• Journal of the Korean Ceramic Society
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• v.20 no.2
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• pp.93-98
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• 1983

The sensitivity characteristics of $SnO_2$-based gas sensor prepared by sintering method have been studied at the presence of CO and Propane gas. Samples mixed with 1wt% $La_2O_3$ and 1wt% $PdCl_2$ showed highest sensitivity to CO and propane gas at 250$^{\circ}$C but the addition of $CeO_2$ did not enhance the sensitivity. For slectivity for gas a $SnO_2-La_2O_3$ (1wt%) sample without $PdCl_2$ showed better results. A sample sintered sintered at 115$0^{\circ}C$ has shown the optimum condition in sensitivity and electroding

• Journal of the Korean Ceramic Society
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• v.12 no.1
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• pp.5-11
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• 1975

Thick film resistor paste was made utilizing oxide materials such as SnO, SnO＋Sb2O3, and SnO＋Zn. The oxide materials were mixed respectively with Q-12 glass powder and finally suspended in ethyl cellulose dissolved in ethyl cellosolve. Thick film resistor was made by screen printing the paste on the alumina substrate and firing it at a suitable temperature. Among thick films made from the resistor paste, the thick film containing 85% SnO and fired at $600^{\circ}C$ demonstrated the finest electrical properties showing 10 K ohm in sheet resistance, 110 ppm/$^{\circ}C$ in TCR. In general, TCR of the thick films made from the oxide-mixture paste is good in linearity, therefore it is suggested the oxide-mixture paste is utilized as the negative thermistor.

• Journal of the Korean Ceramic Society
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• v.27 no.6
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• pp.741-746
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• 1990

Dielectrics which do not lose their high insulation resistance in reducing atmosphere are necessary for multilayer ceramic capacitors with Ni internal electrode. In this study we investigated the Ca ion site occupancy in A-site excess Ca-doped BaTiO3 by measuring the insulation resistance, lattice constant and Curie temperature. Its Curie temperature, which was lower than that of the pure BaTiO3, was more lowered by sintering in reducing atmosphere. Lattice constnat of c-axis decreased and that of a-axis increased, suggesting substitution of Ca ions for Ti ions. Hence CaTi" acts as an acceptor to maintain high insulation resistance.ance.

• Journal of the Korean Ceramic Society
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• v.27 no.5
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• pp.638-644
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• 1990

The C3H8 gas sensitivities of SnO2, Pd-SnO2, Pt-SnO2 gas sensor are looked over with the impregnation method of PdCl2, H2PtCl6 solution on SnO2. The Cl- ion due to incomplete decomposition of PdCl2 at 80$0^{\circ}C$ for 30 min decrease the C3H8 gas sensitivity of SnO2, and the sensitivity is increased by the impreganation of H2PtCl6 solution on SnO2 because of its lower decomposition temperature compared with PdCl2. The C3H8 gas sensitivities of Pd-SnO2, Pt-SnO2 impregnated slightly after 1st sintering are larger than that of pure SnO2 sensor because very small amount of Cl- ion exist in sample due to smaller amount of impregnaiton.

• Journal of the Korean Ceramic Society
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• v.17 no.1
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• pp.13-19
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• 1980

Mineral identifications on halloysite in Hadong-Sancheong area and the halloysite bearing clay ii Yeoju, Yesan and Hampyeong-Muan area are carried out by the method of X-ray diffraction, electron microscopy and DTA. Chemical composition of the above minerals are analyzed by means of X-ray-fluorescence. Refractoriness are also measured by refractoriness tester. A standard diagram for quantitative analysis of halloysite is given.

• Proceedings of the Korean Information Science Society Conference
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• 2003.10a
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• pp.784-786
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• 2003

패스워드 기반 키 교환 프로토콜은 참여자들이 쉽게 기억할 수 있는 자신의 패스워드를 사용하므로 단순성, 편리성, 이동성의 장점 때문에 광범위하게 사용된다. 2000년에 Lin, Sun, Hwang［1］이 Steiner, Tsudik, Waidner［2］가 제안한 three-party EKE 프로토콜(STW-3PEKE)이 패스워드 추측 공격에 취약함을 증명하고 이를 개선한 서버의 공개키를 이용한 새로운 three-party EKE 프로토콜(LSH-3PEKE)을 제안했다. 2001년에는 Lin, Sun, Steiner, Hwang［3］이 서버의 공개키를 사용하지 않는 새로운 three-party EKE 프로토콜(LSSH-3PEKE)을 제안했다. 본 논문에서는 검증자(verifier) 기반 즉 서버가 사용자의 패스워드를 저장하지 않고 패스워드에 의해 생성되는 검증자를 가지는 프로토콜을 제안하며 이전에 제안한 프로토콜의 안전성을 그대로 유지하면서 좀 더 간단하며 효율적인 프로토콜을 제시한다.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.4
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• pp.394-401
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• 1991

B-spline function is generally used for an image interpolation because of its smoothness and continuity, but it accompanies a large amount of blurring effect. In this paper, a space-variant B-spline interpolation function is proposed through deblurring process followed by de-aliasing process. The proposed function has parametric expression and performs smoothing and edge-enhancement adaptively in the interpolation process according to local property of the image. Application of this function to image enlargement, rotation, and curve representation producted good results. Even in the presence of noise, noise smoothing effect as well as edge-enhancement were observed in the image interpolation process.

• Proceedings of the Korea Information Processing Society Conference
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• 2001.10a
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• pp.139-142
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• 2001

VRML(Virtual Reality Modeling Language)에서 객체를 구성하는 자는 VRML 노드들 사이에 놓인 이벤트들의 루트를 밝힘으로써 가상 세계에서 동적으로 상태가 변화하는 것을 허용한다. 그런데 VRML에 정의된 개념적인 실행 모델에서 이벤트는 즉각적으로 노드들의 예정지로 전달되어야만 한다. 그러나 다양한 분야에서 동시에 일어나는 이벤트나 노드들 사이에서의 주기적 의존성과 같은 복잡한 요구를 수반하는 노드들 사이의 관계에서는 브라우저 실행을 어렵게 하는 문제가 있다. 따라서 본 논문에서는 VRML 부라우저에서 이벤트를 처리하는 기법과 복잡한 형태 루트들에 대한 이벤트 처리 방법을 제시하고 시뮬레이션을 통해 타당성을 검증한다.

• Journal of Korean Physical Therapy Science
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• v.4 no.1
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• pp.291-301
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• 1997

This study was conducted to fine out factors related with the complains low back pain in eldery persons. The Questionnaires was done for 273 eldery persons who live in Pusan, Anyang, Ansan region from May 1996 ro April 1997. The results were as follows : 1. The prevalence rate were 49.5% and among them 20.74% were male was while 68.12% which shows high prevalance of female 2. There were no statistical significance except sex difference(P>0.05) 3. There statistical different with some factor fators which includes general health condition, the frequency of treatment, sleeping bed style, condition for future life (P<0.05). But showed no statistical significance with the other factors. 4. When compared between rural and urban area, there were some statistical difference among some factor such as ; where to treat, moring exercise frequency, walking duration, sleeping bed style, agricultural work involement, prepartory condition for future life.(P<0.05)

• Journal of KIISE:Software and Applications
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• v.28 no.5
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• pp.431-439
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• 2001

최근 본격적으로 서비스되기 시작한 비교쇼핑몰들은 번거로운 쇼핑과정을 대신하여 한 사이트 내에서 원하는 상품에 대한 통합검색과 비교가 한번에 이루어지게 해준다. 그러나 에이전트에 의해 수집된 상품정보의 양이 방대해진 반면 고객중심의 one-to-one marketing이 이루어지지 않아 불필요한 정보로 인해 여전히 쇼핑의 효율이 낮다. 본 논문에서는 등록된 각 고객의 프로파일과 관심도에 따라 코드화된 정보의 처리를 통하여 개별적인 상품정보의 제공과 한 번의 클릭으로 원하는 쇼핑몰의 원하는 상품만을 비교해 보여줄 수 있는 멀티 에이전트 기반의 개인화된 비교쇼핑 시스템을 제안한다. 또한 학습된 고객의 관심도와 프로파일을 이용하여 구매가 예측되는 상품을 적절한 시간에 e-mail 푸쉬 서비스로 추천 및 광고하여 추가 쇼핑으로 이어질 수 있게 하였다.