• Title/Summary/Keyword: High-tech

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Genetic Diversity of 10 Indigenous Pig Breeds in China by Using Microsatellite Markers

  • Wang, X.;Cao, H.H.;Geng, S.M.;Li, H.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.9
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    • pp.1219-1222
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    • 2004
  • The genetic diversities of 10 Chinese pig populations were analyzed by using microsatellite DNA polymorphisms. The results showed that the mean heterozygosities of the 10 populations were between 0.4561 and 0.6446, the mean polymorphism information contents were 0.4241-0.6184 and the mean effective number of alleles were 2.4295-3.7573. These indicated that the genetic diversity of local Chinese pigs was high. The clustering of the 10 populations was nearly inaccordance with their geographical distributions.

The Development of 30KVA IGBT-type Customer STATCOM (수용가용 30kVA급 IGBT형 STATCOM 개발)

  • Lim, Su-Saeng;Lee, Eun-Woong;Kim, J.K.;Sohn, H.K.;Cho, H.K.;Jeong, J.H.
    • Proceedings of the KIEE Conference
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    • 2002.07b
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    • pp.657-659
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    • 2002
  • Power quality refers to voltage quality and current quality. Voltage quality means supply reliance such as voltage sag, voltage swell. and short-time interruption. Current quality is related to power factor, harmonic distortion, negative-sequence and zero-sequence current. We fabricated Customer STATCOM to improve current quality such as reactive power, harmonic distortion, and load imbalance. In this paper. We summarize the spec, of STATCOM. its hardware configuration, and control system.

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A Study on the Electrochemical and Thermodynamic Properties of Hydrogen Absorbing Alloys (수소저장합금의 전기화학 및 열역학적 특성에 관한 연구)

  • Park, Chan-Kyo;Cho, Tae-Hwan
    • Journal of Hydrogen and New Energy
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    • v.5 no.2
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    • pp.65-71
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    • 1994
  • Electrochemical and thermodynamic properties of $MmNi_5$ and the related alloys for nickel-metal hydride battery(Ni-MH) were studied in terms of the equilibrium hydrogen pressure. $MmNi_5$ alloy with high equilibrium hydrogen pressure(10~20atm at room temperature), which is usually difficult to charge, was substituted for Al in part. Partial substitution of Al made not only the equilibrium pressure to be reduced remarkably, but also the enthalpy change depending on the formation of metal hydride to be agreed to the value in gas phase reaction and electrochemical reaction. Besides the composition of Al which can be given the maximum discharge capacity was turned out to be between the 0.5~1.0 atoms of Al.

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An Interpretation of the Perspectives of Sustainable Architecture (지속가능한 건축의 계보들)

  • Ryu, Jeon-Hee
    • KIEAE Journal
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    • v.8 no.5
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    • pp.23-34
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    • 2008
  • This paper reviews the relationships between diverse ecological design strategies and competing conceptions of ecological approach in place making. It focuses conceptual trends of what we categorize a building "green" and outlines a social constructive perspective on the development of sustainable architecture. This study classifies seven logics of ecological design-eco-technical, eco-aesthetical, eco-social, eco-medical, eco-renewable, eco-cultural, eco-central - which have their roots in competing philosophies of environmentalism. In my analysis of the logics concerning sustainable architecture, the adapted and incorporated technology from high-tech to low-tech levels is a key issue. These points lead us to propose a way that each logic configures the technological approaches and alternative visions of sustainable places. This paper discusses the implications of the competent nature of plural ecological design perspectives for architectural education, practice, and researches.

Circuit Model Analysis for Traces that Cross a DGS

  • Jung, Kibum;Lee, Jongkyung;Chung, Yeon-Choon;Choi, Jae-Hoon
    • Journal of electromagnetic engineering and science
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    • v.12 no.4
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    • pp.240-246
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    • 2012
  • This paper presents a novel modeling technique for traces that cross a defected ground structure. A simple and accurate equivalent circuit model provides clear insight into the coupling mechanism between a microstrip line and a slot or split. The circuit models consist of a transformer as the coupling mechanism and LC resonators as the ground with a slot or split structure. Resistors, capacitors, and inductors are added to the model to increase accuracy and equivalence at high frequency. Simulated and measured S-parameters are presented for defected ground structures. The accuracy and validity of the proposed equivalent circuit model is verified by evaluation of the S-parameter characteristics of the defected ground structures and comparison with measured results.

An Improved Procedure for 2-amino-5-nitro-4,6-diarylcyclohex-1-ene-1,3,3-tricar Bonitriles; Carbonate on Polymer Support as Mild and Reusable Catalyst

  • Prasanna, T.S.R.;Raju, K. Mohana
    • Journal of the Korean Chemical Society
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    • v.55 no.5
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    • pp.808-811
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    • 2011
  • A new catalytic system has been developed in the synthesis of 2-amino-5-nitro-4,6-diarylcyclohex-1-ene-1,3,3-tricarbonitriles using carbonate on polymer support (Amberlyst A-26 $NaCO_3{^-}$). Short reaction time, simplicity of isolation, safe catalyst and high yields of product are the features.

Research of Electrochemical Properties with Metal Sulfide Electrode for Lithium Batteries (리튬전지용 금속황화물 전극의 전기화학적 특성에 관한 연구)

  • RYU, HO SUK;KIM, IN SOO
    • Journal of Hydrogen and New Energy
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    • v.31 no.1
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    • pp.138-143
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    • 2020
  • Metal sulfides are good candidates for cathode materials. Especially, iron sulfides and nickel sulfides have been demonstrated to be potential electrode materials among metal sulfides due to nontoxicity and high theoretical specific capacities. Electrochemical properties (capacity, cycle life, stability etc.) of Li/iron sulfides or nickel sulfides cell were improved by methode such as coating, doping of material, and nanoization of materials etc.

Enhancement of the Thickness Uniformity of a Phosphor Layer in the Cold Cathode Fluorescent Lamp

  • Kim, Min-Wan;Kim, Hie-Chul;Kim, Suk-Hwan;Lee, Sang-Woo;Choi, Byung-Ho;Kim, Kyung-Hwan;Sohn, Woo-Keun
    • 한국정보디스플레이학회:학술대회논문집
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    • 2004.08a
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    • pp.1068-1071
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    • 2004
  • We report the techniques to obtain the high uniformity of the phosphor film thickness in the cold cathode fluorescent lamps, which are widely used as a back-light for the liquid crystal display. The thickness variation of the phosphor layer was sensitive to blowing conditions. The optimum conditions were obtained at flow rate of 15 sccm for 30 min at 40 $^{\circ}C$. The optimum and uniform thickness of a phosphor layer gives good luminous output.

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A New Active High Power Factor Diode Rectifier System (새로운 능동형 고역률 다이오드 정류기시스템)

  • Kim H.J.;Choi S.W.;Won C.Y.;Kim G.S.
    • Proceedings of the KIPE Conference
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    • 2003.07a
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    • pp.269-274
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    • 2003
  • 본 논문에서는 2대의 다이오드 정류기에 부스트 컨버터를 이용하여 전류의 파형을 능동적으로 만들어 정현파의 입력전류를 얻는 새로운 방식의 고조파 저감방식을 제안한다. 제안한 당식으로 역률 1의 전원 품질을 얻을 수 있으며 입력측의 변동에 대한 출력전압의 조정도 가능하다. 또한 저감된 용량을 갖는 3상 오토 트랜스포머의 사용으로 기존의 $\Delta$-Y 변압기에 비해 KVA정격이 80$\%$ 절감되며 상간변압기도 필요 없다. 본 방식을 소형화와 고품질의 전원이 요구되는 통신용 정류기등에 적용하면 효과적이다. 제안한 방식의 동작원리, 제어 및 설계방법을 기술하고 1.5KW급 시작품으로부터의 실험결과를 제시한다.

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Study on the manufacturing of high-frequency heating Japanese cedar laminated board by finger jointing method (1) - Gluing characteristics of Japnese cedar board by PVAc emulsion adhesives - (핑거접합방식에 의한 삼나무의 고주파가열 집성판 제조에 관한 연구 (1) - 삼나무 판재의 초산비닐수지 접착특성 -)

  • So Won-Tek;Chai Jyung-Ki
    • Journal of the Korea Furniture Society
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    • v.16 no.1
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    • pp.1-8
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    • 2005
  • This experiment was carried out to investigate the gluing characteristics of poly vinyl acetate emulsion adhesive(PVAc) on the Cryptomeria japonica laminated boards. This sample trees are major planting species and have been planted in southern district for a long time. The optimum gluing conditions for laminated board were summarized as follows; the amount of spreading glue, assembly time, clamping pressure, and clamping time for PVAc resin were $200g/m^2$, 10min., $5kg/cm^2$, and 6hrs., respectively, and the relative formulae between extension ratio(x) and block shear strength(y) was $y=-9.6x+85.2(R^2=0.95)$.

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