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71.
The paper deals with a physical model for the calculation of the strip temperature in a hot rolling mill. Beside the heat transfer from the strip to the environment in the different mill sections a sub‐model for the material properties of steel including phase transitions is introduced. For the application in a process automation system an online adaptation of the model to the current state of the mill is indispensable. The adaptation is explained in detail. 相似文献
72.
A sensor-driven control model and a minimum effort control algorithm in terms of time and energy expended during the execution of a movement strategy are described and validated for a multijointed cooperating robotic manipulator. Considering smooth, human-like (anthropomorphic) movements, using joint motion profiles achievable in real time as well as sensory information from all joints, and evaluating the total work expended by each manipulator joint during the execution of a movement strategy, a minimum effort motion trajectory is synthesized to precisely and efficiently position the robotic arm end-effector. This sensor-based approach significantly reduces the computational requirements for such cooperative motion. The minimum effort control algorithm generates several human-like arm movement strategies and selects the best strategy on the basis of expendable effort. The algorithm has an inherent basis to deal with obstacles in an efficient way. Detailed examples are described from the simulation studies. © 1994 John Wiley & Sons, Inc. 相似文献
73.
本文提出生种新的带限信号的外推方法,该方法能够很好地抑制噪声干扰,且计算复杂性较低,本文给出算法,证明了收敛性,最后给出了误差计算机实验结果。 相似文献
74.
Chemical mechanical polishing of polymer films 总被引:2,自引:0,他引:2
Strategies to reduce capacitance effects associated with shrinking integrated circuit (IC) design rules include incorporating
low resistivity metals and insulators with low dielectric values, or “low-κ” materials. Using such materials in current IC
fabrication schemes necessitates the development of reliable chemical mechanical polishing (CMP) processes and process consumables
tailored for them. Here we present results of CMP experiments performed on FLARE™ 2.0 using a specialized zirconium oxide
(ZrO2) polishing slurry. FLARE™ 2.0 is a poly(arylene) ether from AlliedSignal, Inc. with a nominal dielectric constant of 2.8.
In addition, we provide insight into possible removal mechanisms during the CMP of organic polymers by examining the performance
of numerous abrasive slurries. Although specific to a limited number of polymers, the authors suggest that the information
presented in this paper is relevant to the CMP performance of many polymer dielectric materials. 相似文献
75.
76.
Laura M. Haas Michael J. Carey Miron Livny Amit Shukla 《The VLDB Journal The International Journal on Very Large Data Bases》1997,6(3):241-256
In this paper, we re-examine the results of prior work on methods for computing ad hoc joins. We develop a detailed cost model for predicting join algorithm performance, and we use the model to develop cost formulas
for the major ad hoc join methods found in the relational database literature. We show that various pieces of “common wisdom” about join algorithm
performance fail to hold up when analyzed carefully, and we use our detailed cost model to derive op
timal buffer allocation schemes for each of the join methods examined here. We show that optimizing their buffer allocations
can lead to large performance improvements, e.g., as much as a 400% improvement in some cases. We also validate our cost model's
predictions by measuring an actual implementation of each join algorithm considered. The results of this work should be directly
useful to implementors of relational query optimizers and query processing systems.
Edited by M. Adiba. Received May 1993 / Accepted April 1996 相似文献
77.
军事和空间技术的要求促进了微光技术的发展。微光图像实时处理技术是夜技术今后发展的重要方向,本文针对微光图像与脉冲激光测距仪的数据信息实时融合与显示的方法及其实现进行了研究。给出了系统框图及工作原理,为实现探测识别、跟踪的实时性、智能化和微型化,从而为研制新一代战术侦察与火控系统提供了具体有效的技术基础。 相似文献
78.
Schmidt Frank L.; Law Kenneth; Hunter John E.; Rothstein Hannah R.; Pearlman Kenneth; McDaniel Michael 《Canadian Metallurgical Quarterly》1993,78(1):3
Using a large database, this study examined 3 refinements of validity generalization procedures: (1) a more accurate procedure for correcting the residual standard deviation (SD) for range restriction to estimate SDp, (2) use of r? instead of study-observed rs in the formula for sampling error variance, and (3) removal of non-Pearson rs. The 1st procedure does not affect the amount of variance accounted for by artifacts. The addition of the 2nd and 3rd procedures increased the mean percentage of validity variance accounted for by artifacts from 70 to 82%, a 17% increase. The cumulative addition of all 3 procedures decreased the mean SDp estimate from .150 to .106, a 29% decrease. Six additional variance-producing artifacts were identified that could not be corrected for. In light of these it was concluded that the obtained estimates of mean SDp and mean validity variance accounted for were consistent with the hypothesis that the true mean SDp value is close to zero. These findings provide further evidence against the situational specificity hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
79.
钱张师 《纺织高校基础科学学报》1995,(4)
通过203名大学男生的课余健美训练,测量训练前后体质各项指标,统计分析后发现,健美训练可使肺活量、体重、胸围以及引体向上的次数等明显增加. 相似文献
80.
聚四氢呋喃及其下游产品的开发应用 总被引:2,自引:0,他引:2
本文论述了聚四氢呋喃技术进展、氨纶弹性纤维发展现状和国内外聚四氢呋喃产能和需求。 相似文献