• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.11a
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• pp.21-23
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• 1994

By adding La₂O₃ to optical multicomponent glass composition, after making mother glass and core fiber that enable to enlarge the infrared transmittance region, then surveyed the optical properties. Through thermal analysis of the glass abstained by melt-quenching after selecting stable basic composition on devitrification and replace SiO₂ by 4-12wt% La₂O₃. As La₂O₃ increases up to l2wt% transition temperature, refractive index, density, deformation temperature increased, whereas thermal expansion coefficient decreased. As a result of inspectig transmittance in UV/VIS/IR region, visable region indicated the decrease of transmittance by increasing the La₂O₃ and transmittance region was enlarged by increasing the La₂O₃ in IR region. Also, fabricate core fiber at 820℃ and severy the optical loss we could fact that La₂O₃ composition added 12wt% showed the minimum optical loss.

• The Research Journal of the Costume Culture
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• v.31 no.1
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• pp.107-123
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• 2023

This research studied the electrical characteristics, IR transmission characteristics, stealth functions, and thermal characteristics of infrared thermal-imaging cameras of copper-sputtered samples. Nylon samples were prepared for each density as a base material for copper-sputtering treatment. Copper-sputtered NFi, NM1, NM2, NM3, NM4, and NM5, showed electrical resistance of 0.8, 445.7, 80.7, 29.7, 0.3, and 2.2 Ω, respectively, all of which are very low values; for the mesh sample, the lower the density, the lower the electrical resistance. Measuring the IR transmittance showed that the infrared transmittance of the copper-sputtered samples was significantly reduced compared to the untreated sample. Compared to the untreated samples, the transmittance went from 92.0-64.1%. When copper sputtered surface was directed to the IR irradiator, the IR transmittance went from 73.5 to 43.8%. As the density of the sample increased, the transmittance tended to decreased. After the infrared thermal imaging, the absolute values of △R, △G, and △B of the copper phase increased from 2 to 167, 98 to 192, and 7 to 118, respectively, and the closer the density of the sample (NM5→NFi), the larger the absolute value. This proves that the dense copper phase-up sample has a stealth effect on the infrared thermal imaging camera. It is believed that the copper-sputtered nylon samples produced in this study have applications in multifunctional uniforms, bio-signal detection sensors, stage costumes, etc.

• Transactions of the Korean hydrogen and new energy society
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• v.12 no.3
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• pp.201-209
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• 2001

The change of optical transmittance of $PdH_x$ thin film due to hydrogen concentration change was measured at room temperature. Pd film($312{\AA}$ thick) was made by thermal evaporation on glass substrate. Hydrogen absorption and desorption cycling effect on optical transmittance was measured 4 times in the pressure range between 0 and 640 torr. Ratio of optical transmittance to the change of ln pressure(torr) increases with increasing number of hydrogen A-D cyclings in the ${\beta}$ phase.

• Laser Solutions
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• v.2 no.2
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• pp.18-26
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• 1999

An innovative real-time weld monitoring technique using chromatic filtering of the thermal radiation from a weld pool is developed. The thermal radiation from the weld pool is focused on an aperture and the transmitted thermal radiation is monitored at two wavelengths with high-speed single-element detectors. Due to the chromatic aberration introduced in the focusing optics, the transmittance curve of thermal radiation varies by the wavelength. Owing to this difference in the transmittance, the local variation of thermal radiation from the weld pool can be monitored by processing the two spectroscopic signals from two detectors. In this paper, the algorithms to monitor the laser power on the weld specimen and the focus shift we investigated and the performances of laser power and focus monitoring are shown for a pulsed Nd:YAG laser welding. The monitoring of the weld pool size variation is also discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.6
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• pp.471-474
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• 2020

In recent years, the challenge of higher energy efficiency has emerged as urban buildings have become taller, and the area of window glasses has increased. To address the problem of energy efficiency in buildings, research on smart windows is being actively conducted. In this study, an accelerated experiment for thermal stability was conducted to fabricate a liquid crystal cell applicable to external windows. It was confirmed from the study that the function is maintained even in a high-temperature external environment through the change in transmittance by voltage. Compared with the initial transmittance, after the passage of time, the smart window cell to which the sealant was applied showed a small change in transmittance of 1~2%. This result confirmed the thermal stability of the liquid crystal-based smart window.

• Land and Housing Review
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• v.5 no.4
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• pp.315-323
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• 2014

In this study, thermal transmittance which is a parameter to measure the thermal performance was evaluated for an internal insulation versus an external insulation. Then the ISO regulation was applied to evaluate it, and the superiority of an external insulation was verified by the thermal transmittance values. The three zones of apartment housing were selected to evaluate the performance. (1) The junction of an outer wall and a protruded slab : If there is no a thermal bridge protection system, then the values are about same in the two insulation systems, so the protection system should certainly be installed. If it is installed, then the value for the external insulation is 2 times lower than internal system. (2) The junction of a side wall and a flat slab: The value is 0.509W/mK for the internal insulation and about zero for the external insulation. (3) The junction of an outer wall and a division wall: The value is 0.451W/mK for the internal insulation and also about zero for the external insulation. A domestic regulation that could evaluate a thermal transmittance has to be established by applying the ISO regulation for the evaluation of external insulation systems in apartment housing in the future. Additionally, the government must decide which length should be used for the national standard.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2012.05a
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• pp.49-50
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• 2012

• Journal of the Korean Society for Heat Treatment
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• v.36 no.3
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• pp.115-120
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• 2023

ZnO/Cu/ZnO (ZCZ) thin film deposited on the glass substrate with DC and RF magnetron sputtering was rapid thermal annealed (RTA) and then effect of thermal temperature on the opto-electical and transparent heater properties of the films were considered. The visible transmittance and electrical resistivity are depends on the annealing temperature. The electrical resistivity decreased from 1.68 × 10^-3 Ωcm to 1.18 × 10^-3 Ωcm and the films annealed at 400℃ show a higher transmittance of 78.5%. In a heat radiation test, when a bias voltage of 20 V is applied to the ZCZ film annealed at 400℃, its steady state temperature is about 70.7℃. In a repetition test, the steady state temperature is reached within 15s for all of the bias voltages.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.946-948
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• 2006

It is important to keep a constant transmittance of dielectric during firing. To control the shrinkage and fusion stage of frits in firing, we used a hot stage microscope (HSM) to analyze the thermal properties of the lead and bismate glass frits by the in-situ method. This research would be useful for improving the reliability of transmittance of dielectric during firing in industry using a large furnace with temperature deviation.

• KEPCO Journal on Electric Power and Energy
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• v.6 no.2
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• pp.151-155
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• 2020

In this paper, a new experimental method to determine the thermal resistance of building wall was proposed by improving the heat flow method (HFM) based on the air-surface temperature ratio theory. This technique measures the thermal resistance of the wall excluding the inner and outer surface heat transfer resistance. Unlike conventional HFM, this value can be compared directly with the theoretical reference value. Its performance was verified using three mock-up structures with a theoretical thermal transmittance of 0.5, 3.3, and 0.18 W/㎡·K respectively. After measuring the variations in the temperature and heat transfer rate of the mock-ups for 383 hours, the thermal transmittances were determined to be 0.47, 3.10, and 0.18 W/㎡·K, which corresponded to errors of 5.2, 6.2 and 0.5%, respectively, compared to the theoretical values. It was concluded that this technique can directly compare the thermal resistance of the wall between the existent stage and initial stage after construction.