• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.4
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• pp.558-568
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• 2023

The spatio-temporal distribution of the sand crab Ovalipes punctatus larvae was investigated in the Korean waters in 2019. Sea surface temperature (SST) was the lowest in February and highest in September. Sea surface salinity (SSS) was the lowest in September and highest in March. Further, sea surface chlorophyll a (SSC) was the highest in September. Larvae were distributed in the South Sea and coastal area of Jeju Island from April to June, and the abundance was the highest in May. The spatio-temporal distribution analysis suggested that larval groups showed a tendency to be dispersed over a wider area as the larvae developed, due to the increase in their swimming ability. The correlation analysis between environmental factors and larval density suggested that larvae appeared in the SST range 11.8-20.9℃ and SSS range 31.5-35.3 psu. The Megalopal stage appeared in a wider range of SST and SSS than other larval stages, possibly due to the increased environmental tolerance before settlement. Results of redundancy analysis (RDA) and Spearman's rank correlation analysis between the larval density by developmental stages and the environmental factors suggested that SST showed a positive correlation and SSC showed a negative correlation in the later stage.

• The Journal of Fisheries Business Administration
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• v.16 no.2
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• pp.19-51
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• 1985

• The Korean Journal of Malacology
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• v.26 no.1
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• pp.85-89
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• 2010

Distribution of Cephalopods was investigated in the Yellow Sea, Korea from February, 2006 to November, 2008. The species composition of cephalopods, consisting of 14 species and 19,789 individuals has been identified. The dominant species of the Yellow sea was Euprymna morsei. The dominant species of the northern part, middle part and southern part were Todarodes pacificus, Loligo spp. and Loligo beka.

• Fisheries and Aquatic Sciences
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• v.26 no.12
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• pp.689-697
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• 2023

This study used a multi-frequency acoustic method to assess the density and spatial distribution of dominant zooplankton, euphausiids and copepods, which are representative species of the zooplankton immigrating the sea around Republic of Korea. Acoustic surveys were carried out in the East Sea and South Sea from June 16 to 29, 2017, using the research vessel Tamgu 20th from the National Institute of Fisheries Science. From the results of the acoustic survey, the distribution of euphausiids was relatively higher in the East Sea than in the South Sea. Additionally, although the distribution of copepods was low in all areas, they were abundant in certain areas in the East Sea and the southern area of the Jeju Sea. Euphausiid and copepod density was estimated to be 1.2 g/m² (CV = 19.1%) and 2.8 g/m² (CV = 23.5%), respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.60 no.1
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• pp.18-26
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• 2024

In this study, we estimated the distribution density of giant jellyfish in coastal waters of Korea in 2023 and compared the occurrence of giant jellyfish over four years. In May, the giant jellyfish were mainly distributed in the waters of the Yangtze River outflow, and in July, they were highly distributed in the west of Jeju Island and near the south coast of Korea. In addition, when comparing the distribution densities of giant jellyfish in Korea over four years, both acoustic and sighting surveys showed that the highest density of jellyfish occurred in 2021.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.1
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• pp.48-55
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• 2016

The species composition and distribution of catches by dredge gear in the Yeongil Bay, Korea were investigated on a seasonal basis from February to November, 2015. Total catches consisted of 44 species and 35 families. They were 13 species of fish, 10 species of crustacea, 5 species of echinodermata, 5 species of gastropoda, 4 species of cephalopoda and 3 species of bivalvia. Major catch species was shellfish and had seasonal variations in catch. In spring and winter, the catch of ark shell (Scapharca broughtonii) was increased. Adversely, the catch of admas venus clam (Callithaca adamsi) increased in sunmmer and autumn. Species diversity indices was high as the value of 1.99 in spring, and low to the value of 0.34 in summer. In addition, multi dimentional scaling (MDS) indices also was high in spring as the value of 1.99. In summer, the index was low as the value of 0.34. Similarity analysis based on species data was transformed by fourth root. With the result of cluster analysis and MDS analysis, species was divided into two groups. The first group as Group A consists of winter and spring species and another was Group B made of species in summer and winter.

• Journal of Fisheries and Marine Sciences Education
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• v.19 no.1
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• pp.101-109
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• 2007

The school system of fisheries high school was proper to specialist objective school system in order to training for expert human resource development.Training a field of human resources development from fisheries high school is fallow; fisheries production, seamen's training, ship engine and refrigerator, marine electronic telecommunication and information, fisheries foods production and fisheries foods production and distribution, fishery fisheries self-management, marine distribution, management and conservation of marine environment, safety and marine prevention of disasters, apparatus of marine development, under water area development.A new department opening and each department was revised toward to department name and department character. The unit-lesson hour of curriculum according to specialist objective school system of fisheries and marine highschool was revised. professional subject 98 unit-lesson hour(52%), normality subject 90 unit-lesson hour(48%), and educational activity of professional subject 10unit-lesson hour, total training activity 10 unit-lesson hour. And the special objective school system need to revise curriculum of 208 total unit-lesson hour.

• The Journal of Fisheries Business Administration
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• v.39 no.1
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• pp.1-16
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• 2008

For the last few years, the wholesale market system in Japan has been experiencing a lot of changes in the related sectors. The greatest changes in the environments surrounding the wholesale market were enlargement of the producers' cooperatives, increase of fisheries products marketed in the outside of the wholesale market system, and management aggravation of the related businessmen, These changes resulted in the revision of the wholesale Market Law in 1999 to cope with the social needs successfully. Recently, fisheries wholesale markets in Japan have a few problems like declining of earning power, weakening of management constitution, etc. Consequently, Japanese government presents policy for enforcing the competition power through reform laws related with fisheries wholesale markets. Also the fisheries wholesale markets have been trying variety and active countermeasures like undertaking, merger, coalition, etc. to overcome the crisis.

• Journal of Fisheries and Marine Sciences Education
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• v.20 no.1
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• pp.36-45
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• 2008

The purpose of this study was to explore new fisheries-related jobs in the future. The study is based on a thorough literature review and in-depth interviews with experts in the fisheries industry. The major findings of the study were as follows: First, new fisheries-related jobs that surpass the fitness rating of 90% and earn more than 3 on the prospect scale are expected to be found mostly in professional fishery sectors. In the production and processing sectors, fishery quality control manager, marine product cooks, and raw fish cooks looked most promising. In the fishery marketing and distribution section, on the other hand, marine tour consultants, marine product distribution consultants, underwater guides, online marine product traders, marine sports consultants, and marine safety specialists ranked high on the list.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.24 no.1
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• pp.36-43
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• 1988

Boilers and diesel engines have many problems because their exhaust particles, i.e., soot have lots of bad influence on environment. And it's spray and flame have fundamentally axial symmetric shape. To investigate the relationship between fuel concentration distribution of spray and soot concentration distribution as well as temperature distribution of flame, we made a axial symmetric two phase spray-flame and analyzed the structure of is. The measuring method is the principle of the light extinction method for the spray-flame and onion peeling model is applied to analyze the radial distribution of fuel and soot concentration. The temperature of flame is measured by ø 0.4mm Pt-Pt.RH 3% thermocouple. The oils for the experiments are diesel oil and 10% water emulsified diesel oil. It was found that the soot concentration becomes higher as it comes near to the center of flame, and the fuel concentration does, too. And the soot concentration level of diesel oil is generally higher than that of the 10% water emulsified fuel. The maximum flame temperature of diesel oil is 1,17$0^{\circ}C$, however, 10% water emulsified diesel oil is 1,27$0^{\circ}C$.