• Title/Summary/Keyword: Halogen

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Lifetime Estimation of an Automotive Halogen Lamp (자동차용 Halogen Lamp 의 수명 예측)

  • Kim, Chung-Sik;Shin, Seung-Jung;Kwack, Kae-Da
    • Proceedings of the KSME Conference
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    • 2008.11a
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    • pp.1259-1264
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    • 2008
  • This paper presents an accelerated life test for burn out of tungsten filament of automotive halogen lamp. There are many failure modes and failure factors that associated with tungsten filament. But in this explain the dominant failure mode of tungsten filament is the bumout of the filament failure. At first, over voltage, high temperature, inrush current and vibration are selected as stress factors by using of two stage Quality Function Deploymeng(QFD). And we planed accelerated life test that has one factor(voltage) and three levels. By experiment it has absorbed that over voltage has an effect on the life of halogen lamp. Using ALTA programs, we estimated the common shpae parament of Weibull distribution, life-stress relationship and $B_{100p}$ life.

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Two-dimensional Supramolecular Ordering via Hydrogen and Halogen Bondings

  • Yoon, Jong-Keon;Kim, Ho-Won;Jeon, Jeong-Heum;Kahng, Se-Jong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.11-11
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    • 2010
  • Supramolecualr ordering has been actively studied due to it's possible applications to the fabrication processes of nano-electronic devices. Van der Waals interaction and hydrogen bonding are frequently studied mechanisms for various molecular structures based on non-uniform charge distributions. Halogen atoms in molecules can have electrostatic interactions with similar strength. Big halogen atoms have strong non-uniform charge distributions. To study molecular orderings formed by hydrogen and halogen interactions, we chose a molecular system containing oxygen, hydrogen, and bromine atoms, a bromo-quinone. A two-dimensional molecular network was studied on Au(111) using a low-temperature scanning tunneling microscope. Bromo-quinonemolecules form self-assembled square grids having windmill structures. Their molecular orderings, chiral structures, and defects are explained in terms of hydrogen and halogen interactions.

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Two-dimensional Supramolecular Structures by Hydrogen and Halogen Interactions

  • Yoon, Jong-Keon;Kim, Ho-Won;Chung, Kyung-Hoon;Kahng, Se-Jong
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.354-354
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    • 2010
  • Supramolecualr ordering has been actively studied due to it's possible applications to the fabrication processes of nano-electronic devices. Van der Waals interaction and hydrogen bonding are frequently studied mechanisms for various molecular structures based on non-uniform charge distributions. Halogen atoms in molecules can have electrostatic interactions with similar strength. Big halogen atoms have strong non-uniform charge distributions. To study molecular orderings formed by hydrogen and halogen interactions, we chose a molecular system containing oxygen, hydrogen, and bromine atoms, a bromo-quinone. A two-dimensional molecular network was studied on Au(111) using a low-temperature scanning tunneling microscope. Bromo-quinone molecules form self-assembled square grids having windmill structures. Their molecular orderings, chiral structures, and defects are explained in terms of hydrogen and halogen interactions.

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Wear Of Resin Composites Polymerized By Conventional Halogen Light Curing And Light Emitting Diodes Curing Units (HALOGEN LIGHT CURING UNIT 과 LIGHT EMITTING DIODES CURING UNIT 을 이용하여 중합되어진 복합레진의 마모 특성 비교)

  • 이권용;김환;박성호;정일영;전승범
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2004.10a
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    • pp.1057-1060
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    • 2004
  • In this study, the wear characteristics of five different dental composite resins cured by conventional halogen light and LED light sources were investigated. Five different dental composite resins of Surefil, Z100, Dyract AP, Fuji II LC and Compoglass were worn against a zirconia ceramic ball using a pin-on-disk type wear tester with 15 N contact force in a reciprocal sliding motion with sliding distance of 10 mm/cycle at 1Hz under the room temperature dry condition. The wear variations of dental composite resins were linearly increased as the number of cycles increased. It was observed that the wear resistances of these specimens were in the order of Dyract AP > Surefil > Compoglass > Z100 > Fuji II LC. On the morphological observations by SEM, the large crack formation on the sliding track of Fuji II LC specimen was the greatest among all resin composites. Dyract AP showed the least wear with few surface damage. There is no significant difference in wear performance between conventional halogen light curing and light emitting diodes curing sources. It indicates that a light emitting diodes (LED) source can replace a halogen light source as a curing unit for composite resin restorations.

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The Effect of Erythrosine-mediated Photodynamic Therapy on Intraorally Formed Biofilm on Titanium Surface

  • Park, Se-Hwan;Lee, Si-Young;Chang, Beom-Seok;Um, Heung-Sik;Lee, Jae-Kwan
    • International Journal of Oral Biology
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    • v.37 no.3
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    • pp.103-108
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    • 2012
  • The purpose of this study was to assess the efficacy of photodynamic therapy (PDT) using erythrosine and a halogen light source to treat a biofilm formed on a machined surface titanium disk in vivo. Ten volunteers carried an acrylic appliance containing six machined surface titanium disks on the upper jaw over a period of five days. After the five days of biofilm formation period, the disks were removed. PDT using 20 ${\mu}M$ erythrosine and halogen light was then applied to the biofilms formed on the disks. Experimental samples were divided into a negative control group (no erythrosine and no irradiation), E0 group (erythrosine 60s + no irradiation), E30 group (erythrosine 60s + halogen light 30s), and E60 group (erythrosine 60s + halogen light 60s). Following PDT, the bacteria in the biofilm were found to be detached from each disk. Each suspension with detached bacteria were diluted and cultivated on a blood-agar plate for five days under anaerobic conditions. The cultivated bacterial counts in the E60 group were significantly lower than the control group (86.4%) or E0 group (76.7%). In the experimental groups also, the light exposure time and bacterial counts showed a negative correlation. In conclusion, PDT using erythrosine and halogen light has bactericidal effects on biofilms formed on a titanium disk in vivo. Notably, applying 20 ${\mu}M$ erythrosine and 60 seconds of halogen light irradiation had a significantly potent effect.

A Study on Accelerated Life Test of Halogen Lamps for Medical Device (의료용 할로겐램프의 가속수명시험에 관한 연구)

  • Jung, Jae Han;Kim, Myung Soo;Lim, Heonsang;Kim, Yong Soo
    • Journal of Korean Society for Quality Management
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    • v.41 no.4
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    • pp.659-672
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    • 2013
  • Purpose: The purpose of this study was to estimate life time of halogen lamps and acceleration factors using accelerated life test. Methods: Voltage was selected as an accelerating variable through the technical review about failure mechanism. The test was performed at 14.5V, 15.5V and 16.5 for 4,471 hours. It was assumed that the lifetime of Halogen lamps follow Weibull distribution and the inverse power life-stress relationship models. Results: Mean lifetimes of pin and screw types were 19,477 hours and 6,056 hours, respectively. In addition, acceleration factor of two items are calculated as 4.8 and 2.2 based on 15.5V, respectively. Conclusion: The life-stress relationship, acceleration factor, and MTTF at design condition are estimated by analyzing the accelerated life test data. These results suggest that voltage was very important factor to accelerate life time in the case of halogen lamps and the life time of pin type is three times longer than screw type lamps.

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

  • Choi, Sok-Jin
    • 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.

Transmitting Ability of Halogen Light in Different Composite Resin Colors (복합레진 색상에 따른 Halogen light의 투과도)

  • Cho, Kyung-Mo
    • Journal of Dental Rehabilitation and Applied Science
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    • v.26 no.4
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    • pp.447-453
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    • 2010
  • The purpose of this study was to compare the light transmitting ability of halogen light in different colors and thicknesses. A1, A2, A3 colors of Z-250 composite resin(3M ESPE, St. Paul, U.S.A.) were used. Degree of conversion of separated resin specimens under the 2, 3, 4mm thickness resin were measured by FTIR spectroscopy. The result shows that decrease of degree of conversion by increase of resin thickness and decrease of degree of conversion by decrease of lightness of color. Within the limitation of results, it is recommended to use more light color of composite resin in small thickness to improve degree of conversion when use halogen light.

An Experimental Study on the Lens Surface Temperature Distribution of P/C Headlamp Using the Three Category of H4 Halogen Bulbs (PIC 렌즈 전조등 렌즈면의 온도분포에 관한 실험적 연구)

  • 박경석;강병도
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.4
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    • pp.158-165
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    • 2002
  • This Paper deals with the headlamp lens surface temperature distribution of p/c headlamp using the three categories of H4 halogen bulbs. Glass is gradually replaced by P/C for the lens material off vehicle headlamp due to the weight reduction and stream lined body of a vehicle. With this trend, the newly established standards for a headlamp with a P/C lens in Europe requires that the heat generated by a bulb should not distort the lens surface. Also the requirements fur the bulb of a headlamp are being enforced in U.S.A & Europe. However, such requirements are not established yet in Korea. By using three kinds (60/55w, 100/90w, 130/90w) of H4 halogen bulbs in this experiment, the surface temperature distribution and Max. temperature on the lens were measured. The results of this study implies the necessity of requirement fur the bulb off headlamp.

Wear of Resin Composites Polymerized by Conventional Halogen Light Curing and Light Emitting Diodes Curing Units (Halogen Light Curing Unit과 Light Emitting Diodes Curing Unit을 이용하여 중합되어진 복합레진의 마멸 특성 비교)

  • Lee Kwon-Yong;Kim Hwan;Park Sung-Ho;Jung Il-Young;Jeon Seung-Beom
    • Tribology and Lubricants
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    • v.21 no.6
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    • pp.268-271
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    • 2005
  • In this study, the wear characteristics of five different dental composite resins cured by conventional halogen light and LED light sources were investigated. Five different dental composite resins of Surefil, Z100, Dyract AP, Fuji II LC and Compoglass were worn against a zirconia ceramic ball using a pin-on-disk type wear tester with 15N contact force in a reciprocal sliding motion of sliding distance of 10mm/cycle at 1Hz under the room temperature dry condition. The wear variations of dental composite resins were linearly increased as the number of cycles increased. It was observed that the wear resistances of these specimens were in the order of Dyract AP > Surefil > Compoglass > Z100 > Fuji II LC. On the morphological observations by SEM, the large crack formation on the sliding track of Fuji II LC specimen was the greatest among all resin composites. Dyract AP showed less wear with few surface damage. There is no significant difference in wear performance between conventional halogen light curing and light emitting diodes curing sources. It indicates that a light emitting diodes (LED) source can replace a halogen light source as curing unit for composite resin restorations.