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991.
Five experiments are reported that investigate the distribution of selective attention to verbal and nonverbal components of an utterance when conflicting information exists in these channels. A Stroop-type interference paradigm is adopted in which attributes from the verbal and nonverbal dimensions are placed into conflict. Static directional (deictic) gestures and corresponding spoken and written words show symmetrical interference (Experiments 1, 2, and 3), as do directional arrows and spoken words (Experiment 4). This symmetry is maintained when the task is switched from a manual keypress to a verbal naming response (Experiment 5), suggesting the mutual influence of the 2 dimensions is independent of spatial stimulus-response compatibility. It is concluded that the results are consistent with a model of interference in which information from pointing gestures and speech is integrated prior to the response selection stage of processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
The measured plastic deformation of Mg-PSZ under stress contains contributions from both transformation and microcracking. A method is described to separate the contributions from transformation and microcracking for samples deformed in uniaxial tension. Such a separation enables the ratio of the longitudinal to transverse strains arising from the transformation to be estimated. The results are compared to the predictions of the shear–dilatation model of Chen and Reyes-Morel. Serious discrepancies are found between the experimental results and the predictions of the model and the possible reason for this is discussed.  相似文献   
993.
994.
This article describes a new method for building a natural language understanding (NLU) system, in which the system's rules are learnt automatically from training data. The method has been applied to design of a speech understanding (SU) system. Designers of such systems rely increasingly on robust matchers to perform the task of extracting meaning from one or several word sequence hypotheses generated by a speech recognizer. We describe a new data structure, the semantic classification tree (SCT), that learns semantic rules from training data and can be a building block for robust matchers for NLU tasks. By reducing the need for handcoding and debugging a large number of rules, this approach facilitates rapid construction of an NLU system. In the case of an SU system, the rules learned by an SCT are highly resistant to errors by the speaker or by the speech recognizer because they depend on a small number of words in each utterance. Our work shows that semantic rules can be learned automatically from training data, yielding successful NLU for a realistic application  相似文献   
995.
In order to determine the limiting velocity resolution that can be achieved using ultrasound, and to provide a model which can be generalized for the analysis of disturbed flow, a theoretical and experimental evaluation of the statistics of the received signal from laminar flow following the transmission of a train of short pulses is presented. The authors derive the autocorrelation function and determine the length of the correlated signal for various flow rates, comparing experimental measurements to theoretical predictions. High resolution experimental RF M-mode images are used to verify the theoretical model. Using a fluid with a density, viscosity, volume concentration, particle size, and speed of sound which is similar to that of blood, the authors show that the signal remains correlated for a long interval under many conditions of clinical interest. Including a comparison with experimental data, the effect of the lateral transit time through the sample volume and the axial velocity spread within the sample volume on the correlation of the received signal is evaluated. When a significant range of velocity components is present within the sample volume, this range is the limiting factor in the length of the correlated signal interval. Therefore, the use of a wideband signal, which reduces the sample volume size, produces a returned signal that may be correlated for a larger number of pulses, or for a longer time  相似文献   
996.
A specimen fromt he fossil forest of Dunarobba (Central Italy) attributed toTaxodioxylon gypsaceum was chemically analyzed particularly for its terpene content. Main chemical constituents show variations related to ageing and carbonization process, while terpene content exhibits a drop of mono- and sesquiterpenes in favour of diterpenes and higher MW compounds. All components are exclusively hydrocarbons and represent alicyclic or partially aromatic structures. The identified families include abietane, phyllocladane, norabietane and norpimarane among diterpenes and traces of cadinane and selinane among sesquiterpenes.  相似文献   
997.
MKT1 is required for m aintenance of K2 above 30°C in strains with the L-A-HN variant of the L-A double-stranded RNA virus of Saccharomyces cerevisiae. We report that MKT1 encodes a 92 979 Da protein with serine-rich regions and the retroviral protease signature, DTG, but with no substantial homology to proteins presently in the databases. This sequence is available from GenBank under Accession Number U09129.  相似文献   
998.
This article examines the special features of the III-V semiconductors, such as gallium arsenide and chemically related compounds, which make them an attractive alternative to silicon-based technology in the field of microelectromechanical systems. As in conventional electronic systems, it is not expected that the III-V compounds will become exclusively used in all instances, but rather a substantial niche market-exploiting the special advantages of the compound semiconductors-is likely to be established  相似文献   
999.
The exact distributions associated with the current compendial test requirements are generated by resorting to the well known Computer Intensive Algorithm method to establish the exact percentage point (limit) for RSD, corresponding to each selected cut-off probability level (confidence level) for each of the four possible experimental outcomes based on the USP-NF test requirements. A table is constructed to present the two-dimensional power function. The similarities between these tabular values and the current compendial RSD limits for 10 and 30 dosage units are extremely remarkable.

Minor differences exist, however. It is suggested that both the theoretical as well as the numerical approaches should be carried out to arrive at a comprehensive solution.  相似文献   
1000.
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