• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2197-2199
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• 2003

Most of distributed PLC system is secured reliability of the system by fully duplicated controller. But it costs too much. In this paper, we proposed fault tolerant control using minimum spare controllers. First, the system is modeled using Galois field. Next, we designed additional spare controllers using the parity code of two dimensions. Finally, the algorithm for producing estimated output in remote I/O when the fault occurs was suggested. This method will be applied to an automatic system in order to increase reliability and improve cost performance.

• Bulletin of the Korean Chemical Society
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• v.17 no.2
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• pp.128-131
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• 1996

From Raman spectra, the ${\nu}g$C=O frequencies of 4-substituted benzaldehydes were found to correlate with the ${\sigma}_p$ values of the 4-x atom or group as well as the acceptor number (AN) values of solvents. In various solvents, the ${\nu}g$C=O frequency of benzaldehyde decreased upon the increase of benzaldehyde concentration. This shift was mainly due to the hydrogen bonding between the carbonyl oxygen and/or aldehydic proton of benzaldehyde and the solvent molecules. Over the 1-80 volume % change, the ${\nu}g$C=O frequency of benzaldehyde down shifted from 1709.4 $cm^{-1}$ to 1700.2 $cm^{-1}$ in CCl4 solution and from 1703.0 $cm^{-1}$ to 1698.0 $cm^{-1}$ in $C_2H_5OH$ solution. This is due to the fact that hydrogen bonding between the benzaldehyde and C2H5OH was much stronger than that between the benzaldehyde and the other solvents.

• Bulletin of the Korean Chemical Society
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• v.22 no.9
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• pp.989-993
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• 2001

The carbonyl stretching vibration, νC=O of 2-cyclohexene-1-one, is in Fermi resonance with a combination tone. The amount of Fermi resonance interaction between these two modes is dependent upon the amount of solute/solvent interaction due to hyd rogen bonding between the carbonyl oxygen and the solvent proton. The corrected νC=O frequency of 2-cyclohexene-1-one occurs at a lower frequency than the observed νC=O mode of cyclohexanone, possibly caused by expanded conjugation effects. The carbonyl stretching modes of cyclic ketones were also affected by interaction with the ROH/CCl4 mixed solvent system.

• Proceedings of the Korean Society for Information Management Conference
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• 2013.08a
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• pp.75-82
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• 2013

리포지터리는 학술정보 유통의 새로운 패러다임이자 연구자간의 연구성과물에 대한 개방과 공유를 지원하는 중요한 기반 기술이다. 북미나 유럽지역을 중심으로 구축되기 시작한 리포지터리는 2005년 이후 동아시아 지역에도 점차 확산되고 있으며 이러한 추세는 향후에 더욱 확산될 것으로 기대된다. 본 연구에서는 한국, 중국, 일본을 포함한 동아시아 지역의 국가별 리포지터리 확산과 질적 성장을 5년간에 걸쳐 연대기적으로 분석해보고 성장의 배경이 되는 국가별 리포지터리 정책의 개요를 간략하게 살펴보고자 한다. 문화적 유사성과 지역적으로 근접한 국가들의 현황을 살펴보는 것은 우리나라의 보다나은 리포지터리 확산 정책 수립을 위한 기초적인 정보를 제공할 수 있을 것이다.

• Proceedings of the Korean Society for Information Management Conference
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• 2013.08a
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• pp.93-100
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• 2013

빠르게 진화하는 웹 검색엔진 및 기술은 도서관의 기존 OPAC 시스템에 대한 반성과 변화에 대한 요구를 가져왔다. 이렇게 등장한 '차세대 OPAC'의 개념을 사용하여 본 연구에서는 차세대 OPAC의 특징적인 기능 27개로 구성된 체크리스트를 개발하였고 우리나라 대학도서관의 차세대 OPAC 수용 정도를 파악하기 위한 도구로 사용하였다. 조사대상은 우리나라 4년제 일반대학교 도서관 191개관의 OPAC이었다. 본 논문에서는 우리나라 대학도서관별 차세대 OPAC의 수용 정도를 파악하고 이러한 혁신기술의 수용 요인을 모기관의 조직적 그리고 외부 요인 측면에서 살펴보고자 하였다. 기능 자체에 대한 요인 분석은 본 연구에서 제외되었다.

• Journal of Urban Science
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• v.11 no.1
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• pp.59-68
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• 2022

This study, the meaning of historical and cultural content utilization in urban regeneration was examined and in the process, the causal relationship between each variable was verified through path analysis among physical, cultural, social, and economic factors. The purpose of this study is to find the main variables of historical and cultural content urban regeneration projects in which the moderating effect of economic factors and demographic characteristics, which are mediating effects, have a significant effect on resident participation and life satisfaction of local residents. Furthermore, by presenting a more integrated and effective urban regeneration policy plan, it is intended to ultimately contribute to the vitalization and direction of urban regeneration.

• Journal of the Korean Society for Library and Information Science
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• v.31 no.1
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• pp.153-184
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• 1997

The importance of WWW search services is increasing as Internet information resources explode. An evaluation of current 9 search services was first conducted by comparing descriptively the features concerning indexing, searching, and ranking of search results. Secondly, a couple of search queries were used to evaluate search performance of those services by the measures of retrieval effectiveness. the degree of overlap in searching sites, and the degree of similarity between services. In this experiment, Alta Vista, HotBot and Open Text Index showed better results for the retrieval effectiveness. The level of similarity among the 9 search services was extremely low.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.4
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• pp.477-483
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• 2007

A coagulation process for RO (reverse osmosis) membrane pretreatment system was an effective technology to remove colloidal and particulate matters. However, coagulant residuals from the pretreatment process may negatively affect RO membrane performance. The bench-scale coagulant exposure study was performed to investigate the effect of their residual on adsorbed mass which related to the membrane performance. Coagulant addition in this study ranged from 0 to 5mg/L ferric chloride, alum, and 2mg/L cationic polymer(poly-di-methyldiallyl ammonium chloride) as coagulant aids. This results showed that adsorbed mass is not significantly increased during short-time period, however, accumulated mass of coagulants on the membrane surface is significantly increased during long-time experimental period. The effect of pH on coagulants adsorption characteristics was significantly differed due to the electrostatic repulsive interactions between soluble coagulants and membrane surface charge. This data suggest that the RO membrane performance of drinking water treatment plant could be decreased by adsorption of residual coagulants when applied for the coagulant pretreatment process.

• Journal of the Korean Society for information Management
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• v.19 no.1
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• pp.135-161
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• 2002

This study presents a multilingual integrated ontological approach that enables linking classification systems. thesauri. and terminology databases in science and technology for more effective indexing and information retrieval online. In this integrated system, we designed a thesaurus model with concept as a unit and designated essential data elements for a terminology database on the basis of ISO 12620 standard. The classification system for science and technology adopted in this study provides subject access channels from other existing classification systems through its mapping table. A prototype system was implemented with the field of nuclear energy as an application area.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.4
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• pp.187-194
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• 2015

This paper describes the PI controller design based on a practical transfer function model for centrifugal water chillers. The rotational speed of a compressor and the opening angle of an electronic expansion valve were simultaneously regulated as manipulated variables to maintain temperature reference and to ensure high efficiency of the chiller. The COP according to the change in each variable was investigated by performing some static experiments, and it was reflected in the PI controller design to accomplish the high efficiency control. Especially, the practical transfer function model of the chiller was built based on the dynamic experimental data considering the strong inherent non-linearity and complexity of the chiller system. The validity of the designed PI controller was proven by some experimental results using the test facility and the results were also compared to the conventional evaporating pressure control results.