• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.379-384
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• 2001

This paper presents the experimental result of composite basement wall in which H-pile and reinforced concrete wall are combined using shear connector. Twelve specimens are tested to evaluate the shear capacity of the wall. Main variables in the test are composite ratio, arrangement of shear connector, thickness of wall, shear span ratio, and shear reinforcement. Test results indicate that the shear capacity of test specimens varies with the foregoing variables except the composite ratio. The results are compared with strengths predicted using the equations of ACI 318-99, Zsutty, and Bazant. Based on this investigation, a method for predicting the shear strength of composite basement walls is proposed.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.603-608
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• 2001

In these days, high-strength steel prevails throughout the construction fields for the benefit of structural and economical aspects. But high-strength steel is used by the simple calculation of flexural capacities for the purpose of reducing flexural reinforcement. So, this paper is mainly focused on the shear behavior of high-strength steel reinforced concrete beams without stirrups comparing with normal-strength steel reinforced concrete beams. Specimens were made and tested with the experimental parameters, such as steel yield strength, reinforcement ratios and minimum shear reinforcement. The main result was that not only area but also the yield strength of flexural reinforcement should be considered to predict the shear capacities of concrete beams.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.417-422
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• 2001

This paper is investigated the coupling effect in slab-wall structural system. An experimental investigation of reinforced concrete wall-slab structures were peformed. For the purpose of this study slab-wall substructures of an apartment building were chosen. And two specimens with different aid ratios have been tested. There were subjected to reserved cyclic loading, consistent with coupling action, with increasing imposed inelastic deformations. From. the result of this test, 1) in slabs, the coupling stress are not uniform across the width, 2) cracks are tending to be concentrated in the regions near the inner edges of the walls, 3) the effective width used in previous theoretical or model studies may not be enough.

• Journal of Information Technology Applications and Management
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• v.19 no.2
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• pp.197-215
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• 2012

SNS has been recognized as a means of expanding social capital by promoting interaction and efficient communication among users. On the other hand, there are serious concerns on negative side of social network which is often called epidemics. Trust plays a critical role in controlling the spread of distorted information and vicious rumor as well as reducing uncertainties and risk from unreliable users in social network. This study focuses on what the antecedents of interpersonal trust are in social network. We performed online survey from 252 Twitter users and tested candidate antecedents which are chosen from previous literature. As a result, propensity to trust of trustor, ability and sincerity of trustee, intimacy between trustor and trustee significantly affected to the interpersonal trust in Twitter.

• Proceedings of the Korean Geotechical Society Conference
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• 1999.10a
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• pp.217-223
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• 1999

Mostly, water leakage took place in construction joints. In case of cable tunnels constructed by open-cut method, waterstops have been used to prevent the water leakage. But, we haven't any experience to install the waterstops in NATM cable tunnels. So, it is necessary to develope the waterstops and test the performance of it in laboratory. We manufactured cable tunnel lining quarter scale model by pouring concrete, and installed the waterstops. After filling the inside of concrete lining about two-third with water, we put the air pressure on the water, In addition, it is also carried out water leakage test for concrete lining model without waterstops. As a result, we confirmed the performance of waterstops and its adaptability. It is also tested that the performance of rubber gaskets used in concrete segments of Shield tunnelling. In addition, we determined the allowable infiltration rate for cable tunnel with non-drainage system.

• 유체기계공업학회:학술대회논문집
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• 2002.12a
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• pp.284-289
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• 2002

The objective of this study is to document the secondary flow and the total pressure loss distribution in the contoured endwall installed linear turbine cascade passage and to propose an appropriate height of the contoured endwall which shows the best loss reduction among the simulated contoured endwall. In this study, three different contoured endwalls have been tested which have different height. This study was performed by numerical method and the result showed the contoured endwall which has the height of $5\%$ of the axial chord showed the best loss reduction rate.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.4 no.1
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• pp.12-17
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• 2004

This study is designed to grope for logical methods in the decision-making process of human beings such as creation and analysis. With this in mind, the paper worked with a process where the designers of a design team gather and analyze their opinions in a design process to decide on the HVAC system of buildings. The paper introduced the fuzzy theory, or one of the methods to quantitatively describe language values with ambiguous features, suggesting a method to determine the judgement and suggestion values of the HVAC designers with the characteristics of language variables as the values of design factors greatly influencing the HVAC system. As a result, the paper tested the possibility of the fuzzy system as a logical method to gather the judgement of HVAC designers in a stage of HVAC type selection exerting a great influence on the experience and judgement of the designers and having powerful linguistic features and to determine an appropriate HVAC type which can satisfy the suggested values of related design factors.

• Journal of electromagnetic engineering and science
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• v.12 no.1
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• pp.20-25
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• 2012

In this paper, the EM wave absorber for ETC system was designed and fabricated. We fabricated several samples in different composition ratios of flaked sendust and CPE(Chlorinated Polyethylene). Absorption abilities were simulated in accordance with different thicknesses of the prepared absorbers and changed complex relative permittivity and permeability according to composition ratio. The optimized mixing ratio of flaked sendust and CPE was found as 60 : 40 wt.% by experiments and simulation. Then the EM wave absorber was fabricated and tested using the simulated data. As a result, the developed EM wave absorber has the thickness of 2.75 mm and absorption ability was 22.5 dB in the case of normal incidence at 5.8 GHz. Therefore, it was confirmed that the newly developed absorber can be used for ETC system.

• JSTS:Journal of Semiconductor Technology and Science
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• v.12 no.3
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• pp.293-296
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• 2012

SOC test methodology in ultra deep submicron (UDSM) technology with reasonable test time and cost has begun to satisfy high quality and reliability of the product. A novel hierarchical test architecture using IEEE standard 1149.1, 1149.7 and 1500 compliant facilities is proposed for the purpose of supporting flexible test environment to ensure SOC test methodology. Each embedded core in a system-on- a-chip (SOC) is controlled by test access ports (TAP) and TAP controller of IEEE standard 1149.1 as well as tested using IEEE standard 1500. An SOC device including TAPed cores is hierarchically organized by IEEE standard 1149.7 in wafer and chip level. As a result, it is possible to select/deselect all cores embedded in an SOC flexibly and reduce test cost dramatically using star scan topology.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.11a
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• pp.63-66
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• 2002

In this study, it does a high volume flyash substituted concrete experiments in two curing temperature circumstances - 35$^{\circ}C$, 2$0^{\circ}C$. High volume flyash concrete is tested in fresh concrete properties and hardeded concrete properties. In the fresh concrete test items, there is slump, air contents, concrete setting tests. 3, 7, and 28 days water curing compressive strength is measured in the hardened concrete test. The purpose of this study is to submit a various flyash concrete data for application to field. The result of this study is that the best strength is developed at the plain concrete cured 2$0^{\circ}C$ and Mixing F43 shows the best strength among specimens which cured at 35$^{\circ}C$