• 제목/요약/키워드: Light metal

검색결과 1,253건 처리시간 0.035초

Recent Trends of Light-enhanced Metal Oxide Gas Sensors: Review

  • Cho, Minkyu;Park, Inkyu
    • 센서학회지
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    • 제25권2호
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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.

이종(異種) 광원 조합에 의한 복수 광원의 분광 방사특성과 광달(光達) 거리 및 집어등 운용방법 (Characteristics of Spectral Irradiance Based on the Distance from the Light Source and Operating Method for Fishing Lamps with a Combined Light Source)

  • 최석진
    • 한국수산과학회지
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    • 제42권6호
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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.

LCD PROJECTOR BACK LIGHT용 METAL HALIDE LAMP의 연구 및 개발 (Reserch and development of metal halide lamp for LCD projector back light)

  • 박창식;정의선;이승수
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 1995년도 추계학술발표회논문집
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    • pp.39-46
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    • 1995
  • LCD. projector back light용 metal halide lamp는 최근 LCD의 고신장세에 편승 매년 30% 정도 수요가 증가하고있는 첨단제품으로 국내에서는 전량 수입에 의존하고 있는 실정이며 본 연구에서는 다음과 같은 기술 성과를 거두었다. 1. LCD projector back light용 150W metal halide lamp및 전자식 안정기의 국산화 완료 2. 초소형 metal halide lamp의 설계기술 및 제작 기반기술 확보 3. Metal halide lamp용 전자식 안정기의 설계기술 확보

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Functional Designs of Metal oxide for Transparent Electronics

  • Kim, Joondong;Patel, Malkeshkumar;Kim, Hong-Sik;Kim, Hyunki;Yadav, Pankaj;Park, Wanghee;Ban, Dongkyun
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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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.

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청색광, 가시광선 및 적외선이 차광보안경에 따라 투과되는 투과율 차이 비교 (Comparison of blue light, visible light and infrared light transmittance difference of shading Goggles)

  • 정인호;이상덕;이숙정
    • 대한치과기공학회지
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    • 제42권2호
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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.

LED램프와 메탈램프가 도로조명환경에 미치는 특성 비교평가 (Effects of LED Lamps for Replacement of Metal Halide Lamp in Roadway Lighting Environment)

  • 이명기;김정태
    • KIEAE Journal
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    • 제13권2호
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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.

금속배선 칩 집적공정을 포함하는 질화물 반도체 LED 광소자 특성 연구 (A Study on the III-nitride Light Emitting Diode with the Chip Integration by Metal Interconnection)

  • 김근주;양정자
    • 반도체디스플레이기술학회지
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    • 제3권3호
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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 $\Omega$.

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고휘도 발광다이오우드와 집어등 광원의 방사특성 및 단위 전력당 방사량 비교 (Comparison of Radiation Characteristics and Radiant Quantities per unit Electrical Power between High Luminance Light Emitting Diode and Fishing Lamp light Source)

  • 최석진
    • 한국수산과학회지
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    • 제41권6호
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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.

Neurospora crassa의 포자형성 주기에 미치는 빛파장과 중금속 이온의 영향 관계 조사 (The Correlation of Wavelengths with Heavy Metal Elements on the Circadian Rhythm Conidiation in Neurospora crassa)

  • 한상진
    • Environmental Analysis Health and Toxicology
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    • 제10권3_4호
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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$^+$.

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Plasma arc light를 이용한 bracket 부착시의 전단결합강도와 파절양상의 유형 (Shear bond strength and adhesive failure pattern in bracket bonding with plasma arc light)

  • 유형석;오영근;이승연;박영철
    • 대한치과교정학회지
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    • 제31권2호통권85호
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    • pp.261-270
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    • 2001
  • 본 연구의 목적은 bracket 부착시 광조사시간을 획기적으로 감소시킬 수 있는 plasma arc light의 임상적 유용성을 visible light 중합시의 전단결합강도와 접착파절양상과 비교해 봄으로써 평가해 보는데 있다. 사람의 상하악 소구치를 포매하여 만든 레진블럭시편에 광중합 접착제인 Transbond$^{\circledR}$를 사용하여 수종의 bracket을 각각의 조건에 따라 부착한 후 만능 물성시험기를 이용하여 전단결합강도를 측정하고, 접착파절양상을 stereoscope을 이용하여 관찰하여 다음과 같은 결과를 얻었다. 1. Plasma arc light를 이용한 수종의 bracket 접착시 metal bracket과 ceramic bracket의 전단결합강도는 임상적으로 사용하기에 충분한 값을 나타내었으며, resin bracket 경우 다른 bracket 비해 전단결합강도가 현저히 작은 값을 나타내었지만 임상적으로 사용이 가능한 값을 나타내었다. 2. Visible light를 이용한 metal bracket의 광중합시 광조사시간에 따른 전단결합강도는 광조사 시간에 따른 유의한 차이를 보이지 않았으며, 임상적으로 사용하기에 충분한 강도를 나타내었다. 3. Plasma arc light를 이용한 수종의 bracket 접착시 접착제 잔류지수를 통해 접착파절양상을 관찰한 결과, metal bracket과 resin bracket 경우 bracket기저면에 접착제가 반 이상 남아 있지 않은 경우가 많았으며, ceramic bracket의 경우 bracket기저면에 접착제가 반 이상 남아 있는 경우가 많았다. 4. Metal bracket의 부착시 plasma arc light를 2초간 광조사한 군과 visible light를 10초간 광조사한 군의 전단결합강도와 접착파절양상을 비교시 유의한 차이를 보이지 않았다. 6. Plasma arc light를 이용한 광중합시 광조사 거리에 따른 전단결합강도는 거리가 증가할수록 감소하였다. 이상의 실험 결과는 plasma arc light를 이용한 bracket의 접착시 전단결합강도 저하의 우려 없이 임상적으로 사용 가능함을 시사한다.

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