• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.6
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• pp.856-861
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• 1996

The occurrence of TTX in ciliated protozoa was investigated in order to clarify tetrodotoxin (TTX) accumulation mechanisms in marine organisms. Tissue culture bioassay, HPLC, and GC-MS analyses confirmed the occurrence of TTX in Euplotes mutabilis and also in bacteria isolated from the culture medium. Fluorescently labeled bacteria (FLB) were prepared with those bacteria, and predation by E. mutabilis was observed. The results indicated that TTX in bacteria can be transferred to higher trophic levels through the food chain.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.10a
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• pp.311-312
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• 2012

A writing on local culture of Gi-jang province, Busan and providing marine culture by using a lignthouse as a source of tourism.

• Journal of Navigation and Port Research
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• v.47 no.4
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• pp.191-201
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• 2023

The provision of onboard Internet services is recognized as one of the measures to enhance the appeal of seafarers and improve seafarer welfare. This study aims to investigate the influence of seafarers' leisure activities using the Internet on shipboard culture. Shipboard culture was examined using Hofstede's cultural dimensions theory. An empirical analysis was conducted on crewmembers regarding their Internet-based leisure activities and the shipboard culture. As a result, it was observed that sociability activities through the Internet while onboard significantly influenced power distance, uncertainty avoidance, and long-term orientation. The investigation of shipboard culture revealed uncertainty avoidance, masculinity, and long-term orientation, along with low power distance and individualism cultures. In addition, an analysis of shipboard culture according to seafarers' characteristics showed significant differences in certain shipboard cultures based on seafarers' attributes.

• Journal of Microbiology and Biotechnology
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• v.32 no.11
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• pp.1416-1426
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• 2022

The need to discover new types of antimicrobial agents has grown since the emergence of antibiotic-resistant pathogens that threaten human health. The world's oceans, comprising complex niches of biodiversity, are a promising environment from which to extract new antibiotics-like compounds. In this study, we newly isolated Pseudomonas sp. NIBR-H-19 from the gut of the sea roach Ligia exotica and present both phenotypes and genomic information consisting of 6,184,379 bp in a single chromosome possessing a total of 5,644 protein-coding genes. Genomic analysis of the isolated species revealed that numerous genes involved in antimicrobial secondary metabolites are predicted throughout the whole genome. Moreover, our analysis showed that among twenty-five pathogenic bacteria, the growth of three pathogens, including Staphylococcus aureus, Streptococcus hominis and Rhodococcus equi, was significantly inhibited by the culture of Pseudomonas sp. NIBR-H-19. The characterization of marine microorganisms with biochemical assays and genomics tools will help uncover the biosynthesis and action mechanism of antimicrobial metabolites for development as antagonistic probiotics against fish pathogens in an aquatic culture system.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.50 no.4
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• pp.542-550
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• 2014

We investigated biomass, diatom species and fucoxanthin contents as cell growth, fatty acid and amino acid contents as nutritional composition of diatoms attached on plate to confirm effects of light emitting diodes (LEDs) due to block off natural light. In the single LED irradiation, biomass showed significantly higher to $30.0{\pm}6.48mg/m^2$ in white LED than that of others (P<0.05). The dominate diatom species was Navicula cancellata. Their lipid contents showed significantly higher to $112.9{\pm}19.23ug/mg$ dry matter (DM) in control than that of others LEDs. But eicosapetaenoic acid (EPA) contents showed significantly higher to $3.3{\pm}0.62ug/mg$ DM than others, but not significantly differed with natural control light treatment (P<0.05). And total protein contents are higher in control and blue LED light than that of others, but essential amino acid contents showed significantly higher to $3.2{\pm}4.8%$ in control (P<0.05). In mixing light with natural and LED light, biomass showed $2.6{\pm}0.22mg/m^2$ in blue LED (P<0.05). Fatty acids contents were not significantly differed with all treatments. Amino acid contents showed to $11.0{\pm}0.33ug/mg$ DM in white LED (P<0.05), but not significantly differed with others LED lights (P>0.05). Therefore, we could suggest that irradiation of blue LED in natural light very benefit to diatom culture for larvae of sea cucumber and abalone and do on.

• Ocean and Polar Research
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• v.34 no.2
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• pp.125-135
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• 2012

To evaluate the algicidal impact of a newly developed algicide thiazolidinedione derivative, TD49, on dinophyceae Akashiwo sanguinea in aquatic ecosystems, tentative culture experiments for the target species were conducted in small (SS), middle (MS), and large scale (LS) culture vessels. When TD49 was introduced at the final concentration of $2{\mu}M$ in SS and MS, as well as $1{\mu}M$ in LS, the abundance of A. sanguinea decreased significantly in all the treatments. On the other hand, total phytoplankton abundance, except A. sanguinea in the TD49 treatments, gradually increased with culture time, which implies that a cell destruction of A. sanguinea by TD49 is a major cause of the population growth by other phytoplankton species. Also, A. sanguinea was easily destroyed, which was likely to be a source of extracellular substances. In particular, a pH decrease was significant in the treatments than in the control, which indicates that the water in the treatments has been acidified, due to an increase in the heterotrophic metabolisms of bacteria and degradation of A. sanguinea cells. Our results indicate that the TD49 substance is the potential agents for the control of A. sanguinea in the enclosed and eutrophic water bodies.

• Fisheries and Aquatic Sciences
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• v.14 no.4
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• pp.371-378
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• 2011

Juvenile red seabream (mean body weight 29.0 g) were reared in recirculating culture systems with three different biofilter media, sand (SF), polystyrene microbeads (PF), and Kaldnes beads (KF). The efficiencies of the three different biofilter media were also tested. The SF was fluidized, and the PF and KF were trickled. All treatments were duplicated. The volumetric removal rates of total ammonia nitrogen by SF, PF, and KF were 193.8, 183.9, and 142.6 g $m^{-3}day^{-1}$, respectively, and those of nitrite nitrogen ($NO_2$-N) were 113.4, 105.9, and 85.8 g $m^{-3}day^{-1}$, respectively. The TAN and $NO_2$-N removal rates of KF were lower than those of SF and PF (P < 0.05), but there was no significant difference in these rates between SF and PF (P > 0.05). Among the biofilters used, only KF showed total suspended solid (TSS) removal capacity. The TSS removal efficiencies of SF and PF were negative. The growth rates of fish in SF were significantly higher than those in KF but not higher than those in PF. There was no difference in growth rate between fish in PF and KF. The specific growth rate and feed conversion efficiency of red seabreams in KF were lower than those in SF and PF, but there were no significant differences between SF and PF. These results indicate that sand and polystyrene microbeads are recommended for red seabream culture in a recirculating system.

• KIPS Transactions on Computer and Communication Systems
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• v.5 no.9
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• pp.247-260
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• 2016

Sensor networks have been used in many applications such as smart home, smart factory, etc. based on sensor data. Sensor networks can change system requirements and architectures depending on their application areas. Currently, sensor network application cases in ocean environments are very rare because the ocean environments have much difficult accessibility more poor conditions, higher wave heights, more frogs, much heavier salinity, etc., compared with ground environments. In this paper, we propose the requirements, architecture and design of a sensor network system for the littoral sea cage culture monitoring and we also introduce its operation results through the development. The developed system based on our research provides users with functionalities to extract, monitor, and manage underwater environmental conditions suitable to littoral sea cage culturing of fishes.

• Korean Business Review
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• v.22 no.2
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• pp.157-179
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• 2009

This papers aims to focus on the city marketing as the green growth policy strategies using a case study of Gangneung City, Republic of Korea. In the case study it was verified the fields of urban growth including ecology, culture, alternative and recycled energy, green transportation system. The implications of the study were as follows: First, the city government had regenerated the coastal pine forest through removing unlicensed buildings which were squatted down in decades. Secondly, the city government has recognized the value of culture that possessed various types of cultural asserts. Thirdly, it is possible to use and produce the ocean energy with the tidal power plant, wind power plant and green deep water because Gangneung City has the ocean-oriented image and is located the coastal region. Lastly, the city government has been utilizing the LED traffic light using solar heat and is going to apply the green car like an electric car. This paper indicates the importance of the alternatives of the green growth-oriented policy through city marketing using the concept of culture and ecology. The city government will strive after an advanced triple bottom line with the ecological sustainability, cultural diversity and economic effectiveness in the near future.