• Journal of the Korean Applied Science and Technology
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• v.40 no.4
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• pp.856-867
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• 2023

Due to the increase in fine dust caused by environmental pollution, oxidative damage and aging of the skin are accelerated. In this study, the antioxidant, hyaluronic acid, filaggrin, MMP-1, and ROS level of selected herbal extracts were evaluated to confirm the protective efficacy of keratinocytes treated PM10. As a result, the antioxidant capacity of 1,1-diphenyl-2-picrylhydrazyl(DPPH), 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid(ABTS), and FRAP assay increased in a concentration-dependent manner. Keratinocytes the group treated with 300 ㎍/ml of PM10, hyaluronic acid and filaggrin decreased by more than 50%, and increased in the group treated with extracts of Alpinia officinarum, Ulmus macrocarpa, and Ulmus macrocarpa but decreased when the extract was treated, which is evaluated as inhibiting the degradation of collagen and elastin. In addition, in the case of ROS measurement using zebrafish embryos, it was confirmed that the extract was reduced when the extract was treated 25 ㎍/ml, the intensity of fluorescence similar to the negative control was shown, confirming that the production of ROS was significantly reduced. Through this study, the selected oriental medicinal materials, Alpinia officinarum, Ulmus macrocarpa, and Ulmus macrocarpa, protect the skin from fine dust. It is thought that it can be used as an anti-aging product for skin improvement as a material that can be improved or improved.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2004.09a
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• pp.233-241
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• 2004

A new alloy definition will be presented concerning increasing demands for the board level reliability of miniaturized interconnections. The damage mechanism for LFBGA components on different board finishes is not quite understood. Further demands from mobile phones are the drop test, characterizing interface performance of different package constructions in relation to decreased pad constructions and therefore interfaces. The paper discusses the characterization of interfaces based on SnPb, SnPbXYZ, SnAgCu and SnAgCuInNd ball materials and SnAgCuInNd as solder paste, the stability after accelerated tests and the description of modified interfaces strictly related to the assembly conditions, dissolution behavior of finishes on board side and the influence of intermetallic formation. The type of intermetallic as well as the quantity of intermetallics are observed, primaliry the hardness, E modules describing the ability of strain/stress compensation. First results of board level reliability are presented after TCT-40/+150. Improvement steps from the ball formulation will be discussed in conjunction to the implementation of lead free materials In order to optimize ball materials for area array devices accelareted aging conditions like TCTs were used to analyze the board level reliability of different ball materials for BGA, LFBGA, CSP, Flip Chip. The paper outlines lead-free ball analysis in comparison to conventional solder balls for BGA and chip size packages. The important points of interest are the description of processability related to existing ball attach procedures, requirements of interconnection properties and the knowledge gained the board level reliability. Both are the primary acceptance criteria for implementation. Knowledge about melting characteristic, surface tension depend on temperature and organic vehicles, wetting behavior, electrical conductivity, thermal conductivity, specific heat, mechanical strength, creep and relaxation properties, interactions to preferred finishes (minor impurities), intermetallic growth, content of IMC, brittleness depend on solved elements/IMC, fatigue resistance, damage mechanism, affinity against oxygen, reduction potential, decontamination efforts, endo-/exothermic reactions, diffusion properties related to finishes or bare materials, isothermal fatigue, thermo-cyclic fatigue, corrosion properties, lifetime prediction based on board level results, compatibility with rework/repair solders, rework temperatures of modified solders (Impurities, change in the melting point or range), compatibility to components and laminates.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2004.09a
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• pp.211-219
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• 2004

A new alloy definition will be presented concerning increasing demands for the board level reliability of miniaturized interconnections. The damage mechanism for LFBGA components on different board finishes is not quite understood. Further demands from mobile phones are the drop test, characterizing interface performance of different package constructions in relation to decreased pad constructions and therefore interfaces. The paper discusses the characterization of interfaces based on SnPb, SnPbXYZ, SnAgCu and SnAgCuInNd ball materials and SnAgCuInNd as solder paste, the stability after accelerated tests and the description of modified interfaces stric시y related to the assembly conditions, dissolution behavior of finishes on board side and the influence of intermetallic formation. The type of intermetallic as well as the quantity of intermetallics are observed, primaliry the hardness, E modules describing the ability of strain/stress compensation. First results of board level reliability are presented after TCT-40/+150. Improvement steps from the ball formulation will be discussed in conjunction to the implementation of lead free materials. In order to optimize ball materials for area array devices accelareted aging conditions like TCTs were used to analyze the board level reliability of different ball materials for BGA, LFBGA, CSP, Flip Chip. The paper outlines lead-free ball analysis in comparison to conventional solder balls for BGA and chip size packages. The important points of interest are the description of processability related to existing ball attach procedures, requirements of interconnection properties and the knowledge gained the board level reliability. Both are the primary acceptance criteria for implementation. Knowledge about melting characteristic, surface tension depend on temperature and organic vehicles, wetting behavior, electrical conductivity, thermal conductivity, specific heat, mechanical strength, creep and relaxation properties, interactions to preferred finishes (minor impurities), intermetallic growth, content of IMC, brittleness depend on solved elements/IMC, fatigue resistance, damage mechanism, affinity against oxygen, reduction potential, decontamination efforts, endo-/exothermic reactions, diffusion properties related to finishes or bare materials, isothermal fatigue, thermo-cyclic fatigue, corrosion properties, lifetime prediction based on board level results, compatibility with rework/repair solders, rework temperatures of modified solders (Impurities, change in the melting point or range), compatibility to components and laminates.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.34-42
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• 2002

This research was carried out to investigate water repellent effectiveness of natural oil treated wood. Linseed oil, castor oil, olive oil, bean oil, perilla oil and sunflower oil were used in this test. For evaluation of water repellent of natural oil treated wood, moisture absorption test, water-drop contact angle test and color difference test of accelerated decomposition by UV and water were used. The moisture absorption amount of natural oil treated wood was less than untreated wood until 3 hours, but it was increased with time, there was no big difference with oil treated wood and untreated wood after 48hours. Oil treated wood and untreated wood showed big difference on contact angle test. It was no big difference by kind and oil concentration. Natural oil treated wood did not showed stability on the weather aging test. Contact angle test could be used on evaluation of wood surface status treated with natural oil.

• International Journal of Highway Engineering
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• v.18 no.6
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• pp.41-50
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• 2016

OBJECTIVES : In this study, microstructural components of crumb rubber modified asphalt (CRMA) binder were investigated using environmental scanning electron microscope (ESEM). To clearly understand the elemental composition of the CRMA binder, energy dispersive X-ray spectroscopy (EDX) was employed on the ESEM samples. METHODS : CRMA binders were produced using open blade mixers at $177^{\circ}C$ for 30 min. The binders were artificially aged through a series of accelerated aging processes. Sample preparation was done by making a mold shape on the glass slide. Thereafter, the morphology of the CRMA binder was observed using the ESEM coupled with the EDX. RESULTS : The images captured from the ESEM indicate that the unaged CRMA binder appears to have a single-phase continuous nonuniform structure after the addition of crumb rubber particles, whereas the artificially aged CRMA binder was observed to have two different phases. ESEM coupled with EDX shows detailed internal structure of the modified binders compared to other technologies (i.e., optical microscopy, atomic force microscopy, and conventional scanning electron microscope). CONCLUSIONS : The captured images resemble the internal structures such as the viscous properties of the unaged CRMA binder and the interaction between the rubber particles and the base binder at aged condition. ESEM is a powerful instrument and with the introduction of EDX, it provided more details of the network microstructure of the asphalt binder. ESEM coupled with EDX is recommended for use in future investigation of microstructure of asphalt binders.

• Journal of the Korean Institute of Rural Architecture
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• v.21 no.4
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• pp.17-24
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• 2019

It has been long time since the local small-and-medium cities had lost their vitality due to the progress of aging, economic decline in urban areas, the lack of new growth engines, and the declining population in korea. In addition, since the implementation of the local self-governing system, the creation of new urban areas and the transfer of the administrative institutions to the outskirts of a city have accelerated the decline of old downtown. Rather, local small-and-medium cities would have a problem to make urban regeneration impossible. Under the recognition of such problems, individual self-governing entities have come up with numerous policies and implemented various policies for the revitalization of local small-and-medium cities, but it is a condition that the effect of their efforts falls shorts of expectations, such as the space of the similar style, which has been widespread in developed countries, simple restoration, and a few structural changes. In this regard, the part to be realized anew is to enhance the attractiveness of small-and-medium cities. However, is not possible to raise the overall attractiveness in a short time in reality. To select local assets to be utilized in urban regeneration, it is judged that gathering opinions of local residents is more important than any other thing. Accordingly, this study intends to present positive outcome for the purpose of the revitalization of local small-and-medium cities by finding the factors which can remind us of the collective memory of Jinju city and selection the critical factors to determine a detailed project plan from the perspective of urban regeneration.

• Journal of Agricultural Extension & Community Development
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• v.22 no.2
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• pp.159-173
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• 2015

The purpose of this study was to identify the conditions of neighborhood facilities for the elderly, paying special attention to the accelerated aging phenomenon in rural areas of Korea. We contrived a new index to measure spatial accessibility for people aged over 65 years, and we analyzed spatial accessibility by focusing on community facilities: public bath facilities, beauty shops, rural public facilities, markets, big stores, and large-scale retail shops. The most outstanding spatial accessibility among community facilities was found with the rural public facilities thanks to governmental installing adequate facilities in the past, followed by the beauty shops and the public bath facilities. In contrast, spatial accessibility of the markets was in the lowest. Spatial accessibility of community facilities for the elderly exhibited high variability among the rural areas. We confirmed significant inequality of spatial accessibility in all facilities we studied. The areas that had better spatial accessibility diverse combinations of the facilities. The areas that had worse spatial accessibility were, on the whole, consistent with traditional undeveloped regions. In the near future rational planning of facilities will be needed to supply adequate accessibility in targeted areas which currently had low accessibility. In order to improve the spatial accessibility of neighborhood facilities, the most essential factor is to take into account the geographical distribution patterns of rural settlements.

• Journal of the Korea Institute of Building Construction
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• v.15 no.6
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• pp.607-614
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• 2015

Generally surface finishing of building is done with water paint that performs basic water repellency and resisting. When painting the exterior of the building with water paint, application method is easy and inexpensive and it has the advantage of building maintenance. But surface finishing of water paint is easy to discolored or aging due to ultraviolet light so the effect is not satisfying than expected. Therefore this study is to analyze durability of water-repellent paints mixed with water-repellents as outer surface finishing materials, and evaluate its feasibility. Color change and color different due to the accelerated time were tested, and the feasibility was evaluated based on the test results. The experimental results of color different, brightness different and chromaticity suggested that water-repellent paints mixed with water-repellents were suitable for finishing materials. Considering overall general durability performances, stable mixing ratios were 2, 5, and 8%.

• 대한근관절건강학회:학술대회논문집
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• 1996.04a
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• pp.110-121
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• 1996

It is well defined that osteoporosis is an age related disorder and associated with decreased bone mass. It is one of the most important disease lacing the aging population because of its association with fracture of the hip, vertebrae and distal radius. The disease provoke a significant economic burden and major public health problem of an elderly. The life-time risk of hip fracture in white women is approximately 15% which is equal to the combined risk of breast, uterine, and ovarian cancer. Despite its deleterious effect on women's health, knowledge of the epidemiology of osteoporosis in Korea is only beginning. 1970 in Korea has non as the crossover period between the chronic and an Infectious diseases. As the result, the infant mortality declined and an elderly population in Korea increased significantly in the past decade, The average life expectancy of women in Korea is now about 75 years. Thus, the majority of Korean women will spend approximately one-third of their life in the postmenopause state. Therefore, better understanding of bone metabolism and fracture incidence in Korean population is a great interest for the medical community as well as for public health. Currently, no population based epidemiologic data are available to support the incidence of osteoporotic fractures in Korea. However, available data suggest that significant declining of bone mineral density (BMD [g/$cm^2$]) has been occurring in Korean women after menopause. In same population, peak BMD was observed around 33-39 years of age and continue to decline thereafter. An accelerated bone losses occur after the menopause and the average loss is approximately 13% within 15 years from the menopause. The incidence of fracture was highly correlated with an age and bone mineral density. The mean age of menopause in Korean women was 47 years and this age appears to getting younger when analyzed by the birth cohort. An earlier menopausal age and increase life expectancy place Korean women at increase risk for osteoporosis and bone fracture. Korean or Asian women are no longer protected from the risk of bone fracture. Therefore, an early prevention or intervention schemes are essential before the outbreak of osteoporosis and/or fracture occurs in Korean or Asian women.

• Korean Journal of Food Science and Technology
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• v.17 no.1
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• pp.8-14
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• 1985

In order to give the unique flavour of traditional Doenjang (Korean-style soybean paste) to commercially manufactured soybean paste, the addition of Bacillus licheniformis and Saccharomyces rouxii was tried and their influences were investigated. The addition of B. licheniformis and S. rouxii in soybean paste decreased the content of reducing sugars. By the addition of B. licheniformis, the contents of amino type nitrogen and titrable acidity were increased. The content of ammoniacal nitrogen was reduced and ethyl alcohol production was increased by the addition of S. rouxii. The viable counts of molds showed the decreasing tendency during the aging and it was accelerated by the addition of B. licheniformis and S. rouxii. Acetaldehyde, acetone, ethylacetate, methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol and isopropyl alcohol were detected from the vapor of all tested ripen soybean pastes, while in a traditional Doenjang, isoamyl alcohol and isobutyl alcohol were not. The B. licheniformis and S. rouxii added sample showed richest free amino acid content. In organoleptic test the B. licheniformis and S. rouxii added sample showed the most excellent overall acceptability.