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991.
The authors report on a flexible system that provides visual feedback to VLSI designers with a novel display method. The basic problem is to display simultaneously two or more functions f 1, f2, . . ., each of which depends on the two spatial variables x and y. The method is based on results from visual perception experiments, which indicated that the human visual system can view simultaneously two or more images that are separated in depth, even if they are combined (superimposed) over a common spatial domain. Two display modes have been implemented: a gray-level mode and a contour mode in which only the edges separating adjacent regions are displayed in an effort to make things easier for the user. This depth-separation technique allows the viewer to register spatially the x,y distribution of multiple variables in an animation sequence. The technique can be applied to many other situations in which a single-plane episode involves several variables  相似文献   
992.
Reasoning about actions necessarily involves tracking the truth of assertions about the world over time. The SIPE planning system retains the efficiency of the STRIPS assumption for this while enhancing expressive power by allowing the specification of a causl theory. Separation of knowledge about causality from knowledge about actions relieves operators of much of their representational burden and allows them to be applicable in a wide range of contexts. The implementation of causal theories is described, together with examples and evaluations of the system's expressive power and efficiency.  相似文献   
993.
In-circuit testing is commonly thought to be inefficient for a high level of quality control, and unable to match the high yields of functional testing. A quantitative study of 34,296 boards that represented the testing of 6,671,038 components reveals that in-circuit testing can produce high yields -96.9% in this case. The author looks at this study  相似文献   
994.
995.
Everyday memory performance was examined longitudinally in 2 groups of Ss meeting the diagnostic criteria for age-associated memory impairment (AAMI). One group of 157 participants in a drug trial for reversing memory loss in AAMI was tested over multiple sessions. The other group of 75 persons did not participate in a drug trial and thus was tested only twice. Both groups were retested for longitudinal follow-up about 4 yrs after initial session. Follow-up test performance remained fairly stable relative to initial performance in both groups. The drug study group showed large practice effects during the course of the drug studies, but these effects subsided after the drug studies' end. Implications regarding memory decline in the normal elderly and neuropsychological measurement issues are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
996.
997.
Y-Ba-Cu-O films with different surface treatments have been studied by photoelectrochemical and XPS measurements. The influence of etching by bromine in ethanol of these films has been followed by means of the electrochemical oxidation of ferrocene in an aprotic electrolyte. From the dependence of dark and photocurrent on etching time it is concluded that Y-Ba-Cu-O thin films on LaAlO3 are covered by a 1, 1nm thick nonstoichiometric surface layer. The cathodic polarization of Y-Ba-Cu-O at -0,9 V vs. Ag/AgCl in acetonitrile/0,1 M lithium perchlorate leads to the formation of a lithium-containing, oxygen-enriched surface layer. The photoelectrochemical response of the reduced films is similar to that of cuprous oxide and passive layers on copper.  相似文献   
998.
999.
1000.
In previous work, we have shown that a set of characteristics, defined as (code frequency) pairs, can be derived from a protein family by the use of a signal-processing method. This method enables the location and extraction of sequence patterns by taking into account each (code frequency) pair individually. In the present paper, we propose to extend this method in order to detect and visualize patterns by taking into account several pairs simultaneously. Two 'multifrequency' methods are described. The first one is based on a rewriting of the sequences with new symbols which summarize the frequency information. The second method is based on a clustering of the patterns associated with each pair. Both methods lead to the definition of significant consensus sequences. Some results obtained with calcium-binding proteins and serine proteases are also discussed.  相似文献   
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