• 한국항공우주학회지
• /
• 제38권5호
• /
• pp.421-426
• /
• 2010

본 논문에서는 코너에서 대각선방향으로 인장하중을 받고 있는 접힌자국이 있는 사각형 멤브레인에서 두께가 주름 거동에 미치는 영향을 기하학적 비선형 후좌굴 유한요소해석을 통하여 연구하였다. 멤브레인은 쉘 요소로 모델링 하였고 좌굴을 발생시키기 위하여 면외방향으로 미소의 무작위성 기하학적 결함을 메쉬에 가하였다. 해석은 접히지 않은 원멤브레인과 수직방향으로 접힌 멤브레인에 대해 수행하였고 그 결과를 비교하였다. 해석결과 멤브레인의 두께가 감소함에 따라 주름의 발생과 성장을 크게 촉진함을 알 수 있었다. 또한 접힌 자국의 초기 전개각이 증가할수록 국부주름의 낮은 하중에서 발생하였으나 전역주름으로의 성장은 지연되는 경향을 보였다.

• 한방안이비인후피부과학회지
• /
• 제24권2호
• /
• pp.68-78
• /
• 2011

Objective : The purpose of this clinical research was to investigate the effects of herbal cosmetics containing Momordica charntia L. extracts on the anti-wrinkle and whitening effects. Methods : A total of 25 subjects who visited Daegu Hanny Oriental Medical Center from November 1st, 2010 to December 31th, 2010 were included in this study. In this study, we observed change of R1, R2, R3, R4, R5 for using products, change of average melanin content and pigmental area, analysis results of subjective wrinkle improvement, Analysis results of subjective whitening improvement. Statistical analysis was performed by using paired t-test and wilcoxon signed ranks test. Statistical significance was achieved if the probability was less than 5%(p<0.05) Results : Statistically, herbal cosmetics containing Momordica charntia L. extracts showed siginificant effect on change of R1, R2, R3, R4, R5 for using products, change of average melanin content and pigmental area, analysis results of subjective wrinkle improvement, Analysis results of subjective whitening improvement(p<0.05). And satisfaction after using herbal cosmetics was near good. Conclusions : Considering the above results, we have concluded that herbal cosmetics containing Momordica charntia L. extracts have the remarkable effects on the anti-wrinkle and whitening effects.

• 한국소성가공학회:학술대회논문집
• /
• 한국소성가공학회 2004년도 제5회 압연심포지엄 신 시장 개척을 위한 압연기술
• /
• pp.307-316
• /
• 2004

This study examined the cause of the wrinkle defect which is frequently encountered in wire rod rolling of low carbon steel$(C0.08\~0.13wt.\%)$. Even a small defect on the surface of rolled bars can easily develop into fatal cracks during cold heading process of low carbon steel, and it is therefore necessary to minimize inherent defects on the surface of hot rolled bars. Hot rolling process of low carbon steel was analyzed to identify the cause of the wrinkle defect in conjunction with FE analysis. The integrated analysis revealed that the wrinkle defect initiated in the first stage of rolling, and it was at the billet edge where severe deformation and drastic temperature drop were present. To elucidate the micro-mechanical mechanism of the wrinkle defect, hot compression tests were carried out at various temperatures and strain rates using Gleeble-3800. The surface profile of the each other compressed specimens was compared, and rough surface lines were observed at relatively low temperatures. Those surface defects can develop into wrinkles during multi-pass rolling. To control the wrinkle defect in rolling, it is necessary to design an adequate caliber which can minimize the loss of ductility, and thereby prevent flow localization. To use the result of this study fur other steels, the quantitative measure of the wrinkle defect and flow localization parameter should be proposed.

• Fibers and Polymers
• /
• 제2권4호
• /
• pp.190-195
• /
• 2001

Additives, such as sodium perborate and borax, were examined in dialdehyde wrinkle resistant finishing of cotton. Results indicated that the whiteness index(WI) of cotton treated with dialdehyde and additive showed about 90% of WI of the untreated cotton but with decrease in wrinkle recovery angle (WRA) due to inhibition effect of these additives. Effect of additive on the WRA reduction was more prominent with glutaraldehyde than with glyoxal. Reduction in WRA of cotton treated with both dialdehydes and boron compound was minimized by simultaneous addition of formic acid in the bath. Addition of formic acid was also generally beneficial in maintaining WI retentions after 8 months storage. Furthermore, boron compounds were also effective in improving retentions of mechanical properties. By FTIR analysis the residual aldehyde group was detected on the dialdehyde-finished cotton, whereas no peak was shown by addition of boron compounds. This suggested that the residual aldehyde group was a main cause of fabric yellowing on the dialdehyde-finished cotton. Dialhehyde with boron compound, therefore, can be used to replace a conventional formaldehyde-containing wrinkle resistant finishing of cotton.

• Korean Journal of Acupuncture
• /
• 제38권2호
• /
• pp.62-74
• /
• 2021

Objectives : The aim of this study is to analyze the effect of acupuncture and the details of acupuncture treatment methods on skin wrinkles. Methods : Search was conducted in Pubmed, KISS, and NDSL databases for acupuncture studies on skin wrinkles. The detailed therapeutic techniques of acupuncture used for skin wrinkles and the effect of acupuncture on skin wrinkle improvement were analyzed. Then, the study results using the same indicator were compared through meta-analysis in order to compare the effects of acupuncture with the control group. The quality of randomized controlled trials (RCTs) was assessed using the risk of bias (ROB) assessment tool (Ver. 1.0, Cochrane Collaboration). Results : A total of 10 RCTs and 19 case series were included in this study. The most frequently used therapeutic technique for skin wrinkle improvement was Microneedle therapy system (MTS, n=19), and they were mostly used with aesthetic solutions (13 out of 19 studies). Skin wrinkle related indexes were most commonly used to evaluate skin wrinkle improvement (n=14). Panax Ginseng pharmacopuncture showed the most remarkable effect in improving the range of skin wrinkles and the depth of skin wrinkles. MTS+epidermal growth factor improved the levels of skin hydration, skin elasticity, and variation of skin pigment the most. MTS+Endothelial precursor cell improved the number of skin melanin the most. Three RCTs included in the meta-analysis showed moderate ROB on average. Conclusions : Acupuncture treatment was effective in improving skin wrinkles. However, a precise study design using unified indicators and appropriate controls needs to be performed in further studies in order to establish more convincing evidence of the effectiveness of acupuncture for improving skin wrinkles.

• 한국약용작물학회지
• /
• 제19권6호
• /
• pp.508-513
• /
• 2011

The bark of the root and stem of Ulmus davidiana var. japonica has been used as a traditional Korean medicine to treat inflammatory disorders. This plant reportedly shows antioxidant, anticancer, and anti-inflammatory effects. In this study, we investigated the protective effects of Ulmus davidiana var. japonica ethanolic extract (UDE) on UVB irradiation-induced wrinkle in hairless mice. We evaluated for their free radical-scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and the anti-elastase activities, and for their anti-matrix metalloproteinase-1 (MMP-1) activity in human skin fibroblast cells. In the wrinkle measurement and image analysis of skin replicas, the results showed that UDE significantly inhibited wrinkle formation caused by chronic UVB irradiation. These results suggest that UDE has anti-wrinkle activity.

• Toxicological Research
• /
• 제30권4호
• /
• pp.283-289
• /
• 2014

Tea flavonoids and polyphenols are well known for their extraordinary antioxidant activity which is considered important for anti-aging processes in animals. This study evaluated the anti-wrinkle effects of three different kinds of tea (Camellia sinensis) water extracts (CSWEs) including green, white, and black teas using a photoaged hairless mouse model. Data showed that the CSWE-treatment greatly improved skin conditions of mice suffering from UVB-induced photoaging, based on the parameters including the skin erythema index, moisture capacity, and transepidermal water loss. In addition, the wrinkle measurement and image analysis of skin replicas indicated that CSWEs remarkably inhibited wrinkle formation. In histological examination, the CSWE-treated mice exhibited diminished epidermal thickness and increased collagen and elastic fiber content, key signatures for skin restoration. Furthermore, the reduced expression of MMP-3, a collagen-degradative enzyme, was observed in the skin of CSWE-treated animals. Interestingly, comparative data between green, white, and black tea indicated that the anti-wrinkle activity of white tea and black tea is equally greater than that of green tea. Taken together, these data clearly demonstrated that CSWEs could be used as an effective anti-wrinkle agent in photoaged animal skin, implying their extended uses in therapeutics.

• 한국의류학회지
• /
• 제31권2호
• /
• pp.217-224
• /
• 2007

This paper investigated spring/summer fabric trends of women's and analyzed the correlation between the fabric trends and finishing for 10 years (1995 S/S-2004 S/S). Fabric trend terms were selected from 5 fashion journals and were grouped by hierarchical cluster analysis using SPSS 12.0 statistical package. Also, finishing terms were selected and analyzed by frequency. The results showed that 13 representative fabric trend terms were clean, functional, lustrous, compact, rubbery, comfortable, chic, romantic, decorative, natural, fluid, textured, and ethnic trend. In terms of fabric finishing, 12 representative finishing were selected such as coating, calendaring, wrinkle finishing, decorative finishing, quilting, and washing. Finally, in respect of the analysis of fabric trends and finishing, washing and embroidery were used to represent ethnic trends and textured fabric was closely correlated wrinkle and decorative finishing. Fluid fabrics were expressed via wrinkle and coating and washing and wrinkle were used for natural feeling. Decorative fabric was expressed by embroidery and coating and decorative finishing were frequently used to show romantic and chic fabric. Also comfortable fabrics were correlated with easy care and rubbery, compact, lustrous, and clean fabrics were correlated with coating.

• 한국항공우주학회지
• /
• 제36권9호
• /
• pp.851-858
• /
• 2008

본 논문에서는 수직방향으로 접은 사각형 멤브레인의 주름 거동을 기하학적 비선형 후좌굴 해석을 사용하여 연구하였다. 멤브레인은 쉘 요소로 모델링 하였고 하중은 멤브레인의 코너에서 대각선 방향으로 가하였다. 해석에는 다양한 각도의 초기 전개각을 가지는 멤브레인을 고려하였고 접힌 자국이 없는 경우에 대해서도 해석을 수행하여 그 결과를 비교하였다. 해석결과 주름은 큰 코너하중이 가해진 지역에서 국부적으로 발생하였는데, 이 국부 주름은 하중 비의 증가에 따라 점차 성장하여 전역 주름으로 발전하였다. 또한 주름의 발생 및 성장 거동은 접힌 자국의 초기 전개각에 좌우되는 경향을 보였다.

• 한국소음진동공학회논문집
• /
• 제22권12호
• /
• pp.1157-1163
• /
• 2012

Natural frequency of a nano-resonator via nano transfer printing is studied. Through a nano transfer printing, the hybrid metal/polymer membrane may evolve a wrinkle. Natural frequency of a wrinkled hybrid membrane decreases significantly, as the amplitude to wavelength ratio becomes larger. To address the design limit of a hybrid nano resonator, we perform parametric study using finite element analysis. Specifically, we study the effects of the Young's modulus ratio of the metal/polymer membrane, thickness ratio and wrinkle amplitude to wavelength ratio, respectively. The results from the parametric studies can serve as guideline to design hybrid nano resonators.