• The Korean Journal of Malacology
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• v.20 no.1
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• pp.45-53
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• 2004

This study have conducted to calibrate the productivities on the mussel (Mytilus galloprovincialis) cultures in Jinhae Bay. Annual water temperature, salinity and dissolved oxygen have varied to 7.2-$25.9^{\circ}C$, 32.9-34.0 psu, 7.9-8.7 mg/l, respectively. In April, the smallest size of spat, 3.3 mm in shell length, have recruited, and 82.5 mm have recorded to the maximum. In summer, variations of growing up between individuals showed both shell length and weights at same cohort. Annual production at 2 m, 5 m, 8 m depth calculated to 10.91, 10.85 and 9.19 gWWt/ind./yr, respectively. Mussel cultivated in the upper part of the water column (two meter depth) were significantly longer and heavier than those in lower part (eight meter depth). After the recruitment, monthly production showed gradual increment at all positions during summer. As results, annual production of mussel cultivated seemed to be controlled by conditions of growing up in summer. Based on the productivities calculated to this study, the total annual production of the mussel cultivated in Jinhae Bay have estimated about 196 ton/ha/yr.

• Journal of Microbiology and Biotechnology
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• v.30 no.12
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• pp.1944-1949
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• 2020

Mutant sugar transporter ScGAL2-N376F was overexpressed in Kluyveromyces marxianus for efficient utilization of xylose, which is one of the main components of cellulosic biomass. K. marxianus ScGal2_N376F, the ScGAL2-N376F-overexpressing strain, exhibited 47.04 g/l of xylose consumption and 26.55 g/l of xylitol production, as compared to the parental strain (24.68 g/l and 7.03 g/l, respectively) when xylose was used as the sole carbon source. When a mixture of glucose and xylose was used as the carbon source, xylose consumption and xylitol production rates were improved by 195% and 360%, respectively, by K. marxianus ScGal2_N376F. Moreover, the glucose consumption rate was improved by 27% as compared to that in the parental strain. Overexpression of both wild-type ScGAL2 and mutant ScGAL2-N376F showed 48% and 52% enhanced sugar consumption and ethanol production rates, respectively, when a mixture of glucose and galactose was used as the carbon source, which is the main component of marine biomass. As shown in this study, ScGAL2-N376F overexpression can be applied for the efficient production of biofuels or biochemicals from cellulosic or marine biomass.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.7
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• pp.947-950
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• 2001

To improve the low content of crude protein and low quality fermentation of napiergrass silage, ensiling with phasey bean was examined. Napiergrasses, (Pennisetum purpureum cv. Merkeron), hybrid napiergrass (Pennisetum purpureum${\times}$ Pennisetum typhoides) and phasey bean (Macroptilium lathyroides cv. Murray) were cultivated in Fukuoka, Japan. The first growth of napiergrasses and phasey bean were harvested at 90 days of age and chopped into about 1 cm lengths. The mixing levels of phasey bean with napiergrasses were 0, 25, 50 and 75; 700 g of plant materials were ensiled into a laboratory silo (1.0 litre. polyethylene container) and incubated for 30 days. After opening silos, pH, total nitrogen (TN), volatile basic nitrogen (VBN) and organic acids (lactic acid: LA, acetic acid: AA, butyric acid: BA) were determined. The experiment was a factorial design of $2{\times}4$ with 3 replicates. The data were analyzed statistically by two-way analysis of variance. Without inclusion of phasey bean, lower quality was observed for hybrid silage than for Merkeron silage. The inclusion of phasey bean at the rate of 25% increased DM and TN, and decreased pH value, VBN/TN, AA and BA in both Merkeron and hybrid napiergrass silages. The value of pH, TN, VBN/TN, AA and BA were not significantly different among 25, 50 and 75% mixing levels of phasey bean. LA production increased significantly with the increase in phasey bean mixing level in both hybrid and Merkeron silages. At all mixing levels of phasey bean, LA production did not show significant differences between Merkeron and hybrid silages.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.2
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• pp.162-168
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• 2016

This study attempted to help determine Korean fishery policies by proposing improvement plans after examining the current regulations, fishing vessels, fishing gear and fishing methods of the middle sized trawl fishery in the East Sea for targeting only squid. In general, the size, engine horse power, and net length of the middle sized trawlers are between 50 and 60 GT, 1,200 and 1,600 PS, and approximately 165 m with four seamed trawl nets, respectively. While a jigging vessel attracted squids using lights, the trawler approached a jigging vessel. The trawler let the jigging vessel know its decision for fishing, and then jigging vessel rolled up jigs. The net of the trawler was casted at 45 degrees between the bow and the stern of the jigging vessel. Once the trawler towed close to the stern of the jigging vessel upon its passing of the jigging vessel, the bow of the trawler turned 45 degrees left again. Then, squid aggregations were entered into the net. When the cod end was passed a light vessel, the trawler hoisted the net up to the otter board. Then the trawler turned 180 degrees. It repeated three to five times of fishing operations as the previous method. We recommend that the regulations allow nineteen side trawlers to catch like stern trawler, as well as the cooperative trawler and jigging vessel operations.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.3
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• pp.232-240
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• 2016

Marine casualties originated from fishing vessels occupied about 71.2% of the whole marine casualties in Korea from 2008 to 2014, which has not changed much for a long time. Therefore, a pragmatic counterplan to decrease in casualties in fishing vessel is indispensable for reduction of marine casualties in Korea. Since the casualties occurred by fishing vessels may incline to a specific type of casualties according to the difference in the operating type; in this paper, 11 fishing types which occurred casualties frequently in numbers and occupied ratio were selected. Since the most frequent occurring casualties in fishing vessels were from collisions and fire explosion in statistics from KMST (2008~2014), the study focused on them. The collision is given a great deal of weight in all the casualties mostly due to the negligence of duty regardless of the job types. Gill netter, trap fishing boat, jig boat, multiple fishing boat and stow netter have their own specific causes of casualties in collision according to the operating types. The cause of fire explosion was mainly due to poor inspection and maintenance the electric cord. For this reason, it may be necessary for an operator to make strict precaution on the other vessels under way systematically, keep the regulation for preventing collisions, and for an engineer on watch to make a check the electricity periodically to reduce the fire explosion.

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.2
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• pp.193-208
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• 2005

The object of this study is to provide a framework of increasing the effectiveness of the R&D planning of experts in fisheries and the education of students with the theoretical background and analytical skills through the adoption of technology roadmapping process in the marine production industry. The study was conducted by fact-finding surveys and the response content for surveys obtained from each expert advisor in the field of fisheries and maritime affairs such as fishery industries, some government organizations and research institutes including the Ministry of Maritime Affairs and Fisheries (MOMAF), National Fisheries Research and Development Institute (NFRDI) and fisheries-related universities was analyzed. The major implementation tasks to effectively achieve the basic goals of technology roadmap for short and middle-term research and development in the fisheries production field are as follows: 1. Research in order to achieve the realization of community-based resource management fisheries or fishermen-oriented co-management fisheries with paradigm shift in fisheries management. 2. Research in order to derive the construction of cost reducing and manpower saving systems in fishery-related science, technology and engineering. 3. Research in order to create the high value-added fisheries products with a focus on the upgrading of processing, freezing and refrigerating facilities, the reduction of logistics costs and the minimization of distribution steps. 4. Research in order to achieve the realization and development of environmental-friendly fisheries and internationally competitive fisheries through restructuring the entire fishing industries, in particular, small-scale fisheries. 5. Research in order to achieve the effective utilization of fisheries resources with a new creation of clean and living marine environment by fisherman under the balanced management and protection of marine living resources and fishing grounds.

• The Journal of Fisheries Business Administration
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• v.36 no.1 s.67
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• pp.139-153
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• 2005

Marine fish aquaculture has been introduced on the East sea since 1964. The production volume of the marine aquaculture has been increasing drastically since 1990 with the technological improvements and the introduction of new species. However, the increasing costs of feed, seedlings and medical supplies and the decreasing prices due to the increase in the imports and domestic production have decreased the profits in the aquaculture business. Futhermore, the damage from the natural disasters such as red tides and typhoons has accelerated the exit from the business. Even though managing abilities to overcome the business crisis caused by the above factors are required, business managers based on the small scale family businesses do not have enough managing abilities to deal with the difficulties in the business. On the other hand, advanced countries in the marine aquaculture such as Norway have reached the stage where the managing abilities of marine aquaculture are similar to those in the manufacturing industry. And the number of large scale aquaculture farms with developed technologies and advanced marketing strategies in those countries is increasing. Considering that the marine aquaculture in Japan under the similar fishery systems of Korea has developed the state-of-the-art management skills or lead to large scale management, it is difficult to expect the decrease in the production costs under the small scale family business in Korea and this will lead to the decreasing competitive advantage over the imported seafood. Therefore marine aquaculture in Korea needs to increase the economy of scale to acquire the competitive advantage. This study addresses the possibility of introducing the large scale aquaculture system in Korea by analysing the factors and process of leading to large scale businesses in the aquaculture in Japan.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.3
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• pp.351-360
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• 2014

The experiments were carried out to decide the selective fishing gear of the shrimp beam trawl fishery. The model nets were made of General type, Double-level type and Grid type. The model experiments were carried out to test opening efficiency and towing tension. The experimental tanks were the flume tank [$8.0L{\times}2.8W{\times}1.4H(m)$] and the towing tank [$85L{\times}10W{\times}3.5H(m)$] in National Fisheries Research and Development Institute. The full scale experiments were carried out to compare the selectivity of General type net, Double-level type net and Grid type net in the southern sea of korea. The vertical opening (net height) of the model nets can be expressed as a function of the towing velocity as the straight line. The towing tension of the model nets can be expressed as a function of the towing velocity as the parabola. The shrimp catching rates of upper cod end in Boryeong and tongyeong were 78%, 9% respectively, but the rates of lower cod end were 23%, 91% respectively. The number bycatch rates of General type and Grid type were 23%, 11% respectively, and the weight bycatch rates were 34%, 31% respectively. A selective shrimp beam trawl net is Grid type in korea coastal sea.

• Microbiology and Biotechnology Letters
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• v.21 no.3
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• pp.207-213
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• 1993

Total 176 alginate-degrading bacterial strains were isolated from marine moluscus, marine echonodermata, seaweed, and soils. Among the isolates, five strains (No. 28, 51, 79, 135, and 145) had higher level of alginate-degrading activity. The isolate No. 28, 51, 79, and 135 were identified as the genus Enterobacter and the strain No. 145 as the genus Vibrio. We used these strains to examine the optimal conditions for the production of alginate-degrading activity.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2000.05a
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• pp.383-384
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• 2000

Most of the photoperiodic responses result in a sharp contrast between development in long and short days, so that qualitative observations are quite sufficient to establish that development is under photoperiodic control, and qualitative information of this type is all that is available for many of the responses (Dring 1984). However, we need to devise some quantitative measurement of the response in order to study the physiological mechanism of photoperiodic control. We report here the quantification of photoperiodic control of erect thalli production of Sargassum muticum in different daylength regimes. (omitted)