• Title/Summary/Keyword: 석기용

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A study on the hazard of electric shock for 220V domestic receptacles (220V 가정용 콘센트에 대한 감전위험성 연구)

  • 한기붕;정세중;이대종
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.671-674
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    • 2000
  • A children's electric shock accidents have broken out because children can easily insert sharp things in 220V receptacle holes. As the test result of pushing force, children's pushing force was about 2-4kg and the pushing force of sharp things was less than 2kg. Therefore, it is reason for electric shock that children's pushing force is large than pushing force of sharp things. We have measured insulation resistance for the receptacles of five companies during 50 weeks in humid condition. As these results, Insulation resistance for the receptacles of J. Co. had rapidly decreased with lapse of time. As the result for investigating the surface of receptacle by SEM and EDX, Al, Fe and Br, which weren't discovered at original form, were produced. Therefore, the receptacles of J. Co. should be the improved in the quality of insulating material because insulation resistance can be decreased in humid environment

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Development of Simulator for High-Speed Elevator System (고속 엘리베이터 시스템용 시뮬레이터 개발)

  • Ryu, Hyeong-Min;Kim, Seong-Jun;Seol, Seung-Gi;Gwon, Tae-Seok;Kim, Gi-Su;Sim, Yeong-Seok;Seok, Gi-Ryong
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.51 no.2
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    • pp.77-82
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    • 2002
  • This Paper describes the dynamic load simulator for high-speed elevator system, which can emulate 3-mass system as well as equivalent 1-mass system. In order to implement the equivalent inertia of entire elevator system the conventional simulators have generally utilized the mechanical inertia(flywheel) with large radius, which makes the entire system large and heavy. In addition, the mechanical inertia should be replaced each time in order to est another elevator system. In this paper, the dynamic load simulation methods using electrical inertia are Presented so hat the volume and weight of simulator system are greatly reduced and the adjustment of inertia value can be achieved easily by software. Experimental results show the feasibility of this simulator system.

The measurement equipment for 915MHz 30kW class magnetron test (915MHz 30kW 마그네트론 시험을 위한 측정 장비)

  • Cho, Kook-Hee;Jeon, Seok-Gy;Jung, Sun-Shin;Lee, Hong-Sik
    • Proceedings of the KIEE Conference
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    • 2006.07c
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    • pp.1570-1571
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    • 2006
  • 산업용 가열, 건조, 해동 기술 분야에서 피 가열물의 열전달 특성이 좋지 않은 경우 대출력 마그네트론을 적용하여 전자파 가열방식을 이용함으로써 기존의 가열방식 보다 효율을 상당히 개선할 수 있음은 오래 전부터 알려져 왔다. 그러나 국내에서는 대출력(30kW급 이상) 마그네트론 제조기술 및 성능분석을 할 수 없어 외국에서 수입하여 산업에 산발적으로 적용하고 있는 실정이다. 따라서 본 연구는 30 kW급 대출력 마그네트론과 구동전원을 위한 시험 장비를 구축하여 신뢰성을 확보하면 마그네트론을 이용한 고효율 가열, 건조, 해동 기술에 적용이 가능하다.

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Q measurement of two port RE cavity by scattering parameters (산란행렬에 의한 2단자망 RF 공동공진기의 Q 측정)

  • 한대현
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.4 no.4
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    • pp.895-899
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    • 2000
  • A method of measuring Q of a two port cavity by scattering parameters is proposed. The scattering parameters of a two port cavity resonator are derived by a lumped equivalent circuit model as a function of cavity parameters, including the cavity Q. These can be also obtained by direct measurement with a modern network analyzer, The results show good agreement with those from other well-known methods. This two port measurement can provide additional information such as the coupled power ratio, which is one of the important parameters for the beam accelerating cavities.

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The Effects of Zeolite-Type Catalysts on the Pyrolysis Reaction of Raw Material Resin to Produce Fuel-Oil from Waste Vinyl (폐 농업용 비닐 수지에서 연료유 생성을 위한 원료 수지의 열분해 반응에서 제올라이트계 촉매의 영향)

  • Bak, Young-Cheol;Choi, Joo-Hong;Cho, Tae-Ho
    • Korean Chemical Engineering Research
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    • v.47 no.3
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    • pp.303-309
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    • 2009
  • The effects of zeolite type catalysts addition on the thermal decomposition of low density polyethylene(LDPE) and ethylene vinyl acetate(EVA) resin have been studied in a thermal analyzer(TGA, DSC) and a small batch reactor. The zeolite type catalysts tested were natural zeolite, FCC catalyst, used FCC catalyst, and catalyst A. As the results of TGA experiments, addition of antifogging-agent decreased the pyrolysis point to $250^{\circ}C$, but addition of longevity-agent and clay reduced the pyrolysis rate in EVA resin. Addition of the zeolite type catalysts in the LDPE resin increased the pyrolysis rate in the order of catalyst A > used FCC catalyst > natural zeolite > LDPE resin. Addition of the zeolite type catalysts in the EVA resin increased the pyrolysis rate in the order of used FCC catalyst > natural zeolite > catalyst A > EVA resin. In the DSC experiments for LDPE resin, addition of zeolite type catalysts decreased the melting point and the heat of pyrolysis reaction in the order of catalyst A > used FCC catalyst > natural zeolite> LDPE resin. In the batch system experiments, the mixing of natural zeolite enhanced the yield of liquid fuel oil.

An Efficient Hardware Implementation of AES-based CCM Protocol for IEEE 802.11i Wireless LAN Security (IEEE 802.11i 보안용 AES 기반 CCM 프로토콜의 효율적인 하드웨어로 구현)

  • Hwang, Seok-Ki;Lee, Jin-Woo;Kim, Chay-Hyeun;Song, You-Su;Shin, Kyung-Wook
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.591-594
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    • 2005
  • This paper describes a design of AES-based CCM Protocol for IEEE 802.11i Wireless LAN Security. The CCMP core is designed with 128-bit data path and iterative structyre which uses 1 clock cycle per round operation. To maximize its performance, two AES cores are used, one is for counter mode for data confidentiality and the other is for CBC(Cipher Block Chaining) mode for authentication and data integrity. The S-box that requires the largest hardware in AES core is implemented using composite field arithmetic, and the gate count is reduced by about 23% compared with conventional LUT-based design. The CCMP core designed in Verilog-HDL has 35,013 gates, and the estimated throughput is about 768Mbps at 66-MHz clock frequency.

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On-line Monitoring of Glucose and Acetate by Flow-Injection Analysis in Escherichia coli Fermentation Process (대장균 발효공정에서 흐름주입분석을 이용한 글루코스와 초산의 온라인 모니터링)

  • 이종일
    • KSBB Journal
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    • v.13 no.3
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    • pp.244-250
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    • 1998
  • Flow-injection analysis (FIA) for on-line monitoring of glucose and acetate are described and employed in E.coli fermentation process. Glucose oxidase (GOD) for the detection of glucose is immobilized on epoxy polymer support, which is packed in a small cartirdge, and applied to a GOD-FIA system. The detection of acetate is based on the inhibition of acetate to the oxidation of sarcosine by sarcosine oxidase (SOD). SOD is also immobilized on epoxy polymer support and used for a SOD-FIA system. GOD-FIA system is characterized as well as SOD-FIA system by the investigation of the effects of pH, temperature and metabolites in samples on the peak height. GOD-FIA and SOD-FIA systems were also applied for on-line On-line measurements buy FIA measurements by FIA were in god agreement with off-line measurements.

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Cation Ordering and Microwave Dielectric Properties of Complex Perovskite Compounds $La(Mg_{1/2}Ti_{1/2})O_3$ and $La(Mg_{1/2}Zr){1/2})O_3$ ($La(Mg_{1/2}Ti_{1/2})O_3$$La(Mg_{1/2}Zr){1/2})O_3$에서의 양이온 규칙과 고주파 유전특성)

  • 조서용;고경현;홍국선;박순자
    • Journal of the Korean Ceramic Society
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    • v.34 no.3
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    • pp.330-336
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    • 1997
  • 1:1 복합 페로스카이트 물질인 La(Mg1/2Ti1/2)O3 and La(Mg1/2Zr1/2)O3의 양이온 규칙 존재와 고주파 유전특성을 x선 회절과 회로망분석기를 사용하여 조사하였다. 기존의 연구에서는 두 물질 모두 양이온 규칙이 없으며 입방정 구조를 갖는다고 보고되었지만, 본 연구에서의 x선 분석에서는 양이온 규칙을 나타내는 초격자회절선과 비입방정 구조를 의미하는 기본회절선의 split이 발견되었다. 고주파 영역에서의 유전율은 La(Mg1/2Ti1/2)O3의 경우 29,La(Mg1/2Zr1/2)O3는 24, 품질계수(Q*f)는 각각 73000, 49000이다. 공진주파수 온도계수는 La(Mg1/2Ti1/2)O3의 경우 - 65ppm/$^{\circ}$C,La(Mg1/2Zr1/2)O3는 -80ppm/$^{\circ}$C로 음의 값을 가진다.

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