• Title/Summary/Keyword: Material parameters

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Surface Characteristics and Photoelectrochemical Properties of the Polyphridine LB films (폴리피리딘계 LB 단분자막의 표면측정과 전기화학적 감광특성)

  • 최인희;나재진;임기조;박수길;이주성
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1995.05a
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    • pp.132-135
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    • 1995
  • This paper describes the electrochemical and photochemical behavior of amphiphilic Os bipyridine compelx adsorbed on SnO$_2$electrodes by the Langmuir-Blodgett(LB) film as monolayer state. Theoretical equation of cyclicvoltammetry for redox species were discussed. And the cyclic voltammogram were simulated taking account theinteraction parameters. From these obtained values, we could fit almost all measured voltammograms with these parameters.

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Optimum Design Study on 0.5 MJ-Class Superconducting Pulse Magnet (0.5MJ 초전도 펄스 마그네트의 최적화 설계에 관한 연구)

  • 노완수;한송엽;황석영;이승원;홍원표
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.39 no.8
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    • pp.813-819
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    • 1990
  • In this paper, a new design method for superconducting pulse magnet is presented. Given energy storage capacity, magnet shape parameters are determined to minimize superconducting material quantity. Once the shape parameters are determined, cooling channel is designed and degradation characteristics are confirmed. According to the proposed magnet design concept, relatively uniform and low field distribution is obtained. Therefore, both the quantity of superconducting material and the mechanical load over magnet are reduced.

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Electrical and Optical Properties of ITO Thin Film by CMP Process Parameter (CMP 공정이 ITO 박막의 전기적.광학적 특성에 미치는 영향)

  • Choi, Gwon-Woo;Seo, Yong-Jin;Lee, Woo-Sun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.11a
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    • pp.354-355
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    • 2005
  • Indium tin oxide (ITO) thin film was polished by chemical mechanical polishing (CMP) by the change of process parameters for the improvement of electrical and optical properties of ITO thin film. Light transparent efficiency of ITO thin film was improved after CMP process at the optimized process parameters compared to that before CMP process.

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Experimental and Numerical Study on Anisotropic Phase Separation of Liquid Crystal and Polymer Composites Cell Gap Variation

  • Jin, Min-Young;Bae, Ji-Hong;Kim, Jae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08a
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    • pp.567-570
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    • 2007
  • Cell gap dependence on anisotropic phase separation was studied. The results showed that the morphology of phase separation depended on cell gap and material parameters. With numerical simulation and experiments, the optimal range of cell gap in the formation of polymer layer and liquid crystal was suggested for given material parameters.

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Design and simulation of the DR ceramic bandpass filter for WLL(Wireless Local Loop) basestation (WLL(Wireless Local Loop) 기지국용 DR(Dielectric Resonator) 세라믹 대역통과 필터 설계와 시뮬레이션)

  • 김지균;이헌용
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.315-318
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    • 1999
  • The purpose of this study is to establish the design theory of a DR ceramic bandpass filter used for WLL basestations and to research on the design theory of bandpass filter. The design procedure is circuit parameters and structural parameters will be derived. It was observed that the filter characteristics at the simulations

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A study on the Discharge Characteristics of Facing Targets Sputtering Systems and Fabrications of $Al_{N}$ Thin Films (대향전극 스파트링 시스템의 방전특성과 $Al_{N}$ 박막형성에 관한 연구)

  • 이종호;이규철;남용수;김경석
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1994.05a
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    • pp.71-73
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    • 1994
  • In this paper we have investigated discharge conditions(parameters of this experiment) in facing targets sputtering system and fabricated $Al_{N}$ thin films. The parameters of this study are diameter of wing(d) and distance(L) between two facing targets. Varing discharge conditions, the discharge characteristics are wide different. The optimal conditions in this experiments are d = 6.5 [cm], L = 6.5[cm]

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Thin Oxide Functional Films by Metal Alkoxide Method

  • Natalya, Korobova
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.9-16
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    • 2000
  • A survey over the role of sol-gel processing and metal alkoxides in the thin film preparation is given. The basic chemistry of the sol-gel process is complex due to the different reactivities of the network forming and the wide variety of reaction parameters. Despite the important progress in the investigations of the mechanisms of thin film formation, a direct relation of reaction parameters to functional oxide properties is still very difficult.

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Data driven inverse stochastic models for fiber reinforced concrete

  • Kozar, Ivica;Bede, Natalija;Bogdanic, Anton;Mrakovcic, Silvija
    • Coupled systems mechanics
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    • v.10 no.6
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    • pp.509-520
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    • 2021
  • Fiber-reinforced concrete (FRC) is a composite material where small fibers made from steel or polypropylene or similar material are embedded into concrete matrix. In a material model each constituent should be adequately described, especially the interface between the matrix and fibers that is determined with the 'bond-slip' law. 'Bond-slip' law describes relation between the force in a fiber and its displacement. Bond-slip relation is usually obtained from tension laboratory experiments where a fiber is pulled out from a matrix (concrete) block. However, theoretically bond-slip relation could be determined from bending experiments since in bending the fibers in FRC get pulled-out from the concrete matrix. We have performed specially designed laboratory experiments of three-point beam bending with an intention of using experimental data for determination of material parameters. In addition, we have formulated simple layered model for description of the behavior of beams in the three-point bending test. It is not possible to use this 'forward' beam model for extraction of material parameters so an inverse model has been devised. This model is a basis for formulation of an inverse model that could be used for parameter extraction from laboratory tests. The key assumption in the developed inverse solution procedure is that some values in the formulation are known and comprised in the experimental data. The procedure includes measured data and its derivative, the formulation is nonlinear and solution is obtained from an iterative procedure. The proposed method is numerically validated in the example at the end of the paper and it is demonstrated that material parameters could be successfully recovered from measured data.

A Study of Material Removal Characteristics by Friction Monitoring System of Sapphire Wafer in Single Side DMP (사파이어 웨이퍼 DMP에서 마찰력 모니터링을 통한 재료 제거 특성에 관한 연구)

  • Jo, Wonseok;Lee, Sangjik;Kim, Hyoungjae;Lee, Taekyung;Lee, Seongbeom
    • Tribology and Lubricants
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    • v.32 no.2
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    • pp.56-60
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    • 2016
  • Sapphire has a high hardness and strength and chemical stability as a superior material. It is used mainly as a material for a semiconductor as well as LED. Recently, the cover glass industry used by a sapphire is getting a lot of attention. The sapphire substrate is manufactured through ingot sawing, lapping, diamond mechanical polishing (DMP) and chemical mechanical polishing (CMP) process. DMP is an important process to ensure the surface quality of several nm for CMP process as well as to determine the final form accuracy of the substrate. In DMP process, the material removal is achieved by using the mechanical energy of the relative motion to each other in the state that the diamond slurry is disposed between the sapphire substrate and the polishing platen. The polishing platen is one of the most important factors that determine the material removal characteristics in DMP. Especially, it is known that the geometric characteristics of the polishing platen affects the material removal amount and its distribution. This paper investigated the material removal characteristics and the effects of the polishing platen groove in sapphire DMP. The experiments were preliminarily carried out to evaluate the sapphire material removal characteristics according to process parameters such as pressure, relative velocity and so on. In the experiment, the monitoring apparatus was applied to analyze process phenomena in accordance with the processing conditions. From the experimental results, the correlation was analyzed among process parameters, polishing phenomena and the material removal characteristics. The material removal equation based on phenomenological factors could be derived. And the experiment was followed to investigate the effects of platen groove on material removal characteristics.

Static and Dynamic FEM Simulation of Packaging Tray Cup Pad for Korean Pears

  • Choi, Dong-Soo;Son, Jea-Yong;Kim, Jin-Se;Kim, Yong-Hoon;Park, Chun-Wan;Jung, Hyun-Mo;Hwang, Sung-Wook
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.25 no.3
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    • pp.89-94
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    • 2019
  • Among the many packaging materials used in cushion packaging, there is a lack of optimum design for the tray cup pad used in fruit packaging for export and domestic distribution. It causes over-packaging due to excessive material input, and this could be solved by applying various parameters needed to optimize the design of the tray cup pad considering the packaging material and the quantity of fruits in the box. In the case of a tray cup for fruits, the economic efficiency of material and thickness should be considered. Therefore, it is possible to design a tray cup pad depending on the packaging material used by applying appropriate design parameters. The static and dynamic characteristics of the materials used for packaging of pears were analyzed by using the FEM (finite element Method) simulation technique to derive the optimal design parameters. And by applying the appropriate design parameters considering the quantity of fruit and distribution environment, it is possible to design an appropriate fruit tray cup pad. In this study, as a result of simulating the contact stresses between the fruit and the tray cup for the PP, PE, and PS materials used in the fruit tray cup, the material with the lowest contact stress was PP and the value was found to be 398 Pa. The contact displacement between fruit and tray cup using this material was about 0.0463 mm, which was the lowest value compared with other materials. Also the resonance frequency band of tray cup made of PP material was below 36.81 Hz, and the strain energy was below 12.20 J. The resonant frequency band of the pear is more than 80 Hz and it could be applied to all the tray cup materials as compared with the resonance band of 38.81 Hz or less which is the resonance band of all tray cup pads for packaging. Finally, PP is the most suitable material for the tray cup pad.