• Korean Journal of Ichthyology
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• v.2 no.1
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• pp.63-76
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• 1990

Studies on the microdistribution, distributional aspect and affinity of Korean endemic species, SHIRl, Coreoleueiseus splendidus in th southern half of the Korean peninsula were carried out from May, 1966 to November, 1989. This species was found in 14 independent rivers and streamlets of the south Korea ; Yimjin R., Han R., Kum R., Ungchun S., Mangyung S., Dongjin R., Somjin R., Kwangyang East S., Sachun S., Gonyang S., Nakdong R., Samchukosip S., Samhwa S. of Namhae Island and Guchun S. of Geojae Islands, and were not found from Youngsan R., Ansung S. and Sabgyo S. This species was not common and independent comprising less than 25% of the total fish population in all habiting sites. Distributional zone was in the middle or upper streaches of main streams and tributaries. The average slope of distributional zone was 2.6, minimum slope was 0.29 and maximum slope was 5.56. Thirty-three species were found to occur along with this fish and 10 species of them occurred with more than 50% frequency. They were; 20 sp. of Cyprinidae, 5 sp. of Cobitidae, 1 sp. of Salmonidae, 1 sp. of Bagfridae, 1 sp. of Siluridae, 2 sp. of Amblycipitidae, of Serranidae, and 1 sp. of Eleotridae. Some species of fish appeared to have the same ecological position even though they have different distributional zones. These species were as follows; Acheilognathus signifer and A. limbata, Micriophsogobio koreensis and M. yaluensis in Cyprinidae, Cobitis koreensis, C. longicorpus, C. rotundicaudata in Cobitidae, Liobagrus andersoni and L. mediadiposalis in Amblycipitidae.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4717-4724
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• 2012

This study is to examine the relation between Korean fermented food and discoloration on teeth, which have undergone profession tooth whitening. The color change of natural tooth, which has undergone professional tooth whitening, is objectively measured by dental colorimeter after being immersed in Korean fermented food for certain period. The tooth specimens used in this study are 30 pieces and measured 30 times per one tooth, 900 times totally by dental colorimeter ShadeEye NCC$^{(R)}$ Dental Chroma Meter. As a result of analyzing the collected data by using PASW(statistical package) 18.0, the significant difference is found (p<0.001) in lightness and yellowness before and after of professional tooth whitening. The lightness and yellowness after immersion is changed (p<0.001) according to time. As a result of examining the degree of discoloration based on type of fluids, the similar difference is indicated (p=0.001, p<0.001 1,2 and 3 weeks after getting professional tooth whitening. As a result, Korean traditional fermented food influences on discoloration on bleached tooth depended on the duration of immersion and the type of fluids. However, this study failed to represent internal oral condition accurately therefore the results of this study could be altered by the internal oral condition, frequency of consumption of food, and the management oral hygiene.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.32 no.5
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• pp.322-330
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• 2020

Modeling for outliers in time series was carried out using the MSL and extreme high, low tide levels (EHL, HLL) data set in the Busan and Mokpo stations. The time-series model is seasonal ARIMA model including the components of the AO (additive outliers) and LS (level shift). The optimal model was selected based on the AIC value and the model parameters were estimated using the 'tso' function (in 'tsoutliers' package of R). The main results by the model application, i.e.. outliers and level shift detections, are as follows. (1) The two AO are detected in the Busan monthly EHL data and the AO magnitudes were estimated to 65.5 cm (by typhoon MAEMI) and 29.5 cm (by typhoon SANBA), respectively. (2) The one level shift in 1983 is detected in Mokpo monthly MSL data, and the LS magnitude was estimated to 21.2 cm by the Youngsan River tidal estuary barrier construction. On the other hand, the RMS errors are computed about 1.95 cm (MSL), 5.11 cm (EHL), and 6.50 cm (ELL) in Busan station, and about 2.10 cm (MSL), 11.80 cm (EHL), and 9.14 cm (ELL) in Mokpo station, respectively.

• Korean Journal of Ecology and Environment
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• v.40 no.1
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• pp.82-92
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• 2007

In 2003, we evaluated biological water quality at twelve sites of Youngsan River using community analysis, fish compositions, and the Index of Biological Integrity (IBI). Of the twelve, four sites were the controls, which have no point sources in the upstream and the remaining eight sites were the impacted sites, which are influenced by wastewater treatment plant (WTP) and agro-industrial complex. Model values of the IBI, based on 12 sites data, averaged 28 (n=12, range: $18{\sim}44$), indicating fair poor condition according to the criteria of US EP A (1993). In the mean time, mean IBI in the control sites (S3, S5, S6, S11) was 42 (n=4, range: $38{\sim}44$), indicating a good condition, whereas mean IBI in the impacted sites was 21, indicating a poor condition. Mean IBI value in the control, thus, was greater by 2 fold than that in the WTP sites. The spatial pattern of IBI values was similar to the patterns of species diversity index and species richness index, except for Site 11, which was 1st order stream. Similarity analysis indicated that three groups were divided at the similarity level of 80%. One group was the streams influenced by wastewater and the other two groups were the pristine streams as the control, indicating that the stream health conditions are directly influenced by presence or absence of the point sources. Also, Pearson's correlation analysis showed that IBI values had negative correlation (r=0.899, p<0.001) with relative abundance of tolerance species, and had positive relation (r=0.890, p<0.001) with sensitive species. Overall, outcomes suggest that the point sources of the WTP might impact the species composition and ecological health, resulting in degradation of biological water quality.

• Korean Journal of Ecology and Environment
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• v.38 no.4 s.114
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• pp.445-453
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• 2005

Relative importance between bottom-up and top-down controls on phytoplankton dynamics was investigated in the Juam Reservoir, Chonnam based on the results from statistical analyses including regression and artificial neural network (ANN) modeling. Effects of nutrients on size-structured phytoplankton dynamics were explored by simple linear regression analysis and relative importance between bottom-up and top-down controls was estimated based on results from the artificial neural network analyses. Although there is a limitation in determining direct grazing effects since chlorophyll a : pheopigments ratios, indirect index for grazing activity rather than grazing rates or herbivores biomass were used, the results from regression analysis showed that nutrients especially orthophosphates were positively correlated with the phytoplankton biomass and chlorophyll a : pheopigments ratios were also positively correlated with the phytoplankton biomass at lower coefficient of determination ($r^2$) compared to orthophosphates. The simulation results from ANN suggested that the bottom-up mechanisms including water temperature and availability of nutrients, especially orthophosphates were more important than top-down mechanisms such as grazing in the phytoplankton dynamics.

• Korean journal of communication and information
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• v.60
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• pp.5-27
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• 2012

The purpose of this study is to explore the journalist Song Kun-Ho's ideas of Korean Journalism. The journalist Song Kun-Ho was born in 1926 and passed away in 2001. He became a reporter in 1953 when he was a student at department of law of Seoul National University. He has worked for several media and resigned the executive editor at the Dong Ah Ilbo in 1975. At that time, while many reporters of the Dong Ah Ilbo struggled for the freedom of the press, he tried to protect reporters and independence of media. After his resignation of the executive editor, he wrote many columns and several books for Korean nationalism and the democracy of journalism. Instead of working for the authoritarian military regime, he chose a lonely and rough life as an intellectual journalist in action. Finally, he, as a president, established the Hankyoreh daily newspaper which was funded by tens of thousands citizens. He passed away in 2001. His ideas of Korean journalism are nationalism, democracy, and independency. These ideas are very important to restore democratic journalism which has been at risk during the Lee Myung-bak administration.

• Journal of dental hygiene science
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• v.16 no.3
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• pp.235-241
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• 2016

This study was conducted to provide basic understanding regarding possible enamel erosion by three kinds of fist-aid antipyretic and analgesic medicines over a period of time, with comparison and analysis of the resulting deciduous teeth surface and microhardness changes. The analysis was performed using energy dispersive X-ray spectroscopy (EDX) and scanning electron microscope (SEM) to examine the surface erosion and changes. The Kruskal-Wallis test show differences in surface erosion and changes after 3, 5 and 8 days of treatment as well as before and after the treatment in each group. According to the results, there was no significant difference in the early deciduous teeth enamel surface microhardness (p>0.01). However there were signigicant changes after 3, 5, and 8 days (p<0.01). Calcim (Ca) and phosphorous (P) analysis using EDX showed significant differences in the enamel characteristics according to each tissue area after 8 days (p<0.05), but there was no significant difference in any of the areas for P content (p>0.05). In the surface observation with the SEM treatment with Children's Tylenol$^{(R)}$ tablet, which has the lowest pH, looked the roughest, followed by Brufen syrup for children and Children's Tylenol$^{(R)}$ suspension. Based on these results, it should be considered that antipyretic and analgesic medicines for children, which have lower pH values, may cause tooth erosion. Hence, it is necessary to give special attention to oral hygiene in young children or infants by brushing their teeth after such drugs are administered.