• 한국농공학회논문집
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• 제57권4호
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• pp.11-19
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• 2015

The important properties of EVA (ethylene vinyl acetate) redispersible polymer was waterproof, densification of internal pore space of concrete and ball bearing and micro filler. Also, the significant role of polypropylene(PP) fiber was crack control and blockade of movement for deterioration factors. The most studies for EVA were limited in the field of mortar and PP fiber reinforced concrete had been studied in the state of being restricted unit water content, rich mix and mixing much of the fiber without considering construction site. Therefore, the control mix design were applied in ready mixed concrete using 10 % fly ash of total cement weight used in batch plant. On the basis of control mix design, EVA contents ranging from 0 % to 10 % of total cement weight and PP fiber contents ranging from 0 % to 0.5 % of EVA concrete volume were used in the mix designs. The results showed the maximum compressive strength value was measured at EVA 5.0 % and PP fiber 0.1 %, the minimum water absorption ratio was at EVA 10 % and PP fiber 0 %, the durability factor for freezing and thawing resistance was at EVA 5.0 % and PP fiber 0.3 % and the minimum weight reduction ratio of resistance to sulfuric acid attack was at EVA 10 % and PP fiber 0.5 % after curing age 42days. Meanwhile, From these results, PP fiber reinforced EVA concrete would be very benefit, if each optimal mix types were used in hydraulic structures, underground utilities and agricultural structures.

• 비파괴검사학회지
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• 제19권4호
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• pp.277-287
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• 1999

탄소섬유 복합재료 T 조인트 시험편에 대한 접착특성 및 파손과정을 조사하기 위하여 단순인장 및 하중-제하 인장시험이 수행된다. 시험편은 스킨과 프레임 구조를 가지며, 동시성형과 2차 접착법에 의한 두 종류의 시험편이 제작된다. 단순인장시험동안 시험편의 손상 개시 및 진전시에 AE 특성을 측정하였고, 하중-제하 인장시험동안 진전된 균열길이는 CCD 카메라를 이용하여 측정된다. 또한 시험편 내부의 크랙면 윤곽에 대한 조사는 초음파 C-scan이 사용된다. AE 신호가 급격히 증가하는 하중과 하중-시간 곡선에서 하중강하점은 5% 이내의 오차로 비교적 잘 일치한다. 두 종류의 시험편의 초기균열은 동일한 위치인 중앙 누들부에서 발생되나 최종파단은 동시성형의 경우, 누들부에서, 2차 접착의 경우, 스킨/프레임 끝단에서 일어난다. 이런 결과로부터 두 종류의 시험편은 성형방법에 따라 서로 다른 파손 모드를 보인다.

• 대한예방한의학회지
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• 제18권2호
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• pp.47-58
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• 2014

Objective : In Oriental medicine, the concept of Preventive Treatment Disease(治未病, PTD) is intended to actively deal with changes in modern disease patterns due to increase in chronic diseases. In China, preventive health service program based on PTD Theory are being carried out aimed at improving and/or preventing people's health. Method : For the introduction of PTD program based preventive service in Korea for the promotion of people's health, I would like to consider its possibility by reviewing the PTD program being conducted in China. Results : China's preventive health service programs based on PTD Theory started in 2008 for the purpose of promoting people's health and reducing medical expenses by providing medical services tailored to individuals. Regarding the effects of PTD program based preventive health service, improvement of discomforting symptoms comprised 73.04% of responses. As to service items, health guidance, Traditional Chinese Medicinal diagnosis, and preparation of health records were answered as being important. The importance of food and internal medicines for preventing and/or curing PTD Theory are also recognized. Also, as to satisfaction level, 90.64% responded as being satisfied in the order of the level of service providers, their attitudes, service processes, items, costs, and environments. Conclusion : As shown above, according to assessments on China's PTD programs, the PTD Theory is being applied to actual public health programs with highly effective results. Hence, it can be seen that such attempt could also be implemented in Korea as part of a scheme for promoting health by means of Korean medicine health promotion programs. However, further researches into concrete implementation schemes will have to be developed in the future as medical systems are different in Korea from in China.

• 한국전기전자재료학회논문지
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• 제27권5호
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• pp.307-311
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• 2014

Because of a waveguiding effect and total internal reflection caused by a difference in refractive indices, only 20% of generated light is emitted to the air and the rest is trapped or absorbed in the device. An improvement of outcoupled efficiency of organic light-emitting diodes was studied using a microlens array. Mold of microlens array was fabricated by using photo-lithography with the AZ9260 photoresist, and the microlens array was formed onto the glass substrate using the UV curing agent named ZPU13-440. Device structure consists of microlens/glass/ITO/TPD/$Alq_3$/LiF/Al. It was found that there is an improvement of external quantum efficiency by about 20% at the same current density for the device with the microlens array compared to that of the reference one. Simulated outcoupled efficiency shows the improvement by about 20% for the device with the microlens array compared to that of the reference one. These results are consistent with the experimental ones.

• 동의생리병리학회지
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• 제23권2호
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• pp.278-287
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• 2009

Ji-San, the founder of HyungSang medicine, emphasized food intake and detoxification by stating, "Korean medicine begins with detoxification." Toxin accumulates in one's body unless the internal and external conditions stay in their harmony. The accumulation of toxin is also caused by western medication or one-sided diet, and detoxification should be considered in those cases. HwangRyunHaeDok-Tang reduces fire and heat, and the lesion is likely to locate in the upper body. BangPoongTongSung-San can be used for systemic disease. IkWoon-San also reduces fire and heat but mainly focuses on promoting urination. InSamPaeDok-San has an effect of curing the external symptoms of SangHan(傷寒), in addition to detoxification. SeoGakJiHwang-Tang, SoDok-Eum, and SeoGakSoDok-Eum can resolve the heat-toxin when it is located on the surface. SibJeonDaeBo-Tang enhances the detoxifying function of human body. GhamDu-Tang and JaGeum-Jung have a general effect on detoxification.

• Composites Research
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• 제30권6호
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• pp.371-378
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• 2017

본 연구에서는 대표적인 열경화성 재료인 에폭시 기지의 흡습탄성 거동을 예측하기 위해 분자동역학 전산모사를수행하였다. 고분자 복합재가 오랜 시간 동안 흡습환경에 지속적으로 노출될 경우, 거시적 물성의 저하가 발생하기 때문에 복합재의 내구설계 측면에 있어 흡습노화 현상에 대해 분자스케일적으로 접근하는 방법은 매우 중요하다. 본 연구에서는 $EPON862^{(R)}$ 수지와 아민계 Triethylenetetramine (TETA) 경화제로 비정질 에폭시 분자모델을 구성하였으며, 각각 30과 90%의 가교 상태에서 수분 흡수 유무에 따른 물성변화를 관찰하였다. 건조상태의 에폭시와 수분이 4 wt% 포함된 에폭시 단위셀에 대한 평형 및 비평형 앙상블 전산모사 과정을 통해, 에폭시의 수분팽창계수, 응력-변형률 선도 및 탄성계수 그리고 침투된 수분의 수지 내 확산계수를 예측하였다. 또한 흡습된 구조와 그에 따른 물성변화의 상관관계를 규명하기 위해, 자유체적 변화 및 흡습에 따른 에폭시 수지의 비결합 포텐셜 에너지 변화를 관찰하였다.

• 한국방재학회 논문집
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• 제7권2호통권25호
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• pp.35-44
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• 2007

일반적으로 유동성 뒤채움재는 모래, 플라이애쉬, 물과 소량의 시멘트를 혼합하여 이용한다. 플라이애쉬는 재활용재료로서 최근에 재활용 활용도가 매우 높아, 이를 대체할 대체제로서 해양준설토를 이용하였다. 해양준설토를 이용한 유동성 뒤채움재의 특성을 비교하기 일반바다모래를 이용한 혼합물을 이용하였다. 해양준설토를 이용한 유동성 뒤채움재의 흐름특성, 경화특성 및 일축압축강도 특성을 평가하였다. 유동성 뒤채움재의 초기 공용성평가를 위해 최적의 배합비에서 3일 양생한 시료의 강도 특성을 이용하였다. 시간에 따른 유동성 뒤채움재의 점착력과 내부마찰각을 평가하였다. 또한 차량하중에 의한 침하량을 평가하기 위하여 크리프시험을 수행하였다. 이동용 FWD를 이용하여 혼합재료의 탄성계수를 역산하였다. 이러한 실험결과로부터 해양준설토를 이용한 유동성 뒤채움재의 공학적 특성은 도로하부 지하매설물용 뒤채움재로서 충분한 것으로 판단되었다.

• 동의생리병리학회지
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• 제16권3호
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• pp.557-562
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• 2002

The present study was made with the aim of finding out the Kamihaepyoijin-tang's effect on the allergic asthma using the Egg-White Implant(EWI) method model recommended by de Siqueira et al. Kamihaepyoijin-tang has widely been prescribed and used in Oriental Medicine for controlling and curing of cough, asthma, nasal obstruction. Previous studies have demonstrated that Kamihaepyoijin-tang had analgesic, anticonvulsive effects. But it is uncertain whether Kamihaepyoijin-tang could inhibit the allergic reaction of rats with experimentally induced allergic asthma using EWI method. With such aim. the respiratory patterns and eosinophil infiltration in the tracheal mucosa of the rats were mainly observed. The results were summerized as follows ; 1. The frequency of malformed respiratory patterns in Kamihaepyoijin-tang treated groups were decreased as compared with the control group. 2. The Ratio of malformed respiratory patterns in Kamihaepyoijin-tang treated groups were significantly decreased as compared with the control group(p<0.02). 3. The eosinophil infiltration in Kamihaepyoijin-tang treated groups were decreased as compared with the control group. 4. The eosinophil infiltration that inside of trachea tissue in Kamihaepyoijin-tang treated groups were significantly decreased as compared with the control group(p<0.05). Depending upon above results, it is considered that Kamihaepyoijin-tang has the inhibitory effects on the allergic asthma of rats and suggested that it could be used in relieving patients of the symptoms which are caused by allergic asthma.

• 동의생리병리학회지
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• 제22권2호
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• pp.277-281
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• 2008

The objectives of this study lie in theoretical establishment of Bobee-tang for curing the asthenic syndrome of spleen through analyzing the component medicines and combination principles of Hyeongok's Bobee-tang, and furthermore, maximizing the clinical use of Bobee-tang. This study analyzed the component medicines and combination principles of Hyeongok's Bobee-tang based on the theory for properties and tastes of herbal medicines from the ${\ulcorner}$Yellow Emperor's Canon of Internal Medicine${\lrcorner}$, the theory for principal herbal medicine, assistant herbal medicine, adjuvant herbal medicine, dispatcher herbal medicine, and the five elements doctrine. Hyeongok's Bobee-tang is an odd prescription, composed of 7 kinds of ingredients : No.1 Radix Ginseng (2don;7.5 g), No.2 Rhizoma Atractylodis Macrocephalae (1don;3.75 g), No.3 Carapax Et Plastrumtestudinis (1don), No.4 Concha Ostreae (1don), No.5 Cortex Cinnamomi (1don), No.6 Rhizoma Zingiberis Praeparatae (1don), and No.7 Radix Glycyrrhizae (1don). First, to cure the asthenic syndrome of the spleen, the methods of invigorating the spleen and the heart, and purging the liver should be used according to the five elements doctrine. Secondly, herbal medicines appropriate for those treatment methods should be chosen according to the theory for properties and tastes of herbal medicine and thirdly, the combination of those herbal medicines should be carried out according to the theory for principal herbal medicine, assistant herbal medicine, adjuvant herbal medicine, dispatcher herbal medicine. As a good example, Hyeongok's Bobee-tang is combined according to the above theories. In conclusion, this formula was created by applying to the theory for properties and tastes of herbal medicines.

• 구강회복응용과학지
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• 제22권3호
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• pp.211-220
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• 2006

Need of porcelain-repair system is largely demanding as dental porcelain restorations are increased in clinical dentistry. This study investigated shear bond strength of commercial porcelain-repair systems on dental porcelain and their reliability. Experimental groups were as follows; Group A Super Bond C&B, Group B Porcelain repair kit, Group C Ceramic repair, and Group D Spectrum system as a control. Porcelain disks were fired and embedded in epoxy resin. Porcelain surface were ground using 220 grit SiC disk, then cleaned in ultrasonic bath. Then porcelain specimens were treated with each repair system. A clear polystyrene cylinder 3.5 mm in internal diameter was filled with composite resin. Then the resin cylinder was polymerized with a visible light curing unit. Thirty one specimens at each group were prepared and stored at $37^{\circ}C$ distilled water for 48 h. Specimens were tested in an Instron testing machine according to ISO TR 11405. Mean shear bond strength and standard deviation of each group was $15.7{\pm}4.1MPa$ (Group A), $12.8{\pm}4.9MPa$ (Group B), $7.2{\pm}3.0MPa$ (Group C) and $9.6{\pm}2.2MPa$ (Group D). ANOVA and Tukey HSD post-hoc test showed that there were significant differences between groups (p<0.05). Data of bond strength were analyzed with two-parameter Weibull distribution. Confidence interval of Weibull modulus (m-parameter) at 95% of Group A (3.5-6.3) and Group D (3.6-6.0) were significantly higher than Group B (2.2-3.7) and Group C (2.0-3.4). There was little correlation between mean shear bond strength and Weibull modulus. Results indicated that acid-etching of porcelain surface increased porcelain-resin shear bonding strength.