• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.29 no.6
• /
• pp.888-892
• /
• 1996

Anaerobic decomposition experiments were performed to know the effect of chemical composition and temperature for the production of volatile fatty acids (VFAs) from marine sinking particles. Sinking particles were obtained with sediment traps set in Aburatsubo Inlet, Kanagawa Prefecture, Japan, in February, May and August. Sinking particles collected in May were composed of higher fraction of chl. a than the other two months. February and May samples were used to perform the decomposition experiments. VFAs production rates were higher in May sample than February. The production rates increased with increase of incubation temperature, and order of production rates of four VFAs were acetate>n-butyrate>propionate>iso-butyrate at $10^{\circ}C\;and\;20^{\circ}C$. At $28^{\circ}C$, the production rate of propionate was higher than n-butyrate. Based on these results, it is considered that production of VFAs from sinking particles during anaerobic decomposition depends on the chemical composition and temperature.

• Journal of the Society of Naval Architects of Korea
• /
• v.42 no.3
• /
• pp.276-283
• /
• 2005

The cooperative production system was proposed as an efficient production system to reduce the ship construction cost and to enhance the competitiveness for small/medium sized shipbuilder in the previous paper. In viewpoint of cooperative production system, the specialization of the FRP ship sizes has already been accomplished to reduce the number of the hull molds by FRP shipbuilders of the Sapjin industrial complex located in Mokpo area in 2003. There also exist lots of effective methods, as a cooperative production system, to cut down the construction cost. In this study, an effective production system in connection with the super structure and outfitting members is proposed such as the standardization of those items and specialized company which intensively produces the super structure and outfitting members at the collectivization area for cooperative work.

• Proceedings of the KSRS Conference
• /
• 2004.10a
• /
• pp.562-563
• /
• 2004

Environmental management system has been constructed using by marine GIS, which is applied latest scientific algorithm, and fisheries related data for the citizens of the Jinhae Bay and executive officers. Through this system, we will get more easily marine environmental data, and production features of aquaculture farming areas.

• Journal of Fisheries and Marine Sciences Education
• /
• v.20 no.1
• /
• pp.36-45
• /
• 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 Korea Multimedia Society
• /
• v.21 no.3
• /
• pp.432-440
• /
• 2018

In this study, we propose a marine character prototype study for development of a marine character as digital contents. This study is a precedent study to build a marine character database with the production of digital contents based on "Jasan-urbo". "Jasan-urbo" is a representative cultural heritage that can highlight the value of Korean marine culture as the first illustrated book of marine creatures in Korea. Therefore, we examined the use value of "Jasan-urbo" through the content approach and looked at the visualization for character utilization and then designed a marine fish species classification standard model. Finally, this study proposed the possibility of discovering prototype sources for digitalization of Korean marine creature's resources.

• Journal of Chitin and Chitosan
• /
• v.22 no.3
• /
• pp.185-193
• /
• 2017

Red tide Heterosigma akashiwo (H. akashiwo), a microscopic alga of the class Raphidophyceae, causes extensive damage to all marine ecosystems. It is essential to reduce the damage to marine ecosystems for them to be used as a resource. In this study, we used organic solvent fractionation to obtain an ethyl acetate-methanol extract from H. akashiwo (HAEM80) and then evaluated its anti-inflammatory activity in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and a zebrafish model. HAME80 markedly inhibited the production of nitric oxide (NO) and prostaglandin $E_2$ ($PGE_2$). It also down-regulated the protein expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and decreased the secretion of interleukin-$1{\beta}$ ($IL-1{\beta}$) in LPS-stimulated RAW 264.7 cells. HAME80 reduced yolk edema and improved the survival rate of LPS-stimulated zebrafish embryos; in addition, the extract significantly reduced the production of ROS and NO and attenuated cell death in this model. Gas chromatography-mass spectrometry (GC-MS) of the extract was used to confirm the identity of peaks 1-20. Taken together, our data suggest that H. akashiwo is a beneficial anti-inflammatory agent.

• Journal of Marine Bioscience and Biotechnology
• /
• v.11 no.1
• /
• pp.23-28
• /
• 2019

For successful microalgal biodiesel production, the strain should be selected carefully. Fast growth rate and high fatty acid contents are desired traits for algal biodiesel production. In ocean cultivation of microalgae, seawater temperature slowly changes over seasons, and rotating algal strains in accordance with their optimal temperature could improve overall productivity. Additionally, use of indigenous strain is preferred to alleviate potential impacts on the environment. In this study, five strains of Tetraselmis sp. from nearshore of Youngheung Island, Incheon, Korea, were isolated during winter and characterized for their growth patterns and fatty acid compositions in the low temperatures ($5-15^{\circ}C$). The five strains showed various characteristics in optimal growth temperature, fatty acid contents, and compositions. Compared with a strain of Tetraselmis sp., isolated from Ganghwa island in a previous study, a rapid-growing strain with 237% higher biomass productivity and an oleaginous strain with twice higher fatty acid contents at $10^{\circ}C$ were isolated. The oleaginous Tetraselmis strain showed the highest fatty acid productivity among the strains, having 438% higher productivity than the previous strain. Using the new isolates in the seasons with low seawater temperature would improve microalgal fatty acid productivity in ocean cultivation.

• Journal of the Korean Society of Fisheries and Ocean Technology
• /
• v.50 no.1
• /
• pp.30-38
• /
• 2014

Hydro-acoustic survey was carried out to investigate the spatial characteristics of fish distribution near two artificial reefs (AO: large octagonal semi-sphere and AC: combined custom built) having different types in Jeju marine ranching area. The survey system consisted of scientific echo sounder (EK60), DGPS system, and ECDIS (Mecys). Field survey was conducted on August and October 2012 with star survey and line transect survey line method, and species composition was investigated from gill net fishing survey. The acoustic signals from individual fishes and small fish schools were mainly recorded around AO, but large and strong signals from large fish school were mainly detected in the top layer of and the water column near AC. The echogram suggest that the fish aggregation for the two types of AO and AC exist the significant difference in fish species and spatial distribution pattern.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.34 no.2
• /
• pp.156-159
• /
• 2001

The experiment was carried out to investigate the productivity of freshwater rotifer, Brachionus calyciflorus and marine rotifer, B. rotundiformis at various temperatures, initial inoculation and pH in a 5 L semi-continuous high density culture. Rotifers were fed by commercial condensed freshwater Chlorella. When pH was not controlled, average daily productions of freshwater and marine rotifers increased with temperature. The highest production, $44\times10^6$ rotifers, was achieved of B. calyciflorus at $32^{\circ}C$ and the possible production lasting period of B. calyciflorus was shorter than that of B. rotundiformis. Under the adjustment of pH at 7, the possible production lasting periods of B. calyciflorus and B. rotundiformis inoculated with 5,000 inds./mL were longer than those of rotifers inoculated with 10,000 inds./mL, and the daily production rate of the former was higher than that of the latter. The results from this study indicated that optimum density of the initial inoculation for the cultivation of B. calyciflorus and B. rotundiformis was 5,000 inds,/mL under the controlled conditions of pH 7 and at $32^{\circ}C$ in a semi-continuous high density culture, in terms of production rate and food cost aspects.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.30 no.4
• /
• pp.291-298
• /
• 2024

As an important fishing ground in the southern coast of Korea, Jinhae Bay is characterized by a high level of fisheries production. However, its marine-ecosystem has shifted owing to environmental changes such as industrial development and high water temperatures over the decades. This study analyzes the fisheries production, discards, mean trophic level, and fishing-in-balance index using annual fishing data from five regions surrounding Jinhae Bay for the period 2005-2022, as well as using additional forecasting trends by 2027 using ARIMA (Auto Regressive Intergrated Moving Average). The results shows, that the production in Goseong will decrease continuously by 2027, as compared with that in other areas. Additionally, byproduct management is considered necessary in Tongyeong. For the marine-ecosystem index, Tongyeong indicates stable catch ratio of large fish species and a fishing-in-balance exceeding 0. Finally, the annual catch variation for six pelagic fish species in Jinhae Bay by 2060 is estimated based on the IPCC climate-change scenario, in which the recent low level that decreased to approximately 20 thousand ton in early 2020 is projected to recover to approximately 40 thousand ton in the 2020s and 2040s, followed by an incremental decline by 2060.