• Cement
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• s.151
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• pp.55-61
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• 1999

• Agrochemical news magazine
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• v.24 no.6 s.189
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• pp.20-23
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• 2003

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.11a
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• pp.5-8
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• 1994

임상시험 guideline은 신약개발을 촉진하기 위하여 약사법 제 26조 제 6항 및 제 24조 제 8호의 규정에 의거하여 신약 임상시험의 안내서로 활용하게 하는데 있다. 임상시험은 특정약의 특정 질환에 대한 임상효과를 판정하기 위하여 시험약의 효과 및 부작용을 윤리적으로 타당한 과학적 시험을 통하여 시행하는 것이다. 특히 임상시험은 사람을 대상으로 하기 때문에 윤리적이고 과학적인 방법을 통하여 시행착오를 최소화하고, 피험자가 위험에 처할 가능성을 최소화하여야 한다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.9
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• pp.1253-1258
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• 2012

In the present study, we investigated the effects of Rubus coreanus Miquel (RCM) on memory ability of senescence-accelerated mice (SAM). Prone 8 strains of SAM mice (SAMP8), which is a useful animal for investigating the mechanism of brain aging and senile dementia, were fed a diet containing 100 mg/kg body weight/day of RCM for 8 weeks. Memory ability of mice was examined by using passive avoidance test and Morris water maze test. SAMP8 mice showed remarkable memory impairment compared with senescence-resistant 1 strains of SAM (SAMR1). RCM significantly improved memory ability of SAMP8 mice. In addition, acetylcholineasterase activities decreased in the brain of SAMP8 mice treated with RCM. Taken together, these results suggest that RCM may act as an acetylcholineasterase inhibitor, thereby improving senescence-related memory impairment.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.357-358
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• 2010

This study was performed an evaluation of chloride attack resistance properties of marine concrete by accelerated deterioration test of artificial seawater. As the results of study, when considering the compressive strength and chloride ion penetration of concrete, the proper type to improvement of chloride attack resistance is thought to marine cement.

• Journal of the Korea Concrete Institute
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• v.15 no.4
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• pp.541-548
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• 2003

This study is to investigate the temperature curve and development of compressive strength due to the curing conditions and to evaluate the optimum curing condition of test specimens showing the same development of strength to that of real structures in cold weather. The results of temperature curve with curing conditions in mock-up tests showed the trend of decrease plain concrete with insulation form, plain concrete with heating, concrete with accelerator for freeze protection, and control concrete in turn. The strength development of plain concrete of inside and outside of shelter showed the very slow strength gains due to early freezing, but that of concrete with accelerator for freeze protection showed the gradual increase of strength with time. From this, it is clear that accelerator for freeze protection has the effects of reducing the freezing temperature and accelerating the hardening under low temperature. Strength test results of small specimens embedded in members and located in insulation boxes at the site are similar to that of cores drilled from the members at the same ages, thus it is clear that these curing methods are effective for evaluation in-place concrete strength.

• Tunnel and Underground Space
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• v.32 no.6
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• pp.363-372
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• 2022

Precast concrete is an effective method to increase the construction quality and construction speed by optimizing and making the manufacturing conditions similar. In order to more effectively produce a fireproof material-integrated precast duct slab, the purpose of this study was to determine whether the fire resistance performance of the fireproof layer is maintained when a method of increasing the curing rate using a hardening accelerator is used. As a result of performing a fire resistance performance test on specimens classified according to whether or not the hardening accelerator was included, increase of temperature inside the specimen was high in the specimens using the hardening accelerator, and the section loss of the fireproof layer occurred locally on the surface exposed to fire heating. In conclusion, it is judged that the fireproof layer in the case where the strength at 3th day of age is gained within 1 day curing age using a hardening accelerator does not guarantee sufficient fire resistance performance in the conditions used in this study.

• Applied Chemistry for Engineering
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• v.4 no.1
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• pp.178-187
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• 1993

Degradation of the starch-polyethylene composite film by an activated sludge treatment and a soil burial test was examined. The treated films had deformed structures which were resulted from the removal of starch during the treatments. The added auto-oxidant caused the degradation of the polyethylene matrices and the crosslinking reactions after the oxidation of polyethylene chains as well. As a result of soil burial test, the degradation reaction of the composite film containing corn oil as an auto-oxidant was, however, prevalent : number- and weight-average molecular weight of polyethylene decreased, while the molecular weight distribution increased.

• Proceedings of the Korean Reliability Society Conference
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• 2000.04a
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• pp.81-87
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• 2000

최근 신뢰성 가속 시험 분야에서 제품의 잠재 또는 취약 부위를 단기간에 효과적으로 검출할 수 있도록 개발된 HALT(Highly Accelerated Life Test) 기술을 당사에서 생산 중인 영상제품에 적용하였다. 적용 결과 HALT는 기존의 보증용 가속 시험에서 추구하는 고장 데이터의 통계적인 수명 예측이나 고장률 추정의 절차를 따르지 않고도 한계 스트레스 시험을 이용하여 제품의 잠재적인 취약부위를 단시간에 효과적으로 촉진하고 들춰 내어 전자 제품에 적용할 수 있는 유용한 가속 스트레스 시험 기술임이 입증되었다.

• Journal of the Korea Institute of Building Construction
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• v.15 no.3
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• pp.265-271
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• 2015

This study is intended to produce a PC (Precast Concrete) member without a steam curing process in developing the high early strength concrete satisfying the condition of 10MPa in compressive strength at the age of 6 hours, and is intended to ensure economic feasibility by increasing the turnover rate of concrete form. Hence, high early strength cement with high $C_3S$ content and the hardening accelerator of powder type accelerating the hydration of $C_3S$ was used. And the properties of concrete were evaluated according to the hardening accelerator mixing ratio (0, 1.2, 1.6, 2.0). No big difference was found from the tests of both slump and air content. When 1.6 % or higher amounts of the hardening accelerator were mixed, the compressive strength of 10MPa was achieved at the age of 6 hours. From the test results of autogenous (drying) shrinkage and plastic shrinkage, it can be seen that there was a difference according to hydration reaction rate due to the addition of the hardening accelerator. However, it was shown that no problem arose with crack and durability. And it was shown that resistance to freezing-thawing, carbonation, and penetration were excellent.