• Proceedings of the KIEE Conference
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• 2000.07c
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• pp.2038-2040
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• 2000

The main objective of this paper is to design and test a new type of polymer ZnO surge arrester for AC power system of railroad vehicles. Metal oxide surge arrester for most electric power system applications, electric train and subway are now being used extensively to protect overvoltage due to lightning. Surge arresters with porcelain housing must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit current. When breakdown of ZnO elements in a surge arrester occurs due to flashover, fault short current flows through the arrestor and internal pressure of the arrester rises. The pressure rise can usually be limited by fitting a pressure relief diaphragm and transferring the arc from the inside to the outside of the housing. However, there is possibility of porcelain fragmentation caused by the thermal shock, pressure rise. etc. Non-fragmenting of the housing is the most desired way to prevent damage to other equipment. The pressure change which is occurred by flashover become discharge energy. This discharge energy raises to damage arrester housing and arrester housing is dispersed as small fragment. Therefore, the pressure relief design is requested to obstruct housing dispersion. The main research works are focused on the structure design by finite element method, pressure relief of module, and studies of performance of surge arrester for electric railway vehicle.

• Journal of the Korea Institute of Building Construction
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• v.4 no.4
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• pp.117-126
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• 2004

Construction industry is faced with the problems such as the quickly changeable circumstance and increasing construction companies due to regulation mollification of company registration. In order to overcome these problems, new estimation system based on historical estimation cost is ready to introduce by government step by step. But the time of transition for estimation system causes another problems such as chaos addition to simultaneity of a standard of estimation system and new estimation system, lack of related regulation, accumulation of historical extensive cost data, and adjustment methodology when historical estimation data is applied to next projects. The purpose of this study is to suggest the change factors by activities for estimating historical cost for apartment housing projects. New estimation system is based on historical construction data. For application of this system, the standard adjustment methodology system is necessary. and extensive cost data should be accumulated under an unified construction work classification system. Therefore in this study, according to the construction work classification system, every apartment housing project was classified to 16 work classifications, and 7 major composed items which occupy more than 85% of construction costs are analyzed by detailed activities and by average ratio and maximum ratio each of them. In the result of the study, furniture work, foundation work and masonry work are the works which have big gap of costs between average ration and maximum ratio. In addition to suggestion of change factor by work species, 5 qualified construction specialists are interviewed and change factors in 7 major works are analyzed.

• The Journal of Sustainable Design and Educational Environment Research
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• v.16 no.2
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• pp.1-9
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• 2017

Defect dispute in apartment building has become a debating social issue. The system of defect lawsuit and the conciliation process are applicable to solve defect problems in South Korea. Among various defects, painting work defect is a critical issue because it requires large area works and entails a lot of cost. Accordingly, disputes on work procedure and cost calculation are argued oftenly between residents and housing providers. This study reviewed detailed main issues of painting work and propose relevant systems and standards. In this analysis, the main issues are categorized into pre-works, main work, and others. The most recent cases are compared and analyzed for each issue. After the analysis, following conclusions are obtained, (1) In defect lawsuit system, even though surface treatment work in pre-work step is part of main work, it has been separated and regarded as a separate work. (2) Although the main painting work are not significantly different from two systems, it is still necessary to achieve a consensus to close the gap in the methodology of painting area calculation and determining whole painting or partial painting. (3) In addition, unlike the profit rate of general construction works, that of painting work remained the maximum rate and additional charge rate for works carried out in higher place are different among cases. Therefore, it is determined that establishing consistent standards is urgent.

• Journal of the Economic Geographical Society of Korea
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• v.22 no.4
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• pp.592-609
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• 2019

This study attempts to expand the leverage cycle theory using the subprime real estate investors. The leverage cycle theory has demonstrated asset price fluctuations irrelevant to changes in fundamentals through the restructuring of transaction composition centered on optimistic buyers. However, it needs to understand how this theory works in the depressed housing market with low-income residential regions to explain the geographic origins of the financial crisis. In the depressed housing market, the subprime real estate investors focused on low-income residential regions. Through this spatial focus, the low-income residential regions solely have real estate investor-oriented composition of new purchase transactions in the depressed housing market. The discovery of the subprime real estate investors as new actors lays the foundation for applying the leverage cycle theory to the depressed housing market which has been a underserved area for capital investment. This attempt illustrates how the geographical reinterpretation of an economic theory reestablishes spatio-temporal context of economic phenomena.

• Journal of the Korean housing association
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• v.25 no.3
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• pp.45-52
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• 2014

Adolf Loos and Hiroshi Hara are very well known for their distinctive method of spatial composition. Adolf Loos showed white silent outer facades from his strong aversion to the ornament, whereas dynamic and rich inner space by the principle called 'Raumplan' in his housing design. Hiroshi Hara, one of the most influential architects in modern Japanese architectural history, designed a series of controversial houses with radical design by his 'Yukotai Theory' and the thought of 'Reflection House'. Even they have no common in regional background or the period of their works, both similarly have shown their own focus on cladding surface as an important design language. From this point of view, this paper investigates the design method of those two architects focused on the similar points and also the differences of their approaches to cladding in housing design. In conclusion, in case of Adolf Loos, the cladding is a tool to create completely safe and pure inner space by separating from the outside. On the other hand, the cladding of Hiroshi Hara has the meaning of social ideology that individuals must follow the principles of a dominant structure, which is the reason why the cladding should be removed. However there exists something in common also. They radically denied the outer circumstances and had a firm belief that the requests from the inside living space were the more influential factors.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05a
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• pp.74-77
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• 2000

The main objective of this paper is to design and test a new type of polymer ZnO surge arrester for AC power system of railroad vehicles. Metal oxide surge arrester for most electric power system applications, electric train and must not have explosive breakage of the housing to minimize damage to other equipment when subjected to internal high short circuit current. When breakdown of ZnO elements in a surge arrester occurs due to flashover, fault short current flows through the arrester and internal pressure of the arrester rises. The pressure rise can usually be limited by fitting a pressure relief diaphragm and transferring the arc from the inside to the outside of the housing. However, there is possibility of porcelain fragmentation caused by the thermal shock. pressure rise, etc. Non-fragmenting of the housing is the most desired way to prevent damage to other equipment. The pressure change which is occurred by flashover become discharge energy. This discharge energy raises to damage arrester housing and arrester housing is dispersed as small fragment. Therefore, the pressure relief design is requested to obstruct housing dispersion. The main research works are focused on the structure design by finite element method, pressure relief of module, and studies of performance of surge arrester for electric railway vehicle.

• Explosives and Blasting
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• v.20 no.3
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• pp.83-96
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• 2002

Reconstruction and redevelopment of old and dilapidated apartment and housing have been increasing to provide more housing accommodation and to secure the safety of building structures since the middle of 1990's. Since, however, little researches on the demolition technique have been made, conventional mechanical demolition method were applied to the most of works that resulted in flooding in small demolition companies. Problems associated with mechanical demolition method are increase not only in working days and costs, but also in public claims, particularly for high-rise building structures. This is to contribute the demolition industries bt providing the concept, standards, and technique of demolition engineering while maximizing working efficiency and minimizing public claims.

• Journal of the Korean housing association
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• v.16 no.3
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• pp.69-77
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• 2005

The purpose of this study is to develop a automation for decision of the optimum stories in apartment buildings in order to assure the solar access right for neighboring areas. Compared to the results of the optimum stories by manual process through applying a legal case over solar access right, the proposed method provides more improved and expanded information by automating the computing process of decision of the optimum stories in apartment buildings. With the result of this research, it would be possible to furnish with advanced information for an amicable settlement against the civil petition and disputes, to reduce waste of the time and cost and to improve the efficiency of solar access right analysis works.

• Journal of the Korean housing association
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• v.11 no.2
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• pp.63-73
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• 2000

The purpose of this study was to find a suitable standard height of the lavatory in public spaces through the review of relevant regulations, questionnaire survey, lab works, and experiment to measure lavatory heights. The results of the study were as follows: First, the heights of the current public lavatory were ranged from 68cm to 89cm, and the heights to the faucet were from 71cm to 91cm. The recent lavatory was more likely to be higher in heights. Secondly, the suitable height for public lavatory was ranged from 55% to 65% of the heights of the participants put on shoes. Thirdly, 90cm lavatory in height was considered to be more suitable to use for the majority than was 83cm lavatory. Fourth, the author suggest that the suitable y(lavatory height)=77.818 + 0.117x(put on shoes heights). This study suggested that adopting 95% range, the most suitable height of public lavatory is more than 90cm high for the people whose heights are more than 150cm.

• Journal of the Korean housing association
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• v.7 no.2
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• pp.153-160
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• 1996

The purpose of this study was to examine the tendency of demands and satisfaction according to the resident's characteristics using the Cognitive Measurement Scale of Residential Life Management. Data were analyzed by the SAS program package. The results of study showed that the degree of satisfaction in the life management was low. And highest demand of each factor was as follows : Life cooperative association in Fesidential life convenience service(I). Bank service in Residential life support service(II). Announcement about utility fee in Resident's activity support and announcement of managerial warks(III). Works about criminiality control in Safety and order sustaining(IV). Care for empty house in Precaution to accident(V).