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Reports an error in On the relationship between lateralized brain function and orienting asymmetries by Christoph Teufel, Asif A. Ghazanfar and Julia Fischer (Behavioral Neuroscience, 2010[Aug], Vol 124[4], 437-445). In the article, we wrote that “the likelihood of obtaining at least one significant result at p n. The probability of obtaining at least one significant result is therefore 1 — (1— α)n. (The following abstract of the original article appeared in record 2010-16138-001.) Hemispheric specializations for language perception constitute one of the classic topic in cognitive neuroscience. Evidence has accumulated to suggest that lateralized acoustic processing is not restricted to humans but is also found in numerous animal species. One of the methods used to track such lateralization is the orienting-asymmetry paradigm, a simple, noninvasive means to study lateralization that has been applied to a range of different species ranging from harpy eagles to humans. Here we summarize and compare the results of studies employing the orienting-asymmetry paradigm, showing that these studies yield largely inconsistent results. We critically discuss the methodology's implicit assumptions and conclude that the empirical inconsistencies produced by the orienting-asymmetry paradigm, and the lack of sufficient evidence supporting the paradigm's underlying assumptions, warrant serious caution when interpreting results obtained by the method. Nontrivial interpretations of orienting-asymmetry results will require a much better understanding of how lateralized brain functions interact with overt behaviors. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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Flexible matrix composites (FMCs) consist of low modulus elastomers such as polyurethanes which are reinforced with high-stiffness continuous fibers such as carbon. This fiber–resin system is more compliant compared to typical rigid matrix composites and hence allows for higher design flexibility. Continuous, single-piece FMC driveshafts can be used for helicopter applications. In the present investigation, an optimization tool using a genetic algorithm approach is developed to determine the best combination of stacking sequence, number of plies and number of in-span bearings for a minimum-weight, spinning, misaligned FMC helicopter driveshaft. In order to gain more insight into designing driveshafts, various loading scenarios are analyzed and the effect of misalignment of the shaft is investigated. This is the first time that a self-heating analysis of a driveshaft with frequency- and temperature-dependent material properties is incorporated within a design optimization model. 相似文献
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Reinvestigation of the Lewis acid catalyzed rearrangement of some open-chain permethyloligosilanes with the Al(Fe)Cl(3) catalyst system exhibited several cases of additional reactivity: namely, a fragmentation/cyclization reaction. Introduction of (trimethylsilyl)methyl substituents into the oligosilane substrates strongly facilitated this reaction, yielding cyclic or bicyclic carbacyclosilanes. Investigations concerning the composition of the catalyst system indicated that the incorporation of about 0.1% FeCl(3) into the AlCl(3) lattice provided an effective catalyst. 相似文献
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Barry Haseltine Tor‐Ulf Weck Lars Meyer Rob van der Pluijm Oliver Dupont Christoph Alfes Wolfram Jaeger John Roberts Jonathan Silver Dirk Martens O. Pfeffermann Bastian Drewes Erhard Gunkler Jan Kubica Nebojsa Mojsilovic Erhard Gunkler Johann Marx Armin Ohler Hipolito Sousa Rui Sousa Romeu S. Vicente J. R. Mendes Silva Roberto Capozucca 《Mauerwerk》2011,15(6):348-361
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Microalloyed steels for forging applications have been newly developed in order to increase strength and toughness properties which thereby give the possibility for light weight constructions.The properties of these steels are set up by a controlled cooling directly from the forging heat without an additional heat treatment.This aim can be achieved on the one hand by a further development of precipitation hardening ferritic pearlitic steels (AFP-steel) due to an extended use of microalloying elements (AFP-M steel) and on the other hand by microalloyed steels which employ a bainitic microstructure (HDB steel).To adjust the targeted microstructure the temperature control has to be assured down to approx.500℃ for the AFP-M steels and down to approx.300℃ for the HDB steels. 相似文献
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Three-dimensional chemo-thermomechanically coupled simulation of curing adhesives including viscoplasticity and chemical shrinkage 总被引:1,自引:1,他引:0
Christoph Liebl Michael Johlitz Bülent Yagimli Alexander Lion 《Computational Mechanics》2012,49(5):603-615
Based on the one-dimensional material model developed by Liebl et al. (Arch Appl Mech, 2011) a three-dimensional viscoelastic-viscoplastic material model for small deformations of curing adhesives on the basis of continuum mechanics is proposed in this contribution. The model describes the most relevant phenomena which occur during curing processes in the automotive industry and includes the effects of temperature and degree of cure on the mechanical properties of the material. Thermal expansion as well as chemical shrinkage are also contained. The yield stress for the viscoplastic part of the model goes back to the work of Schlimmer and Mahnken (Int J Numer Meth Eng 63:1461–1477, 2005), but is formulated in reference to the degree of cure and the temperature. Therefore this model considers chemo-thermomechanical coupling and extends the plasticity approach of Schlimmer and Mahnken, which is devised for cured adhesives, to the whole curing range, from the uncured to the fully cured adhesive. A peculiar focus is hereby laid on epoxy resins used in the automotive industry as structural adhesives. 相似文献
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In-situ full-field measurements became one of the drivers for process understanding, model creation, validation and inverse analysis. Therefore, a novel spatio-temporal optical flow method for the robust measurement of higher-order strain derivatives is proposed. This computer vision approach overcomes inherent restrictions of established DIC methods. For advanced process analysis of shear cutting processes, the deformation curvature (2nd-order displacement derivative) and the respective rate (3rd-order displacement derivative) are of high interest. For the first time, it is possible to quantify experimentally these higher-order derivatives in sufficient quality with the proposed spatio-temporal optical flow approach. In addition, interesting correlations between the microstructure of the material and macroscopic process results are determined. This demonstrates the potential of the novel in-situ measurement approach for the advanced process analysis of metal forming processes in general. 相似文献