• 산업기술연구
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• 제4권
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• pp.55-60
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• 1984

Silicastone of Hongcheon in Kangweon province was characterized by means of chemical analysis, scanning electron microscope, polarization microscope and x-ray diffractometer. The results showed that the purity of $SiO_2$ is over 97.64 in Wt-%. It also contains 0.046-0.417 Wt-% $Fe_2O_3$ and some others as impurity. The impuity exist as a isolated mineral type of hematite, sericite, apatite etc.

• Tribology and Lubricants
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• 제7권2호
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• pp.61-66
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• 1991

The frictional and wear characteristics of non-asbestos friction materials made of four different fibers (carbon, aramid, ceramic and glass) have been investigated at elevated temperature using High Frequency Friction Tester. On the basis of the experimental results, friction and wear phenomena of four different non-asbestos fibers were caused by lattice layer film of carbon, polymeric transfer film of aramid, abrasion of ceramic and adhesion of glass fiber under each contact junction. The surface analysis of the worn specimens and counter parts after tests were observed using Scanning Electron Microscope and Optical Microscope.

• 한국산학기술학회논문지
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• 제9권2호
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• pp.303-310
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• 2008

ICP-CVD(inductively-coupled Plasma chemical vapor deposition)를 사용하여 $250^{\circ}C$기판온도에서 140 nm 두께의 수소화된 비정질 실리콘(${\alpha}$-Si:H)을 제조하였다. 그 위에 30 nm-Ni을 열증착기를 이용하여 성막하고, $200{\sim}500^{\circ}C$ 사이에서 $50^{\circ}C$간격으로 30분간 진공열처리하여 실리사이드화 처리하였다. 완성된 실리사이드의 처리온도에 따른 실리사이드의 면저항값 변화, 미세구조, 상 분석, 표면조도 변화를 각각 사점면저항측정기, HRXRD(high resolution X-ray diffraction), FE-SEM(field emission scanning electron microscope), TEM(transmission electron microscope), SPM(scanning probe microscope)을 활용하여 확인하였다. $300^{\circ}C$에는 고저항상인 $Ni_3Si$, $400^{\circ}C$에서는 중저항상인 $Ni_2Si$, $450^{\circ}C$이상에서 저저항의 나노급 두께의 균일한 NiSi를 확인되었다. SPM결과에서 저저항 상인 NiSi는 $450^{\circ}C$에서 RMS(root mean square) 표면조도 값도 12 nm이하로 전체 공정온도를 $450^{\circ}C$까지 낮추어 유리와 폴리머기판 등 저온기판에 대응하는 저온 니켈모노실리사이드 공정이 가능하였다.

• Mycobiology
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• 제37권1호
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• pp.5-9
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• 2009

An Ophiostoma fungus was isolated from a stump of Pinus thunbergii in a forest on the West coast of Korea. Microscopic analysis using a light microscope, a stereo microscope, and a scanning electron microscope revealed that it had morphological features of Pesotum and Sporothix synanarmorphs. Based on the $\beta$-tubulin gene sequence analysis, the fungus was identified as the anamorph of Ophiostoma floccosum. Mycological properties of the species including its growth properties on different culture media were described.

• KEPCO Journal on Electric Power and Energy
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• 제7권2호
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• pp.237-240
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• 2021

Failure of a suspension clamp made of hot dip galvanized cast iron in 154kV transmission tower was investigated. Metallurgical analysis of a crack of the clamp was performed using a digital microscope, an optical microscope, and a scanning electron microscope. It was revealed that the crack surface was covered by continuous zinc layer. Distinctive casting skin was found underneath both the outer surface and crack surface. The result showed that pre-existing crack had been formed in the fabrication, and liquid metal embrittlement during hot dip galvanization may assist crack propagation.

• 한국표면공학회지
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• 제40권4호
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• pp.185-189
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• 2007

A scanning electron microscope (SEM) is a complex system, consisting of many sophisticated components. For a systematic characterization, a $2^4$ full factorial experiment was conducted. The SEM components examined include condenser lens 1 and 2 (denoted as A and B, respectively), and Objective lens (coarse and fine-denoted as C and D respectively). A statistical analysis was conduced to investigate factor effects and variations In response surfaces. Among four factors, main effect analysis revealed that A and D were Identified as the dominant factor. Moreover, B showed conflicting effect against C. The $R^2$ of statistical regression model constructed was about 69.6%. The model generated 3D response surface plots facilitated understanding of complex tactor effects.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.5-6
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• 2009

In this paper, plasma ion implant is performed with $PH_3$ gas diluted by helium gas on P-type Si wafer (100). Spike Rapid Thermal Processing(RTP) annealing performed for 30~60 sec from $800\;^{\circ}C$ to $1000\;^{\circ}C$ in $N_2+O_2$ ambient. Crystalline defect is analyzed by Transmission Electron Microscope(TEM) and Double crystal X-ray Diffraction(DXRD). Contact resistivity($\rho c$), contact resistance(Rc) and sheet resistance(Rs) are analyzed by measuring Transfer Length Method(TLM) using 4155C analysis. As annealing temperature increase, Rs decrease and ${\rho}c$ and Rc increase at temperature higher than $850\;^{\circ}C$. We achieve low Rs, ${\rho}c$ and Rc with Plasma ion implant and spike RTP.

• 한국광학회:학술대회논문집
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• 한국광학회 2002년도 하계학술발표회
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• pp.162-163
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• 2002

1-D photonic band-gap structure is identified in a cholesteric liquid crystal system. The optical transmission spectrum is measured and compared with the theoretical analysis. Nonlinear transmission is measured near the band edge. Also 3-D photonic band-gap structures are fabricated from dielectric colloidal polystyrene beads through a centrifuge method. The fabricated photonic crystals exhibit opalescent colors under white light and show a clear diffraction peak dependent on the incident angle of the light beam. Also the scanning electron microscope image was taken to verify the face-centered cubic crystal structure. Bragg's law and Snell's law are employed to describe the position of angle resolved diffraction peaks. It was shown that the optically deduced effective refractive index and lattice constants were in good agreement with the crystal structure identified by scanning electron microscope.

• Applied Microscopy
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• 제43권1호
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• pp.9-13
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• 2013

The helium ion microscope (HIM) has recently emerged as a novel tool for imaging and analysis. Based on a bright ion source and small probe, the HIM offers advantages over the conventional field emission scanning electron microscope. The key features of the HIM include (1) high resolution (ca. 0.25 nm), (2) great surface sensitivity, (3) great contrast, (4) large depth-of-field, (5) efficient charge control, (6) reduced specimen damage, and (7) nanomachining capability. Due to the charge neutralization by flood electron beam, there is no need for conductive metal coating for the observation of insulating biological specimens by HIM. There is growing evidence that the HIM has substantial potential for high-resolution imaging of uncoated insulating biological specimens at the nanoscale.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1995년도 봄 학술발표회 논문집
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• pp.164-169
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• 1995

Cracks in the concrete structure are known to develope by various mechani는, including an alkali-aggregate reaction. The alkali-silicate reaction between aggregates and cement is studied using polarized microscope, electron probe microanalyser and electron microscope. Metamorphosed, biaxial quartz and feldspars grains appear to have reacted readily with alkali from cement. For a given mineral, fine-grained minerals tend to react readily over the coarse-grained ones. A chemical analysis shows that the elements K, Na, Ca, and Si migrated, in most cases, fro the portion of h호 concentration to the low, Some clay minerals, including smectite and illite are newly formed as one of the reaction products. The continual expansion and shrinkage of the expandible clay minerals, probably due to repeated absorption and loss of water within the structure, plays an important role in the development of cracks within the concrete structure.