The conditions for minimizing dyes and additives when dyeing cellulose fibers such as linen, ramie, and hemp fabrics were obtained using glucose, an organic reducing agent. Dyeability and colorfastness were measured through repeated dyeing. The overall surface dyeing concentration followed the linen>hemp>ramie order, and most of the colors were in the range of PB (PurpleBlue). As the glucose concentration increased, the blue series was strengthened, and the color was dark and clear. It was determined that glucose the concentration of 4g/L was appropriate for minimizing the amount of dye. When the dyeing temperature was 30℃, the surface dyeing concentration was the highest, and the color was dark and clear. Although the dyeing concentration increased as NaOH concentration increased, 3g/L (pH 12.37) was considered appropriate for the minimum NaOH concentration, which becomes gradual after the dyeing concentration increased rapidly. It was found that the surface dyeing concentration, when repeated six times for 5 min, was better than that of dyeing once for 30 min. Washing, rubbing, and perspiration colorfastness were all found to be excellent in grades 4–4-5, and colorfastness to light was excellent in grades 5 of linen and hemp and grade 4 of ramie.

In this study, natural dyeing using Polygonum tinctoria was performed with linen, ramie, and hemp, which are biodegradable cellulose fibers, considering environmental aspects. In particular, the impacts of alkali NaOH and reducing agent Na2S2O4 were examined, and the possibilities of minimizing the use and reusing the dye were explored. The surface dye concentrations were found to be in the following order: hemp>linen>ramie. With the increase in all additives, the L* value decreased, and the ⊿E and K/S values increased gradually. When Na2S2O4 was 1g/L, the surface color of the dye appeared uniformly from the NaOH concentration of 0.4g/L (pH 10.84). When NaOH was 0.4g/L, the K/S values of linen and ramie increased rapidly after 0.4g/L of Na2S2O4, and hemp maintained a stable color from 0.6g/L of Na2S2O4. With the increase in the dye concentration from 1 to 6g/L, all the fibers were dyed uniformly. The K/S value increased or higher doubled upon repeated dyeing six times for 5 min than when dyed only once for 30 min. Therefore, the linen, ramie, and hemp fibers dyed repeatedly exhibited good washing, rubbing, and colorfastness to perspiration, which was rated between 4 and 4–5, and that to light was rated as 5. Moreover, no discoloration due to sunlight was observed. Finally, linen exhibited a bacterial reduction of 99.9%, thereby indicating its excellent antibacterial property.

전통염색지인 아청지(감지 : 쪽물 염색지)의 재현을 위해 고문헌 감지의 색상을 조사한 후 인도 쪽 분말과 전통니람법에 의해 제조한 염색한지의 염색특성을 검토한 결과는 다음과 같다. 인도산 쪽 분말로 제조한 염액으로 1회 염색한 경우 염색시간이 증가함에 따라 염착량과 색차 모두 증가하였으 며, 특히 염색시간 15분까지는 급격히 증가하였으나 이후 85분까지는 매우 완만하였다. 그러나 2회차에는 염색시간이 5분에서 40분까지는 색차나 염착량 모두 1회때 보다 약간 높거나 거의 같았으나, 40분 이후에는 오히려 감소하였다. 따라서 염색시간은 15분~30분 정도가 적정할 것으로 생각된다. 전통니람을 전통발효에 의해 얻은 쪽물로 반복염색(1회: 15분 염색, 15분 발색)하면서 염색횟수에 따른 색상을 비교한 결과, 1회의 염색에서의 색상은 1.9G로 그레이톤이었으나, 염색횟수가 증가함에 따라 색상도 G→BG→B→PB로 변화하며 색차와 염착량 모두 증가하여 고문서 감지의 색상인 PB는 8회의 염색한지에서 나타났다. 고문서 감지의 색차, 염착량 및 색상과 비슷한 염색횟수는 30번째로 색차 9.82, 염착량 8.56, 색상 6.0PB였다. 그러나 염색횟수는 염액의 인디고 함량에 크게 좌우되며, 인디고 함량이 높으면 염색횟수는 단축 가능할 것으로 생각된다.

Background: Shoulder external rotation exercises are commonly used to improve the stabilizing ability of the infraspinatus. However, during exercise, excessive activation of the posterior deltoid compared to the infraspinatus causes the humeral head to move anteriorly in an abnormal position. Many researchers have emphasized selective activation of the infraspinatus during shoulder external rotation exercise. Objects: This study aims to delineate the optimal exercise method for selective activation of infraspinatus by investigating the muscle activities of the infraspinatus and posterior deltoid according to the four shoulder exercise methods and two forearm positions. Methods: Thirty healthy individuals participated in this study. The participants were instructed to perform shoulder external rotation exercises following four exercise methods: sitting external rotation (SIER); standing external rotation at 90° abduction (STER); prone external rotation at 90° abduction (PRER); side-lying external rotation (SLER), and two forearm positions (neutral, supinated). The electromyography (EMG) signal amplitude was measured during each exercise. Surface EMG signals were recorded from the posterior deltoid, infraspinatus, and biceps brachii. Results: EMG results of the infraspinatus and posterior deltoid in PRER, were significantly higher than that of the other exercises (p < 0.01). The EMG ratio (infraspinatus/posterior deltoid) in SIER was significantly higher than that of the other exercises. EMG activation of the posterior deltoid in SIER, PRER, and SLER was significantly higher in neutral than in supinated (p < 0.01). Furthermore, the EMG of the infraspinatus in SIER was significantly higher in neutral than in supinated (p < 0.01). The EMG ratio (infraspinatus/ posterior deltoid) in SIER was significantly higher in neutral than in supinated (p < 0.05.) Contrarily EMG ratios in PRER and SLER were significantly higher in supinated than in neutral (p < 0.05). Conclusion: The results show that clinicians should consider these exercise methods and forearm positions when planning shoulder external rotation exercises for optimal shoulder rehabilitation.

Background: Backward walking exercise may offer some unique and potentially beneficial differences compared with forward walking exercise. There is still a lack of research on backward walking exercises and forward head posture. Objects: The purpose of this study was to determine the effect of backward walking exercise on college students forward head posture in their 20s. Methods: Twenty-one subjects participated in the experiment. The subjects were those with a craniovertebral angle (CVA) of 55 degrees or less who understood the purpose and method of this study and voluntarily agreed. A camera capable of taking pictures of the lateral plane was installed at a distance of 1.5 meters before exercising. Pictures were taken before walking backward, and after walking for 15 minutes on the treadmill, the images were taken in the same way. The composition of the backward walking exercise was walking at a rate of 1.0 for 5 minutes, and the remaining 10 minutes were walking at a rate of 1.5. Wilcoxon signed rank test was used to compare CVA and craniorotational angle (CRA) before and after exercise. Results: As a result of this study, there was a significant difference in CVA before and after exercise (p < 0.05). There was a significant difference in CRA before and after exercise (p < 0.05). Conclusion: The backward walking exercise and verbal command seems to have positively influenced the changes in CVA and CRA among college students in their 20s. It seems that studies to confirm balance or muscle activity as well as changes in forward head posture through the long-term intervention of the backward walking exercise should be conducted.

Background: The characteristics of lateral epicondylitis (LE) are muscle strength weakness and increased common extensor tendon (CET) thickness. Ultrasonography has recently been used to evaluate tendinopathy. Diamond taping (DT) is commonly used to manage patients with LE. However, no previous studies have investigated the effects of DT on CET thickness. Objects: The aim of this study was to investigate the effects of DT applied around the lateral elbow on CET thickness, grip strength, and wrist extension force in healthy subjects. Methods: The subjects were 26 adults (13 male) in their twenties. First, the CET thickness was measured at rest. The CET thickness was measured by using ultrasonography at two points. The subjects were then instructed to perform maximal grip activities or maximal wrist extension activities before and after DT around the lateral elbow. The DT technique was applied using non-elastic tape. While the subjects performed maximal grip activities, the investigator measured the maximum grip strength (MGS) and CET thickness. Likewise, while the subjects performed maximal wrist extension activities, the investigator measured the maximum wrist extension force (MWEF) and CET thickness. Results: The MGS showed a statistically significant improvement after DT taping application in men (p < 0.05). The MWEF showed a statistically significant improvement after DT application in male (p < 0.01) and female (p < 0.05). When performing the activities, the CET thickness increased compared to that at rest. However, CET thickness didn’t show a statistically significant improvement before and after DT. Conclusion: This study shows that DT applied around the lateral elbow is effective in improving MGS and MWEF. However, it does not affect CET thickness.

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우리는 오리온 분자운 복합체의 북부 필라멘트(이하 NF)에 대하여 12CO (J=1-0) 분자선의 자료를 이용하여 은하 평면이 분자의 운동과 운동학에 미치는 영향을 연구하였다. 6 m 서울대학교 전파망원경(Seoul Radio Astronomy Observatory, SRAO)을 이용하여 2arcmin 공간분해능으로 은하면으로부터 먼 순서로 NF1, NF2, NF3 세 곳을 총 270시간 동안 관측된 자료를 사용하였다. 은하면과 OMC NF는 12CO (J=2-1) 경우 3% 밀도에서, 티끌의 경우 9% 밝기 수준에서 자기장을 따라 서로 연결되어 있었다. 12CO (J=1-0), 12CO (J=2-1), 성간 티끌 관측결과를 비교해본 결과, 세 경우 모두 NF3에서는 고루 분포했지만, NF1과 NF2에서는 비교적 밀도가 높은 특정 영역에서만 함께 나타났다. NF는 단일 구조를 보였으며, NF1에서는 부분 수축 운동을, NF2에서는 하단에서 회전 운동이 나타났고, NF3에서는 유일하게 명확히 자기장에 연관된 나선형 회전이 보였다. 위치-속도 분석 결과, 12CO (J=1-0)를 비롯한 물질들은 NF2와 NF3을 따라 은하면을 향하여 흐를 가능성이 있음을 확인할 수 있었다. 은하면을 향하여 물질이 흐르는 명백한 원인을 이번 연구결과에서 볼 수 없었지만 추후의 더 정교한 관측결과가 NF1과 NF2 상단부의 회전 운동을 확인 할 수 있겠다.

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본 연구는 친환경적이고 감성적인 패션상품의 색채기획을 위한 자료를 제공하고자 수행되었다. 쪽과 괴화로 복합 염색 후 무매염 견직물과 4종의 매염제(Al, Cu, Fe, Zn)를 처리한 견직물에 대하여 색채특성을 측정하였다. 또한 복합염색 후 매염처리된 연두색 견직물에 대하여 여대생을 대상으로 색채감성과 색채 선호도를 조사하였으며, 색채 특성과 색채감성이 색채 선호도에 미치는 영향을 분석하였다. 쪽/괴화로 복합염색된(무매염) 견직물은 선 염색한 쪽 농도가 10 g/ℓ이면 녹색, 쪽 20 g/ℓ을 사용하면 청록색을 나타내었으며, 4종의 매염제를 사용하여 처리시 거의 모든 경우 연두색을 나타내었다. 연두색을 나타내는 복합염색된 견직물 10종의 색채감성을 요인분석한 결과, 유쾌성, 품위성, 편안성 요인으로 분류되었으며, 이러한 색채감성은 쪽 농도와 매염제의 종류에 따라 대부분 유의한 차이를 보였다. 또한 복합염색된 연두색 견직물의 색채특성과 색채감성요인 간에는 대부분 유의한 상관성을 보여, L＊값, b＊값, C＊값이 크고 a＊값이 작을수록 유쾌성과 편안성 감성을 더 강하게 느끼며, L＊값이 작고 a＊값이 클수록 품위성 감성을 더욱 느끼는 것으로 나타났다. 따라서 쪽과 괴화로 복합염색하고 매염처리한 연두색 견직물의 색채감성요인을 예측변수로 활용할 수 있는 색채 선호도 예측 회귀식이 제안되었다.

본 연구에서는 인체 친화적이고 환경 친화적인 패션제품 소재기획을 위한 기초 자료를 제시하고자 수행되었다. 이를 위해서 4종의 섬유소 소재를 대상으로 염색조건을 달리하여 천연 쪽 염색을 실시하여 색채특성과 색채감성을 평가하였으며, 이러한 특성이 선호도에 미치는 영향을 분석하였다. 쪽 염색된 직물은 모두 중, 저명도와 저채도의 남색(PB)을 구현하였다. 이들 직물의 색채특성은 섬유종류와 염색조건에 따라 유의한 차이를 보였다. 쪽 염색된 직물에 대한 색채감성은 스포티 감성, 클래식 감성, 내추럴 감성 등 3가지 요인으로 분류되었다. 이러한 색채감성은 섬유종류와 염색조건에 따라 부분적으로 유의한 차이를 나타내었다. 또한 쪽 염색 직물의 색채특성과 색채감성 요인 간에는 부분적으로 유의한 상관관계를 보였다. 쪽 염색 직물의 색채 선호도에 영향을 주는 요인으로는 색채감성 요인 중에서 클래식 감성과 스포티 감성, 색채특성에서는 L*값인 것으로 나타났다.

This study investigates characteristics on inelastic flange local buckling of ultra high performance concrete (UHPC) plate supported by one edge. The UHPC plate were modeled using 3D shell elements (S4R) and analyzed using by geometric and material nonlinear analysis. The plates for FE analysis were supported by pined and fixed boundary conditions to considering constrained effects of one web. The inelastic local buckling strength from the FE analysis were evaluated according to the flange slenderness ratios. The results shows that material non-linearities of tensile behavior of UHPC highly affects the inelastic local buckling of UHPC plate.

This study was carried out in order to provide useful data for planning fabrics of summer eco-friendly fashion products. The fabrics used in this study were four cellulose fibers: cotton, cotton/mulberry blended, flax, and flax/lyocell blended. Dyeing with natural indigo was carried out under three different reducing conditions (i.e., general, eclectic, and eco-friendly) that have different reducing agent and pH levels, and hydrosulfite and glucose were used as a reducing agent. The dye uptake (K/S value) of fabrics dyed with natural indigo by a reducing condition was the highest at 660nm. Regardless of the fabrics, dye uptake was the highest under the general reducing condition and the lowest under the eco-friendly reducing condition. Under different reducing conditions, the dye uptake of natural indigo fabrics with the maximum absorption wavelength indicated a difference. The colorfastness of cellulose fabrics that were dyed with natural indigo had a rate of 4 to 5 except for rubbing fastness, which indicated good colorfastness. Additionally, natural indigo-dyed cotton and flax fabrics had good antibiosis. When the color characteristics of fabrics dyed with natural indigo were measured, all of the three reducing conditions created purple blue (PB) colors, and the color characteristics of dyed fabrics by reducing condition and fabric showed significant differences.