• Journal of Navigation and Port Research
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• v.27 no.3
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• pp.259-266
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• 2003

Due to the growth of population and industrial development at the coastal cities, there has been much increase in necessity to effective control of the wastes into the coastal water and river. The amount of disposal at those waters has been increased rapidly ana it is necessary for us to track of it in order to keep the waterway safe and the water clean. The investigation and research in terms of water quality in these regions have been conducted frequently but the systematic survey of the disposed wastes at the bottom was neglected and/or minor. In this study we surveyed the status of disposed waste distribution at the bottom of coastal water and river from the scanned images. The intensity of sound received by the side scan sonar tow fish from the sea floor provides information as to the general distribution and characteristics of the superficial wastes. The port and starboard side scanned images produced from two arrays of transducers borne on a tow fish connected by tow cable to a tug boat have the area with width of 22m~112m and band of 44m~224m. All data are displayed in real-time on a high-resolution color display ($1280{\times}1024$ pixels) together with position information by DGPS. From the field measurement and analysis of the recorded images, we could draw the location and distribution of bottom disposals. Furthermore, we could make a database system which might be useful for navigation and fundamental for planning the waste reception and process control system.

• Korean Journal of Ichthyology
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• v.17 no.4
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• pp.264-270
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• 2005

The ichthyofauna and fish community structure were investigated at three areas in Lake Chungju from April to October 2004. During the surveyed period,32 two species belonging to 12 families were collected. Dominant species in number was hemibarbus labeo (relative abundance : 23.2%) and subdominant was Erythroculter erythropterus (12.1%). Siniperca scherzeri (9.2%), and Pseudogobio esocinus (8.6%) were also numerous. There were nine Korean endemic species belonging to six families including Acheilognathus yamatsutae. The number of fish species collected was 28 in Danyang, 17 in Jecheon, and 15 in Chungju. Highest dominant index calculated was 0.670 in Chungju, and highest diversity index calculated was 2.442 in the Danyang area. We need closer observation of population fluctuation of some species, including H. labeo, the dominant species by biomass in Lake Chungju.

• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.395-404
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• 2000

The gonadosomatic index (GSI), hepatosomatic Index (HSI), egg size distribution, gonad development and reproductive characteristics of venus fish, Aphyocypris chinensis, were examined during March 1997- March 1998 in agricultural waterways of the Sedo-myun, Puyo county, Chungnam Province, Korea. Annual reproductive cycle was classified into the following five successive phases by monthly changes in GSI and the characteristics of ovary: quiescent phase (January- February), secondary growing and mature phase (March-May), ripe and spawning phase (June-July), degenerating and resting phase (August-September) and primary growing phase (October-December). The hepatosomatic index (HSI) showed clear seasonal pattern with two separate peaks. However, it exhibited a negative correlation to changes of GSI values. The regression analysis suggested that fecundity showed a strong positive linear relationship ($r^2\;=\;0.91$, n = 34) with body weight. The sex ratio of female to male was 1.4 : 1 in the natural population during the study. The minimum reproductive size of female and male venus fish was 38 mm and 33 mm in fork length, respectively.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.40 no.3
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• pp.182-188
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• 2004

It has been, in general, known that the catching efficiency of a trammel net is better than that of a gill net because of the variability of catch species and size. In this stidy, A fishing gear test was carried out to analyze the catching efficiency of the gill net and the trammel net on the coast of Geomun-do of southern Korean waters and fish school aggregation was also investigated using a underwater video camera. CPUE of the gill net was 49.2% higher than the trammel net but fish species was 34.5% lower where there was no difference on the significance level of 5% by ANOVA test. Main catch species caught by the gill net were red seabream(Pagrus major) and triggerfish(Aluterus monoceros), skate ray(Raja Kenojei) and red seabream for the trammel net, and the average body length of red seabream was shorter than the trammel net. It was thought that the reason of higher catch in the gill net than the trammel net was a fish school which can be caught easily by gill net and the size of population was suitable for the gill net.

• Journal of Veterinary Clinics
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• v.29 no.1
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• pp.58-62
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• 2012

To protect aquatic animal health of importing countries from the potential risks associated with exotic diseases introduced through international trade of live aquatic animals, inspection of designated commodities at ports of entry is a critical component of the safeguarding system. The only way to be 100% confident that no fishes in a shipment are infected with a specific agent is to test every fish in the commodity imported with a perfect diagnostic test. For the majority of cases, this is unrealistic since the group of interest may very large particularly for aquatic animals, or imperfect tests are often available. It is, therefore, more common to test a fixed proportion of a group by preplanned sampling schemes. However, decision making based on results of testing the sample can provide quite a chance that infected groups may be misclassified as uninfected, depending on sampling strategy employed. The objective of this study was to determine the possibility that one or more fishes in the group imported being infected but tests negative after inspecting samples. This question is critical to government authorities to examine whether sampling plan is sufficient to achieve the purpose intended for. At fixed population size, the maximum number of infected fishes when all tests negative was decreased as the sampling fraction increased. The probability of including at least one undetected but infected fish in a group for negative tests increased with the number of fish tested or true prevalence. The risk was much lesser where high sensitivity test was assumed; when increasing test sensitivity from 0.9 to 0.99, this risk was dramatically reduced to about a tenth or a fourth for prevalence ranges from 2 to 10%, given sample size ranges from 10 to 200. Based on the preliminary analysis, the author concluded that current sampling plan testing 4-8% of the import proposal for human consumption still can yield high false negative results. Therefore, from the quarantine inspection point of view, an enforced commodity-specific sampling design that accounts for the cost of testing with an imperfect test at the specified design prevalence is urgent.

• Korean Journal of Ecology and Environment
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• v.34 no.2 s.94
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• pp.98-105
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• 2001

Two-monthold silver carps were cultured with seven algal species and zooplankton (Moina macrocopa) in the laboratory. The carps were reared in 10 L translucent cylindrical aquaria with algae and zooplankton for 8 days. The Moina effectively fed almost cultured algae: perfectly removed Cryptomonas (NIES-282) within 60 min. Both algal diets Cryptomonas and Fragilaria (NIES-391) significantly increased the Moina population ($r^2$>0.93, p<0.005), while Microcystis (MIES-90) and Oscillatoria (NIES-204) reduced the zooplankton ($r^2$=0.97, p<001). Fish removed about 50% of all algae for 52 hrs, even 60% of Microcystis still remained: all algae reduced ca. 5${\sim}$12% of initial weight. Furthermore, a continuous supply of algae with same density resulted in the death of fish, e.g. 11 days in cyanobacteria Microcystis. Therefore, the growth limitation of silver carp by algae indicates that zooplankton is of direct dietary contributor in planktivores feeding behavior.

• Journal of fish pathology
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• v.13 no.1
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• pp.67-73
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• 2000

This study was carried out to elucidate the preliminary ecosystem of the heterotrophic bacterial flora in Kunsan Bay located in western costal area of Korea. Samples were collected at 5 sampling stations. Among 123 bacterial isolates, 9 genera of bacteria were appeared as follows; Vibrio spp.(44 isolates/35.7%), Pseudomonas spp.(42 isolates/34.1%), Aeromonas spp.(11 isolates/8.9%), Moraxella spp.(9 isolates/7.3%), Enterobacteria spp.(6 isolates/4.8%), Bordetella spp.(3 isolates/2.4%), Alkaligenesis spp.(3 isolates/2.4%), Flavobacterium spp.(2 isolates/1.6%), and Staphylococcus spp.(3 isolates/2.4%) respectively. Total viable heterotrophic bacteria was ranged from $5{\times}10^3$ to $1{\times}10^5$ CFU/ml and the most abundant viable counts of bacterial population were showed at the stations 2 and 3. This result indicates that the coastal area around Kunsan bay is getting to contaminate far more by municipal wastewaters and industrial byproducts. and so the outbreak of the bacterial diseases will be increased in fish farms.

• Food Science of Animal Resources
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• v.31 no.2
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• pp.232-240
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• 2011

The effects of adding fish surimi to Appenzeller cheese on quality characteristics during ripening were investigated. Cheese samples were prepared with 1.0% surimi. Changes in chemical composition, lactic acid bacterial population, pH, non-casein nitrogen, non-protein nitrogen, water-soluble nitrogen, a consumer sensory evaluation test, chromaticity, texture, and proteolysis were monitored during ripening. The electrophoretic patterns of cheese proteins and the functional components originating from the surimi were investigated. Adding surimi did not affect the appearance or consumer sensory characteristics of the cheeses. Significantly higher amounts of crude fat and moisture were observed in the cheese supplemented with surimi than in cheese without added surimi.

• Korean Journal of Community Nutrition
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• v.14 no.6
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• pp.699-709
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• 2009

In order to identify valuable factors for improving dietary quality of Korean rural elderly, the consumption frequency of food groups, dietary habits and health behaviors related to nutrient intakes of the elderly over 85 of Sunchang County were studied. The 171 subjects (61 males and 110 females) were chosen from Sunchang Province by stratified sampling. Among food groups, the consumption frequency of meat and fish groups influenced significantly on their nutrient intakes than the other groups. The subjects consuming more than 4 times per week of meat or fish had significantly higher nutrient intakes level than the other groups. The group consuming milk and milk products everday was higher in vitamin $B_2$ intake level than the other groups. Among dietary habits, the groups with good appetite and regular mealtime compared with the groups with low appetite and irregular mealtime had significantly higher nutrient intake levels. The family type was the determining factor of nutrient intakes. The subjects living with family members consumed higher nutrient intakes than the subjects living alone. The smoking and the alcohol consumption themselves did not affect nutrient intakes, but the subjects having alcohol consumption frequently more than once a day had lower nutrient intakes than the others. The group with dentures did not differ significantly from the without denture group in nutrient intakes; however, those who had chewing problems showed the lower nutrient intakes compared to those who did not have chewing problems. The subjects with more than two kinds of clinical symptoms had lower nutrient intakes than the subjects with less than two kinds of clinical symptoms. These results indicate that the identifying factors for desirable nutrient intakes of rural elderly were characterized as appropriate consumption frequencies of meat and fish, good appetite, living with family, regular mealtime, chewing without difficulty, and low incidence of chronic disease.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1518-1522
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• 2006

In the present study, it was observed how the phage-host system that is naturally reproduced in activated sludge is affected by the host inoculation. The system of Microlunatus phosphovorus and its phages was selected as the phage-host system native to an activated sludge system operated for 19 days under sequencing anaerobic-aerobic conditions with glutamate as the main carbon source. The phage-host system related to M. phosphovorus was monitored by plaque assay for the phages and by fluorescent in situ hybridization (FISH) for the bacterial host. In addition, the whole phage structure was also monitored by pulsed-field gel electrophoresis (PFGE). During the first 9 days, the phage-host system was more or less steady at approx. 9% (FISH/ DAPI) for M. phosphovorus and approx. 10,000 PFU/ml for its lytic phages. Microlunatus phosphovorus JCM9379 was inoculated into the activated sludge on day 10. Right after the inoculation, M. phosphovorus was approx. 24% (FISH/DAPI) whereas its lytic phages dropped down to approx. 500 PFU/ ml. After the host inoculation (within 9 days), however, the phage-host system eventually reverted to its original level in each population. On the other hand, the whole phage structure was not significantly changed by M. phosphovorus inoculation but stable throughout the process operation. Only the minor change that four phage groups gradually became abundant after the host inoculation was observed.