• Journal of the Korea Institute of Building Construction
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• v.22 no.1
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• pp.45-55
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• 2022

Ultra-low shrinkage concrete is very effective for securing the quality and appearance of a concrete structure because it can control the drying shrinkage cracks of the concrete structure to within a certain limit. In this study, with the purpose of commercializing ultra-low shrinkage concrete, the optimal amount of expansive agent and shrinkage reducing agent was determined through a lab test, and a concrete wall mock-up test was conducted to examine the shrinkage properties and crack control effects of ultra-low shrinkage concrete. As a result, it was confirmed that there was little drying shrinkage deformation in the wall specimen, and furthermore that no cracks were generated.

• The Journal of the Acoustical Society of Korea
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• v.28 no.1E
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• pp.9-15
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• 2009

In this paper, FSTL (Field Sound Transmission Loss) measured in a mock-up simulating ship cabins is studied. A mock-up is built by using 6 mm steel plate, and two identical cabins are made where 25 mm or 50 mm sandwich panel is used to construct wall and ceiling inside the steel structure. Various wall panels and ceilings are tested, where effects of wall and ceiling panel thickness, and presence of a unit toilet on FSTL are investigated. It is found that the effect of unit toilet on FSTL is at most 1 dB. From the comparison of FSTL for panels of the same thickness of 50 mm, it is observed that panel having inside air cavity of 10 mm shows higher STL than that of the panel without air cavity. Comparison of FSTL for panels of 50 mm and 25 mm thickness shows that dependency on surface density predicted by mass law is not observed. The sandwich panels act as a mass-spring system, which shows a resonant mode that cannot be explained by the mass law. It is also found that STL from laboratory test is higher than FSTL by 5- 10 dB, which can be explained by flanking structure-borne noise transmission path such as ceiling, floor and corridor-facing wall.

• Journal of the Architectural Institute of Korea Structure & Construction
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• v.34 no.3
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• pp.43-52
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• 2018

This study is conducted to evaluate the performance of ceramic panels and painting materials for humidity control which are developed in non-plastic room temperature hardening structure as part of a project to improve a residential environment for the low-income class, rather than the performance of high-priced humidity control materials that are produced with the existing plasticity processing. The testing methods included the measurements of absorption & desoprtion of humidity per material; Mock-up Testing; an evaluation method of comparing the absorption & desoprtion performances of Ecocarat, ceramic panels and painting materials through Living Lab. According to the measurements of absorption & desoprtion per material, ceramic panels, E panel, and ceramic painting material showed 73.3g/m2, 96.6g/m2, and 111.1g/m2, respectively. That is, the performance of humidity control of each material was found to be good in the order of: Ceramic Paint > E panel > Ceramic Panel. According to performance evaluation testing with Mock-up test and Living Lab, Ceramic Paint, Ecocarat, and Ceramic Panels showed better absorption & desoprtion performances in the order.

• Elastomers and Composites
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• v.35 no.2
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• pp.138-148
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• 2000

In order to investigate the possibility of EPDM micro cellular pad (MCP) as an impact sound insulation product, we studied static/dynamic properties and vibration transfer characteristics of EPDM MCP depending on shape, thickness, degrees of foaming by using material test system (MTS) and lab scale mock-up test apparatus. Static/dynamic rigidity is increased when shape is simple. thickness and degrees of foaming low. We could see that dynamic stiffness is proportional to the transmissibility of EPDM MCP. When dynamic stiffness is increased, characteristic peak at transmissibility curve moves high frequency range or snows increase of maximum value of transmissibility. For lab scale mock-up test and finite element method, EPDM MCP shows low vibration velocity and superior mode shape to just concrete plus slab structure. We could confirm that possibility of EPDM MCP as a impact sound insulation product is high.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.361-364
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• 2005

This study reports the properties of high early strength of concrete using PC admixture. To apply these data to construction site, we did the lab tests and mock-up test. The target of this study is to accomplish early strength of concrete(5 MPa/18 hr), and we tested by the different factors, such as the type of admixtures, curing temperature, the amount of binder, etc. Through the test of concrete using the different type of admixture, PC type was more excellent than PNS type admixture. According to these tests, we concluded that we can apply this type of PC Admixture to the civil & construction site, and we can reduce the term of works and finally we can accomplish the economical construction.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.1
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• pp.69-73
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• 2018

Korean-peacekeeper's transparent armors in Iraq showed delamination, cracking and clouding a decade ago. And there were also similar deterioration recurrences in KLTV during the operational test a few years ago. Also, the differences between operational capability & lab Bullet-proof test condition, and insufficiency of military protection spec resulted in incomplete bullet-proof results. Moreover, although so many ground weapon systems have been developed, there were not secure test & evaluation codes to verify transparent armoured glasses equal to advanced-overseas products. So in this study, first, environmental test codes were established that all tests should be carried out as the application of only one specimen with newly adopted thermal shock test instead of completing each test with different one. Second, protection standards were integrated through the analysis of global developed country's specifications and reinforced as adding to the real mock-up condition if vehicle's glasses are smaller than standard specimen. Hereby, by applying to test-codes which including actual operational & vehicular conditions, the gap between development test and operational environment was minimized.

• Nuclear Engineering and Technology
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• v.47 no.6
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• pp.776-790
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• 2015

Background: The advanced spent fuel conditioning process facility (ACPF) of the irradiated materials examination facility (IMEF) at the Korea Atomic Energy Research Institute (KAERI) has been renovated to implement a lab scale electrolytic reduction process for pyroprocessing. The interior and exterior structures of the ACPF hot cell have been modified under the current renovation project for the experimentation of the electrolytic reduction process using spent nuclear fuel. The most important aspect of this renovation was the installation of the argon compartment within the hot cell. Method: For the design and system implementation of the argon compartment system, a full-scale mock-up test and a three-dimensional (3D) simulation test were conducted in advance. The remodeling and repairing of the process cell (M8a), the maintenance cell (M8b), the isolation room, and their utilities were also planned through this simulation to accommodate the designed argon compartment system. Results and conclusion: Based on the considered refurbishment workflow, previous equipment in the M8 cell, including vessels and pipes, were removed and disposed of successfully after a zoning smear survey and decontamination, and new equipment with advanced functions and specifications were installed in the hot cell. Finally, the operating area and isolation room were also refurbished to meet the requirements of the improved hot cell facility.