• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.29-32
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• 2006

Different from new or reconstruction of an apartment housing, the structural safety in the remodelling construction can be obtained through the repair and strengthening process based on the safety diagnosis and evaluation of structural performance. In this study, structural performance of existing members such as, reinforced concrete slabs, beams and columns are investigated through experimental tests. The structural members were obtained from the existing apartment housing which will be demolished. Test results showed that most specimens have a sufficient structural capacity except for some special case, for example, specimens with severe cracks or concrete loss due to improper casting. This same severe deteriorated or defective structure members originated from bad concrete casting or careless construction process should be repaired and strengthened before an remodelling construction.

• Proceedings of the Korean Fiber Society Conference
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• 1999.04a
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• pp.300-304
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• 1999

A study is strength analysis of a filtering structure for a viscoelastic flowing substance. Conventional segment type filter units comprise an assembly of two or more individual disc segments stacked at their respective hubs on a central common filtrate collection tube within a filter housing. The conventional type's leaf disc is problem that it don't support a high pressure flows. Therefore, this study develope new structure filtering model to stand a high pressure flows.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.296-301
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• 2000

Bend test for metallic materials was conducted on samples of galvanized steel pipes being used in greenhouse farms. A secular change of yield strength for galvanized steel pipes was analyzed with the part of buried in the ground and exposed in the atmosphere. From those experimental results and corrosion rate of galvanized film, the standard durable years for pipe framed greenhouses are estimated that the small sized pipe houses of movable type is 7∼8 years and the large sized pipe houses of fixed type is 14∼15 years.

• Journal of the Economic Geographical Society of Korea
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• v.25 no.1
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• pp.183-201
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• 2022

Estimating the implicit value of housing assets is a very important task for participants in the housing market. Until now, such estimations were usually carried out using multiple regression analysis based on the inherent characteristics of the estate. However, in this paper, we examine the estimation capabilities of the Artificial Neural Network(ANN) and its 'Deep Learning' faculty. To make use of the strength of the neural network model, which allows the recognition of patterns in data by modeling non-linear and complex relationships between variables, this study utilizes geographic coordinates (i.e. longitudinal/latitudinal points) as the locational factor of housing prices. Specifically, we built a dataset including structural and spatiotemporal factors based on the hedonic price model and compared the estimation performance of the models with and without geographic coordinate variables. The results show that high estimation performance can be achieved in ANN by explaining the spatial effect on housing prices through the geographic location.

• Transactions of Materials Processing
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• v.19 no.8
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• pp.447-451
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• 2010

In this paper, a useful die system for warm plate forging of a large axle housing of heavy-duty trucks is presented. A die system composed of material flow guide pin as well as upper die and lower die is proposed to reduce the inherent thickness reduction along the bent corner of the product which deteriorates structural strength and fatigue life in its service. The role of the pin assembled in the upper die is to prevent formation of sharp corner in early forming stage and to supply material in the lower die cavity sufficient enough to thicken the bent corner at the final stroke. The mechanism of the die system is given and its effect on corner thickness of the product is revealed by two-dimensional finite element analysis under plain strain assumption. Three-dimensional finite element solutions are also given to verify validity of the two dimensional approach and to show the mechanics of the die system in detail. The die system has been successfully applied to manufacturing the axle housing of heavy-duty trucks.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.5
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• pp.133-143
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• 2019

Various problems regarding the wet floor method such as its complicated process and waste of thermal storage have been raised, but the usage of dry floor recommended for long-life housing has declined due to lack of confidence on the performance of dry floor. The purpose of this study is to secure the credibility of dry floor. Under this purpose, this study considered precedent studies and established directions to secure the performance of long-life housing infill, and thus, 9 performance items (Impact sound, Smoothness, thermal comfort, sensation hardness while walking, falling safety, impact resistance, local compression load, local strength and strain at heating) were drawn. In addition, the experiment was carried out for 5 performances except for legal performance, some dry floor performances and whole spatial performance. As a result, an appropriate result from all performances except was obtained. The performance of dry floor was verified for each item from these results and it is expected to use such results as basic data on dry floor in the future.

• Journal of the Korean Geotechnical Society
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• v.34 no.12
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• pp.29-42
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• 2018

Shale and mudstone in Daegu-Gyungbuk area have low strength and resistance to weathering compared to other rocks. Therefore, it is necessary to evaluate their strength depending on the degree of saturation and crack development. In this study, shales and mudstones were collected from several construction sites in Daegu-Gyungbuk area. Their basic material properties such as porosity, SEM, chemical component, and durability were tested. A porosity (absorptivity) of mudstone was 31% (25%), which was 6 (8) times higher than that of shale. Some mudstone was easily disintegrated with water and it consisted of highly-active clay mineral such as smectite type. These rocks were prepared by small cube specimens for unconfined compression test. An unconfined compressive strength of dry rock was compared with saturated one. Microwave oven was operated step by step to stimulate void water within a saturated rock, which resulted into high temperature and micro crack initiation within rocks. A strength of microwaved rocks was compared with operation time and crack initiation. As a result, the average unconfined compressive strength of dry and saturated shale was 62 and 33 MPa, respectively. The strength of mudstone for each condition was 11 and 4 MPa. When a rock became saturated, its strength decreased by 47% and 64% for shale and mudstone at average. In addition to saturation, a rock was in the microwave for 15 secs, its strength decreased into 49% for shale and 52% for mudstone. When a microwave oven operated up to 20 sec, a rock was crushed into several pieces and its temperature was approximately 200 degrees.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.189-194
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• 1995

This paper presents the material properties and production of 500 and 700 kg/$\textrm{cm}^2$ high strength concrete for the practical utilization. A series of Lab. tests were conducted to optimize the material mixture of high strength concrete and then mock-up tests were performed through the Remicon Batch Plant. This paper stresses the material conditions for the final stage of production of 500 and 700 kg/$\textrm{cm}^2$ high strength concrete, just prior to the practical use on 28-story Samsung Shin-Daebang Housing-Commercial Combined Building with 8-story basements.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.10a
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• pp.262-266
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• 1995

This paper present the application and construction characteristics of Ultra-High Strength Concrete on Samsung Sin Dae-Bang Housing-Commercial Combined building with 28 story including 8 story basement in seoul. 1200kg/ $\textrm{cm}^2$compressive strength has been placed for paraphet at lst floor for experimental purposes. 420kg/$\textrm{cm}^2$ design strength concrete was used for other basement and frame up to 10th floor which is used for commercial purposes.

• Land and Housing Review
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• v.4 no.3
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• pp.295-301
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• 2013

In this study, cases of domestic tall residential buildings were investigated for the structural types, numbers of stories, total heights, type of lateral load resisting systems, and zoning of concrete strength. Based on these investigation data, the structural planning pattern of tall residential building was analyzed. SRC structure is main structural types of tall residential building at the initial stage of domestic tall residential building, but RC structure is substituted for main structural types since 2005. Retaining wall system is positioned at the core part of structural plan as a lateral load resisting system. Concrete strength zoning of vertical members like columns are divided by vertical heights of lower parts, middle parts, and upper parts. Basic data of structural planning of 40stories and 60 stories residential buildings was proposed based on case investigation.