• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.213-214
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• 2005

Uiryung Watershed area, located at the confluence of Nam River and Nagdong River has 9000 ha of agricultural land area and 3024 ha of paddy rice field have been reclaimed and managed by Korean Agricultural and Rural Infrastructure Corporation(KARICO) in the riparian area since 1954. In spite of irrigation and drainage improvement projects in last 3 decades since 1970, there are severe drought and innundation problems in the area. To improve the difficulties and efficient usage of irrigation water not only for agriculture but also for environmental conservation and cultural ceremony, Automatic Water management system has been installed supported by Ministry of Agriculture and Fishery in Korean Government. The control office in Uiryung Branch Office of KARICO, receive all the water management records from Remote Terminal Units in 7 reservoirs and 26 Pump stations to operate the decision supporting system of irrigation and drainage facility during cropping period. Since the completion of the water management system at the end of 2003, the electric cost decrease in 80 % than average years. In spite of decrease of two technical assistants since 2004, complains from farmers for the water management are very rare. The technological experience from the automatic water management system would contribute not only for the efficient water management of Uiryang area but also for the modernization of water management of other watershed areas in the future.

• KSBB Journal
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• v.31 no.1
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• pp.79-84
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• 2016

Biofuel has been considered as promising renewable energy to solve various problems that result from increasing usage of fossil fuels since the early 20th century. In terms of chemical and physical properties as fuel, biobutanol has more merits than bioethanol. It could replace gasoline for transportation and industrial demand is increasing significantly. Production of butanol can be achieved by chemical synthesis or by microbial fermentation. The water hyacinth, an aquatic macrophyte, originated from tropical South America but is currently distributed all over the world. Water hyacinth has excellent water purification capacity and it can be utilized as animal feed, organic fertilizer, and biomass feedstock. However, it can cause problems in the rivers and lakes due to its rapid growth and dense mats formation. In this study, the potential of water hyacinth was evaluated as a lignocellulosic biomass feedstock in biobutanol fermentation by using Clostridium beijerinckii. Water hyacinth was converted to water hyacinth hydrolysate medium through pretreatment and saccharification. It was found that productivity of water hyacinth hydrolysate medium on biobutanol production was comparable to general medium.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.9
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• pp.925-932
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• 2008

Adsorption performance of tetracycline antibiotic compounds such as tetracycline(TC), oxytetracycline(OTC), chlortetracycline (CTC) and minocycline(MNC) on granular activated carbon(GAC) was evaluated in this study. The coal-based activated carbon was found to be more effective than other carbons in adsorption of tetracycline antibiotic compounds. The wood-based activated carbon was less effective than coconut- and coal-based carbon in adsorption nevertheless having larger pore volume and specific surface area than others carbons. The maximum adsorption capacities(X/M) of coal-based activated carbon for the four tetracycline species was 1.27$\sim$1.36 and 1.69$\sim$1.84 times larger than coconut- and wood-based activated carbon, respectively. Carbon usage rates(CUR) of coal-, coconut- and wood-based activated carbons for tetracycline(TC) were 2.96 g/day, 3.40 g/day and 4.53 g/day, respectively. Similar results were obtained in the adsorption of the rest three tetracycline species. It is concluded that coal-based activated carbon could removed the tetracycline antibiotic compounds better than other material-based activated carbons.

• International Journal of Highway Engineering
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• v.11 no.2
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• pp.185-194
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• 2009

The autogenous shrinkage of high-performance concrete, including very-early strength latex-modified concrete(VES-LMC), is generally bigger than that of normal strength concrete because of the low water/cement ratio, high binder contents, and usage of superplasticizer. Mix. proportion of VES-LMC has low water/cement ratio(0.38), high cement content(390kg/m$^3$), and aid of latex(15% of cement weight). Thus, these factors of VES-LMC, rapid water self-dissipation and evaporation within 3 hours of concrete placement would increase the autogenous shrinkage. The purpose of this study was to evaluate the early-age shrinkage, thermal deformation and autogenous shrinkages of VES-LMC with retarder contents(retarder solids-cement ratio, by weight) using to secure working time in field. The experimental results showed that retarder contents do not affect of the maximum hydration temperature. Early-age expansion of VES-LMC was mostly caused by thermal expansion and partly by autogenous expansion. The autogenous shrinkage is decreased by increasing the retarder contents within this study. On the other hand, the usage of retarder should be decided carefully considering the field conditions because an excessive usage of retarder can cause handful early-age expansion.

• The Journal of Engineering Geology
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• v.25 no.1
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• pp.35-43
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• 2015

A method is proposed to estimate groundwater usage for water curtain cultivation (WCC) using a rating curve, and it is applied to field measurements of groundwater discharge used for WCC in Wangjeon-ri, Nonsan. During the winter season, the hydraulic components of irrigation ditches in the study area consist mainly of direct run-off and groundwater discharged from nearby pumping wells. Changes in stage of the ditches were monitored, and a baseflow separation method was applied to remove increments in stage due to direct run-off. The resulting records of stage were translated to groundwater discharge by applying the-stage-discharge relation. The estimated average groundwater discharge for the WCC in Wangjeon-ri was 10,900 m³/d or 420 m³/d/ha when the estimation is normalized by the total area for WCC facilities of this region. Applying this estimation (420 m³/d/ha) to the entire area of the WCC in Korea (10,746 ha),and considering the number of pumping days for the WCC (120 days/year), the total ground water usage for the WCC nation-wide is estimated to be 0.54 billion m³. This is equivalent to 32% of the total groundwater discharge for agricultural use in Korea (1.7 billon m³).

• Journal of the Korean Institute of Landscape Architecture
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• v.27 no.4
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• pp.1-12
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• 1999

This study aims to find basic data for using the quantitative assessment of the sustainability and establishing the systematic index of the planning for local cities to consider the environmentally sound and sustainable development. The research designs to review professional responding to surveys preceded by separate questionnaires and interviews from book reviews, and suggests to make an assessment model of the sustainability for local cities. The research found consequently as follows. Firstly, the research survey items were decides totally 52, grouped 9 assessmental issues and distributed under 4 assessmental domains for the sustainability from the references of book reviews. Secondly, the research result concentrated on the followings from the professional responding to surveys. 1. A most influent factor is the distribution of animals and plants in a nature domain. The next influent factors are the ratio of mass-transportation systems, the numbers of the species of animals and plants, the acreage of conservative forestry, the numbers of reused water resources, and the usage number of water supply, orderly in the nature domain. 2. A most influent factor is the usage number of synthetic detergents in a pollution domain. The next influent factors are the volume of waste water, the number of registered vehicles, the degree of soil pollution, and the charge of development imposition, orderly in the pollution domain. 3. A most influent factor is the acreage of athletic facilities, in an urban domain. the next influent factors are the acreage of recreational facilities, the number and acreage of cultural assets, the number of cultural facilities, the acreage of landscape conservation area, the charge of cultural asset management, orderly in the urban domain. 4. A most influent factor is the number of waste disposal facilities in a participation domain. The next influent factors are the capacity of reused waste, the usage of synthetic detergents, the ratio of waste water disposal, orderly in the participation domain. 5. A most contributed influent domain to the assessment of the sustainability for local cities is the urban domain. The next influent domains are nature domain, participation domain, and pollution domain, orderly in the contribution of the assessment of the sustainability. But, the pollution domain is little relationship with the sustainability. Therefore, it is clear that the abundant greens and the improved level of culture are dominant influences on the sustainabiligy, as like improving the ratio of roadside trees, the acreage of parks, and enlarging the number of cultural facilities.

• Journal of Korean society of Dental Hygiene
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• v.10 no.6
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• pp.1107-1119
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• 2010

Objectivs : The purpose of this study is to provide basic data for the use of oral hygiene devices and to improve oral health care continuously by encouraging the use of oral hygiene devices. Methods : The survey was carried out by questionnaire research targeting 395 respondents in metropolitan area in June-August 2009. The collected data is analyzed by statistics program SPSS version 12.0. 1. General characteristics of subjects are analyzed by percentage and descriptive statistics. 2. Recognition about how to use oral hygiene devices, usage of oral hygiene devices, recognition of dental brush usage, Effect after using oral hygiene devices are analyzed by mean difference test(t, F verification). 3. Effect after using oral hygiene devices, relation of oral hygiene devices usage with subjective oral health status, oral hygiene devices usage and participation in education are analyzed by Correlation, Regression analysis. Results : 1. Investigation shows that most oral health devices are rarely used except toothbrush(4.57) in case of the use of oral hygiene devices. 2. In the case of awareness of oral hygiene devices usage, almost everyone knows how to use dental brushes(MEAN 4.16) the most. And the next ones are like these-tooth picks(MEAN 3.38), dental floss(MEAN 3.28), mouth rinse(MEAN 3.24). And they don't know how to use the other oral hygiene devices usage. 3. respondents who use dental floss(${\beta}$=.238, p<.001), interdental brush(${\beta}$=.242, p<.001) and water pik(${\beta}$ =.180, p<.05) recognize that the result and effect after using them are more positive than the others in different case. 4. Respondents who use toothbrush(${\beta}$=.119), dental floss(${\beta}$=.120) and interdental brush(${\beta}$=.136). frequently evaluate their subjective oral health status positively in case of frequency of using oral hygiene devices and subjective oral health status(p<.05). 5. Respondents who use toothbrush and interdental brush properly and frequently, who are older than the others show more concern about participating in education of "How to use oral hygiene devices" than the others(p<.05). Conclusions : In conclusion, to prevent oral disease, the opportunity of participating in education about correct knowledge and proper way should be expanded. And we should contribute to oral health improvement through developing, executing and informing systematic, popular oral health education with active one.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.10
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• pp.656-663
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• 2012

After the construction of waterworks automatic meter reading with 15 mm diameter digital water mater with magnetoresistance sensor developed in this study at 96 households of apartment complexes located in Incheon-City B-Gu S-Dong, the feasibility of field application of waterworks automatic meter reading was evaluated. The field application of waterworks automatic meter reading was performed from July to December in 2011, and average reception rate was as low as 84.6% due to the instable wibro networks, the existence of communication blackout and temporary malfunction of router. After the extraction of 10 households with one to five residents out of 96 households by using stratified random sampling method and analysis of domestic water use, it was found that domestic water use was significant at August and showed a decreasing trend at September, followed by increase in domestic water use at November and decrease in domestic water use at December. This phenomenon should be attributed to weather factors (temperature, humidity, etc.), which significantly affected domestic water use. Similar trend in domestic water use in terms of weather factors was obtained in case of Liter per capita day of water use after the extraction of 30 households out of 96 households by using stratified random sampling method. After analysis of Liter per capita day for 96 households, single residents increases resulted in reduction of domestic water usage by about 14% of Liter per capita day. These results might be due to the fact that domestic water usage such as laundry, beverages, catering, cleaning, etc. should be required for even the household with one resident, whereas domestic water usage for those common utilization can be significantly saved for the household with more than one resident.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.19-20
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• 2015

In this research, by examining the influence that high quality fine aggregate and low quality fine aggregate have on the strength of concrete through tests, the manifest strength of concrete according to high quality fine aggregate was reviewed. The results showed that compared to low quality fine aggregate usage mixture, the unit volume to achieve the same liquidity decreased and accordingly the W/B also decreased therefore increasing the strength of concrete, and as high quality fine aggregate was used, it is determined that there can be improvements to the economically feasibility of usage mixture and improvement in durability etc.

• Journal of Fashion Business
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• v.20 no.6
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• pp.52-65
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• 2016

Presently, sleep disorders are rapidly increasing due to sudden social development and lifestyle diversification. Among the various factors contributing to comfortable sleep, bedclothes are a major factor that readily influence the sleeping conditions, as they directly come in contact with the human body. This study therefore researches use and purchasing status of bedclothes by consumers, as well as the subjective satisfaction. This would accordingly help us to understand the consumers' performance needs, and collect basic data to develop bedclothes that assist comfortable sleep. This study used multiple choice questions and a 5-point Likert scale in a survey-style research. The results of the study indicate that consumers prudently considered practicality and durability, as bedclothes are seldom purchased. The most preferred material was cotton, but the use of microfiber, a new material, has also increased. Further, consumers' preferred lightweight bedclothes that displayed excellent water absorption, thermal insulation, durability, detergency, and flexibility. Hence, bedclothes developed according to the results of this study are expected to aid comfortable sleep.