• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.3
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• pp.10-20
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• 2019

Irregular rainfall caused by climate change, in combination with non-point pollution, can cause water systems worldwide to suffer from frequent eutrophication and algal blooms. This type of water pollution is more common in agricultural prone to water system inflow of non-point pollution. Therefore, in this study, the correlation between Unmanned Aerial Vehicle(UAV) multi-spectral images and total phosphorus, total nitrogen, and chlorophyll-a with indirect association of algal blooms, was analyzed to identify the usability of UAV image to identify water quality characteristics in agricultural streams. The analysis the vegetation index Normalized Differences Index (NDVI), the Normalized Differences Red Edge(NDRE), and the Chlorophyll Index Red Edge(CIRE) for the detection of multi-spectral images and algal blooms collected from the target regions Yang cheon and Hamyang Wicheon. The analysis of the correlation between image values and water quality analysis values for the water sampling points, total phosphorus at a significance level of 0.05 was correlated with the CIRE(0.66), and chlorophyll-a showed correlation with Blue(-0.67), Green(-0.66), NDVI(0.75), NDRE (0.67), CIRE(0.74). Total nitrogen was correlated with the Red(-0.64), Red edge (-0.64) and Near-Infrared Ray(NIR)(-0.72) wavelength at the significance level of 0.05. The results of this study confirmed a significant correlations between multi-spectral images collected through UAV and the factors responsible for water pollution, In the case of the vegetation index used for the detection of algal bloom, the possibility of identification of not only chlorophyll-a but also total phosphorus was confirmed. This data will be used as a meaningful data for counterplan such as selecting non-point pollution apprehensive area in agricultural area.

• Journal of Environmental Health Sciences
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• v.15 no.2
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• pp.11-23
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• 1989

This study was performed to investigate present water quality and pollution characteristics of them in the basin area of the Mankyung river near Chonju urban stream. In order to obtain the pollution characteristics of this investigation, the physio-chemical water analysis as temperature, pH, DO, BOD, Cd, Cu, Pb and Zn, and coliform group and their correlation analysis were determined from March to August 1988. The main results were summarized as follows 1. Each chemical constituent detected in three streams has the following variation range as pH(6.7-7.3), DO(1.3-8.9 mg/l), BOD(1.6-162.5mg/l) and water temperature was dominated by atmospheric temperature. 2. In three streams, concentration range of heavy metal was Cd N.D.-2.8 $\mu$g/l, Cu 1.1-10.2 $\mu$g/l, Pb 2.1-13.2 $\mu$g/l and Zn 25.6-62.2 $\mu$g/l, and was shown the order of Zn, Pb, Cu and Cd. 3. In the investigation on the bacteriological pollution-in the three streams. 1) The average number of general bacteria contaminated in the Chonju urban stream was $1.7 \times 10^{5}$ numbers/ml, which was higher than $2.6 \times 10^{2}$ numbers/ml, in the Gosan stream and 1.6 $\times$ 10 numbers/ml in the Mankyung river. 2) The average number of total coliform, fecal coliform and fecal streptococcus contaminated in the Chonju urban stream which was the highest polluted site than those of the other sampling sites were respectively $2.1 \times 10^{5}$, $2.1 \times 10^{5}$ and $9.6 \times 10^{4}$ MPN/100ml. 4. Correlation coefficient between GB and TC in the Chonju stream, Gosan stream and Mankyung river was respectively 0.99, 0.96 and 0.99, Correlation coefficient between TC and FC in Chonju stream, Gosan stream and Mankyung river was respectively 0.99, 0.97 and 0.99 and correlation coefficient between FC and TC was respectively 0.99, 0.91 and 0.99. This results mean positively dose relationship between them. 5. The occupied percentage of FC of TC in the Chonju stream, Gosan stream and Mankyung river was respectively 88.1%, 68.4% and 77.9% and the percentage of Tc of TS was respectively 43.5%, 31.6% and 41.4%. These .results was considered indicative of pollution derived from domestic wastes which had been contaminated by the feces of inhabitants and domestic animals.

• Journal of The Korean Society of Agricultural Engineers
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• v.52 no.3
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• pp.81-88
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• 2010

The purpose of this study is to analyze the spatial characteristics of Namgang-Dam watershed for a Total Maximum Daily Loads (TMDL). Three TMDL target sites, Gyeonghogang1, 2, Namgang-Dam2, are located within Namgang-Dam watershed. Under the current criterion for TMDLs, 3-year arithmetic mean BOD concentration of the target sites should not exceed the target concentration for 2 consecutive years. Two and three times of violation were observed for Gyenghogang2 and Namgang-Dam2 sites while no violation was found for Gyeonghogang1 site. However, no violation was found since 1999 for all three sites. Correlation between each 12 stations within the watershed were analyzed and cluster analysis was conducted to figure out the spatial characteristics of the watershed. Correlation coefficient between Gyonghogang1 and 2 was high (0.758) while the coefficients between lake station (Namgang-Dam2) and stream stations (Gyonghogang1 and 2) were very low. Dendrogram indicated that all of three Namgang-Dam stations were very close and Gyenghogang1, 2 stations were also close.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.4
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• pp.203-209
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• 1998

The quality of groundwater used for natural mineral water should be strictly regulated on international level by hydrogeology experts and officials because groundwater is greatly subjected to contaminations and its aquifer system may be easily destroyed by external reasons. A total of 18 natural mineral water plants exist in Precambrian metamorphic terrains of the Gyunggi massif and Yeungam massif. The g개undwater quality for the natural mineral water investigated in hydrochemical aspects shows that pH ranges from 6.85 to 8.02 with an average of 7.52. The electric conductivity (EC) and hardness average 134.1 $\mu$S/cm and 43.5, respectively, which are relatively low to the total average (151.4 $\mu$S/cm and 57.9). The contents of major cations and anions are in the order of $Ca^{2＋}$＞$Na^{＋}$＞Mg$^{2＋}$＞K$^{＋}$ and HCO$_3$$^{-}$ ＞SO$_4$$^{2－}$ ＞Cl$^{-}$ ＞F$^{-}$ , respectively. The dominant water types determined by Piper diagram are $Ca^{2＋}$－$Na^{＋}$－HCO$^{-}$ $_3$and $Ca^{2＋}$-HCO$^{-}$ $_3$, mainly due to the dissolution of plagioclase in the host rocks. Representative correlation coefficients between chemical species are $Ca^{2＋}$－HCO$^{-}$ $_3$(0.92), $Ca^{2＋}$－Cl$^{-}$ (0.63), $Na^{＋}$－F$^{-}$ (0.67), HCO$^{-}$ $_3$－Cl$^{-}$ (0.66), and $Na^{＋}$－HCO$^{-}$ $_3$(0.63). The determinative. coefficients between $Ca^{2＋}$ and HCO$^{-}$ $_3$, and (Ca$^{2＋}$＋$Na^{＋}$＋K$^{＋}$ and EC art highest among the elements. According to the saturation index, most chemical species are undersaturated with respect to major minerals, except for some silica phases. In viewpoint of phase equilibrium, the chemical evolution of the groundwater may continue to proceed with increasing pH because the groundwater is undersaturated with respect to feldspars.

• Journal of Korean Society on Water Environment
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• v.24 no.1
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• pp.69-77
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• 2008

This study was conducted to know the characteristics of agricultural non-point source pollutants runoff by rainfall events at the upper catchment of Goseong reservoir in Gonjy city, Chungnam Province. For this study, the monitoring sites of the research catchment were set nineteen during the research period (between June 2005 and October 2006). Average runoff coefficient were observed 0.51 in 2005, 0.71 in 2006, respectively. The correlation coefficient (r) between the rainfall and peak-flow was investigated 0.787. By rainfall events, the water quality of the sites were shown like this : BOD 0.555~9.60 mg/L, T-N 0.01~13.50 mg/L, T-P 0.002~2.952 mg/L, and SS N.D~820.0 mg/L. The strong rainfall intensity was the most important factor of the soil erosion. The gabs of the arithmetic mean concentrations and the flow weighted mean concentrations were observed as the followings : BOD 0.0~29.2%, T-N 0.1~11.4%, T-P 0.4~95.2%, and SS 1.7~57.0% in 2005, and BOD 1.0~11.9%, T-N 0.7~7.3%, T-P 9.9~36.5%, and SS 6.6~36.5% in 2006, respectively. The BOD pollution load was 2,117 kg (36% of the total BOD loading of survey periods) while, T-N was 3,209.0 kg (27.9% of the total T-N loading of survey periods), T-P was 136.4 kg (37.4% of the total T-P loading of survey periods) and SS was 72,733.8 kg (51.8% of the total SS loading of survey periods) in the year 2005. In case of 2006, BOD load was 1,321.7, T-N was 2,845.8, T-P was 42.9, and SS was 16,275.8 kg, respectively.

• Korean Journal of Ecology and Environment
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• v.35 no.4 s.100
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• pp.257-265
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• 2002

The current study was performed to elucidate the relationship between the anatoxin -a produced by cyanobacteria and aquatic environmental factors, Algal and water samples were collected from the Daechung Reservoir from June to November 2001. The physical factors of the water quality were measured in sifu, while the biological and chemical factors were examined in the laboratory. The concentrations of anatoxin-a in the algal and water samples were analyzed by HPLC using a fluorescence detector, and ranged from $0.61-8.68\;{\mu}g/g$ dw in the algal samples and $0.01-0.08\;{\mu}g/L$ in the water samples. The suggested maximum concentration of anatoxin-a for safe drinking water is $1\;{\mu}g/L$. The concentrations of anatoxin-a in the algal and water samples were highest in July. The relationships between tile aquatic environmental factors and the anatoxin-a concentration were also analyzed to identify the crucial elements for toxin production. The anatoxin-a concentrations in the algal samples exhibited a high correlation with nitrate, the TN/TP ratio, TDN (P<0.05), and TPN/TPP ratio (P<0.01), whereas the anatoxin-a concentrations in the water samples were highly related to the water temperature, conductivity (P<0.01) , pH, phycocyanin, and phycocyanin/chlorophyll a ratio (P<0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.6
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• pp.914-918
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• 2018

Objective: The relationship between water-holding capacity (WHC) and intermuscular fat (IMF) was studied in Japanese commercial pork. Methods: Longissimus muscles of pigs (n = 62), obtained from two meat packing plants, were analyzed for IMF content, moisture content, drip loss, cooking loss, and pH. Pairwise relationships among these traits were determined using correlation analyses. Results: IMF content was significantly correlated with moisture content (r = -0.88; p<0.01) and pH (r = 0.32; p<0.05), but not with drip loss (r = -0.23; p = 0.07) or cooking loss (r = -0.10; p = 0.42). In contrast, drip loss was significantly (and negatively) correlated with pH (r = -0.57; p<0.01). Conclusion: IMF content was not significantly correlated with WHC in pork, and so ultimately, we consider pH to be one of the most important factors influencing WHC in pork meat.

• Journal of Environmental Health Sciences
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• v.35 no.3
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• pp.162-168
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• 2009

The aim of this study is to investigate microbial sanitary condition of public baths in Seoul, Korea. A total of 28 water samples were collected from 14 different public baths and sudatoriums. The prevalence of fecal indicator microorganisms such as total coliform, fecal coliform, and Escherichia coli was characterized. In addition, bacteria in water was membrane filtered by 0.45um nitrocellulose membrane, and the filter was analyzed by both cultivation and PCR amplification of partial 16S rRNA gene. The levels of chlorine were measured for each of water samples. More than 40% of 14 collected water samples, the concentrations of total coliform bacteria exceeded the water quality for bath water guideline. There was no significant correlation between chlorine residue and the presence of total coliform. Various microorganisms including pathogenic microorganisms were identified from cultivation and subsequent analysis of 16s rRNA gene sequences. Our results suggest that appropriate hygiene practice and continuous monitoring is needed for reducing health risk associated with public bathhouses.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.6
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• pp.1220-1227
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• 2001

The condensation pressure drop fur refrigerant R-22 flowing in the plate and shell heat exchanger were investigated experimentally in this study. Two vertical counterflow channels were formed in the exchanger by three plates of commercial geometry with a corrugated trapezoid shape of a chevron angel of $45^{\circ}$. The condensing R-22 flowing down in one channel exchanges heat with the cold water flowing up in the other channel. The effects of the mean vapor quality, mass flux, average imposed heat flux and system pressure of R-22 on the pressure drop were explored in detail. The quality change of R-22 between the inlet and outlet of the refrigerant channel ranges from 0.03 to 0.05. The present data showed that pressure drop increases with the vapor quality. At a higher mass flux, pressure drop is higher for the entire range of the vapor quality. Also, a rise in the average imposed heat flux causes an slight increase in the Pressure drop. Finally, at a higher system pressure the pressure drop is found to be slightly lower. Correlation is also provided for the measured pressure drops in terms of the friction factor.

• Korean Journal of Plant Resources
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• v.11 no.1
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• pp.70-79
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• 1998

This study was conducted to understand the effects of weather and tapping date on yield and quality of lactree(Rhus verniciflua) sap yield showed a significant positive correlation with the minimum temperature of one day before sap collection at 1% level and with theminimum humidity of theday of sap collection at 5% level. However, the differences between the maximum and the minimum temperatures and humidities of the day of sap collection were negatively correlated with the sap yield at 5% level. Multiple regression analysis indicated that the minimum temperature of one day bofore sap collection and the minumum humidity of the day sap collection were important factors for increasing sap yield. The high sap yield of lactree by Japanese tapping method was recorded during mid-July and early August. Seasonal variation in lactree sap constituents was observed. The sap collected on 15th of August contained the highest urushiol content (68.3%) and the lowest water content resulting in high quality of lactree sap. By reversed-phase HPLC analysis, fove urushiol components were separated from each other depending on the number of doulbe bonds in the side-chain , and seaxonal variation of urushiol composition was noticed. The 3-C15 triene content fo the sap collected on 5th of July was the highest(77.56%) indicating the major component of urushiol which affects lactree sap quality.