• Korean Journal of Environmental Agriculture
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• v.42 no.2
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• pp.139-151
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• 2023

Sulfonylurea herbicides are widely used in agriculture because they have a long residual period and high selectivity. An analytical method was developed using QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) technique for simultaneous determination of sulfonylurea herbicide residues in agricultural products by liquid chromatography tandem mass spectrometry and for establishment MRL (Maximum Residue Limit) of those herbicides in Korea. Extraction was performed using acetonitrile containing 0.1% formic acid with MgSO₄ (anhydrous magnesium sulfate) and NaCl (sodium chloride) and the extract was cleaned up using MgSO₄ and C₁₈ (octadecyl). The matrix-matched calibration curves were composed of 7 concentration levels from 0.001 to 0.25 mg/kg and their coefficients of determination (R²) exceeded 0.99. The recoveries of three spiking levels (LOQ, 10LOQ, 50LOQ, n=5) were in the range of 71.7-114.9% with relative standard deviations of less than 20.0% for all the five agriculture products. All validation values met criteria of the European Union SANTE/11312/2021 guidelines and Food and Drug Safety Evaluation guidelines. Therefore, the proposed analytical method was accurate, effective, and sensitive for sulfonylurea herbicide residues determination in agricultural commodities.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.384-389
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• 2010

Outbreak of contagious diseases to livestock animals is becoming prevalent worldwide and consequently, tremendous numbers of the infected or culled stocks are buried on the ground as the most common disposal method. The buried animals can generate a wide range of detrimental components such as leachate, nutrient salts, and pathogenic bacteria, consequently contaminating the surround environment. This implies that regular investigations are required to monitor any possible detrimental environmental aspect occurred around burial sites. Therefore, the current study was conducted to investigate whether the soil and groundwater nearby the burial sites had been contaminated by the substances originated from the burial sites, which can be applied for the establishment of the ideal burial site construction design and post management scheme. For this, two different burial sites located in Cheonan and Pyeongtaek were selected. Cheonan and Pyeongtaek sites were constructed in 2004 and 2008, respectively and both contained dead poultry infected by avian influenza (AI). Soil and groundwater samples were collected around the sites followed by determination of the nutrient concentrations and bacteria (Salmonella, Camphylobacter, and Bacillus) existence in both soil and groundwater. Some of the soil samples showed higher EC, $NH_4$-N, $NO_3$-N concentration compared to those of the background (control) soils. Also the concentration of $NH_4$-N in some of the groundwater samples appeared to exceed the USEPA guideline value for drinking water (10 mg $L^{-1}$). These results indicated that the soil and groundwater were influenced by the burial site originated nutrients. In the soil, Bacillus was isolated in most soil samples while there were no detections of Salmonella and Camplylobacter. Due to the Bacillus existing mainly as a spore in the soils, it was considered that the frequent detection of Bacillus in the soil samples was attributed to the nutrients originated from the burial sites.

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.1
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• pp.67-76
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• 2010

The purpose of this study was to suggest the growth characteristics, seasonal anthesis distribution and botanical composition of wildflower pasture. The experimental wildflower were 34 species (1 turfgrass species, 4 native wildflower species and 29 introduced wildflower species). The experiment were administered in the Chungnam National University experimental field from March, 2008 to December, 2009 and the result is as follows: the wildflower length were within the range of 8-60 cm and their up-and-down space arrangement quite good. They bloomed into several colors of nine but one or three of nine colors were biased during August, September, and October. Their anthesis was biased toward May and June, and their seasonal distribution and permanence maintenance were too difficult from August and moreover two years later (2009) because of the decrease of the botanical distribution of annual wildflower after winter, the color, seasonal distribution, and permanence of wildflower became a problem. The botanical composition of wildflower, turf grass, and weeds came to 24%, 62%, and 14% each one year later (2008) and two years later (2009) 16%, 69%, and 15% each. Being grounded upon this result, in case of wildflower pasture of spring seeding, it is more important to maintain the color, seasonal distribution, and permanence of wildflower two years later than in the establishment year.

• The Journal of the Korea Contents Association
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• v.8 no.7
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• pp.208-215
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• 2008

Sport industry creates value-added by production and distribution of product or service related with sports or sports. Because this industry shows promise in becoming a major industry area, the government is making an effort to bring up or develop it. The financing to firms of sport industry area(sporting goods industry, sport facility industry, sport service industry) with low interest rate and long-term repayment period on the basis of sports promotion fund is excellent scheme to promote sport industry. Nevertheless, Because many people indicate operational inefficiency of it, it is necessary to check operational efficiency through investigation for loan system of sports promotion fund. The purposes of this paper are to present some directions for the improvement of efficiency by the analysis to public loan system using funds of other government organization and to the current status of loan system of sports promotion fund. The result of this study are as follows. First, we propose enlargement of loan size and range. Second, it is necessary to use mortgages loan to technology in case of sporting goods industry and sport service industry. Third, we suggest the mitigation of loan disproportion and flexible application among loam amount of sport industry areas. Fourth, we suggest the construction of loan practical committee. Finally we propose the establishment of selection criteria to firms and ex-post evaluation system related with loan system of sports promotion fund.

• Journal of Environmental Science International
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• v.16 no.3
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• pp.357-367
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• 2007

Recently, eutrophication or lake and reservoir has become serious problem to man who want use that water for several purpose. In order to solve the eutrophication problem, the trophic state of that eutrophic lake and reservoir should be measured properly. For the purpose of this, various method to indicate the trophic state of lake and reservoir was developed by many researchers. This research was conducted to evaluate characteristics and eutrophication of water qualitymfor small scale reservoir in Kunsan. On-site investigation to 5 reservoirs and laboratory experiment were carried out during four seasons from November, 2003 to July, 2004. Twelve items measured field ana a laboratory. Measured data was analyzed to quantitative method by multivariate approach and eutrophication index. The result is summarized as following. 1) Showing the characteristics of water quality for reservoir in Kunsan, Okgu reservoir and Oknua reservoir was exceeded 4 grades of agricultural water standard in TP, TN and COD. This means that eutrophication was gone much, therefore, water-purity control of reservoir need. While, Mije reservoir that is used to Kunsan citizens' recreation was good in water quality. But, water quality exceeded 4 grades of agricultural Dater standard sometimes. 2) As a results of correlation analysis between variables of water qualify, Interrelation between variables which is connected with eutrophication was expressed good relationship as above 6.000 in correlation coefficients. The correlation coefficient(r) between COD and chlorophyll-a, total phosphorus and chlorophyll-a, total nitrogen and chlorophyll-a were 0.750, 0.720 and 0.600 respectively. Therefore, Change of water quality can grasp according to eutrophication progress degree. 3) If do evaluate to eutrophication by quantitative method which is proposed by OECD, US-EPA and Forsberg & Ryding, in the case of chlorophyll a, Okgu, Oknua and Daewi reservoir was eutrophic state and Mije and Geumgul reservoir was mesotrophic state. But, estimation by TN and TP showed highly eutrophic state (hypereutrophic) in all reservoirs. 4) If do evaluate by eutrophication index which is Carlson's TSI, revised carlson TSI and Walker's index, in the case of chlorophyll a, TSI values of Okgu, Oknua and Daewi reservoir is eutrophic state more than 50 and Mije and Geumgul reservoir was mesotrophic state as range of $40{\sim}50$ in TSI value. But, in the case of TP as nutrients, all reservoirs showed highly eutrophic state which was exceed to 70 in TSI value. According to above results, the water quality for small scale reservoirs in Kunsan is progressing by trophic state. therefore, for continuous use as agriculture water, we had better do establishment of management plan about water quality.

• Korean Journal of Breeding Science
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• v.41 no.1
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• pp.25-31
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• 2009

This study was conducted in order to breed Japonica salt tolerant rice and select salinity tolerant lines by establishing reliable and practical method of screening voluminous materials. Salinized nutrient solution by adding NaCl was effective compared with the salinized nutrient solution by adding 0.3%, 0.6% and 0.7% of diluted sea water. There was no different visual score of salinity injury between salinization using tap water and distilled water. Seedling salinity tolerant lines between region and order by year were showed very stable and reproducible results, 3~4.2 of visual score at Gyehwado-substation and International Rice Research Institute (IRRI, Philippines) in 2002, 2003 and 2004. Heading date of 6 selected seedling salt tolerant lines showed a range of 16. Aug.~21. Aug. and delayed 2~6 days than that of Donjinbyeo. Percentage of ripened grain and yield of milled rice in 6 lines was lower, 52.2~14.7% and 50~5%, respectively than those of Donjinbyeo.

• Korean Journal of Heritage: History & Science
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• v.54 no.3
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• pp.192-203
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• 2021

This paper investigates the process of change in the meaning of the term gongye (工藝) (nowadays it means craft) during Korea's transition to the modern era. The Annals of the Joseon Dynasty (朝鮮王朝實錄) will serve as the basis for the examination of pre-modern usage, and the Korea-United States Treaty of 1882 for the changes that occurred between the translation from Chinese and from Japanese following the opening of the port . After the port opened, the meaning of gongye, which once broadly referred to the wide range of work of people from different fields, was narrowed down to singularly represent the manufacturing industry. Following the example of Japan, the first East Asian country to succeed in modernization, this new meaning of gongye was generally used in the context of embracing Western culture and creating industry. As industrialization emerged as a national mission, and new terminology was needed to express these new concepts, the Chinese characters used by the Japanese to translate Western concepts were directly imported and used without making any changes. Gongye was similar in meaning to gongeop (工業) (nowadays it means industry) at the time, and the two terms were used interchangeably. However, following the Japanese annexation of Korea, the cultural administration of the Governor-General imbued the term with artistic concepts, and gongye was differentiated from gongeop, As such, examining the establishment of terminology and concepts can be helpful for understanding the contradictions and problems of the Korean crafts scene, which were derived from a period in the past called the modern era.

• Journal of the Korean Institute of Gas
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• v.21 no.4
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• pp.84-91
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• 2017

Recent years have witnessed the increased usage of flammable metals, such as aluminum or magnesium, in wide range of high-tech industries. These metals are indispensable for the improvement of physical properties of materials as well as the design capability of the final product. During the process, unwanted metal dusts could be released to the environment. This can lead to an occupational health and safety issues. Due to their flammable nature, more serious problem of an explosion can happen in extreme cases. The explosion is the combustion of tiny solid particles and vapor mixture, caused by pyrolysis. This complex composition makes engineering analysis more difficult, compared to simple gas explosions or vapor cloud combustions. The study was conducted to assess this light metal dust explosion in an effort to provide the bases for a risk assessment. Dust explosion characteristics of each material was carefully evaluated and an appropriate analysis tool was developed. A comprehensive database was also constructed and utilized for the calibration of the developed response model and the verification for its accuracy. Subsequently, guidelines were provided to prevent dust explosions that could occur in top-notch industrial processes.

• Journal of Food Hygiene and Safety
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• v.15 no.4
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• pp.315-323
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• 2000

Serious consequences can arise from lack of hygiene in mass catering. Microbiological testing is of value in determining hazards for developing a HACCP plan, and in demonstrating to food handlers the reality of the microbial risk. This studies was performed to describe the overall hygiene of cooking utensils and equipments, employees, and environment in mass catering establishments. Generally, hygienic conditions of cutting board and sanitized dish cloth were better than those of other cooking utensils such as knife, sieve, and peeler. It was found that the cross-contamination of knife might be caused by the use of contaminated sanitizing solution. It was observed that there was considerable variation (10$^1$~10$^{5}$ CFU) of the number of general bacteria for employee's hands. The number of general bacteria were influenced from establishment, employee, and the period of analysis. The number of Coliform group for employee's hands was in the range of 10$^2$~10$^4$CFU only at the first analysis. Total aerial bacteria in working area of mass catering establishments was below 7 CFU/Plate and aerial Staphylococcus sp. was not detected at all except one spot.

• Journal of Food Hygiene and Safety
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• v.32 no.5
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• pp.404-410
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• 2017

An analytical method for determination of propylene glycol alginate (PGA) in food products was developed by HPLC-size-exclusion chromatography. The GF-7M HQ column and LT-ELSD detector were determined by considering the instrumental analysis conditions for PGA analysis. The pretreatment method for the analysis of PGA was suitable for 3 hr extraction at $20^{\circ}C$ and 150 rpm according to the extraction temperature. Linearity ($R^2$) for the analysis of PGA was 0.9873 at calibration curve range of 300, 500, 700, 1,000, and 1,500 mg/kg (5 points). The limit of detection and limit of quantification of PGA on HPLC system was 171.43 and 519.50 mg/kg, respectively. The accuracy and coefficient of variation obtained by size-exclusion chromatography were 86.1~110.4% and 4.1~13.5%, respectively. By applying the HPLC-size-exclusion chromatography system, it was possible to analyze the contents of PGA in 134 different types of food products.