• Journal of the Korean Magnetic Resonance Society
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• v.11 no.1
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• pp.1-9
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• 2007

An unequal site exchanging system induced by restricted rotation of 9-methyl group in 1,8-dichloro-9-triptycene has been studied by spin-lattice relaxation and 2D-EXSY experiments. The exchange rate obtained from relaxation studies is very well coincident to the result of line shape analysis, and the difference of the relaxation times ($T_1$) in two different sites has an important role to analyze 2D-EXSY experimental data.

• Journal of the Korean Chemical Society
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• v.68 no.2
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• pp.74-81
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• 2024

A sulfonic acid-water-silanol system in SO₃H-functionalized MCM-41 was investigated using solid-state nuclear magnetic resonance techniques. The proton exchange rate between a water molecule and a silanol group in the S-PE-MCM-41 was determined by analyzing the 1D proton spectra, the proton EXSY spectrum, and ²H spin-lattice relaxation data under various hydration levels. Two kinds of water-bounding sites were found in the S-PE-MCM-41: weakly and strongly bound sites. Over several hours, water molecules bound to the weakly bound sites at the low hydration level migrated to the strongly bound sites. At high temperature, the S-PE-MCM-41 easily lost water molecules weakly bound to the silanol, while the strongly bound water molecules survived. Water molecules that participated in the hydration of the phenethyl sulfonate were involved in the hydrogenbonded silanol mechanism of proton conductivity. This phenomenon contributes higher proton conductivity to the S-PE-MCM-41 by the cooperation of sulfonyl and silanol groups in the proton transfer process, even at higher temperature.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1994.04a
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• pp.660-666
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• 1994

현장에서 크레인에 대한 전문적인 지식을 얻는데는 많은 시간과 노력이 소요되고 있으며 전문가의 숫자가 한정되어 있어서 고장 발생시 전문가를 부르는데 시간이 많이 소요된다. 이 문제를 해결하기 위하여 깊은 전문지식 없이 크레인의 고장을 신속히 진단하고 조치방안을 제시하는 전문가 시스템을 개발하였다. 개발범위는 가장 빈번히 고장이 발생하는 전기 부문중 전동기와 브레이크로 범위르 국한시켰다. 우선 크레인의 전기 부문에서 일어나는 고장 원인과 증상을 분석하고, EXSYS라는 전문가 시스템 Shell을 사용해 Rule을 개발하였다. 또한 각 증상에 따른 조치방법을 작업자에게 가르쳐 주기 위하여 FoxPro를 사용하여 Instruction Data Base를 개발하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.2
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• pp.51-56
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• 2003

Traditional travel information systems provide us with comprehensive information and internet-based travel information systems (IBTIS) with useful information. However, they suffer from limited access to the system, and a lack of flexibility for user requirements. In order to overcome these problems, this research introduces a knowledge-based expert system approach. As a case study, a Knowledge-based Expert System for guiding a New Zealand tour (KEGUNZ) has been developed to suggest highly user-oriented travel plans efficiently in New Zealand. KEGUNZ has been implemented using EXSYS, an expert system shell.