• Title, Summary, Keyword: TCO

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Performance Design of TCO System of the Solid Rocket Motor (고체 로켓모터의 TCO 성능 설계)

  • Hwang Yong-Seok;Yoon Myong-Won;Oh Jong-Yun;Bae Joo-Chan
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • pp.53-56
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    • 2006
  • This paper describes performance design of a solid rocket motor on which thrust cut-off system is installed, and evaluates performance of a rocket motor according to a size of TCO ports. TCO system installed on motors was made to carry out firing tests, and the trend of thrust due to various sizes of TCO port was analyzed to find the existence of the port size for maximum reversal thrust. Conservation equations were used to design performance of motors and to analyze test results. This technique for performance design will be usefully applied to the design of similar TCO systems.

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Performance Design of TCO System of the Solid Rocket Motor (고체 로켓모터의 TCO 성능 설계)

  • Hwang, Yong-Seok;Yun, Myeong-Won;O, Jong-Yun;Bae, Ju-Chan
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.34 no.5
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    • pp.101-106
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    • 2006
  • This paper describes performance design of a solid rocket motor on which thrust cut-off system is installed, and evaluates performance of a rocket motor according to a size of TCO ports. TCO system installed on motors was made to carry out firing tests, and the trend of thrust due to various sizes of TCO port was analyzed to find the existence of the port size for maximum reversal thrust. Conservation equations were used to design performance of motors and to analyze test results. This technique for performance design will be usefully applied to the design of similar TCO systems.

Out Gassing from Plastic Substrates Affect on the Electrical Properties of TCO Films (플라스틱 기판의 Outgassing이 TCO 박막의 전기적 특성에 미치는 영향)

  • Kim, Hwa-Min;Ji, Seung-Hun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.22 no.11
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    • pp.961-968
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    • 2009
  • In this work, transparent conductive oxide(TCO) films such as $In_2O_3-SnO_2$(ITO) and $In_2O_3-ZnO$(IZO) were prepared on polyethylene naphthalene(PEN) and glass substrates by using rf-magnetron sputtering system. The TCO films deposited on PEN substrate show very poor conductivity as compared to that of the TCO films deposited on glass substrates. From the results of the residual gas analysis(RGA) test, this poor stability of plastic substrate is presumed to be caused by the deteriorated adhesion between the TCO films and the plastic substrate due to outgassing from the plastic substrate during deposition of TCO films. From our experiment, it is found that the vaporization of some defects in the plastic substrates deteriorate the adhesion of the TCO films to the plastic substrate, because the most plastic substrates containing the water vapor and/or other adsorbed particles such as organic solvents. Mixing of these gases vaporized in the sputtering process will also affect the electrical property of the deposited TCO films. Inorganic thin composite $(SiO_2)_{40}(ZnO)_{60}$ film as a gas barrier layer is coated on the PEN substrate to protecting the diffusion of vapors from the substrate, so that the TCO films with an improved quality can be obtained.

Synthesis of TCO-less Solar Cell using Metal Mesh Type Electrode and its Photovoltaic Characteristics (금속 메쉬 전극을 이용한 TCO-less 광전변환소자 제작 및 광전변환 특성)

  • Park, Min-Woo;Sung, Youl-Moon
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.25 no.2
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    • pp.126-130
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    • 2011
  • Transparent conductive oxide (TCO) is an important part in the construction of dye-sensitized solar cells (DSCs) because of its low sheet resistance, sufficient light transparent ability and high photoelectrical response as a porous photo-electrode material of DSCs. However, the use of TCO for the two DSC electrodes can result in significant cost increase for the less effective DSCs compared to Si based solar cell. Therefore, the replacement of TCO is required for the commercial production of DSCs. In this study, TCO electrodes are replaced by stainless steel mesh. The 3.44[%] efficiency of the prepared TCO-less DSCs sample was obtained.

Doping-free Transparent Conducting Schottky Type Heterojunction Solar Cells

  • Kim, Joon-Dong
    • Proceedings of the Korean Vacuum Society Conference
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    • pp.209-209
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    • 2012
  • High-efficient transparent conductive oxide (TCO) film-embedding Si heterojunction solar cells were fabricated. An additional doping was not applied for heterojunction solar cells due to the spontaneous junction formation between TCO films and an n-type Si substrate. Three different TCO coatings were formed by sputtering method for an Al-doped ZnO (AZO) film, an indium-tin-oxide (ITO) film and double stacks of ITO/AZO films. An improved crystalline ITO film was grown on an AZO template upon hetero-epitaxial growth. This double TCO films-embedding Si heterojunction solar cell provided significantly enhanced efficiency of 9.23% as compared to the single TCO/Si devices. The effective arrangement of TCO films (ITO/AZO) provides benefits of a lower front contact resistance and a smaller band offset to Si leading enhanced photovoltaic performances. This demonstrates a potential scheme of the effective TCO film-embedding heterojunction Si solar cells.

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Metal Oxide-Based Heterojunction Broadband Photodetector (산화물 반도체 기반의 이종접합 광 검출기)

  • Lee, Sang-eun;Lee, Gyeong-Nam;Ye, Sang-cheol;Lee, Sung-ho;Kim, Joondong
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.31 no.3
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    • pp.165-170
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    • 2018
  • In this study, double-layered TCO (transparent conductive oxide) films were produced by depositing two distinct TCO materials: $SnO_2$ works as an n-type layer and ITO (indium-doped tin oxide) serves as a transparent conductor. Both transparent conductive oxide-films were sequentially deposited by sputtering. The electrical and optical properties of single-layered TCO films ($SnO_2$) and double-layered TCO ($ITO/SnO_2$) films were investigated. A TCO-embedding photodetector was realized through the formation of an $ITO/SnO_2/p-Si/Al$ layered structure. The remarkably high rectifying ratio of 400.64 was achieved with the double-layered TCO device, compared to 1.72 with the single-layered TCO device. This result was attributed to the enhanced electrical properties of the double-layered TCO device. With respect to the photoresponses, the photocurrent of the double-layered TCO photodetector was significantly improved: 1,500% of that of the single-layered TCO device. This study suggests that, due to the electrical and optical benefits, double-layered TCO films are effective for enhancing the photoresponses of TCO photodetectors. This provides a useful approach for the design of photoelectric devices, including solar cells and photosensors.

A Study on Aviation Safety and Third Country Operator of EU Regulation in light of the Convention on international Civil Aviation (시카고협약체계에서의 EU의 항공법규체계 연구 - TCO 규정을 중심으로 -)

  • Lee, Koo-Hee
    • The Korean Journal of Air & Space Law and Policy
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    • v.29 no.1
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    • pp.67-95
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    • 2014
  • Some Contracting States of the Chicago Convention issue FAOC(Foreign Air Operator Certificate) and conduct various safety assessments for the safety of the foreign operators which operate to their state. These FAOC and safety audits on the foreign operators are being expanded to other parts of the world. While this trend is the strengthening measure of aviation safety resulting in the reduction of aircraft accident. FAOC also burdens the other contracting States to the Chicago Convention due to additional requirements and late permission. EASA(European Aviation Safety Agency) is a body governed by European Basic Regulation. EASA was set up in 2003 and conduct specific regulatory and executive tasks in the field of civil aviation safety and environmental protection. EASA's mission is to promote the highest common standards of safety and environmental protection in civil aviation. The task of the EASA has been expanded from airworthiness to air operations and currently includes the rulemaking and standardization of airworthiness, air crew, air operations, TCO, ATM/ANS safety oversight, aerodromes, etc. According to Implementing Rule, Commission Regulation(EU) No 452/2014, EASA has the mandate to issue safety authorizations to commercial air carriers from outside the EU as from 26 May 2014. Third country operators (TCO) flying to any of the 28 EU Member States and/or to 4 EFTA States (Iceland, Norway, Liechtenstein, Switzerland) must apply to EASA for a so called TCO authorization. EASA will only take over the safety-related part of foreign operator assessment. Operating permits will continue to be issued by the national authorities. A 30-month transition period ensures smooth implementation without interrupting international air operations of foreign air carriers to the EU/EASA. Operators who are currently flying to Europe can continue to do so, but must submit an application for a TCO authorization before 26 November 2014. After the transition period, which lasts until 26 November 2016, a valid TCO authorization will be a mandatory prerequisite, in the absence of which an operating permit cannot be issued by a Member State. The European TCO authorization regime does not differentiate between scheduled and non-scheduled commercial air transport operations in principle. All TCO with commercial air transport need to apply for a TCO authorization. Operators with a potential need of operating to the EU at some time in the near future are advised to apply for a TCO authorization in due course, even when the date of operations is unknown. For all the issue mentioned above, I have studied the function of EASA and EU Regulation including TCO Implementing Rule newly introduced, and suggested some proposals. I hope that this paper is 1) to help preparation of TCO authorization, 2) to help understanding about the international issue, 3) to help the improvement of korean aviation regulations and government organizations, 4) to help compliance with international standards and to contribute to the promotion of aviation safety, in addition.

Tco1 is a Hybrid Histidine Kinase Essential for the Sexual Development and Virulence of Ustilago maydis

  • Yun, Yeo Hong;Kim, Seong Hwan
    • 한국균학회소식:학술대회논문집
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    • pp.60-60
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    • 2015
  • Hybrid histidine kinase is a part of two-component system that is required for various stress responses and pathogenesis of pathogenic fungi. In the present study, Tco1, a homologue of human pathogen Cryptococcus neoformans Tco1 encoding a hybrid histidine kinase, was identified in corn smut pathogen Ustilago maydis by bioinformatic analysis. To explore the role of Tco1 in the virulence of U. maydis, mutants in which the tco1 gene was partially deleted were constructed by allelic exchange. The U. maydis tco1 mutants did show unaltered growth rate on axenic medium but were unable to produce conjugation tubes and develop fuzzy filaments, resulting in impaired mating of compatible strains. The expression levels of prf1, pra1, and mfa1 which are involved in the pheromone pathway significantly decreased in the tco1 mutants. In inoculation tests to host, the tco1 mutants showed significantly reduced ability in the production of anthocyanin pigments and tumor development on maize leaves. Overall, the combined results indicated that Tco1 plays important roles in sexual development and virulence of U. maydis by regulating the expression of the genes involved in the pheromone pathway.

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Transparent conductive oxide layers-embedding heterojunction Si solar cells (투명접합을 이용한 이종 태양전지)

  • Yun, Ju-Hyung;Kim, Mingeun;Park, Yun Chang;Anderson, Wayne A.;Kim, Joondong
    • 한국신재생에너지학회:학술대회논문집
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    • pp.47.2-47.2
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    • 2011
  • High-efficient transparent conductive oxide (TCO) film-embedding Si heterojunction solar cells were fabricated. An improved crystalline indium-tin-oxide (ITO) film was grown on an Al-doped ZnO (AZO) template upon hetero-epitaxial growth. This double TCO-layered Si solar cell provided significantly enhanced efficiency of 9.23 % as compared to the single TCO/Si devices. The effective arrangement of TCO films (ITO/AZO) provides a good interface, resulting in the enhanced photovoltaic performances. It discusses TCO film arrangement scheme for efficient TCO-layered heterojunction solar cells.

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Using the mesh electrode for TCO-Iess dye-sensitized solar cells application (메쉬전극을 이용한 TCO-Iess 염료태양전지제작)

  • Jung, Ki-Young;Ju, In-Suk;Sung, Youl-Moon;Kwak, Dong-Joo;Park, Cha-Soo
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • pp.403-405
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    • 2009
  • 본 연구에서는 염료태양전지의 제작 시 고가의 TCO전극을 사용하지 않고 간단히 광전극을 대체할 수 있는 방법으로 메쉬전극을 이용하는 TCO-less 염료태양전지를 제작하였다. 메쉬전극을 이용한 TCO-less 염료태양전지의 구조는 "Glass / 메쉬전극($TiO_2$를 딥코팅 한 후 염료를 흡착시킴) / 전해질 / 멤브레인 필터 / 상대전극(Pt-coated TCO) / Glass" 로 구성된다. 제작된 샘플의 광전변환 효율은 약 1.5% 였으며 fill factor는 0.55로 나타났다. 향후 계획으로 효율을 향상 시킬 수 있는 방법을 도입하여 광전류밀도와 fill factor를 개선하는 연구를 진행할 예정이다.

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