• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.1D
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• pp.7-15
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• 2011

The travel time value is important factor for the evaluation of feasibility the transportation facility investment. The existing method for calculation of the travel time for each mode uses daily average trip purpose. So the value of travel time is constant because it is estimated with only daily average proportion. This daily constant time value can distort the results of future demands of toll roads or economic appraisals for the projects. The proportion of the trip purpose varies by time periods. Accordingly the value of travel time also varies by time periods. In this study, times periods are classified as morning peak, evening peak, business time off-peak, and non-business time off-peak. And trip purpose proportions are sorted by each time period from raw data of Seoul household trip study, then the value of travel time for each time period is estimated with these sorted purpose proportions. A case study of Seoul Jung-gu and Yongsan-gu performed with newly estimated time value by time periods. The result of benefit calculation with the daily constant time value is overestimated approximately annual 2.5 billion Won compared by time values by time periods. The demands of toll roads are also overestimated with the existing daily constant time value by daily 3,500 vehicles and total revenue of toll roads are overestimated by annually 1 billion Won. In conclusion, the value of travel time by each time period enables the more precise economic evaluation of the transportation facility investment projects, mode choice behavior, and route choice behavior especially for toll roads.

• The Journal of the Korea Contents Association
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• v.13 no.11
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• pp.829-844
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• 2013

This study performed comprehensive tests on the four hypotheses on the capital structures for the firms listed in the KOSPI during the period from 2006 to 2011. It may be of concern to find any financial profiles on firms' leverage across the book- and market-value bases since there was relatively little attention drawn to any financial changing profile of the leverage surrounding the period of the pre-and the post-global financial crises. The findings of this study may also be compared with those of the previous related literature, by which it may be expected to enhance the robustness and consistency of the results across the different classifications on capital markets. It was found that three explanatory variables such as PFT, SIZE, and RISK, were found to be the statistically significant attributes on leverage during the tested period. Moreover, the outcome by the Fisher Exact test showed that a firm belonging to each corresponding industry may possess its reversion tendency towards the industry mean and median leverage ratios.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.9
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• pp.466-472
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• 2020

The purpose of this study is to explore how to use location data for peer relations of infants in free-choice play activities. For this study, location data was collected using wearable devices for 14 students in one class at an early childhood education institution in Chungnam. For the pre-processing of the collected location data, a smoothing technique was applied to recover missing values during the collection process, and the data was visualized using Python's Matplotlib. Subsequently, the movement distance, distance between infants, and interaction types of infants were extracted from the location data using the formula. As a result of the study, it was possible to derive 1) change in moving distance, cumulative value, average value, 2) change in distance and average distance value between infants, and 3) change and trend in interaction type according to the passage of time. These results can provide valuable information on the process of forming peer groups for infants in situations where it is difficult for a teacher to closely observe all members, and can be used as meaningful information for the design and operation of educational programs.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 1998.11a
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• pp.158-162
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• 1998

향에 의해 유발되는 감성에 대한 중추신경계 및 자율신경계의 반응의 변화를 측정하기 위해 안정시키는 향과 각성시키는 향을 사용하여 주관적 평가와 동시에 시행하였다. 안정시키는 향으로 1% Lavendar 향을 사용하였고, 각성시키는 향으로 0.8% Jasmin 향을 사용하였으며, 안정상태를 향자극 전후에 측정하여 대조군으로 사용하였다. 중추신경계의 지표로 뇌파측정을 하였고 뇌파의 전극은 international 10-20 system에서 4 채널을 사용하였으며, 자율신경계의 지표로는 심전도, heart rate, 피부저항, 피부온도를 기록하였다. 뇌파의 분석은 Fast Fourier Transform analysis의 power spectra로 하였고, 그 frequency bands는 theta(4-8Hz), alpha(8-l3Hz), beta(14-30Hz)로 하였다 또한 심전도를 이용하여 심전도 상의 연속적인 R-R peak간 시간간격을 시계열 데이터로 재구성한 Heart rate variability 분석도 하였다. HRV 분석을 보다 정확히 할 수 있도록 호흡이 심전도에 미치는 영향을 제거하기 위하여 호흡을 분당 20회로 일정하게 하였다 생체신호 측정과 동시에 실시한 주관적 검사에서 lavendar 향은 친숙하게, jasmin 향은 활기차고 상쾌하고 유쾌하게 평가되었다. 뇌파 분석에서 lavendar 향을 주었을 때 theta의 증가 양상을 보였으며, Jasmin 향을 주었을 때는 모든 채널에서 beta 파의 증가 양상을 보였다. 또한 HRV 분석 결과 부교삼신경의 활동성이 부각되는 HF/LF의 값이 lavendar에서는 대조 자극보다 높게 나타났으며, jasmin에서는 대조자극보다 낮은 값이 나타나는 경향을 보였다. 결론적으로 안정과 각성의 후각 자극으로 인한 감성의 변화를 뇌파와 자율신경계 등의 생체지표로 관찰할 수 있었다.정하는 감성요인의 차이를 알 수 있었으며 또한 essential oil에서는 성별 차이가 없는데 반해 페르몬 향의 경우 성별의 차이를 나타내었다.. 방법을 타액과 혈청내 testosterone 농도 측정에 응용하여 RIA의 결과와 비교하여 본 바 상관관계가 타액에서 r=0.969, 혈청에서 r=0.990으로 두 결과가 잘 일치하였다. 본 실험에서 측정된 한국인 여성의 타액내 testosterone농도는 107.7$\pm$12.0 pmol／l이었고, 남성의 타액내 농도는 274.2$\pm$22.1 pmol／l이었다. 이상의 결과로 보아 본 연구에서 정립된 EIA 방법은 RIA를 대신하여 소규모의 실험실에서도 활용할 수 있을 것으로 사려된다.또한 상실기 이후 배아에서 합성되며, 발생시기에 따라 그 영향이 다르고 팽창과 부화에 관여하는 것으로 사료된다. 더욱이, 조선의 ${\ulcorner}$구성교육${\lrcorner}$이 조선총독부의 관리하에서 실행되었다는 것을, 당시의 사범학교를 중심으로 한 교육조직을 기술한 문헌에 의해 규명시켰다.nd of letter design which represents -natural objects and was popular at the time of Yukjo Dynasty, and there are some documents of that period left both in Japan and Korea. "Hyojedo" in Korea is supposed to have been influenced by the letter design. Asite- is also considered to have been "Japanese Letter Jobcheso." Therefore, the purpose of this study is to loo

• The Korean Journal of Food And Nutrition
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• v.14 no.5
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• pp.391-396
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• 2001

Effects of substitution of stevioside and maltitol with sugar on the quality characteristics of pound cake and butter cooky were investigated. Pound cakes increased in baking loss rates and decreased in water contents with substitution of sugar by stevioside and malitol. The yellow values of interior of pound cakes, and the lightness and yellow values of surface of butter cookies significantly decreased with substitution of sugar by stevioside and maltitol. Most of texture parameters such as hardness, chewiness, springiness, cohesiveness and gumminess of pound cakes, and hardness and brittleness of butter cookies also decreased with substitution sugar by stevioside and maltitol. In sensory evaluation, texture and appearances of pound cakes containing stevioside and maltitol were positively different compared to that of sugar control. However, butter cookies containing stevioside and maltitol were negatively different in texture and positively different In appearance compared to that of sugar control. Taste, flavor, sweetness and overall acceptability of pound cakes and butter cookies were not different between sugar and stevioside group. In conclusion, textures and appearances of pound cakes might be improvable without affection on other characteristics, and butter cookies were almost the same as the results of Pound cakes except deterioration of appearance, when sugar were substituted with stevioside and maltitol.

• The Journal of the Petrological Society of Korea
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• v.16 no.2 s.48
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• pp.59-72
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• 2007

Kilauea volcano located in the southern part of Hawaii island chains has been formed by continuous and sporadic eruption activities from 16 century to September of 1982. Kilauea volcano was investigated from collecting the samples of basalt to identify the geochemical characteristics of the lavas. Olivine, clinopyroxene, plagioclase, and opaque minerals with glass groundmass are observed. Clinopyroxene formed glomerophopyritic texture with plagioclase and zoning texture was observed in some of plagioclase phenocrysts. Major elements such as $K_2O$, $P_2O_5$, $TiO_2$ increased with respect to MgO. $Al_2O_3$ and CaO show the kink on Marker diagram due to the crystal fractionation of plagioclase and clinopyroxene with plagioclase respectively. Olivine has a wide range of Fo% ranging from 60 to 90, and MnO and FeO in the olivine are decreased with increasing Fo% oppositely increased $SiO_2$, MgO, and NiO. Ni in the whole rock is controlled not only by the mode of olivine but also by the Ni abondance in the olivine.

• Proceedings of the Korea Water Resources Association Conference
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• 1996.01a
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• pp.1-95
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• 1996

전국에 산재한 수위관측지점의 관측개시 이후의 모든 홍수위 자료를 구성하고 주요 지점의 개별 홍수사상에 대한 단위도를 유도하여 지점별 대표단위도를 작성하였다. 또한 유도된 대표단위도를 이용하여 미계측 지점에 대한 단위도와 첨두홍수량을 추정하였다. 연구 결과를 요약하면 다음과 같다. 1991년과 1992년에 이어서 1993년에도 홍수위자료의 수집과 정리에 역점을 두어 관업을 수행하였으며 조선하천조사서, 조선하천조사연보, 한국수문조사연보 등의 각종 문헌에 수록되어 있는 주요 홍수사상의 수문곡선을 판독하여 전국 220개의 수위관측지점에 대하여 총 5,735개 사상의 홍수위 자료를 구축하였으며 이를 자료집으로 구성하였다. 홍수사상에 대한 단위도를 유도하기 위하여 시우량자료는 기상청 자료를 중심으로 구성하였으며 효율적이고 안정적인 능형회귀방법을 이용한 단위도 유도 방법을 적용하여 사용자가 화면을 통해서 홍수사상과 유도된 1mm-1hr 단위도를 보고 적합한 단위도를 선택할 수 있도록 단위도 유도 프로그램을 개발하였다. 대부분의 홍수사상이 지정홍수위 이상인 범위만이 정리되었는데 지정홍수위 이하의 부분은 일수위로부터 읽은 값을 참고로 하고 대수보간을 하여 자료를 구성하도록 하였다. 개발된 단위도 유도 프로그램을 사용하여 지점별 홍수사상별로 단위도를 유도하여 유역별로 총 65개 지점에 대하여 952개의 단위도를 유도하였는데 한강 유역은 16개 지점에서 263개의 단위도를 유도하였고 낙동강 유역은 28개 지점에 460개 단위도를, 금강 유역은 7개 지점 82개 단위도를, 영산강 유역은 7개 지점에서 88개 단위도를, 섬진강 유역은 7개 지점에서 59개의 단위도를 유도하였다. 유도된 단위도들을 지점별로 평균하고, 이를 참고로 하여 Nash 모형을 이용한 지점별 대표단위도를 유도하여 정리하였다. 또한 유도된 대표단위도를 유역에 따라서 지점별로 비교하여 상하류간의 관계를 분석하였으며 신뢰할만한 결과로 판단되었다. 유도된 대표단위도의 첨두유량 및 첨두시간을 유역면적 등과 비교하여 그 관계를 검토하였다. 유역면적과 첨두유량 및 유역면적과 첨두시간의 관계는 비교적 일정한 경향을 보여주었으며 이를 이용하여 미계측 유역의 1mm-1hr 단위도를 추정하였다. 2년 빈도의 설계강우량에 대해서 유역면적이 50, 100, 1,000, 10,000, 20,000$\textrm{km}^2$인 경우 첨두홍수를 추정하였으며 유출률을 0.9로 할 때 4장에서 분석, 제시된 지점별 평균연최대홍수와 비슷한 값을 보여주었다. 따라서 미계측 유역에서는 설계강우량만 주어진다면 본 연구에서 추정된 미계측 유역의 단위도 추정 방법을 이용하여 첨두홍수를 추정할 수 있을 것으로 판단된다. 본 연구의 단위도 유도 대상 지점은 전국의 수위관측지점이었으나 5대강을 제외한 기타 수계에 있어서는 수위자료뿐만 아니라 유량측정성과도 미비하여 단위도 유도를 하지 못하였다. 또한 유역면적 500$\textrm{km}^2$ 이하에서는 홍수위 자료는 있어도 유량측정성과가 없는 지점이 많았고 육량측정성과가 수 회에 불과한 지점이 대부분이었기 때문에 단위도를 유도할 수 없었다. 따라서 분석된 결과를 소유역으로 연장하는 것은 다소 무리가 따르며 대략 어느 정도가 될 것이라는 참고자료로 이용하는 것이 바람직하다고 본다. 현재의 여건에서는 소유역의 유량측정성과를 확충하는 일이 급선무일 것이다. 유역면적이 작은 수위 관측 지점에 대한 지속적인 유량측정이 절실히 요구된다.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.4
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• pp.380-388
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• 2023

This study estimates the metacentric height (GM) of a model ship by varying the transverse weight distribution, considering the effects of the roll period and moment of inertia, and compares it with the GM values measured by the inclining test. In the process, the relationship between the values is analyzed. Three types of ships-a 7-ton fishing vessel, 20-ton fishing vessel, and KRISO Very Large Crude-oil Carrier (KVLCC)-were used for the experiment and comparison. The roll period and moment of inertia were measured using the free roll decay and swing frame tests, and the GM was measured using inclining test. The estimated GM from the roll period and moment of inertia showed the same trend as the GM measured using the inclining test in the change of the weight distribution. However, the GM values measured using the inclining test were lower. Therefore, additional correction factors or parameters other than the roll period and moment of inertia are necessary for estimating GM. In the future, the relationship between the weight center and the estimated GM will be analyzed to derive the correction factors.

• Korean Journal of Food Science and Technology
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• v.45 no.4
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• pp.441-450
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• 2013

The purpose of this study was optimization of the conditions for mixing different amounts of red radish (Raphanus sativus L.) sprout powder, butter, and sugar when baking domestic wheat cookies prepared using red radish sprout powder. Response surface methodology, with a central composite design comprising 5 levels and 3 variables, was used to identify the best possible combination of amounts of red radish sprout powder ($X_1$), butter ($X_2$), and sugar ($X_3$). The physical and mechanical properties of each of the 20 samples analyzed, including color L (p<0.001), color a (p<0.01), color b (p<0.001), spread ratio (p<0.001), and hardness (p<0.01), differed significantly. The results of sensory evaluations, including color (p<0.001), appearance (p<0.001), texture (p<0.001), flavor (p<0.01), taste (p<0.001), and overall quality (p<0.001) also differed significantly among the samples. The optimal compositional ratios were 5.15 g for the red radish sprout powder, 64.84 g for the butter, and 47.18 g for the sugar.

• Journal of Korean Society of societal Security
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• v.1 no.3
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• pp.59-67
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• 2008

The most influential facility causing traffic disaster on the urban road is intersection. Accordingly, this study elected a region for case study from seabang three-way junction, partial section of Dongmoon Ro in Kwang-Ju city, to the intersection of Mudeung Library Entrance. It is believed that the signal progression is very effective on the basis of short interval of intersection and massive traffic volume. The signal progression was simulated by using TRANSYT-7F model. The following is summary of the simulation: According to the change of cycle length, P.I. delay and fuel consumption showed the tendency of being increased in case that cycle length becomes long or short, centering around the best cycle length. In the event of progressing the cycle length, the average speed per vehicle is increased by 11.39Km per hour and P.I value is improved by 40.65% so that it resulted in 42.86% improvement in the total travel time. Moreover, the fuel consumption in line with the progression practice produced fuel saving of 31.04%.