• 제목/요약/키워드: Research laboratory

검색결과 16,299건 처리시간 0.036초

Evaluation of Turbidity Generated by Cutter Suction and Grab Dredgers

  • Jin, Jae-Youll;Song, Won-Oh;Park, Jin-Soon;Kim, Sung-En;Oh, Young-Min;Yum, Ki-Dai;Oh, Jae-Kyung
    • 한국해안해양공학회:학술대회논문집
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    • 한국해안해양공학회 2003년도 한국해안해양공학발표논문집
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    • pp.179-184
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    • 2003
  • It is inevitable for dredging to increase the suspended sediment concentration (SSC) of the ambient waters in some degree, which has the potential to affect the coastal ecosystem in various manners. Thus, quantitative under- standing of dredging-induced sediment loss is essential fur the reliable environmental impacts assessment. (omitted)

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MgO Sputtering in the AC-PDPs with Monte Carlo Methods

  • Gill, Doh-Hyun;Kim, Hyun-Sook;Joh, Dae-Guen;Kim, Young-Guon;Choi, Eun-Ha;Cho, Guang-Sup
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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    • pp.109-110
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    • 2000
  • Sputtering yield of MgO film in the AC-PDPs has been calculated by Monte Carlo simulation of ion scattering. In the ion energy range less than 50 eV, the sputtering yield is 4 ${\times}$ $10^{-4}$ for Xe ions and it is between 0.1 and 0.01 for He, Ne, and Ar ions. The erosion rate is estimated about $25{\AA}$ per hour for Xe ions in an actual PDP plasma for sustain and full white mode.

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Surface Discharge in Various Electrode Geometries

  • Joh, Dai-Geun;Kim, Hyun-Sook;Gill, Do-Hyun;Kim, Young-Goun;Choi, Eun-Ha;Cho, Guang-Sup
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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    • pp.111-112
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    • 2000
  • The breakdown characteristics of surface discharge investigated experimentally agree well with the analytic results of previous reports [1-3] in various electrode geometries. Additionally, we find that the electrode geometry effects on the firing voltage can be understood with the ionization probability relating to the number of priming particles. We have also observed the shape of surface discharge and the surface striations in the gap geometry with the pressure, the applied voltage, and the driving frequency.

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Blue-Emitting CaS:Pb Thin Film Electroluminescent Devices Fabricated by Controlled Atomic Layer Deposition

  • Yun, Sun-Jin;Kim, Yong-Shin;KoPark, Sang-Hee;Kang, Jung-Sook;Cho, Kyoung-Ik;Ma, Dong-Sung
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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    • pp.149-150
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    • 2000
  • Lead-doped calcium sulfide(CaS:Pb) thin film electroluminescent devices were deposited using atomic layer deposition(ALD). CaS:Pb is a very promising blue phosphor showing very high luminance and the color coordinate close to the blue of cathode ray tube. The luminance, $L_{25}$, of CaS:Pb(1.6 mol.%) EL device was higher than 80 $cd/cm^2$ at a driving frequency of 60Hz. The color coordinates of blue EL emission of CaS:Pb deposited by ALD are consistent with the Pb concentration ranging from approximately 0.5 to 3 mol.%.

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Mild Isomerative Opening of Tetrahydrofuranyl Subunits in Steroids Using TFAT (trifluoroacetyl trifluoromethanesulfonate): Application to Synthesis of C17-OH Rockogenin Acetate

  • Lee, Jong-Seok;Kim, Byung-Sook;Shin, Jun-Ho;Lee, Yeon-Ju;Shin, Hee-Jae;Lee, Hyi-Seung
    • Bulletin of the Korean Chemical Society
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    • 제33권1호
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    • pp.76-82
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    • 2012
  • A novel and efficient tetrahydrofuranyl ring opening method was developed using the highly reactive TFAT reagent in the presence of an acid scavenger, 2,6-di-tert-butyl-4-methylpyridine. Various acid sensitive groups are compatible with the reaction condition, making it generally applicable to many tetrahydrofuranyl steroids. Moreover, it is a synthetic equivalent of 'Marker degradation' affording an efficient synthesis of C17-OH rockogenin acetate.

An Efficient Synthesis of 2,4,5-Triaryl-1H-Imidazole Derivatives Catalyzed by Boric Acid in Aqueous Media Under Ultrasound-Irradiation

  • Shelke, Kiran F.;Sapkal, Suryakant;Sonal, Swapnil;Madje, Balaji R.;Shingate, Bapurao B.;Shingare, Murlidhar S.
    • Bulletin of the Korean Chemical Society
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    • 제30권5호
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    • pp.1057-1060
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    • 2009
  • Boric acid ($BO_3H_3$) is an inexpensive, efficient and mild catalyst for the synthesis of 2,4,5-triaryl-1H-imidazoles in excellent yields from the one-pot three-component condensation of benzil/benzoin, an aldehydes and ammonium acetate in aqueous media under ultrasound at room temperature. The remarkable advantages offered by this method are green catalyst, mild reaction conditions, simple procedures, much faster reactions and excellent yield of products.

Estimation of the Efficiency of a Silt Screen using a Vessel-mounted ADCP

  • Jin, Jae-Youll;Park, Jin-Soon;Song, Won-Oh;Kim, Sung-En;Lee, Kwang-Soo;Yum, Ki-Dai;Oh, Jae-Kyung
    • 한국해안해양공학회:학술대회논문집
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    • 한국해안해양공학회 2003년도 한국해안해양공학발표논문집
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    • pp.353-358
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    • 2003
  • As fur quantitative evaluation of the amount of sediments released into the ambient waters by various works fur coastal development, the instrument and method of the measurement of suspended sediment concentration (SSC) are critical for estimating the efficiency of a silt screen to reduce the spreading of sediment plumes generated by coastal works. (omitted)

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