• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
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• pp.177-179
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• 2005

In Korean Power Market, Cost-based Bidding Pool is maintaining the present condition because restructuring of electricity industry is holding. When this market is designed, Settlement rules for Pumped-storage power plant made unfairly by other power plants. These rules were considered contribution of Pumped-storage power plant to network operation. by the way, there are some discussion about Settlement rules modification. so in this paper, we calculated financial effect of power plant by modified rules. And when we modify market rules, we can offer numerical information.

• 농촌계획
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• 제20권3호
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• pp.1-9
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• 2014

This study is to find out vitalization plan of rural village festival through field survey and in-depth interview. Festival vitalization plans were suggested for each of four steps. The results are as follows: (1) preparing stage : disambiguation of supporting festival, adjustment of selecting times & improvement of selecting index in supporting festival, support of planning & managing ability, and systematization of festival consulting team. (2) planning stage : supporting differentiated festival program development, and public relations of rural village festival. (3) operating stage : flexible utilization of supporting budget and systematization of festival supporters operation. (4) ending stage : holding a workshop to share successful festival cases.

• 한국기계가공학회지
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• 제12권5호
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• pp.94-101
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• 2013

Injection molding process is one of the most important methods to produce plastic parts with high efficiency and low cost. The objective of this study is to implement the best plastic injection molding process for LED TV speaker frame. Moldflow analysis and simulation of plastic injection molding process were carried out in order to predict optimal modeling operation conditions and then injection molded part was produced various type of resin temperature, filling time and injection pressure variation. the result was that the best injection molding condition is set as 60bar pressure, 2sec filling time and $310^{\circ}C$ degree. The study result would be useful to variety of plastic injection molding process.

• 소성∙가공
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• 제16권1호
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• pp.36-41
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• 2007

Thermoplastic elastomer(TPE) can be recycled and molded such as commercial thermoplastic. Therefore TPE has being widely applied on automobile, household and etc. in these days. This study shows the variation of mechanical properties and shrinkage on TPE moldings for variation of injection molding conditions such as injection pressure, holding pressure, melt temperature, mold temperature and etc. Mechanical properties in relation to tensile strength, hardness and shrinkage in connection with precision dimension of part are investigated. The tensile strength and shrinkage of the experimental TPEs are mainly influenced by injection pressure and melt temperature. All injection molding conditions scarcely affect on hardness. To verify the variation of tensile strength and shrinkage, morphology of TPE molding was scanned by the SEM. The morphology showed that as the melt temperature increased, the rubber particles on the TPE became smaller and widely were dispersed. This behavior of rubber particles influenced on the increase of tensile strength.

• 한국세라믹학회지
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• 제46권4호
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• pp.397-404
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• 2009

Using rice husk ash as silica, the influence of the firing temperature and holding time on the color intensity of Pr-$ZrSiO_4$ pigments were investigated. The Pr-yellow pigments were calcined at 500, 700, 800, 900, 950, 1000, $1100^{\circ}C$ in a ceramic method. The synthesized pigments were characterized by DT-TG thermal analysis, X-ray diffraction, UV-Vis spectroscopy, and SEMEDAX analysis. The relationship between the zircon phase-formation growth and Pr-yellow color development was evaluated and the optimum firing conditions were determined. The color of the pigment samples was characterized on the grounds of the Commission Internationale de l'Eclairage (CIE) standard procedure (CIE $L^*a^*b^*$ measurement) after an application on the bisque ceramic tile.

• 한국환경과학회:학술대회논문집
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• 한국환경과학회 2003년도 International Symposium on Clean Environment
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• pp.135-138
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• 2003

Based on solid phase extraction, gas chromatography and mass spectrometry procedure for determining phenol and its derivatives in natural water was presented. In solid phase extraction, three types of techniques using solid phase adsorption material were treated with acid and salt, and converted second portion of acetyl derivatives. Under the these condition, extraction efficiency and detection ability dependent on extraction methods were discussed. Obtained results using optimized solid phase extraction techniques showed more convenience, simplifier and lower cost than the conventional analytical methods with holding wide dynamic range and lower detection limits.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
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• pp.137-139
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• 2007

In optical disk drives, a conventional control method in the presence of surface defect is holding the previous tracking control command. It is known that the method has a long settling time. This paper proposes a new control method which reduces the settling time. An optical head generally has coupled dynamics between focusing and tracking servo system. We present how to compensate the coupled dynamics so that reduced settling time is achieved. It is verified by experiments that the proposed method brings an improved performance in the presence of surface defect as well as in the normal operating condition.

• 한국주조공학회지
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• 제20권6호
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• pp.407-418
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• 2000

The effect of various factors on the results of degassing of AC4C aluminum alloy melt by using rotary degasser were investigated. The difference between the effects of nitrogen gases of commercial pure and high purity grades on the degassing results was not significant. The optimum degassing condition was obtained. The effect of holding and degassing temperature was not significant, either. The result of degassing was deteriorated by the modification treatment of eutectic silicon, meanwhile improved by the grain refining. The effect of the latter was stronger than that of the former when the melt was treated simultaneously. The volume fractions of hydrogen porosity of the castings obtained from the molds with water moisture such as natural and green sand molds were much higher than those from the molds without that such as pep-set and $CO_2$ molds.

• 동력기계공학회지
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• 제5권1호
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• pp.80-88
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• 2001

The spot welding method has been used in the joining of structures, automotive body, railway carriage, aircraft, household electric appliances, precision parts etc., because of brief working, easy automation, available mass production, and convenience. In this paper, the effects of welding conditions on the fatigue life and the prediction of fatigue life based on fracture mechanics theory of spot welded joint were investigated. Fatigue tests were conducted with the tensile-shear specimens welded in the various current using cold rolled steel sheets. Fatigue life of spot welded joint was predicted and compared with experimental results. Using FEM(finite element method), we analysed the distribution of stress and the condition of deformation on the environments of nugget.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 추계학술대회 논문집
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• pp.265-268
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• 2005

Thermoplastic elastormer (TPE) has many advantages such as high flexibility, high elasticity and high elongation, etc. TPE is easily molded such as plastic materials, therefore, many TPE parts are applied as home appliances and mechanical parts. However, if TPE is once molded, its mechanical properties are changed by injection molding conditions such as melt temperature, mold temperature, injection pressure and holding pressure, etc. In this study, the influences of the injection molding condition on the mechanical properties of thermoplastic vulcanizates(TPVs), which is one of the TPE, were investigated. By the injection molding experiment, as increasing the melt temperature, the tensile strength, shrinkage and hardness decreased. By the scanning electron microscope (SEM) analyzing the TPVs' crystallization, the morphology was affected by the melt temperature.