• Journal of the Korea Computer Graphics Society
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• v.25 no.1
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• pp.1-11
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• 2019

More force must be applied when dragging a wet compared with a dry cloth lying on the table. Increased force is needed because the fluid between the cloth and the surface of the table produces an adhesion force. In this paper, we study the adhesion force between a wet cloth and the surface of an object. To compute the adhesion force, we used the adhesion force model used in textile research based on real-world experiments and also considered the effect of wrinkles, which, to our knowledge, has not been investigated in previous work. Furthermore, we studied the phenomenon in which a wet cloth adheres to the surface of an object and that in which a wet cloth adheres to itself when undergoing self-collision.

• Applied Microscopy
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• v.52
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• pp.6.1-6.5
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• 2022

We examined the morphology of the fertilized egg and the fine structure of fertilized egg envelopes of Poropanchax normani belonging to the family Poeciliidae, also known as Norman's lampeye using light and electron microscopes. The fertilized eggs with narrow perivitelline space were found to be spherical and demersal, additionally containing small oil droplets in the vitelline membrane. Further, a bundle of adhesive filaments was observed to be present on one side of the fertilized egg. These filaments possessed remarkably high elasticity and were approximately 1-3mm in length. The size of the fertilized egg was determined to be about 1.49 ± 0.07mm (n=30). The outer surface appeared smooth, and adhesive filaments originating at different location of the surface of the envelope were found to be distributed around the egg envelope and were joined together to form a single long bundle in scanning electron microscopic observation. A peak-like structure formed of several straight wrinkles was observed around the micropyle. However, the complete structure of the micropyle could not be studied due to the depth at which it was located. Additionally, the total thickness of the egg envelope was ascertained to be approximately12.5-14.5㎛. The egg envelope consisted of two distinct layers, an outer electron dense layer and an inner lamellar layer, further consisting of 10 sublayers of varying thicknesses. Collectively, it was observed that the morphological characteristics of the fertilized egg, fine structures surrounding the micropyle, outer surface, adhesive structure consisting adhesive filaments, and sections of fertilized egg envelope displayed species specificity.

• Fashion & Textile Research Journal
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• v.18 no.5
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• pp.695-707
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• 2016

This study presents quantitative evaluation standards for the shape fitness test, conducted in the process of the slacks fit test. This study aims to quantify appearance sensory test of slacks for the objectification of qualitative evaluation methods in existing shape fitness tests. The subjects were women of standard body type between the ages of 18 and 24. Slacks differing in their ease in waist girth, hip girth, crotch length and knee length were designed to test their shape fitness. The gap volume distribution between the body and slack, angle of the baseline by body part, and ratio of total thickness from the sideline using 3D human body scan data (which reflect the results of the appearance sensory test) were presented as quantitative evaluation standards. There were less wrinkles in the wrinkle/overstretch and ease categories of the appearance sensory test; in addition, ease was adequate and small enough to comfortably perform basic human activities in the standing upright posture. The gap volume distribution analysis between body and slacks showed that curves increased in the slacks surface along with an increase of ease in slacks and suggested that wrinkles also increased. In the baseline's horizontal categories in terms of a $0^{\circ}$ horizontal angle, the range of angles were evaluated as adequate by the clothing expert group. The total thickness ratio of 0.5:0.5 divides into the sideline from the baseline.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.3
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• pp.695-699
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• 2009

UV irradiation causes skin-aging involving coarse wrinkles, thickening, dyspigmentation, and rough skin surface. This study was carried out to develop health & functional food by using Korean red ginsneg and Fagopyrum esculentum extract mixture (RGFE) for prevention of skin wrinkles. The RGFE-treated group showed the more effective collagenase inhibition rate than the red ginseng (RG)-treated group. To investigate photo protective effects of RGFE on UV-induced damaged skin, SKH hairless male mice were orally administerd RGFE and regional treatment and irradiated with UV for up to 8 weeks. In RGFE-treated group, better skin, and less wrinkle formation were observed compared with UV group. Epidermal thickness of hairless mouse was significantly decreased in RGFE, RG, and Fagopyrum esculentum (FE) groups compared with UV group. These results demonstrate RGFE have photo-protective effects on UV-damaged hairless mouse skin.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.30 no.3 s.47
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• pp.385-388
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• 2004

Recently, along with the remarkable increase in interest in natural products, the application of phytoestrogens in anti-aging products has become very important. In the focus, we developed Pueraria mirifica (PM), in this in vivo study on skin elasticity and wrinkles, and investigated the anti-aging properties. Thirty healthy women volunteers, between the ages of 30 and 60, applied the cream formula with $4\% Pueraria mirifica or placebo, on the face area twice a day for 16 weeks. The evaluation was made by silicon replica analysis, Cutometer SEM 575 and Comeometer followed by statistical treatment using the student's t-test. Results of skin elasticity measurement showed that topical application on the skin increased the total surface of skin elasticity in comparison with placebo group (p<0.05). However, PM cream does not have prominent effect on the depth of wrinkles and skin moisturization. This in vivo study demonstrates that, PM exhibits a significant effect on skin elasticity therefore, is of great interest in anti-aging and firmness skin care products.

• Biomolecules & Therapeutics
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• v.31 no.6
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• pp.640-647
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• 2023

The skin, the largest organ in the body, undergoes age-related changes influenced by both intrinsic and extrinsic factors. The primary external factor is photoaging which causes hyperpigmentation, uneven skin surface, deep wrinkles, and markedly enlarged capillaries. In the human dermis, it decreases fibroblast function, resulting in a lack of collagen structure and also decreases keratinocyte function, which compromises the strength of the protective barrier. In this study, we found that treatment with γ-aminobutyric acid (GABA) had no toxicity to skin fibroblasts and GABA enhanced their migration ability, which can accelerate skin wound healing. UVB radiation was found to significantly induce the production of matrix metalloproteinase 1 (MMP-1), but treatment with GABA resulted in the inhibition of MMP-1 production. We also investigated the enhancement of filaggrin and aquaporin 3 in keratinocytes after treatment with GABA, showing that GABA can effectively improve skin moisturization. In vivo experiments showed that oral administration of GABA significantly improved skin wrinkles and epidermal thickness. After the intake of GABA, there was a significant decrease observed in the increase of skin thickness measured by calipers and erythema. Additionally, the decrease in skin moisture and elasticity in hairless mice exposed to UVB radiation was also significantly restored. Overall, this study demonstrates the potential of GABA as functional food material for improving skin aging and moisturizing.

• Applied Microscopy
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• v.40 no.4
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• pp.245-251
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• 2010

In this study, we applied 15% glycolic acid peeling agent and 30% glycolic acid peeling agent to the dorsal skin of mice and analyzed the oil content, moisture content, and pH value of the skin before and after test using cutometer. Ultrastructure for changes in the epidermis of mice were observed under a dermoscope and a scanning electron microscope before and after test. When using 15% glycolic acid peeling agent, the changes of moisture content was measured 74.67 AU for the normal control group and 70.21 AU for the experimental group, the oil content was 13.49 mg/$cm^2$ for the normal control group before test and 8.25 mg/$cm^2$ after test, and the pH value was 6.70 and 5.36 before and after test, respectively. When using 30% glycolic acid peeling agent, the moisture content was measured 74.46 AU for the normal control group before test and 53.50 AU for the experimental group after test, the oil content was 13.82mg/$cm^2$ and 5.70 mg/$cm^2$ before and after test, and the pH value was 6.45 and 4.58 before and after test, respectively. As such, it was found that the changes of moisture and oil content on the skin rely on the concentration of peeling agent and the degree of exfoliation of keratin. The surface of stratum corneum of mice with application of 15% glycolic acid peeling agent was relatively smooth and the exposed cellular surface of keratinocyte had some wrinkles. The surface of stratum corneum of mice with application of 30% glycolic acid peeling agent was smooth. No wrinkles were observed under high-resolution scanning electron microscope.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.98-98
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• 2010

Ion beam irradiation has been extensively used for surface modification of polymers, glassy metals and amorphous and crystalline materials at micron and submicron scales. The surface structures created by exposure to an ion beam range from dots, steps and one-dimensional straight wrinkles to highly complex hierarchical undulations and ripples. In general, the morphology of these nanoscale features can be selected by controlling the ion beam parameters (e.g. fluence and acceleration voltage), making ion beam irradiation a promising method for the surface engineering of materials. In the work, we presented that ion beam irradiation results in creation of a peculiar nanoscale dimple-like structure on the surface of polyimide - a common polymer in electronics, large scale structures, automobile industry, and biomedical applications. The role of broad Ar ion beam on the morphology of the structural features was investigated and insights into the mechanisms of formation of these nanoscale features were provided. Moreover, a systematic experimental study was performed to quantify the role of ion beam treatment time, and thus the morphology, on the coefficient of friction of polyimide surfaces covered by nanostructure using a tribo-experiment. Nano-indentation experiment were performed on the ion beam treated surfaces which shows that the hardness as well as the elastic modulus of the polyimide surface increased with increase of Ar ion beam treatment time. The increased of hardness of polyimide have been explained in terms of surface structure as well as morphology changes induced by Ar ion beam treatment.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.118-121
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• 2008

Flexible die is more efficacious than fixed die which is generally used in stretch forming process in view of production cost. Accordingly, in order to verily the validity of the flexible forming process, curved thin skin structure forming analyses using the fixed and flexible die were performed. As results, merit and demerit with regard to the fixed and flexible die were confirmed. The result of the stretch forming process analysis using the flexible die was better than that using the fixed die in view of the elastic recovery. However wrinkles were occurred on the sheet material due to die cavities between the punches in the flexible forming process, thus the solutions against these problems were presented.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.6
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• pp.1193-1202
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• 1996

This study investigates and analyzes the amount and shape of the front waist dart of the bodice and investigates the dart division method by bust size. Measurements at 5 arm positions were taken from 15 subjects. Clothing tests were given to 6 of the subjects. The conclusions were as follows: 1) Front Body surface changes were occurred around armpit and they were caused by the wrinkles of the armpit 2) The curved dart line was more appropriate for use with C cup, the large bust body, than the linear line. The changes of the dart amount at arm movements had different types by bust size. 3) Patterns for A & C cup body were adequate to divide the dart amount by 3 darts such as under the B.P., under the anterior armpit and side line, or to aggregate to 1 dart under the B.P. For the B cup body, however, the suitable pattern to use was the total dart amount divided by 1~2 darts and decreasing the waist line at the side line should be avoided.