• Journal of agricultural medicine and community health
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• v.30 no.1
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• pp.39-50
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• 2005

Objectives: This investigation was carried out to explore the source and the mode of transmission of the diarrhea outbreak in Seongju-gun, Gyeongbuk, 2004 Methods: The authors conducted a questionnaire survey among the 275 persons (students, staff members and cooks) who ingested the possibly contaminated foods. We also investigated the drinking water and the dining facility, and we reviewed the process of cooking the salad, which was the presumed cause of the Enteropathogenic Escherichia coli(EPEC) diarrhea. The confirmed EPEC diarrheal case was defined as culture positive for EPEC, and the suspicious case was defined as diarrheal case with symptoms more than one of fever, vomiting and tenesmus. Results: The attack rate of EPEC diarrhea was 36.7%, and there were 8 confirmed cases. The possibility of the drinking being a source of the infection was very low, for chlorine was detected in all the drinking water via reviewing the past records and using a portable detector. The foods that were significantly associated with diarrhea were found. The relative risk (RR) for the lunch served Jul 7 was 4.12 (95% CI: 1.39-12.20). Among the non-boiled foods that were finally served, the RR for the salad was 1.66 (95% CI: 1.07-2.57). The cause of this outbreak was presumed to be the contaminated foods that were prepared by cooks using rubber glove with holes, and especially the salad and foods that were served sans boiling on Jul 7. Conclusions: Though this EPEC infection was not so clinically important, if a larger outbreak occurred, it might severely affect the public health. It is recommended to develop the more safe methods for cooking foods, and to strengthen the sanitary processing foods.

• Journal of agricultural medicine and community health
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• v.28 no.1
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• pp.79-92
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• 2003

Objectives: To investigate the reinfection rate of Helicobacter pylori and the factors related to reinfection of H. pylori, 86 persons were examined in April 2000 after 1 year follow-up period and 77 persons were examined in October 2001 after two and a half-year follow-up period in Gyeongju-si, Gyeongsangbuk-do, Korea. Methods: The subjects were confirmed as H. pylori negative by urea breath test(UBT), and asked to answer the questionnaire regarding demographic characteristics, dyspepsia symptoms, health-related behaviors and family history. Results: The reinfection rate on the first year of the eradication of H. pylori was 15.6%, when the 77 subjects have finished follow-up observation for one year. In the urea breath test performed after two and a half year, 13 out of 77 were positive, with the reinfection rate of 16.9%. Age, sex, socio-economical status, educational level and family history were not associated with the reinfection, while there was significant association between the reinfection and postprandial fullness and epigastric bloating in subjective dyspepsia that the subjects who were determined to be negative in the urea breath test for the following year. The treatment compliance and drinking were significant variables in univariate analysis. Meanwhile, the cases in which the dyspepsia symptom scores for the recent year were 2 to 3 points served as the only statistically significant variable in multiple logistic regression analysis, with the odds ratio of 4.5. The cases in which salt intake during meals was exceeded were 8.7 in the odds ratio, but statistically insignificant. Conclusions: Conclusively, the first-year reinfection rate was 15.6%, and the second-year reinfection rate was 16.9%. Thecomplaints of subjective dyspeptic symptoms and the treatment compliance, as the basis for predicting the H. pylori reinfection in communities, can be used as the basis to screen the subjects for follow-up examination to find out H. pylori infection.

• Clean Technology
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• v.24 no.1
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• pp.77-84
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• 2018

In this study, $Li_4Ti_5O_{12}$ anode materials for lithium ion battery were synthesized by dry ball-mill method. Polyvinyl chloride (PVC) as a carbon source was added to improve electrochemical properties. When the PVC was added after $Li_4Ti_5O_{12}$ formation, the spinel structure was well synthesized and it was confirmed by X-ray diffraction (XRD) experiments. When the carbon material was added before the synthesis and the heat treatment was performed, it was confirmed that a material having a different crystal structure was synthesized even when a small amount of carbon material was added. In the case of $Li_4Ti_5O_{12}$ without the carbon material, the electrical conductivity value was about $10{\mu}S\;m^{-1}$, which was very small and similar to that of the nonconductor. As the carbon was added, the electrical conductivity was greatly improved and increased up to 10,000 times. Electrochemical impedance spectroscopy (EIS) analysis showed that the size of semicircle corresponding to the resistance decreased with the carbon addition. This indicates that the resistance inside the electrode is reduced. According to the Cyclic voltammetry (CV) analysis, the potential difference between the oxidation peak and the reduction peak was reduced with carbon addition. This means that the rate of lithium ion insertion and deinsertion was increased. $Li_4Ti_5O_{12}$ with 9.5 wt% PVC added sample showed the best properties in rate capabilities of $180mA\;h\;g^{-1}$ at 0.2 C-rate, $165mA\;h\;g^{-1}$ at 0.5 C-rate, and $95.8mA\;h\;g^{-1}$ at 5 C-rate.

• Management & Information Systems Review
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• v.33 no.4
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• pp.1-19
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• 2014

This Study focuses on the university students' job attitude and cost of employment preparation. Nowadays, many university and college students spend a big money improving their employment preparation such as studying on foreign language, getting various kinds of certificates and tooth correction, clothing etc. for employment interview. This study investigated the cost of employment preparation and Job attitude of the 484 students of universities and colleges, the analysis of the collected data was conducted with SPSS 12.0 program by using frequency analysis, factor analysis, reliability assessment, correlation test, t-test, one way ANOVA. The university students paid more costs of employment preparation such as a language training abroad, a private training, and clothing than the college students. Also, Allied social science students paid more costs of the language training abroad, and clothing than allied computer science and allied design students. The female students paid more money than male students for tooth correction. The costs of language training abroad, private training and clothing are affected the students' socioeconomic background of a home. Regarding the job attitude of students, the university students are feeling more positive than the college students of the employment efficacy and cognition of the education environment. As result, the differences in the cost of employment preparation by the university type, faculty major course, their sex, and socioeconomic background of a home. The student's employment-efficacy and cognition of the education environment are also differences between the university and the college students. So, to improve the job attitude, developing their ability for employment preparation, educational programs should be arranged in school and continuous researches are needed.

• Asian Journal of Turfgrass Science
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• v.9 no.4
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• pp.293-316
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• 1995

Nitrogen fertilization and cutting practice were studied on turfgrasses and cover plants to investigate the possibility of maintaining green color during the growing season. Research also involved the effect of the nitrogen on a few morphological characteristics of leaf performance elements which might give an information to coloration and life-span of turf leaves. Treatments in the first experiment undertaken on pot included one N level: 350kgN /ha applied as compound fertilizer in split applications of one-half in mid-May and the rest both in late June and August, and four spring-summer cuts: late May, late June, late July and late August. The soil filled in pot a moderately well-drained sandy loam. In the second experiment(field observation) leaf length and width, inflorescence and flowering, and color performance were also investigated. With nitrogen fertilizer applied on turfs, desirable turf color was maintained during a period of poor coloration in specific seasons such as mid-summer for cool season grasses and late fall for warm season grasses comparing to the non-treatment. However, this was not stimulated by cutting treatment to nitrogen status existed. Cutting effect on coloration was more remarkable in both Korean lawngrass and Manilagrass than in cool season turfgrasses such as Italian rye-grass, perennial ryegrass and tall fescue. Especially down-slide of leaf color in cool season turfgrasses could he detected in mid-summer /early fall season ranging up to mid-September. In early November as well as mid-September, Italian ryegrass, perennial ryegrass and tall fes-cue retained a high level of green color as followed by nitrogen application and cutting treatment, and little detectable variation of leaf color notation between cool season turfgrasses was obtained. However, Korean la'vngrass and Manilagrass failed to retain the green color until early November. Color notations in cool season turfgrasses investigated early November on the final date of the experiment ranged from 5 GY 3/1 to 4/8 in 'Ramultra' Italian ryegrass, 'Reveile' perennial ryegrass and 'Arid' tall fescue, but those in Zoysiagrasses were 7.5 YR 4/8 in Korean lawngrass and 2.5 y 5 /6 in Manilagrass. Life-span of leaves was shorter in Italian ryegrass, perennial ryegrass and tall fescue than in beth Korean lawngrass and Manilagrass with and without nitrogen application. In general, leaves appeared in early May had a long life-span than those appeared in late April or mid-June. Nitrogen application significantly prolonged the green color retaining period in perennial ryegrass, Italian ryegrass, Korean lawngrass and Manilagrass, and this was contrasted with the fact that there was no prolonged life-span of leaves emerging in early May and mid-June in tall fescue. SPAD reading values in 48 turfs and cover plants investigated in the field trial were increasing until late June and again decreasing till September. Increasing trends of reading value could be observed in the middle of October in most of grasses. On the other hand, clovers and reed canarygrasses did not restore their color values even in October. Color differences between inter-varieties, and inter-species occurred during the growing season under the field condition implicated that selection of species and /or cultivars for mixture should be taken into consideration. In Munsell color notation investigated in the final date in the middle of November, 32 cultivars belonged under the category of 5 GY and 10 cultivars under the category of 7.5 GY. This was implying that most of cool season turfs and cover plants grown in the center zone of Korean Peninsula which are able to utilize for landscape use can bear their reasonable green color by early or mid-November when properly managed. The applicable possibilities of SPAD readings and Munsell color notation to determine the color status of turfgrasses and cover plants used in this study were discussed.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1529-1535
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• 1999

This study was done for the extraction of carotenoid from Phaffia rhodozyma in combination with PEF and other methods. PEF treatment conditions were $30{\sim}80\;kV/cm,\;100{\sim}1000\;Hz\;and\;100{\sim}1000\;{\mu}s$. In order to increase permeability of yeast cell wall, various methods such as freezing-thawing, mechanical treatment, solvents, permeabilizing agents, and yeast cell wall lytic enzyme were used before PEF treatment. The combination of PEF $(50\;kV/cm,\;300\;Hz,\;1000\;{\mu}s)$ and conventional methods such as solvent and freezing-thawing pre-treatment had no effects on the extraction of carotenoid pigments. The extent of extracted carotenoid by the PEF $treatment(50\;kV/cm,\;300\;Hz,\;1000\;{\mu}s)$ combined with yeast cell wall lytic enzyme and mechanical pre-treatment increased 52% and 69.8% more than the sum of that by each treatment, respectively. Permeabilizing agents, especially Tween 20 and capric acid, enhanced the extraction efficiency of carotenoid pigments from P. rhodozyma cells. These results indicated the feasibility for the continuous extracting carotenoid pigments from P. rhodozyma by PEF combined with other permeabilizing methods.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.4
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• pp.383-388
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• 2011

This study was carried out to determine the effect of seeding dates of Italian ryegrass interseeded into bermudagrass sod on the forage productivity and botanical composition of Italian ryegrass and bermudagrass. Experimental plot was located at 200 m altitude within Subtropical Animal Experiment Station, National Institute of Animal Science in Jeju from 2009 to 2010. Seeding date treatments of Italian ryegrass into bermudagrass sod were arranged in a randomized complete block design replicated three times. Italian ryegrass was drilled in row 20 cm apart after clipping the bermudagrass at a cutting height of 2~3 cm. Seeding time was on 15 September, 30 September and 15 October. The dry matter yield of Italian ryegrass was higher in 15 September seeding treatment, the dry matter yields of 30 September and 15 October seeding treatment were not different. The Italian ryegrass interseeded into bermudagrass sod didn't affect the dry matter yield in the summer harvests of bermudagrass, and the dry matter yield of bermudagrass showed the highest in August. In botanical composition, Italian ryegrass showed to reduced growth in early seedling stage after seeding by competition with bermudagrass, but Italian ryegrass was dominant to June increasing of temperature in spring next year and bermudagrass after Italian ryegrass harvests was dominant during summer season.

• Journal of Korean Home Economics Education Association
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• v.18 no.2 s.40
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• pp.63-77
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• 2006

The Purpose of this study is to provide the basic data for the improvement or the contents or clothing curriculum in the 7th technology home economics of middle school. The standard of satisfaction of students' according to the detail domains and the standard of necessity and practical use and learners' patterns of activity task suggested in textbooks were evaluated. The ninth grade 169 boy students and 336 girl students in the national capital region were participated in this survey. According to the survey results, firstly, a dress domain got the highest relative importance(28.56%) while a clothes material domain took the lowest relative importance(8.07%) among various detail domains. Secondly, the standard of satisfaction according to each detail domain fell below the average. Generally girls' satisfaction for teaching was higher than boys'. Thirdly, a clothes material domain showed the lowest necessity for textbook contents according to detail domain and other domains showed above the average. The necessity for textbook contents appeared high for boy students rather than girl students. In addition, boy and girl students did not have interest in content relevance in textbook. Especially, they could not do well and understand experiments and practices in clothing section. Finally, The degree of utilization of the activity task ill textbooks was very low. Among various activity tasks, the learning by discovering and exploring were more utilized than cooperating learning.

• Journal of the Korean earth science society
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• v.39 no.5
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• pp.419-435
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• 2018

The purpose of this study is to understand meteorological and climatological factors that have influence on the garlic product in Seosan and Taean, and to analyze the economic value according to the use of climatical information data for garlic farmers. The climatological characteristics and trends in this area are analyzed using the meteorological data at the Seosan local meteorological agency from 1984 to 2013, the national statistical data for the product of garlic from 1989 to 2013, and the scenario data for climate change (RCP 4.5 and 8.5) for the period from 2001 to 2100. The results are as follows. First, the condition of lower temperature for garlic growth in winter season is satisfied with the mean air temperature. The wind speed are lower and stronger in Seosan and Taean than other garlic area. The suitable condition for the growth of northern type of garlic shows the decreasing trend in the accumulated precipitation in May. However, the area of growing the northern type garlic in the future is likely diminished because mean air temperature, accumulated precipitation, and mean wind speed are strong in the harvest time of garlic. Second, the seedtime of the northern and southern type of garlic using climate change scenarios (RCP 4.5, 8.5) in Seosan and Taean is getting late as time passes. and the harvest time gets faster, which indicates s that the period of garlic cultivation becomes shorter from 50 days to around 90 in the next 100 years. Third, the beginning days of white rot and delia platura of garlic are estimated by applying to the meteorological algorithm using mean air temperature and soil humidity. Especially, the beginning day of white rot garlic is shown to be faster according to the scenarios of RCP 4.5 and RCP 8.5. Fourth, the product of garlic (kg/10a) shows a high correlation with the minimum air temperature of a wintering time, the mean wind speed of a wintering time, the accumulated precipitation of a corpulent time, and the mean relative humidity of corpulent time of garlic. On the other hand, the analysis of garlic product when using the meteorological information data in cultivating garlic in Seosan and Taean reveals that the economic value increases up to 9% in total.

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.1
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• pp.29-39
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• 2015

This study has attempted to determine the micro-discourse from blogs as personal media that reflect citizens' actual opinions of the Seoul Forest without intervention of experts. Furthermore, a qualitative research method discourse analysis was selected to analyze the micro-discourse regarding the Seoul Forest in a time series. The extracted samples of blogs by year were intended to identify the comment section of the process of change and the discursive structure. The results are as follows; first, from the beginning of the development of the Seoul Forest to the present, it is divided into four chronological periods along with individuals' micro-discourse with social changes. During the beginning of the development of the Seoul Forest, the social discourse was formed, and in the next period, the micro-discourse was developed with a more emotional and complex discourse. In the formative period, four or five years later, the discourse reflected the civic consciousness of development more than ever, showing the diversity of participation in the program at the Seoul Forest. In the growth period, as the users' experiences had been accumulated, the users started writing about the role of the Seoul Forest in their own words. This can also be called place discourse. From the individuals' micro-discourse, this study shows the discourse structure of how individuals think about the Seoul Forest in each period. Unlike the experts, the micro-discourse contains specific daily interactions, experiences, and the stories of individuals who actually use the parks. It also shows how users reproduce and understand the space. In this respect, this is the most significant finding of this study. Based on this research, this study has demonstrated that the emotional description of a place that actually functions as a discourse about city parks, and confirms that blogs could be used as a space to form discourse and as a research tool to read the trends. In accordance with these results, this study has described not only the discourse of experts, but also how the discourse of individuals' comments can be an important part of the discourse of modern urban parks.