• Elastomers and Composites
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• v.29 no.5
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• pp.431-435
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• 1994

For recycling of the waste tires, polyurethane binder mixed with the scrapped rubber powders which obtained from tread part of waste tire. This study covered the effect of the binder contents on the mechanical properties of the blend. We also studied the change of the properties after aging on properties compared with those of before aging. The curing reaction of the binder was also investigated in this study. We obtained conclusions the suitable binder content was 15phr in this system.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.4
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• pp.628-638
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• 2010

This study examined the current status of caution labels on cooking utensils made from plastics or glass, toward suggesting improvements in labeling for consumer's safe use. Distributors were categorized into four types, plastic kitchen utensils were categorized into seven types according to usage, and glass kitchen utensils were categorized into two types. Generally, the percentage of cooking utensils made from plastics or glass that have caution labels were not high. For the types of labels on cooking utensils made from plastic and glass, stickers were the most frequently used, and of these, a high percentage scored "fair" in label perception. On the basis of these results, regulations are needed to strengthen caution labels for kitchen utensils.

• Journal of Applied Biological Chemistry
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• v.44 no.4
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• pp.194-198
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• 2001

Contaminated sites are often abandoned for an extended period of time, thus organopollutants becoming sequestered. The information on the initial concentrations of the contaminants would be helpful for the economic bioremediation of the chemicals. The present study estimated the initial concentrations of atrazine and phenanthrene through multiple regression analyses using soil properties and the amount of chemicals available in situ. Percentage mineralized or extracted was best correlated with organic C or logarithm of organic C, and the $R^2$ values were 0.548 and 0.894 for atrazine and phenanthrene, respectively. Estimation of the initial concentration of the chemicals was then calculated from both the percentage mineralized or extracted and the amount of chemicals extracted or mineralized. Results showed that the estimation of the initial concentration of the chemical at the time of contamination is feasible.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.242-249
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• 1997

Stability of bioluminescence was investigated with Photobacterium phosphoreum immobilized on the strontium alginate in order to develope continuous real time monitoring of pollutants. The stability of bioluminescence emission was improved by prolonged aging time. The aging time of ${\geq}40$ min and the cell concentration of ${\leq}0.6\;of\;OD_660$ were selected for the immobilization of P. phosphoreum to give linearity between cell concentrations and bioluminescence intensity. In sensitivity tests using phenol, it was found that this compound quenched bioluminescence proportional to the concentration without lowering of cell growth. The lower value for maximum quenching ($q_s$) and higher dissociation constant ($K_s$) were observed with strontium-alginate immobilized cells compared to free cells. The response of bioluminescence to toxicants was evaluated with the immobilized luminescent bacteria. The sensitivity of the immobilized cells was found to be good in response to toxicants, 4-nitrophenol, salicylate and cadmium, when evaluated with a specific rate of bioluminescence quenching.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.715-720
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• 2003

The chief factors for the penetration and diffusion of chloride ions in concrete are water-cement ratio(W/C), aging, curing conditions, chloride ions concentration of given environment., wet and dry conditions and etc. In this study, of these factors effect of curing conditions such as standard and outdoor curing on the characteristics of chloride ions diffusion in concrete were researched when environmental factors for the penetration and diffusion of chloride ions were constant. For this purpose, the voltages passing through the diffusion cell were measured by using accelerated test method using potential difference, and then diffusion coefficients of chloride ions by using Andrade's method were estimated for 44%, 49.5% and 60% of w/c, respectively. As a result., according to curing conditions correlation among diffusion coefficients of chloride ions, W/C and aging were concluded through multiple regression model.

• Journal of Korean Physical Therapy Science
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• v.2 no.4
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• pp.793-805
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• 1995

The purposes of this review are to know the characteristics and physical changes of elderly person, and to give the information about elderly person when the geriatric physical therapy will be needed in Korea. Current literature on physiological changes that occur in humans owing to aging is reviewed. The musculoskeletal, cardiopulmonary, neurological, perceptual, gastrointestinal, endocrine and immunological systems are discussed. Also, The cognition, personality, and role changes are discussed. We are discussed the changes of aging; biological theory, psychosocial theory and environmental theory. The effects of disuse and of exercise are reviewed. Implications for geriatric physical therapy are suggested.

• Korean journal of aerospace and environmental medicine
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• v.30 no.1
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• pp.30-33
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• 2020

The Republic of Korea is rapidly entering an aging society. With the aging of society, the overseas travel of the elderly is increasing rapidly. According to the Korea Tourism Organization, the number of overseas tourists aged 61 or older last year exceeded 2.5 million, of which over 80 were over 200,000. Age is no longer a limiting factor for traveling abroad, but traveling to unfamiliar places is certainly a challenge. Old people may experience a variety of problems, so special care should be taken. In particular, the aircraft cabin environment is different from the ground, so elderly travelers with respiratory or heart disease require special attention. In this paper, we want to know the precautions and how to prepare for the safe air travel for the elderly.

• Toxicological Research
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• v.24 no.4
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• pp.245-251
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• 2008

Dietary restriction (DR) is the most efficacious intervention for retarding the deleterious effects of aging. DR increases longevity, decreases the occurrence and severity of age-related diseases, and retards the physiological decline associated with aging. The beneficial effects of DR have been mostly studied in non-neuronal tissues. However, several studies have showed that DR attenuate neuronal loss after several different insults including exposure to kainate, ischemia, and MPTP. Moreover, administration of the non-metabolizable glucose analog 2-deoxy-D-glucose (2DG) could mimic the neuroprotective effect of DR in rodent, presumably by limiting glucose availability at the cellular level. Based on the studies of chemically induced DR, it has been proposed that the mechanism whereby DR and 2DG protect neurons is largely mediated by stress response proteins such as HSP70 and GRP78 which are increased in neurons of rats and mice fed a DR regimen. In addition, DR, as mild metabolic stress, could lead to the increased activity in neuronal circuits and thus induce expression of neurotrophic factors. Interestingly, such increased neuronal activities also enhance neurogenesis in the brains of adult rodents. In this review, we focus on what is known regarding molecular mechanisms of the protective role of DR in neurodegenerative diseases and aging process. Also, we propose that DR is a mild cellular stress that stimulates production of neurotrophic factors, which are major regulators of neuronal survival, as well as neurogenesis in adult brain.

• Korean Institute of Interior Design Journal
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• v.22 no.5
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• pp.258-266
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• 2013

Rapidly aging society extends the span of aged life of the elderly people longer than before and this trend raises the issue of holistic health of the aged including their physical, psychological and social health making it necessary to study for environmental development to support this trend. This study intends to explore the direction of residential planning to support the deterioration phenomenon of social networks due to aging. Social networks here are treated as basic conditions for social health. This study researched the diverse types of elderly housings in preparation for the aged society and their spatial characteristics, social affordance characteristics and their potentials for social interactions from the viewpoint of their social relations. literature studies with contents analysis method was used. The results of this study were arranged primarily according to the characteristics of social relations by types of housings. Socially integrated types of housings can be found as inclusive housing type as they have both social characteristics that can be found in houses in general and the elderly housings, they should be considered as desirable types in Korea where collective houses are most popular. Form the existing housing plans housing plan direction should move toward socially integrated housing plans that can protect the elderly people collectively and the direction of housing plans here means the direction from more macro-perspective viewpoint. Therefore, the results of this study are meaningful in adding interpretation from the viewpoint of social relations respective housings and promoting housings for the elderly people more desirably.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.31 no.6C
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• pp.221-229
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• 2011

A core zone of a fill dam is an important part of a dam for cutoff of water. Therefore, the material properties and behavior characteristics of a core zone are very important factors in an analysis of dam stability. However, the investigation on material properties of actual dam core is extremely rare so far. The material properties have been acquired or estimated by indirect methods like a surface wave surveying or empirical equation. In this research, in-situ and laboratory tests were conducted during dismantling an existing dam directly to investigate characteristics of the core zone in terms of the depth and transient variation of properties after construction of the dam. Dynamic material properties like shear wave velocity and shear modulus were measured and compared to other existing empirical correlations. In addition, aging characteristics of dynamic material properties were investigated by a series of laboratory tests.