• 한국정밀공학회지
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• 제21권12호
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• pp.37-43
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• 2004

The performance of magnetic abrasive finishing fur surface is evaluated by the characteristic curve. The characteristic curve is generated by experiment in surface finishing. For experiment, new magnetic inductor is designed and manufactured. 15 kinds of powders are provided to find the relationship between powder characteristic and finishing performance. As powder, Fe-TiC. Polymer-TiC and Fe-NbC are used with different size. The size of abrasives and location are also important factor for the performance. From characteristic curve, two index are obtained, which specify the initial finishing performance and endurance of finishing performance. It is proved that the performance index can be applied to select proper powder for efficient deburring. It is shown that the characteristic curve can be used as good tools for evaluating powder performance in surface finishing and deburring.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 가을 학술발표회 논문집
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• pp.75-80
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• 2002

This study is to investigate the characteristic on the resistance of chloride infiltration concrete containing limestone powder The variables are the substitution ratio of slag powder and limestone powder. In order to study the effect slag powder and limestone powder, all mixtures were prepared at a fixed water/cement ratio, slump, and entrained air quantity. As results show that the strength and the resistance of chloride infiltration in concrete substitution 10%, 20% limestone powder, and 30%, 40% slag powder are positive.

• 한국세라믹학회지
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• 제41권8호
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• pp.588-592
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• 2004

Dynamic Milling (DM) 방법에 의한 $UO_2$ 분말의 특성 변화가 밀도에 미치는 영향을 조사하였다 분쇄시간(0∼8시간)의 증가에 따라 분말입자의 크기는 감소하며 둥근 형태를 지녔으며, 비표면적과 O/U 비는 증가하였다. 이러한 특성 변화에 의해 성형밀도는 증가한 반면에, 소결밀도는 감소하는 경향을 보였다. 소결밀도의 감소는 분말 분쇄과정에서 야기된 $UO_2$ 분말의 O/U 비의 증가가 주된 영향을 미친 것으로 사료된다.

• 한국조리학회지
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• 제23권3호
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• pp.174-185
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• 2017

The purpose of this study was to investigate the quality characteristics of fish paste added with different amounts (0%, 0.5%, 1%, 1.5%, and 2%) of spirulina powder. Specifically, moisture content, pH value, color value, texture value, total polyphenol content, DPPH radical scavenging activity, and sensory evaluation were measured in the samples. The moisture content of the fish paste added (0.5%, 1%, 1.5%, and 2%) ranged from 68.60% to 69.03%, and the increased amounts of spirulina powder in the fish paste tended to decrease the pH value. For the Hunter color values, the L, a values of surface and inside of the fish paste decreased with increased amounts of spirulina powder. The b values of the fish paste increased with increased amounts of spirulina powder. In the texture meter test, the hardness, gumminess, and adhesiveness decreased with the increased amounts of spirulina powder, and chewiness of group adding spirulina powder was measured lower than control. Springiness of the fish paste did not appear statistically significantly different among the samples according to the increased amounts of spirulina powder. Total polyphenol content of fish paste added with spirulina powder increased with increased amounts of spirulina powder, and DPPH radical scavenging was heightened according to increased amounts of spirulina powder. In sensory evaluation, the addition of 1% spirulina powder had the best score in odor, texture, taste, and overall preference. These results suggest that spirulina powder can be applied to fish paste to increase quality, preference, and functionality.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.935-938
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• 2001

This paper reports the relation of concrete setting characteristic and lateral pressure in mass concrete wall such as side wall of LNG underground storage tank. In order to estimate the lateral pressure, initial setting time of low heat cement concrete with type of mineral admixture was measured for three concrete mixtures(W/P=41.6%) containing limestone powder, fly ash, and slag powder. As a result, the lateral pressure of the concrete containing limestone powder was the smallest than those of other concretes as well as the initial setting time.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2002년도 추계학술강연 및 발표대회
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• pp.11-12
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• 2002

• 한국분말재료학회지
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• 제2권1호
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• pp.29-35
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• 1995

In this study the calcined condition and characteristic of Cu-Ni-Zn ferrite powder were investigated. The Cu-Ni-Zn ferrite powder has been synthesized by the thermal decomposition of the organic acid salt. This process did not require a strict pH control and provided the uniform composition and fine powder with about 0.3 $\mu\textrm{m}$. The XRD diffraction pattern of this powder showed about 50% spinel phase. The optimum calcination was found to be done at $700^{\circ}C$ for one hour. After the calcination, the amount of spinel increased to 90%. The distribution of the particle size showed bimodal peaks, one was about 0.5 $\mu\textrm{m}$ and the other was about 20 $\mu\textrm{m}$. The large particles of 20 $\mu\textrm{m}$ were the agglomeration of fine Particles. The mean Particle size of the powder was about 0.4 $\mu\textrm{m}$. The powder was compacted under 100 MPa pressure and sintered at 1100~ $1250^{\circ}C$ for one hour in air. The density of ferrites specimen was a function of the sintering temperature. The higher the temperature, the denser the ferrite. The maximum relative density of the sintered ferrite was about 93% at $1250^{\circ}C$. The grain size of sintered specimen at $1200^{\circ}C$ was 5 $\mu\textrm{m}$ and homogeneous.

• 열처리공학회지
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• 제34권2호
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• pp.60-65
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• 2021

In this study, the effect of pressure type and foaming agent on the microstructural change of Al foam produced by powder compact processing was investigated. Better foaming characteristic is easily obtained from extrusion process with strong plastic deformation and preheating than that by uniaxial pressing with preheating. In current powder compact foaming process using TiH2/MgH2 mixture as a foaming agent, a temperature of 670℃ and addition of 30% MgH2 in TiH2 foaming agent was chosen as the most suitable foaming condition. The aluminum (Al) foams with maximum porosity of around 70%, relatively regular pore size and distribution were successfully produced by means of the powder metallurgy method and extrusion process.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.294-295
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• 2006

Varistor fabricated with ZnO nano-powder was studied about the characteristic of energy capability in this paper. ZnO nano-powder varistor were sintered in air at $1050\;^{\circ}C$. The electrical properties and residual voltage of ZnO nano-powder varistor were obtained. Our ZnO nano-powder varistor has about 3 times of electric field at varistor voltage as compared with commercial ZnO varistor fabricated with micro-powder. In the current impulse withstand test, our nano varistor has had better performance than micro varistor. To analysis energy capability take infrared images for pyrexia distribution of each varistor. ZnO Nano-powder varistor has shown much quick response property because of increasing effective cross-section.

• 한국전기전자재료학회논문지
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• 제22권3호
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• pp.210-217
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• 2009

Insulated methods of compact bus duct has been applied a way of coating Epoxy powder. The problem which is caused by degradation during operation is very important in severe environment. Therefore, this study compared and verified many kind of properties ; electrical breakdown by thermal and water aging, v-t characteristic, arc discharge, mechanical properties, bending test and cross cut. Sample D was stable before the $T_g$ to be about $7{\sim}10 %$ decrease in the breakdown test according to temperature change. In case of V-t and arc discharge, it had been kept up suitable characteristic. Also, in case of electrical and mechanical characteristic, both sample D and A have excellent capacity.