• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2005년도 춘계학술대회 논문집
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• pp.473-476
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• 2005

Today's manufacturing industry is facing challenges from advanced difficult-to-machine materials (WC-Co alloys, ceramics, and composites), stringent design requirements (high precision, complex shapes, and high surface quality), and machining costs. Advanced materials play an increasingly important role in modem manufacturing industries, especially, in aircraft, automobile, tool, die and mold making industries. The greatly-improved thermal, chemical, and mechanical properties of the material (such as improved strength, heat resistance, wear resistance, and corrosion resistance), while having yielded enormous economic benefits to manufacturing industries through improved product performance and product design, are making traditional machining processes unable to machine them or unable to machine them economically. In this paper, mechanical characteristic evaluation test of fine powder type WC-Co alloy was accomplished to obtain clear data for miniaturized special die parts machining with high reliability and high quality.

• Journal of Electrical Engineering and Technology
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• 제13권1호
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• pp.379-386
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• 2018

A heat-sink has been widely used to cool down the heat generated from an electronic device, but it can bring unwanted electromagnetic radiation which may cause EMI problems. We propose a systematic method to reduce the electromagnetic radiation by using the multiple grounding technique based on the grounding criteria and the theory of characteristic mode analysis. Our proposed method provides the insight to find the specific grounding positions which can be effectively reduced the radiation from the heat-sink. Numerical experiments are accomplished to validate this approach.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 C
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• pp.1697-1698
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• 2006

When the coil with alternating current approaches to the conductor the eddy current flows in conductor. Eddy current is concentrated on the conductor surface and decrescent because of skin effect. In this paper investigated eddy current characteristic that is happened in conductor. Analyzed characteristic using electromagnetic field finite element analysis program that is commercialized to analyze value of eddy current and penetration depth. Analyzed creation value of eddy current and penetration depth in conductor that change operation frequency and the material of conductor, coil outside diameter, inside diameter, position, type of conductor from analyzed eddy current characteristic. The results, using distribution of eddy current and penetration depth data is that will help to forecast ECT(Eddy Current Testing), Eddy current application and use field, eddy current loss.

• 한국정밀공학회지
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• 제12권12호
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• pp.157-164
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• 1995

Straight belvel gear is used mainly for steering system, final reduction and differential gear in the automobile. The more high load, high velocity driving bevel gear, the more unsafe and unpleasant. In thid study, we get a kinematic equation by modelling straight bevel gear pair with simple elastic system, the dynamic characteristic analysis about this system, we got the dynamic load factor of tooth surface. Comparing the value of dynamic load factor by calculation with the measured value of Terauchi's experimental results is similar. We think it useful to analysis the vibration and the noise of straight bevel gear in operation with the analytic method of dynamic load of straight bevel gear using in this study.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.467-468
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• 2012

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2013년도 춘계학술대회 논문집
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• pp.166-166
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• 2013

유체 플라즈마 공정은 금속 나노입자를 제조하는데 있어서 혁신적이고 친환경적인 공정 방법의 하나이다. 본 연구에서는 유체 플라즈마 공정을 통해 젤라틴 기지재 내에 은 나노입자를 합성하였고, 합성 된 용액은 동결건조를 통해 3D scaffold 형태의 생체복합체로 제조하였다. 이렇게 제조된 생체복합체의 물리적 특성 및 생물학적 특성 평가를 통해 생체복합체의 효율성과 항균 효과가 뛰어남을 확인하였다.

• 연구논문집
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• 통권23호
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• pp.5-13
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• 1993

The present work deals with the theoretical prediction of static & dynamic characteristic of annular type externally pressurized thrust air bearings with metal-sintered porous media. For the evaluation of surface loading effect by machining, it is assumed that the flow at the porous surface is dominant and which is equivalent to the flow through orifice. Finite different method with over-relaxation method is used to solve the numerical problems. The influences of radius ratio, supply pressure and squeeze number on performances are investigated, as the results. The results of this study can be used to predict the optimal running condition and stable realm of porous bearings.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 추계학술대회 논문집
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• pp.29-30
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• 2006

• 충청수학회지
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• 제28권2호
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• pp.243-249
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• 2015

Let X be a closed surface for which the Euler characteristic $_{\mathcal{X}}(X)$ is negative, and let $f:X{\rightarrow}X$ be a self-map that is not surjective. In this short paper, we prove that we can compute the Nielsen number of f, N(f), under some algebraic conditions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.462-464
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• 1990

We report the development of a surface discharge preionized KrF discharge Laser with a new type of high-brightness Corona preionizer using a segmented columnar $BaTiO_3$ dielectric. This Laser characteristic was higher value than that obtained with the conventional corona preionizer using a glass, $Al_2O_3ceramic$, Kapton film, or a Teflon insulator.