• Title/Summary/Keyword: In-situ

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Coarsening Behavior of Fine Precipitates in Rapidly Quenched Al-Fe Based Alloy Ribbons by In-situ Heat Treatment (급랭응고한 Al-Fe 합금계 리본을 고온에 노출시킴에 따른 미세석출물의 성장거동)

  • Baik, Nam-Ik
    • Journal of Korea Foundry Society
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    • v.15 no.3
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    • pp.252-261
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    • 1995
  • The purposes of this study were to investigate the microstructural changes in alloy ribbons of Al-Fe-Mo-Si quarternary system at $450{\sim}500^{\circ}C$, and to study the coarsening mechanism of fine precipitates. Using the hot stage in TEM, in situ microstructural changes in Al-4Fe-0.5Mo-1.5Si alloy ribbon and Al-8Fe-2Mo-1.5Si alloy ribbon have been examined successively up to 60 hours at $450^{\circ}C$ and $500^{\circ}C$. Cell structure in zone B of Al-4Fe-0.5Mo-1.5Si alloy ribbon was observed to collapse even in 10 minutes by in-situ heating at $450^{\circ}C$ and the size of precipitates in zone B increased twice in 60 hours. The precipitates in zone A of Al-4Fe-0.5Mo-1.5Si alloy ribbon showed slower coarsening rate than those in zone B by in-situ heating at $450^{\circ}C$. The precipitates in zone A of Al-8Fe-2Mo-1.5Si alloy ribbon increased 50% by in-situ heating at $500^{\circ}C$ in 50 hours compared to the initial precipitates while any microstructual change in zone B was not observed by in-situ heating at $500^{\circ}C$ up to 50 hours. Only the precipitates in zone A of Al-4Fe-0.5Mo-1.5Si alloy ribbon satisfied $r^3{\propto}t$ relationship of coarsening mechanism.

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보급형 He-Ne 타원해석기의 제작과 $TiO_2$ 박막 유효밀도 변화의 in situ 측정

  • 김상준;방현용;김상열
    • Proceedings of the Korean Vacuum Society Conference
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    • 1999.07a
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    • pp.101-101
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    • 1999
  • 실시간으로 변화하는 시료를 측정하고 분석할 수 있도록 비접촉시이며, 광학방식인 단파장 in situ 타원해석기를 제작하였다. He-Ne 레이저를 광원으로 사용하였고 회전편광자형 광량 측정방식을 채택하였다. 기존의 진공챔버 등에 쉽게 장착할 수 있도록 동축 구조를 사용하였으므로 소형이며 단순한 설계가 가능하였다. 전자빔 증착방법으로 성장시킨 조밀도가 82%인 이산화티타늄 박막의 분석에 이 타원해석기를 사용하여 수분탈착에 따르는 이산화티타늄 박막의 유효밀도 변화를 박막의 온도 변화와 시간 변화에 따라 실시간 in, situ방식으로 관측하였다.

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Optimum Growth Condition of Phase Change GeSbTe Thin Films as an Optical Recording Medium using in situ Ellipsometry (In situ 타원법을 사용한 광기록매체용 GeSbTe 박막의 최적성장조건 연구)

  • 이학철;김상열
    • Proceedings of the Optical Society of Korea Conference
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    • 2003.02a
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    • pp.78-79
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    • 2003
  • 타원법(ellipsometry)을 사용하여 광기록 매체용 Ge$_2$Sb$_2$Te/sub 5/(GST) 박막의 성장과정에 따른 타원상수 Ψ와 $\Delta$를 측정하여, GST 박막의 최적성장조건을 연구하였다. 아르곤기체압력과 DC 출력 그리고 기판의 온도를 변화시키면서 GST 박막을 성장시켰다. 제작된 시료들의 분광타원 데이터를 모델링분석하여 GST 박막의 밀도분포를 구하고 한편으로는 GST 박막이 성장하는 동안 측정한 in situ 타원 성장곡선을 분석하여 박막의 밀도분포의 변화를 추적하였다. (중략)

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In Situ Rescue Bypass for Iatrogenic Avulsion of Parent Artery during Clipping Large Pericallosal Artery Aneurysm

  • Park, Jae-Chan;Kang, Dong-Hun
    • Journal of Korean Neurosurgical Society
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    • v.46 no.1
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    • pp.68-70
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    • 2009
  • A case of large aneurysm arising from the distal end of an azygous A2 segment is presented. Multiple clip application inadvertently tore the aneurysmal neck, resulting in near avulsion of a right pericallosal artery origin. After an unsuccessful attempt to repair the avulsion, it was treated by occlusion of the origin of the pericallosal artery and an A4-A4 anterior cerebral artery in situ bypass without neurological deficits. The surgical technique and previous reports onside-to-side in situ bypass are discussed.

In-situ monitoring technique for deposition process of CdS buffer layer for CIGS thin film solar cells (CIGS 박막 태양전지용 CdS 버퍼층 제조 공정의 in-situ 모니터링 기술)

  • Kown, Young-Jun;Ahn, Se-Jin;Yoon, Jae-Ho;Yoon, Kyung-Hoon
    • 한국신재생에너지학회:학술대회논문집
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    • 2008.05a
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    • pp.434-435
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    • 2008
  • An in-situ monitoring technique for deposition process of CdS buffer layer was developed in this work. A quartz crystal microbalance (QCM) was used to measure the frequency change during the CdS deposition process and the relation ship between frequency change and film thickness and optical transmittance was investigated. The film thickness shows a linear relationship with frequency change, demonstrating that frequency change measured by QCM can be used a in-situ monitoring tool for CdS deposition process.

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In Situ Saphenous Vein Arterial Bypass - A case report - (자연위치의 복재정맥을 이용한 하지동맥 우회술 1례 보)

  • Lee, Hong-Seop;Park, Guk-Yang;Kim, Chang-Ho
    • Journal of Chest Surgery
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    • v.20 no.1
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    • pp.187-190
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    • 1987
  • The Saphenous vein is still the graft of choice for bypass of small calibered peripheral arteries, and many recent studies revealed that the "In Situ" technique had higher rate of long term patency than the conventional "reversed" one. A 71-year-old male who had atherosclerotic obstruction in the superficial femoral and popliteal trifurcation underwent In Situ saphenous vein arterial bypass. The saphenous vein is exposed by a long medial skin incision over the course of the vein. All branches of vein are ligated. A olive-tipped metal needle is introduced into the vein from above and everts the valves. The patient has been followed for 2 months after operation. The graft remained pulsatile and the gangrenous areas on the toe proceeded to heal. We think In situ vein bypass offers an excellent and safe method of revascularization of the arterial occlusion below the knee although it is technically demanding and the time consuming. time consuming.

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A Note on in-Situ Burning of Marine Oil Spills (해상누유 현장소각 기술에 대한 소고)

  • Sung H.G.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.3 no.3
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    • pp.58-65
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    • 2000
  • Responses to marine oil spills can be classified Into categories; 1) mechanical treatment using booms and skimmers, 2) chemical one utilizing dispersants, 3) controlled in-situ burning of spilled oils. In the present paper, characteristics, history, present issues, advantages and disadvanteges, and future applicability of in-situ burning technology which is nowadays winning much attention are summarized on the basis of a survey of related papers and other resources.

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The Improvement Effects of Soft Ground by Quick Lime Pile (생석회파일에 의한 연약지반개량효과)

  • 천병식;고갑수;장은석;임지섭;이용한
    • Proceedings of the KSR Conference
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    • 1999.05a
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    • pp.383-389
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    • 1999
  • This paper is a study on the improvement effects by quick lime pile through theoretical analysis and in-situ construction test. Effects of strength increase is studied to verify the improvement effects of soft ground arounding quick lime pile. First, engineering characteristics of quick lime and ground was studied, in the second place, laboratory test(consolidation test, triaxial compression test) and in-situ test(portable cone penetration test, vane test) were peformed for verification of strength increase of adjacent ground. Finally, the results of in-situ test were compared with those of theorecal study. From in-situ test results, strength at 28th curing days(6.11-6.55t/㎡) was twice as great as strength before improvement(3.06t/㎡) and was slightly greater than theoretical value(4.95t/㎡).

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Study on Compressive Strength of Cast-in-situ Concrete Pile (현장타설 말뚝의 수중부 콘크리트 강도에 대한 고찰)

  • Shim, Jae-Won;Jeon, Kyung-Soo;Kim, Nag-Young;Park, Chan-Min
    • Proceedings of the Korean Geotechical Society Conference
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    • 2009.09a
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    • pp.564-569
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    • 2009
  • Due to the uneasy controllable qualities of the substructures such as pile and foundation, which are laid on underground, geotechnical engineers have applied conservative criteria to them. Therefore, the specification criterion of cast-in-situ concrete pile, which allows only one fourth of the compressive strength of structural capacity, has forced geotechnical designers to consider the most uneconomical design regardless of satisfying the grade of quality-control, required performance, construction cost and so on. Thus, in this study, we proposed the less conservative criteria on the strength of concrete pile, based on the experimental testing results of cast-in-situ concrete piles.

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