• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.12 no.3
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• pp.178-185
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• 2007

Myrionecta rubra Jankowski 1976(=Mesodinium rubrum Lohmann 1908), a mixotrophic ciliate, is very common and often causes recurrent red tides in diverse marine environments. Since the report on the first laboratory strain of this species in 2000, papers on its novel ecological role and evolutionary importance have been high lighted. This review paper is prepared to promote the de novo recognition M. rubra as a marine mixotrophic species. M. rubra is a ciliate which is able to photosynthesize using plastids originated from cryptophyte (including Teleaulax sp. and Geminigera sp.) prey cells (i.e. kleptoplastidic ciliate). Recently, novel bacterivory of M. rubra was firstly reported. Thus, the nutritional modes of M. rubra include photosynthesis, bacterivory, and algivory. In turn, M. rubra was reported as the prey species of metazoan predators such as calanoid copepods, mysids, larvae of ctenophore and anchovy, and spats of bivalves. In addition, it was reported that dinoflagellate Dinophysis causing diarrhetic shellfish poisoning is one among the predators of M. rubra. Thus, M. rubra, a marine mixotrophic ciliate, may play a pivotal role as a common linking ciliate for the flow of energy and organic material in pelagic food webs.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.13 no.4
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• pp.308-319
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• 2008

Temporal variations in plankton assemblages and environmental factors in Asan Bay and their relationships were examined with the data collected from February till early June, 2005. Seawater temperatures showed typical pattern of temporal change observed in temperate waters. Salinity variation was minor. Phytoplankton biomass showed two peaks, one in February only in the inner part of the bay and the other in May in the whole bay. Phytoplankton succession was clearly shown with the increase of seawater temperatures. Diatom (Bacillariophyceae) dominated in February, diatom and cryptomonads (Cryptophyceae) prevailed in May, and dinoflagellates (Dinophyceae) was most abundant in June. Spring bloom in Asan Bay occurred about one month earlier than those observed in temperate seas. Among the inorganic nutrients (N, P and Si), only silicate concentration showed a significant negative correlation with phytoplankton biomass, indicating the sink of this nutrient in the bay to be the uptake by phytoplankton. Nitrate concentration seemed to be a limiting factor in this bay during the study period. Mesozooplankton abundances showed a significant positive correlation with seawater temperatures and a significant negative correlation with phytoplankton biomass. Increase of mesozooplankton abundance followed phytoplankton increase with the time lag of about two months. This increase of zooplankton seemed to be the result of increased seawater temperatures and food.

• Economic and Environmental Geology
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• v.57 no.1
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• pp.93-105
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• 2024

Chilgok Geummubong tree fern fossil site is the type locality where tree fern stem fossils (Cyathocaulis naktongensis) were first discovered by Tateiwa in 1925. Recognized for its academic value, it was designated as a natural monument in the 1930s during the Japanese colonial period, and preserved and managed for over 90 years. However, at the time of discovery, the stratigraphic level of tree fern fossils could not be located because the fossils were fragments detached from the rock body, and thus the Geummubong area where the conglomerate/sandstone layers of the Nakdong Formation are distributed, has been designated as a cultural heritage area. Only in the 2000s, when tree fern fossils were directly recovered from the outcrops near the designated area, the sedimentary rock facies containing the fossils were interpreted, and the anatomical characteristics of the Mesozoic tree fern fossils could be described and identified as a species level. Such studies are, in these days, redefining classification criteria done by Japanese paleontologist, Ogura. That is, Korean researchers pointed out that the classification criteria of the tree fern fossils (Cyathocaulis) reported early from Chilgok were ambiguous, and the possibility that the two species were the same species was suggested. In addition, it is necessary to reorganize designated areas as a way to resolve social conflicts and civil complaints caused by various regulations that have continued for a long time.

• Journal of the Korean Applied Science and Technology
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• v.40 no.6
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• pp.1201-1212
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• 2023

This study aimed to analyze the changes in underwater anxiety and water safety consciousness among college students through participation in survival swimming education and the relationship between these changes and various factors. To achieve this, 200 college students who were participating in survival swimming education from universities located in the Busan-Ulsan-Gyeongnam region were selected as participants using convenience sampling. Among them, a final valid sample of 191 students was utilized. Data analysis was conducted using SPSS 25.0 statistical software, including exploratory factor analysis, reliability analysis, paired sample t-test, repeated measures ANOVA. The results are as follows: Firstly, college students who participated in survival swimming education showed a decrease in post-test underwater anxiety and an increase in water safety consciousness compared to pre-test. Secondly, the interaction between the groups based on the presence or absence of swimming education experience and time showed a significant effect only in the safety education, a sub-factor of water safety consciousness. Based on these results, the effectiveness of survival swimming education for college students could be confirmed, and further directions for expanding survival swimming education in university settings could be considered.

• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.1
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• pp.43-57
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• 2024

As coastal areas have a distinct nature with the interaction of the lands and waters, they attract people to enjoy and experience the natural environments physically and intellectually; this generates cultural ecosystem services. Coastal beaches are one of the most common coastal areas for cultural ecosystem services. The purpose of this study was to 1) estimate the economic values of cultural ecosystem services derived from coastal beaches, and 2) expand the estimated values into other beaches across the country using a benefit transfer method. We divided the values of cultural ecosystem services into five different categories based on an extensive literature review: recreation and tourism, landscape and aesthetic, educational, heritage, and inspirational values. The values of tourism and recreation, landscape and aesthetic, and educational services were estimated using the choice experiments. The attributes of the choice experiments consisted of conservation funds, litter, water quality, seascape, landscape, and biodiversity, and the data were collected through online surveys with visitors of 11 representative beaches in Korea. Heritage and inspiration services were estimated using a market goods method based on their expenditures. These values were transferred to 257 beaches across the country. Study results can be used for policy decisions on various restoration and conservation projects caused by coastal erosion and development and on the need and extent of public investments.

• Journal of Navigation and Port Research
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• v.48 no.1
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• pp.49-54
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• 2024

This paper investigated the impact of economic cycles in the shipbuilding industry on managerial performance of marine paint and coatings firms. As part of the upstream to ship construction, the marine equipment industry plays a critical role in determining the competitiveness of the shipbuilding industry. Despite a close interaction between the two sectors, the majority of research on the marine equipment industry has highlighted securing competitiveness edge and developing advanced technologies, paying little academic attention to the relationship between shipbuilding and managerial performance. In this regard, this paper examined how economic cycles in shipbuilding affected growth and profitability of marine paint and coatings firms. To this end, managerial performances of six marine paint and coatings firms for the period of 2003-2022 were analyzed in panel regressions. Results indicated that the shipbuilding economic cycle proxied by delivery amounts of Korean shipyards was positively associated with growth and profitability of marine paint and coatings firms. However, there was divergence in statistical significance by shipbuilding indicators. While coefficients of compensated gross tonnage, gross tonnage, and monetary amount were statistically significant, that of deadweight tonnage was not. Findings of this study imply that managerial performances of marine paint and coatings firms are affected by the amount of value added from the shipbuilding industry rather than its absolute size.

• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.4
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• pp.348-357
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• 2024

Maneuvering performance is crucial for fishing vessels, especially under operational conditions that involve frequent course changes and weight variations due to catch. Small vessel accidents account for approximately 60% of maritime incidents as of 2022, mainly attributed to collisions and stranding accidents due to insufficient maneuvering performance. Especially, accidents that occur on small vessels less than 10 tons account for about 65% of all accidents. The absence of international standards presents challenges in accurately evaluating the maneuvering performance of small vessels. In this study, a 4.99-ton small fishing vessel was selected as the target, and a 3d-cad model was created. The commercial numerical analysis program STAR-CCM+ was employed to establish a simulation environment for the vessel's maneuvring motion. Based on this standard loading conditions and weight distribution were considered, 10° / 10°, 20° / 20° zigzag tests and 35° turning test were conducted. The results revealed a tendency for decreased yaw and course-keeping performance and improved turning performance as the hull weight increased. However, in partial arrival and full load departure condition, the manoeuvering performance were relatively poor. Based on this, the need for evaluation of maneuvering and standardized criteria of maneuvering performance for safe navigation of small vessels is presented. Furthermore, it is expected that the evaluation results of maneuvering performance in this study can serve as fundamental data for establishing criteria for evaluating the maneuvering performance of small vessels.

• Journal of the Korean Society of Marine Environment & Safety
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• v.12 no.4 s.27
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• pp.293-300
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• 2006

Domestic laws such as Korea Marine Pollution Prevention Law (KMPPL) which has been mae and amended according to the conclusions and amendments of various international conventions for the prevention a marine pollution such as MARPOL 73/78 were reviewed and compared with the major contents of the relevant international conventions. Alternative measures for legislating new laws or amending existing laws such as KMPPL for the acceptance of major contents of existing international conventions were proposed. Annex VI of MARPOL 73/78 into which the regulations for the prevention of air pollution from ship have been adopted has been recently accepted in KMPPL which should be applied to ships which are the moving sources of air pollution at sea rather tlnn in Korea Air Environment Conservation Law which should be applied to automobiles and industrial installations in land. The major contents of LC 72/95 have been accepted in KMPPL However, a few of substances requiring special care in Annex II of 72LC, a few of items in characteristics and composition for the matter in relation to criteria governing the issue of permits for the dumping of matter at sea in Annex III of 72LC, and a few of items in wastes or other matter that may be considered for dumping in Annex I of 96 Protocol have not been accepted in KMPPL yet. The major contents of OPRC 90 have been accepted in KMPPL. However, oil pollution emergency plans for sea ports and oil handling facilities, and national contingency plan for preparedness and response have not been accepted in KMPPL yet. The waste oil related articles if Basel Convention, which shall regulate and prohibit transboundary movement of hazardous waste, should be accepted in KMPPL in order to prevent the transfer if scrap-purpose tanker ships containing oil/water mixtures and chemicals remained on beard from advanced countries to developing and/or underdeveloped countries. International Convention for the Control if Harmful Anti-Fouling Systems on the Ships should be accepted in KMPPL rather tlnn in Korea Noxious Chemicals Management Law. International Convention for Ship's Ballast Water/Sediment Management should be accepted in KMPPL or by a new law in order to prevent domestic marine ecosystem and costal environment from the invasion of harmful exotic species through the discharge of ship's ballast water.

• Journal of Navigation and Port Research
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• v.32 no.1
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• pp.47-56
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• 2008

With rapid growing of the Northeastern Asia, the interest for the connection of Infrastructure that was behind of interesting until now is getting larger. In a line of same connection, UN-ESCAP are forwarding transcontinental railway project, asian highway project et al.. And this study aimed at analysis on the effect that extended to a space by Korea-Japan undersea tunnel project. In aspect of a national land balanced-development to solve various problems such as overcrowding in capital region, unbalanced state by regions, weak exchange between South and North Korea, and weakness of national land basis to prepare for unification et al., this study consulted the economic potentiality model as a analysis method to examine an effect. In this analysis, I used 24 scenarios including all cases by combination of 3 scenarios for Korea-Japan undersea tunnel, 4 scenarios for transportation modes in the section of undersea tunnel, and 2 scenarios for adjacency infrastructure. Transportation modes in the section of undersea tunnel are railway, car-train, mixing way of railway and car-train, and mixing way of road and railway. Adjacency infrastructure applied railway and road. In all scenarios, Korea showed higher growth potentiality than Japan. Also, proposal plan C route relatively showed better in national land balanced-development than other proposal plans. The growth potentiality relatively appeared higher by buildup of a connection together with non-capital regions from the construction of Korea-Japan undersea tunnel. In aspect of Northeastern Asia, it resulted in a increasing of trade and chance of network formation in the region of Asia through infrastructure connection. But, in considering passenger and various factors that extended to the economic growth, this analysis have some limitation. Therefore, I hope that deep studies will continuously perform with various factors.

• Journal of Navigation and Port Research
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• v.32 no.1
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• pp.109-114
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• 2008

This study is about the status and comparison of recreational scuba diving certification system in Southeast Asia countries. For the collection of the information, the contents of the numerous corresponding Internet sites were utilized, related documents were surveyed. And to supplement the information extensive interviews were held with the representatives of tourism department of many countries as well as staffs of diving associations, resort operators and diving instructors during various 2007 Dive Expos held in Southeast countries. In this paper, the relation between scuba certification and international standards were introduced for better understanding of the certification system. The research result shows that the scuba diving industry plays an important role in their country's tourism and the certification market of the Southeast Asia has grown to be greater than 30% of the world total market. However due to the facts that the scuba activity is originated from the western world and the controlling headquarters of the most certification agency are also located there, Southeast countries cannot take any leading roles in the scuba diving policies and systematic issues. Accordingly any modifications or improvements are expected to be very difficult. Also while Europeans and Americans have launched the programs and organizations for the quality assurance by cooperating with the international standards, but no such activity has yet appeared on the surface in Southeast Asia. According to the investigation the necessity will become bigger in near future.