• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.133-142
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• 2014

Recently, more focus is shift to imbalances in aggregate market supply and demand and an exhaustion of natural resources. In this situation, Electric arc furnace oxidizing slag (EAF Slag) has high application possibility as aggregate for concrete due to similar property with general aggregate. In this study, We've got the plan to assure the chemical stability of EAF Slag, and then experimentally tested the mechanical performance and durability for the fine aggregate used EAF Slag. On this test result, we suggest the application plan. At the result of this study, it shows that EAF slag would reduce the surface defect such as pop-out due to natural aging for the fixed hour and adjustment the grain size of EAF Slag. And mechanical performance and durability according to the replacement rate of concrete service, were revealed more than equal or equal compare to general aggregate. Hereafter, quality control must precede not to impede the beauty of concrete surface as assure the safety for aging and processing. And, to establish the environmental resource recycling system for by-products of steel, it should be made development of various application and guideline of quality control for the EAF slag aggregate. Moreover, it must be constantly studied all kind of engineering performance and durability for related to this study.

• The Korean Journal of Applied Statistics
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• v.28 no.4
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• pp.643-661
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• 2015

Korea Teachers Pension (private school pension) is a mandatory pension and a social security system for private school teachers to ensure the stability of subscribers by a supplying pension when they (and their dependents) face future economic risk due to retirement or death. Therefore, the Teachers Pension must provide stability and sustainability in regards to adequacy of income and to function as a pension. However, the Government Employees Pension System (GEPS) of Korea (the most representative special occupation pension) recorded a fiscal deficit in 2001 and with an accumulated deficit that is expected to grow; subsequently, various plans for the reform of GEPS have been actively discussed. The Korea Teachers Pension system is based on the GEPS scheme and is not free from the GEPS discussions on reforms of national pension. The current system for the Teachers Pension needs to be improved because it is expected to be depleted within the next 30 years due to low fertility and an aging population in Korea. This study discusses existing Teachers Pension schemes problems and suggests a projection method and revised plans to improve it. We use long-term financial projections of the Teachers Pension to estimate the fund exhaustion point and the minus balance of the financial scale as well as analyze the supply-demand burden structure that reflects the future population structure to propose Teachers Pension reforms that will improve stability and adequacy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.12
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• pp.5518-5524
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• 2011

The purpose of this study is to investigate the change of balance ability on aging by measuring balance ability of elderly females whose age is over 65. The subjects are ten elderly women (the mean age: 71.9) able to walk without assistants, the assistant equipments and drug dependence and ten young healthy women (the mean age: 23.2). We measured stability index (ST), Fourier index (F), weight distribution (WD), weight distribution index (WDI), synchronization index (SI) and fall index (FI) by using Tetrax (Tetra-ataxiometric Posturography). In result, STs and Fs at the low frequency region (F1) represented the significant difference between two groups at all postures with PO (pillow with eye open) exception (p<.01). Fs at the other frequency regions (F2~F8) represented the significant difference between two groups (p<.05). WDI of the elderly women represented the higher values than the young women at all postures but there are the significant difference at PO and PC (pillow with eye closed) only. These results may be due to age-related ability decline of somatesthesia, vestibular organ, central nervous system.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.2
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• pp.125-131
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• 2018

Ascorbic acid (Vitamin C) has been widely used in skin care formulations. Due to its remarkable effects on anti-oxidation, collagen biosynthesis and whitening, ascorbic acid is considered as an effectible anti-aging active ingredient. But, the instability problems of ascorbic acid in cosmetic formulation such as oxidation, browning and changes in smell is the difficult issue to be overcome for the application of high concentration of ascorbic acid. We tried to stabilize the ascorbic acid in non-aqueous liquid formulation that contains polyol solvent at first. The non-aqueous system was effectible to reduce oxidation. But, ascorbic acid was crystallized in the non-aqueous formulation at the low temperature below $5^{\circ}C$. We tried to develop way to stabilize the ascorbic acid in aqueous solutions to solve the crystallizing problem. In this study, we search the optimal ratio of antioxidant combination, such as zinc sulfate, glutathione and curcuma longa (turmeric) root extract. Formulations were stored at - $16^{\circ}C$, $5^{\circ}C$, $25^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$ and cycle($5-40^{\circ}C$) (in incubator) for a period of eight weeks to investigate their stability. In the stability analysis, the test parameters consisted of color, scent, phase separation and sedimentation. Ascorbic acid stability was checked by HPLC analysis.

• Journal of Computational Design and Engineering
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• v.3 no.3
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• pp.179-190
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• 2016

A kind of modified epoxy resin sheet molding compounds of the impeller has been designed. Through the test, the non-metal impeller has a better environmental aging performance, but must do the waterproof processing design. In order to improve the stability of the impeller vibration design, the influence of uncertainty factors is considered, and a multi-objective robust optimization method is proposed to reduce the weight of the impeller. Firstly, based on the fluid-structure interaction, the analysis model of the impeller vibration is constructed. Secondly, the optimal approximate model of the impeller is constructed by using the Latin hypercube and radial basis function, and the fitting and optimization accuracy of the approximate model is improved by increasing the sample points. Finally, the micro multi-objective genetic algorithm is applied to the robust optimization of approximate model, and the Monte Carlo simulation and Sobol sampling techniques are used for reliability analysis. By comparing the results of the deterministic, different sigma levels and different materials, the multi-objective optimization of the SMC molding impeller can meet the requirements of engineering stability and lightweight. And the effectiveness of the proposed multi-objective robust optimization method is verified by the error analysis. After the SMC molding and the robust optimization of the impeller, the optimized rate reached 42.5%, which greatly improved the economic benefit, and greatly reduce the vibration of the ventilation system.

• Korean Journal of Plant Resources
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• v.21 no.1
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• pp.5-11
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• 2008

This study examined the characteristics of Pinus thunbergii community that forms a windbreak forest around the coast of Gwanmaedo located in Jodo-myeon, Jindo-gun, Jeollanamdo which is located in the south-western areas of Korea from December 2005 to April 2007 and to suggeste the ecological management methods of coastal windbreak areas. P. thunbergii community, a coastal windbreak forest of Gwanmaedo, was classified into disturbance, growth, mixture, stability, and back mountain vegetation according to major companions species and vegetation types. P. thunbergii community of disturbance and growth vegetation needs active management through tree thinning, mowing, weeding out, use of rest space, and felling sick pine trees. P. thunbergii community of mixture, stability, and back mountain vegetation needs active preservation of a coastal windbreak to restore natural vegetation by making a windbreak walk and a forest buffer zone and inducing vegetation succession. Accordingly, in this study, ecological management methods were suggested according to the actual state of distribution by habitat characteristics of coastal windbreak areas such as management of beaches and surrounding area of idle lands, restoration of back wetlands, inhibition of foreign plants, maintenance of diversity of species and habitats, and prevention of aging and spread of damage from insects.

• Fashion & Textile Research Journal
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• v.18 no.6
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• pp.858-868
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• 2016

This study aims to examine the formative characteristics of seniors' fashion in overseas social media, and look into the psychological characteristics of seniors by analyzing the emotions and the characteristics of psychological mechanism in seniors' fashion. The study methods include statistical analysis and content analysis for literary study and data analysis. For data analysis, statistical and content analyses were conducted to analyze 992 data collected from Advanced style, Facebook, and Instagram for 4 years from 2013 to 2016. In formative features shown at overseas social media, circle and square silhouette, achromatic color and warm color, showy tone color, soft material, horizontal details, plain and natural patterns, cap and sunglasses production, and sophisticated elegance styles appeared high. The emotional characteristics in senior's fashion had a silhouette that expressed stability, color that expressed passion, love, happiness, joy, hope and comfort. Materials were expressed by the emotions of dependence and attachment, details were expressed by stable, maternal, calm, comfortable and harmonious emotions. Patterns were expressed by the images of beauty, love, fruit and psychological stability. Accessories were expressed by young and characterful images. Style expressed the emotions of trust, pride, longing, intoxication and ecstasy. The characteristics of psychological mechanism used such shapes and patterns as flower, heart and lips to symbolize the emotions of love, humor, and fun. Young and trendy fashion were expressed in compensation for aging. Kitsch and kidult style was expressed by regression. Elegance fashion was expressed by the sublimation of pride, trust and intoxication.

• Land and Housing Review
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• v.3 no.4
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• pp.379-387
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• 2012

This paper analyzes characteristics and changing phenomenon of Chonsei & monthly rental real estate market based on a survey of participants. The frequency analysis, mean analysis, and cross-table analysis was utilized for this study, and a survey for 2,000 rental market participants was accomplished. The survey result of tenants and land-owners regarding the Chonsei market stability indicates the expansion of public housing supply is needed together with lowering of mortgage related restrictions. The major conclusions include that the expansion of public housing and rental supports for low-income families are needed, due to the population structural change and an aging society. In addition, survey result suggests the tenants require the expansion of public housing supply for the residence stability.

• Macromolecular Research
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• v.17 no.2
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• pp.128-132
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• 2009

Fucoidan, a sulfated polysaccharide derived from brown seaweed, is an important material valued for its various biological functions, including anti-coagulation, anti-aging, and immune system support. In this study, we examined the potential of fucoidan as a novel emulsifying agent in BSA (bovine serum albumin)-stabilized emulsion at a neutral pH. We measured the dispersed oil-droplet size, surface zeta-potential and creaming formation of 0.5 wt% BSA emulsion (20 wt% oil traction) in the absence and presence of fucoidan. The average particle size and zeta-potential value were 625.4 nm and -30.91 mV in only BSA-stabilized emulsion and 745.2 nm and -44.2 mV in 1.0 wt% fucoidan-added BSA emulsion, respectively. This result suggested that some positive charges of the BSA molecules interacted with the negative charges of fucoidan to inhibit the flocculation among the oil droplets. The creaming rate calculated from the backscattering data measured by Turbiscan dramatically decreased in 1.0 wt% fucoidan-added BSA emulsion during storage. Accordingly, the repulsion forces induced among the oil particles coated with 1.0 wt% fucoidan in emulsion solution resulted in significantly increased emulsion stability. The turbidity of the BSA-stabilized emulsion at 500 nm decreased during five days of storage. However, the fucoidan-added BSA emulsion exhibited a higher value of turbidity than the BSA-stabilized emulsion did. In conclusion, an anionic sulfated fucoidan lowered the surface zeta-potential of BSA-coated oil droplets via the electrostatic interaction, and subsequently inhibited the flocculation among the oil droplets, thereby clearly minimizing the creaming and phase separation of the emulsion.

• Molecules and Cells
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• v.38 no.2
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• pp.163-170
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• 2015

Lipoteichoic acid (LTA) is a major component of the cell wall of Gram-positive bacteria. Its effects on living organisms are different from those of lipopolysaccharide (LPS) found in Gram-negative bacteria. LTA contributes to immune regulatory effects including anti-aging. In this study, we showed that LTA isolated from Lactobacillus plantarum (pLTA) inhibited melanogenesis in B16F10 mouse melanoma cells. pLTA reduced the cellular activity of tyrosinase and the expression of tyrosinase family members in a dose-dependent manner. The expression of microphthalmia- associated transcription factor (MITF), a key factor in the synthesis of melanin, was also decreased by pLTA. Further, we showed that pLTA activated melanogenesis signaling, such as extracellular signal-regulated kinase (ERK) and phosphatidylinositol 3-kinse (PI3K)/AKT. In addition, the expression of heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1) and HuR, which are important RNA-binding proteins (RBPs), was reduced. pLTA likely degrades MITF via regulation of melanogenic signaling and RNA stability of melanogenic proteins, resulting in the reduction of melanin. Thus, our data suggest that pLTA has therapeutic potential for treating hyperpigmentation disorders and can also be used as a cosmetic whitening agent.