• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.6
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• pp.597-605
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• 2013

This study was conducted in warty sea squirt farm, Jindong Bay(10 stations; July, October, January, April) for the culture period of Styela clava, Styela plicata. We utilized water temperature, chlorophyll a, suspended particulate matter, hydrodynamics, salinity and dissolved oxygen saturation for the suitability assessment of warty sea squirt farm. Newly, Life Requisite Suitability graphs were made for the correlation between the growth of Styela clava, Styela plicata and farm environment. As a result of the assessment for Habitat Suitability Index, western bay(HSI 0.32~0.41) show values higher than eastern bay(HSI 0.19~0.27). This result shows the high correlation with the unit production of Styela clava, Styela plicata($R^2$=0.834, P<0.01). This could be helpful for fishery management for the sustainable productivity through the scientific suitable site assessment.

• Korean Chemical Engineering Research
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• v.48 no.3
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• pp.327-331
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• 2010

Porcine placenta was treated with alkali, acid and enzyme treatment to obtain extracts. Heavy metal contents such as Pb, As, and Hg were low enough to satisfy cosmetic agent standard. As a result of safety test(MTT assay), porcine placenta extracts showed over 80% of cell viability at $50{\mu}g/ml$, and cell toxicity was relatively lower. From antioxidation test using DPPH free radical scavenging assay, antioxidation effect was highest as 63% at $50{\mu}g/ml$ when porcine placenta was treated with alkali in pH 9. From whitening effect test using tyrosinase inhibition assay, tyrosinase inhibition effect was 30% at $50{\mu}g/ml$ concentration in alkali treated procine placenta, however, the efficiency was lower compared with arbutin or vitamin C. In anti-wrinkle effect test from elastase inhibition assay, elastase inhibition effects were 20~30% at $50{\mu}g/ml$ for 5 kinds of porcine placenta treatments, which was superior to standard, and especially, protease treated extracts showed best results. Skin formulation including 1% porcine placenta was made and the formulation was very stable for temperature and storage period. From this research, porcine placenta extract showed high potential for anti-wrinkle functional cosmetic agent.

• The Korean Journal of Mycology
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• v.26 no.2 s.85
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• pp.187-193
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• 1998

The effects of medium, incubation temperature, incubation period, pH of medium and $CO_2$ ondition during mycelial growth were investigated to study the factors associated with the formation of oidia in Flammulina velutipes. Oidia formation was increased when mycelial growth was poor, while oidia formation was inhibited in optimum condition of mycelial growth. Mating type of oidia was investigated to examine the effect of oidia formation on dikaryotic strain. Di-mon matings between oidia strains and original dikaryotic strain were carried out. Monokaryotic strains derived from oidia showed only one genotype. Seventy percent among Dimon mating strains showed slow mycelial growth and low yield of fruit-body, but others showed similar or high mycelial growth and yields in comparision with original dikaryon strain. One strain from di-mon mating demonstrated some differences in isozyme band pattern.

• Food Science and Preservation
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• v.14 no.1
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• pp.94-99
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• 2007

To investigate the effects of Pichia anomala SKM-T and Galactomyces geotrichum SJM-59 on Baechu kimchi fermentation, lyophilized yeasts were added to Baechu kimchi and co-cultured at room temperature ($20{\pm}2^{\circ}C$) for 7 days. Desirable pH and acidity levels appeared by 3 days of fermentation in both the control culture and that with added G. geotrichum SJM-59. Furthermore, the culture with G. geotrichum SJM-59 sustained a desirable pH and acidity level until 5 days of co-culture. The pH of the culture with P. anomala SKM-T decreased slowly and was significantly higher than that of control throughout the experimental period. As fermentation time increased, the acidity of the culture with P. anomala SKM-T increased gradually. However, this culture maintained a desirable acidity level throughout the experiment. The number of lactic acid bacteria in the culture with P. anomala SKM-T was higher than in the culture with G. geotrichum SJM-59, or the control culture, throughout the experiment. The highest LA/TM ratio appeared after 3 nays of fermentation in the control culture, and on the 5 day of the yeasts added co-cultures. On sensory evaluation, no differences were detected between control and the culture with G. geotrichum SJM-59 arter 3 days of fermentation. The co-cultures with yeasts received high marks in umami taste. The co-culture with P. anomala SKM-T showed better texture properties than did the control culture. It was considered that fermentation times were delayed by addition of G. geotrichum SJM-59 or P. anomala SKM-T to Baechu kimchi fermentation.

• The Korean Journal of Malacology
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• v.30 no.1
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• pp.1-8
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• 2014

Oxygen isotope analysis was carried out on a oyster (Crassostrea gigas) from the neolithic age Gagok-ri shell midden site, Dangjin, Korea to determine the seasonality of shellfish gathering and site occupation. Isotope samples were taken from the hinge section of the left valve of the oyster. The isotope values of the shell range from -2.02‰ to -6.05‰ vs PDB. The isotope profile shows a seasonal temperature cycle, providing information related to seasonality of shellfish gathering. The isotope values towards the edge of the hinge are gradually increasing, suggesting progressively cooling and a fall period of shell gathering and site occupation. The result shows that the oxygen isotope analysis using oyster shell hinges can be used for archaeological seasonality studies.

• Korean Journal of Construction Engineering and Management
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• v.7 no.2 s.30
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• pp.71-80
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• 2006

It is required to study systematical on the concrete quality management to extend structure life because rebuilding effect is reducing under present condition of large sized and high stories structure. Concrete, which shows its intensity by hydrating action and a big change in quality according to hot weather and temperature, produces a lot of quality problem under hot and cold weather. Because of each specification and construction plan which does not have basic standard on site, concrete's quality is irregular and makes some defect. As a result, Dae-gu is fumed out to be the longest area after investigating application period and days focused on 8 cities weather information about t relationship between hot weather circumstance and construction environment. Therefore, we first surveyed the curing construction processing in the region and found out the problem of quality management. Then figure out the way of solution. Moreover, we integrated curing quality management, which is applied differently to each site, to have equal quality and to reduce defect from construction site. And then, based on various test of construction condition and analysis of quality management item, we suggest effective concrete quality management to make curing construction standard guide and plan under hot weather.

• Korean journal of applied entomology
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• v.57 no.2
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• pp.87-95
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• 2018

Nosema spp. (NS) causes severe problems to honey bee colonies including the death of the highly infected ones. Searching for effective materials to control this parasite is very important. The objectives of this study were to identify the calendar for the prevalence of NS and other bee diseases, and to test the efficacy of three materials: diluted honey mixed with lemon juice (M1), chamomile extract mixed with sugar syrup (M2) and sutrivet mixed with sugar syrup (M3) against Nosema. To realize these objectives, diseases of brood and adult honey bees were surveyed over one year. Also, the efficacy of M1, M2 and M3 against Nosema was evaluated under field and laboratory conditions. The results showed that few diseases for immature and mature stages of honey bees were recorded. NS was detected during winter and spring in link with low temperature and high relative humidity. Under field conditions, M2 reduced the infection by 36.66% while M3 by 23.33% and finally M1 by 13.33%. In the laboratory, the highest efficacy was to M2 followed by M1 and finally M3. The three materials impacted the percentage of survived bees significantly higher than infected bees without any treatments over the experimental period. The study suggests the potential role of chamomile as a natural material to control NS.

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.480-490
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• 2001

The soil-air exchange processes of Hg were investigated from the Hari area of Kang Hwa Island during the late March 2001. In the course of our study, we determined the concentration gradients of Hg and combined these gradient data with micrometeorological components to derive its fluxes. Results of our study indicate that the concentration levels of Hg in the study area are notably lower than those typically found in urbanized areas of Korea. However, the computed fluxes were seen to be significantly larger for relatively remote areas, reaching over 200 ng/m$^2$/hr. Comparison of environmental conditions shows that the concentrations of most pollutant species including NO$_X$ and PM were significantly higher during emission, while meteorological conditions were characterized by high temperature and low humidity. Results of correlation analysis also indicate that such pollutants as hydrocarbons, nitrogen oxides, and PM generally exhibit strong positive correlations with Hg-related parameters during emission events, while such relationships were reversed during dry deposition events. The results of our present study suggest the possibility that the concentrations and fluxes of total gaseous Hg observed during deposition events can be influenced by the processes that are also important for the fine, rather than coarse, size fraction of particles.

• Journal of Aquaculture
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• v.11 no.1
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• pp.99-103
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• 1998

Artemia often observed as a co-existing organism in the mass culture tank of marine rotifer. The rotifer and Atremia are commonly used as food organisms in the marine fish larvae rearing. In this study, interspecific relation between the rotifer Brachionus rotundiformis (formely called S-type) and anostracan Artemia of the two developmental stages (0 and 19 day old after hatching) were investigated in the larboratory. The population growth of B. rotundiformis and one of the stage (nauplius or adult) of Artemia in mixed culture was compared with that of each single species culture. Culture period was 16 days. Every two days, the number of organisms in each species was counted and transferred to a fresh medium containing $7{\times}10^5$cells/ml of food Nannochloropsis oculata. Culture volume, temperature, salinity and photoperiod were set at 40ml, $25^{\circ}C.$, 22ppt and 24h all dark except to observation time, respectively. The rotifer population growth was greatly decreased by co-existence with Artemia. The coexisting Artemia suppressed the rotifer population growth due to it's high filtering speed for food (N. oculata). This study suggested that contamination by Artemia must be prevented for the stable rotifer production in the rotifer mass culture tank.

• Ocean and Polar Research
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• v.35 no.4
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• pp.299-312
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• 2013

This study analyzed the species composition and density of a macrobenthic community according to variations in the thermal discharge volumes of a nuclear power plant before, during, and after the shutdown of the nuclear power plant during two periods. In this study, 369 macrobenthic fauna species were collected, and their mean density was 1,712 ind. $m^{-2}$. The number of species and diversity of macrobenthic fauna decreased with distance from the thermal discharge area, regardless of whether the nuclear plant shutdown or not. Many macrobenthic taxa appeared near the thermal discharge area, but polychaetes species were more prominent in outer areas than at the discharge area. The density of macrobenthic fauna decreased with distance from the thermal discharge area during a plant shutdown in the fall of 2011, but increased, except at two sites, near the discharge area in the winter of 2012. Cluster analysis indicated that the spatial distribution of the macrobenthic community changed in areas near the nuclear power plant after a shutdown period; that is, the station group I, in areas near the nuclear power plant, became narrower after the shutdown, but it recovered to previously occupied areas after the nuclear power plant began operating again. Opportunistic species, such as the polychaetes Lumbrineris longifolia (= Scoletoma longifolia) and Mediomastus californiensis, which were present in high densities near thermal discharge areas, decreased after the shutdown but recovered after the plant re-opened. The number of species and diversity of the macrofauna and the density of dominant species showed a significant correlation with temperature, except in winter periods. The results of this study revealed that changes in the amount of thermal discharge before and after the shutdown of a nuclear power plant could exert an influence on the structure of macrobenthic community within the thermal discharge areas depending on the season.