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환경신뢰성이 확보된 투명전도성 필름을 위한 비공유 결합에 의한 단일벽 탄소나노튜브의 $TiO_2$ 코팅 (Noncovalent Titania Wrapping of Single-Walled Carbon Nanotubes for Environmentally Stable Transparent Conductive Thin Films)

  • 한중탁;김준석;정희진;정승열;이건웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.279-279
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    • 2010
  • We present a simple process for the fabrication of high performance transparent conducting films that contain single-walled carbon nanotubes (SWCNTs) noncovalently coated with an ultrathin titania layer. The hydrophobic interactions between nanotube surfaces and the acetylacetone (acac) ligands used to stabilize the $TiO_2$ precursor provide an interesting alternative method for noncovalently coating the SWCNTs with a titania layer. The ultrathin titania layer on SWCNTs prevented the oxidation of functionalized SWCNTs at high temperatures, and protected against water molecule absorption.

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$TiO_2$ 도입에 따른 ZnO 졸에서의 단일벽 탄소나노튜브의 분산안정성 및 그 투명전도성 필름의 고온 안정성 (Titania-assisted dispersion of carboxylated single-walled carbon nanotubes in ZnO sol for transprent conducting films with high thermal stability)

  • 김보경;한중탁;;정희진;정승열;이건웅
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 춘계학술대회 논문집
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    • pp.41-41
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    • 2010
  • We present facile chemical route stabilizing dispersion of carboxylated single-walled carbon nanotubes (SWCNTs) in ZnOsol prepared by using diethanolamine as a stabilizer. The dispersion was stabilized via capping of carboxyl groups on the SWCNT surface by a titania layer. We also demonstrated that the conductivity of the films prepared P3/$TiO_2$/ZnO as enhanced by therml treatment, and thethermal stbility of the film improved hybridization with ZnO sol pristine P3, P3/$SiO_2$ and P3/$TiO_2$ hybrid films.

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Photocurrent of CdSe nanocrystals on singlewalled carbon nanotube-field effect transistor

  • Jeong, Seung-Yol;Lim, Seung-Chu;Lee, Young-Hee
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 춘계학술대회 논문집
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    • pp.40-40
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    • 2010
  • CdSe nanocrystals (NCs) have been decorated on singlewalled carbon nanotubes (SWCNTs) by combining a method of chemically modified substrate along with gate-bias control. CdSe/ZnS core/shell quantum dots were negatively charged by adding mercaptoacetic acid (MAA). The silicon oxide substrate was decorated by octadecyltrichlorosilane (OTS) and converted to hydrophobic surface. The negatively charged CdSe NCs were adsorbed on the SWCNT surface by applying the negative gate bias. The selective adsorption of CdSe quantum dots on SWCNTs was confirmed by confocal laser scanning microscope. The measured photocurrent clearly demonstrates that CdSe NCs decorated SWCNT can be used for photodetector and solar cell that are operable over a wide range of wavelengths.

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Implementation of OSEK/VDX for Automotive Body Control System

  • Kim, Kee-Woong;Kim, Tae-Yol;Kim, Jae-Goo;Lim, Hong-Joon;Ryu, Syeh-Yung;Lee, Suk
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.178.2-178
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    • 2001
  • Today, many electronic devices and ECUs (Electronic Control Units) are used in the automotive body control systems. It becomes more common that these devices exchange data with others through an in-vehicle network. Automobile manufacturers concentrate their efforts on development of body control systems based on networks in order to save cost and to increase flexibility and safety. OSEK/VDX has been founded as a joint project in German and French automotive industry aiming at an industry standard for an open-ended architecture for distributed control units in vehicles OSEK/VDX consists of Communication (specification of data exchange within and between control units), Network Management specification of Configuration determination and monitoring and Operating System (specification of realtime executive for ECU software ...

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Energy Calibration for Neutron Capture Resonance of Natural Sm by Using 46-MeV Electron Linear Accelerator

  • Lee, Jae-Hong;Lee, Sam-Yol
    • 한국방사선학회논문지
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    • 제1권2호
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    • pp.31-35
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    • 2007
  • Energy calibration is important to identify accurate neutron capture resonance energy in the neutron TOF (Time-of-Flight) experiment. In present study, the accurate neutron capture resonance energies of natural Sm were measured by using a 46-MeV electron linear accelerator (linac) at the Research Reactor Institute, Kyoto University(KURRI). The BGO spectrometer were adopted for measurement the prompt capture gamma-ray of the sample. To obtain energy calibration curve, resonance energy of a gold sample used as standard resonance energy Mughabghab's data (From neutron resonance parameters data). Previous data (by Mughabghab) of natural Sm sample have been compared with the present result.

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Rapid Manufacturing of Microscale Thin-walled Structures using a Phase Change Work-holding Method

  • Shin Bo-Sung;Yang Dong-Yol
    • International Journal of Precision Engineering and Manufacturing
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    • 제7권3호
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    • pp.47-50
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    • 2006
  • High-speed machining is a very useful tool and one of the most effective rapid manufacturing processes. This study sought to produce various high-speed machining materials with excellent quality and dimensional accuracy. However, high-speed machining is not suitable for microscale thin-walled structures because the structure stiffness lacks the ability to resist the cutting force. This paper proposes a new method that is able to rapidly produce very thin-walled structures. This method consists of high-speed machining followed by filling. A strong work-holding force results from the solidification of the filling materials. Low-melting point metal alloys are used to minimize the thermal effects during phase changes and to hold the arbitrarily shaped thin-walled structures quickly during the high-speed machining. We demonstrate some applications, such as thin-walled cylinders and hemispherical shells, to verify the usefulness of this method and compare the analyzed dimensional accuracy of typical parts of the structures.

형상 충전 기법을 이용한 자유표면의 비정상 점성 유동장의 유한 요소 해석 (Finite Element Analysis of Transient Viscous Flow with Free Surface using Filling Pattern Technique)

  • 김기돈;정준호;양동열
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 추계학술대회논문집B
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    • pp.551-556
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    • 2001
  • The filling pattern technique based on the finite element method and Eulerian mesh advancement approach has been developed to analyze incompressible transient viscous flow with free surfaces. The governing equation for flow analysis is Navier-Stokes equation including inertia and gravity effects. The penalty and predictor-corrector methods are used effectively for finite element formulation. The flow front surface and the volume inflow rate are calculated using the filling pattern technique to select an adequate pattern among four filling patterns at each triangular control volume. Using the proposed numerical technique, the collapse of a dam has been analyzed to predict flow phenomenon of fluid and the predicted front positions versus time have been compared with the reported experimental result.

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트러스형 금속 샌드위치 판재에서 심재의 전단특성계수의 실험적 결정 (Experimental Investigation of Shear Modulus of a Core in a Metallic Sandwich Plate with a Truss Core)

  • 정창균;성대용;양동열;문경제;안동규
    • 한국정밀공학회지
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    • 제24권8호통권197호
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    • pp.67-73
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    • 2007
  • A sandwich plate with a truss core is composed of two face sheets and a pyramidal truss core between face sheets. This paper shows how to estimate the shear modulus of a truss core, experimentally. To determine the shear modulus of truss cores, 3-point bending tests are performed. For tests, metallic sandwich beams with truss cores are fabricated. Two kinds of truss cores are tested to investigate the shear modulus. Each test is repeated under different widths in order to increase accuracy. As a result, the shear modulus of sandwich beam is properly calculated. The deflection of a sandwich beam with a truss core by shear deformation takes the major contribution of the total deflection and the shear modulus of sandwich beam should be considered whenever it is designed.

감각신경성 난청의 예후 인자에 대한 평가와 침구 치료에 대한 임상적 고찰 (The Assessments of Prognotic Factors on Sensorineural Hearing Loss And The Clinical Study with Acupuncture Treatment)

  • 문경숙;이소열;권오섭;장조웅;권혁성;윤대환
    • Korean Journal of Acupuncture
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    • 제23권4호
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    • pp.101-110
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    • 2006
  • Objectives : The purpose of this study was clinical observation about sensorineural hearing loss compare with acupucture treatment and assessments of prognotic factors. Methods : This study was clinical observation about sensorineural hearing loss cases. for diagnosing in these cases, pure tone audiometry was used. The treatment, acupuncture was used. Results : Three patients(37.5%) remarkably improved, one patient(12.5%), slightly improved, four patients(50%), no change. Conclusions : These results suggest that the prognosis by age and initial hearing threshold was significant. The treatment on sensorineural hearing loss considered that bone condution improved.

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2차원 연속 Scanning을 이용한 진동모드 해석 (The Analysis of Mode Shape using 2 Dimensional Continuous Scanning)

  • 윤상열;류제길;박기환
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 춘계학술대회논문집
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    • pp.531-535
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    • 2000
  • If the displacement of the structure is obtained by integrating the signal from accelorometer and laser, the vibration mode can be examined. This conventional method, however, has the disadvantage of the necessity of multiple accelerometers and many data processing steps such as frequency response function(FRF). In order to get smooth mode shape, we should also use algorithms of cubic spline or others. In this paper, we propose a method which gets the mode shape by using the velocity signal directly obtained from the plane scanning. In this method, we just use coefficients and phases for specific frequency.

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