• Journal of Environmental Health Sciences
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• v.3 no.1
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• pp.9-12
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• 1976

A study was performed to find out the fluoride contents in surface and ground waters from June, 1973 to July, 1974. Water samples were collected from 53 surface and ground water sources. The results are as follows: 1. Out of 53 samples, the ground water of Hwaengsung had the highest fluoride contents (1.6 mg/l) and 13 samples did not. have fluoride at all. 2. The waters from Yoju (ground), Chongnung (ground) Hwaengsung (ground) and Namyang (ground) had optimum fluoride level (0.6~1.7mg/l) for the prevention of dental caries. 3. The ground waters had more fluoride contents than surface waters and the waters of coastal areas had less fluoride contents than those of inland. 4. The waters of Kangwon province had the most fluoride contents (mean 0.57mg/l) and the waters of Cheju do had the least fluoride contents (mean 0.06 mg/l)

• Korean Journal of Agricultural Science
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• v.50 no.3
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• pp.507-512
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• 2023

The traditional oviposition ground for indoor breeding of Luciola lateralis is moss. This study was conducted to find the most suitable alternative oviposition ground that can maintain or increase the oviposition rate of L. lateralis while addressing the problems of larva collection time and larva loss that occur when moss is used. As alternative candidate oviposition ground comprising six colors of non-woven fabric and felt were used to measure the fecundity variation rate of L. lateralis with respect to the color and material of the oviposition ground. In addition, measure the fecundity variation rate of L. lateralis in moss, a traditional oviposition ground, was also measured and investigated for comparison. The investigation showed that the average number of eggs in the non-woven fabric group was higher than that in the felt group. The yellow non-woven fabric had an average number of eggs that was more than 100 times higher than of moss used as a traditional oviposition ground. In the space where the six color non-woven fabric were together, L. lateralis concentrated its oviposition on yellow. These results showed that yellow non-woven fabric can be sufficiently used for efficient indoor mass breeding of L. lateralis while addressing problems caused by moss, a traditional oviposition ground.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.888-892
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• 2000

Antimicrobial activity of Caesalpina sappan L. extract (CS extract) against 6 kinds of food spoilage and pathogenic organisms was studied. The growth of Listeria monocytogenes Brie 1, Escherichis coli ATCC 11775, Staphylococcus aureus ATCC 11775, and Pseudomonas fluorescens ATCC 11775 was inhibited about 4 to 5 $log_{10}$ cycle in Tryptic soy Broth(TSB) containing 1% CS extract. Bacillus subtilis KCTC 102 and Vibrio parahaemolyticus ACTT 17802 did not show apparent growth in the same medium. Effect of CS extract on preservation of ground meat was also investigated. The range of pH change was 5.0~5.2 in CS extract added ground meat, 5.2~6.0 in CS extract not added ground meat (control) during storage at 4$^{\circ}C$ for 30 days. Number of total bacteria after 15 days storage was $10^{6}$/g in CS extract added ground meat, 10$^3$/g in control. Redness of ground meats was improved significantly by addition of 1% CS extract during storage at 4$^{\circ}C$ for 30 days. The sensory quality of 1% CS extract added hamburger patty was similar to that of the control in taste, flavor, and overall acceptability.

• Journal of Environmental Health Sciences
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• v.18 no.1
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• pp.34-38
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• 1992

This study was carried out to investigate silicate-silicious in spring water and ground water. Samples were collected from 23 Stations of spring water and 2 Stations of ground water from August 1985 to July 1990 in Pusan area. Range and mean value of silicate-silicious of spring water and ground water were lower 2.12~22.70mg/l, 8.78mg/l, 13.90~19.05mg/l, 16.23mg/l than the criterion for drinking water as 50rng/l. The concentration of silicate-silicious had a great influence on precipitation, therefore it in summer was higher than in winter. The estimated regression line between chloride ion(x) and silicate-silicious(y) of the sampled water was y=19.366-0.604x(r=-0.7111).

• Journal of the Earthquake Engineering Society of Korea
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• v.24 no.6
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• pp.277-283
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• 2020

In order to improve the ground-motion prediction equation, which is an important factor in seismic hazard assessment, it is essential to obtain good quality seismic data for a region. The Korean Peninsula has an environment in which it is difficult to obtain strong ground motion data. However, because digital seismic observation networks have become denser since the mid-2000s and moderate earthquake events such as the Odaesan earthquake (Jan. 20, 2007, M_L 4.8), the 9.12 Gyeongju earthquake (Sep. 12, 2016, M_L 5.8), and the Pohang earthquake (Nov. 15, 2017, M_L 5.4) have occurred, some good empirical data on ground motion could have been accumulated. In this study, we tried to build a ground motion database that can be used for the development of the ground motion attenuation equation by collecting seismic data accumulated since the 2000s. The database was constructed in the form of a flat file with RotD50 peak ground acceleration, 5% damped pseudo-spectral acceleration, and meta information related to hypocenter, path, site, and data processing. The seismic data used were the velocity and accelerogram data for events over M_L 3.0 observed between 2003 and 2019 by the Korean National Seismic Network administered by the Korea Meteorological Administration. The final flat file contains 10,795 ground motion data items for 141 events. Although this study focuses mainly on organizing earthquake ground-motion waveforms and their data processing, it is thought that the study will contribute to reducing uncertainty in evaluating seismic hazard in the Korean Peninsula if detailed information about epicenters and stations is supplemented in the future.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.303-306
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• 2003

This survey was carried out to investigate the chemical characteristics of ground water for livestock purpose and to estimate the influence of ground water quality by livestock farming. Water samples were collected three times in 2000, and analyzed for theirs chemical compositions using Korean Standard Methods for Water Quality. The EC of ground water was from 0.214 to 0.474 dS/m. $NO_3-N$ contamination range was from 3.56 to 11.81. The $SO_4{^{2-}}$ was $4.31{\sim}69.37mg/L$ and CI was $12.75{\sim}41.46mg/L$. The data of ground water quality indicated suitable quality for livestock. Also, the concentration of heavy metals in the sample could not make damage to the animals. The $NO_3-N$ concentration of the water by times are as follows: October (8.19 mg/L) > July (7.65 mg/L) > April (4.04 mg/L) with no significant differences during the livestock farming period. The average quality of groundwater for livestock is good for its purpose, and it was showed there was few influence by livestock farming.

• Journal of environmental and Sanitary engineering
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• v.12 no.2
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• pp.43-49
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• 1997

Iron and manganese problems in ground water affect far more water systems than almost any other water quality concern. The purpose of this study is to find the optimum condition of ozonation for the removal of dissolved iron, manganese and other organics in the polluted ground water. We proposed 4mg/l, 8mg/l as optimum ozone dose for the removal of $Fe^{2+},{\;}Mn^{2+}$, respectively. The removal efficiencies of $COD_{Mn}$ and $COD_{Cr}$ in ozone dose of 2mg/l - 6mg/l were about 40-50%. The removal efficiency of $NH_{3}-N$ was about 30-40% at pH8.5. In conclusion, it needs further systematic study and research concerned to treatability of $Fe^{2+},{\;}Mn^{2+}$ and biodegradability of organic compounds using Ozonation followed by biological filtration process in ground water treatment train.

• Bulletin of the Korean Chemical Society
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• v.25 no.6
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• pp.806-808
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• 2004

A gas chromatography/mass spectrometric assay method has been developed for the simultaneous determination of icing inhibitors, ethylene glycol monomethyl ether and diethylene glycol monomethyl ether in ground water contaminated with JP-8. Ethylene glycol monobutyl ether and ethylene glycol monoethyl ether were used as the internal standard and surrogate, respectively. 100 mL of ground water was extracted twice with 20 mL of methylene chloride. The extract was concentrated to dryness, dissolved with 100 ${\mu}$L of methanol and analyzed by GC-MS (SIM). The use of an Innowax column gave the peaks good chromatographic properties, and the extraction of these compounds from samples gave recoveries of about 50% with small variations. The method detection limits of the target compounds were in a range of 0.5-0.8 ng/mL in ground water.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.05a
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• pp.92-95
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• 2000

A mixed bacterial culture capable of mineralizing methyl tort-butyl ether (MTBE), other fuel oxygenates ethers, tertiary carbon alcohols, benzene and toluene was used to inoculate batch reactor and sequence batch reactor (SBR) to treat gasoline contaminated ground water containing about 60 mg/L MTBE, 5 mg/L benzene, 5 mg/L toluene, and low concentrations of several other aromatic and aliphatic hydrocarbons. Respirometery studies showed that MTBE degrading mixed culture could treat MTBE contaminated ground water with addition of nitrogen and phosphate. SBR was operated to demonstrate the feasibility of using suspended growth activated system for the treatment of ground water and to confirm that the respirometry derived kinetics and stoichiometric coefficients were useful for predicting reactor performance. Theoretical performance of the reactor was predicted using mathematical models calibrated with biokinetic parameters derived from respirometry studies.

• Preventive Nutrition and Food Science
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• v.8 no.2
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• pp.196-199
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• 2003

We investigated the antagonistic effects of two lactococcal bacteriocins, nisin or lacticin NK24, on the growth and the survival of Listeria monocytogenes in vacuum or modified atmosphere-packaged ground beef, Ground beef was inoculated with approximately 3 log colony-forming units (CFU) of L. monocytogenes ATCC 15313 culture per gram of ground beef. Inoculated samples were blended with/without 100 AU/g nisin or lacticin NK24, and subsequently vacuum or modified atmosphere packed at 4$^{\circ}C$. Listeria in the bacteriocin-treated and control samples was subsequently isolated from both vacuum and modified atmosphere packs and enumerated as CFU on Listeria Isolation Agar medium. Microbial counts in ground beef treated with bacteriocin declined steadily, while those of non-treated beef samples increased steadily. The results obtained demonstrate that nisin inhibits the growth of L. monocytogenes more effectively than lacticin NK24 at 100 AU/g. The use of lactococcal bacteriocins, such as nisin or lacticin NK24, in vacuum or modified atmosphere packaging offers a promising approach for eliminating or reducing the risk of L monocytogenes contamination in ground beef.