• Journal of fish pathology
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• v.22 no.2
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• pp.163-166
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• 2009

The ectoparasite ciliate Trichodina has been recorded from above 100 species of freshwater and marine fishes. In April 2009, we investigated the trichodia infection in 13 species of marine fishes captured by emplacement net and gill net in order to understand trichodina infection status among the natural fish populations along the Namhae-Gun coast area, the southen coast of Korea. Trichodina infection was observed in 10 out of 10 sea basses Lateolabrax japonicus, 2 out of 5 finespotted flounder Pleuronichthys cornutus and 1 out of a stone flounder Kareius bicoloratus. The sea bass infected with the parasite showed hypertrophy and exfoliation in gill epithelium. In addition, hyperplasia and lamellar fusion of gill filament were noticed among naturally affected sea bass.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.19 no.4
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• pp.295-302
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• 2007

Abnormally high waves occurring at the east coast of korea were observed at five field measurement stations and their characteristics were analyzed with the use of wind data provided by the Korean Meteorological Administration. The high waves occurred because strong Donghae twister that was developed by extratropical cyclone blew while high swell arrived at the east coast of Korea. At Sokcho, the most northern site among the five measurement stations, maximum gust speed was 63.7 m/s and significant wave height reached at its maximum of 9.69 m with the corresponding peak wave period of 12.8 s. The reason for appearance of the abnormally high waves is that high swell continued while the twister blew strongly. Moreover, the wind direction was the same as the direction of swell propagation, which maximizes the increase of wave height due to superposition of swell and wind-generated waves. On the east coast of Korea, outbreak of this type of storm waves is very probable in winter season so that it is requested to establish a countermeasure of minimizing possible damage caused by the storm waves.

• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.3
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• pp.18-24
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• 2017

Appropriate selection of the starter is essential for successful starting of the gas-turbine engine. Thus, aerodynamic drag during starting phase should be analyzed to assess the feasibility of the starter. In this paper, aerodynamic drag is modeled based on the speed profile from the engine coast down test, and it is scaled with respect to the target engine by comparing the compressor load. Afterward, the govern equation of the starting phase is developed with the torque model of the starter, and the design scheme to select the feasible starter will be finally suggested. The proposed model of starting phase will be useful to perform a preliminary design of the starting system of the gas-turbine engine.

• Fisheries and Aquatic Sciences
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• v.4 no.4
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• pp.219-228
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• 2001

Surface sediments (0- 5 cm), mussels (Mytilus coruscus and M. edulis) and oysters (Crassostrea gigas) were sampled at 20 stations in Korean coast during a period of February to July 2000. Samples were analyzed for polycyclic aromatic hydrocarbons (PAHs) content using gas chromatography coupled to mass spectrometer detector (GC/MSD). The sediment $\sum PAH$ concentration varied from 7 to 1,214 ng/g dry weight and the level of carcinogenic PAHs of six species ranged from 1 to 563 ng/g dry weight in surface sediments. In organisms, the levels of $\sum PAH$ were in the range of 63-876 ng/g dry weight and the concentrations of carcinogenic PAHs of six species were in the range of 4-582 ng/g dry weight. The highest PAH concentrations in sediments and organisms were in samples from Station 5 in Pohang coast and Station 8 in Jinhae coast, respectively. $\sum PAH$ concentrations in sediments and organisms collected from Korean coast were slightly low or comparable to those in other countries. The contribution of ring aromatic groups to sum of 16 PAHs in sediments and organisms showed a similar pattern for most stations. In sediments, the predominant contributions were four and five ring aromatics like fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene and benzo[a]pyrene. In the organisms, four ring aromatics like fluoranthene, pyrene, benzo[a]anthracene and chrysene were predominant PAH species. Several molecular indices such as phenanthrene/anthracene, fluoranthene/pyrene and LMW/HMW ratio were used to identify the origin of PAH contamination in sediments. The results indicate that PAHs of Korean coast were mainly of pyro1ytic contaminants with slight petrogenic input. A high correlation within individual PAH compound in marine sediments was observed, while correlation in organisms showed a highly significant relationship for heavier molecular weight PAHs.

• ALGAE
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• v.17 no.3
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• pp.161-170
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• 2002

The vegetative and reproductive features of Grateloupia filicina (Lamouroux) C. Agardh (Cryptonemiales, Halymeniaceae) from different parts of the Indian Coast were studied. The plants grow in wide range of habitats and showed a lot of morphological variations. The development of the thallus is multiaxial type and the medullary region is composed of irregular, branched and stellate shaped cells. The gametophytic plants are dioecious and the male plants are smaller compared to female plants. The carpogonial branch is two-celled and formed on an a accessory branch system known as ampulla. Cystocarps are spherical to sybspherical with distint ostioles and scattered on the thallus surface. Tetrasporangia are common and tetraspores are either cruciate or decussate. Bisporangia are occasionally encountered. Our study suggests occurrence of two intraspecific taxa of G. filicina i.e.: var. luxurians and var. filinina from India coast.

• Fisheries and Aquatic Sciences
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• v.11 no.1
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• pp.41-49
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• 2008

Internal waves and internal tides occur frequently along the eastern coast of Korea. During the spring-tide period in April 2003, the East Korean Warm Current (EKWC) flowed near the Korean East Coast Farming Forecast System (KECFFS; a moored oceanographic measurement system), creating a strong thermocline at the intermediate layer. Weakened stratification and well-mixed water appeared frequently around the KECFFS, with duration of approximately 1 day. The results suggest the following scenario. Baroclinic motion related to the internal tide generated high frequency internal waves around the thermocline. The breaking of those waves then created turbulence around the thermocline. After well-mixed water appeared, a current component with perpendicular direction to the EKWC appeared within the inertial period. The change in stratification around the KECFFS locally broke the geostrophic balance as a transient state. This local vertical mixing formed an ageostrophic current within the inertial period.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2004.08a
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• pp.54-63
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• 2004

There are two principal routes for the Asia-North America containerized cargo, that of Asia-West Coast and Asia-East Coast. On the West Coast, the Asia-Los Angeles, dominate the commerce, whereas on the Asia-East Coast it's the Panama Canal. Each of these routes has different characteristics. All are similar in that each is the door to the commerce of containerized cargo originating in Asia; each combines maritime and overland transportation; each has important intermodal connections and is able to distribute cargo throughout the West and East Coasts of the United States. Each route also has its port of preference that has the necessary infrastructure, equipment and intermodal connections. For example, in the case of the Port of Los Angeles, in spite of some of its advantages, it has several serious problems due to the interminable containerized cargo traffic that must be solved rapidly and satisfactorily in order to progress. In this paper, we would like to show the problems of two main routes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.49-54
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• 1978

The cold water mass appeared in offshore of the east coast of Korea in summer season was studied in aspect of chemical oceanography. Such a typical relationship between phosphate and dissolved oxygen as shown in the upwelling regions could not be found in the east coast except around the Kampo coast, southern part of the east coast. It is possible to isolate the North Korean Cold Water from tile proper water of tile Japan Sea by using $\sigma_t-O_2$ diagram. The origin of the cold water mass in offshore of the east coast of Korea in summer is not mainly due to the development of upwelling of the proper water of the Japan Sea but thesouthwardflolvingoftheNorthKoreanCold Water.

• Magazine of the Korean Society of Agricultural Engineers
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• v.43 no.1
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• pp.75-86
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• 2001

North Korea reported that tideland reclamation projects had been successfully constructed and/or under construction during the period of the third development scheme(1987∼1993), which were 28,400ha in 9 project areas: 8 projects along the western coast and one in the eastern coast. In this study eight projects located in western coast were investigated in order to confirm the detail of works, construction stages and difference from our project formulation methods using the topographic maps published in different years and the recent sattelite image data especially Lansat TM and SPOT PN. Intensity-hue-saturation (IHS) method was adopted to merge two sattelite data for the image enhancement of remote sensing. Construction stages of sea-dikes, land consolidation for paddy and salt pan, reservoir for irrigation and desalinization and the present land use were investigated and estimated the acreage of the development areas. The total gross project areas of 38,105 ha: 16,555 ha completed for paddy or salt pan, 16,826 ha under construction, and 4,724 ha under planning were confirmed, although the area of 27,100 ha in 8 projects were reported to be completed or ongoing on the bimonthly journal of N. Korean Trend published in 1994.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.5
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• pp.486-492
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• 2012

In the late 1970s, the National Fisheries Research & Development Institute (NFRDI) started cetacean research to submit the Korean whale catch record to the International Whaling Commission. This continued until the moratorium on commercial whaling in 1986. The NFRDI resumed cetacean research with a pilot whale sighting survey in 1999. Subsequently, the NFRDI has conducted 53 cetacean sighting surveys within the Korean exclusive economic zone between 2000 and 2010. The surveys took a total of 760 days and cruising for 23,866 nautical miles. The finless porpoise Neophocaena asiaeorientalis was sighted most frequently (735 times), followed by the minke whale Balaenoptera acutorostrata (396 times), the long-beaked common dolphin Delphinus capensis (102 times), and the Pacific white-sided dolphin Lagenorhynchus obliquidens (27 times). Minke whales were distributed in the Yellow Sea and coastal area of the East Sea from spring to fall. Pacific white-sided dolphin sightings were restricted to the middle and upper coastal areas of the East Sea in summer. Common dolphins were sighted from east of the southern coast to the eastern coast of the Korean Peninsula from spring to fall. Finless porpoise occurred in all Korean coastal areas, except the middle and upper eastern coast.