• 대기
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• 제18권4호
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• pp.475-483
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• 2008

The hourly precipitation data from 1973 to 2007 observed at 60 weather stations over Korea are used to characterize the diurnal and semidiurnal cycles of total precipitation amount, intensity and frequency and examine their spatial patterns and interannual variations. The results show that the diurnal cycle peaks in the morning (03-09LST) and the semidiurnal cycle peaks in the late afternoon (16-20LST). It is found that the spatial variations of the peak phase of diurnal or semidiurnal cycle relative to their corresponding seasonal mean cycle are considerably small (large) for total precipitation amount and intensity (frequency, respectively) in both winter and summer seasons. Also, the diurnal phase variations for individual years relative to the seasonal mean precipitation show the significant interannual variability with dominant periods of 2-5 years for all three elements of precipitation and the slightly decreasing trend in total precipitation amount and intensity. To compare the relative contributions of frequency and intensity to the diurnal and semidiurnal cycles (and their sum) of total precipitation amount, the percentage variance of each cycle of precipitation amount explained by frequency is estimated. The fractional variance accounted for by precipitation intensity is greater than that of frequency for these three cycles. All above analyses suggest that intensity plays a more important role than frequency in the diurnal variations of total precipitation amount.

• 한국항공운항학회지
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• 제29권3호
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• pp.111-116
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• 2021

This study aims to identify the representative factors affecting the air trade between the two countries over the past 20 years, targeting China, Korea's largest trading partner for air transport. In the analysis, the two countries' GDP, GDP per capita, and tariff rates, as well as exchange rates, international oil prices, and FTAs were used as variables. For the analysis method, OLS multiple regression analysis was performed, and each was analyzed by dividing the export amount, import amount, and trade amount. As a result of the analysis, China's GDP and Korea's GDP per capita showed a positive (+) direction, an increase in the exchange rate resulted in an increase in the amount of trade, and an increase in the tariff rate resulted in a decrease in the amount of trade. Whether the FTA was concluded or not acted as a factor in increasing the amount of trade between the two countries.

• 한국식품영양학회지
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• 제34권3호
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• pp.272-288
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• 2021

Mealworm is the most widely used edible insect in Korean traditional food. In this study, the quality characteristics and antioxidant activity of Garaedduk containing different proportions of powdered mealworm (0%, 3%, 6%, 9%, and 12%) were evaluated in order to enhance the utilization of mealworm. The results revealed that moisture content decreased while pH and starch elution increased, with increasing amount of mealworm. Furthermore, the amount of total amino acids, essential amino acids, and non-essential amino acids increased with increasing amount of mealworm. Regarding chromaticity, the L value decreased while the a and b values increased as the amount of mealworm increased. The addition of 6% mealworm showed slight differences in the pore size and surface smoothness as compared to plain Garaedduk. Texture, hardness, chewiness, and gumminess increased, but cohesiveness decreased with increasing amount of mealworm. The preference test evaluating the appearance, flavor, taste, texture, and overall preference showed that 6% mealworm additive group had the highest preference. In addition, antioxidant activity of the newly developed Garaedduk increased with increasing amount of mealworm. In conclusion, Garaedduk enriched with 6% mealworm showed promising results for developing rice cake with improved nutrition and antioxidant activity and excellent overall preference and quality.

• 한국안전학회지
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• 제18권4호
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• pp.92-97
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• 2003

The purpose of this study is heavy metal absorption of recycled PET(poly ethylene terephatalate) NWF(non woven faric). The results of test are summarized as follows; Heavy metal abworption rates in Ni ions were higher then Zn and Cu ions, whereas heavy metal absorption rates by sulfonation times were not different. The heavy metal absorption times have a higher tendency from 60 min to 120 min. There were significant negative correlations among the amount used CSA(Chloro Sulfuric Acid) and the amount of absorption Zn(r = -0.33784, p < 0.05), Cu(r = -0.61177, p < 0.01) ions, whereas correlations between heavy metal absorption rates and sulfonation times were not significant. There were significant positive correlations among the amount of absorption Zn ions and the amount of absorption Ni(r = 96475, p < 0.014), Cu(r = 0.51614, p < 0.01) ions, likewise the positive correlations between the amount of absorption N ions and the amount of absorption Cu(r = 0.54766) ions were significant(p < 0.01).

• 한국치위생학회지
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• 제19권4호
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• pp.515-524
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• 2019

Objectives: This study aimed to investigate the effects of the amount and duration of smoking on gingival symptoms in adolescents. Methods: We used the web-based survey data of youth health behaviors from 2016 conducted by the Korean Centers for Disease Control and Prevention. The subjects of the study were 67,983 middle and high school students. Data analysis was performed using the SPSS Ver 20.0 program, and complex sample multivariate logistic regression analysis was performed to analyze gingival symptoms according to short- or long-term smoking habits. Results: In subjects with short-term smoking habits, there was no significant difference in gingival symptoms according to the smoking amount. However, after adjusting for socioeconomic characteristics and oral health behaviors in subjects with long-term smoking habits, a heavy smoking amount (${\geq}0.52PY$) had a 1.25 times higher effect than a light smoking amount (<0.52 PY) on gingival symptoms. Long-term heavy smoking (${\geq}0.52PY$) and low daily tooth-brushing frequency in high school students were factors affecting gingival symptoms. Conclusions: When conducting a project on the oral health of adolescents, it is argued that specific investigations and measures should be set up regarding health behavior factors, such as the amount and duration of smoking among adolescents.

• 한국건설순환자원학회논문집
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• 제8권4호
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• pp.429-435
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• 2020

본 연구에서는 탄소계 섬유를 이용하여 EMP차페 시멘트 개발을 위해 저 직경 카본섬유 사용량에 따른 시멘트 페이스트의 물리적 특성과 EMP차폐 성능평가를 실시하였다. 사용된 저 직경 카본섬유의 길이는 100㎛의 크기로서 육안으로는 분말형태를 나타내기 때문에 시멘트 혼화재 개념으로 사용하였다. 실험결과 저 직경 카본섬유 시멘트 사용량 대비 5% 사용 하였을시 압축강도 및 EMP차폐에 효과가 있었으며 그 이상의 사용시에는 차폐효과는 증가 하지 않았다. 또한 실험체 두께에 따른 EMP차폐성능 검토 결과 저 직경 카본섬유가 사용되지 않은 Plain은 두께에 따른 차폐율 증가 효과가 없었으나 저 직경 카본섬유가 사용된 실험체들은 두께 증가에 따라 차폐성능이 증가 하였다. 따라서 저 직경 카본섬유 사용량과 실험체 두께에 따른 성능을 비교평가 하였을시 EMP차폐율 증가시키기 위해서는 저 직경 카본섬유 사용량은 5%가 최적이며 사용량을 증가시키는 것보다 두께를 증가시키는 방법이 효과적일 것으로 사료된다.

• 한국정보시스템학회지:정보시스템연구
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• 제9권1호
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• pp.129-155
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• 2000

This study empirically examined the relationship between the level of advanced manufacturing technology (AMT) and the information amount of management accounting, such as nonperiodic and future information, and nonfinancial performance. We also investigated the effects of the fit between AMT and accounting informations on the performance of management accounting-information systems (MAS). In this study, the information satisfaction about MAS is used as the surrogate of MAS performance. The results show that the information amount of management accounting is positively associated with the stage of AMT. It is also proved that the information amount of MAS which matches with the level of AMT increases the information satisfaction. However, the information amount that is not compatible with the stage of AMT can not contribute to the improvement of information satisfaction.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회 논문집
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• pp.260-264
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• 2005

Effective use of water resources has become a social problem because the deficit of water comes from population growth and Industrial development. Therefore, the conjunctive operation of surface water and groundwater will become an alternative. Groundwater has many advantages for the evaporation and effect of rainfall compared with surface water. Although the available amount of groundwater is small, groundwater dam can be used complementarily because of the sustainable supply of water. A calculating technique of the optimal amount of water resources by the groundwater dam was developed. A pilot site was selected to assess the optial amount of groungwater for the designed groungwater dam. If the developed technique is more refined by the measured data, the groundwater dam will become a good alternative to develope the water resources in the water deficit area.

• 한국표면공학회지
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• 제4권1호
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• pp.16-23
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• 1971

In this study , fluoborte solution consisting of lead fluoborate, tin fluoborate and cupric acetate was used. By addition of small amount of Cu+= ion to the solution, the Cu content of deposition layer was almost controlled less than 5%. The amount of Cu in deposition layer was almost constant without any influence of Pb++ & Sn++ in the solution, and the amount of Pb was increased by the increase of total concentration of Pb++ +Sn++ in the solution, and the amount of Pb was increased by the increase of total concentration of Pb++ +Sn++ in the solution . Agitation of plating solution & low current density result in the increase of Cu content. Analyzing of microscopic structures and etching tests of the deposited alloy, it was believed that the alloy had a lamellar structure consisting of copper rich lamellar and lead rich layer.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.273-274
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• 2021

This paper proposes a process to calculate the amount of construction and demolition (C&D) of underground vertical extension methods through considering the characteristics of used construction and demolished materials. The underground vertical extension methods analyzed in this paper were the bottom-up, normal top-down, and top-down methods with multi-post downward (MPD). In order to check the applicability of the proposed process, 24 illustrative examples were generated. The amount of C&D waste of the illustrative examples were calculated and compared. As the results, the top-down method with MPD was the most efficient method to reduce the amount of C&D waste.