• Corrosion Science and Technology
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• v.10 no.4
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• pp.136-142
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• 2011

Al alloys have been used widely for commercial and military ships in most ocean countries since mid-1950s, and the value as light metal with high mechanical strength has been proven. As the safety and fuel efficiency of Al ships have improved, she can carry more freight, sail faster and travel longer distances. Furthermore, in the shipbuilding industry, Al alloys are applied as structural materials for ships to various areas including the deck of luxurious cruises, battleships and leisure ships. In addition, Al alloys are being spotlighted as environmental-friendly material as they can be recycled even after end of lifespan. However, Al alloys for ships must be carefully selected after considering corrosion resistance, endurance, strength, and weldability in sea water environment. Al alloys to satisfy these conditions are used widely include 5000 series Al-Mg alloy and 6000 series Al-Mg-Si alloy. Thus, this study selected and evaluated the cavitation characteristics of the 5000 series Al alloys that are used in hulls that directly contact seawater and the 6000 Al alloys that are used in the upper structures of ships. Results of cavitation test with time, weightloss and cavitation rate of 5456-H116 showed the smallest damage among 5052-O, 5456-H116 and 6061-T6.

• Journal of the Korean Society of Marine Environment & Safety
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• v.20 no.4
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• pp.426-434
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• 2014

The research developed twin keel yacht for everyone which is able to stand erectly on mud flat without list and intended to commercialize the development product for popularization of west coast's marine leisure industry. Yacht's linear was utilized by "Blue Water21" has superior performance among the existing sailing yachts and twin keel model has been tested by calculation of mono keel's extent and its center of gravity. The result was that only 4 % of difference have been identified between mono keel and twin keel's hydrodynamic resistance which was smaller difference than predicted.

• Journal of the Society of Naval Architects of Korea
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• v.48 no.6
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• pp.479-489
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• 2011

Leisure boat and yacht should be designed to meet the domestic regulation and international standards as large merchant vessels do. Recently, each countries are encouraged to follow the regulation of International standards organization. Furthermore domestic organization has not yet announced the design rule and regulation for FRP-catamaran yacht design. Therefore, it has been required to make the regulation for domestic situations of FRP-catamaran. This study deals with the structural strength evaluation of 50ft catamaran by using finite element analysis. Design load of the regulation of International standards organization are compared with the regulation of Korea Register of shipping and Lloyd's Register.

• Journal of the Society of Naval Architects of Korea
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• v.47 no.5
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• pp.703-708
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• 2010

Recently, the development of the Marina port is determined as a national plan, and a variety of leisure boats and facilities on the field has been of critical interest. In particular, yachts are designed and produced mostly at small shipbuilding companies and research institute. The regulation and historic data, however, about the safety of structure are not readily available. Therefore, it is required to evaluate the strength of ship structure. This paper deals with the estimation of local strength of 40 feet sailing yacht by using finite element analysis. The forebody, mast and connection parts of a FRP yacht structure are evaluated. In addition, the results are compared with the regulation of Lloyd's register and Korean register.

• Journal of the Korean Institute of Intelligent Systems
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• v.26 no.3
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• pp.239-245
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• 2016

In the midst of continuing international recession, the rate of maritime traffic and marine leisure markets are consistently growing. The Republic of Korea controls the marine traffic volume through vessel traffic centers and various other management facilities. Nevertheless, the continuous growth and complexity of marine traffic is resulting in repeated occurrences of marine accidents. Recovery is very difficult in cases of human injuries or deaths caused by marine accidents due to its nature, and the scale of marine accidents is also becoming greater with advanced ship building technologies. Passenger ships, oil tankers, and other such vessels used for specific purposes requires a more detailed navigational status surveillance and analysis, and numerous research has been conducted with an objective for monitoring such special purpose vessels. However, the data elements transmitted from the ocean to the shore station are limited to AIS and ARPA. We are implementing IoT ship sensor collection and a syncing system capable of transmitting various ship sensing data to the shore station, and also proposing a Safe Navigation Status Analysis System utilizing the collected data.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.1
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• pp.67-72
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• 2017

This study developed an electric power propulsion personal watercraft by combining a battery and an electric system from the domestic automobile industry with water motorcycle from marine leisure industry in a convergence of technology. It also developed a safety inspection plan and type approval standard for personal watercraft that use electric power propulsion. For the registration and production of the electric power PWC (Personal Watercraft), a safety inspection standard (draft) and type approval standard (draft) have been established. PWC that use this electric power propulsion certification standard have been divided into two categories according to the use of gasoline engines as related to the ship's electrical system. The contents of these safety inspections standards is divided into 7 categories, and their purpose is to confirm the facilities used for the safe operation of PWC. Type approval is divided into 7 categories and is intended to ensure the safe production of PWC. This is basic data can be used to establish criteria for safety inspection and type approval of electric power propulsion vessels and to guide the production of the environmentally friendly PWC in Korea.

• Composites Research
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• v.35 no.5
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• pp.347-358
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• 2022

Carbon fiber is an excellent structural material, which has been proven in many industries, and the shipbuilding industry is no exception. In particular, in advanced maritime countries, special ships of the Navy and Coast Guard with carbon fiber composite hulls have already been deployed. In Korea, carbon fiber composite materials have been applied to a 10-ton class leisure craft or a 30-ton class patrol, but no research has been done on a hundred of tons or more vessels. In this study, the feasibility study of a 500-ton patrol vessel with a carbon fiber composite hull was conducted through an analysis of similar cases abroad. As a result, it was recognized that the developed hull can be reduced in weight by about 21% to 25% compared to the existing aluminum or FRP hull. It was also confirmed that this light-weight effect can induce the improvement of the maximum speed and the improvement of the operating range via simulations.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.674-680
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• 2013

As the range of marine leisure activity gradually expands to ocean-going, a habitable cruise boat has been getting the limelight. Advanced countries in the marine leisure industry in Europe and North America have already secured their competitiveness in designing and building cruise boats by elegant design, ergonomic structure and fuel efficiency through the adoption of light-weight hull materials. In contrast, mostly small power boats are developed and built in Korea, and GFRP take up the most of hull materials. This study inquired into the design and characteristics of a 50ft-class CFRP that ocean-going is possible. The hull-form of the CFRP cruise boast were analyzed to propose a hull form for the designed ship (MMU-C.B), and based on that, the design model of the MMU-C.B was built. Finally, the MMU-C.B's characteristics of the resistance performance and hull-planing were found by comparative reviews with the results of model tests of GFRP pleasure yachts.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.4
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• pp.366-374
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• 2013

Maritime transportation circumstance is changing rapidly in accordance with the increase of cargo volume between countries and increase of marine leisure activities by improvement of quality of life. And the circumstance for ship operation is also changing due to aging of seafarers and increasing of foreign seafarers. To cope with such changes in maritime environment well, it requires higher safety management skills from shipping companies, the main subject in charge of the safety matter. In this paper, we analyzed domestic and foreign similar system, and then applied imitation strategies for introduction of an unific evaluation and management system that was consist of marine accidents, port state control, ISM Code and so on from shipping companies. We defined that the imitation industry and system are converted accident ration of construction industry and traffic safety excellence company of road transportation, and then extracted relevant law, evaluation index, incentive system as a imitation subject. We also proposed scheme that introduction of basis law, and evaluation tool with marine accidents ratio, port state control & ism code result, and incentives such as immunity of safety inspection or reduction of commission for introduction of company's safety management level evaluation system. Finally, we proposed the imitation timing and plan in stages for system's sustainable development through the prompt introduction and continuous enforcement.

• The Korean Journal of Rehabilitation Nursing
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• v.5 no.1
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• pp.71-85
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• 2002

The purpose of study was to find out the relation ship between health perception and health status of clinical nurses. It also identified factors that related to health perception and health status of clinical nurses. The research design was descriptive correlational study. The subjects were consisted of 289 clinical nurses at the university hospital in Pusan. The data were collected from Feb. 12th to Feb. 28th, 2001 by self reporting structured questionnaires. The instruments used for this study were health perception questionnaire developed by Ware and Cornell Medical Index modified by Nam Ho-Chang (1965) for measuring health status. The data were analyzed by SPSS/PC+ program using frequency, percentage, mean, mean mark, standard deviation, t-test, ANOVA, Scheffe test, and Pearson's correlation coefficient. The results of this study were as follows. 1. The mean score of the health perception was $94.70{\pm}8.93$(range : 29-145), which the item mean mark score was $3.27{\pm}$0.31(range 1-5). The score of subarea of the health perception was the highest score in health concern ($4.57{\pm}0.58$) and the lowest score in rejection of sick role($2.94{\pm}0.32$). 2. The mean score of the health status was $102.83{\pm}7.61$(range: 57-114), which the item mean mark score was $1.80{\pm}0.13$ (range : 1-2). The mean mark score of the physical health status was $62.55{\pm}5.35$($1.69{\pm}0.14$) and the mental health status was $40.28{\pm}3.51$($1.83{\pm}0.16$). 3. There were statistically significant difference in the score of health perception according to the presence of disease(F=4.607, P=.011), job satisfaction (F=12.242, P=.000), and job place(F=2.838, P=.038). 4. There were statistically significant difference in the score of health status according to the age(F=3.164, P=.007), presence of leisure time(F=4.308, P=.039), presence of diseases(F=3.215, P=.042), job experience(F=9.064, P=.000), job satisfaction(F=7.182, P=.001), job place (F=5.638, P=.001), job position (F=3.900, P=.021). 5. Health perception of clinical nurse was shown to be positively related to health status(r=.543, p=.000). In conclusion, health perception of clinical nurse working at the university hospital was relatively high, and health status was fine. And the more health perception was high, the more health status was high. Therefore, the health promotion program for clinical nurses, should included health perception.