• 제목/요약/키워드: 김양배

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  • 한국건강관리협회
    • 건강소식
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    • 제20권2호통권207호
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    • pp.48-49
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    • 1996
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마그네트론 구동용 인버터의 특정 고조파 제거에 관한연구 (Studies on the Particular harmonics Elimination inverter Magnetron drive)

  • 김양배;황정호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2015년도 제46회 하계학술대회
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    • pp.1296-1297
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    • 2015
  • 마이크로 웨이브를 사용하는 기기들은 대량생산 공정에 있어서 식품 가공용 건조기기로 사용되고 있다. 3kW 마그네트론을 구동하기 위해서는 필라멘트를 가열하고 고압의 DC전원을 발생할 수 있는 회로가 필요하게 된다. 반도체 소자를 이용한 전력변환 장치로 DC로 운전이 되면 AC계통으로 혼입되는 고조파가 발생된다. 본 논문에서 AC계통으로 유입되는 특정고조파 제거 방법을 제안한다. 고조파 검출회로를 기반으로 전류를 제어함으로써 기존 LC필터에서 제거되지 못한 고조파성분이 감쇠되는 성능을 보였다.

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혼합용매중의 지시약 Phenol Red의 해리정수 (The Dissociation Constant of Phenol Red Indicator in Mixed Solvents)

  • 김양배
    • 약학회지
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    • 제20권1호
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    • pp.41-43
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    • 1976
  • The dissociation constant of phenol red indicator in mixed solvents was studied. Methanol and ethanol were employed as solvents and studied the changes of pK values of indicator according to the kind and concentration of organic solvent which is mixed into water solution. The effect of methanol solvent on pK is negligible at 40%, 60% and 80% mixing. While in the case of ethanol, the effect of above 40% mixing is not negligible.

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크라이신 사이크로푸로판카복실레이트의 육모효과 (Hair-growth Effect of Chrysin 7-O-cyclopropanecarboxylate)

  • 장지면;이명철;신준수;정재훈;김양배;김박광
    • Biomolecules & Therapeutics
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    • 제9권1호
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    • pp.15-19
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    • 2001
  • The derivative of chrysin 7-O-cyclopropanecarboxylate was synthesized by condensing cyclopropanecarboxylic acid with chrysin in organic solvent, and its structure was identified by NMR, MS, UV IR etc. We also investigated the physico-chemical properties, anti-diabetic effect and set up the quantitative analytical method of this compound. The correlation coefficient of calibration curve on this compound was approximately 0.9985 by absorption spectrophotometry. And, this study was carried out to investigate the hair-growth effect of chrysin derivative to the black mouse (C57BL/6). When this derivative in ethanol solution was administered to the back of mouse by method of skin paste, this derivative promoted the hair growth of mouse.

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재생골재를 사용한 콘크리트의 강도에 미치는 포졸란 시멘트 효과 (Effect of the Pozzolanic Cement on Concrete Strengths with Recycled Aggregate)

  • 문대중;임남웅;김양배
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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    • pp.217-220
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    • 2001
  • Due to the tendency of increase in demolished-concrete produced by alteration and deterioration of concrete structures, recycling of those demolished-concrete is necessary to solve the exhaustion of natural aggregate, in order to save resources and protect environment, especially being want of resources in Korea. For this purpose, concrete made with the pozzolanic cement and recycled aggregate was tested for compressive and tensile strength. The pozzolanic cement was a mixture of OPC(Ordinary Portland Cement) and pozzolans such as fly ash, other siliceous materials and early rapid hardening cement(ERC). It was found that the compressive strength of the pozzolanic cement was enhanced when 0.75% of ERC was dozed, as compared with OPC mortar. It was also shown that compressive and tensile strength of concrete with recycled aggregate and pozzolanic cement were higher than those of concrete with crushed stones and OPC. It was concluded that the pozzolanic cement influenced on the increase of concrete strengths with recycled aggregate.

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포졸란 재료를 사용한 재생골재 콘크리트의 건조수축 및 크리프 (Shrinkage and Creep of Recycled Aggregate Concrete Using Pozzolanic Materials)

  • 문대중;임남웅;김양배
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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    • pp.637-642
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    • 2002
  • In this study, the experiments of recycled aggregate concrete with fly ash and special blended slag powder or diatom calcined at 650$\circ$ were performed on compressive strength, shrinkage and creep. The compressive strength of concrete with recycled aggregate and pozzolanic materials were higher than that of concrete with crushed stone and OPC. On the other hand, the shrinkage and creep of concrete with recycled aggregate and pozzolanic materials was smaller than that of concrete with crushed stone and OPC. Futhermore, the shrinkage and creep of recycled aggregate concrete with fly ash and special blended slag powder was a little decreased that of recycled aggregate concrete with fly ash and diatom. Relationship between compressive strength and creep coefficient was shown to the linear relation like as $\sigma$$_{c}$= -30CF+404.4.

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