• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.4
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• pp.18-24
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• 2012

In this study, hybrid method using polyvinyl acetate (PVAc) which has a strong adhesion and flexibility in which acrylic copolymer chemical-reaction reacts with cement, and is eco-friendly, is to improve the watertightness. The hybrid method is applied applied primarily waterproof stuff comprising silicate system and secondary mortar mixed with PVAc on the concrete surface. And then, in order to evaluate the performance, the properties of bond strength and amount of water absorption were measured. Based on the above experiments, mock-up specimens for field application were fabricated, and then the properties were evaluated as laboratory experiments. As the results, specimens cast from hybrid method using PVAc showed the best results on watertightness and bond strength. And also, with respect to experiment of mock-up specimens, the properties were in agreement with laboratory results. Especially, it could know that PVAc has strengthening effect from the results of the compressive strength. Due to outstanding results of carbonation depth and resistance to chloride ion penetration, it may be applied in weak areas such as underground and marine structures.

• The Journal of the Acoustical Society of Korea
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• v.38 no.2
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• pp.193-199
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• 2019

In this paper, the results of underwater vibration experiment are analyzed to verify platform vibration-induced noise isolation characteristics of a hull-mounted acoustic sensor. The experimental condition causing platform vibration-induced noise is generated using the mock-up hull, where the acoustic sensor is installed, with shaker in an acoustic water tank. The performance indices of ATF (Acceleration Transfer Function), AVS (Acceleration Voltage Sensitivity), and IL (Insertion Loss) for the acoustic sensor are calculated from the output of the standard accelerometers, which are installed on the mock-up hull and the acoustic sensor, and the output signal of the acoustic sensor. The frequency-dependent noise isolation characteristics of the acoustic sensor are analyzed based on the calculated performance indices and an effectiveness of the experiment is examined.

• Proceedings of the KIEE Conference
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• 2001.11a
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• pp.189-191
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• 2001

This paper described the outputs of acoustic sensors due to the vibration of particles in the mock up GIS. We used the two type of acoustic sensors which had 150kHz resonant frequency and 60kHz resonant frequency respectively. In the experiment of the mock up GIS we paid attention to the relationship between applied voltages and sensor outputs due to particles. In this results fall down voltages depended on the material and length of particles but lift off voltages depended on the materials of particles. And the sensors outputs were increased with applied voltages in the same particle.

• 한국태양에너지학회:학술대회논문집
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• 2008.04a
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• pp.148-153
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• 2008

An inflow of daylight to the room offers comfortable view environment, psychological and physical security to people in the room and there are merits such as a work efficiency and energy saving. But, it has many problems as an excessive direct sunlight, cooling and heating. We can expect to have energy saving effect for illumination with comfortable view environment creation through control on height of roller shade. This study will be a used a fundamental approach to control on height of roller shade to changing daylight.

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1646-1648
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• 2001

This paper described the outputs of acoustic sensors due to the vibration of particles in the mock up GIS. We used the two type of acoustic sensors which had 150kHz resonant frequency and 60kHz resonant frequency respectively. In the experiment of the mock up GIS, we paid attention to the magnitude and attenuation of sensor outputs due to particles. In this results the output of each sensor in frequency characteristic depended on the material of GIS tank and the output of sensor in magnitude characteristics depended on the size of particles and dropping height.

• Proceedings of the KSR Conference
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• 2007.05a
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• pp.430-437
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• 2007

The experiments for aerodynamic characteristics on railway acoustic screen are performed using 1/61 scale-down mock-up facility. The train model for the experiment is high speed train (KTX) and the tested speed is about 300km/h. The tested train length is about 61cm which is corresponding to two units of train. The strength of pressure wave is measured using piezo typed pressure sensor. The measured pressure is compared with field test data and UIC 779-1 values.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1742-1744
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• 2002

This paper described the outputs of acoustic sensors due to the vibration of particles in the mock up GIS. We used the two type of acoustic sensors which had 150kHz resonant frequency and 60kHz resonant frequency respectively. In the experiment of the mock up GIS, we paid attention to the relationship between outputs of sensors and particles and we found that the ratios of outputs related with the lengths of particles. We developed the apparatus including the above diagnosis algorithm for GIS.

• International Journal of High-Rise Buildings
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• v.3 no.2
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• pp.147-154
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• 2014

The purposes of this study were to analyze criteria for measurement chamber design dedicated curtain wall, and how to measure of performance configuration and status of the chamber that is currently being used. Main dealing criteria is AAMA 1503-09. Measurement of data is made in curtain wall Mock-up experiment station with thermal imaging camera. Measurement data using thermal imaging cameras at Mock-up curtain was made at the test site. The results of this study were as follows; There is no U-value test method for actual size of curtain wall. The thermal test outdoor chamber showed heat loss in the connection part of indoor and outdoor chamber. And the indoor chamber showed unstable temperature distribution by height.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.241-242
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• 2021

In this study, we develop the damage depth diagnostic technology of fire damage concrete and propose an method of impaired depth due to fire by drying impaired concrete after immersing. Test results indicated that when assesing impared depth due to fire with the dry method after water immersing, impaired depth was clearly found and furthermore, compared with that by Phenolphthalein method 10 mm of damage depth was additionally identified, which is imposible to asses when Phenolphthalein is applied.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.245-246
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• 2021

In this study, we develop the damage depth diagnostic technology of fire damage concrete and propose an method of impaired depth due to fire by drying impaired concrete after immersing. Test results indicated that when assesing impared depth due to fire with the dry method after water immersing, impaired depth was clearly found and furthermore, compared with that by Phenolphthalein method 15 mm of damage depth was additionally identified, which is imposible to asses when Phenolphthalein is applied.