• 제목/요약/키워드: pulling

검색결과 473건 처리시간 0.019초

$LiNbO_3$단결정성장 및 특성 연구 (Growth And Characterization of $LiNbO_3$ Single Crystals)

  • 손진영;노광수;이진형
    • 한국결정성장학회지
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    • 제2권1호
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    • pp.43-50
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    • 1992
  • 인상속도를 변수로 Czochralski법을 이용하여 $ LiNbO_3$결정들을 성장시켰다. 성장된 단결정에 균열, 기포, 셀 구조 등의 결함들이 관찰되었다. 균열들은 인상속도와 냉각속도에 매우 민감하였는데 6~7mm/h의 인상속도와 20^{circ}C/h의 냉각속도가 직경 15mm정도의 결정성장에 적당한 조건임을 알 수 있었다. 소자응용에 필요한 유전적 성질 및 광학적 성질 등을 알아보기 위하여 a축, c축방향에 따라 절삭된 시편을 온도를 변화시켜가며 측정하였다.

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Changes of Pulling-out Length and Shrinkage Ratio in Polyester/Spandex Power Net Warp Knitted Fabrics

  • Lee Choon-Gil
    • Fibers and Polymers
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    • 제7권1호
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    • pp.51-56
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    • 2006
  • Power net fabric is one of the highly extensible two-way fabrics. Power net structure shows special characteristics in the wearing of final functional clothes. This research evaluated effects of treatment temperature on proportional extensibility and shrinkage ratio of spandex at a given wale length. As treatment temperature increased, extensibility increased proportionally to the standard length of the sample and the shrinkage ratio in the direction of course and wale increased. The pulling-out length increased proportionally to the standard length of the sample. However it was affected by the effect of treatment time and temperature due to the thermal properties of spandex filament yarn.

MICROSTRUCTURE AND HIGH TEMPERATURE MECHANICAL PROPERTIES OF SAPPHIRE/R-Al-O (R=Y,Gd,Er,Ho,Dy) EUTECTIC FIRES GROWN BY MICRO PULLING-DOWN METHOD

  • Hasegawa, K.;Yoshikawa, A.;Durbin, S.;Epelbaum, B.;Fjkuda, T.;Waku, Y.
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1999년도 PROCEEDINGS OF 99 INTERNATIONAL CONFERENCE OF THE KACG AND 6TH KOREA·JAPAN EMG SYMPOSIUM (ELECTRONIC MATERIALS GROWTH SYMPOSIUM), HANYANG UNIVERSITY, SEOUL, 06월 09일 JUNE 1999
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    • pp.403-418
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    • 1999
  • Fiber growth of Al2O3/R-Al-O(R=Y, Gd, Dy, Ho, Er) eutectic by the micro-pulling down methods is described. The thermal stability and strength at elevated temperature of each material is evaluated in relation to the microstructure. PACS: 81.05 Mh, 81.10 Fq, 81.30-t.

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TSSG-pulling of Sillenite $Bi_{12}TiO_{20}$ for EOS Application

  • Miyazawa, Shintaro
    • 한국결정성장학회:학술대회논문집
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    • 한국결정성장학회 1999년도 PROCEEDINGS OF 99 INTERNATIONAL CONFERENCE OF THE KACG AND 6TH KOREA·JAPAN EMG SYMPOSIUM (ELECTRONIC MATERIALS GROWTH SYMPOSIUM), HANYANG UNIVERSITY, SEOUL, 06월 09일 JUNE 1999
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    • pp.227-250
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    • 1999
  • The reproducibility of successive growth of Bi12TiO20(BTO) single crystals using a top-seeded solution growth (TSSG) pulling method was evaluated by measuring the lattice constants and their standard deviations. A substantial phase diagram in the region close to the stoichiometric BTO was established experimentally for this purpose, and the existence of a retrograde solid solution close to a BTO was clarified. It was emphasize that a starting solution, with a 10.0~10.1 mol% TiO2 concentration, results in large single crystals with a highly homogeneous lattice constant of within $\pm$1x10-4$\AA$, when the solidified fraction of the grown crystal is less than about 45%. A wavelength dispersion of refractive index was measured for the first time, an it was verified that the refractive index of BTO is larger than that of BSO(Bi12TiO20), allowing the voltage sensitivity of EOS higher than the case with BSO as a probe head.

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초크랄스키법에 의한 실리콘 단결정성장에서 회전효과가 미치는 영향에 대한 연구 (Effects of Rotation on the Czochralski Silicon Single Crystal Growth)

  • 김무근
    • 대한기계학회논문집
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    • 제19권5호
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    • pp.1308-1318
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    • 1995
  • The influence of varying rotation speed of both crystal and crucible was numerically investigated for the Czochralski silicon-crystal growth. Based on a simplified model assuming flatness of free surfrae, the Navier-Stokes Boussinesq equations were employed to identify the flow pattern, temperature distribution as well as the shape of the melt/crystal interface. The present results showed that the interface shape was relatively convex with respect to the melt at lower pulling rate and tended to be concave as the pulling rate increased. In particular, the experimentally observed gull-winged shape of the interface was qualitatively in agreement with the predicted shape. The rotation of crystal alone little affected the growth system. When the rotation speed of the crucible was increased, there occurred inversion of the interface shape from convex to concave pattern. At rapid rotation of the crucible, an interesting channel formation was predictied primarily due to the assumption of laminar flow.

깊은 홈 및 절단가공용 드로우어웨이식 초경공구 시스템의 설계에 관한 연구 (A Study on the Design of Throw-away Cutting Tool System for Deep Grooving or Cut-off Machining)

  • 김형철;이우영;남궁석
    • 한국정밀공학회지
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    • 제13권1호
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    • pp.123-130
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    • 1996
  • The procedure on the design of a new tungsten cabide throw-away cutting tool system for deep grooving or cut-off machining is suggested. For relieving the maximum stress level at the corner radius of the blade holder, the finite element method is used. Also the pulling test device is proposed for measuring the holding force of the insert between the blade holder and the insert considering the materials in contact and configuration parameters of the holder.

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보행형 인발식 마늘수확기 개발 (Development of a Walking Garlic Harvester with Pulling Mechanism)

  • 노광모;장영창;박준걸;용상호
    • Journal of Biosystems Engineering
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    • 제27권6호
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    • pp.513-520
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    • 2002
  • A 5-row walking garlic harvester with pulling mechanism was developed in the study, based upon a kinematical analysis and related preliminary field tests on the conventional garlic harvesting method. The harvesting efficiency of the developed harvester was more than 98% in the garlic field irrigated before harvesting, 80-85% in the field without irrigation. The harvesting performance of the harvester was 660∼825㎡/hr at the forward speed of harvester of 0.3m/s in the irrigated field before garlic harvesting. For proper garlic drying and collection, the harvester discharged the harvested garlic on the ground uniformly at the angles of 135。∼150。 to its forward direction with the garlic bulb's placing toward the harvester. In the field tests, it was recommended that the forward speed of the harvester be approximately less than 0.2m/s, and that the spacing of planting garlic seeds should be standardized in the future fur increasing its harvesting efficiency.

힘센서를 이용한 후크형 손가락 힘 측정 장치 개발 (Development of a Hook-type Finger Force Measuring System with Force Sensors)

  • 김갑순
    • 제어로봇시스템학회논문지
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    • 제20권6호
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    • pp.663-668
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    • 2014
  • This paper presents a hook-type finger force measuring system with force sensors. The system is composed of a body, two three-axis force sensors, a hook, and so on. The two three-axis force sensors system was specially designed using FEM(Finite Element Method) and fabricated using strain-gages. The sensors measure the finger forces of both normal people and handicapped people in the system, and the forces are combined. The developed hook-type finger force measuring system can measure the pulling finger force of both normal and handicapped people. The pulling force tests of men and women were performed using the developed the system. It is thought that the developed system can be used to measure the pulling force of fingers.

Potential of Mean Force Simulation by Pulling a DNA Aptamer in Complex with Thrombin

  • Yang, Changwon;Kim, Eunae;Pak, Youngshang
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3597-3600
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    • 2012
  • Thrombin binding aptamter (TBA-15) is a 15-mer guanine-rich oligonucleotide. This DNA apamer specifically binds to the thrombin protein involved in blood coagulation. Using extensive umbrella sampling molecular dynamics simulation method at all atom level, we investigated the potential of mean force (PMF) upon pulling the DNA aptamer from the binding mode of aptamer/thrombin complex. From this calculation, the free energy cost for a full dissociation of this aptamer/protein complex is 17 kcal/mol, indicating a substantial binding affinity of TBA-15. Interestingly, this PMF reveals noticeable plateau regions along the pulling coordinate. Possible structural changes of this complex in the plateau were investigated in details.

표면 분석을 이용한 컴퓨터 하드디스크용 윤활제의 특성 연구 (Investigation of the Characteristics of Lubricant in Computer Hard Disk by Using Surface Analysis Technique)

  • 조남철;남인탁
    • 한국자기학회지
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    • 제9권5호
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    • pp.263-270
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    • 1999
  • 컴퓨터 하드디스크용 윤활제인 PFPE중 Z-DOL과 AM2001을 이용하여 pulling-up speed와 윤활제의 농도를 변화시키면서 윤활제의 두께변화를 알아보았으며, 또한 열처리를 통해 overcoat층인 carbon과 윤활제의 결합특성을 알아보았다. Pulling-up speed가 빠를수록, 그리고 윤활제의 농도가 증가할수록 윤활제의 두께는 두껍게 coating되었음을 알 수 있었으며, 또한 XPS을 이용하여 분석해 본 결과, overcoat층인 carbon에 존재하는 표면 오염물은 C-OH, CO가 지배적이었고, 열처리를 함으로써 overcoat층인 carbon과 윤활제의 결합력이 증진됨을 알 수 있었다.

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