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991.
一种高并行度的H.264帧内预测器的VLSI设计 总被引:3,自引:2,他引:1
分析了帧内预测的17种模式,对于每个4×4大小块的16个像素点的不同模式的预测公式之间的相同运算,采用数字强度缩减的方法去除计算的冗余,提出了一种高并行度的帧内预测器,可以每个时钟周期处理16个像素点的预测值。基于SMIC0.18μm工艺,用verilog对该设计进行了VLSI实现,综合后的电路的关键路径最大时延为10ns,电路规模不超过1.4万门,数据吞吐率可以达到1600Msamples/s。从实现结果来看,与采用可重构方法的设计相比,该设计在相同的并行度下减小了电路面积,简化了控制逻辑。 相似文献
992.
No authorship indicated 《Canadian Metallurgical Quarterly》2006,61(8):811
Presents the citation for Anthony D. Wagner, who received the Award for Distinguished Scientific Early Career Contributions to Psychology (cognition and human learning) "for outstanding and innovative research on the neural basis of memory and executive control." A brief profile and a selected bibliography accompany the citation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
At the shipyards, the aluminium alloy 5083 is welded with a multi-pass sequence using the metal inert gas technique. If, while checking the weld integrity either after welding or during service, defects are detected in the vicinity of the weldment, repairs are usually employed to extend the service life.
The repair method involves removal of the upper passes, depending on the thickness and re-welding under the same conditions.
Purpose of this paper is to examine the microstructural changes accompanying repair welding, define their effect on properties of primary importance and set, if possible, an upper limit as far as the number of repairs is concerned. 相似文献
994.
Marcio Schwaab 《Chemical engineering science》2006,61(17):5791-5806
Model discrimination procedures are useful tools for selection of the best mathematical models to be used to represent a specific chemical process. The present paper presents and discusses a new sequential discrimination procedure, which makes use of model probabilities and concentrates the efforts on models with higher probabilities. Model probabilities are determined based on simple statistical arguments. Four numerical examples illustrate the application of the proposed discrimination procedure. The obtained results indicate that the new procedure is able to discriminate kinetic models with fewer experiments when compared to other procedures and also indicates when model discrimination is not possible and, thus, when the sequential design must be halted. Furthermore, the speed of the proposed discrimination procedure can be controlled by tuning a design parameter which reflects the analyst's mood (confidence) towards the discrimination problem and allows for increase or decrease of the number of experiments required for model discrimination during the sequential procedure. 相似文献
995.
G. Agostinelli A. Delabie P. Vitanov Z. Alexieva H.F.W. Dekkers S. De Wolf G. Beaucarne 《Solar Energy Materials & Solar Cells》2006,90(18-19):3438-3443
Surface recombination velocities as low as 10 cm/s have been obtained by treated atomic layer deposition (ALD) of Al2O3 layers on p-type CZ silicon wafers. Low surface recombination is achieved by means of field induced surface passivation due to a high density of negative charges stored at the interface. In comparison to a diffused back surface field, an external field source allows for higher band bending, that is, a better performance. While this process yields state of the art results, it is not suited for large-scale production. Preliminary results on an industrially viable, alternative process based on a pseudo-binary system containing Al2O3 are presented, too. With this process, surface recombination velocities of 500–1000 cm/s have been attained on mc-Si wafers. 相似文献
996.
精铸型壳"墨点"和铸件"黑皮"分析 总被引:1,自引:1,他引:0
陈冰 《特种铸造及有色合金》2006,26(12):805-807
以锆石砂粉为面层、高岭石系耐火材料为背层制成的精铸型壳浇注不锈钢铸件.经常在铸件表面出现大面积“黑皮”和相互孤立的凹陷疤痕,严重影响铸件质量.通过生产现场跟踪调查.结合俄歇能谱分析等手段.对缺陷部位化学组成和形成原因进行分析探讨.指出:铸件表面的疤痕与型壳表面“墨点”直接相关;而“黑皮”主要是硬壳面层中的氧化铁与铸件表面氧化产生的各种金属氧化物反应生成的尖晶石型复杂化合物。在此基础上,提出了防止此类缺陷的措施。 相似文献
997.
Wei Yan Matthew Charles Pritchard Chun-Hsien Chen Li Pheng Khoo 《The International Journal of Advanced Manufacturing Technology》2006,29(5-6):616-628
Collaboration with other members of the supply chain is one means by which small and medium sized enterprises (SMEs) can compete
in today’s global business environment. Thus, early stages of the new product development process involve both technical activities,
e.g., product platform definition, and commercial activities, e.g., bidding for contracts. This paper introduces an integrated
collaborative bidding and design system (CBDS) to help SMEs coordinate the two aspects. General sorting was employed for initial
requirements acquisition and platform definition; while a self-organizing map (SOM) neural network was combined with a concurrent
cost-schedule estimation strategy for refinement of design options and bid evaluation/preparation. A case study on cellular
phone design was then applied for illustrating the proposed prototype system. 相似文献
998.
介绍龙滩水电站尾水出口工程枯期围堰的设计参数及计算过程,结合施工过程中的实际情况,总结得出土石子围堰的闭气方法和浆砌石主围堰堰体防渗的应注意几个问题。 相似文献
999.
1. Introduction Side-wall acoustic logging tools, such as the Segmented Bond Tool (SBT) from Baker Atlas and the tools for open hole measurements, utilize acoustic transducers mounted on six pads to make compensated acoustic velocity and attenuation measurements which are not affected by mud weight, gas cut, fast formation effects, casing surface conditions or reasonable tool de- centralizing. Studies on the wave fields generated by these tools are very important to tool design and data int… 相似文献
1000.