• Journal of Sensor Science and Technology
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• v.25 no.2
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• pp.103-109
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• 2016

Recent light-enhanced metal oxide gas sensors are reviewed in this article. The basic mechanisms of a light-enhanced metal oxide gas sensor are discussed. Many literatures reveal that the standalone sensitivity and the response/recovery time enhancements enabled by the exposing light are not as high as the performance enhancement provided by external heating. Therefore, both optimal amount of external heating and exposed light intensity are necessary to increase the performance of these light-enhanced gas sensors. The development of highly light sensitive materials and structures is important to lower the overall power consumptions of the sensors.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.42 no.6
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• pp.711-720
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• 2009

Characteristics of spectral irradiance based on the distance from the light source, which combined metal halide lamp and high-luminance light-emitting diode (LED) light, were studied to investigate a suitable operating method for fishing lamps of the next generation. A 380-780 nm wavelength radiation was superior when using 1 W electrical power in the order of metal halide lamp, blue LED, white LED, and combined LED lights. The wavelengths at which the irradiance was at a maximum were fixed to 581 nm for the light source, which was combined for each ratio. If the irradiance characteristics at 300-1100 nm wavelengths were set as 100%, the irradiance rates at 400-599 nm were 100%, 72.7%, 88.9%, and 69.5% for the blue, white, combined LED lights, and metal halide lamp, respectively. This indicated that the color rendering of the LED lights was dependent on the metal halide lamp light source. When the horizontal profiles (450-550 nm wavelength) of irradiances were compared to a different type of light source in the ratio white LED: combined LED lights: blue LED: metal halide lamp, the irradiated area of more than $0.01\;{\mu}mol/s/m^2/nm$ was in the ratio 1.0 : 1.3 : 1.7 : 37.3, respectively. Based on the radiation characteristics and irradiance according to the distance from the light source, LED lights have an estimated economic efficiency if used before and after operation of a metal halide lamp.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1995.10a
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• pp.39-46
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• 1995

Metal halide pamp for LCD projector back light is high technologlcal product with its consumption increasing by 30% a year according to LCD merchandise and we are whollydepending on imprtation. At this time exper iment. we achleved those results as below. 1. Reallzation of domestic production of 150W metal halide lamp for LCD progector back light and electrical ballatst. 2. Possession of self-designing and manufacturing technology of submlnlature metal halide lamp. 3. Possession of deslgning technology of electrlcal ballast for metal hallde lamp.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.387.1-387.1
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• 2016

Transparent materials are necessary for most photoelectric devices, which allow the light generation from electric energy or vice versa. Metal oxides are usual materials for transparent conductors to have high optical transmittance with good electrical properties. Functional designs may apply in various applications, including solar cells, photodetectors, and transparent heaters. Nanoscale structures are effective to drive the incident light into light-absorbing semiconductor layer to improve solar cell performances. Recently, the new metal oxide materials have inaugurated functional device applications. Nickel oxide (NiO) is the strong p-type metal oxide and has been applied for all transparent metal oxide photodetector by combining with n-type ZnO. The abrupt p-NiO/n-ZnO heterojunction device has a high transmittance of 90% for visible light but absorbs almost entire UV wavelength light to show the record fastest photoresponse time of 24 ms. For other applications, NiO has been applied for solar cells and transparent heaters to induce the enhanced performances due to its optical and electrical benefits. We discuss the high possibility of metal oxides for current and future transparent electronic applications.

• Journal of Technologic Dentistry
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• v.42 no.2
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• pp.65-71
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• 2020

Purpose: To know the transmittance of light when wearing shading goggles and to protect eyes from blue light emitted from dental scanner when using CAD/CAM works or inducing polymerization reactions of dental resin with curing unit and infrared light occurred when melting Dental precious metal and non-precious metal alloys. Methods: By measuring and comparing the average transmittances of blue light, visible light and infrared ight by using UV-Vis Spectrophotometer analysis measuring instrument, I compared 3 GREEN Color Goggles worn when casting Dental precious metal and non-precious metal alloys, and compared each of YELLOW, ORANGE Color Goggles worn when using Dental CAD/CAM scanners and Light Curing(LED) the Dental resin. Results: In blue light range, YELLOW Color Goggles are more effective than ORANGE Color Goggles. In infrared light range, No.12 Goggles are more effective than No.10 and No.11 Goggles. Conclusion: When wearing blue light shading goggles to avoid harmful blue light occurred in using dental scanner and curing light, and when wearing infrared light shading goggles to avoid harmful infrared light during casting, to avoid the Side Effects like transmittance rate of blue light and infrared light goggles becomes too high to block appropriate amount of harmful light or too low that causing lower image clarity.

• KIEAE Journal
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• v.13 no.2
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• pp.47-52
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• 2013

The problems of light pollution first became an issue in the 1970s when astronomers identified the degradation of the night sky due to the increase in lighting associated with development and growth. As more impacts to the environment by lighting have been identified, many attempts have been made for reducing light pollutions. To prevent light pollution and increase energy efficiency, Seoul Metropolitan Government(SMG) replaced metal halide road lighting to LED luminaire in four arterial highway in Seoul. The present study compared the lighting characteristics of metal halide and LED luminaire in terms of Korea Standard for road lighting(KS A 3701) and BUG rating from Illuminating Engineering Society of North America(IESNA). The results showed that LED luminaire increased road surface luminance up to 2 times in average compared to the metal halide environment. Also, LED luminaire reduced the glare value by 2 times and luminous flux over 50% than the metal halide luminaire. In comparison with the BUG ratings, LED luminaire rated 1 degree lower for the backlight ratings and 3-4 degrees lower for the uplight ratings. The measured values testified that the LED luminaire is effective for roadway lighting and light pollution reduction.

• Journal of the Semiconductor & Display Technology
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• v.3 no.3
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• pp.31-35
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• 2004

A blue light emitting diode with 8 periods InGaN/GaN multi-quantum well structure grown by metal-organic chemical vapor deposition was fabricated with the inclusion of the metal-interconnection process in order to integrate the chips for light lamp. The quantum well structure provides the blue light photoluminescence peaked at 479.2 nm at room temperature. As decreasing the temperature to 20 K, the main peak was shifted to 469.7 nm and a minor peak at 441.9 nm appeared indicating the quantum dot formation in quantum wells. The current-voltage measurement for the fabricated LED chips shows that the metal-interconnection provides good current path with ohmic resistance of 41 $\Omega$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.41 no.6
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• pp.511-517
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• 2008

The radiation characteristics and economic efficiency of high - luminance light - emitting diodes (LEDs), a metal halide lamp, and a halogen lamp were studied to evaluate their potential as an energy-saving light source for fishing lamps. The wavelengths at which irradiance was maximum were 709, 613, 473, 501, 525, 465, 578, and 973 nm for red, orange, blue, peacock blue, green, and white LEDs, the metal halide lamp, and the halogen lamp, respectively. If the irradiance characteristics at 300-1,100 nm wavelengths are set as 100%, the irradiance rates at 381-780 nm were 99-78%, 82%, and 24% for the LEDs, metal halide lamp, and halogen lamp, respectively. The economic efficiency was superior in the order metal halide lamp, halogen lamp, peacock blue LED, and blue LED at 381-780 nm and metal halide lamp, peacock blue LED, blue LED, and halogen lamp at 480-520 nm. Based on the radiation characteristics and economic efficiency evaluated at 480-520 nm, the blue and peacock blue LED light sources can be used as energy-saving light sources for fishing lamps.

• Environmental Analysis Health and Toxicology
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• v.10 no.3_4
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• pp.7-13
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• 1995

The most periodlengths($\tau$) of conidiation of Neurospora were shortened in the medium with Li$^+$, Rb$^+$, and Cs$^+$ under the blue or green light. The higher the concentration of the heavy metal elements are, the shorter the circadian lengths are. The largest differences between the maxima- and minima circadian lengths showed in the medium with LiCI, RbCl, and CsCI under the blue lights at 150 Lux, while the little differences of circadian lengths presented in 1 mM heavy metal elements at the 270Lux blue light. Li$^+$ under the blue light effected extremely much and in the order of Rb$^+$ and Cs$^+$ on the conidiation of Neurospora. Under the green lights at 270Lux, the smallest changes of the circadian lengths are resulted in the medium with heavy metal elements. The other way at the green light 150Lux, the conidiation is stimulated by lmM LiCI or RbCl for the average 0.71h and 0.29h longer than the periodlength of control 28.34h. The medium with Li$^+$ under the green light has less effect on the conidiation rhythm of Neurospora than with Rb$^+$ or Cs$^+$.

• The korean journal of orthodontics
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• v.31 no.2 s.85
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• pp.261-270
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• 2001

The purpose of this study was to evaluate the clinical usefulness of plasma arc light which can reduce the curing time dramatically compared by shear bond strengths and failure patterns of the brackets bonded with visible light in direct bracket bonding. Some kinds of brackets were bonded with the Transbond$^{\circledR}$ to the human premolars which were embedded in the resin blocks according to the various conditions. After bonding, the shear bond strength was tested by Instron universal testing machine and in addition , the amount of residual adhesive remaining on the tooth after debonding was measured by the stereoscope and assessed with adhesive remnant index(ARI). The results were as follows : 1. When plasma arc light was used for bonding the brackets, the shear bond strength was clinically sufficient in both metal and ceramic brackets, but resin brackets showed significantly lower bond strength but which was clinically useful. 2. When metal brackets were bonded using visible light, there was no significant difference in shear bond strength due to the light-curing time and the bond strength was clinically sufficient. 3. When the adhesive failure patterns of brackets bonded with plasma arc light were observed by using the adhesive remnant index, the bond failure of the metal and resin bracket occurred more frequently at bracket-adhesive interface but the failure of the ceramic bracket occurred more frequently at enamel-adhesive interface. 4. There was no statistically significant difference of the shear bond strength and adhesive failure pattern between metal bracket bonded for 2 seconds by curing with plasma arc light and 10 seconds by curing with visible light. 6. When metal brackets were bonded using plasma arc light, the shear bond strength decreased as the distance from the light source increased. The above results suggest that plasma arc light can be clinically useful for bonding the brackets without fear of the decrease of the shear bond strength.