• Title/Summary/Keyword: harmful material

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Electric-optical Characteristics of Backlight Unit with LED Light Source in Low Temperature Condition

  • Han, Jeong-Min;Seo, Dae-Shik
    • Transactions on Electrical and Electronic Materials
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    • 제8권2호
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    • pp.93-96
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    • 2007
  • LCD (liquid crystal display) industry is needed to goods of high reliability and is interested in products without harmful material. In this experiment, we made the LED backlight unit for Automotive-navigation. And for making this backlight unit we used to eight side emitting type white LEDs with 1 W high power of the lumileds company. We could know that this backlight unit releases to 6500 nit in 14 W power consumption and start up voltage time is under the 15ms in the ambient temperature $-20\;^{\circ}C$.

점토 결합 SiC 소결체의 마찰 마모 특성 (Tribological Properties of Clay Bonded SiC)

  • 한상준;이경희;이재한;김홍기
    • 한국세라믹학회지
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    • 제32권9호
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    • pp.1027-1032
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    • 1995
  • SiC had been widely applied for mechanical sealing as a sealing material. SiC sintering is commonly made of reaction sintering, presureless sintering, and hot isostatic pressing (HIP) sintering. In this investigation, however, clay bonded sintering was used to avoide any complications of the special sintering methods as mentioned above. In order to prevent harmful SiC oxidation in the clay bonded sintering, clay and frit were used to form the SiC oxidation protecting layer and graphite was added to provide high solid lubricity. As a result, the material with 6% clay (clay 5.4% and frit 0.6%) and 2~4% graphite (45 mesh) sintered at 140$0^{\circ}C$ for 3 hours, showed the following physical properties; porosity 6%, static friction coefficient 0.15, kinematic coefficient 0.1,. and specific wear rate 4.8$\times$10-8 $\textrm{mm}^2$kgf-1. On the other hand, the flexural strength was 900kgf/$\textrm{cm}^2$. This tribological characteristic properties were similar to those of the reaction sintered SiC except the flexural strength.

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세라믹스의 축열연소시스템 응용 (Ceramic Application for Regenerative Burner System)

  • 한동빈;박병학;김영우;배원수
    • 한국세라믹학회지
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    • 제36권5호
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    • pp.497-503
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    • 1999
  • Recently regenerative burner system was developed and begins to be gradually used for better energy savings. Compared to conventional burner system the regenrative one has the several merits such as higher fuel efficiency light weigh of apparatus low harmful toxic gas and homogeneous heating zone etc. The regenerative material a very important component of the new regenerative burner system should possess the properties of low specific density higher surface area and high specific heat capacity. Ceramics is the best regenerative material because of stable mechanical properties even at high temperature and better thermal properties and excellent chemical stability. In this study alumina ball alumina tube 3-D ceramic foam and hoeycomb as regenerative materials were tested and evaluated. The computer silumation was conducted and compared to the result of field test. This paper is aimed to introduce a new application of ceramics at high temperature.

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고전압트랜스포머의 진공이 방사선출력 노이즈에 미치는 영향 (Electric power characteristic test of diagnostic X-ray high voltage transformer by input power condition)

  • 김영표;천민우;박용필
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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    • pp.499-499
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    • 2008
  • High voltage transformer of Diagnostic X-ray system has been contributed to wiping out disease to get a good quality images from patients. High voltage transformer of diagnostic X-ray system has been usefully used for diagnostic purpose but if high voltage transformer performances are deteriorated, low quality image will be archived. In this case, operator has to exposure to get a more good quality images. In this case, unexpected radiation could be exposed to patient and it is very harmful to the patient. And I would like to design and make equipment to checkable high voltage transformer performance after that I wish to test and study what it is most influences in radiation output quality.

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산화마그네슘 기반 규조토를 활용한 흡착형 경화체의 물리적 특성 (Physical Properties of Magnesium Oxide-Based Adsorption Matrix using Diatomite)

  • 이원규;경인수;이상수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2019년도 춘계 학술논문 발표대회
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    • pp.184-185
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    • 2019
  • Korea has defined fine dust as a social disaster as the problem of fine dust and air pollution becomes serious. Fine dust is classified as class one carcinogens because it is harmful to human body. When fine dusts enter the human body, they cause bronchial and skin diseases such as respiratory allergies, irritable pneumonia, asthma and atopy. As the air pollution becomes serious, the government is demanding measures to reduce fine dust. The polluted air in the outdoor is introduced into the room, thereby increasing the pollution degree of the indoor air quality. In this study, an adsorption type matrix for the improvement of indoor air quality was produced. Magnesium oxide and magnesium chloride were used as binders and diatomaceous earth was used as a adsorption material.

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천연항균물질을 이용한 항균모르타르의 개발에 관한 기초적 연구 (A fundamental study on development of antifungus mortar using natural antimicrobial materials)

  • 이민수;장홍석;소형석;소승영
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2013년도 추계 학술논문 발표대회
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    • pp.52-53
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    • 2013
  • According to the increases the standard of living of the people, requirements for building environments are also being diversified. The fungus that occurred the building is not good the health of occupants as well as undermine the value of the building. However, chemical antimicrobial agent contain ingredients harmful to human body and it has an impact on indoor air quality. Therefore, the use of natural antimicrobial material is strongly required. In this study, the fungal reproductive inhibit capacity was evaluated by using mortars with natural antimicrobial material.

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전기접점용 Ag-CdO합금의 물성에 미치는 Mm(misch metal) 첨가의 영향 (Effects of Mm(misch metal) Addition on The Property of Ag-CdO alloys for Electrical Contactor)

  • 박수동;이희웅;김봉서;김병걸;송재영
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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    • pp.34-37
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    • 2004
  • It is well known that Ag-CdO alloy for electrical contactor has been widely used in weak or middle electric current field. But it is necessary to decrease Cd contents without decrease of contactor property because Cd is harmful to human body. The present work has been carried out to investigate effects of Mm (misch metal) addition on the property of Ag-CdO alloy for electrical contactor. As the results of present works, hardness and strength was improved and arc resistance was improved, also, in spite of decrease Cd contents by the Mm addition. It was estimated that Ag-oxide particle was refined by Mm addition.

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유해 세균 제거 분석 연구 (A study on Harmful Bacillus Removal Analysis)

  • 조국희;김영배;조문수;박보현;신광철;이동훈
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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    • pp.38-42
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    • 2004
  • In this research, we used discharge tube without dielectric bead or with dielectric beads($SiO_2$, $Al_2O_3$, or $ZrO_2$), and discharge in water for removal of Escherichia coli. At the result of experiments, the removal characteristics of Escherichia coli appeared relation ratio to input voltage. Because, the electric field of discharge tube is increased when input voltage is increased. And, discharge tube used dielectric bead($ZrO_2$), the removal characteristics of Escherichia coli was better than cases of else.

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리튬 배터리 퓨즈 온도 보상에 따른 과전류 시퀀스 제어 알고리즘 설계 (Design of Over Current Sequence Control Algorithm According to Lithium Battery Fuse Temperature Compensation)

  • 송정용;허창수
    • 한국전기전자재료학회논문지
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    • 제32권1호
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    • pp.58-63
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    • 2019
  • Lithium-ion batteries used for IT, automobiles, and industrial energy-storage devices have battery management systems (BMS) to protect the battery from abnormal voltage, current, and temperature environments, as well as safety devices like, current interruption device (CID), fuse, and vent to obtain positive temperature coefficient (PTC). Nonetheless, there are harmful to human health and property and damage the brand image of the manufacturer because of smoke, fire, and explosion of lithium battery packs. In this paper, we propose a systematic protection algorithm combining battery temperature, over-current, and interconnection between protection elements to prevent copper deposition, internal short circuit, and separator shrinkage due to frequent and instantaneous over-current discharges. The parameters of the proposed algorithm are suggested to utilize the experimental data in consideration of battery pack operating conditions and malicious conditions.

쌀벌레 방제를 위한 포장소재의 개발 (Development of Packaging Materials for Prevention and Extermination of Rice Weevils)

  • 이지영;김철환;이경선;이지영;조후승;임수진;신정용;조인준;남혜경
    • 펄프종이기술
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    • 제45권2호
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    • pp.41-45
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    • 2013
  • Extractives of garlic (Allium scorodorpasum) and green pepper (Capsicum annuum L.) were used to prevent and exterminate rice weevils which contaminate stored rice. The extractives exhibited great efficacy against Sitophilus oryzae and Tribolium castaneum by annihilating all the weevils contained in a bottle. Furthermore, kraft paper coated by 5% extractives also displayed good effectiveness against the rice weevils. When rice weevils were stored with rice in a sack made of extractives-coated kraft paper, the number of living insects was sharply decreased according to elapsed time. In particular, 1,4-benzoquinone, which is very harmful to human, was detected from rice contaminated by Sitophilus oryzae and Tribolium castaneum through the analysis of GC/MS.