• Title/Summary/Keyword: firing

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싸이리스터 제어 SVC를 포함하는 전력계통에서의 스위칭 점화각에 의한 고유치 해석 (Eigenvalue Analysis of SVC's Thyristor Firing Angles in Power System)

  • 이윤호;동무환;김덕영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.16-17
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    • 2006
  • In this paper, RCF analysis method which is very powerful to analyze non-continuous systems with switching elements is applied to small signal stability problems. As an effect of switching operations, the eigenvalues of system can be changed and newly unstable oscillation modes may be occurred. Also, changing firing angles of switching equipments may make the system stable or unstable. As an illustrating example, the oscillation modes of the system with different firing angles are computed by the RCF analysis method.

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바이오 가스를 사용하는 가스터빈 열병합 시스템의 전부하 및 부분부하 운전특성 해석 (A Study on Full and Part Load Operations of a Biogas-fired Gas Turbine Combined Heat and Power System)

  • 강도원;이종준;김동섭;허광범
    • 한국유체기계학회 논문집
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    • 제14권2호
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    • pp.35-40
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    • 2011
  • This study analyzed the influence of firing biogas on the performance and operation of a gas turbine combined heat and power (CHP) system. A reference CHP system designed with natural gas fuel was set up and off-design simulation was made to investigate the impact of firing biogas in the system. Changes in critical operating parameters such as compressor surge margin and turbine blade temperature caused by firing biogas were examined, and a couple of operating schemes to mitigate their changes were simulated. Part load operation of the biogas-fired system was compared with that of natural-gas fired system, and it was found that as long as the two system produce the same electric power output, they exhibit nearly the same heat recovery.

Luminescence of $Eu^{3+}$ and $Sm^{3+}$ Doped Potassium Tungstate Phosphors

  • Lee, Gwan-Hyoung;Kang, Shin-Hoo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1510-1513
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    • 2005
  • The luminescent properties of $Eu^{3+}$ and $Sm^{3+}$ doped potassium tungstate phosphor were investigated. The $K_{4-3x}(WO_4)_2:Eu_x$, $Sm_y$ phosphor was produced by firing the mixed precursors, followed by re-firing with a flux. The re-firing process provided the clean surface to the particles. The excitation spectra showed that the strong absorption in the region of ultra violet light occurred due to the high europium doping concentration. The incorporation of europium to potassium tungstate was easier, compared to other host materials. The excitation spectra could be controlled by the small addition of samarium. The increase of energy absorption around 405nm was assigned to the $Sm^{3+}$ ions. The comparison between real x-ray diffraction and simulated one revealed that the crystal structure of $K_{4-3x}(WO_4)_2:Eu_x,Sm_y$ phosphor is monoclinic with a space group, C2/c.

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도염식 가스가마의 설계 I.설계 (Design of Down Draft Kiln for Gas Firing-I. Design)

  • 이기강;김환;임응극
    • 한국세라믹학회지
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    • 제23권6호
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    • pp.7-14
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    • 1986
  • This work is concerned with the experimental and theoretical investigation of a kiln with the aim to obtain th best conditions of firing in a kiln, The 0.3$m^3$ down draft kiln of gas firing was designed and constructed. Temperature distributions in kiln combustion gas temperature primary and secondary air flow were measured in the kiln burnt with propane LP gas. And the temperature distri-butions of kiln surface were measured by the thermo camera.

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식기용 자기소지에 관한 연구 (A Study on the Dinnerware Porcelain Bodies)

  • 장승현;정형진
    • 한국세라믹학회지
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    • 제19권3호
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    • pp.241-249
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    • 1982
  • Two dinnerware porcelain bodies involving partial replacement of feldspar and kaoline by about 35wt% domestic GYUNGJU-pottery stone were developed and their properties such as shrinkage, porosity, firing range, linear thermal expansion, pyroplastic deformation, degree of whiteness and mechanical strength were compared with those of a traditional clay-flint-feldspar body. The experimental results showed that one of the clay-flint-feldspar-pottery stone body with 1% ZnO addition had the firing range of 115$0^{\circ}C$~121$0^{\circ}C$, whereas the traditional body had the firing range of 12$25^{\circ}C$~129$0^{\circ}C$. The linear drying shrinkage and linear dry-to-fired shrinkage of all bodies were 2.5~4.5% and 15~18%, respectively. And the major crystalline phases of sintered bodies were $\alpha$-quartz and secondary mullite surrounded by glassy phases. The modulus of rutpture of sintered bodies was ranged from 860 to 870kg/$\textrm{cm}^2$, and the microhardness of sintered bodies was 680 kg/$\textrm{cm}^2$.

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고공모사 환경에서의 1 Ibf급 단일액체추진제 로켓엔진 연소성능시험 (Hot Firing Performances of 1 lbf-Liquid Monopropellant Rocket Engine under the Environment of High Altitude Simulated)

  • 김정수;한조영;이균호;황도순;장기원;이재원;강주성;정종록;조대기
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2003년도 제20회 춘계학술대회 논문집
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    • pp.189-192
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    • 2003
  • 추진제 주입 압력 350 psi 에서 0.95 lbf 의 정상상태 공칭추력을 내는 단일액체추진제 하이드라진 추력기의 검증을 위한 성능 요구조건과 시험결과를 요약한다. 성능특성은 정상상태 및 펄스 모우드 연소상태에서의 추력 거동으로 제시되고 지상연소시험과정이 간략히 소개된다.

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총기 경사도에 따른 명중률 변화에 관한 연구 (A Study on Variation of an Accuracy Rate as the Gradient of a Pistol)

  • 여운주;이준호;최의중
    • 한국군사과학기술학회지
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    • 제14권2호
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    • pp.167-172
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    • 2011
  • In this paper, a study on variation of an accuracy rate as the gradient of a rifle is shown. In the a state of hostilities, a soldier is not easy to take a shot vertically against the ground. If a soldier shoots as the pistol is inclined, how the accuracy rate is changed. While the pistol is shot, the change of ballistic curve is estimated. And we also verify the accuracy rate through the firing test. Then we compare two results and present some ideas which overcome the decrease of an accuracy rate. Hereafter, it is possible to adapt in the future soldier system and expected that the accuracy rate of the conventional gun is maintained.

Comb형 전극구조를 갖는 AC 플라즈마 디스플레이 패널의 방전특성 (Discharge Properties of an AC Plasma Display Panel with Comb-Type Electrodes)

  • 김동수;장지근;임성규;장호정
    • 한국재료학회지
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    • 제9권2호
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    • pp.195-198
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    • 1999
  • The newly designed Ac-PDP(plasma display panel with comb-type electrode) structure was fabricated by using the screen printing method and the electrical and optical characteristics were measured under the various discharge conditions. The minimum firing voltages measured under pure Ne and Ne+Xe mixture gas with the application of 10 kHz square wave were 190V and 160V, respectively. The firing voltages of the PDP cell with the comb-type electrode were compared with those of the cell with matrix electrode under the same discharge condition. The firing voltage of the PDP cell with comb-type electrode was 15 V lower than that of the PDP cell with conventional matrix electrodes.

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대용량 전력변환용 사이리스터 디지털 점호제어 (Digital firing control for high power thyristor converter)

  • 이영복;김장목;임익헌;류호선;송승호
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2003년도 춘계전력전자학술대회 논문집(2)
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    • pp.565-568
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    • 2003
  • The conventional analog-based firing circuit can be implemented by comparing a linearly decreasing periodic sawtooth waveform synchronized to the ac line, with a voltage corresponding to the desired converter delay angle. This circuit requires a large number of components (resistance and capacitor) and careful adjustment of the synchronization circuity In this paper a novel firing circuit is proposed for thyristor switch is elements. The proposed circuit is implemented on the basis of the analog cosine method using FPGA and microprocessor.

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A New Firing Process Method by Using RTS System for Transparent Dielectric Layer of PDP

  • Kim, Song-Kwan;Yun, Hae-Sang;Kim, Young-Cho;Yoon, Cha-Keun;Whang, Ki-Woong;Park, Sun-Woo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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    • pp.187-188
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    • 2000
  • The conventional firing process method for the transparent dielectric layer in PDP Technology has disadvantages of low through put, high power consumption and large process area. We propose the rapid thermal scinterring (RTS) method as new process method to overcome these disadvantage characteristics. As the experimental result of this method, the optic transmittance(wavelength : 600nm) rate of transparent dielectric layer was more improved than conventional furnaces under the optimized gas supplying. Further, it was certified this method had the best conditions on the firing process of the PDP transparent dielectric layer.

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