• 대한기계학회:학술대회논문집
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• 대한기계학회 2002년도 학술대회지
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• pp.407-410
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• 2002

A series of steam explosion experiments using real core materials of $ZrO_2$ and corium(a mixture of $ZrO_{2}\;and\;UO_{2}$) has been performed to evaluate the risk of steam explosion load in nuclear power plants. Surprisingly, spontaneous steam explosions are observed far both materials, which have been thought to be inexplosive so far. The dynamic pressure and morphology of the debris clearly indicate the evidence of an explosion. The experimental results also indicate that $ZrO_2$ is more explosive than corium.

• Corrosion Science and Technology
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• 제4권5호
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• pp.207-210
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• 2005

Coating performance of various coating systems including chlorinated rubber and epoxy/urethane used most for steel structures of highway in Korea, was evaluated by exposing test specimen to complex deterioration factors such as ultraviolet ray, moisture, freeze-thaw cycle and salt. Deteriorated specimens were evaluated by chalking and rust grades according to ASTM, and measurement of color differences and adhesion. In overall coating performances such as corrosion resistance, photochemical stability, and adhesion, ceramic/ urethane, moisture-curable urethane/ urethane, etc. were superior. As for other coating materials tested in this study, superior materials against certain deterioration factors may be inferior against other factors. Accordingly, in order to select suitable maintenance coating materials for the use, it is thought that investigation of suitability through experiment should precede selection of materials, especially for unusual coatings or paints.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 춘계학술대회 논문집
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• pp.792-795
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• 2000

The magnetic assisted finishing thought to be one of the potential methods for the automatic polishing process. In this study, magnetic assisted finishing process was experimentally attempted to polish the intrnal surface of the cylindrical tube. The newly developed magnetic tool was used, and its polishing performance exmined. From the experimental results, it is found that i ) the newly developed tool is suitable for intrnal surface finishing of the tube. ii ) the surface roughness of 0.9~1${\mu}{\textrm}{m}$Rmax before polishing is improved to the value of 0.2 ${\mu}{\textrm}{m}$Rmax in the finishing experiment of stainless steel STS3602L tube in 6 minutes finishing time.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 반도체 재료 센서 박막재료 전자세라믹스
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• pp.34-37
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• 2004

Recently advancing mobile communication tools and I.T industry, semiconductor device is requested more integrated, faster operation time and more scaled-down. Because of these reasons semiconductor device is requested multilayer interconnection. For the multilayer interconnection chemical mechanical polishing (CMP) becomes one of the most useful process in semiconductor manufacturing process. In this experiment, we focus on understand the characterize and improve the CMP technology by control of slurry flow rate. Consequently, we obtain that optimal flow rate of slurry is 170ml/min, since optimal conditions are less chemical flow and performance high with good selectivity to Ta. If we apply this results to copper CMP process. it is thought that we will be able to obtain better yield.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.49-51
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• 2007

It is as result that study to apply mini magnet nerve curer in peripheral nervous system disease treatment. Design and embodied action power and Control Unit in cylinder form of magnet roof object firstly. Yielded service area about special quality of probe of roof object cylinder style and treatment area dimension and distance of treatment pulse secondly. Embody pulse forming course energy value by Probe's form by third, could embody treatment pulse by disease. Specially, through a special quality experiment, saved Damping pulse torn and treatment pulse form etc. variously. Lately, embodied this to aid a little in disease treatment that follow that there is no invasion that there is no stimulation by medicine development. Go amplitude treatment pulse (traditional magneto-therapy of greatly great that strong) does curative effect greatest at short time and becomes thought that demand is magnified greatly at the future in this research.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.824-831
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• 2005

A model test was carried out, in order to verify the hydrodynamic performances of public 30 feet class sailing yacht. In the initial design stage, the performances and the running attitude of sail yacht including the hull form and sail plan, appendages were estimated by VPP, from which made the representative test conditions. A new experiment system such as captive model device was composed because the running attitude could be changed by wind conditions. The test results show that the minimum resistance is generated in the heeling 20 degree, which was expected in the initial design stage. It is thought to be the useful informations that the keel has an effects on hydrodynamic forces and resistance differences between the upwind and the downwind condition. Also this paper is associated with the state-of-the-art of calculating sailing yacht performance as this is performed in velocity prediction program (VPP). The VPP results shows a typical shape of a sailing yacht and the designed yacht has the best performance at 120 degree angle of true wind with 20 knots.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1536-1541
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• 2003

The model of azimuth driving servo system with a flexible antenna in a microwave seeker has been derived in this paper. The validity of the model is verified by comparing the result of the model with that of experiment. It is found that one should consider an antenna as a flexible body in case of modeling the dynamics of the microwave seeker. It is also known that the effect of reducing backlash magnitude for extending the bandwidth in the system with a flexible antenna is smaller than that in the system with a stiff antenna. It is thought that the model-based design optimization of the microwave seeker will become possible by virtue of the derived model, when a weight reduction and a bandwidth extension are required.

• 대한수의학회지
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• 제20권2호
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• pp.135-141
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• 1980

This experiment was carried out to investigate of the early pregnancy diagnosis by finger pressure method, mucus smear method and rectal palpation method in 169 heads of pregnant dairy cow. 1. Pregnancy diagnostic rate of previous, middle and late period of pregnancy by finger pressure methods were 87.3%, 82.0% and 70% respectively. 2. Pregnancy diagnostic rate of previous, middle and late period of pregnancy by mucus smear methods were 83.1%. 94.9% and 95.0% respectively. 3. Pregnancy diagnostic rate of previous, middle and later period of pregnancy by rectal palpation methods were 83.1%, 96.1% and 100% respectively. 4. Pregnancy diagnostic rate of early pregnancy by finger pressure method, mucus smear method and rectal palpation method were 86.7%, 86.8% and 66% respectively. 5. Accordingly, finger pressure method in pregnancy diagnosis is thought to be recommendable because this early diagnostic means are simple with accurate results.

• Journal of the Korean Wood Science and Technology
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• 제28권4호
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• pp.1-9
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• 2000

This experiment was accomplished to investigate antioxidative activity of Korean mistletoe by organic solvents partitioning of methanol extact of 3 Korean mistletoes, fractionationing on column chromatography, and evaluation the reduction of a free radical ${\alpha}$,${\alpha}$-diphenyl-${\beta}$-picrylhydrazyl. Butanol partition of Loranthus yadoriki MeOH extract showed higher electron donating ability than ${\alpha}$-tocopherol. It was thought phenolic compounds including gallic acid account for antioxidative activity, on execution sub-fractionation, electron donating ability evaluation, and GC/MS analysis, but further studies on what are major actives must be investigated exactly.

• 대한한의학회지
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• 제21권1호
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• pp.40-44
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• 2000

Objectives: This study was conducted to find out whether herbal medication during pregnancy causes any deformity in the unborn fetus. Methods: Thirty-five gynecological outpatients of KyungHee Univ. Oriental Hospital (1996. 10 - 1999. 2) who had taken herbal medication during pregnancy were questioned about duration of pregnancy at the moment, chief complaints, kinds of herbal medicine taken and its dosage and they were asked to answer the questionnaire over the phone about duration of pregnancy at the time of delivery, the newborn’s weights, delivery methods and the condition of deformity. Results and conclusions: The results of this experiment in which 35 pregnant women with the experience of herbal medication during pregnancy confirm that herbal medication during pregnancy does not cause any deformity to the newborn. It is thought that more studies through clinical follow-up and experiments are needed in the future.