• Title/Summary/Keyword: present phase

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Overview of the Current Status of Technical Development for a Highly Scalable, High-Speed, Non-Volatile Phase-Change Memory

  • Lee, Su-Youn;Jeong, Jeung-Hyun;Cheong, Byung-Ki
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.8 no.1
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    • pp.1-10
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    • 2008
  • The present status of technical development of a highly scalable, high-speed non-volatile PCM is overviewed. Major technical challenges are described along with solutions that are being pursued in terms of innovative device structures and fabrication technologies, new phase change materials, and new memory schemes.

The Analysis of Characteristics for Digital PLL Control (디지털 PLL 제어의 특성 분석)

  • Kim Y.K.;Choi J.W.;Kim H.G.
    • Proceedings of the KIPE Conference
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    • 2003.07b
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    • pp.548-553
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    • 2003
  • The frequency and phase angle of the utility voltage are important in many industrial systems. this paper present a detailed analysis of single-phase digital PLL control for utility connected systems. and its performance under utility conditions with noise is discussed. The experimental results demonstrate phase tracking capability in the single-phase grid-connected operation.

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Phase-Shifted Fiber Bragg Grating Transmission Filters Based on the Fabry-Perot Effect

  • Liu, Y.u;Lee, S. B.;Choi, S. S.
    • Journal of the Optical Society of Korea
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    • v.2 no.1
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    • pp.30-33
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    • 1998
  • We present the analysis of phase-shifted fiber Bragg gratings by coupled-mode equations. The transmission is expressed as that of a Fabry-Perot resonator with complex reflectance and complex transmittance. The transmission spectrum, the effective cavity length, and the behaviors with different phase-shifts are investigated. A very flattered transmission peak is obtained by introducing three phase-shifts in a grating.

Design management's development direction through design process improvement (설계업무 프로세스 개선을 통한 설계관리의 발전 방향)

  • Kim, Han;Kim, Seon-Gyoo;Lee, Nak-Woon
    • Journal of Industrial Technology
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    • v.27 no.B
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    • pp.169-176
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    • 2007
  • Recently, construction industry has been magnified while various cooperative relationship makes steady process. So importance of management during construction is gathering strength. Therefore, we need systematic management gradually. But almost management of construction industry that performs these day is focused on construction phase not design phase. The purpose of the present study is to find the effective way of design management with enhancing the process of design phase.

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Common-path phase microscopy for lives cell imaging (살아있는 세포 영상획득을 위한 common-path phase microscopy)

  • Lee, Ji-Yong;Lee, Seung-Rak;Yang, W.Z.;Kim, Deok-Yeong
    • Proceedings of the Optical Society of Korea Conference
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    • 2008.07a
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    • pp.273-274
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    • 2008
  • We present a quantitative phase microscopy for live cells. This method uses the principles of common path inteferometry and single shot phase image. This system has the ability to measure live cells quantitatively with subnanometer path length stability and millisecond scale aquisition time.

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Optical Properties of Admolecules near a Phase -Conjugate Mirror (위상 공액 거울에 흡착된 분자의 광학적 성질)

  • 김영식
    • Journal of the Korean Vacuum Society
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    • v.5 no.1
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    • pp.33-38
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    • 1996
  • The induced linewidth, frequency shift and absorption spectrum for a molecular dipole in the vicinity of a phase -conjugate mirror have been investgated within a classical phenomenological model, with particularreference to the technique of optical phase conjugation by a surface. While the shifts and the widths show similar characteristics as those obtained recently by Bochove who considered the problem within the context of four-wave mixing, the results obtained in the present model can be defined uniquely with the possibility of an infinite lifetime for the excited admolecule . Furthermore, the absorption lineshape obtained here some interesting features which depend on both the magnitude and the phase of the complex reflectivity of the mirror.

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The Phase Error Analysis in the Shearographic System using Wave plates (파장판을 이용한 Shearographic system에서의 위상오차 분석)

  • Kim, Soo-Gil;Ko, Myung-Sook
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2005.11a
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    • pp.185-188
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    • 2005
  • We present the method to obtain four speckle patterns with relative phase shift of ${\pi}/2$ by passive devices such as wave plate and polarizer, and calculate the phase at each point of the speckle pattern in shearographic system using Wollaston prism. And, we analyzed the phase error caused using wave plates by Jones matrix.

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Precipitation Behavior of Laves Phase in 10%Cr Ferrite System Alloy (10%Cr 페라이트계 합금에서 라베스상의 석출거동에 관한 연구)

  • Kim, I.S.;Kang, C.Y.;Bae, D.S.
    • Journal of the Korean Society for Heat Treatment
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    • v.12 no.1
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    • pp.21-30
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    • 1999
  • The present study were investigated changes of precipitation behaviour of laves phase in ferrite single phase and ferrite-martensite dual phase and precipitation of laves phase under stress. Hardness changes in ferrite phase appeared two hardness peaks by precipitation of initial fine precipitator and laves phase in 3Mo-0.3Si and 3Mo-0.3Si-C specimens, respectively. Hardness changes in martensite phase of 3Mo-0.3Si-C specimen was lower in the initial stage of aging by carbide precipitation and after this, increased by re-hardening due to precipitation of laves phase. In the ferrite phase, laves phase was mainly precipitated, whereas in the martensite phase, carbide was preferentially formed during the initial stage of aging and with increasing aging time, laves phase and carbide were simultaneously precipitated by precipitation of laves phase at around carbide. In the ferrite-martensite interface, laves phase was mainly precipitated and carbide was mainly formed at boundary of lath martensite than grain boundary. Adding the stress in aging, fine precipitator of inital precipitation of laves phase precipitated in (100) of perpendicular to tensile direction and has grown to only followed<010>direction and also, volume fraction of laves phase increased. Consequently, the stress added was accelerated initial precipitation of laves phase.

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Phase Separation and their Structures in $BaO-B_2O_3$ Glasses ($BaO-B_2O_3$계 유리의 상분리 현상과 유리의 구조)

  • 채수철;김철영
    • Journal of the Korean Ceramic Society
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    • v.23 no.6
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    • pp.25-32
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    • 1986
  • Phase spearated glass is heterogeneous in microscopic point of view and the heterogeneities affect the structures of glasses. In the present work the phase separation of $BaO-B_2O_3$ glass system was investigated and the effect of $P_2O_5$ on the phase separation and crystallization was also studied in the above system. Experiments such as scanning electron microscopy X-ray diffraction and infrared spectroscopy were performed. Phase separation with $B_2O_3$ rich phase matrix and BaO rich phase droplet was observed for the glasses containing less than 6 mole% of BaO while the opposite morphology of phase separation was found for the glasses containing more than 7 mole% of BaO. Phase separation region was extended up to the glass with 22mole% of BaO when the amount of $P_2O_5$ was increased. The heat-treated glasses crystallized to BaO.$4B_2O_3$$P_2O_5$ hindered the glass from the crystalli-zation.

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A Study on Quantitative Performance Index for Phase-Change Cooling Systems (상변화 냉각시스템의 정량적 성능지수 연구)

  • Jang, Myeong-Eon;Song, Hye-Eun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.23 no.3
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    • pp.237-245
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    • 2020
  • In this paper, I introduce Phase-Change Cooling for thermal management of high power devices that can be applied to High Power Laser and Electric Propulsion Systems which are composed of multiple distributed superheat sources. Phase-Change Cooling can be good used to efficient cooling of their heat sources. Phase-Change Cooling has extremely high efficiency of two-phase heat transport by utilizing heat of vaporization, relatively low flow rates and reduced pumps power. And I suggest TPI(Thermal Performance Index) which is a quantitative performance index of Phase-Change Cooling for thermal management. I quantify the performance of Phase-Change Cooling by introducing TPI. I present the test results of TPI's changing refrigerant, heat sink and flow rate of the Phase-Change Cooling system through the experiments and analyze these results.