• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.3
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• pp.98-105
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• 2011

Patterns and levels of aging vary between the book volume and sheets, even though both are made from the same paper materials. In case of book format, the outside is more easily affected than inner side by environmental factors such as temperature, humidity and air. In this study, the change in optical properties after dry heating accelerated aging was comparatively analyzed to understand the difference of the optical aging characteristics between outside and inner side of the duplicated beeswax-treated volume. It is found that the cover pages of the beeswax-treated volumes were more optically deteriorated than their middle pages. This indicates that outer sides of aging book volume directly exposed to the air is more vulnerable to serious deterioration than inner sides. Also, aromatic compounds such as benzoic acid and cinnamic acid were observed in the investigation of UV/VIS absorbance of the beeswax in each aged sample.

• Genomics & Informatics
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• v.3 no.2
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• pp.66-72
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• 2005

The epidermis is a physiological barrier to protect organisms against environment. During the aging process, skin tissues undergo various changes including morphological and functional changes. The transcriptional regulation of genes is part of cellular reaction of aging process. In order to examine the changes of gene expression during the aging process, we used the primary cell culture system of human keratinocytes. Since UV radiation is the most important environmental skin aggressor, causing skin cancer and other problems including premature skin aging, we examined the changes of gene expression in human keratinocytes after UV irradiation using oligonucleotide microarray containing over 10,000 genes. We also compared the gene expression patterns of the senescent and UV treated cells. Expression of the variety of genes related to transcription factors, cell cycle regulation, immune response was altered in human keratinocytes. Some of down-regulated genes are represented in both senescent and UV treated cells. The results may provide a new view of gene expression following UVB exposure and aging process in human keratinocytes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.2
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• pp.187-196
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• 1991

Aging is the progressive accumulation of changes with time associated with responsible for the ever-increasing susceptibility to disease and death which accompanies advancing age. Lipid peroxides easily produced in the membrane system by the chain reaction of free radicals which occurred from various environmental factors. The amount of lipid peroxides produced in biological system increased with aging process, and lipid peroxidation damages involved in aging process and pathological disorders. Although lipid peroxides have such deleterious effects on the organisms, there are numerous substances and mechanisms which prevent the reaction of peroxide formation and protect the subject from its toxicity. This review provides an overview of how does lipid peroxidation of unsaturated lipids take place by free radical, and what is the intervention of lipid peroxides in pathogenesis of some human diseases, and also how does food restriction influences the aging process and various pathological disorders. The major focus of this paper is to review the evidence indicating that food restriction retards the aging process, and possible mechanisms of its actions. Therefore, it discussed the effects of age and food restriction on life-span, membrane yield, lipid peroxidation, fatty acid composition and peroxidizability, cholesterol and triglyceride levels, prostaglasndin and thromboxane synthesis, which may be concerned with blood flow, membrane fluidity, homeostasis and glomerular filtration rate in living body.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.332-339
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• 2020

This study was a prior study to establish the shelf life of bulletproof helmets, considered the aging factor of bulletproof helmets. To estimate the aging factor of bulletproof helmets, we established a hypothesis that the 'temperature' factor would have the greatest impact on the shelf life of the bulletproof helmet, considering the environmental treatment of the American army's bulletproof helmet's materials. To verify the hypothesis, high temperature acceleration environmental treatment of bulletproof helmets was performed, and the Arrhenius formula was applied to calculate the shelf life. The study result confirmed the negative correlation between bulletproof performance and high temperature, and the influence of temperature as an aging factor was not significant by deriving life by using the Arrhenius model. The limitation of this study is that we couldn't obtain enough samples due to the specificity (miliary supplies) of the test subjects. However, given that the life-related research on bulletproof helmets has not been carried out, this research has great implications and could be used as a reference for improving the Korean Army's bulletproof helmet specifications.

• Environmental Analysis Health and Toxicology
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• v.23 no.2
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• pp.129-138
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• 2008

The purpose of this study was to investigate the effects of frankincense oil in skin aging animal model. Skin aging was induced by both the irradiation of UVB and the application of squalene monohydroperoxide (Sq-OOH) to the back of experimental animals for 4 weeks. And at the same time experimental materials were applied topically. Six to seven weeks female SHR-1 hairless mice were divided into five groups including normal (N: saline), control (C: UVB+Sq-OOH+saline), vehicle control (VC: UVB+Sq-OOH+jojoba oil), positive control (PC: UVB+Sq-OOH+0.01% retinoic acid) and experimental (E: UVB+Sq-OOH+3% Frankincense oil) groups, five animals each group. Lipid lamella and lipid content in stratum corneum of the E group were almost intact with a regular arrangement which were similar to the N group. Collagen fibers in dermis of the E group were almost intact with a regular arrangement which were similar to the N group. Relatively much less number of mast cells and inflammatory cells were found in the E group compared to the C group. The activities of XO, SOD and CAT were no significant difference between the E and N groups. In conclusion, the application of frankincense oil to the skin aging animal model reduced both the generation of free radicals and the damage of skin tissues. Therefore, frankincense oil can be used practically for the prevention or improvement of skin aging in terms of health promotion and beauty for the people.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.4
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• pp.503-509
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• 2021

Objectives: The utility of the system was analyzed by applying the smart safety technology system to the aging pipe rehabilitation facility construction classified as a confined space. Methods: Smart safety management system was applied to a site where the aging pipe rehabilitation work was in progress. The working environment was measured for 25 days, and the toxic gas saturation was analyzed according to the working time and working place. Results: Based on the measured results, two characteristic environmental changes in the confined space were confirmed. First, when working inside an aging pipe, the tendency of carbon dioxide saturation increases with working time and the number of workers. Second, oxygen decreases when working in a space away from the entrance. Conclusions: Various applications of smart safety technology have been confirmed based on the measured data, and this is expected to be useful for environmental characteristic analysis and safety management when applied to a confined space composed with various conditions in the future.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.7
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• pp.1416-1425
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• 2002

In this study, the effects of combined environmental factors on mechanical and thermal analysis properties of graphite/epoxy composites were evaluated by the use of an accelerated aging test. Environmental factors such as temperature, moisture. and ultraviolet were considered. A xenon-arc lamp was utilized for ultraviolet light. and exposure times of up to 3000 hours were applied. Several types of specimens - tensile. bending, and shear specimens those are transverse to the fiber direction, and bending specimens those are parallel to the tiber direction - were used to investigate the effects of environmental factors on mechanical properties of the composites. Also, glass transition temperature, storage shear modulus, loss shear modulus, and tan ${\delta}$ were measured as a function of exposure times through a dynamic mechanical analyzer. In addition. a suitable testing method for determining the effect of environmental factors on mechanical properties is suggested by comparing the results from using two different types of strain measuring sensors. Finally, composite surfaces exposed to environmental factors were examined using a scanning electron microscope.

• Journal of Family Resource Management and Policy Review
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• v.14 no.4
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• pp.323-340
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• 2010

Many social and environmental changes have emerged due to the increasing size of the aging generation. This study explored the current status of the information leisure activity of the aging generation (computer use activity, internet service participation, social community participation and blogging, UCC, etc.) and the need for serious games among elderly consumers. It analyzed the current status of serious game and information leisure span as determined by experts on elderly care at the aging welfare institute. The research methods involved applying content analysis and focus group interviews. The results were as follows: The elderly are willing to enjoy the internet and economics networks. In particular, economic investment, economic news, health, meetings, and communication are the main internet search categories. The results for serious games are less interesting than those for IT participation. The components of usefulness in terms of serious games, as identified by care experts, are simplicity, a user-friendly interface, efficacy, and certainty in using the game device. Care experts recognize that serious games represent a supplementary device to traditional physical and emotional therapy.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.5A
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• pp.417-424
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• 2010

The dynamic properties of laminated rubber bearings used as isolators in structures could be significantly deteriorated because of the change of microstructure in rubber caused by thermal aging. As a result, a catastrophic failure of bridges and buildings unexpectedly occurs when they are subjected to earthquake attack. Here, the dynamic properties of laminated rubber bearings before and after different of compression-shear loading and repeated cycles loadings, ultimated failure test with thermal aging were first measured and compared to each other. The experimental results, the effects of thermal aging on the shear stiffness, energy absorption, and equivalent damping coefficient of laminated rubber bearings are investigated. It is found that the deterioration of dynamic properties of laminated rubber bearings caused by thermal aging is significant and should be taken into account in designing rubber bearings.

• Journal of Industrial Convergence
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• v.20 no.8
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• pp.25-31
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• 2022

This study examines the impact of residential environmental satisfaction on AIP(Aging in Place), and analyzes how their relationship differs depending on housing characteristic variables (ownership type, housing type, and residential area). For this purpose, as of November to December 2020, a questionnaire analysis was conducted on 373 adult males and females residing in Busan and Gyeongnam. The results of this study are summarized in two ways as follows. First, the higher the satisfaction with the residential environment, the higher the AIP. Second, it was analyzed that the positive relationship between satisfaction with the residential environment and AIP was higher in ownership than in rental cases, and further decreased in detached houses compared to apartment houses. In addition, compared to other regions, metropolitan cities or small and medium-sized cities had a higher positive (+) relationship between satisfaction with the residential environment and AIP. This study will provide important implications for policymaking related to population and urban planning.