• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.59 no.2
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• pp.164-171
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• 2023

This study analyzed the flow inside floating seedling equipment for Scapharca subcrenata. Due to the aging society of fishing villages, it is impossible to continuously input the labor force. Therefore, it is necessary to improve efficiency. Scapharca subcrenata has high per capita consumption. It serves as an important aquatic food resource. Scapharca subcrenata culture tends to be highly dependent on the natural environment. Production of Scapharca subcrenata is difficult to predict with low stability. In the past, manpower directly installed bamboo nets in mudflats. The seedling equipment devised in this study is a floating type and can be freely moved on the sea according to the prediction of Scapharca subcrenata generation. The flow around the floating seedling equipment was analyzed by numerical analysis. The physical phenomena of the flow around the net inside the floating seedling equipment were visualized. As a result, the space between the floating seedling equipment and the bottom net and the space between the net groups showed a lower flow rate than the inlet flow rate. It is expected that the low flow rate of the floating seedling equipment will have a positive effect on the attachment of Scapharca subcrenata.

• Korean Journal of Environment and Ecology
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• v.30 no.5
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• pp.874-887
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• 2016

We surveyed bimonthly from April to October 2015 to understand the fish fauna and community structure in Wangpicheon. The collected species during the survey period were 40 species belonging to 15 families. Dominant species by number were Zacco koreanus (31.3%) and Rhynchocypris oxycephalus (14.7%). In biomass, the dominant species were Z. koreanus (29.2%) and Coreoperca herzi (8.6%). Also, nine endemic species (22.5%) including Squalidus multimaculatus and two endangered species (Lethenteron reissneri, Cottus koreanus) were identified. It was identified one introduced species (Oncorhynchus mykiss) from foreign countries for aquaculture. Compared with previous data, nine species were newly identified including L. reissneri, S. gracilis majimae, Pseudobagrus fulvidraco, O. mykiss, Chelon haematocheilus, Siniperca scherzeri, Acanthogobius lactipes, Luciogobius guttatus and Channa argus. Seven species (Rhodeus ocellatus, S. gracilis majimae, Hemibarbus longirostris, Pseudogobio esocinus, Microphysogobio yaluensis, Hemiculter eigenmanni and Cobitis hankugensis) introduced from other native waters in Korea were estimated. According to the analysis of the habitat characteristics of major migratory species (Tribolodon hakonensis, O. keta and Plecoglossus altivelis), O. keta was observed at station 11 and T. hakonensis at station 7, 10 and 11. These fishes have been mainly identified in the downstream. However P. altivelis was widely distributed from station 3 to 11. In the comparison of average standard length of P. altivelis at each station during the same period, populations collected from station 3 and 5 which are mid-upper area of the stream were $125.8{\pm}34.2mm$. Their growth was good compared with those collected from station 8 and 11 (mid-lower area): $80.2{\pm}16.6mm$. This difference in length comes from the artificial structures including weir, thus it is necessary to create a fishway that enables P. altivelis to pass around barriers for free movement and resource management.

• Journal of Microbiology and Biotechnology
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• v.29 no.5
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• pp.739-748
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• 2019

Cheonggukjang and chaga mushrooms have numerous health benefits, and have been used in alternative medicine. Therefore, a powder mixture of 98: Cheonggukjang and 2: Chaga extracts was fermented with Lactobacillus acidophilus KCTC3925 (FCC) and its anti-obesity effects in high-fat diet (HFD)-induced obese mice were determined. Five-week-old male ICR mice were fed a normal diet or HFD in the presence or absence of 3% and 5% FCC by weight (n = 10 per group). After 12 weeks, the mice were sacrificed, and the serum and tissue samples were collected for analysis. Body weight and epididymal fat pad weight were significantly lowered in the 3% and 5% FCC groups compared with those in the HFD control group (p < 0.01). FCC supplementation suppressed serum triglyceride and increased serum HDL-C levels (p < 0.01). Serum GOT, GPT, and leptin levels, hepatic COX-2 mRNA expression, and splenic COX-2 and IL-4 mRNA expression were significantly higher in the HFD groups than in the control group (p > 0.05); however, except for splenic IL-4 levels, the increases were significantly attenuated by FCC supplementation. Expression of ICAM-1, an aortic inflammatory marker, was significantly increased in the HFD group; this effect was suppressed in the 3% FCC group (p < 0.01) but not in the 5% FCC group. FCC suppressed the body weight and epididymal fat pad weight gain, as well as inflammatory responses in the liver and spleen of HFD-fed mice. Thus, FCC supplementation will be beneficial for the treatment of obesity-related effects.

• The Journal of Fisheries Business Administration
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• v.51 no.3
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• pp.1-15
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• 2020

The Korean government has been carrying out the marine ranch development project since 1998 with the purpose of responding to the decrease in coastal fishery resources and fishery income, preparing a systematic management system for the sustainable use of fishery resources and realizing advanced fisheries power by expanding and upgrading fisheries resource development projects. In addition, the government established the Korea Fisheries Resources Agency and promoted projects for the protection and management of fishery resources by increasing basic productivity by artificially creating marine forests in areas where whitening events occur. Since the project of building marine ranches and marine forests requires immense government financial support, it is important to estimate the economic value and thoroughly evaluate the feasibility of the project. In this paper, the project of non-market economic value of the development of marine ranches and the development of marine forests was estimated. CVM (Contingent Valuation Method) was applied as a methodology for benefits estimation. Prior to the analysis, a one-on-one interview survey was conducted with participation of 512 residents and 514 residents respectively for the project of creating a marine ranch and developing a marine forest. A DBDC (Double-Bounded Dichotumous Choice) model was applied in the WTP (Willingness To Pay) analysis model and the socioeconomic variables of the surveyor, such as sex, age, education and income, were reflected in the model. The economic benefits from the two projects, namely, building of marine ranches and developing marine forests were estimated to be equal to 4,608 won and 7,772 won per household per year, respectively. According to the results of the survey, it seems that respondents think that marine forests are more valuable than marine ranches. This is as a result of ordinary citizens' thought that the marine ranches are more cost-effective than the marine forests. The benefits estimated through this study can be used for analysis of economic feasibility prior to carrying out the project of building marine ranches and developing marine forests, and are considered to be the valuable for policy-making purposes and finding social and economic consensus.

• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.382-388
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• 2014

Shortfin eel (Anguilla bicolor pacifica) is a species of commercial importance and its production is greatly affected due to the infection by Heterosporis anguillarum. In this study, we evaluated the effect of H. anguillarum infection on the growth of Shortfin eel. A disease that trunk muscle of cultured shortfin eel, Anguilla bicolor pacifica, were irregular and resulted in death, breakout of the commercial eel culture farm. We observed that the trunk muscle of infected eels were irregular and represented white or yellowish externally. Histopathologically, a great numbers of large or small spores and sporophorocysts were also observed in degenerated muscle layer. The cloning of specific gene of H. anguillarum, encoding small subunit ribosomal RNA (SSU-rRNA) was amplified by the polymerase chain reaction(PCR) from the muscle lesion of diseased eel. The size of clone gene is well matched with the size of small subunit ribosomal RNA of H. anguillarum and thus confirming the infection by H. anguillarum.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.141-148
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• 2011

This feeding experiment was conducted to investigate the effects of dietary inclusion of various additives on growth performance, hematological parameters, fatty acid composition, gene expression and histopathological changes in juvenile olive flounder (Paralichthys olivaceus). Eleven isonitrogenous (49% crude protein) and isolipidic (10% crude lipid) experimental diets were formulated: no additives (Con); 5% kelp meal (Ke); 10% krill meal (Kr); 1% garlic powder (Ga); 1% citrus meal (Ci); 3% onion powder (On); 1% ginger powder (Gi); 1% mugwort powder (Mu); 1% licorice powder (Li); 1% wasabi powder (Wa); and a mixture (Mix) of these additives. Three replicate groups of juvenile flounder (average weight of 8.5 g) were fed one of the experimental diets to visual satiety twice a day for 15 weeks. The dietary inclusion of additives did not affect survival, weight gain, specific growth rate feed efficiency, daily feed intake, daily protein intake, protein efficiency ratio, hepatosomatic index and visceralsomatic index of the fish. Plasma triglyceride levels were significantly lower in fish fed the Ke, Ga, On, Gi, Mu, Li, and Mix diets than in fish fed the control diet. Plasma glucose, glutamic oxaloacetic transaminase and total cholesterol did not differ among dietary treatments. No significant difference was observed in fatty acid composition and lipid content of the dorsal muscle in fish fed the experimental diets. Myosin gene expression did not differ significantly among treatments after 5 weeks but was significantly lower in fish fed the Kr, Ci, Li, and Mix diets than in control group after 15 weeks. Histopathological analysis showed mild gill hyperplasia and mild necrosis of liver parenchymal cells in several individuals of each experimental group. These conditions were also observed in the control group and were not thought to be related to the inclusion of feed additives. The present findings indicate that the dietary inclusion of additives did not affect growth performance, fatty acid composition, gene expression, and histopathological changes in juvenile flounder. However, plasma triglyceride content may be reduced by supplementation with 5% kelp meal, 3% onion powder, 1% garlic powder, 1% ginger powder, 1% mugwort powder, and the additive mixture.

• Journal of the korean society of oceanography
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• v.33 no.3
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• pp.123-135
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• 1998

Cooperative scientific research in Antarctic has been successful since the International Geophysical Year 1957/1958. Presently, 43 nations have joined the Antarctic Treaty as consultative parties or acceding states, and other treaties and agreements have evolved to conserve the integrity and to manage the resources of the Antarctic ecosystem. Although yet to be designated, tourism areas in Antarctica are under consideration. Due to its remoteness and vast magnitude, Antarctica's science is slowly emerging. Satellite technology has enabled observation of the progression of the ozone hole above Antarctica. Mineral exploitation has yet to take place, as has the transport of Antarctic icebergs to some arid nations. On the other hand, both seal and whale exploitations have occurred, devastating these populations. The lessons learned from past human greed are used to design krill and squid fisheries, though the life histories of these organisms are yet to be adequately understood. An ecosystem approach to managing Antarctic resource exploitation is essential. Procuring the needed logistics to do so is daunting, requiring the highest degree of international cooperation and educational outreach to nurture the needed effective scientific and engineering talent, both natural and social.

• Journal of the Korean Ceramic Society
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• v.53 no.4
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• pp.429-434
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• 2016

Here, we introduce a means of utilizing waste oyster shells which were obtained from temporary storage near coastal workplaces as $CO_2$ adsorbents. The calcined CaO can be easily dissociated to $Ca^{2+}$ cation and $CO_3{^{2-}}$ anion by hydrolysis and gas-liquid carbonation reaction and converted to precipitated calcium carbonate (PCC) in algae-containing water. The calcium hydroxide and carbonation combination in algae-containing water significantly contributed to improving water quality which is very dependent on the addition amount of calcined powders.

• Journal of Advanced Marine Engineering and Technology
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• v.31 no.3
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• pp.301-309
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• 2007

Netherlands had suggested a uniform system to standardize and simplify EDI systems relating to the Arrival/Departure, stay, and clearance of ships, persons, and cargoes for the Facilitation of International Maritime Transport to the International Maritime Organization(IMO). Republic of Korea proposed the Framework of XML-based Single Window System for the simplified clearance of ships to the 32nd session of Facilitation Committee of the IMO. Accordingly the authors studied that the XML Infrastructure for Single Window efficiently supports the Single Window service and the business collaboration between business entities of logistics. The proposed XML Infrastructure designs to support the various document format translation and to easily manage. Therefore business entity using the proposed system has the effect of downing the resource and costs on using Single Window.

• Korean Journal of Ichthyology
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• v.21 no.sup1
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• pp.52-62
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• 2009

Environmental differences of each sea around the Korean Peninsula in terms of factors including topography and complexity of sea current may influence species and genetic diversity of marine fishes. Fish are naturally abundant in the frontal area where various currents or water masses meet. However, this food resource is prone to human overexploitation, threatening the marine ecosystem. New fisheries resources management strategies are needed. Such strategies require information about population structure obtained through morphological and genetic methods.