• 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 for Marine Environment & Energy
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• v.15 no.3
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• pp.227-237
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• 2012

This paper analyzes the current status, characteristics, and problems of coastal reclamation in Korea and suggests effective management approaches. Reclamation is concentrated from the West Sea to the South Sea. In the 1980s and 1990s, most projects were intended for agricultural use, whereas in recent years reclamation for industrial and harbour sites(e.g., ship-building) have been increasing. The continuous onslaught of reclamation and development projects threatens the coastal environment, especially tidal flats and fishing areas, and fishery production has been reduced in some areas. The largest tidal flats have been used for dumping sites of dredged coastal sediments, urban development projects, and industrial complex composition. Thus, it is necessary to assess current policy using top-down approaches after establishing appropriate directions and standards for coastal management. Both short-term development profits and long-term conservation should be considered when attempting to balance development and conservation. In addition, improvements of marine environmental impact assessment and in the legal system are necessary.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.4
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• pp.419-428
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• 2020

The flow past a wall mounted square cylinder, a typical and basic shape of building, bridge or offshore structure, was simulated using URANS computation through adoption of three turbulence models, namely, the k-ε model, k-ω model, and the v²-f model. It is well known that this flow is naturally unstable due to the Karman vortex shedding and exhibits a complex flow structure in the wake region. The mean flow field including velocity profiles and the dominant frequency of flow oscillation that was from the simulations discussed earlier were compared with the experimental data observed by Wang et al. (2004; 2006). Based on these comparisons it was found that the v²-f model is most accurate for the URANS simulation; moreover, the k-ω model is also acceptable. However, the k-ε model was found to be unsuitable in this case. Therefore, v²-f model is proved to be an excellent choice for the analysis of flow with massive separation. Therefore, it is expected to be used in future by studies aiming to control the flow separation.

• Journal of Environmental Health Sciences
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• v.33 no.6
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• pp.506-512
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• 2007

This study was conducted to describe the exposure levels of welding fumes by the type of manufacturers, work process, welding type and the size of manufacturers, and to find out the trend of chronological changes of airborne welding fume levels. The subjects of this study were 509 manufacturers, consisting of 11 types of manufacturers, 3 work processes, 7 welding types, in Busan from January, 1997 to December, 2005. Airborne concentration of welding fume was determined by manual of National Institute for Occupational Safety and Health (NIOSH), and the data were analyzed by using SPSS 10.0 for Windows program. The mean concentration of airborne welding fume in all manufacturers was $1.29\;mg/m^3$ (Range: $0.01{\sim}3.00\;mg/m^3)$. The level of welding fume was the highest, as $1.96\;mg/m^3$, for manufactures of motor vehicles, trailers and semi-trailers, which was lower than $5.0\;mg/m^3$ of 8 hr-TWA in Korean permissible exposure limit for welding fume. There was a significant difference in the mean levels of welding fumes by work process, showing the highest in welding workshop ($1.39\;mg/m^3$), followed by pipeline welding workshop ($1.26\;mg/m^3$) and engineering workshop ($1.20\;mg/m^3$). Among welding types, the mean level of welding fume was the highest in the type of $CO_2$ & arc welding, as $1.46\;mg/m^3$, followed by $CO_2$ welding ($1.40\;mg/m^3$), shielded metal arc welding ($1.31\;mg/m^3$), spot welding ($1.27\;mg/m^3$), and so on. The highest mean level of welding fume was $1.58\;mg/m^3$ in work process of pipe line welding workshop for the manufacturers of basic iron and steel, and $2.27\;mg/m^3$ in the type of arc welding for the manufactures building ship and boats. By the size of manufacturers, the mean concentration of welding fume for manufactures in small scale with less than 50 workers was the highest as $1.45\;mg/m^3$ (Range: $0.07{\sim}3.00\;mg/m^3)$. The mean level of welding fume was the highest as $1.39\;mg/m^3$ both in 1997 and in 2005, showing a trend of fluctuating periodically within a range of $1.10{\sim}1.39\;mg/m^3$. The above results suggested that more effective control program for work environment producing welding fumes should be developed and applied since there were significant variations in welding fume levels by the type of manufacturers, work processes, welding types, the size of manufactures, and by year.

• Journal of Korea Port Economic Association
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• v.33 no.1
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• pp.11-30
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• 2017

In addition to recession, world shipping companies are undergoing restructuring due to excess of "World Container Cargo volume" per "World Containership capacity" (in TEU terms). This excess is attributed to the absence of standard index of calculating the "World Containership capacity" (in TEU terms) for "World Container Cargo volume." The purpose of this study is to develop indices and terms: "World Containership capacity (in TEU terms) Standards Index; WCSI" and "World Containership capacity (in TEU terms) Expected Index; WCEI." The comparison between "WCSI" and "WCEI" made in this study is presented below. WCSI (Average voyage 9.3) > WCEI Excess shipping (in TEU terms) WCSI (Average voyage 9.3) = WCEI Optimum shipping (in TEU terms) WCSI (Average voyage 9.3) < WCEI Short shipping (in TEU terms) WCSI=HRCI $1000{\pm}150$ Value approx. The study shows that it is possible to predict "optimal supply of the world's containership capacity" (in TEU terms), "excess or shortage of shipping" (in TEU terms), "order time of container-ship capacity building" (in TEU terms), "order quantity of containership capacity" (in TEU terms), and "stable of World Shipping Companies" by "WCSI" and "WCEI." The development of "WCSI" and "WCEI" aim to help overcome the crisis of recession by establishing effective business strategies for world shipping companies and their supporting companies.

• Journal of the Korean Institute of Intelligent Systems
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• v.24 no.3
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• pp.337-342
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• 2014

This paper is aims to build the advancement structural model of GICOMS through identification of required system and improvement for implementation of e-Navigation. We derived nine improvement subject for model of advanced GICOMS through the analysis of problems for GICOMS and brainstorming with expert in the maritime safety. And we analyzed the structure of nine improvement subject using by FSM(Fuzzy Structural Modeling) method, and proposed a structural model that to grasp the correlation between elements. As a result, we found out that "advancement of GICOMS" is the final goal, and "improvement a system of information production", "improvement a scheme of information providing", "linkage between GICOMS and VTS" and "building global networks for safety cooperation" are located lowest level. Especially, "advancement of GICOMS" is influenced by "advancement function of VMS" and "Activation of usage" on middle level. We suggested that utilizing state-of-the-art IT facilities, equipment and expertise to improve and enhance the user-centered transition such as maritime workers for advancement of GICOMS based on proposed structure model.

• Korean Journal of Remote Sensing
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• v.34 no.2_2
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• pp.307-311
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• 2018

It is necessary to establish wide integrated surveillance system of marine territory to reduce damage caused by maritime security threats, marine pollution and accidents for safe and clean marine use and efficient development of marine resources. For marine surveillance, the information characteristics of space-time specific, accuracy and operability are required, and real-time information about the wide area should be provided at all times. This special issue has been published to identify the characteristics of each platform, evaluate its usability for the establishment of a wide integrated surveillance system, and present the direction for future convergence studies between platforms. Since 2015, KIOST and cooperative research team have been performing the project, "Base research for building wide integrated surveillance system of marine territory using multi-platform" that detect vessels and red tide etc. near real time by using satellite, UAV and HF Ocean Radar. The objective of this special issue is to introduce the significance for an integrated system for maritime surveillance and to create a forum for discussion on recent advances in remote sensing technology and applications for marine disasters, pollution, and accident surveillance.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.10a
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• pp.37-38
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• 2012

This study intended for Yokohama Minato Mirai21 district in Japan as waterfront, and Korea did an object again in Haeundae on high ground beach, a Jagalchi market. I carried out questionary survey in an object with the three places and investigated human waterside space consciousness to keep that I came and went. I analyzed the waterside space consciousness of the user to see a questionnaire result. It was 78.7% of 237 people, and there was much 'which felt the' sea breeze for the waterside space consciousness most, and 'that' which the 'sea was seen next saw 217 72.1%,' ship appeared by 203 67.4% order. I carried out reclassification for human five senses (sight, hearing, the sense of touch, taste, sense of smell) and activity, seven items such as the existence of the institution by the question contents of 19 about the waterside space consciousness each and grasped the consciousness of the waterfront user. As a result, Haeundae sense of smell was 32.3%, and a Jagalchi market was that sense of smell (26.1%) had an influence on the waterside space consciousness in 32.3% of taste, 21, Minato Mirai, Yokohama district, and sea building on high ground beach appeared.

• International Journal of Ocean System Engineering
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• v.2 no.3
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• pp.185-194
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• 2012

A Macroscopic combination of two or more distinct materials is commonly referred to as a "Composite Material", having been designed mechanically and chemically superior in function and characteristic than its individual constituent materials. Composite materials are used not only for aerospace and military, but also heavily used in boat/ship building and general composite industries which we are seeing increasingly more. Regardless of the various applications for composite materials, the industry is still limited and requires better fabrication technology and methodology in order to expand and grow. An example of this is that the majority of fabrication facilities nearby still use an antiquated wet lay-up process where fabrication still requires manual hand labor in a 3D environment impeding productivity of composite product design advancement. As an expert in the advanced composites field, I have developed fabrication skills with the use of machinery based on my past composite experience. In autumn 2011, the Korea government confirmed to fund my project. It is the development of a composite sanding machine. I began development of this semi-robotic prototype beginning in 2009. It has possibilities of replacing or augmenting the exhaustive and difficult jobs performed by human hands, such as sanding, grinding, blasting, and polishing in most often, very awkward conditions, and is also will boost productivity, improve surface quality, cut abrasive costs, eliminate vibration injuries, and protect workers from exposure to dust and airborne contamination. Ease of control and operation of the equipment in or outside of the sanding room is a key benefit to end-users. It will prove to be much more economical than normal robotics and minimize errors that commonly occur in factories. The key components and their technologies are a 360 degree rotational shoulder and a wrist that is controlled under PLC controller and joystick manual mode. Development on both of the key modules is complete and are now operational. The Korean government fund boosted my development and I expect to complete full scale development no later than 3rd quarter 2012. Even with the advantages of composite materials, there is still the need to repair or to maintain composite products with a higher level of technology. I have learned many composite repair skills on composite airframe since many composite fabrication skills including repair, requires training for non aerospace applications. The wind energy market is now requiring much larger blades in order to generate more electrical energy for wind farms. One single blade is commonly 50 meters or longer now. When a wind blade becomes damaged from external forces, on-site repair is required on the columns even under strong wind and freezing temperature conditions. In order to correctly obtain polymerization, the repair must be performed on the damaged area within a very limited time. The use of pre-impregnated glass fabric and heating silicone pad and a hot bonder acting precise heating control are surely required.

• Journal of Technology Innovation
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• v.23 no.3
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• pp.397-432
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• 2015

This paper investigates the effects of technology collaboration between the main supplier and buyer on buyer's new product development under dynamic environment. Based on 428 Korean manufacturing firms, we conducted regression analysis. The technology collaboration between the main supplier and buyer is adopted as a independent variable and quality, cost and lead time performance of new product development projects are used as dependents variables. Environment dynamic is also used as a moderate variables. We found that the in general, technology collaboration is positively associated with the performance of buyers' new product development, but in the high degree of dynamic environment, technology collaboration is negatively associated with the performance of buyers' new product development unlike our expectation. Thus, we divide our sample into two groups; shipbuilding industry with the low degree of environment dynamic and electronic and IT device industry with the high degree of environment dynamic and conducted a post hoc analysis. As a result, in ship building industry, the technology collaboration is significant to improve NPD projects performance, while in electronic and IT device industry, the technology collaboration with a main supplier is not significant as well as coefficient is negative. In that, under the highly dynamic condition with the fast change of technology and products obsolescence the NPD collaboration with the main supplier does not works unlike a stable environment. This implies that the NPD attributes of buyer are different by their environmental factor and the fit between given environmental feature and the collaboration synergy is critical factor for improving the effect of NPD collaboration between supplier and buyer.