• Journal of radiological science and technology
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• v.39 no.2
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• pp.263-271
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• 2016

The market size of the bone absorptiometric X-ray system and the number of its approval by Ministry of Food and Drug Safety (MFDS) has annually increased, with a trend of increasing aging population and osteoporosis patients. For approval of manufactured or imported medical devices in Republic of Korea, it is required to submit its technical document. Therefore, it is need to develop the technical document guideline for the bone absorptiometric X-ray system for manufacturers, importers and reviewers. First of all, the technical documents which were already approved were examined and analyzed through MFDS approval administration system. Second, safety and performance test standards and methods that match international standards were drawn after conducting survey of the market status and the technology development trend for it, with examination and analysis of applicable domestic and overseas standards. Third, by operating industry-research-government cooperation, the guideline draft on writing technical document for the bone absorptiometric X-ray system was discussed, collecting their opinion. As a result, it is suitable to international and domestic condition, includes test evaluation methods and offer various information with appropriate examples to civil petitioner, when they write the technical documents.

• International Journal of Highway Engineering
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• v.3 no.3 s.9
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• pp.119-133
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• 2001

The stiffness of chemcrete modified asphalt mixtures increase rapidly with time in the presence f oxygen and high temperature, Sometimes the asphalt pavements that have chemcrete modified asphalt mixture applied on the surface none show premature cracking because of the excessive increase in the stiffness f the asphalt mixtures. To mitigate this premature cracking, the chemcrete modified mixtures have been used as a base course material. In this study, the performance of the chemcrete modified asphalt binder and mixtures are investigated through a course of various laboratory tests including dynamic shear rheometer and bending beam rheometer tests for binders and uniaxial tensile fatigue, wheel tracking, and moisture damage tests for the mixtures. And also the resilient modulus of the conventional and chemcrete modified mixtures are compared based on the test results conducted on the specimens obtained from various in-situ test sections. It can be concluded from the tests results that the chemcrete modified mixtures show better rutting resistance than conventional mixtures. The chemcrete modified mixtures may have low temperature cracking when it is applied in the cold region. The stiffness of chemcrete modified mixtures is approximately 50 percent higher than that of conventional mixtures more than two years after the chemcrete modified mixture was applied in the base course.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.37 no.1
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• pp.61-66
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• 2011

Antioxidant activity of Geranium nepalense subsp. thunbergii extract was evaluated by DPPH free radical scavenging assay. Geranium nepalense subsp. Thunbergii extract contains tannin, (-)epicatechin, kaempferitin, kaepferol -7-rhamnoside, brevifolin, corilagin, pyrogallol, ellagitannin, geraniin, gallic acid, succinic acid, quercetin, protocatechuic acid, etc. Geranium nepalense subsp. Thunbergii showed excellent antioxidant activity compared to positive control, quercetin. Geranium nepalense subsp. thunbergii extract showed a 98.33 % inhibition of DPPH radical at a concentration of $50\;{\mu}g/mL$. Quercetin showed a 78.05 % inhibition of DPPH radical at the same concentration. To investigate reactive oxygen species (ROS) scavenging activity, Geranium nepalense subsp. thunbergii extract was treated to human keratinocytes (HaCaT). $IC_{50}$ value of Geranium nepalense subsp. thunbergii extract was $43.22\;{\mu}g/mL$ and $IC_{50}$ value of quercetin was $102.35\;{\mu}g/mL$. Geranium nepalense subsp. thunbergii extract showed excellent antioxidant activity. Skin irritation test and cytotoxicity test suggested that Geranium nepalense subsp. thunbergii extract is a safe antioxidant ingredient for cosmetics.

• The Journal of Korean society of community based occupational therapy
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• v.6 no.2
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• pp.1-10
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• 2016

Objective : The purpose of this study was to examine the effect of multi-sensory stimulation training on cognitive function and balance skill of the community resident elderly. Methods : 10 participants who is over aged 65 years carry out multisensory stimulation training program for 12weeks, once a week for 60minutes. The multisensory stimulation training program is consisted of total 12 topic based on body schema, gross muscle and tactile stimulation. The result was measured using Mini-Mental State Examination-Korean and Berg Balance Scale to evaluate before and after of cognitive function and balance skill. And after intervention, the satisfaction of the program was investigated. Wilcoxon matched-pair signed rank test was used to compare pre- post difference of cognitive function and balance skill. Results : There was significant difference in cognitive function and balance skill(p<.05) and the satisfaction is positive at the end of the program. Conclusion : The multisensory stimulation training program has positive effects on cognitive function and balance skill for elderly. And the satisfaction is positive at the end of the program. The multisensory stimulation training program can enhance the satisfaction to elderly in the aging society. So, additional studies is needed for efficient use.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.10
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• pp.354-362
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• 2017

Due to population aging and westernized lifestyle, ischemic heart diseases are increasing, and Korea has one of the highest lengths of stay for ischemic heart diseases. Since the increase in the length of stay is a major cause of the increase in medical expenses, it is necessary to prepare a plan to manage the length of stay. Accordingly, this study was conducted to identify the factors influencing the length of stay of ischemic heart disease, and provide the elementary resources necessary for the management of the length of stay. The study subjects were 566 ischemic heart disease patients of a tertiary hospital. As the result of the study, first, the number of inpatients with chest pain as the chief complaint was the largest. Second, the average length of stay was 4.89 days, and the length of stay varied depending on the type of ischemic heart disease. Third, the age of over 75 years, diabetes, and dyspnea were the factors increasing the length of stay. Therefore, for management of adequate length of stay for ischemic heart disease, it is important to prevent the progression of illness through blood sugar control for ischemic heart disease patients with diabetes. Also, it is necessary to prepare a system where patients can visit hospitals as fast as possible if they have any symptoms.

• Journal of Digital Convergence
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• v.14 no.4
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• pp.11-17
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• 2016

This study is to examine the effect that the degree of alcohol use and the factor of family relationship have on alcohol related problem with elderly people over 65 years old. The study utilized the data from Korea Welfare Panel Study in 2014 published in 2015, which is annually conducted nationwide study. AUDIT (Alcohol Use Disorder Identification Test) of the World Health Organization scale to assess the drinking problem in the study was used. The collected data were analyzed using SPSS 21.0. Presenting some discussions on the basis of the results of this study is as follows. First, looking at a cross-analysis of gender differences in drinking problems, elderly men and elderly women showed different degrees of alcohol problems. Second, looking at demographic characteristics that influence whether a drinking problem, younger age showed a serious drinking problem. Third, looking at the effect that depression and family relationship have on alcohol problem, depression appeared to have relatively more serious effect than the family relationship. According to the above finding, physical and mental health for healthy aging are important factors of the quality of life so a preventive approach to maintain healthy habits is considered to be essential.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.1-7
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• 2008

The antioxidative, antimutagenic and cytotoxic activities of ethanol extract from Cornus officianalis have been studied. The antioxidant activity of the ethanol extract was measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH) method. The inhibition effects on the mutagenicity in Salmonella Typhimurium TA100 were evaluated by Ames test and cancer cell inhibitory effects in Hep3B cell and HeLa cell were tested by MTT assay. Cornus officianalis had an important free radical-scavenging activity towards the DPPH radical. At a concentration of 500 ppm, the DPPH radical-scavenging activity of Cornus officianalis was similar to that of L-ascorbic acid. None of the extracts produced a mutagenic effect on S. Typhimurium TA100. The ethanol extract from Cornus officianalis showed about 77% of inhibition at 500 ppm on the mutagenicity induced by 4-nitroquinoline-1-oxide. The extract from Cornus officianalis showed strong cytotoxicity against Hep3B and HeLa cells, with inhibition of 83 and 78% at a dose of $700{\mu}g$/plate, respectively. Moreover, the ethanol extracts had 34.33 mg H.E/g of polyphenols and 5.67 mg Q.E/g of flavonoids, respectively. Therefore, the present study showed antioxidative, antimutagenic and anticancer potential of the ethanol extract from Cornus officianalis.

• Journal of the Korea Concrete Institute
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• v.24 no.2
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• pp.195-204
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• 2012

In the construction of high-rise buildings, bent re-bars are manually straightened to connect slabs to core-walls, which are usually cast before floor structures. During cold bending and straightening of re-bars, plastic deformation causing work hardening, Bauschinger effect and aging hardening is unavoidable. Tensile tests of coldly bent and straightened re-bars were conducted with test parameters of grade, diameter, and bend radius of re-bars as well as age between bending and straightening. Test results showed that proportional limits were lower and strain hardening occurred without yield plateaus. Inside and outside of re-bars with compression and tension deformations, respectively, during bending showed lower yield points due to Bauschinger effect and no yield plateaus due to work hardening, respectively. When re-bar grade was higher, yield point became significantly lower where Grade 400 re-bars had yield strengths lower than specified yield strength of 400 MPa. Because the surface of re-bar has higher strength than the core of re-bar, Bauschinger effect was more obvious for higher-grade re-bars. When age between bending and straightening was greater, yield strength increased and elongation decreased (i.e. embrittlement occurs). Using measured data, stress-strain relationship for straightened re-bars was developed based on Ramberg-Osgood model, which can be used to evaluate stiffness of joints when straightened re-bars are applied.

• Journal of Dental Rehabilitation and Applied Science
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• v.32 no.3
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• pp.184-193
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• 2016

Purpose: To evaluate marginal leakage of bulk fill flowable composite resin filling with different curing time by using microcomputed tomography technology. Materials and Methods: 30 previously extracted human molars were randomly divided into 6 groups based upon restorative system and different curing time. Class II cavities (vertical slot cavities) were prepared. An individual metallic matrix was used to build up the proximal wall. The SonicFill or SureFil SDR flow was inserted into the preparation by using 1 bulk increment, followed by light polymerization for different curing times. The different exposure times were 20, 40, and 60 seconds. All specimens were submitted to 5,000 thermal cycles for artificial aging. Micro-CT scanning was performed by using SkyScan 1272. One evaluator assessed microleakage of silver nitrated solution at the resin-dentin interface. The 3D image of each leakage around the restoration was reconstructed with CT-Analyser V.1.14.4. The leakage was analyzed with the Mann-Whitney test. Results: Significant differences were observed between the light curing times, but no significant differences were found between the bulk fill composite resins. Increasing in the photoactivation time resulted in greater microleakage in all the experimental groups. Those subjected to 60 seconds of light curing showed higher microleakage means than those exposed for 20 seconds and 40 seconds. Conclusion: Increasing the photoactivation time is factor that may increase marginal microlekage of the bulk fill composite resins. Further, micro-CT can nondestructively detect leakage around the resin composite restoration in three dimensions.

• Korean Journal of Agricultural Science
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• v.14 no.1
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• pp.156-163
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• 1987

In these experiment, the conditions of entrapping immobilization of Zygosaccharomyces rouxii that participate in the soysauce brewing are investigated. And carried out the fermentation and aging test by immobilized Zygosaccharomyces rouxii with the hydrolyzed solution prepared from soysauce koji. The results obtained were as follows: 1. Immobilizing conditions of Zygosaccharomyces rouxii. 1) When the concentration of Na-alginate solution is 2.0-2.5%, the bead formation was very good. And the concentration of Na-alginate solution not influenced on the fermentation activity of immobilized Zygosaccharomyces rouxii. 2) Effect of ratio of the precultured Zygosaccharomyces rouxii solution and Na-alginate solution on the fermentation activity of immobilized Zygosaccharomyces rouxii was not highly recognized. But if the ratio of precultured Zygosaccharomyces rouxii solution increased, the fermentation activity of immobilized Zygosaccharomyces rouxii was slightly high. 3) The fermentation activity of immobilized Zygosaccharomyces rouxii that grew over 36hrs was higher than that grew below 24hrs. 4) Increasing the ratio of immobilized Zygosaccharomyces rouxii gel to the fermentative medium, the fermentation activity of Zygosaccharomyces rouxii was higher. 2. The fermentation test by immobilized Zygosaccharomyces rouxii with the hydrolyzed solution of soysauce koji. 1) When fermented for about 96 hrs, the alcoholic fermentation almost stopped and alcohol concentration into the hydrolyzed solution of soysauce koji was 2.6%(v/v) approximately.