• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.6
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• pp.870-875
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• 2013

After introducing diagnosis equipment power failure prevention activities for distribution system have become more active. To do facility diagnosis and maintenance work more efficiently we need to evaluate reliability for the system and should determine the priority line with appropriate criteria. Thus, to calculate risk factor for the power distribution line that are composed of many component facilities its historical failure events for the last 5 years are collected and analysed. The failure statics show that more than 60% of various failures are related to environment factors randomly and about 20% of the failures are refer to the aging. As a strategic evaluation system reflecting these environmental influence is needed, a system on the basis of the probabilistic approach related statical variables in terms of failure rate and failure probability of electrical components is proposed. The figures for the evaluation are derived from the field failure DB. With adopting Bayesian rule we can calculate easily about conditional probability query. The proposed evaluation system is demonstrated with model system and the calculated indices representing the properties of the model line are discussed.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.4
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• pp.177-184
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• 2005

This paper proposes a improved investment priority decision method of the facilities considering the reliability of distribution networks. The proposed method decides a investment order of the facilities combining, by fuzzy rules, the investment priority decision of KEPCO and the priority decision considering reliability evaluation indices. Where reliability evaluation indices are SAIFI(System Average Interruption Frequency Index) and SAIDI(System Average Interruption Duration Index), as referred to evaluation index for sustained interruption. The reliability analysis method of distribution networks applied in this paper utilizes analytic method, where the used reliability data is historical data of KEPCO. Particularly, we assumed that the failure rate increased as the equipment ages. To verify the performance of the proposed method, we applied it with the planned projects to reinforce the weak facility electrical facilities in KEPCO in 2004. The evaluation result showed that, under a limited budget, the reliability of the KEPCO in the Busan region using the proposed method can be enhanced than using the conventional KEPCO's method. Therefore, the results verify the proposed method can be efficiently used in the actual priorities method for investing the electrical facilities.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.24 no.1
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• pp.15-24
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• 2021

This study was carried out to propose the functional assessment and a wise use strategy on the ecologically valuable 'village wetlands' distributed in living area in Geumsan gun, Chungnam province, Korea. The targets of the functional evaluation were 24 wetlands, selected from 123 village wetlands, where villages and agricultural lands or core ecosystems are located within living area near the wetland and wetlands with historical and cultural significance. The functional evaluation was carried out by RAM (Rapid Assessment Model) and the conservation strategies were suggested. As a result of the functional evaluation, 9 wetlands were rated 'high' (2 'absolute conservation' and 7 'conservation' strategies), 14 wetlands were rated 'medium' ('enhancement' strategies), and one wetland was rated 'low' ('restore or enhancement' strategy). In consideration of the results of the functional evaluation, interviews with village residents, and historic meaning, 6 important village wetlands were selected that require additional management strategies, such as conservation, enhancement, and restoration. 2 wetlands were from "absolute conservation" strategy and 4 wetlands derived from "conservation" and "enhancement" strategy wetlands in consideration of the ecological connectivity of wetlands, the use of surrounding land, and the function as a biological habitat. The wise use and conservation strategy was specifically proposed respectively.

• Journal of the Korean Society for Railway
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• v.12 no.6
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• pp.921-926
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• 2009

The RPN provides information which includes the risk level and the priority order of maintenance tasks for components. However, if there is no sufficient historical failure data, the historical failure data from other sources can be applied to the target system. And if we use historical data from other sources without any process, there will be concomitant problems according to a discord of each system characteristic, a difference between the present and the date of failure data, etc. In this paper, a new methodology is proposed to model the failure rate as a fuzzy function to resolve these problems. Taking advantage of this result, the RPN can be calculated by using the fuzzy operation. The proposed method is applied to the substation system.

• Journal of the Korea Society of Computer and Information
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• v.7 no.4
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• pp.94-101
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• 2002

It expected a lot of changes in mass media and documentation expression as documents on web are getting diverse, complex and massive. An Annals of The Chosun Dynasty is a very important document used for researching historical facts and is published as CD-Rom. However. The CD-Rom was composed as content-based and using simple search method, therefore it's very difficult to make determine event-relationship between documents factors. Because of that, we studied to discover event-relationship between documents through clustering and efficient similarity method among Annals of The Chosun Dynasty. For the research method, we discovered the best similarity method for historical written documents through simulation similarity measures of Annals of The Chosun Dynasty documents. Then we did simulation-clustering documents based on similarity probability. In evaluation of the clustered documents , the results were the same as when manually figured.

• Journal of Korea Water Resources Association
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• v.46 no.3
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• pp.287-299
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• 2013

The objective of this study is to derive and evaluate the drought threshold level based on hydro-meteorological data using historical drought events. After collecting the drought events during 1991 to 2009 year, the observed meteorological data and estimated hydrological component from LSM are used as input for the percentile analysis that is drought analysis data. The drought threshold level that precipitation and runoff of 3 month duration are less than 35%, soil moisture of 2 month duration is less than 35% and evapotranspiration of 3 month duration is more than 65% is derived using ROC analysis that are objective test method. ROC analysis with SPI (3) is performed to evaluate the applicability of threshold level in the domestic. As a result, it can be concluded that the derived drought threshold level show better performance to reflect the historical drought events than SPI (3) and it reasonably explain the spatial drought situation through the spatial analysis.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.10 no.2
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• pp.73-81
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• 1992

Terrestrial photogrammetry is widely used for the observation of cultural assets due to its effects such as increased accuracy and cost saving. As the damage of cultural assets tends to increase with time, it is essential that the standard of value evaluation and the preservation methods be established. The terrestrial photogrammetry proves to be an excellent tool for this purpose. This study aims to classify the objects measured by terrestrial photogrammetry according to the historical period. The assets to be included are not only national treasures but also obscure cultural assets. This study also aims to discover the genuine value and originality of the asset by analysis of formative ratio. As the result of this study, it is proved that the stone pagodas bave been build by characteristic formative ratio, which varies according historical period. It is anticipated that the results of this study will be applied in deriving the historical periods of discovered stone pagodas as well as in preserving existing cultural assets.

• Journal of Korean Society of Rural Planning
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• v.16 no.4
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• pp.117-129
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• 2010

This study is to make value estimating system to valuate prototype landscape of rural and to derive itemized importance to select priority preservable object The results of the study are summarized as follows, It is examined value estimating standard by analyzing prototype landscape related previous study, law and order. Also, It is derived conclusive prototype landscape value estimating system by doing attribute assessment of preserving objects while surveying the site and interviewing professionals, Value estimating system is classified into five items of physical value which are integration, harmony, diversity, symbolism and aesthetics, The historical-cultural value are divided into four categories which are religious value, originality, historicity and scarcity, The communal values are divided into three categories which are sociality, continuing and regional locality and also divided into three categories which are rarity, primitiveness and diversity as the ecological value, Relative priority of prototype landscape value estimating system result is derived as historical-cultural value as the superior position and physical value, communal value and ecological value as the priority order. In the subordinate, historical categories are derived to be the most valuable and originality, symbolism, integration, regional locality, continuing, harmony, aesthetics, religious value, primitiveness, diversity of physical values and diversity of ecological value in order of the priority assessment The results of the study have the meaning of practical use in prior selection and preservation plan of preserving prototype landscape as practical alternative plan for systematical preservation of damaging prototype landscape.

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2005.06a
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• pp.221-230
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• 2005

To support the design concept and performance evaluation of the cover system for low- and intermediate-level radioactive waste(LILW) disposal facility, the pioneering study is conducted with the tomb of historical age. Research status of the art are followed and the characteristics of tomb cover are summarized based on the preservation of historical remains. Visiting the excavation site of historical tomb and communication with Korean archeological society is required for the further understanding and for the extension of radioactive waste disposal research.

• Journal of architectural history
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• v.17 no.6
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• pp.67-86
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• 2008

Main theme of this paper is the evaluation of the historical significance of Luciano Baldessari's exhibition works mainly during the Fifties. In order to understand the formal and logical basis of those project, his relationship with the historical Avant-gardes and the consequences expressed in his pavilion projects for the Breda Industrial Company are analyzed. The first part focuses on the influence of Italian Futurism, German Expressionism and Italian Rationalism on the formation and experience of Baldessari during the interwar years. The encounter with these movements determine the interest but also the principles along which Baldessari represents his idea of object, space and place. Specially his professional activities during Fascism would determine his attitude toward political power and the necessity of autonomy in artistic sphere. In the second part, different themes that Baldessari affronted in each project of Breda Pavilions is analyzed. Another important issue regard the historiography of the contemporary architecture. Often, many important works that lies in the threshold of the disciplines such as painting and sculpture and media art were excluded in the history of architecture just because they do not deal with the architectural object. Recently, many elements such as theatrical project and temporary objects are considered as part of urban reality and architecture with acknowledgment of their capacity to create event and situations. Along this thought, not just the reconfiguration on the territory of architecture in present but also the criterion to evaluate the past history of architecture is changing drastically. This study on the pavilions of Baldessari intends to contribute indirectly on the current issue of dominion of architecture, but also to evaluate objectively recent architecture. Consequently, architectural protagonists such as Baldessari and their ephemeral projects would be evaluated compressively in their multiplicity of significance.