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플라즈마를 활용한 최근의 대기환경기술

  • Song, Yeong-Hun;Heo, Min;Lee, Dae-Hun;Gang, U-Seok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.119.2-119.2
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    • 2014
  • 대기환경 규제가 강화됨에 따라 기존 기술 대비 획기적인 성능과 가격 경쟁력을 갖춘 새로운 대기환경 기술에 대한 수요가 지속적으로 요구되고 있다. 특히 최근에는 종래의 분진, 이산화황가스 및 질소산화물에 대한 규제와 더불어 지구온난화가스인 이산화탄소, 과불화화합물 (Perfluorocompounds, PFCs), 메탄가스 등에 대한 규제가 강화되면서 이에 대응할 수 있는 대기환경 기술의 수요가 늘고 있다. 한국기계연구원에서는 지난 10 여 년간 지구온난화가스이자 난분해성 가스인 메탄 및 PFCs 가스를 플라즈마 화학반응 공정을 통해 분해하는 연구를 수행해왔으며, 이를 바탕으로 산업에 적용할 수 있는 기술개발도 병행하여 수행하였다. 현재 개발된 기술 가운데 일부는 산업에 실제로 적용되고 있으며, 이를 통해 산업현장에서는 지구온난화가스는 물론 질소산화물과 같은 다른 종류의 규제물질도 동시에 저감할 수 있었다. 본 발표에서는 플라즈마를 활용하여 난분해성 가스인 메탄과 PFCs를 분해하는 기술의 특성을 살펴보았으며, 이를 바탕으로 산업현장에 적용된 대기환경기술이 어떻게 활용되고 있는지를 소개하고 있다. 본 발표에서 다루게 될 플라즈마 발생기술은 펄스 코로나, 유전체장벽방전, 마이크로웨이브 토치, 아아크 토치 등이며, 플라즈마 발생조건은 수 torr 이하의 진공조건부터 및 대기압 조건에 이르고 있다.

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The Analysis of Trolley-Rail Short Circuit Current in a Single Track AT Feeding System (단선 AT 급전계통의 전차선-레일 단락 고장전류 분석)

  • Cho, Gyu-Jung;Ryu, Kyu-Sang;Lee, Hun-Do;Heo, Seung-Hun;Kim, Chul-Hwan;Kwon, Sung-Il;Kim, Cheol-Hwan
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.64 no.12
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    • pp.1659-1665
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    • 2015
  • In general, AT(Auto-transformer) is used to improve voltage sag and inductive interference in power lines and communication lines in AC electrical railway feeding system. Especially, Korean AT feeding system has different composition compared to other countries like Japan or France, so that it has some special characteristics. However, relays imported from other countries have been used in Korea, and settings of these relays should be modified and reflect distinct characteristics of Korean AT feeding system. Therefore, study about fault analysis based on modeled AT feeding system is important. In this paper, we modeled a single track AT feeding system by using PSCAD and analyzed fault current flow in case of trolley-rail short circuit fault. Finally, we presented current magnitude of each branch expressed by boosting current of AT.

Suppression of Diesel Emission Particle Extract-induced Micronuclei in Mouse Bone Marrow Cells by Pre-treatment with Ascorbic acid, ${\alpha}-Tocopherol$ or Glutathione

  • Heo, Moon-Young;Choi, Seong-Kyu;Yu, Ki-Seon;Kim, Hyun-Pyo;Sohn, Dong-Hun
    • Archives of Pharmacal Research
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    • v.12 no.2
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    • pp.94-98
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    • 1989
  • Induction of micronuclei by diesel emission particle extract (DEPE) in mouse bone marrow cells was suppressed by pre-treatment with ascorbic acid, ${\alpha}-tocopherol$ or glutathione (GSH). These compounds were given orally to mice at the dose of 1, 10 or 100 mg/kg/day for 5 consecutive days. The dose of DEPE (200 mg/kg) was administered intraperitoneally once to mice with the 5th administration of test compounds. Ascorbic acid, ${\alpha}-tocopherol$ and GSH all showed the dose-dependent suppression on DEPE-induced micronuclei.

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Design and Implementation of Personal Internet Broadcasting System Using Host Multicast scheme on FTTH Network Environment (FTTH망에서 호스트멀티캐스트를 이용한 개인 인터넷 방송 시스템 설계 및 구현)

  • Kim Kyoung-Tae;Son Seung-Chul;Heo Kwon;Lee Hyung-Ok;Kim Kyung-Hun;Nam Ji-Seung
    • Proceedings of the Korean Information Science Society Conference
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    • 2006.06d
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    • pp.157-159
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    • 2006
  • 본 논문에서는 FTTH 환경에 의해 가입자까지 100Mbps 이상의 대역폭을 보장하면서 실제 서비스 되어 질 수 있는 응용 시스템인 개인 인터넷 방송 시스템을 호스트 멀티캐스트 Scheme을 이용하여 설계 및 구현하였다. 전송 방식인 호스트 멀티캐스트에 대해 알아보고 개인 인터넷 방송 서버(Contents Provider)와 클라이언트(Host)의 구조에 효율적인 호스트 멀티캐스트 알고리즘인 Data Delivery Tree Algorithm(DDTA)를 제안하고, DDTA 알고리즘이 FTTH 환경에서 HDTV급 고화질 영상을 전송할 수 있는 개인 인터넷 방송 시스템에 효율적인 알고리즘이라는 것을 보인다.

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A study on the Life Cycle Cost reduction of the LRT's power systems based on the advanced Systems Engineering (시스템엔지니어링 기법 적용에 따른 경량전철 전기시스템의 생명주기비용 절감에 관한 연구)

  • Choi, Won-Chan;Bae, Joon-Ho;Heo, Jae-Hun;Joo, Ji-Young
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.1434-1439
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    • 2011
  • The purpose of this study is based on the optimize the system life cycle cost apply to the advanced systems engineering techniques consideration thought to the system life cycle for the power system which is the one of the major component of the light rail transit system. Generally, the systems engineering techniques apply to the LRT's power systems are not optimize the whole life cycle cost of the power systems because systems engineering management activities are concentrate in performing the key-technology oriented at the construction stage of the dedicated power systems for light rail transit. Through this study, All the stakeholders can be utilize a this advanced systems engineering techniques which is fully considered the life cycle cost through the considering in whole system life cycle (such as concept, design, operation, maintenance and dispose stage as well as construction stage) and adopted by KSX ISO/IEC 15288 system life cycle processes.

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Simulation Analysis of a Renewable Energy Based Microgrid using RTDS (RTDS를 이용한 신재생에너지 기반 마이크로그리드 시뮬레이션 해석)

  • Heo, Se-Rim;Kim, Gyeong-Hun;Lee, Hyo-Guen;Hwang, Chul-Sang;Park, Min-Won;Yu, In-Keun;Park, Jung-Do;Yi, Dong-Young;Lee, Sang-Jin
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.60 no.12
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    • pp.2190-2195
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    • 2011
  • Due to enhanced demands on quality, security and reliability of the electric power energy system, a microgrid has become a subject of special interest. In this paper, output characteristics of energy storage system (ESS) with an electric double layer capacitor (EDLC) and battery energy storage system (BESS) of a renewable energy based microgrid were analyzed under grid-connected and islanded operation modes. The microgrid which consists of photovoltaic and wind power turbine generators, diesel generator, ESS with an EDLC, BESS and loads was modeled using real time digital simulator. The results present the effective control patterns of the microgrid system.

The Effects of Being around Gambling and Gambling Advertising on Sports Gambling Addiction (주위도박과 도박광고가 스포츠도박중독에 미치는 영향)

  • Kim, Jeong-Eun;Heo, Jong-Hun;Ryu, Hwang-Gun
    • The Korean Journal of Health Service Management
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    • v.11 no.3
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    • pp.105-114
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    • 2017
  • Objectives : The purpose of this study was to investigate the effects of gambling environment factors (being around gambling, gambling ad access) and irrational gambling belief on the gambling behaviors of college students who experienced sports gambling. Methods : Study participants were 240 college students with sports gambling experience. Data were collected through self-report questionnaires and analyzed with SPSS 18.0. Results : Being around gambling and sports gambling ad access have a statistically significant effect on irrational gambling beliefs, which have statistically significant statistical effects on gambling addiction. Self-regulation did not show statistically significant regulatory effects between irrational gambling beliefs and gambling addiction. Conclusions : It is necessary to take a proactive approach to minimize the negative effects of sports betting and to be aware of the rapidly changing sports gambling environment factors.

Sn과 SnO 박막을 이용한 SnxSy 박막 합성

  • Kim, Tae-Hun;Kim, Jeong-Ju;Lee, Jun-Hyeong;Heo, Yeong-U
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.266.1-266.1
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    • 2016
  • 최근 태양전지에 대한 연구가 활발하기 이루어지고 있다. 그 중 본 연구에선 태양전지에 사용될 광흡수층에 대한 연구로 광흡수층은 광흡수계수와 밴드갭의 영향을 받고 SnS가 적합한 특성을 지니고 있다고 판단하여 이에 대한 합성과 특성에 대한 연구를 진행 하였다. SnxSy 박막은 Electrochemical deposition, Spray pyrolysis deposition, Furnace를 이용하는 등 다양한 방법이 있다. 이러한 방법들은 대부분 막질이 좋지 않다고 알려져 있는데 그 중 Furnace를 이용하는 방법은 간단하며 넓은 면적에 쉽게 증착이 가능하다는 장점이 있지만 S의 양과 온도에 민감하다. 본 연구에서는 Sn과 SnO 박막을 전구체로 사용하였으며 S의 양과 온도를 조절하여 로를 이용하여 합성하였다. 이에 대한 조성 및 구조적 특성을 분석하기 위해 XRD를 전기적 특성을 확인하기 위하여 Hall effect measurement를 통하여 측정하였다.

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Study of Carbon Nanotubes Properties by Post-treatment Conditions (후처리 조건에 따른 탄소나노튜브 특성의 변화)

  • Choi Sung-Hun;Lee Jae-Hyeong;Yang Jong-Seok;Park Dae-Hee;Heo Jeong-Ku
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.19 no.10
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    • pp.930-934
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    • 2006
  • This paper reports a change of carbon nanotubes(CNTs) properties by post-treatment process after growth of CNTs. CNTs were treated by thermal method and solution method, and then investigated in detail using field emission scanning electron microscopy(FE-SEM), high resolution transmission scanning electron microscopy(HR-TEM), RAMAN spectroscopy, and Fourier Transform Infrared Spectrometer (FT-IR). FT-IR spectra showed that the amount of hydroxyl generated on surface of CNTs were changed with post-treatment condition. FE-SEM and TEM images were shown CNTs diameter and density variations were dependent with their treatment conditions. RAMAN spectroscopy was shown that carbon nanotubes structure vary with treatment conditions.

IGBT Modeling and Inverter System Simulation (IGBT의 모델링과 인버터 시스템 시뮬레이션)

  • Seo, Young-Soo;Baek, Dong-Hyun;Cho, Moon-Taek;Heo, Jong-Myung;Lee, Sang-Hun
    • Proceedings of the KIEE Conference
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    • 1996.07a
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    • pp.464-466
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    • 1996
  • IGBT devices have the best features of both power MOSFETs and power bipolar transistors, i.e., efficient voltage gate drive requirements and high current density capability. When designing circuit and systems that utilize IGSTs or other power semiconductor devices, circuit simulations are needed to examine how the devices affect the behavior of the circuit. The IGBT model in this paper is verified by comparing the results of the model with experimented results for various circuit operating conditions. The model performs well and describes experimented results accurately for the range of static and dynamic condition in which the device is intended to be operated.

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