• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.2
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• pp.77-86
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• 2012

This study was aim to predict future land-cover changes and to analyze regional land-cover changes in irrigation areas and agricultural reservoir watersheds under climate change scenario. To simulate the future land-cover under climate change scenario - A1B of the SRES (Special Report on Emissions Scenarios), Dyna-CLUE (Conversion of Land Use Change and its Effects) was applied for modeling of competition among land-use types in relation to socioeconomic and biophysical driving factors. For the study areas, 8 agricultural reservoirs were selected from 8 different provinces covering all around nation. The simulation results from 2010 to 2100 suggested future land-cover changes under the scenario conditions. For Madun reservoir in Gyeonggi-do, total decrease amount of paddy area was a similar amount of 'Base demand scenario' of Water Vision 2020 published by MLTMA (Ministry of Land, Transport and Maritime Affairs), while the decrease amounts of paddy areas in other sites were less than the amount of 'High demand scenario' of Water Vision 2020. Under A1B scenario, all the land-cover results showed only slight changes in irrigation areas of agricultural reservoirs and most of agricultural reservoir watersheds will be increased continuously for forest areas. This approach could be useful for evaluating and simulating agricultural water demand in relation to land-use changes.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.8
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• pp.65-72
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• 2019

The purpose of this study was to explore the influence of the topography and the neighborhood facility on the aged people's social network formation. The paper samples the aged people living in Changchun city located in a flat ground and Tonghua city located in a mountain region. Four selections of dwelling districts from the two cities are based on amount of the facilities maintaining the wealth and living area same to do the questionnaires. One hundred aged people are selected in the each dwelling district to fill out the questionnaires, and 386 valid questionnaires are finally obtained. The data obtained from the questionnaires are used to do some statistic analysis by using SPSS24.0 program. The results are shown as following: In the case of same amount of neighborhood facility for dwelling district, the aged people living in a flat ground use the facility more frequently and communicate more often with their friends and neighbors than the aged people living in a mountain region do, the social network forms more easily as well. In the other case of same topography dwelling districts, the aged people living in an abundant facility dwelling district use the facility more frequently and communicate more with their neighbors and friends than the aged people living in a mountain region do, so the social network forms more easily as well. Thus it can be seen that topography and amount of facility are significant influence factors of the aged social network formation.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.1
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• pp.100-110
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• 2003

The purpose of this study were 1) to find out the structural elements in classifying clothes images, and 2) to segment the consumer market for women's street clothes based on clothes image preferences and to identify the group differences in psychological variables, purchasing behavior variables and demographic variables. The sample was taken from 1106 middle class women who were in thier 30's∼40's living in Gwangju city. Consumers were classified into six groups: active image group (35.4%), feminine image group (25.9%). daring image group (16.5%), elegant image group (10.8%), dressy image group (8.9%) and brisk image group (3.5%). Women in their 30's∼40's preferred elegant image, daring image, active image and feminine image. Elegant image oriented group: This group is the lowest education level group and has the highest rating of housewife. This group has the lowest scores use of person information search, Daring image oriented group: Woman in their 30's prefers daring image. This group thinks practical benefit sought is less important than self-expression benefit sought. This group has the highest scores use of non-person information search, Active image oriented group: This group is practical benefit seeking group. and purchases the lowest amount of clothes. The amount of average household income is the lowest. Feminine image oriented group: The amount of average household income is the highest. This group perceives more youth$.$fashion benefit sought and self-expression benefit sought than elegant image oriented group. ANOVA, $\chi$$^2$-test revealed differences among groups according to benefit sought use of information sources, purchasing behavior variables and demographic variables.

• Journal of Family Resource Management and Policy Review
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• v.22 no.3
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• pp.1-19
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• 2018

This study was aimed at exploring gender differences in time use and time famine between single-parent families. Data were obtained from the time use surveys, that were conducted by the Korea National Statistical Office in 2014. A total of 500 time diaries (168 from fathers, 332 from mothers) from single-parents aged between 20 and 59 were analyzed. Descriptive statistics, chi-square test, and t-test were used for the statistical analyses. Results indicated that the single-parent families exhibit gender differences in time use and subjective time famine. The single-mothers spend a significantly longer amount of time on housework and less time on leisure than do the single-fathers. The single fathers and mothers also differ in time use and time famine according to employment status and working days on/off.

• Journal of Korea Foundry Society
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• v.14 no.1
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• pp.75-81
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• 1994

It is very important to obtain high performance ductile iron by addition a small amount of alloying elements. In this study, to improve the characteristics of small piston ring casted from ductile iron melt a small amount of boron($0{\sim}0.008wt.%$) that is powerful carbide stabilizer was added in ductile iron, and inspected it`s effects on the microstructure, wear resistance, machinability and mechanical properties. The results obtained from this study are as follows. 1. As the amount of boron increased to 0.04wt.%, the machinability of ductile iron is increased, and if the amount is in excess of 0.04wt.% the machinability is decreased conversely. 2. The wear resistance of ductile iron is improved by boron addition. 3. The recommended ladle addition of boron amount ranges from 0.04wt.% to 0.06wt.% for the use of small piston ring.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.1
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• pp.66-72
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• 2004

In this study, quantity and quality of collected rainwater by sand, gravel, soil, lawn and concrete surface, as collection materials were investigated and Rainwater Collection Prediction Model was developed to predict the amount of collected rainwater. The quantity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 1,067L(93.2%), 1,006L(87.8%), 902L(78.8%), 800L(69.9%), 788.5L(68.8%) for 8 months period, respectively. The average turbidity of collected rainwater in concrete surface, gravel, sand, soil and lawn collection system was 3.2NTU, 2.2NTU, 1.9NTU, 1.7NTU, 1.5NTU for 8 months period, respectively. For sand collection material, predicted amount by the Model and actual collected amount were 931.5L and 902L, which were very closed. For gravel collection material, predicted amount by Model and actual collected amount were 1,028.21. and 1,006L, which were very closed. To simulate the optimal rainwater storage volume, the rainfall and evaporation data in Dae-jeon city were used. For sand collection system with 30m2 area, the maximum storage volume was $17m^3$ and 62% of the year was secured for use of 240L/day.

• Korean Journal of Pharmacognosy
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• v.4 no.4
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• pp.173-179
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• 1973

Tobacco, which has nicotine for its main component, has been in medical use for a long time and in great demand for smoking throughout the world. The purpose of this study is to control nicotine amount and to increase yield more efficiently by the method of systematic variations. Nutrient solutions for tobacco culture were designed and prepared in 10 kinds with mineral ions: $NO_{3^-},\;SO_{4^{--},\;PO_4{^{-3},\;K,{^+}\;Ca,{^{++}\;Mg,{^{++}$, Mn, B, Cu, Zn, Mo, and Fe. Nicotiana tabacum L. Yellow Special A, grown for 50days from sowing, was replanted in plastic pot and cultured for 65 days supplying with prepared nutrient solutions. After harvest, their nicotine amount was determined by means of acid-base titrimetry and gas chromatography. The tobacco plants in KCa 4 and KMg 9 groups demonstrated the highest yield in total leaves weight and KMg 7 group in average nicotine amount. They have shown the increase of nicotine amount from lower leaf to 16th leaf, and thereafter decreased gradually. The author also pursued the optimum ionic proportions for the absolute nicotine amount in tobacco by means of systematic variations method.

• Korean Journal of Agricultural Science
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• v.31 no.2
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• pp.87-96
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• 2004

This study concentrates on the trail of the CNU(Chungnam National University) forest. The amount of use and the pattern of damage are considered, as well as the extent of environmental damage. Finally, some managerial strategies are proposed in connection with sustainable maintenance. The trail of the university forest is composed of three sections; one is the neighborhood park and the Institute of Information Technology/Communications, the second is the Institute of Information Technology/Communications and the Dormitory, and the third section is the Dormitory and the Foreign prof's Apt. The total length of the trail is 2.6km. The daily amount of use is 1,269 visitors per day. The amount of using increased three times the amount of that in 1998. This study shows the pattern of damage of the trail in the order of root-exposure, widening, rock-exposure, deepening and the divergence in the frequency of occurrence of all these factors. Environmental damage is also graded thus: grade 3 is 27.4m, grade 4 is 0.8m, grade 5 is 1.5m, and grade 6 is 0.2m. Accordingly, some managerial strategies were proposed in connection with the sustainable trail maintenance.

• Child Health Nursing Research
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• v.25 no.4
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• pp.487-495
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• 2019

Purpose: We aimed to identify associations between the frequency of electronic cigarette (e-cigarette) use and smoking-related characteristics among adolescent smokers. Methods: We used data from the 14th Korea Youth Risk Behavior Survey. The participants were 3,722 smokers who had smoked cigarettes on at least one day during the past 30 days. The frequency of e-cigarette use was defined as the number of days that participants used e-cigarettes during the past 30 days, and was divided into four categories: 0, 1~2, 3~9, and ${\geq}10$ days. We used the $x^2$ test and multinomial logistic regression to examine the associations between the frequency of e-cigarette use and smoking-related characteristics. Results: Those who attempted to quit smoking, had used a heated tobacco product (HTP) at least once, or initiated e-cigarette use before middle school were more likely to use e-cigarettes for 3~9 days in the past 30 days. More frequent e-cigarette use (${\geq}10$ days) was associated with a higher frequency and greater amount of cigarette use, lifetime HTP use, and earlier initiation of e-cigarette use. Conclusion: Smoking-related characteristics differed by the frequency of e-cigarette use. Therefore, intervention programs targeting adolescent smokers should consider differences in smoking-related characteristics based on the frequency of e-cigarette use.

• Korean Journal of Microbiology
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• v.5 no.2
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• pp.43-54
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• 1967

The characteristics of enzymic sources and its effective uses concerned with brewing of Yack-Tack Joo which is traditional and popular liquors for all Korean have been studied. Results obtained are as follows; 1)Kock Ja (enrich of fungi and yeast produced in Korean brewery) is found to be weak in its liquifying(600U.) and saccharifying activity(1300U.), so that it is useful to conbine two factors effectively for better brewing. 2) The additional ratio of Kok Ja per materials is seems proper at line of 20 percent for better fermentation and the enzymic preparations inoculated of microorganisms in wheat bran is seems proper at 25 percent line. 3) Adding the enzymic preperation in which the strain Rhyzopus had been inoculated to the experimental mash at 5 percent per material, the rate of fermentation was revealed highest degree than those of else. 4) It is not proper to add a single Bun Kok in fermentation, as it produce much acid in mash during brewing. 5) However, the enzymic preparation composed of Asp usami and Rhyzopus sp. produced less acid in brewing. 6) The increasing of temparature in enzymic samples, temparatures of the mixtured Kuk(Kok Ja and enzymic preparation) are higher than those of single addition at the first stage in pre-fermentation, but there are no differences at the late stage of post-fermentation. 7) Amount of amino acids in the plot of enzymic prepation are found much more than those of single use at late stage of post-fermentation. In the plot of single use of Kock Ja, the amount was the most than else, the proteinase activity is strongest more than else. 8) In the brewing of Korean Tack-Yack-Joo, it is desirable less amount of acidity, more amount of amino acid, stronger liquifaction of starch and vigorous saccharification. Thren it was found that the application of two prepations(Kock Ja and Bun kok) is most effective to get moderate quality in Tack-Yack-Joo brewing.