• 한국자기학회지
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• 제3권1호
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• pp.56-60
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• 1993

FeCo/Pd 초격자 다층박막의 FeCo 와 Pd sublayer 두께를 각각 $2.5\;{\AA}$ 및 $10.5\;{\AA}$으로 유지시키면서 FeCo sublayer 의 Fe 조성이 0에서 100% 까지 변화함에따른 포화자화값, 수직 자기이방성에너지, 보자력 및 Kerr 회전각의 파장 의존성을 조사 하였다. 포화자화값은 Fe 조성이 48 at.%부근에서 최 고치를 보였고, 수직 자기이방성에너 및 조자력은 Fe조성의 증가에따라 단조감소 하였다. Kerr 회전각은 Fe 조성의 증가에따라 감소하였는데 그 크기 및 변화의 폭은 단파장으로 갈수록 증가하였다.

• Macromolecular Research
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• 제11권3호
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• pp.163-171
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• 2003

For the pervaporation of water-ethanol mixtures, new composite membranes having poly(acrylic acid)-poly (butyl methacrylate-co-methyl methacrylate) interpenetrati ng polymer network [PAA-P(BMA-co-MMA) IPN] skin layer supported on porous and crosslinked poly(BMA-co-MMA) were prepared. The morphology of the sub-layer of the composite membrane prepared in the presence of 60 wt% solvent showed cellular structure, on the other hand that of sublayer prepared in the presence of 70 wt% solvent presented very porous interconnected pore structure with macrovoids. Permeation rates of the composite membranes were largely influenced by the morphology of the sublayer. Separation factors increased with the increase of the degree of crosslinking of the PAA network. It was found that permeation rates could be increased by introducing anionic charges on carboxyl groups of the PAA. The permeation rate changes of the PAA-P(BMA-co-MMA) IPN composite membranes according to the feed compositions showed quite similar pattern with the swelling behavior in water-ethanol mixtures.

• Journal of Magnetics
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• 제8권4호
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• pp.146-148
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• 2003

Multilayered films of Co/Pd have been studied as a candidate material for a high density perpendicular recording medium due to higher anisotropy energy. However, high exchange coupling among grains results in large transition noise. To reduce the exchange coupling and grain size, addition of 3rd elements and physical separation of grains have been attempted. In the present paper, effects of sputtering pressure, Co sublayer thickness and Pd underlayer thickness on magnetic properties and microstructures were studied. It was found that by increasing sputtering pressure from 5 mTorr to 25 mTorr, Ms decreased to one half and coercivity increased more than 5000 Oe. The increase of the coercivity is associated with physical separation of grains by high pressure sputtering. Ms per volume of Co for Co/Pd multilayered film deposited at 25 mTorr shows continuous decrease with increasing Co sublayer thickness. This was related to void formation and intermixing of Co/Pd interface. Also, effect of Pd underlayer thickness on magnetic properties will be discussed.

• 한국자기학회지
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• 제5권5호
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• pp.470-473
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• 1995

We have constructed an apparatus for in sity measurement of stress of the film prepared by sputtering using an optical noncontact displacement detector. A Change of the gap distance between the detector and the substrate, caused by stress of a deposited film, was detected by a corresponding change of the reflectivity. The sensitivity of the displacement detector was $5.9\;{\mu}V/{\AA}$ and thus, it was turned out to be good enough to detect stress caused by deposition of a monoatomic layer. The apparatus was applied to in situ stress measurements of Co/X(X=Pd or Pt) multilayer thin films prepared on the glass substrates by dc magnetron sputtering. At the very beginning of the deposition, both Co and X sublayers have subjected to their own intrinsic stresses. However, when the film was thicker than about $100{\AA}$, constant tensile stress in the Co sublayer and compressive stress in the X sublayer were observed, which is believed to be related to a lattice mismatch between the matching planes of Co and X.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1991년도 춘계연구발표회 논문개요집
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• pp.103-104
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• 1991

• 한국자기학회지
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• 제3권4호
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• pp.269-276
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• 1993

Co/Pd 다층박막에서 두 sublayer의 층수비($n_{Co}/n_{Pd}$ = 1/4, 2/4, 3/4, 5/4), 기판온도 ($실온,\;100,\;150,\;200\;^{\circ}C$)를 달리하는 시료를 열진공 증착방법으로 제작하고 이에 대한 Hall 이력곡선을 측정하였다. 이때 나타나는 다야한 형태의 이력곡선을 Co와 Pd sublayer의 자화에 의한 transverse Hall effect 항과 magnetoresistivity 항이 중첩된 것으로 보고 이를 최적 fiting 방법으로 분해하였다. 이 결과 시료 전체의 계면 영역에 걸쳐 강자성과 반강자성인 두 자화상태가 공존하며 이들의 exchange anisotropy의 크기와 반강자성 물질에 의한 강자성 물질의 자벽 고착 효과에 따라 uniaxal 또는 unidirectional easy axis 형의 Hall 이력곡선을 형성하는 것으로 나타났다.

• Journal of Mechanical Science and Technology
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• 제16권2호
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• pp.246-254
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• 2002

Recent primary concern for the design of high performance heat exchanger and highly integrated electronic equipments is to develop an active and creative technologies which enhance the heat transfer without obstructing the coolant flows. In this study, we found through the LDV measurement that the gaseous cavitation induced by ultrasonic vibration applied to the CO$_2$saturated water in the square cross-sectioned straight duct flow enhances the turbulence much more than the case of non-ultrasonic or normal ultrasonic conditions without gaseous cavitation does. We also found that gaseous cavitation can enhance effectively the turbulent heat transfer between the heating surfaces and coolants by destructing the viscous sublayer.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1991년도 추계연구발표회 논문개요집
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• pp.96-97
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• 1991

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2007년도 The 1st International Symposium on Advanced Magnetic Materials
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• pp.74.2-74.2
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• 2007

• 전기전자학회논문지
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• 제13권4호
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• pp.57-62
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• 2009

본 논문에서는 10GBASE-R 형식의 PCS (Physical Coding Sublayer) 구현을 위한 회로로써 표준 속도인 156.25MHz에서 동작하면서 2단 파이프라인 구조로 64b/66b 인코더/디코더를 설계하여 가능한 클록 지연을 최소화한 회로를 제시한다. 제안하는 PCS 회로는 Verilog 하드웨어 설계 언어를 기반으로 설계하여 FPGA를 통한 기능 검증을 위해 Xilinx사의 VertexII-1000fg456 칩에서 측정하였다. 측정한 게이트 수는 47,303이고, Vcc 3.3V에서 351mW의 전력 소모를 보였다.