• International Journal of Highway Engineering
• /
• v.9 no.3
• /
• pp.21-28
• /
• 2007

We suggest a new spatial linear interpolation method to substitute linear interpolation method which widely used in transportation engineering to impute the missing daily traffic volume. We layout daily traffic volume which is time series data over the virtual lattice space to consider the spatial correlation. We used Moran Index to evaluate the spatial correlations among daily traffic volume in same week and same date traffic volume by week considering the circularity of daily traffic volume. For real application, we used daily traffic volume on November, 2004 provided by Korea Institute of Construction Technology(KICT) and transformed daily traffic volume to 4 times 7 virtual lattice space to reflect the spatial correlation. Finally we showed that the spatial linear interpolation method has good performance for missing data imputation based on MAPE, RMSE, and Theil's U criteria.

• Proceedings of the Korea Society of Poultry Science Conference
• /
• 2003.11a
• /
• pp.123-124
• /
• 2003

6개의 화학제제를 육계의 깔짚에 첨가한 후 6주간의 사육기간 동안 육계의 생산성, 계사 내의 암모니아 발생량을 측정하여 6개의 화학제제를 대조구와 비교하였다. 본 실험은 A계사와 B계사 각각에 대조구(4케이지)와 시험구(4케이지)를 배치하였으며 대구대학교 동물사육실에서 실시하였다. 시험은 각 방에서 4반복으로 실시하였다. A계사는 화학제제 I (T$_1$)을 깔짚에 첨가하고 나머지는 대조구로 하였다. B계사에는 화학제제II(T$_2$)를 깔짚에 첨가하고 나머지는 대조구로 하였다. 대조구와 실험구는 철저히 막아서 공기가 서로 내통되지 않게 하였다. 화학제제 I (T$_1$)과 II(T$_2$)의 실험이 끝난 후 같은 방법으로 화학제제III(T3)과 IV(T4)도 실시하였으며 계속해서 화학제제V(T$_{5}$)와 Ⅵ(T$_{6}$)이 실시되었다. 총 시험기간은 2002년 10월 31일부터 익년 3월 22일까지 143일간 계속되었다. 6개의 화학제제를 각각 깔짚에 첨가하였을 때 대조구에 비교하여 육계의 생산성에는 아무런 차이가 없었다. 암모니아 가스 농도는 화학제제 I (T$_1$)과 II(T$_2$)의 경우 2주에서 6주까지 처리구와 대조구간의 차이를 나타내었다. 화학제제III(T$_3$)의 처리구는 5주 동안 암모니아 가스발생은 거의 없었으며 대조구와는 큰 차이를 나타냈다. 화학제제IV(T$_4$)와 V(T$_{5}$) 그리고 Ⅵ(T$_{6}$)에서도 처리구와 대조구간에 차이가 인정되었으나 처리IV(T$_4$)와 Ⅵ(T$_{6}$)의 경우는 처리구에서도 5주와 6주의 경우 암모니아 농도는 25 ppm이거나 그 이상을 유지하였다. 모든 처리구에서 계사내 암모니아 가스농도는 25 ppm보다 낮았으나 화학제제III(T$_3$)에서는 계사내의 암모니아 가스 발생량은 거의 0에 가까웠다. 결론적으로 6개의 처리들간의 비교는 할 수 없지만 화학제제III(T$_3$)의 경우에서 처리구는 암모니아 가스 발생량을 다른 처리구에 비교하여 가장 낮게 나타났다.

• Korean Journal of Remote Sensing
• /
• v.22 no.6
• /
• pp.595-600
• /
• 2006

GOCI is the core paryload of the geostationary satellite COMS(Communication, Ocean and Meteological Satellite) for ocean monitoring. It is scheduled to be launched at the end of 2008. GOCI observes ocean color around the Korean Peninsula over $2500km\times2500km$ area. It used tilted two-axis scan mechanism to observe entire field of view. In this work, the pointing stability of the tilted two-axis method is analyzed and compared with that of gimbal method. The analysis results show that tilted two-axis method gives great stability and it is adequate for geostationary payload. The results can also be used to determine and analyze the mechanism specifications.

• Korean Journal of Social Welfare Studies
• /
• v.48 no.2
• /
• pp.303-329
• /
• 2017

This study aimed to explore the trajectories of computer game use of school age children and to identify the related predictors. The data for this study used Korean Children and Youth Panel data covering from the second year to the sixth year of elementary school. A total of 1,959 participants were analyzed. Latent class growth model was employed to explore the trajectories of computer game use and multinomial logistic regression was conducted to identify the significant predictors. Main results indicated that three types of trajectories were identified: low game using group, high initial using-fluctuating group, and high increasing game using group. Each group was found to be associated deferentially with sex, aggression, attention deficit, main caregiver's education, siblings, parent absence after-school, neglecting, family income, family trip, school grades, and peer relationship. Based on these findings, this study emphasized the importance of predictive intervention for the game user among early school age children and suggested useful practical strategies.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2019.05a
• /
• pp.240-244
• /
• 2019

본 연구에서는 2차원 수치모형(Nays2DH)을 적용하여 금강 상류에 건설된 세종보를 중심으로 보 개방 후에 홍수량 변화에 의한 하도의 지형변화 과정을 분석하였다. 수치모의를 위한 홍수량은 금남수위표에서 2018년 1월부터 2018년 12월까지 각 시간별 유량을 일반화(normalizing) 하여 하였다. 부정류 홍수량은 2018년 7월의 홍수량 $3,341m^3/s$을 적용하였으며, 부정류의 첨두유량($3,341m^3/s$)이 발생시간은 28시간이고 유출량은 $108.1m^3/s$으로 설정하였다. 수치모의 시간은 120시간으로 설정하여 사주의 발달, 이동, 사주의 형상 및 하도 지형변화를 분석하였다. 첨두유량은 $2,281m^3/s$, 2차 첨두유량은 $3,515m^3/s$, 3차 첨두유량은 $4,259m^3/s$으로 각각 26시간, 107시간, 200시간 동안 발생하는 부정류를 적용하였다. 수치모의 구간은 세종보를 중심으로 상하류 6.5 km 구간을 설정하였으며, 보는 완전히 개방된 것으로 설정하였다. 단일 홍수가 유입될 때 보다, 3개의 홍수가 연속으로 유입될 때에는 보 상류에서 사주의 크기가 크고, 사주의 수가 증가하며, 저수로의 변화가 다양하였다. 흐름이 집중되는 구간에서 하상은 깊게 세굴 되어 하천구조물의 안정과 주의가 필요하다. 그러나 하도의 다양성과 역동성이 크게 개선되는 특성을 보여주었다. 하상의 종방향 특성을 고려할 때, 세종보 하류에서는 하상고가 상승하는 특성을 보여 주었으나, 하상고가 불규칙한 특성을 보여주었다. 이는 단일홍수에 비해하여 하도의 역동성이 큰 것을 의미한다, 사주의 이동속도는 1차 첨두유량일 때 가장 빠르게 나타났지만, 이후 2차 및 3차의 유량이 더 많았지만 사주의 이동속도가 감소하였다. 보를 완전개방 하였을 때는 흐름이 안정화 되어 이동속도 변동폭이 작아졌다.

• Journal of Adhesion and Interface
• /
• v.4 no.1
• /
• pp.9-17
• /
• 2003

The UV hard coating materials are attracting more and more attention to modern industry, in terms of the development of low or non solvent coating materials which will contribute to economizing both materials and energy and to reducing pollution. This study was performed in order to invent UV curable coating materials containing colloidal silica which have actual industrial applications. As results of experiments, the oligomers type and the concentration of colloidal silica acrylate oligomer (SAOC) have an influence on various especially, The properties of UV hardening cooling, such as chemical, abrasion resistance and weatherability, were greatly enhanced, the impact properties of coated polycarbonate substrate were improved compared with the noncoated that. The UV cured films containing 30 wt% SAOC obtained showed the best properties.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.26 no.1
• /
• pp.41-58
• /
• 2000

Recently the harmfulness of W radiation is in creasing due to encironmental pollution. Environmental population may also play a role in global decrease of ozone layer, A major consequence of ozone depletion is increase in solar ultra violet radiation received at the earth's surface excessive exposure to W radiation cause a lot of problems in our skin. Plant extract that possess antioxidative activities has been reported to retard the oxidation process in product to which they have been added. Plant are alived under solar light. So it is expect the plants have so many protection mechanisms and UV absorbent ingredients against ultra violet radiation such as UVB, UVA. Plant extract which were flavonoids, alkaloids and others could be transformed into UV absorber by chemical modification. Therefore with the aim of finding alternative natural absorber that can safely be used in cosmetic, we have screened various extract for their UV absorbent effect. Thus, the cosmetic safety against human skin, antimicrobial effects and others could be improved by using the silicon.

• The Journal of the Korea Contents Association
• /
• v.21 no.9
• /
• pp.622-631
• /
• 2021

This study was conducted to verify the effects of individual psychological capital, spousal support, and organization's family-friendly work culture on work-life balance in social workers. For this purpose, married social workers working in social welfare facilities in Chungcheongbuk-do were surveyed, and 331 collected responses were used in the analysis. Multiple regression analysis revealed that resilience and optimism in individual psychological capital, spousal support, and expectations on working hours in organizations' family-friendly work culture were significantly associated with the work-life balance. In addition, there were different factors influencing the level of work-life balance according to gender and age. The findings suggest that efforts to enhance awareness and improve working conditions, such as the development of self-care program, education on the necessity of work-life balance, and implementation of work-life balancing system, are needed to improve the work-life balance of social workers.

• Journal of Korean Philosophical Society
• /
• v.147
• /
• pp.77-116
• /
• 2018

The purpose of this paper is to elucidate the late Heidegger's thought through commonality and differences with mystical thought. Heidegger embraces poetic and mystical elements in the process of overcoming traditional metaphysics and cognitive discourse and for exploring new meaning of Being. This study of mystical elements in his thought is important to present the uniqueness of the Heidegger's philosophy. This paper will not deal with mystical experiences or religious meanings, but with philosophical mysticism that reveals the fundamental connection between human and Being through thinking of Being itself. Here in connection with traditional mysticism the following topics will be discussed as mystical elements in the later Heidegger's thought: the Abyss of Being(Ab-grund), which go beyond conceptual reasoning and representational thinking(principle of ground); Lighting of Being(Lichtung), in which human and all Beings can be opened, and the Letting-be(Gelassenheit), which is gained not by any human accomplishment.

• International Area Studies Review
• /
• v.12 no.3
• /
• pp.195-216
• /
• 2008

It is generally accepted that the momentum strategies are effective in the short-term, and the contrarian strategies are profitable in the long run in major stock markets in the world. In Korean market, however, the contrarian is considered effective investment strategy both in the short- and long-term. We investigate whether this is true after 1999, and try to find out the reasons for this phenomena. We found that the contrarian strategies are still effective. Foreign investors showed consistent investment behavior both in Korean and abroad: they followed momentum in the short-tem, and contrarian in the longer-term. The individual investors, who are thought to be noise trader, showed different behavior. They followed contrarian strategies both in the short-and long-term. The reason that the contrarian is observed in Korean market regardless of the investment horizon is thought to be the irrtional behavior of individual investors.