• 제목/요약/키워드: $K_s$

검색결과 199,122건 처리시간 0.186초

Vitrification of Bovine Immature Oocytes using Microdrop Method

  • Park, H.S.;Kim, D.H.;Kim, S.W.;Yang, B.C.;Im, G.S.;Hwang, I.S.;Seo, J.S.;Yang, B.S.;Moon, S.J.;Chang, W.K.
    • 한국동물번식학회:학술대회논문집
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    • 한국동물번식학회 2004년도 춘계학술발표대회
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    • pp.258-258
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    • 2004
  • Successful cryopreservation of mammalian oocytes would provide a source of materials for in vitro embryo production. This study was conducted to determine vitrification conditions for bovine immature oocytes using micro-drop method and, to examine maturation, fertilization and development of vitrified bovine immature oocytes. (omitted)

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진노랑상사화 Lycoris chinensis Traub var. sinuolata K. Tae et S. Ko ex K. Tae et S. Ko (Amaryllidaceae)에 대한 기재 (Description of Lycoris chinensis Traub var. sinuolata K. Tae et S. Ko ex K. Tae et S. Ko (Amaryllidaceae))

  • 태경환;고성철
    • 식물분류학회지
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    • 제33권4호
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    • pp.387-392
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    • 2003
  • 본 연구는 신종 발표시 기록하지 않았던 진노랑상사화 Lycoris chinensis Traub var. sinuolata K. Tae et S. Ko에 대하여 라틴어 기재를 추가하였고, 또한 근연관계에 있는 L. chinensis Traub와 L. aurea Herb를 포함한 새로운 분류군에 대한 검색표를 제시하였다.

Some Characterizations of Catenary Rotation Surfaces

  • Kim, Dong-Soo;Kim, Young Ho;Yoon, Dae Won
    • Kyungpook Mathematical Journal
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    • 제57권4호
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    • pp.667-676
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    • 2017
  • We study the positive $C^1$ function z = f(x, y) defined on the plane ${\mathbb{R}}^2$. For a rectangular domain $[a,b]{\times}[c,d]{\subset}{\mathbb{R}}^2$, we consider the volume V and the surface area S of the graph of z = f(x, y) over the domain. We also denote by (${\bar{x}}_V,\;{\bar{y}}_V,\;{\bar{z}}_V$) and (${\bar{x}}_S,\;{\bar{y}}_S,\;{\bar{z}}_S$) the geometric centroid of the volume under the graph of z = f(x, y) and the centroid of the graph itself defined on the rectangular domain, respectively. In this paper, first we show that among nonconstant $C^2$ functions with isolated singularities, S = kV, $k{\in}{\mathbb{R}}$ characterizes the family of catenary rotation surfaces f(x, y) = k cosh(r/k), $r={\mid}(x,y){\mid}$. Next, we show that one of $({\bar{x}}_S,\;{\bar{y}}_S)=({\bar{x}}_V,\;{\bar{y}}_V)$, $({\bar{x}}_S,\;{\bar{z}}_S)=({\bar{x}}_V,\;2{\bar{z}}_V)$ and $({\bar{y}}_S,\;{\bar{z}}_S)=({\bar{y}}_V,\;2{\bar{z}}_V)$ characterizes the family of catenary rotation surfaces among nonconstant $C^2$ functions with isolated singularities.

Enhanced Photosensitivity in Monolayer MoS2 with PbS Quantum Dots

  • Cho, Sangeun;Jo, Yongcheol;Woo, Hyeonseok;Kim, Jongmin;Kwak, Jungwon;Kim, Hyungsang;Im, Hyunsik
    • Applied Science and Convergence Technology
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    • 제26권3호
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    • pp.47-49
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    • 2017
  • Photocurrent enhancement has been investigated in monolayer (1L) $MoS_2$ with PbS quantum dots (QDs). A metal-semiconductor-metal (Au-1L $MoS_2$-Au) junction device is fabricated using a standard photolithography method. Considerably improved photo-electrical properties are obtained by coating PbS QDs on the Au-1L $MoS_2$-Au device. Time dependent photoconductivity and current-voltage characteristics are investigated. For the QDs-coated $MoS_2$ device, it is observed that the photocurrent is considerably enhanced and the decay life time becomes longer. We propose that carriers in QDs are excited and transferred to the $MoS_2$ channel under light illumination, improving the photocurrent of the 1L $MoS_2$ channel. Our experimental findings suggest that two-dimensional layered semiconductor materials combined with QDs could be used as building blocks for highly-sensitive optoelectronic detectors including radiation sensors.

IN 617의 아결정립계의 전위간격 분석법에 관한 고찰 (Observation and Analysis of Dislocation Spacing in the Subgrain boundary on IN 617)

  • 안성욱;이종민
    • 한국재료학회지
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    • 제5권2호
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    • pp.184-190
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    • 1995
  • IN 617의 시편으로 1073K의 온도에서 주로 107과 180MPA의 응력에서 $\varepsilon$=0.03-0.30까지 정압크립변형을 하여, 투과전자현미경(TEM)에서 약 십만배의 배율로 아결정립의 전위간 거리 s를 측정하고, TEM에서 측정이 불가능한 경우, 아결정립계가 이루는 각도 ($\theta$_{s}=sin^{-1}$(b/s))를 Kikuchi line을 이용하여 측정하였다. TEM에서 직접 구한 s 값들을 $\theta$_{s}$값으로 환산하여, Kikuchi line으로 측정한 $\theta$_{k}$값을 비교한 결과 거의 같았다.즉, TEM에서 s의 측정이 불가능할 때, $\theta$_{k}$를 측정하여 s값으로 사용하여도 됨을 알 수 있었다.

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A study on SFCL application for the interconnection operation of 154kV power systems under 345kV S/S in Korean power system

  • Lee Seung Ryul;Kim Jong Yul;Yoon Jae Young
    • 한국초전도ㆍ저온공학회논문지
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    • 제7권2호
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    • pp.47-51
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    • 2005
  • This paper is for studying the feasibility of SFCL application for the interconnection operation of 154kV power systems under 345kV S/S in Korean power system. All Korean 154kV power systems are constructed as loop systems in downtown. However, the present 154kV systems are operated with separated systems around 345kV S/S because of fault current and overload problems. In this study, we investigate the structure and operation of 154kV power system in Seoul and study the feasibility of interconnection operation of 154kV systems under 345kV systmes by applying SFCLs to 154kV bus-tie.