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191.
An all alkoxide based sol–gel route was investigated for preparation of epitaxial La0.5Sr0.5CoO3 (LSCO) films on 100 SrTiO3 (STO) substrates. Films with 20–30 to 80–100 nm thickness were prepared by spin-coating 0.2–0.6 M (metal) solutions on the STO substrates and heat treatment to 800 °C at 2 °C min− 1, 30 min, in air. The films were epitaxial with a cube-on-cube alignment and the LSCO cell was strained to match the STO substrate of 3.905 Å closely; a and b = 3.894 Å and 3.897 Å for the 20–30 and 80–100 nm films, respectively. The c-axis was compressed to 3.789 Å and 3.782 Å for the 20–30 and 80–100 nm films, respectively, which resulted in an almost unchanged cell volume as compared to polycrystalline film and nano-phase powders prepared in the same way. The SEM study showed mainly very smooth, featureless surfaces, but also some defects. A film prepared in the same way on an -Al2O3 substrate was dense and polycrystalline with crystallite sizes in the range 10–50 nm and gave cubic cell dimensions of ac = 3.825 Å. The conductivity of the ca 30–40 nm thick polycrystalline film was 1.7 mΩcm, while the epitaxial 80–100 nm film had a conductivity of around 1.9 mΩcm. 相似文献
192.
In this article, we have proposed fast lower-error and area-efficient antilogarithmic converters. By employing new approximation schemes with two-region shift-and-add operations, our proposed converters can perform high-speed conversions from logarithmic numbers to binary numbers. Synthesis results show that our proposed converters can achieve time savings of over 32.5% and can save 42.3% of the area used compared with previously proposed methods. In addition, the percent error ranges for various logarithmic number system (LNS)-based operations used by our proposed logarithmic processor are lower than those of previous methods. Our proposed converters can be applied to LNS-based processors to ease the tremendous computation overhead and boost the performance. 相似文献
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Two types of montmorillonite (MMT), natural sodium montmorillonite (Na-MMT) and organically modified montmorillonite (OMMT), in different amounts of 1, 2, 5, 10 and 25 phr (parts per hundred resin), were dispersed in rigid poly (vinyl chloride) by two different methods: solution blending and solution blending + melt compounding. The effects on morphology, thermal and mechanical properties of the PVC/MMT nanocomposites were studied by varying the amount of Na-MMT and OMMT in both methods. SEM and XRD analysis revealed that possible intercalated and exfoliated structures were obtained in all of the PVC/MMT nanocomposites. Thermogravimetric analysis revealed that PVC/Na-MMT nanocomposites have better thermal stability than PVC/OMMT nanocomposites and PVC. In general, PVC/MMT nanocomposites prepared by solution blending + melt compounding revealed improved thermal properties compared to PVC/MMT nanocomposites prepared by solution blending. Vicat tests revealed a significant decrease in Vicat softening temperature of PVC/MMT nanocomposites prepared by solution blending + melt compounding compared to unfilled PVC. 相似文献
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Jan De Cock Stijn Notebaert Kenneth Vermeirsch Peter Lambert Rik Van de Walle 《Multimedia Systems》2010,16(2):139-149
In this paper, we examine spatial resolution downscaling transcoding for H.264/AVC video coding. A number of advanced coding
tools limit the applicability of techniques, which were developed for previous video coding standards. We present a spatial
resolution reduction transcoding architecture for H.264/AVC, which extends open-loop transcoding with a low-complexity compensation
technique in the reduced-resolution domain. The proposed architecture tackles the problems in H.264/AVC and avoids visual
artifacts in the transcoded sequence, while keeping complexity significantly lower than more traditional cascaded decoder–encoder
architectures. The refinement step of the proposed architecture can be used to further improve rate-distortion performance,
at the cost of additional complexity. In this way, a dynamic-complexity transcoder is rendered possible. We present a thorough
investigation of the problems related to motion and residual data mapping, leading to a transcoding solution resulting in
fully compliant reduced-size H.264/AVC bitstreams. 相似文献
198.
在战争的演化模型的研究中,为了控制和引导社会舆论,民众战争态度演化是战争复杂系统研究的莺要内容之一.考虑持不同战争态度的社会个体之间的相互作用率与其态度距离的关系和从众心理,提出了度量持不同态度社会个体相遇的相互作用率.分析了态度演化的三种过程,确定了不同态度之间转变的转移概率密度,建立了战争态度演化的动力学方程模型.引入一个序参量度量持各种战争态度人数的动态变化,定义了战争态度构型演化的相.仿真结果表明,得到外界支持的态度,最终持有的人数在社会中占多数,外界作用对社会民众态度转变,对大多数人是有效的,但有极少数人仍会坚持原来的态度. 相似文献
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Jan Mulkens Bob Streefkerk Hans Jasper Jos de Klerk Fred de Jong Leon Levasier Martijn Leenders 《电子工业专用设备》2008,37(3):13-19
论述了第五世代双扫描平台浸液式扫描曝光机的性能和进展。表明了在高速扫描状态下有生产价值的套刻和聚焦性能的实现。浸液式设备更多的关键部分与缺陷有关,而且该机的改进是通过有生产价值的缺陷水平方面来体现的。为了保持这种缺陷水平的改进效果,需要在圆片应用中进行专门稳定的测量。特加是边缘空泡除去(EBR)设计和圆片斜面良流线性是很重要的。 相似文献