• Journal of the Korean Ceramic Society
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• v.26 no.6
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• pp.789-794
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• 1989

The high-temperature strength of Ce-TZP was measured at 200, 650 and 100$0^{\circ}C$ by 4-point bending test. And its fracture behavior was observed by SEM. Below $650^{\circ}C$ of the temperature, where monoclinic fraction was almost zero, the decreasing rate of bending strength was relatively slow, but above this temperature, high temperature strength was largely decreased as a result of the decrease of stress-induced transformation of zirconia. The observation of fracture surface bended at 100$0^{\circ}C$ indicated that the fracture mode changed from intergranular-into transgranular-form with regardless of ceria contents.

• Journal of the Korean Ceramic Society
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• v.34 no.6
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• pp.601-610
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• 1997

In cofiring of multilayered alumina with tungsten, the change of camber with lamination condition was experimented and the effect of sintering shrinkage of alumina and tungsten was investigated. From the exact measurement of sintering shrinkage of tungsten thick film, as lamination pressure increased, the sintering shrinkage of alumina decreased but that of tungsten thick film was not changed. So it was though that the main factor which induced the sintering shrinkage difference between ceramics and metal with lamination condition was the change of sintering shrinkage of ceramics. In case of high lamination pressure, high green sheet density, the cofired specimen showed low camber due to low shrinkage difference between alumina and tungsten and there was a linear relation between camber and shrinkage difference. It was found that this shrinkage difference could change the thickness of tungsten film and the microstructure within via hole during cofiring.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1998.10a
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• pp.325-332
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• 1998

The use of air-supported membrane has considerable attention in recent years. There are, however, a number of problems in the behavior of these structures that have not been fully investigated. For example, the problem of local loafing on such membranes has not been analyzed yet. The paper presents an analysis of internal and external potential energy of a spherical air-supported membrane with vertical longitudinal axis, subjected to local loadings. An internal pressure value of the applied load is established at which tile potential of these structures change positive. During such change the loading portion of the membrane comes into work beyond stable state. The mathematical method is used throughout the paper in obtaining solution. For the mathematical modeling, two assumption are used. One is the theta's elimination and the other is the infinite condition. The paper is illustrating the examples of spherical air membrane dome subjected to local load.

• Proceedings of The KACE
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• 2018.01a
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• pp.137-140
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• 2018

대한민국의 대표적인 구기 종목 중 하나인 농구는 입문 시 기본 동작에 적응하고 기본 규칙을 이해하기 위해 많은 시간이 소비된다. 또한 기존 농구 학습 분야에서 평가 수행 시 평가 대상자의 실력을 정량적으로 도출하는 것이 힘들어 중 고등학교 체육교과의 수행평가에서 객관적인 평가가 이루어지기 힘들었다. 본 연구에서는 이러한 농구 학습의 한계점을 해결하기 위하여 3축 자이로 센서와 스위치가 적용된 웨어러블 시스템을 기반으로 농구 학습을 도와주는 동작인식 기법을 제안한다. 그리고 실험을 통하여 제안하는 동작인식 기법의 성능을 검증하였으며, 생활체육 활성화를 통한 국민 건강증진과 객관적인 수행평가 실현에 기여할 것으로 기대된다.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.119-120
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• 2006

In this paper, we suggest postal RFID adaptation model, tag data structure and code which can be used for real time trace and track of parcel processing and pallet management. This paper also shows postal RFID application system architecture and testbed based on the proposed tag data structure and code, and shows recognition performance of tag on parcel and pallet by speed and mounting tag material such as can, water, and paper using implemented postal RFID system for postal logistics. The contribution of this paper is to stimulate deployment of RFID technology for postal logistics service and SCM (Supply Chain Management).

• Journal of the Korean Ceramic Society
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• v.31 no.1
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• pp.31-38
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• 1994

To overcome the demerit of conventional forming method, new forming method, pressureless powder packing forming method, was investigated. This technique is performed by powder packing followed by the infiltration of binder solution. Various alumina powders were used as starting materials and the powders showing good packing condition through powder packing experiment were chosen. The green densities prepared by this new forming method with these powders were lower than those of specimens by pressing method, but, nearly same density was obtained in case of green body prepared with the powders having high packing density. The distribution of binder in a green body was homogeneous and it was possible to a complex shape form by this forming method.

• Journal of the Korean Ceramic Society
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• v.25 no.6
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• pp.615-622
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• 1988

To develope good slip and microstructure of Si3N4 the knowledge of the interaction of particles in liquid systems is required. In this work polyethyleneimines was tested as a stabilizer for Si3N4-water system. The stability of slip dispersed with polyethyleneimines was good over a wide range of pH and concentrated slips with low viscosity could be cast. This work comprises a systematic investigation including determination of electrical mobility in order to estimate the particle surface charge, determination of sedimentation rate, as well as measurements of the viscosity as a function of dispersants, pH and shear rates. The influence of deflocculation on the microstructure of slip cast Si3N4 was discussed.

• Journal of the Korean Ceramic Society
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• v.28 no.5
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• pp.415-421
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• 1991

Influence of Li2O.4B2O3 frit addition on the microstructure and thermal expansion properties of $\beta$-eucryptite ceramics was studied. With 1.0~10.0wt% frit addition, sintering temperature range was enlarged and densified body was obtained. Thermal expansion was increased from -6.67$\times$10-6 $^{\circ}C$-1 of pure sintered body to 1.03$\times$10-6$^{\circ}C$-1 of 6 wt% added body, but this increasement was accompanied by inhibition of thermal expansion anisotropy, so that improved microcracking property.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.11a
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• pp.597-600
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• 2002

새 천년이 시작하면서 자본주의의 새로운 기업 모델로 e-Biz가 각광받았다. 하지만 곧바로 사양되었으며, 이 시점에서 새로운 대안으로 떠오른 것이 바로 모바일 인터넷 비즈니스였다. M-Biz는 편재성(Ubiquity), 접근성(Reachability), 보안성(Security), 위치확인(Localiz ation), 즉시 연결성(Instant Connectivity), 개인화(Personalization)의 모바일 인터넷 장점을 이용하여 뚜렷한 수익모델로 가능해졌기 때문이다. 이런 모바일 컨텐츠 서비스는 정보제공(Information), Entertainment, 상거래(Transaction), 단문메시지 (Communication) 등을 현재 제공하고 있으며, 이러한 기능들을 현재 개발되고 있는 홈 오토메이션 시스템과 결합하여 새로운 형태의 홈 오토메이션을 기반으로 하는 모바일 서비스 지원 기법을 본 논문에서는 논하였다.

• IE interfaces
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• v.22 no.4
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• pp.302-311
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• 2009

It's very important to make an effective and optimized production schedule for the small-to-medium-sized factory which have high-variety low-volume manufacturing properties. And now people say that MES is very useful to make scheduling more effectively. But for small-to-medium-sized factory, it is very difficult to build MES system because of fewer infrastructures in the factory, and more to keep it's continuous maintenance and improvement. Therefore it is more important to systematize the production scheduling generation using simpler and easier tools like EXCEL sheet. And it will be needed a new method to make simple MES construction for more efficient production scheduling. This paper proposes the method which can build simple MES easily using a tool of EXCEL VBA for a small-to-medium-sized factory, and introduces an applied case by the proposed method and EXCEL VBA.