• Journal of Energy Engineering
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• v.18 no.1
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• pp.1-8
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• 2009

This paper reports the experimental study of natural convection heat transfer with $Al_2O_3$-water nanofluid. Experimental apparatus was a cylindrical enclosure with adjustable fluid layer thickness, and the aspect ratio was varied between 10.9 and 30.4. Heat transfer coefficients seemed to have reached a steady value within 30 minutes as the case with pure water. But, decrease in heat transfer coefficient continued for over $1{\sim}2$ hours for inclination angle of $0^{\circ}$, and oscillation in heat transfer was observed for certain inclination angles and aspect ratios for over 10 hours. Oscillation shape and period depended on the aspect ratio and inclination angle. For example, the oscillation period for $0^{\circ}$ was more than twice that for $60^{\circ}$. The maximum Nusselt number occurred at the inclination angle of $30^{\circ}$, and the minimum occurred at $60^{\circ}$ for Rayleigh number less than 1.E5. However the present results were obtained with aggregated nanofluid and would be devoid of generalities.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.3
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• pp.283-290
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• 2016

Recent, the construction of the multi-purpose double-deck tunnel is required to solve the flood protection and congested area at urban city. The multi-purpose double-deck tunnel is desperately needed for the introduction of efficient utilization of underground space in addition to the main feature of road capabilities. A basic review was performed for site selection to consider the control capability and features of road tunnel at the same time, and the processable flow in accordance with tunnels cross section of double deck tunnel. Site Selection Criteria for multi-purpose use of the double-deck tunnel has been proposed through the site selection criteria by use of the tunnels review. Also the estimation processable flow was performed to review the versatility of double-deck tunnel due to design of tunnel cross-section. Site Selection of double-deck tunnel from this study can be seen the need for a complex consideration through a variety of analyzes.

• The Journal of the Korea Contents Association
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• v.16 no.2
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• pp.354-364
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• 2016

The purpose of this study is to analyze current condition and features of female development funds of Busan primary local self-government, and to make useful implications out of this so that the local female development funds can contribute to its ultimate purpose, which is to achieve female development. The analyses show that 1) local self-governmental districts with good finance try to reserve funds by reducing programs; 2) local laws, which serve as the legal basis of female development fund utilization, do not reflect the value of gender equality; 3) the programs run by the female development funds lack contents; 4) beneficiaries of the fund programs aremixed; and 5) female policies and family policies are not separated, exhibiting the limitations of feministic perspectives. I propose that 1) the fund should be raised through the governance of local female groups and self-governments; 2) basic local laws should be revised: 3) gender perspective contents and birth support policy should be implemented.

• Journal of KIISE:Software and Applications
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• v.30 no.7_8
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• pp.703-712
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• 2003

With the explosive growth n the numbers and sizes of imaging technologies, Content-Based Image Retrieval (CBIR) has been attacked the interests of researchers in the fields of digital libraries, image processing, and database systems. In general, in the case of query-by-image, in user has to select an image from database to query, even though it is not his completely desired one. However, since query-by-sketch approach draws a query shape according to the user´s desire it can provide more high-level searching interface to the user compared to the query-b-image. As a result, query-by-sketch has been widely used. In this paper, we propose a Java-based image retrieval system that consists of sketch query and image classification. We use two features such as color histogram and Haar wavelets coefficients to search similar images. Then the Leave-One-Out method is used to classify database images. The categories of classification are photo & painting, city & nature, and sub-classification of nature image. By using the sketch query and image classification, w can offer convenient image retrieval interface to user and we can also reduce the searching time.

• Journal of the Korean Institute of Landscape Architecture
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• v.30 no.6
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• pp.128-140
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• 2003

The purpose of this research was to present characteristics for the classification of biotopes and classification method of biotopes as basic data for ecological landscape planning in Metropolitan Daegu. The results of this study were as follows. 1) The study identified fifteen characteristics for classification of biotopes. Ecological landscape characteristics were divided into structural and functional factors. There are six structural factors such an inclination, and nine functional factors such as temperature. 2) The study area was separated into sixty eight biotope types. For example, an industrial district was divided into two biotope types: a biotope type of an industrial district with abundant green space, and a biotope type of an industrial district with scarce green space. 3) In the result of cluster analysis using the average linkage method between groups, biotope groups were divided into fifteen clusters and biotope groups were divided into seven clusters. Each cluster was named according to the features of a descriptive statistics analysis. For example, cluster 8 was identified as a biotope type with an impermeable pavement rate of more than 90 percent and an afforestation rate under 10 percent. 4) Fifteen biotope groups were converted to land use patterns for remote application and utilization of urban biotope in city planning. Biotope groups of a building area beyond an intermediate floor with an afforestation rate under 20-30 percent was converted to a land use pattern such as a tall apartment complex or commercial district. When examining the characteristics that were established in this research, there was a limit to achieve the objective of grade-classification because of a lack of related basic data. The research of landscape ecological characteristics for the classification of biotopes could not be completed due to a lack of time and resources, thus the study of ecological landscape characteristics will be accomplished over time.

• KIEAE Journal
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• v.13 no.6
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• pp.29-37
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• 2013

The modern town houses in Philippines has been changed through Spanish colonization over 300years and American military administration in 20C. Especially Cebu, the first contemporary capital of colonized Philippines by Spain, has various cultural characteristics and historical remains including old houses. By the economy condition in Cebu growing up, Bahay na bato, stone and wood house, has been settled for the elite or middle class of Cebu around 19C influenced by Spanish or Europe and Philippines native house called bahay kubo. Bahay na bato shows a common features, as revealed in this study, which all of them has a two stories with cut stone curtain wall and wooden beam and lintel, fronting the main street by approaching directly from street. And spatial separating also shown by setting living space to upper level instead of using storage or entrance hall called zaguan in lower level. Bahay na bato studied here shows a particular appearances in elevation, having volada and elaborate geometric or floral window pattern, also playing a role for ventilation with vetanilas below volada and main window in section. They have a rectangular plan with caida, sala, comedo, azotea almost similar to Spanish and ealier colonial Mexico style mixed with Philippines traditional style showing the strong spatial separation functionally and space wideness for party occasionally.

• Geomechanics and Engineering
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• v.7 no.6
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• pp.589-612
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• 2014

This study includes determination of liquefaction potential in Erzincan city center. Erzincan Province is situated within first-degree earthquake zone on earthquake map of Turkey. In this context, the earthquake scenarios were produced using the empirical expressions. Liquefaction potential for different earthquake magnitudes (6.0, 6.5, 7.0) were determined. Liquefaction potential was investigated using Standard Penetration Test (SPT). Liquefaction potential analyses are determined in two steps: geotechnical investigations and calculations. In the first steps, boreholes were drilled to obtain disturbed and undisturbed soil samples and SPT values were obtained. Laboratory tests were made to identify geotechnical properties of soil samples. In the second step, liquefaction potential analyses were examined using two methods, namely Seed and Idriss (1971), Iwasaki et al. (1981). The liquefaction potential broadly classified into three categories, namely non-liquefiable, marginally liquefiable and liquefiable regions. Additionally, the liquefaction potential index classified into four categories, namely non-liquefiable, low, high and very high liquefiable regions. In order to liquefaction analysis complete within a short time, MATLAB program were prepared. Following the analyses, liquefaction potential index is investigated by Iwasaki et al. (1982) methods. At the final stage of this study, liquefaction potential maps and liquefaction potential index maps of the all study area by using IDW (inverse distance weighted) interpolation method in Geostatistical Analyst Module of ArcGIS 10.0 Software were prepared for different earthquake magnitudes and different depths. The results of soil liquefaction potential were evaluated in ArcGIS to map the distributions of drillings with liquefaction potential. The maps showed that there is a spatial variability in the results obtained which made it difficult to clearly separate between regional areas of high or low potential to liquefy. However, this study indicates that the presence of ground water and sandy-silty soils increases the liquefaction potential with the seismic features of the region.

• The Journal of Society for e-Business Studies
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• v.18 no.4
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• pp.169-193
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• 2013

This study investigates time series data on internet banking systems and business performances for 5 large-scale banks : Kookmin, Woori, Hana, City, Shinhan. These banks have the common features that they merged with other banks around 2000, hence they experienced massive IS integration between banks. This study adopted VAR and VECM for identifying Granger causality between the quality of internet banking systems and the performances of banks(operating revenue and cost). The main results are as follows. First, internet banking system impacts positively on the revenues as well as costs of banks. Second, the improvement of internet banking system is instigated by cost part more than revenue part. Hence, the results imply that banks tries to reduce operating costs via internet banking systems, however the systems rather increased the costs of banks, although the systems increased operating revenues of banks too.

• Journal of the Korean housing association
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• v.25 no.2
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• pp.109-120
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• 2014

This study is focused first on considering the factors which invigorate the community in an apartment complexes from the precedent study and on identifying the specific factors, necessary to run vigorously the community in an apartment complexes. After that, the study is devoted to develop the management scenarios suitable for each type, through identifying, on the basis of the factors, the operation type of the 15 apartment complexes, in which the Seoul city community experts exist. The study result could be the basis to find out an effective method to run and manage community facilities and programs according to the features of an apartment. On the study, the 1:1 in-depth interviews were conducted on the community experts, who supported the community management in the five autonomous districts in Seoul. The study found followings. 1) The community factors needed to be readjusted in respect of operation and management. to estimate how active the community in an apartment complexes was. After identifying the community operation factors, the factors in human resources, material resources, and financial resources, were figured out. 2) The five groups were drawn from the 15 apartment complexes. The grouping was based on the relation between the main operators in each factor which invigorates the community operation. As the result, the relationship between the main operators was vertical. In addition, the more operators. 3) Six types were drawn after grouping the operation status of the 15 apartment complexes on the factors which affected to the community invigoration: human resources, material resources, and financial resources. Consequently, the managing scenarios to invigorate the community in each type were suggested.

• Journal of the Korean Institute of Rural Architecture
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• v.17 no.1
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• pp.83-94
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• 2015

The area of domestic urban design and architecture has established its original characteristics as various programs and functions were created in the drastically changing society. Such features have been presented in a certain type of patterns or unique formations, which demand a gradual development of designs in harmony with the functions and roles of the city and thus designers are forced to continue thinking deeply on this matter in their own perspectives. In particular, such demands are outstandingly high in reality in historical cities such as Andong, which this study works on. As the design contest winner is based on the geographical characteristics and locality, Confucianism and seonbi(Korean classical scholar) spirit, which are regarded as a philosophy of value, how the traditional concepts could be reflected in the plan was the focus of the discussion. The conclusions deduced from such a background include the following. First, it is necessary to make an approach on the basis of the concept in traditional architecture at the complex planning level based on the ideology in the implementation plan that requires traditionality for a complex design with contemporary functions. Second, it is important to approach this as an exploration of a solution to globalize Confucian culture in the future based on the cultural characteristics of the region and the environmental characteristics of the surroundings. Third, beginning from a concept that explains the complex to a concept that explains individual buildings, it is necessary to reflect characteristics in which the realization of a traditional space is planned in three dimensions.