• Title/Summary/Keyword: substrate effect

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Size Effect on the Modulus of Rupture in Automotive Ceramic Monolithic Substrate using Optimization and Response Surface Method (반응표면법과 최적화방법을 이용한 자동차 세라믹 모노리스 담체의 파단계수에 미치는 치수효과)

  • Baek, Seok-Heum;Shin, Soon-Gi;Joo, Won-Sik;Cho, Seok-Swoo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.30 no.11 s.254
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    • pp.1392-1400
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    • 2006
  • Since the monolithic ceramic substrate was in introduced for automotive catalytic converters, the durability of the substrate has been a continuing requirement to reduce the emission, gas of vehicle. The substrate can occupy a volume as small as 82 $cm^3$ and as large as 8200 $cm^3$ to provide the required substrate for catalytic activity. The long-term durability varies with the size of the substrate from manufacture's point of view. Therefore this study presents that the response surface model using central composite design can explain size effect on the modulus of rupture in a cordierite ceramic monolithic substrate.

Effect of Substrate Concentration and Feeding Period Ratio on Sludge Granulation in UASB Process (UASB 공정에서 기질농도 및 기질주입 기간비가 슬러지 입상화에 미치는 영향)

  • 최영근;이헌모
    • Journal of Environmental Science International
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    • v.6 no.2
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    • pp.113-124
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    • 1997
  • The basic mechanism of the granular sludge formation which is the most important factor in the start-up and stable operators is not confirmed yet. In this study, the effect of granular sludge formation was investigated with the different substrate concentrations and the various ratios of substrate supply/deficiency. The granular sludge formation in the UASB reactor was closely related to the substrate concentrations and the ratio of substrate supply/deficlency The granular sludge formation was not accelerated at low substrate concentration. It was convinced that granular sludge formation was accelerated when the substrate supply with high concentration was stopped at UASB reactor. From this experiment, it was estimated that granular sludge was formed by the combination of hydrogen utilizing bacteria that form hydrogen condition and acid forming bacteria at substrate deficit condition by mutual symbiosis. Though the removal efficiency of organic matter was decreased as the influent substrate concentration was Increased, the higher the influent substrate the better the granular sludge formation.

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Effect of substrates on the geometries of as-grown carbon coils

  • Park, Semi;Kim, Sung-Hoon;Kim, Saehyun;Jo, Insu
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2012.11a
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    • pp.163-164
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    • 2012
  • Carbon coils could be synthesized using $C_2H_2/H_2$ as source gases and $SF_6$ as an incorporated additive gas under thermal chemical vapor deposition system. The substrate with oxygen incorporation and the substrate without oxygen incorporation were employed to elucidate the effect of substrate on the formation of carbon coils. The characteristics (formation densities, morphologies, and geometries) of the deposited carbon coils on the substrate were investigated. In case of Si substrate, the microsized carbon coils were dominant on the substrate surface. While, in case of oxygen incorporated substrate, the nanosized carbon coils were prevail on the substrate surface. The cause for the different geometry formation of carbon coils according to the different substrates was discussed in association with the different thermal expansion coefficient values between the substrate with oxygen incorporation and the substrate without oxygen incorporation.

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Molecular Dynamics Study on Behaviors of Liquid Cluster with Shape and Temperature of Nano-Structure Substrate (나노구조기판의 형상 및 온도변화에 따른 액체 클러스터의 거동에 대한 분자동역학적 연구)

  • Ko, Sun-Mi;Jeong, Heung-Cheol;Shibahara, Masahiko;Choi, Gyung-Min;Kim, Duck-Jool
    • Journal of ILASS-Korea
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    • v.13 no.1
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    • pp.34-41
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    • 2008
  • Molecular dynamic simulations have been carried out to study the effect of the nano-structure substrate and its temperature on cluster laminating. The interaction between substrate molecules and liquid molecules was modeled in the molecular scale and simulated by the molecular dynamics method in order to understand behaviors of the liquid cluster on nano-structure substrate. In the present model, the Lennard-Jones potential is applied to mono-atomic molecules of argon as liquid and platinum as nano-structure substrate to perform simulations of molecular dynamics. The effect of wettability on a substrate was investigated for the various beta of Lennard-Jones potential. The behavior of the liquid cluster and nano-structure substrate depends on interface wettability and function of molecules force, such as attraction and repulsion, in the collision progress. Furthermore, nano-structure substrate temperature and beta of Lennard-Jones potential have effect on the accumulation ratio. These results of simulation will be the foundation of coating application technology for micro fabrication manufacturing.

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The Effect of Different Substrate Temperature on the Electrical Properties of Al-doped ZnO Thin Films (Al-doped ZnO 박막의 기판 온도에 따른 전기적, 광학적 특성)

  • Kim, Bong-Seok;Kim, Eung-Kwon;Lee, Kyu-Il;Oh, Su-Young;Song, Joon-Tae
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.10
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    • pp.1782-1785
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    • 2007
  • In this paper, the effect of substrate temperature on structural, electrical and optical properties of aluminium-doped zinc oxide (AZO) films were investigated. AZO thin films were prepared on glass substrate by pulsed DC magnetron sputtering technique. The properties of AZO were measured by using XRD, AFM, UV spectrophotometer, and hall effect measurement system. The resistivity of AZO films was improved under the condition of high substrate temperature. The resistivity decreased from $9.95{\times}10^{-2}\;{\Omega}-cm\;to\;1.1{\times}10^{-3}\;{\Omega}-cm$ as a result of high substrate temperature and the average transmittances in visible range were above 80%.

Enhancement of Magneto-optical Kerr Effect Signal from the Nanostructure by Employing Anti-reflection Coated Substrate

  • Kim, D.H.;You, Chun-Yeol
    • Journal of Magnetics
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    • v.13 no.2
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    • pp.70-75
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    • 2008
  • In this study, a MOKE (Magneto-optical Kerr effect) measurement method for magnetic nanostructures is proposed. Theoretically, the MOKE signal enhancement can be predicted and confirmed when an anti-reflection coated substrate is used. Since MOKE is a ratio of reflectivity and the difference between the reflectivities for two magnetic states, when the reflectivity of the substrate part is reduced by employing an anti-reflection coated substrate, MOKE signal enhancement can be achieved. The enhancement is confirmed by simple numerical MOKE calculations. When the reflectivity of an anti-reflection coated substrate is 0.7%, the calculated MOKE signal is about 79% of its bulk values for the 100-nm wide Fe nanowire with a 1500-nm radius laser beam. It was found that, for various numerical calculations, a larger MOKE signal is obtained relative to a smaller substrate reflectivity.

Effect of a Finite Square Substrate Plane on the Radiation Characteristics of a Microstrip Patch Antenna (유한한 정사각형 기판의 크기가 마이크로스트립 패치 안테나의 방사 특성에 미치는 영향)

  • Park, Jae-Woo;Kim, Tae-Young;Kim, Boo-Gyoun;Shin, Jong-Dug
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.46 no.2
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    • pp.114-125
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    • 2009
  • Effect of a finite square substrate plane on the radiation characteristics of a microstrip patch antenna is investigated. Effect of a finite square substrate plane on the resonance frequency and bandwidth is very small, while that on the radiation pattern is very large. The gain of front radiation and the direction of the maximum gain vary almost periodically with the length of a square substrate plane. The length of a square substrate plane for the maximum gam and the minimum gain of front radiation decrease as the electrical thickness of a substrate increases. The variation of the gain of front radiation with the length of a square substrate plane increases as the electrical thickness of a substrate increases. The variation of the radiation pattern with the length of a square substrate plane is almost determined by the electrical thickness of a substrate.

Thermal Effect Modeling for AIGaN/GaN HFET on Various Substrate (AlGaN/GaN HFET의 기판에 따른 열효과 분석 모델링)

  • Park, Seung-Wook;Shin, Moo-Whan
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11b
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    • pp.221-225
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    • 2001
  • In the paper, we report on the DC and Thermal effect of the GaN based HFET. A physics-based a model was applied and found to be useful for predicting the DC performance and Thermal effect of the GaN based HFET by Various substrate. The performance of device on the sapphire substrates is found to be significantly improve compared with that of a device with an sapphire substrate. The peak drain current of the device achieved at HFET on the SiC substrate

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Thermal Effect Modeling for AlGaN/GaN HFET on Various Substrate (AlGaN/GaN HFET의 기판에 따른 열효과 분석 모델링)

  • 박승욱;신무환
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.221-225
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    • 2001
  • In the paper, we report on the DC and Thermal effect of the GaN based HFET. A physics-based a model was applied and found to be useful for predicting the DC performance and Thermal effect of the GaN based HFET by Various substrate. The performance of device on the sapphire substrates is found to be significantly improve compared with that of a device with an sapphire substrate. The peak drain current of the device achieved at HFET on the SiC substrate

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A study on the effect of process parameters on the corrosion resistance of ion plated Tin films with Ti and Ni interlayers. (이온플레팅시 공정조건이 Ti 및 Ni 중간층을 갖는층을 갖는 TiN 박막의 내식성에 미치는 영향에 관한 연구)

  • 하희성;이종민;이인행;이정중
    • Journal of the Korean institute of surface engineering
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    • v.30 no.1
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    • pp.33-43
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    • 1997
  • The effects of process parameters substrate such as substrate current and substrate temperature on the corrosion resistance of ion plated TiN film were investigated. TiN fims were deposited on speed steel on which Ti or Ni hed been previously evaporated. Dense TiN films could be obtained under higher substrate current(1A) and substrate temperature($500^{\circ}C$), whereas TiN films deposited with lower substances current(0.5A) and substrate temperature($300^{\circ}C$) showed porous structure. The corrosion resistances of high speed steel was considerably increased when dense TiN films had been formed on it. The effect of Ti and Ni interlayer on the increase of the corrosion resistance was also significant with dense TiN films, while there was little effect of interlayer on the corrosion resistance when TiN films were porous. the effect of interlayer on the corrosion resistance was more outstanding with Ti then with Ni, because Ti reacts more easily with oxygen to form an oxide layer, and it also shows higher resistance against chlorine containing corrosion media.

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