• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.3
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• pp.202-210
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• 2013

As incomes increase, interest in ocean leisure picks up. As a result, a lot of research and developments on hull form design and production of planing boats, mostly used for ocean leisure, are needed. Analysis in researches on resistance of planing boats shows that resistance characteristic of planing boats is different from resistance characteristic of general boats because the former is fast, and its wetted surface is very small. Using Savitsky formula widely used in the calculation of effective horse power in shipbuildingyards, and propulsion system and engine manufacturers, this study calculated total resistance of a research planing boat. Then it analyzed the flow characteristics of the planing boat through theoretical analysis and wind tunnel experiment, and computed air resistance and lift force by changes of speed and trim angle. It also compared and analyzed result of theoretical analysis and experiment of the ratio of air resistance to total resistance under variations of velocity and trim angle. When the study is used to estimate more accurate effective horse power, it is expected to remedy abuses of unnecessarily installing high-powered engine. As nature disasters due to abnormal changes of weather increase, interest in greenhouse gas grows. International Maritime Organization (IMO) legislated Energy Efficiency Design Index (EEDI) and Energy Efficiency Operational Indicator (EEOI) to reduce ship greenhouse gas emissions. But this index will be applied to over 400 tons ships, small ships, emitting more greenhouse gases than larege ships per unit power, will dodge the regulations. Thus, this study indicated a problem by calculating greenhouse gas emissions of an ocean leisure planning boat (a small ship), and suggested the need for EEDI of small ships.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.3
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• pp.275-285
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• 2010

Present state of nationwide marine facilities reported to 12 regional maritime affairs and port offices of MLTM in Korea for two years 2008 and 2009 was analyzed based on region and type of facilities, and national management plan was proposed in this study. As of the end of 2009, 8 types of marine facilities were reported to Yeosu regional maritime affairs and port office, while only 3 types of facilities were reported to Pohang, Daesan and Jeju regional offices, respectively. Oil and noxious liquid substances storage facilities belonged in the type of facility which was reported to all of 12 regional offices, and ranged from 11 facilities reported to Pyeongtaek regional office to the respective 38 facilities to Yeosu and Masan regional offices. In pollutants storage facilities, 4 facilities were reported to Masan regional office, 2 facilities to Donghae and Mokpo regional offices, respectively, 1 facility to Yeosu, Gunsan and Pyeongtaek regional offices, respectively, and none of facilities to the other regional offices. Ship construction, repair and scrap facilities belonged in the type of facility which was reported to all of 12 regional offices, and 45% of the facilities were concentrated in Southeastern Sea of Korea centering around Busan and Masan. In cargo handling facilities, 3 facilities were reported to Busan and Masan regional offices, respectively, 1 facility to Daesan regional office, and none of facilities to the other regional offices. In wastes storage facilities, 5 facilities were reported to Ulsan regional office, 4 facilities to Gunsan regional office, 2 facilities to Incheon regional office, 1 facility to Yeosu regional office, and none of facilities to the other regional offices. 65% of nationwide water intake and drainage facilities were concentrated in the areas of Pohang and Mokpo, and 78% of nationwide fishing spots at play were concentrated in the area of Masan. In other marine facilities, 4 facilities were reported to Donghae regional office, 3 facilities to Masan regional office, 2 facilities to Yeosu and Pyeongtaek regional offices, respectively, 1 facility to Incheon and Ulsan regional offices, respectively, and none of facilities to the other regional offices. In integrated marine science base facilities, 3 facilities were reported to Jeju regional office, 1 facility to Yeosu, Ulsan and Gunsan regional offices, respectively, and none of facilities to the other regional offices. The management based on the circumstances of regional offices, the management based on the characteristics of the type of facilities, the amendment of the relevant rules and regulations, facility owner's full knowledge and observance of the relevant rules and regulations with regard to the relevant type of facilities, and positive management actions from national point of view were proposed for national management plans of marine facilities.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.410-416
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• 2016

After the Sewol Ferry accident, the importance of maritime safety has been emphasized in Korea. In particular, educational and experience training are not only being conducted for maritime personnel but also in schools and at maritime-related organizations in order to broadly instill maritime safety awareness. Based on SOLAS regulations, safety education for sailors conducted every 10 days passenger boats, and fire-fighting drills and abandon-ship training should be conducted once a month on merchant ships. After the Sewol Ferry accident, the maximum number of trainees was reduced from 40 to 20 in order to improve the effectiveness of these training sessions by requiring all trainees to participate in the actual training. The current training process consists of two steps: textbook-based theoretical training and actual practice. Current training environment provides limited capability from human and facility recourses which limit the numbers of trainee participated and system operation time. By introducing the simulation training, it will improve the trainee skill and performance prior to the on-site training and allow the more effective and rapid progress on actual practice. Therefore, it will be proposed the three-step training method in order to improve the effectiveness on fire-fighting drill in Maritime Safety Education on this study. This study suggests a three step training method that would increase the efficiency of maritime safety education. An image-training step to enhance individual task awareness and equipment usage via simulation techniques after theoretical training has been added. To implement this simulation, a virtual training session will be conducted before actual training, based on knowledge obtained from theoretical training, which is expected to increase the speed with which trainees can adapt during the practical training session. In addition, due to the characteristics of the simulation, repeated training is possible for reaction drills in emergency circumstances and other various scenarios that are difficult to replicate in actual training. The efficiency of training is expected to improve because trainees will have practiced before practical training takes place, which will decrease the time needed for practical training and increase the number of training sessions that can be executed, increasing the efficiency of training overall. This study considers development methods for fire-fighting drill simulations using virtual reality techniques.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2018.11a
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• pp.225-227
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• 2018

This research paper examines the history and present of 'temporary passengers' prescribed in Paragraph 9 of Article 5 of the Ships Safety Act Enforcement Regulations and suggests improvement plans referring to the examples of legislation of other countries. In 2015, Ministry of Ocean and Fisheries made authoritative interpretation that Paragraph 9 of Article 5 of the Ships Safety Act Enforcement Regulations, which prescribes special cargo drivers such as agricultural, marine or livestock vehicles as temporary passengers, is applied only to passenger ships and not to cargo ships such including Ro-Ro cargo ships. As the authoritative interpretation of the Ministry does not agree with not only the traditional interpretational methodology but also the interpretational methodology that are commonly used today, it lacks logical basis and looks unpersuasive. Paragraph 9 of Article 5 of the Ships Safety Act Enforcement Regulations can be applied not only on passenger ships but also on cargo ships. Also in case of Ro-Ro cargo ships, it is logically contradictory and against fairness not to acknowledge special cargo vehicle drivers as temporary passengers when there is no problem with safe navigation and safety of passengers on board even when the sailor, the sailor's family and the ship owner may be acknowledged as temporary passengers. To avoid unnecessary disputes and lawsuits, improvement plans using theory of legislation through statutory reform is more desirable. Therefore, the P aragraph should be amended to "Supercargo who deals with cargo that requires special care due to the characteristics of the cargo, such as transportation vehicles for agricultural products, marine products, livestock, explosives or flammable materials (drivers can serve as supercargos)" to reflect the distinct characteristics of cargo and ship navigation in Korea including the current distribution system, while setting an objective standard based on common sense of ordinary people and not on arbitrary interpretation.

• Journal of the Korean Institute of Navigation
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• v.4 no.2
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• pp.45-79
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• 1980

The aim of this paper is to analyze the mechanics of price formation in the tramp shipping. For the purpose of this study, the main characteristics of tramp freight rates and the market is examined, and a brief examination of the nature ofthe costs of operation is given which are essential for the understanding of the functioning of shipping firms as well as for the understanding of developments in the tramp freight market. The demand and supply relationships in the market is also analysed in detail. Tramp shipping is an industry that has a market which functions under conditions that are not dissimilar to the theoretical model of perfect competition. However, it does notmean that tramp shipping market is a perfectly competitive market. It is apparent that this realworld competitive system has its imperfections, which means that the market for tramp shipping is near to being a perfectly competitive market on an internaitonal scale and it is freight are therefore subjext to the laws of supply and demand. In theory, the minimum freight rate in the short term is that at which the lowest cost vessels will lay-up in preference to operating, and is equal to the variable costs minus lay-up costs; and this would imply that in all times except those of full employment for ships there is a tendency for newer low-cost, and, probably, faster vessels to be driving the older high-cost vessels in the breaker's yards. In this case, shipowners may be reluctant to lay-up their ships becasue of obligations to crews, or because they would lose credibility with shippers or financiers, or simply because of lost prestige. Mainly, however, the decision is made on strictly economic grounds. When, for example, the total operating costs minus the likely freight earnings are greater than the cost of taking the ship out of service, maintaining it, and recommissioning it, then a ship may be considered for laying-up; shipowners will, in other words, run the ships at freight earnings below operating costs by as much as the cost of laying them up. As described above, the freight rates fixed on the tramp shipping market are subject to the laws of supply and demand. In other words, the basic properties of supply and demand are of significance so far as price or rate fluctuations in the tramp freight market are concerned. In connection with the same of the demand for tramp shipping services, the following points should be brone in mind: (a) That the magnitude of demand for sea transport of dry cargoes in general and for tramp shipping services in particular is increasing in the long run. (b) That owning to external factors, the demand for tramp shipping services is capable of varying sharphy at a given going of time. (c) The demad for the industry's services tends to be price inelastic in the short run. On the other hand the demand for the services offered by the individual shipping firm tends as a rule to be infinitely price elastic. In the meantime, the properties of the supply of the tramp shipping facilities are that it cannot expand or contract in the short run. Also, that in the long run there is a time-lag between entrepreneurs' decision to expand their fleets and the actual time of delivery of the new vessels. Thus, supply is inelastic and not capable of responding to demand and price changes at a given period of time. In conclusion, it can be safely stated that short-run changes in freight rates are a direct result of variations in the magnitude of demand for tramp shipping facilities, whilest the average level of freight rates is brought down to relatively low levels over prolonged periods of time.

• Journal of Korean Classical Literature and Education
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• no.38
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• pp.201-238
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• 2018

As a way of enhancing the intercultural ability needed for diverse cultural eras, this study focuses on the "narration" of the Italian education scholar Maddalena De Carlo in order to determine the "diverse values" created by the "symbolic representation" based on the folktales narrated by immigrants living in Korea. Through this, it specifically presents educational elements and contents that can raise relative sensitivity. The authors of this paper have connected, empathized, and communicated with people of various cultures in order to go beyond Carlo's discussion. The paper discusses the expansion of cultural sensitivity as an element of education through narrative topics using the folktales of immigrant narrators in Korea. It also recognizes the limitations of a desire for a homogeneous union within an intercultural society and thus formulates educational contents for creating a relationship with heterogeneous ideas through the elimination of communication barriers through heterogeneity and a consideration of the surface and the back. This is systemized in six steps. Step 1: Listening to oral folktales of immigrants, Step 2: Finding heterogeneous motifs imprinted in the immigrants' memories, Step 3: Understanding the meaning of the opposing qualities symbolized by heterogeneous motifs, Step 4: Creating narrative topics containing the key motifs, Step 5: Generating the value of symbolic representation as a narrative topic, and Step 6: Expanding the value of life into a cultural symbol. In Chapter 3, this study focuses on educational contents using immigrants' folktales by applying these six steps. The class contents include the recognition of the limitations of desire for a homogeneous union within an intercultural society and the consideration of how to create a relationship with heterogeneous ideas through the elimination of communication barriers through heterogeneity and consideration of the surface and the back. This paper then compares the Indonesian folktale, The Inverted Ship Mountain and the Mom's Mountain, with the world-famous Oedipus myth, to determine what the symbolic representation of these heterogeneous motifs is. In Step 6, when the symbolic system is culturally extended, the incestuous desire that appears in the "inverted ship" is interpreted as a fixation that was created when the character sought to unite with homogenous idea. The Cambodian folktale, The Girl and the Tiger, is a story that is reminiscent of the Korean folktale, The Old Man with a Lump. Through the motif in "Tiger," this paper generates a narrative topic that will enhance the students' intercultural abilities by culturally expanding their skills in how to relate with a heterogeneous being that is usually represented as an animal. The Vietnamese folktale, The Coconut Bowl, similar to the Korean folktale, GureongDeongDeong SinSeonBi, is a story that draws a variety of considerations about the surface and theback, and it shows readers how to build a relationship with a heterogeneous idea and how to develop and grow with such a relationship. Thus, if a narrative topic is generated and readers are able to empathize using an opposing feature formed by the core motif of the folktale, it becomes possible, through immigrant folklore, to construct a possibility of a new life through the formation of a relationship with an unfamiliar and heterogeneous culture.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.1-2
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• 2011

Hybrid rockets have lately attracted attention as a strong candidate of small, low cost, safe and reliable launch vehicles. A significant topic is that the first commercially sponsored space ship, SpaceShipOne vehicle chose a hybrid rocket. The main factors for the choice were safety of operation, system cost, quick turnaround, and thrust termination. In Japan, five universities including Hokkaido University and three private companies organized "Hybrid Rocket Research Group" from 1998 to 2002. Their main purpose was to downsize the cost and scale of rocket experiments. In 2002, UNISEC (University Space Engineering Consortium) and HASTIC (Hokkaido Aerospace Science and Technology Incubation Center) took over the educational and R&D rocket activities respectively and the research group dissolved. In 2008, JAXA/ISAS and eleven universities formed "Hybrid Rocket Research Working Group" as a subcommittee of the Steering Committee for Space Engineering in ISAS. Their goal is to demonstrate technical feasibility of lowcost and high frequency launches of nano/micro satellites into sun-synchronous orbits. Hybrid rockets use a combination of solid and liquid propellants. Usually the fuel is in a solid phase. A serious problem of hybrid rockets is the low regression rate of the solid fuel. In single port hybrids the low regression rate below 1 mm/s causes large L/D exceeding a hundred and small fuel loading ratio falling below 0.3. Multi-port hybrids are a typical solution to solve this problem. However, this solution is not the mainstream in Japan. Another approach is to use high regression rate fuels. For example, a fuel regression rate of 4 mm/s decreases L/D to around 10 and increases the loading ratio to around 0.75. Liquefying fuels such as paraffins are strong candidates for high regression fuels and subject of active research in Japan too. Nakagawa et al. in Tokai University employed EVA (Ethylene Vinyl Acetate) to modify viscosity of paraffin based fuels and investigated the effect of viscosity on regression rates. Wada et al. in Akita University employed LTP (Low melting ThermoPlastic) as another candidate of liquefying fuels and demonstrated high regression rates comparable to paraffin fuels. Hori et al. in JAXA/ISAS employed glycidylazide-poly(ethylene glycol) (GAP-PEG) copolymers as high regression rate fuels and modified the combustion characteristics by changing the PEG mixing ratio. Regression rate improvement by changing internal ballistics is another stream of research. The author proposed a new fuel configuration named "CAMUI" in 1998. CAMUI comes from an abbreviation of "cascaded multistage impinging-jet" meaning the distinctive flow field. A CAMUI type fuel grain consists of several cylindrical fuel blocks with two ports in axial direction. The port alignment shifts 90 degrees with each other to make jets out of ports impinge on the upstream end face of the downstream fuel block, resulting in intense heat transfer to the fuel. Yuasa et al. in Tokyo Metropolitan University employed swirling injection method and improved regression rates more than three times higher. However, regression rate distribution along the axis is not uniform due to the decay of the swirl strength. Aso et al. in Kyushu University employed multi-swirl injection to solve this problem. Combinations of swirling injection and paraffin based fuel have been tried and some results show very high regression rates exceeding ten times of conventional one. High fuel regression rates by new fuel, new internal ballistics, or combination of them require faster fuel-oxidizer mixing to maintain combustion efficiency. Nakagawa et al. succeeded to improve combustion efficiency of a paraffin-based fuel from 77% to 96% by a baffle plate. Another effective approach some researchers are trying is to use an aft-chamber to increase residence time. Better understanding of the new flow fields is necessary to reveal basic mechanisms of regression enhancement. Yuasa et al. visualized the combustion field in a swirling injection type motor. Nakagawa et al. observed boundary layer combustion of wax-based fuels. To understand detailed flow structures in swirling flow type hybrids, Sawada et al. (Tohoku Univ.), Teramoto et al. (Univ. of Tokyo), Shimada et al. (ISAS), and Tsuboi et al. (Kyushu Inst. Tech.) are trying to simulate the flow field numerically. Main challenges are turbulent reaction, stiffness due to low Mach number flow, fuel regression model, and other non-steady phenomena. Oshima et al. in Hokkaido University simulated CAMUI type flow fields and discussed correspondence relation between regression distribution of a burning surface and the vortex structure over the surface.

• The Journal of the Acoustical Society of Korea
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• v.28 no.4
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• pp.343-355
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• 2009

In order to restore the identity of sound environment and expand the sound culture of a region, the purpose of this study are to excavate the resources of soundscape and find out the plans for the preservation and promotion of soundscape resources peculiar to the region. For this purpose, this research is conducted through an interview survey of residents and an observation survey using listening walk in Hongdo, one of the southwesten island of Korea. The results of survey confirm that there are so many sounds to hear around Hongdo island, those are, natural sounds such as the song of the birds, the roar of the waves, the whistling sounds, the shriek of the seagulls, and the pebbles sounds washed away by the waves, and artificial sounds such as the steam-whistle signals, the ship's broadcasts, the voice of tourists, the sounds of church bells, lighthouse sirens etc. The results suggest that it is necessary to consider several ways for restoration of an unique soundscape in Hongdo island, those are, improvement for efficient management of a ship's broadcasts in public areas, removal of a ferry in Hongdo swimming beach, management of Dangsanje (a religious service), preservation of a lighthouse siren and a foghorn, restoration and improvement of underground stream, management and control of public fish market, restoration of brooklet, management of cooperative system for a fish market, restoration of PoongO-Gut (a ritual for a large harvest) and a skate festival, management of a Hongdo sports meeting, sound quality modification of a boat whistle, restoration of orientalia such as a funeral bier, ecosystem preservation activity of the shore and ocean, and promotion of amenity for fascination and vitality in a rural community. Also, a sound map is drawn up for many tourists so as to realize the importance of sound environment and identity of soundscape and to gain their experience at first hand in Hongdo island.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.3
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• pp.269-274
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• 2010

Present state of nationwide marine facilities reported to Minister of Land, Transport and Maritime Affairs{MLTM} in Korea for two years 2008 and 2009 was analyzed, and management plan was proposed in this study. As of the end of 2009, total number of nationwide marine facilities was reported to be 672 and to be scattered along the coasts all over the nation. 124 marine facilities reported to Masan regional maritime affairs and port office occupied 18.5% of total nationwide number. 69 marine facilities reported to Mokpo regional office and 69 marine facilities reported to Pohang regional office occupied 10.3%, respectively. 181 marine facilities reported to Busan and Masan regional offices occupied 26.9%, meaning that about a quarter of total nationwide marine facilities concentrated in Southeastern Sea of Korea centering around Busan and Masan. 320 oil and noxious liquid substances storage facilities occupied 47.6% of total nationwide number. 11 pollutant storage facilities occupied 1.6%. 178 ship construction, repair and scrap facilities occupied 26.5%. 7 cargo handling facilities occupied 1.0%. 12 waste storage facilities occupied 1.8%. none of marine facilities for tourism, housing and restaurant were reported. 88 water intake and outlet facilities occupied 13.1%. 37 fishing spots at play occupied 5.5%. 13 other marine facilities occupied 1.9%. 6 integrated marine science base facilities occupied 0.9% of total nationwide number. The guidance and the public relation for national report system of marine facilities, the improvement of national report system and management plan, the advancement and complement of national report affairs-handling guides, and the voluntary participation in national report system and the performance of duties by the owners of marine facilities were proposed for better management plan of marine facilities.

• Journal of the Korean Society of Marine Environment & Safety
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• v.22 no.5
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• pp.483-489
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• 2016

The type approval test for USCG Phase II must be satisfied such that living natural biota occupy more than 75 % of whole biota in a test tank. Thus, we harvested a community of natural organisms using a net at Masan Bay (eutrophic) and Jangmok Bay (mesotrophic) during winter season to meet this guideline. Furthermore, cell viability was measured to determine the mortality rate. Based on the organism concentration volume (1 ton) at Masan and Jangmok Bay, abundance of ${\geq}10$ and $<50{\mu}m$ sized organisms was observed to be $4.7{\times}10^4cells\;mL^{-1}$and $0.8{\times}10^4cells\;mL^{-1}$, and their survival rates were 90.4 % and 88.0 %, respectively. In particular, chain-forming small diatoms such as Skeletonema costatum-like species were abundant at Jangmok Bay, while small flagellate ($<10{\mu}m$) and non chain-forming large dinoflagellates, such as Akashiwo sanguinea and Heterocapsa triquetra, were abundant at Masan Bay. Due to the size-difference of the dominant species, concentration efficiency was higher at Jangmok Bay than at Masan Bay. The mortality rate in samples treated by Ballast Water Treatment System (BWMS) (Day 0) was a little lower for samples from Jangmok Bay than from Masan Bay, with values of 90.4% and 93%, respectively. After 5 days, the mortality rates in control and treatment group were found to be 6.7% and >99%, respectively. Consequently, the phytoplankton concentration method alone did not easily satisfy the type approval standards of USCG Phase II ($>1.0{\times}10^3cells\;mL^{-1}$ in 500-ton tank) during winter season, and alternative options such as mass culture and/or harvesting system using natural phytoplankton communities may be helpful in meeting USCG Phase II biological criteria.