• Title/Summary/Keyword: SaO2

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Simulated-Annealing Improvement Technique Using Compaction and Reverse Algorithm for Floorplanning with Sequence-Pair Model (Sequence-Pair 모델 기반의 블록 배치에서 압축과 배치 역변환을 이용한 Simulated-Annealing 개선 기법)

  • Seong, Young-Tae;Hur, Sung-Woo
    • Proceedings of the Korean Information Science Society Conference
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    • 2008.06b
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    • pp.598-603
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    • 2008
  • Sequence-Pair(SP)는 플로어플랜을 표현하는 모델 중 하나로써, 일반적으로 SP 모델을 사용하는 플로 어프래너 (floorplanner)는 Simulated-Annealing (SA) 알고리즙을 통해 해 탐색 과정을 수행한다. SP 모델을 이용한 다양한 논문에서 플로어플랜 성능 향상을 위해 평가함수의 개선과 스케줄링 기법 향상을 모색하였으며, 평가함수의 경우 O(nlogn) 시간 알고리즘이 존재한다. 본 논문에서는 SP 모델을 이용한 SA 기법에서 SA의 해 탐색 과정 중 초기 해 탐색 시점에서 좋은 해를 빠르게 찾을 수 있는 방법을 제안한다. 제안 기법은 기존의 SA 프레임펙을 수정한 2단계 SA 알고리즘으로써 SP에 대응하는 배치를 압축하고 압축한 배치를 역변환하는 과정으로 구성된다. 실험과 결과를 통해 제안기법의 효과를 보이며, 평균적으로 동일한 SA 환경 하에서 제안기법이 최종결과 면에서 우수함을 보인다.

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Fabrication and (Photo)Electrochemical Properties of Fe2O3/Na2Ti6O13/FTO Films for Water Splitting Process (물분해용 Fe2O3/Na2Ti6O13/FTO 박막 제조 및 특성평가)

  • Yun, Kang-Seop;Ku, Hye-Kyung;Kang, Woo-Seung;Kim, Sun-Jae
    • Corrosion Science and Technology
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    • v.11 no.2
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    • pp.65-69
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    • 2012
  • One dimensional(1D) $Na_2Ti_6O_{13}$ nanorods with 70 nm in diameter was synthesized by a molten salt method. Using the synthesized nanorods, about 750 nm thick $Na_2Ti_6O_{13}$ film was coated on Fluorine-doped tin oxide(FTO) glasss substrate by the Layer-by-layer self-assembly(LBL-SA) method in which a repetitive self-assembling of ions containing an opposite electric charge in an aqueous solution was utilized. Using the Kubelka-Munk function, the band gap energy of the 1D-$Na_2Ti_6O_{13}$ nanorods was nalyzed to be 3.5 eV. On the other hand, the band gap energy of the $Na_2Ti_6O_{13}$ film coated on FTO was found to be a reduced value of 2.9 eV, resulting from the nano-scale and high porosity of the film processed by LBL-SA method, which was favorable for the photo absorption capability. A significant improvement of photocurrent and onset voltage was observed with the $Na_2Ti_6O_{13}$ film incorporated into the conventional $Fe_2O_3$ photoelectrode: the photocurrent increased from 0.25 to 0.82 mA/$cm^2$, the onset voltage decreased from 0.95 to 0.78 V.

Effects of Salicylic Acid on Oxidative Stress and UV-B Tolerance in Cucumber Leaves (살리실산이 오이 잎의 산화적 스트레스와 UV-B 내성에 미치는 영향)

  • Hong, Jung-Hee;Kim, Tae-Yun
    • Journal of Environmental Science International
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    • v.16 no.12
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    • pp.1345-1353
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    • 2007
  • The effect of salicylic acid(SA) on antioxidant system and protective mechanisms against UV-B induced oxidative stress was investigated in cucumber(Cucumis sativus L.) leaves. UV-B radiation and SA were applied separately or in combination to first leaves of cucumber seedlings, and dry matter accumulation, lipid peroxidation and activities of antioxidant enzymes were measured in both dose and time-dependant manner. UV-B exposure showed reduced levels of fresh weight and dry matter production, whereas SA treatment significantly increased them. SA noticeably recovered the UV-B induced inhibition of biomass production. UV-B stress also affected lipid peroxidation and antioxidant enzyme defense system. Malondialdehyde(MDA), a product of lipid peroxidation, was greatly increased under UV-B stress, showing a significant enhancement of a secondary metabolites, which may have antioxidative properties in cucumber leaves exposed to UV-B radiation. Combined application of UV-B and SA caused a moderate increase in lipid peroxidation. These results suggest that SA may mediate protection against oxidative stress. UV-B exposure significantly increased SOD, APX, and GR activity compared with untreated control plants. Those plants treated with 1.0 mM SA showed a similar pattern of changes in activities of antioxidant enzymes. SA-mediated induction of antioxidant enzyme activity may involve a protective accumulation of $H_2O_2$ against UV-B stress. Moreover, their activities were stimulated with a greater increase by UV-B+SA treatment. The UV-B+SA plants always presented higher values than UV-B and SA plants, considering the adverse effects of UV-B on the antioxidant cell system. ABA and JA, second messengers in signaling in response to stresses, showed similar mode of action in UV-B stress, supporting that they may be important in acquired stress tolerance. Based on these results, it can be suggested that SA may participates in the induction of protective mechanisms involved in tolerance to UV-B induced oxidative stress.

Catalytic Cracking of Waste Lubricant Oil over Solid Acid Catalysts (고체산 촉매를 이용한 폐윤활유의 촉매 분해)

  • Hwang, In Hye;Yang, Hyeon Sun;Lee, Jong-Jib;Choi, Ko-Yeol;Lee, Chang-Yong
    • Applied Chemistry for Engineering
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    • v.23 no.3
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    • pp.320-325
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    • 2012
  • The catalytic cracking of waste lubricant oil was carried out on silica-alumina (SA), hydrogen-type mordenite (HM), and dealuminated mordenite (DM) with the silica/alumina ratio of 10.5, 10, and 12.5, respectively. Activity in the catalytic cracking was found to be in the order of SA > DM > HM. Carbon number distribution of the oil obtained over SA was similar to that of gasoline while that of the oil obtained over DM was similar to that of diesel. Carbon number distribution of the oil obtained over HM was similar to that between gasoline and diesel. Acid amounts of three kinds of catalysts were found to be in the order of $SA\;{\approx}\;HM$ > DM. Unlike HM and DM with pores of an uniform diameter below 10 A, SA had a pore size distribution within the range of 10 to 50 A. These results indicate that the acid amount and pore size of the catalysts may be related to the carbon number distribution of the cracked oil. The decrement of surface area by the accumulation of carbon and impurities on the surface of the catalyst was found to be in the order of SA > DM > HM.

Dynamic Stress Intensity Factor and Dynamic Crack Propagation Velocity in Nuclear Pressure Vessel Steels (원자로압력용기강의 동적 응력확대계수와 동적 균열전파속도)

  • Lee, O.S.;Han, M.K.;Han, M.S.
    • Journal of the Korean Society for Precision Engineering
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    • v.15 no.11
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    • pp.251-257
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    • 1998
  • 동적 파괴인성치 측정시스템과 동적 2차원 유한요소해석 프로그램을 개발하여 원자로압력용기에 사용하는 강(SA508 cl.3, SA516 gr.70)의 동적 파괴인성치와 동적 균열정지인성치를 평가하고 이에 대한 유용성을 확인하였으며, 이 시스템 을 이용하여 재료의 동적 파괴특성을 규명하였다. SA508 cl.3와 SA516 gr.70의 동적 균열전파속도(a)에 대응하는 동적 응력확대계수 (K(a))에 대한 실험식을 얻었으며, 동적 응력확대계수와 동적 균열전파속도와의 관계는 전형적인 "$\Gamma$" 형으로 나타남을 확인하였다.

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유기물처리된 박막의 XPS를 이용한 탄소함량에 대한 연구

  • O, De-Re-Sa;Kim, Hong-Bae
    • Proceedings of the Korean Society Of Semiconductor Equipment Technology
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    • 2006.10a
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    • pp.18-21
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    • 2006
  • 유기 반도체로서 트랜지스터에 사용되기 위해서 유기절연막은 $SiO_2$ 표면을 유기물로 처리하여 $SiO_2$ 박막 표면의 화학적 특성을 변화시키고 절연특성을 개선 함으로서 단위 소자의 특성을 개선시키고 있다. 그래서 $SiO_2$ 표면 위에 OTS를 처리하여 누설전류를 측정하였다. OTS처리함량에 따라서 누설전류가 흐르는 경향성은 다르게 나타났으며, 0.2% 처리된 박막에서 누설전류는 가장 적게 나타났다.

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Effects of Rhodobacter sp. SA16 on Lettuce(Lactuca sativa L.) in Plastic Film House (시설 상추에 대한 Rhodobacter sp. SA16 처리 효과)

  • Lee, Young-Han;Jeong, Han-Taek;Yun, Han-Dae
    • Korean Journal of Environmental Agriculture
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    • v.27 no.2
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    • pp.163-170
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    • 2008
  • This experiment was conducted to determine the development of mixed organic fertilizer using photosynthetic bacteria and mass production of mixed microbial compound for the environment-friendly agriculture. Photosynthetic bacteria, Rhodobacter sp. SA16 was isolated from soil collected by plastic film house. The SA16 strain was identified based on 16S rDNA sequence analysis and it is closely related to Rhodobacter sp.(100% similarity). The mixed organic fertilizer using SA16 was made of $N-P_2O_5-K_2O=60-10-20\;g\;kg^{-1}$ with combined soybean cake, sesame cake, powdered blood, fish meal, powdered bones and red-yellow soil. The mixed organic fertilizer 0.45, 0.90 and 1.35 Mg $ha^{-1}$ application in Ihyeon series was treated based on soil testing for lettuce cultivation in plastic film house. These results showed that the yield was increased the 18 and 19%over control by the mixed organic fertilizer application 0.45 and 0.90 Mg $ha^{-1}$, respectively. In the physical properties of the soil, the porosity of mixed organic fertilizer 1.35 Mg $ha^{-1}$ treatment was highest at 58.8%. Our results clearly revealed that the organic fertilizer using Rhodobacter sp. SA16 and mass production of mixed strains could be a useful technology in pursuing environment-friendly agriculture.