• Journal of Engineering Education Research
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• v.12 no.4
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• pp.142-149
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• 2009

This paper deals with the analysis and comparison between on the course of a conventional engineering design (typically project-based learning) and a new engineering design (introduced PBL model to conventional engineering design). The purpose of the study is to identify and prove the effect of PBL model on the course with a new teaching-learning. In the result of t-test, there were significant statistics in the creative problem solving and self-directed learning ability, but no significant statistics in the team work and communication skill ability. Also the average of factors of the problem-based strategy is higher than those of the project-based strategy. In the problem-based strategy, the team work has the most influential on the satisfactory of the course. However in the project-based strategy, the comprehension of given product has the most influential on the satisfactory. Finally, this study has proved the effect of PBL on the course engineering design.

• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.1
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• pp.1-10
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• 2011

To understand characteristics of the water quality on the coastal boundary on tidal flat, field observations between 2008 and 2009 were undertaken twice a month at five coastal areas (Muan bay, Tando bay, Hampyeong bay, Shinan Jido and Yeongkwang coastal areas). Yearly water temperature difference was large with the range between $1.3^{\circ}C$ and $31.1^{\circ}C$. Salinity was about 32 but was the lower less than 20 for the heavy rainfall season. DO was high in winter and low in summer according to the variation of water temperature. pH represented the variation similar to DO. Suspended solid was averagely high over 100 mg/l in Yeongkwang coastal area, especially. COD did not revealed large variation with the value of about 1 mg/l. DIN and DIP concentration were high when freshwater was highly input in summer. DIN concentration was low for winter and early spring but DIP concentration did not show the seasonal variation with the continuous increase from July 2009 to December 2009. Chlorophyll a appeared high for spring with approximately $10\;{\mu}g/l$ and was higher for summer in Yeongkwang coastal area than other sites. The results of principal component analysis conducted to compare the characteristics of water quality observed in study areas showed the distinguishable features as follows. The freshwater input fluctuation appeared as the first factor in Muan and Tando bays, and the change of water temperature was the first factor in Shinan Jido and Yeongkwang coastal areas. The influence mixed with the variation of freshwater outflow and the change of water temperature in Hampyeong bay was to be the first factor.

• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.542-549
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• 2018

In this study BGn-incorporated non-fluoride release of pit and fissure sealant $Concise^{TM}$ was developed to improve the mechanical properties and promote antibacterial effect of fit and fissure sealant with the original material. The mechanical properties and antibacterial activity of BGn incorporating vary-ing amounts bioactive glass nano particles(BGn) (0,0.5,1.0 and 2.0 wt% in sealant) were characterized composition of the resulting were investigated. The solubility to aid absorption was calculated by weighing specimens with a diameter of 10 mm and a thickness of 2 mm according to ISO 4049 (2009). The antimicrobial effect was evaluated using three strains of S. mutans, S. aureus and E. coli. The absorbance of the test results was as high as the addition of BGn increased, and the lower the solubility as the solubility was added(p<0.05). Adhesion experiment results S. mutans in contrast to the control group $Concise^{TM}$, BGn-added experimental group showed a somewhat lower adherent surface but no statistically significant difference was observed (p<0.05). However S. aureus and E. coli statistical analysis indicated a significant difference for antibacterial agents between control and BGn containing(p<0.05). It seems that this BGn proved that even a antibacterial effect was demonstrated. Therefore, it was suggest that the additional effects of BGn and research on a wide range of substances.

• The Korean Journal of Mycology
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• v.12 no.3
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• pp.93-98
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• 1984

The effects of cultural conditions on the mycelial growth and fruit-body formation and the yield of Pleurotus sajor-caju grown in rice straw medium were examined. The change of content of chemical components of mushroom and the medium during the cultivation period was also examined. The growth of mycelium was best in the medium sterilized for 60 min at $1.2kg/cm^2$ with a moisture content of 60%. The optimum pH and temperature for mycelial growth were 6.0 and $25^{\circ}C$, respectively, whereas the optimum pH and temperature for fruit-body formation ranged from 5.0 to 6.0 and from 20 to $30^{\circ}C$, respectively. Rice bran and starch cake were better than the other additives used for both mycelial growth and fruit-body formation. The optimum concentration of rice bran in the medium was 10%. The total yield of mushroom was $20.2kg/m^2$, 66% of which was prouduced from the first and second cropping period. As the harvest proceeded, the crude fiber cotent increased in the mushroom, whereas it decreased in the medium. The content of free sugar and crude ash, on the other hand, decreased in the mushroom, whereas it increased in the medium. The content of the other chemical components examined decreased in both the mush­room and the medium.

• Korean Journal of Social Welfare
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• v.67 no.3
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• pp.31-55
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• 2015

The purpose of this study is to identify the effect of verbal violence experience by employees on turnover intention and the mediating effect of customer-member exchange(CMX) and job satisfaction in local healthy family support center(HFSC). Additionally, the multi-group analysis and latent mean analysis showed varying results across working for general service and child-care service. For the purpose, study conducted a survey among all the employees at 56 local HFSC in Seoul and Gyeonggi-do Province. Of a total of questionnaires distributed, 319 were returned and analysed. The result of this study were as follows First, verbal violence experience by employees effected on CMX, CMX effected on job satisfaction, job satisfaction effected on turnover intention. Second, CMX and job satisfaction acceptance have statistically significant mediating effects between verbal violence experience and turnover intention. Third, as result of multi-group analysis, the structural relationship were no significant differences found in job position. In the latent means analysis, working for child-care service showed significantly higher latent mean values in verbal violence experience and CMX than general service. Based on the results, policy and practice implications of this study were discussed intervention with considerations given to the difference of the job position.

• Korean Journal of Ecology and Environment
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• v.37 no.4 s.109
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• pp.363-367
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• 2004

For comparative analysis of the eubacterial community structure at 8 sampling sites throughout the Nak-Dong River, FISH (fluorescence in situ hybridization) method was employed. The total ratio of each determined eubacterial group such as ${\alpha}\;{\cdot}\;{\beta}\;{\cdot}\;{\gamma}-subclasses$proteobacteria and Cytophaga-Flavobacterium(CF) group to total counts(DAPI) at each site varied 9.3-42.5% with the highest value at uppermost part. And each ratio of determined eubacterial groups reached mostly under 10% except that of CF group (23%) at uppermost part. Furthermore, compared to lower part, upper part represented unexpectedly higher proportions of ${\gamma}-subclass$ proteobacteria comprised almost fast growing bacteria on degradable organics. Also the variations of ammonia-oxidizing bacteria ranged from $2.7{\times}10^4$ to $18.0{\times}10^4$ cells $mL^{-1}$ with the lowest value in lower part and the highest value in mid part whereas those of nitrite-oxidizing bacteria varied 5.2-7.7{\times}10^4$ cells $mL^{-1}$ without noticeable differences throughout the sites. Additionally, the ratio of nitrifying bacteria to total counts ranged from 1.0% to 13.6% with no differences between ammonia-oxidizing bacteria and nitrite-oxidizing bacteria. In conclusion, FISH method introduced in this study for monitoring, normally used for the quantitative analysis of bacteria, provided also good information on their environmental status in the Nak-Dong River.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.384-384
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• 2011

전 세계적으로 유역단위 수문해석 모형으로 많이 사용되는 SWAT모형은 유역 내 수문 모의시, DEM을 기반으로 유역 평균경사도를 이용하여 경사도-경사장 관계식 산정 경사장을 유역 내모든 수문학적 반응단위(HRU:Hydrologic Response Unit)에 동일하게 적용하는 문제점이 있다. 특히 SWAT모형은 미국지형 기반으로 개발되었기 때문에 유역 평균 경사도가 25% 미만일 경우 유역 평균 경사장 인자가 매우 작은 값으로 산정되어 모두 동일하게 적용된다. 이는 SWAT모형의 수문 및 지하수 함양량 산정 시 우리나라 유역 특성이 제대로 반영되지 않는 채 모의가 이루어질 수 있는 문제를 초래할 수 있다. 따라서 이러한 문제점을 해결하기 위하여 본 연구에서는 강원 발전연구원에서 전수 조사한 실측 경사장 자료가 있는 강원도 양구군 해안면 만대천 유역을 연구 대상지역으로 선정하였고 지하수 함양량을 시공간적으로 분석 할 수 있게 개발 된 SWAT HRU Mapping module에 실측 경사장 자료를 이용하여 2009년 실측 경사장(274m) 적용과 임의의 경사장(5m) 적용에 따른 유출량 및 지하수 함양량을 비교 분석 하였다. 임의의 경사장을 5m로 선정한 이유는 SWAT모형에서 소유역의 경사도가 25%이상일 경우 소유역의 경사장을 모두 0.05m로 산정하여 모두 동일하게 적용하기 때문에 실측 경사장(평균 274m)과 대조군으로 비교하기 위하여 임의의 경사장을 5m로 선정하였다. 2009년 해안면 만대천 유역의 총 강우량은 1341mm이며 실측경사장 및 임의 경사장 적용에 따른 유출특성별 유출량을 비교해보면 직접유출 결과는 두 가지 경사장 모두 큰 차이를 나타내지 않았지만 평균 경사장이 증가 할수록 중간유출은 줄어들고 기저유출이 급격하게 증가하는 것으로 분석되었다. 또한 2009년 만대천 유역의 월별지하수 함양량은 실측경사장과 임의의 경사장 적용에 따라 각각 591mm/yr(함양율 44%) 와 293mm/yr(함양율 22%) 로 나타났으며, 중간유출이 줄고 기저유출이 증가 할수록 지하수함양량 역시 증가 하는 것으로 나타났다. 따라서 SWAT모형에서 기저유출을 정확히 해석하고 지하수함양량을 제대로 산정하기 위해서는 실측 경사장에 적용에 따른 모형의 검 보정이 반드시 이루어져야 한다고 판단된다.

• Journal of the Korean Society for information Management
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• v.31 no.4
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• pp.249-266
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• 2014

In South Korea, systems related to the provision of public data were recently implemented. As a result, policy changes have been made that are headed in the direction of actively providing open access to data held by public institutions, such as government agencies and local municipalities. The purpose of the open I will be divided into two broad. To ensure the transparency of government operations, and is intended to satisfy the right to know the people. The other one is to create national interest by utilizing the public data as one country endowment assets. In this study, we analyze the open situation of public data, were presented the improvement measures. Range of research, the public data that local government owns, to determine to have a central information and other limitations and characteristics, Seoul the beginning to the seventeen regional support municipality 228 that you have held for city districts were census. According to the research results, local governments, themselves produced, is a relatively reluctant to disclosure and understanding of the list of public data that are holdings. According to the research results, local governments, themselves produced, is a relatively reluctant to disclosure and understanding of the list of public data that are holdings, also emphasizes the conservative value than take advantage of value have had. Therefore, it was determined that there is a need to resolve several issues through disclosure via a linked data format as a strategy to increase the openness and utilization of local public data.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.5
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• pp.303-311
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• 2015

To determine the concentrations of selected 10 perfluorinated compounds (PFCs), a field study was conducted in the water body of Yeongsan River Water System. Raw water samples were collected in the spring and the fall, respectively, which included 18 sampling sites. Collected samples were equally mixed and then served as an analytical sample. The concentration of perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) were in range of 20.80-92.0 ng/L and ND-28.40 ng/L respectively. Perfluorononanoate (PFNA) and perfluorohexanesulfonate (PFHxS) were ranged from ND to 42.20 ng/L and from ND to 11.47 ng/L. The detection frequencies of other PFCs selected in this study were very sparse at very low concentrations, except for PFOS, PFOA, PFNA and PFHxS. PFOS was higher detection frequency and concentration in both spring and fall, PFOA and PFNA were in spring, and PFHxS was in fall. As a result, the observed concentrations of PFCs in the downtown water area of Gwangju, located in the wastewater treatment plants, were relatively higher than other sampling points.

• Journal of Gifted/Talented Education
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• v.22 no.2
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• pp.243-264
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• 2012

The purpose of this study was to investigate the current status of R&E programs in gifted high schools/science high schools and to provide suggestions for the better program. The sample included 21 R&E coordinators in the gifted high schools and science high schools. They filled out the survey, asking about the R&E program; then, the researchers interviewed the coordinators based on the answers of the survey. The results are as follows: 1) The R&E guidelines and related materials were not enough to use. 2) At the planning step, students and the mentors received were provided a little information, such as ethical issues, students' information, the roles of mentors/ students, mentor's research interest areas and products, etc. 3) At the research step, 80% of the schools had the monitoring process but the details were not written and saved. 4) At the evaluation step, the rubric of the product evaluation existed; the rubric of performance process were established by half of the schools. 5) At the closing step, 100% of the schools had the final product materials; the results of the evaluation and the information of the mentors were saved by 2/3 and 1/3 of the schools, respectively. Discussions and suggestions were included for the better R&E programs.