• Bulletin of the Korean Chemical Society
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• 제24권3호
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• pp.377-383
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• 2003

Physicochemical properties of a series of PC monolayers with different alkyl chains (C24, C20, C16, and C8), at the air/water interface were investigated. The surface pressure is influenced mainly by the hydrophobicity of the PCs, which is confirmed by the curve shape and the on-set value of π-A isotherms at the air/water interface by increasing the number of alkyl chain. The on-set values of surface pressure were 125 Ų/molecule for DOPC(C8), 87 Ų/molecule for DPPC(C16), 75 Ų/molecule for DAPC(C20), and 55 Ų/molecule for DLPC(C24), respectively. The orientations of alkyl chains at the air/water interface are closely connected with the rigidity of the monolayers, and it was confirmed by the tendency of monolayer thickness in ellipsometry data. The temperature dependence of a series of PCs shows that the surface pressure decreases by increasing temperature, because the longer the alkyl chain length, the larger the hydrophobic interaction in surface pressure. The temperature effects and the conformational changes of unsaturated and saturated PCs were confirmed by the computer simulation study of the cis-trans transition with POPC and DPPC(C16). The cistrans conformational energy difference of POPC is 62.06 kcal/mol and that of DPPC(C16) is 6.75 kcal/mol. Due to the high conformational energy barrier of POPC, phase transition of POPC is limited in comparison with DPPC(C16).

• 원예과학기술지
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• 제29권6호
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• pp.555-560
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• 2011

$GA_3$에 의한 화아수 증진효과는 산호수 1년생, 생장조절제의 종류 및 농도에 따른 착과, 비대 및 착색 증진효과는 산호수 2년생을 사용하여 본 실험을 수행하였다. 그 결과, 화아수는 $400mg{\cdot}L^{-1}$ 처리구에서 가장 많았으며, 이는 대조구보다 약 1.8배 많이 형성되었다. 착과율 증진을 위해 산호수 만개시기에 생장조절제를 처리한 결과, $GA_3$와 auxin처리구의 착과율이 증진되었으며, 이 중 $GA_3$가 더 효과적이었다. $GA_3$에 의한 착과율은 0.5와 $1.0mg{\cdot}L^{-1}$ 처리시 각각 약 70%와 77%로 대조구보다 약 1.8배 증가되었다. 또한 Auxin 중 Dichloprop triethanol amine도 약 7-12%가 향상되었지만, cytokinin과 anti-GA는 효과가 없었다. $GA_3$에 의한 산호수 열매 비대효과를 알아보기 위해 만개 2달 후 열매 지름이 약 2-3mm되었을 때 0.3, 0.6, $1.2mg{\cdot}L^{-1}$를 1달 간격으로 3회 처리한 결과, $0.6mg{\cdot}L^{-1}$에서 약 15% 향상되었다. 그러나, 과피의 안토시아닌 측정에 의한 착색정도는 $GA_3$ 처리농도에 따라 유의한 차이가 없었다. 즉, 산호수에 있어서 $GA_3$는 화아수, 착과, 열매 비대를 증진시키는데 효과적인 것으로 나타났다.

• 한국식품조리과학회지
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• 제27권4호
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• pp.27-34
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• 2011

The function of mulberry leaves and the quality of muffins including mulberry leaves were examined. The electron donating ability of both a water and ethanol extract was 40% for both at 100 ppm, 62 and 72% at 500 ppm, and 77 and 83% at 1,000 ppm respectively. These experiments showed good oxidized substance activity. The SOD-like ability of the water and ethanol extracts at 1,000, 500, and 300 ppm was 49% and 55%, 33% and 39%, and 28% and 33% respectively. These results show that the ethanol extract had higher SOD-like ability than that of the water extract. The nitrite scavenging abilities of 1,000 ppm of the mulberry leaf water extract and ethanol extract at pHs of 1.2 and 3.0 were 40.5 and 47%, and 20 and 22% respectively. The Hunter lightness value tended to be lower as the amount of added mulberry leaves increased compared to the contrast set, so the lightness level with a 7% addition was the lowest. The contrast set was the highest for redness and added mulberry leaves tended to decrease redness at 3% but tended to increase it again with additions >3%. The b-value (yellowness) showed a similar tendency as redness. Adding Mulberry leaves tended to decrease the contrast set to the lowest level, then values increased slowly to a peak at 5% added mulberry leaf and then decreased thereafter. Strength and hardness were less after increasing added mulberry leaf. Cohesiveness, springiness, gumminess and brittleness, decreased at up to 5% added mulberry leaves but the 7% addition showed the same level as the contrast set. The mulberry leaves muffins were less preferred to the contrast set in appearance and color. However, the mulberry leaf muffins were preferred to the contrast set in taste and flavor but the result was not significant. Overall the quality of the muffins with 3% added mulberry leaves was preferred over the 1% added mulberry leaf muffins.

• 한국ITS학회 논문지
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• 제8권5호
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• pp.57-70
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• 2009

교통여건의 변화로 좌 우회전, 중앙버스 및 자전거 전용신호에 대한 요구가 증대되고 있다. 그러나 현재 운영되고 있는 표준규격 교통신호제어기는 4색등화기를 기반으로 하고 있어, 3색등화기의 방향별 차종별 전용신호를 운영하는 데 제약이 있다. 따라서 본 연구는 기존 표준 교통신호제어기에서 좌 우회전 및 중앙버스의 전용신호를 제어할 수 있는 물리적 소프트웨어적인 방안을 제시하였다. 물리적으로 보행 적, 보행 녹, 적, 황, 화살표 및 녹색등화의 6개 출력단자로 설계된 4색등화기의 신호등구동장치(LSU)를 적, 황, 녹색의 3개 씩 2단 배열로 그룹화 하여, 3색등화기의 전용신호로 사용하는 방안을 제시하였다. 소프트웨어적으로 신호 맵 데이터의 코드값을 3색등화기의 적1 황1 녹1 적2 황2 녹색2의 LSU 출력에 맞게 설정하여, 링별(A/B링) LSU별로 전용신호를 스텝별로 구동하는 방안을 제안하였다. 전용신호 도입 시의 운영효과를 중앙버스전용차로가 운영되고, 좌회전이 허용되는 서울시 망우역교차로를 대상으로 분석한 결과 버스전용차로가 운영되고 있는 주도로(동-서)에서 지체가 크게 개선되어 교차로 전체의 지체시간이 70초/대 이상 개선되는 것으로 분석되었다.

• 한국염색가공학회지
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• 제22권2호
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• pp.173-179
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• 2010

In this study, we determine the stretch and shrinkage properties of conjugated yarns. The shrinkage(%) and elasticity(%) were determined by applying twist conditions of 0, 350, 800, 1000, 1200, 1400, 1600, 2000 T/M (twisting per meter). It is found that the shrinkage(%) and elasticity(%) gradually decreased with increasing T/M. Especially the elasticity(%) dramatically decreased over 1400 T/M condition. In contrast, it is showed that the handle and drapery properties decreased below 1000 T/M, which indicates that the optimal T/M condition could be 1000~1400. The effect of shrinkage(%) and elasticity(%) with different steam setting temperatures (60, 70, 80 and $90^{\circ}C$) was also determined. The shrinkage(%) decreased with increasing setting temperature, while the elasticity not changed. In this context, the optimal steam setting temperature could be $80^{\circ}C$ because it is not easy to weave with the yarns which was set below $80^{\circ}C$. The elasticity(%) decreased with increasing the density of warp and weft. To produce soft handle, excellent drapery and good stretch fabrics, the warp density needs to be reached by 90% of the ideal warp density. In the case of NaOH treatments to the fabrics, the elasticity(%) increased with increasing weight reduction. Therefore, this study have demonstrated that the conjugated yarns with core yarn and the SDY CD(cation dyeable spindraw yarn) as an effect yarn would be appropriate to produce excellent mixture-yarn, which displays clean appearance, good handle and excellent elasticity, The optimized conditions are as follows; 1000~1200 twist per meter, $80^{\circ}C$ steam setting temperature, 90% of ideal warp density and relaxation condition treated with 5g/l NaOH concentration.

• 한국운동역학회지
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• 제25권3호
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• pp.363-370
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• 2015

Objective : The purpose of this study was to give the basic data for the cutting movement with the various angels on the poly urethane. Method : Ten healthy men voluntarily participated in this study. A three-dimensional motion analysis system (VICON) and force plates were used to analyze the movements of the joints for the lower extremities. For the statistical analysis the IBM SPSS 21.0 was used to perform repeated measured ANOVA and post-hoc comparison result was used to perform the Scheffe and the level of significance was set up at ${\alpha}=.05$. Results : There were significant differences for the time required for the increasing angles of the cutting movement(p<.05). In addition, there were significant differences for the maximum dorsiflexion, plantarflexion of ankle joint, maximum flexion of knee joint and hip joint with the increasing the angles of cutting movement(p<.05). Also, there were significant differences for the maximum adduction and abduction angle of the hip joint with the increasing of the angles of cutting movement. There was signigicant difference for the resultant utilized coefficient of friction(RuCOF) for the increasing angles of cutting movement(p<.05). Conclusion : There was a pattern to increase the coefficient friction with the angle of cutting direction. Also, it would be possible to use the poly urethane for the outdoor floor with the results of this study.

• 한국주조공학회지
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• 제25권4호
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• pp.168-172
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• 2005

In this study, the effects of chill layers occurred in shot sleeve on the molten metal filling were analyzed through computer simulation and the behavior of chill layers with temperature variation of shot sleeve set from 200 to $280^{\circ}C$ was also investigated. The simulation results showed the chill layers set in the in-gates during the injection process change the main filling direction and cause turbulent flow pattern, resulting in porosities inside the castings. The amount of chill layers with the increasing temperature of shot sleeve was considerably reduced. And particularly, at the setting temperature of $280^{\circ}C$ by heat control unit, the big reduction in chill layers, excellent trimmed surface and the highest densification were achieved, suggesting that as the optimal sleeve condition in diecasting, especially for the highly complex parts like valve body.

• 정보저장시스템학회논문집
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• 제8권2호
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• pp.39-43
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• 2012

In spite of many advantages, the practical application of the thin film solar cell is restricted due to its low efficiency compared with the bulk type solar cells. This study intends to adopt the surface plasmon effect using nano particles to solve the low efficiency problem in thin film solar cells. By inserting Ag nano-particles in the absorbing layer of a thin film solar cell, the poynting vector value of the absorbing layer is increased due to the strong energy field. Increasing the value may give thin film solar cells chance to absorb more energy from the incident beam so that the efficiency of the thin film solar cell can be improved. In this work, we have designed the optimal shape of Ag nano-particle in the absorbing laser of a basic type thin film solar cell using the finite element analysis commercial package COMSOL. Design parameters are set to the particle diameter and the distance between each Ag nano-particle and by changing those parameters using the full factorial design variable set-up, we can determine optimal design of Ag nano-particles for maximizing the poynting vector value in the absorbing layer.

• 전기전자학회논문지
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• 제9권2호
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• pp.143-151
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• 2005

본 연구에서는 유한고장 비동질적인 포아송 과정 모형에서 결함당 고장 발생률이 상수이거나, 단조 증가 또는 단조 감소하는 패턴을 가질수 있다. 감마족 분포를 적용하여 고장발생률에 대한 특징을 알아보았고 감마족 분포는 형상 모수의 선택에 따라 다양한 모형으로 유도 될 수 있다. 따라서 본 연구는 형상모형에 근거한 감마 또는 와이블 그리고 곰페르츠 모형을 제시하여 신뢰도 분석 결과를 나열하였고 모형 선택 및 자료 분석을 위하여 산술과 라플라스 검정과 편차 자승합 등을 이용하였다.

• 한국의류학회지
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• 제44권4호
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• pp.626-638
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• 2020

In this study, protective masks were designed in varying internal volume and analyzed in regards to wearing effect. Masks were measured by surface temperature and subjective wear evaluation. Four experimental masks were created with an increasing distance between the mask center line and nose in increments. The distances were set at 0.0 cm (M0), 2.0 cm (M2), 4.0 cm (M4), and 6.0 cm (M6). The area and volume of each experimental mask was measured and both measurements had a positive correlation with the set distances. Among the experimental masks, M2 was the most breathable. The heat between the face and the mask created by exhalation was able to escape from the mask and provided the highest comfort sensation when worn. Conversely, an internal volume that is too large would decrease its comfort because repetitive breathing deforms the appearance of the mask and adversely affects its fit. Therefore, creating and maintaining the optimal internal volume of the M2 mask is important to achieve maximum thermal sensation and ease of wear.