• 한국의류학회지
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• 제29권3_4호
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• pp.561-568
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• 2005

The irradiation of Ultra-Violet (UV) is an efficient treatment for polymer to improve hydrophilic properties. 4-Channel PET knit fabrics were treated with UVA and UVC to develop functional and environment-friendly fabric. The fabric was treated with various treatment times and distances from UV lamps having different wavelength. FT-IR and XPS investigated the chemical changes. To confirm the change of surface properties, contact angle, surface energy and SEM were examined. The study of UV as a treatment for PET knit fabric shows significant changes in chemical and surface properties, which is proved by analyses. FT-IR and XPS analyses prove the augmentation of carboxylic, Hydrophilic groups on the surfaces treated by UV. The increase of water contact angle and surface energy means more water wettable and surface energy of PET film was substantially increased by UV irradiation time. The ageing after surface treatment had little influence on the surface energy of the irradiated PET film. SEM proves the surface modification of PET such as etching, bubble and crack. The negative effects are increased in accordance with increasing treatment time.

• 열처리공학회지
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• 제20권5호
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• pp.243-249
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• 2007

The age hardening behavior and mechanical properties of an extruded Al-Zn-Mg-(Cu)-0.1 wt.%Sc alloy were investigated with the Sc addition and ageing temperature. The results showed that the $Al_3Sc$ compounds were formed by Sc addition and distributed preferentially along the extrusion direction. The age hardening of Al-Zn-Mg-Cu-0.1 wt.%Sc alloy which was treated by T6 process was more significant than that of Al-Zn-Mg-0.1 wt.%Sc alloy. The tensile property of Al-Zn-Mg-Cu+0.1 wt.%Sc alloy was also higher than that of Al-Zn-Mg-0.1 wt.%Sc alloy, which is 691 MPa and 584 MPa in strength and 9% and 11% in elongation, respectively.

• 한국안전학회지
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• 제11권1호
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• pp.67-74
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• 1996

In order to investigate the effect and reliability coming up to properties of the matter due to the change of solid structure in dielectrics, the effect of dielectric characteristics for thermal treated LDPE film was made researches. Specimens of LDPE with thickness 100 [$\mu\textrm{m}$] were investigated into the change of solid structure by ageing. Thermal treated specimen were made, that were after applying heat at 100 [$^{\circ}C$] for 1 [hour] \circled1 air-cooled specimen slowly, \circled2 water-cooled specimen under the ,com temperature, \circled3 liquid nitrogen gas-cooled specimen rapidly. With specimen of thermal treated three types turn out and original, it was for dielectric characteristics to be experimented in the temperature range of 20~120 [$^{\circ}C$], frequency range of 30~1.5${\times}10^5/$[Hz], appling voltage from 300 to 1500[㎷]. Consequently, the degree of crystallinity was changed with 49~57 [%] according to the thermal treatment. In case of frequency, 100 [Hz], on the thermal dependance in dielectric characteristics, tan decreases due to cooling method.

• Journal of Animal Science and Technology
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• 제46권3호
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• pp.405-414
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• 2004

본 연구는 한국 재래돼지의 도축전 절식과 숙성이 longissimus dorsi(LD), biceps femoris(BF) and triceps brachii(TB)의 육질에 미치는 영향을 조사하였다. 18 시간동안 절식은 LD에서 유의적으로(P < 0.05) 높은 최종 pH을 보였고, BF도 유사한 경향을 나타냈다. 근육 온도는 절식유무에 영향을 받지않아, 이 결과는 각 처리구의 돼지들은 각기 다른 온도와 pH의 영향을 받았다는 것을 의미한다. 이러한 영향은 LD의 경우 절식을 하지 않은 돼지에서 유의적으로 높은(P < 0.05) hunter $L^*$ 값과 가열감량에서 나타났다. 하지만 전단력은 차이가 없었다. 또한 BF와 TB의 육질은 도축전 절식유무에 의해 영향을 받지 않았다. LD에서 전단력은 숙성 7일까지 감소하였고, BF와 TB는 14일까지 유의적으로(P < 0.05) 감소했다. 숙성기간중 LD와 BF, 그리고 LD와 TB의 상관관계를 보았을 때, LD의 전단력 6kg은 BF와 TB에서 각각 6과 3.5 kg을 보였다. 본 연구의 결과에 따르면, 도축전 급여는 시각적인 육색은 개선하나, 가열감량을 증가시켜 맛은 감소시킬 것으로 판단되었다. 한편 LD의 숙성은 7일이 적절한 것으로 나타났고, TB와 같이 근본적으로 연한 고기는 숙성은 가열감량을 증가시키므로 숙성하지 않는 것이 바람직하다고 판단되었다. BF와 TB에서는 14일 숙성은 연도는 증가하나 다즙성은 감소할 것으로 판단되었다.

• 소성∙가공
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• 제15권8호
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• pp.621-627
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• 2006

Recently, micro-alloyed steels which could eliminate heat treatments after forging has been developed. These non heat-treated micro-alloyed steels have several advantages over the conventional quenched and tempered steel for cold forging. First of all, long components can be fabricated with a better dimensional accuracy since bending of long forged part after quenching treatment could be avoided. And it is possible to eliminate two energy consuming heat treatment steps, which are a spherodizing before forging and quenching/tempering after forging. Therefore, more cost effective and environment friendly process could be designed. However, there is non-uniform distribution of strain occurred across the forged part, since these non heat-treated micro-alloyed steel use strain hardening mechanism. In the present study, it was investigated how to lessen non-uniformity and increase strength together for cold forging when a baking heat treatment is applied in micro-alloyed steels. For this purpose, micro-alloyed steels developed by Se-A Besteel recently was used for the experiment.

• 대한치과의사협회지
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• 제50권1호
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• pp.6-12
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• 2012

As in all other parts in the body, oral tissue also undergoes dramatic changes with increasing age. Since these changes occasionally go beyond physiological scope, which may result in pathological changes, it is essential for dentist to understand changes caused by normal aging process. With increasing age, tooth morphology and occlusion also varies, especially loss of hard tissue, which is taking place in lifelong time, occurs as a result of tooth wear. When this loss of hard tissue is presented rapidly or excessively, functional and esthetical problems are raised, resulting in lowering quality of life of patient as well as making dental treatment for oral rehabilitation even more complex. Therefore, based on understanding of change in occlusion with increasing age, strategic approaches for maintenance of oral health in both functional and esthetic aspect are required as appropriate restoration and maintenance for progressive tooth wear enables desirable occlusal relationship. Carefully planned-restorative treatment in accordance with changed occlusal relationship is also required in the same context. Instead of taking changes in oral tissue as only a consequence of ageing, it is vital to educate patient and his or her guardian, assuring maintenance of oral hygiene and regular dental check-up are of utmost importance for improved oral health.

• 한국정보전자통신기술학회논문지
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• 제9권4호
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• pp.404-413
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• 2016

본 연구는 주관적 건강상태가 의료시설 이용에 영향을 미친다는 전제로 주관적 건강상태를 파악하고, 또한 주관적 건강상태에 따른 의료시설 이용의 차이를 만성질환자별로 분석하여 의료시설 이용 시 표준지침의 기초자료로 제공되는 것을 목적으로 하였다. 대표성 있는 고령화패널 자료를 사용하여 총 7,486명을 분석하였다. 만성질환자는 주관적 건강상태에 따라 의료시설 이용에 차이를 나타내고 있었으며, 특히 한의원 한방병원과 치과 치료에 있어서 질환별 차이가 두드러졌다. 하지만 이차자료의 활용으로 의료이용에 영향을 미치는 여러 변수들을 통제하지 못하여 후속 연구들을 제시하는데 본 연구의 의의를 두었다.

• 혜화의학회지
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• 제8권1호
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• pp.689-710
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• 1999

Bobitang(BBT) is one of the most important prescription that has been used in oriental medicine(dongyibogam) for recovering spleen condition. The study was done to evaluate effects of BBT water extract on the spleen lipid peroxide content and metabolic enzyme system changes. After pretreatment of BBT I (100mg/kg), BBT II(250mg/kg), BBT III(350mg/kg), BBT IV(500mg/kg) for 1 week, lipid peroxide content and metabolic enzyme system changes of the spleen was measured in 8 months rats. The results were obtained as follows : 1. The content of spleen lipid peroxide was significantly decreased in all experimental groups as compared with control, and best in BBT III IV treated groups. 2. The activity of spleen superoxide generation was significantly decreased in all experimental groups as compared with control, and best in BBT IV III treated groups. 3. The activity of cytochrome P-450 and aminopyrine demethylase wasn't significant change. 4. The activity of aniline hydroxylase was significantly decreased in BBT IV II treated groups, xanthine oxidase was significantly decreased in all experimental groups, aldehyde oxidase was significantly decreased in BBT IV treated group as compared with control. 5. The activity of antioxidant enzymes as superoxide dismutase, catalase, glutathione peroxidase was significantly increased in all experimental groups as compared with control. 6. The activity of glutathion S-transferase was significantly increased in all experimental groups, the concentration of spleen glutathione was significantly increased in BBT IV treated group as compared with control. 7. The activity of ${\gamma}$ -glutamylcystein synthetase was significantly increased in BBT III IV I treated groups as compared with control, the activity of glutathione reductase wasn't significant change. From the above results, BBT is cosidered to have effect of remove peroxide content and free radical that was made during ageing process. It is expected that treatment of BBT can be applied in future clinical study of delaying the ageing process.

• 한국노년학
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• 제36권4호
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• pp.1059-1074
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• 2016

본 연구는 노인의 평생학습활동과 삶의 만족도, 우울의 구조적 관계를 분석하는데 목적이 있다. 본 연구 목적 달성을 위한 분석자료로 제4차(2012) 고령화연구패널(Korean Longitudinal Study of Ageing : KLoSA) 기본 조사 자료를 사용하여, 항 우울제를 복용하지 않는 만65세 이상 노인 4,096명을 대상으로 분석하였으며 분석결과는 다음과 같다. 첫째, 노인의 비형식교육 활동 및 무형식학습 활동은 삶의 만족도에 정의 영향을 미치는 것으로 나타났다. 둘째, 노인의 비형식교육 활동 및 무형식학습 활동은 우울에 부의 영향을 미치는 것으로 나타났다. 셋째, 노인의 우울은 삶의 만족도에 부의 영향을 미치는 것으로 나타났다. 넷째, 노인의 비형식교육 활동 및 무형식학습 활동은 우울을 감소시켜 삶의 만족도에 정의 영향을 미치는 것으로 나타나 우울이 부분 매개효과가 있는 것으로 확인되었으며, 비형식교육보다 무형식학습 활동의 간접효과가 더 큰 것으로 확인되었다. 이러한 연구결과를 바탕으로 실천적 함의를 제안하였다.

• Reproductive and Developmental Biology
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• 제37권4호
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• pp.281-287
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• 2013

In mammal, unfertilized oocytes remain in the oviduct or under in vitro culture, which is called "oocyte aging". This asynchrony negatively affects fertilization in pre- and post-implantation embryo development. Caffeine a phosphodiesterase inhibitor is known to rescue oocyte aging in several species. The objective of this study is to determine the cytoskeleton distribution in aged oocytes and the embryo developmental ability of aged oocytes in the present or absence of caffeine during maturation. Caffeine treatment increased the incidence of normal spindle assembly of aged oocytes (treatment, $67.57{\pm}4.11%$ aging, $44.61{\pm}6.4%$) and no significant differences compared to control group. Fluorescence values were compared using ROS (Reactive oxidation species) stain. Fluorescence values appear of control group intensity rate ($51.53.{\pm}3.80$), aging group ($68.10{\pm}5.54$) and treatment of caffeine ($45.04{\pm}2.98$). Aged oocytes that were derived from addition of caffeine to the IVM (in vitro maturation) medium had significantly increased 2-cell that developed to the blastocyst stage compared to the aging group. Blastocysts, derived from caffeine treatment group, significantly increased the total cell number compare aging ($90.44{\pm}10.18$ VS $67.88{\pm}7.72$). Apoptotic fragments of genomic DNA were measured in individual embryo using TUNEL assay. Blastocyst derived from caffeine treatment group decreased significantly the apoptotic index compared to blastocyst derived from aging group. In conclusion, we inferred that the caffeine treatment during oocyte aging can improve the developmental rate and quality in bovine embryos developing in vitro.