• Proceedings of the Korean Geotechical Society Conference
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• 2005.10a
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• pp.443-452
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• 2005

The compaction pile methods with low replacement area ratio used sand(SCP) or gravel(GCP) has been usually applied to improvement of soft clay deposits. In order to design accurately compaction pile method with low replacement area ratio, it is important to understand the mechanical interaction between sand piles and clays and its mechanism during consolidation process of the composition ground. In this paper, a series of numerical analyses on composition ground improved by SCP and GCP with low replacement area ratio were carried out, in order to investigate the mechanical interaction between sand piles and clays. The applicability of numerical analyses, in which and elasto-viscoplastic consolidation finite element method was applied, could be confirmed comparing with results of a series of model tests on consolidation behaviors of composition ground improved by SCP. And,through the results of the numerical analyses, each mechanical behaviors of compaction piles and clays in the composition ground during consolidation was elucidated, together with stress sharing mechanism between compaction piles and clays.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.269-273
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• 2011

In present paper focused on the influence of the inlet-outlet area ratio of counter flow manifold on the flow distribution and pressure drop characteristics of a tubular heat exchanger. The characteristics of flow distribution and pressure loss can be obtained depending on the inlet-outlet area ratio. In this paper, a tubular heat exchanger can be designed with minimum flow mal-distribution and better characteristic of pressure loss by choosing the optimum inlet-outlet area ratio.

• KIEAE Journal
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• v.5 no.3
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• pp.17-24
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• 2005

Until today, rainwater management was processed without disposing the peak discharge, which was due to rainfall, to provide stability against flood damage. In this process, the natural hydrologic cycle changed quickly, and because of this, some problems that could harm human beings and the environment arose. These problems need to be addressed accordingly. One of the proposals was to carry out decentralized rainwater management through a natural hydrologic cycle on site, including utilization, infiltration, detention, and retention of rainwater. This study aims to set the direction of applicable decentralized rainwater management to housing complex in Korea. Therefore, spacial properties in urban housing complexes were analysed such as the impervious area-to-land ratio, the green area-to-land ratio, artificial land-to-land ratio etc. As the result of this study, when a housing complex was small and developed by reconstruction, the impervious area, artificial land, the green area in the artificial land-to-land ratio were high. So, direction of decentralized rainwater management of these housing complexes is available to utilize and detain rainwater. On the other hand, those of big housing complexes in land development district were low relatively. So, direction of decentralized rainwater management of these housing complexes is available to infiltrate and evaporate rainwater.

• Journal of the Korean Professional Engineers Association
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• v.33 no.2
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• pp.12-17
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• 2000

The rebuilt and redevelopment projects conducted these days surely have invited overpopulation. Its one of the culprits is the municipal ordinances which allow the floor to site area ratio to increase from 200% to 400% in a decade and the adjacent distance ratio from 1.25 to 0.8 times of height of building. Possible solutions for the overpopulation problem are as below. - The floor to site area ratio should be regulated adaptively according to various regional localities. - Draw back the capital gains coming from a rebuilding project For evaluation process; - Select a suitable plan from plurality of proposals - Gradually encourage projects towards remodeling system in the near future

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.2
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• pp.24-31
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• 2008

Studies for demarcation of urban areas by ecological type have been developed, but the demarcation of urban areas by ecological perception is thus far dependent on artificial land use. Therefore, the purpose of this study is to find factors that account for the urban area ecosystems by surveying a variety of ecosystem factors. By land use type, the urban area of Gangdong District, Seoul was defined. Then ecological factors in each polygon were surveyed. Ecological factors are associated with energy use(building coverage ratio, floor area ratio and ground temperature), water circulation(biotope area factors and impermeable pave ratio) and biological diversity(bird appearance index and green area ratio). The correlation between each factor was analyzed. The results indicate that urban ground temperature is divided into three groups(high, middle and low) by the biotope area factor. The bird population is divided into two groups(abundant and scarce) by the green area ratio. Therefore, demarcating the urban areas by ecological type is applicable to the biotope area factor and green area ratio.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.1
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• pp.61-68
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• 2018

This study aims to investigate the changes in area ratios by space through floor plans of national leasing houses constructed by the LH in Jangseong-gun, particularly focusing on the floor plans of public leasing housing complexes built during the 1970s-80s and those during the 2010s. The results are as follows: First, according to the composition ratio of floor plans by period, the type of Bedroom> Livingroom> Common Area> Kitchen+Dining> Multi-purpose room> Bathroom> or the type of Bedroom> Livingroom> Kitchen/Dining> Common Area> Bathroom> Multi-purpose room were found to be high during the 1970s. Whereas, the type of Common Area>Living room(Kitchen/Dining included)>Bedroom>Bathroom>Front Entrance was found to be high during the 2010. It can be concluded that the ratio of Bedroom and Living room was found to be high during the 1970s, but after 2010s, the spacial composition ratio of Common Space, Living room, and Bedroom is getting higher in the order. Second, in terms of the composition ratio of floor plans by the area of unit household, among the floor plan of C-1, B-2, B-3, C-2 which were used since 2010s, the spatial ratio of Bedroom was maintained in the range of 20%; while during the 1970s, the Bedroom space of A-1(46%), A-2(46%), and A-3(41%) was found to be higher than 40%. It can be concluded that the size of bedroom space has doubled over time. In terms of the changes in the spatial ratio of Living room, A-1(15%), A-2(22%), and A-3(23%) were found during the 1970s. Compared to the recent floor plans of C-1(28%), B-2(25%), B-3(33%), and C-2(34%) which are applied in Jangseong-gun, Jeollanam-do province, no big changes have been found, particularly in the small floor plans (20% range).

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.82-89
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• 2004

To secure stability and availability of Rammed Aggregate Pier method as the foundation of a structure, the shear strength characteristics according to the area replacement ratio of RAP and the relative density of in-situ ground was studied through soil laboratory tests and large direct shear tests in a model ground. As a result, the internal friction angle tends to increase in proportion to in-situ relative density(Very Loose, Loose, Medium) in composite ground formed by the same area replacement ratio of RAP and also increase in proportion to increasing the area replacement ratio(30, 40, 50%) of RAP in the same ground condition. Furthermore, the comparative analysis between the experimental value and theoretical value of the shear strength is carried out.

• Journal of the Korean housing association
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• v.14 no.5
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• pp.11-17
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• 2003

This study is aimed at analyzing on the sunshine according to the blocks direction by location type of apartment complex in Busan, to propose a planning on the decision of blocks direction and the improvement of architectural law in sunshine environment. The results of this study were as follows; On the basis of winter solstice in "□ block type", the average of ratio of shadow area in flat site is 51 % in apartment with a southern exposure, 39% in apartment with a south-eastern exposure. The average of ratio of shadow area in the descended site toward the north is 49% in apartment with a southern exposure, 34% in apartment with a south-eastern exposure. The average of ratio of shadow area in the descended site toward the south is 66% in apartment with a southern exposure, 53% in apartment with a south-eastern exposure.

• 한국연소학회:학술대회논문집
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• 2015.12a
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• pp.147-150
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• 2015

When high-pressure gas is suddenly leaked out into the air, unexpected ignition occurs without any external ignition source. Until now, there have been investigations on self-ignition of hydrogen by supplying high-pressure hydrogen gas into a tube. However the mechanism of hydrogen ignition is still unclear. This paper describes the area-ratio effect on hydrogen ignition by inserting a brass plate. The results show that the ignition phenomena differ as the area-ratio changed. Also, the rupture pressure for self-ignition has to be higher.

• International Journal of High-Rise Buildings
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• v.12 no.3
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• pp.195-201
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• 2023

This paper reviews the history of the birth and development of the skyscraper in Japan, mainly from the perspective of the legal system, and presents the following points: 1) After 1919, building height was limited to 31 m or less, which continued after the war and defined the skyline of Japan's major cities; 2) The 31-meter height limit became a problem during rapid economic growth. With the development of tall building construction technology, the height limit was eliminated, and skyscrapers were born in Japan in the 1960s; 3) Later, the number of skyscrapers increased more rapidly in the post-bubble period after the collapse of the bubble economy in the 2000s than in the boom years of the 1980s, when the floor-area ratio was relaxed for economic uplift and urban renewal. The number of skyscrapers increased rapidly against the backdrop of the deregulation of the floor-area ratio.