• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2000년도 가을 학술발표회논문집
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• pp.151-158
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• 2000

Cable dome that consists of three component such as cable, strut and fabric membrane has complex structural characteristics. Main structural system of cable dome is cable-strut tensegric system and fabric membrane element is conceived as cladding roof material. One of the important problem of cable dome is to investigate the structural response from external load effect such as snow and wind. When cable dome is subjected to load each structural component has various special structural characteristics. One is that geometrical nonlinearity should be considered because large deformation is occurred from their flexible characteristic. The other is that wrinkling occurs occasionally because cable and membrane elements can not transmit compressive forces. So this paper researches the physical structural response of cable dome structure and the structural behavior when failure occurred at a part of structure.

• 약학회지
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• 제47권6호
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• pp.398-403
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• 2003

To investigate the relationship between structure and biological activity of phenylpropanoids, we measured effects of phenylpropanoids on anti-oxidant and whitening activity, In DPPH radical scavenging activity, caffeic acid analogues showed the significant anti-oxidant activity. Although phenylpropanoids did not inhibit purified-tyrosinase activity, they significantly inhibited tyrosinase activity and melanin production in MSH-stimulated B16 melanoma cells. However, phenylpropanoids did not affect tyrosinase expression in MSH-stimulated B16 melanoma cells, which suggest that inhibition of MSH-induced melanin production was due to tyrosinase inhibition mediated via other signal pathways but not expression of tyrosinase. Phenylpropanoids also significantly inhibited both hyaluronidase and elastase activity, suggesting that phenylpropanoids may be used as whitening, hydration and anti-wrinkling agents. Hydroxyl residue of aromatic ring in phenylpropanoids plays an important role in anti-oxidant and whitening activity.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2007년도 Proceedings of The Convention
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• pp.140-152
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• 2007

Hyaluronic acid(HA) is a naturally occurring mucopolysaccharide composed of the repeating disaccharide unit of D-glucuronic acid and N-acetyl-D-glucosamine. HA exists as a high molecular weight polymer in the extracellular matrix of many tissues in the body. HA has been widely used not only for osteoarthritis and ophthalmology but also for cosmetics for skin care. Recently HA has drawin much attention for use in health foods. Bioland Corporation started production of HA t1y biotechnological process in 1990 for cosmetical use. At present Bioland produces HA for cosmetic and food use. We have done many researches to evaluate the helpful effect for skin and safety of HA as food. In order to evaluate the effect of HA on the skin after its oral intake, we measured its bioavailability, skin-care effects on anti-wrinkle, moisturization elasticity and desquamation by clinical trial. The results showed that HA is very safe and could bs helpful to improve anti-wrinkling, moisturization, elasticity, and desquamation on the skin.

• 대한기계학회논문집
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• 제13권5호
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• pp.886-900
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• 1989

본 연구에서는 블랭크홀더력이 디프드로잉 성형성성에 미치는 영향에 대해 알아보고자 윤활조건에 따라 블랭크홀더력의 적정 범위를 이론적으로 파악해 보고, 실험의 경우 고강성 스프링형 블랭크홀더 방식에서 나타나는 디프드로잉 특성 및 초기블랭크홀더력의 성한한계에 관하여 검토하는 것으로 하였다.

• 소성∙가공
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• 제30권5호
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• pp.236-241
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• 2021

This study describes the cold stamping process design procedure to secure the formability and dimensional accuracy of the automotive structural component fabricated by 1.5GPa grade ultra-high strength steel sheet. The target product is selected as the front side rear lower member which is the most important energy absorption part in the frontal impact condition. To secure the product quality, an intermediate product shape is added while considering the low elongation and high strength characteristics of 1470Mart. The sequential optimization procedure of the intermediate product shape, the fine dimensional quality is then achieved without any crack or wrinkling. The cold stamping method with ultra-high strength steel sheets is validated by conducting the die tryout of the front side rear lower member.

• 대한약학회:학술대회논문집
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• 대한약학회 2002년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2
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• pp.392.1-392.1
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• 2002

One of the important functions of skin is protection from harmful environments. There has been many studies for keeping skin healthy from wrinkling and pigmenting. Skin wrinkle and pigmentation could be caused by the disruption of connective tissue, free radicals and ultraviolet irradiation. In this study, the extracts obtained from 25 kinds of medicinal plants were screened. All the extracts examined were obtained by using 70% (v/v) ethanol at $60^{\circ}C$. (omitted)

• Design & Manufacturing
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• 제15권2호
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• pp.17-22
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• 2021

The shape of the blank greatly affects the formability and quality of the product after the stamping process. In this study, the geometry of the B-Pillar blank in the stamping process was optimized using design of experiments. The geometry of the blank for the B-pillar was simplified with the two length values and two radius values. The effects of design variables were studied through the Design of experiments. The stamping process of the B-pillar was predicted with the Finite Element Analysis (FEA). The optimized blank geometry was obtained. It results in the reduced maximum equivalent plastic strain. The local necking and the wrinkling did not occurred with the optimized blank geometry.

• 한국식품영양과학회지
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• 제42권4호
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• pp.505-511
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• 2013

막걸리 제조 시에 발생하는 부산물의 화장품 소재 가능성을 조사하기 위하여 항산화능, 페놀 함량, 코지산 함량, 미백, 주름 개선 효과 등을 분석하였다. 누룩박, 미박, 원주, 시판제품을 5가지 다른 용매(0, 25, 50, 75, 100% 에탄올)로 $20^{\circ}C$와 $50^{\circ}C$에서 각각 추출하였다. 총 페놀 함량은 $20^{\circ}C$에서 추출하였을 때 누룩박의 에탄올 75% 추출물에서 13.26 mg GAE/g으로 가장 높았으며, $50^{\circ}C$에서는 시판 제품의 에탄올 75% 추출물에서 16.66 mg GAE/g으로 가장 높았다. 가장 높은 코지산 함량은 $20^{\circ}C$에서 누룩박의 0% 에탄올 추출물에서 관찰되었고, $50^{\circ}C$에서 추출한 모든 시료에서 코지산은 검출되지 않았다. $20^{\circ}C$에서 제조한 누룩박, 미박 추출물에서 상당한 항산화능(DPPH와 ABTS 라디칼 소거능, 환원력)이 확인되었다. Tyrosinase 저해능으로 분석한 미백 효과는 $50^{\circ}C$에서 누룩박의 75% 에탄올 추출물이 가장 높았다. 누룩박과 미박은 elastase 저해능도 발견되어 주름 개선 효과가 있음을 확인하였으며, 특히 $20^{\circ}C$에서의 미박 추출물이 가장 높은 활성을 나타내었다. 이상의 결과는 막걸리 제조 부산물이 항산화, 미백, 주름 개선의 기능을 가진 화장품 소재로서의 가능성이 있음을 시사한다.

• 한국미생물·생명공학회지
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• 제40권3호
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• pp.208-214
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• 2012

본 연구는 왕겨를 이용한 항산화, 항노화에 효과적인 초액을 대량생산하여 기능성을 검증하고 왕겨초액 내의 기능성물질을 분석하여 사업화의 가능성을 타진하고자 하였다. 정제된 왕겨초액을 분획하여 기능성이 확인된 부분을 HPLC 기기를 이용하여 확인한 결과 caffeic acid 외에 7종의 polyphenol 유래물질에서 기능성을 확인하였다. 기능성 화장품소재 시험으로는 세포 생존율 측정(MTT assay), 주름개선 (collagenase inhibition assay, elastase inhibition assay), 미백(tyrosinase inhibition assay), 항산화 시험(DPPH free radical scavenging assay, SOD-like activity, xanthine oxidase inhibition assay)이 실시하였다. 피부주름형성은 콜라겐의 합성과 분해가 중요한 원인으로 작용한다고 알려져 있지만, 최근 많은 연구에서 엘라스틴의 재형성과 분해 또한 주름형성 기전에서 중요한 작용을 하는 것으로 보고되고 있다. 왕겨초액은 $100{\mu}L/mL$의 농도에서 collagenase 저해효과가 100%, elastase 저해효과가 55% 이상으로 주름개선 효과가 우수하였다. 왕겨초액은 $100{\mu}L/mL$의 농도에서 tyrosine에 대한 tyrosinase 저해효과가 80% 이상으로 미백효과가 우수하게 나타났다. DPPH radical 소거율, xanthine oxidase 저해와 SOD-like 활성을 이용하여 항산화 효과를 측정하였다. 왕겨초액 $100{\mu}L/mL$의 농도에서 DPPH radical 소거율이 80%, xanthine oxidase 저해효과가 80%, 그리고 SOD-like 활성이 100%를 나타내었다. 따라서 본 연구를 통하여 정제 왕겨초액을 이용한 산업화를 위한 가능성을 타진하여 효과가 좋음을 확인할 수 있었다. 이와 같은 결과로 왕겨초액을 이용한 기능성 화장품의 소재로 뿐만 아니라, 식품 및 의약외품의 품목허가를 통하여 고부가가치의 상품화소재로의 가능성이 있다고 사료됩니다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2007년도 춘계학술대회 논문집
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• pp.266-267
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• 2007

Sandwich sheet with inner structure is expected to find many applications because of high stiffness to mass ratio. In order to simulate forming of sandwich sheet with pyramid core, an effective simulation method is required. Compared to the expensive model using solid elements, cost effective model using simplified elements such as shells and beams is developed. By comparing two models in terms of the cost and accuracy for unit cell deformation, a developed model shows some advantages over the model using solid elements. Evolution of two kind of forming limits, face buckling and core buckling are successfully expressed by developed model. Developed model is also applied in the simulation of square cup drawing and L-type bending. The corresponding experiments are carried out. Deformation shape and wrinkling behavior are compared and discussed. It is found that simulation results using a developed model are in good agreement with experiments.