use sea water heat as the heat source and/or heat sink, this study proposes a model in which a sea water heat exchanger is embedded in the concrete structure in the lower part of the floating architecture that is submerged under the sea. Based on the results of performance evaluations of the sea water heat exchanger using CFD (computational fluid dynamics) analysis and mock-up experiments under various conditions, it is found out that the temperature difference between the inlet and outlet of the heat exchanger is in the range of $3.06{\sim}9.57^{\circ}C$, and that the quantity of heat transfer measured is in the range of 3,812~7,180 W. The CFD evaluation results shows a difference of 5% with respect to the results of mock-up experiment.

• 한국표면공학회지
• /
• 제41권4호
• /
• pp.156-162
• /
• 2008

Small FRP(fiber-reinforced polymer) fishing ships have numerous problems with the point of the environmental and recycling perspectives. In light of these aspects, aluminum can be used as a material for ship building. It is environmental friendly, easy to recycle, and provides a high added value to fishing boats. In this paper, we report on mechanical and electrochemical characteristics of welding parts for friction stir welded 5456-H116 Al alloy. In friction stir welded at various traveling speeds under the rotation speed of 500 RPM, the best characteristics presented in traveling speed of 15mm/min. The anodic polarizations of base metal and welding metal were observed tendency which current density from the open circuit potential suddenly increase. The cathodic polarization presented concentrated polarization caused by the dissolved oxygen reduction reaction and activation polarization caused by hydrogen generation. From result of Tafel analysis, the corrosion potential of 5456 alloy(Base metal) was lower than that of friction stir welded part, as were its corrosion current densities.