• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2006.05a
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• pp.363-366
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• 2006

In general, pyrotechnic shock or pyroshock is generated during the operation of separation devices, which use explosives, such as pyrobolt, puronut, purocutter, linear shape charge, and so on. During the flight of launch vehicle, pyroshock is mainly produced at the events of satellite separation, fairing separation and stage separation. In this paper, characteristics of pyroshock are introduced in the first place and measured shock result data at the UMR of satellite mock-up during the separation tests of satellite and fairing are suggested. These results are compared with the suggested pyroshock test specification of satellite, and it finally confirms that the specification is reasonable for the qualification of satellite against pyroshock.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.197-198
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• 2019

The aim of the research is evaluating the feasibility of inspection for early age frozen damage and for expansion of concrete under the various time periods of -20℃ temperature condition. When the concrete samples were exposed for 12 hours and 24 hours, the frozen depth of the concrete were 10 and 60 mm, respectively, under the wet conditions. From the experiment results of temperature and expansion, only surface area suffered frozen damage for 12 hours exposing conditions while entire area suffered frozen damage for 24 hours exposing conditions.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.159-160
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• 2018

In this study, the characteristics of the Mock-up test were reviewed to analyze the applicability of the coal gasification slag (CGS) from the integrated gasification combination Cycle (IGCC) to the concrete fine aggregate. The analysis shows that CGS and crushed sand mix is the best combination of CGS combined with about 50 % of CGS based on the effects of promoting liquidity and strength. This is expected to be a positive factor in securing the strength and flexibility of concrete given the optimal mix of CGS, and may also contribute to the improvement of quality.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.21-22
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• 2018

In this study, the characteristics of the Mock-up test were reviewed to analyze the applicability of the coal gasification slag (CGS) from the integrated gasification combination Cycle (IGCC) to the concrete fine aggregate. The analysis shows that CGS and crushed sand mix is the best combination of CGS combined with about 50 % of CGS based on the effects of promoting liquidity and strength. This is expected to be a positive factor in securing the strength and flexibility of concrete given the optimal mix of CGS, and may also contribute to the improvement of quality.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.11a
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• pp.128-129
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• 2019

In this study, after exposing the normal concrete outside at $-20^{\circ}C$, when the above scored $20^{\circ}C$, we analyzed the limit points of the initial early frost damage to the concrete. As a result, it was confirmed that the degree of the upper part of the concrete when it was exposed outside the freezing point for 6 hours was zero.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.148-149
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• 2021

In Japan, ultra-low shrinkage concrete has been developed and commercialized to control drying shrinkage cracks to the limit. However, in the case of South Korea, the study on this technology has not yet been conducted in earnest. Therefore, the study was conducted for the development of ultra-low shrinkage concrete to control the drying shrinkage crack of concrete to the limit, and in this study, after determining the mixture of ultra-low shrinkage concrete, a wall type mock-up specimen was produced to observe the shrinkage behavior of ultra-low shrinkage concrete.

• Journal of Ocean Engineering and Technology
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• v.30 no.2
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• pp.117-124
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• 2016

A C-type LNG mock-up tank was constructed to evaluate the durability of the tank and its structural safety. An experimental strain analysis system equipped with strain gages was designed to investigate the structural behavior of the inner tank at a high hydraulic pressure. In addition, the insulation used in the space between the inner tank and outer tank had a compressive strength and the inner tank thickness of the cylindrical shell and hemisphere was 4.0 mm, which was designed to be thinner than the existing rules. The strains on the inner tank were measured with increasing pressure, and these measurements were compared and analyzed at the strain gage attachment points.

• Journal of the Korea Society of Computer and Information
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• v.28 no.7
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• pp.1-9
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• 2023

Currently, as the demand for stops in the urban increases resulting from an increase in the supply of express trains, the development of trains capable of operating both high-floor platforms in the urban and low-floor platforms in the suburbs is required. In this paper, we studied the design and fabrication of a controller for train doors that consists of low and high steps as a plug-in type door mechanism and thus can be used on low and high platforms. This DCU H/W was designed and implemented using 32 bit MCU to control 4 motors, 33 digital inputs and 16 digital outputs. In addition, based on the software life cycle of EN50128, 2 items of operation requirements and 12 items of control requirements were derived, and then they were designed and implemented as operation SW. The implemented SW was tested for each requirement. As a result, we performed tests on 13 items that could be tested in the mock-up out of 14 total requirement items and showed that the requirements were satisfied.

• Journal of the Korea Concrete Institute
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• v.16 no.5 s.83
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• pp.613-620
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• 2004

We encapsulate the core materials which have long term resisting properties to the insect. We also try to apply those capsules to the mortar and concrete which is used for the structures and ornament materials. Various membrane structures and sizes of microcapsule are tested and construction properties of the mortar and concrete which contain microcapsules are examined. The capsuled are confirmed by SEM and optical microscope. Finally the microcapsules with anti-insect which can be used for the mortar and concrete are developed through the various experiments and mock-up tests.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.961-964
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• 2008

There are researches in progress on ensuring the safety of the high impact concrete in case of fire which is a current rising social problem and this research institute also developed PFB technology, the explosion preventing technology. PFB technology is to apply POSCO E&C Fire Board, a fireproof board, with an adhesive agent on the construction site, and this technology passed 3-hour fireproof test and this technology was proven from a previous research that the temperature of main root is maintained under $200^{\circ}C$. Therefore, tests on basic contents was performed in this research before the actual construction, with a full scale of wooden prototype to apply PFB technology to actual construction sites and the tests were done on the workability of fireproof board, the adhesive power, the resistance against imprint of wooden nail, the heat conductivity and etc. As the results of these tests, PFB technology was proven to have an excellent workability at a construction site and to be easy for processing and also, this technology was proven to have a great resisting power against imprint of wooden nail. Therefore, this research has confirmed that PFB technology has no problem to be applied on a construction site.