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11.
It is essential in the simulation of power electronics applications to model magnetic components accurately. In addition to modeling the nonlinear hysteresis behavior, eddy currents and winding losses must be included to provide a realistic model. In practice the losses in magnetic components give rise to significant temperature increases which can lead to major changes in the component behavior. In this paper a model of magnetic components is presented which integrates a nonlinear model of hysteresis, electro-magnetic windings and thermal behavior in a single model for use in circuit simulation of power electronics systems. Measurements and simulations are presented which demonstrate the accuracy of the approach for the electrical, magnetic and thermal domains across a variety of operating conditions, including static thermal conditions and dynamic self heating 相似文献
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A theory is presented that explains how the visual system infers the lightness, opacity, and depth of surfaces from stereoscopic images. It is shown that the polarity and magnitude of image contrast play distinct roles in surface perception, which can be captured by 2 principles of perceptual inference. First, a contrast depth asymmetry principle articulates how the visual system computes the ordinal depth and lightness relationships from the polarity of local, binocularly matched image contrast. Second, a global transmittance anchoring principle expresses how variations in contrast magnitudes are used to infer the presence of transparent surfaces. It is argued that these principles provide a unified explanation of how the visual system computes the 3-D surface structure of opaque and transparent surfaces. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
13.
In this paper we suggest a new statistical method of correcting the results of hot-line experiments for the effects of background sources and we use the new method to reassess the adequacy of three probability distributions proposed in the literature for image spread from line sources. The data are from sources labelled with 125I in semi-thin resin sections 0·4-0·8 μm in thickness. The new method reveals that two of the models describe the empirical distributions more closely than earlier analysis had suggested, and it confirms an increasing relationship between half distance of image spread and the thickness of the source. However, it also confirms that considerable ‘inter hot-line’ experimental variation remains, even after background correction. This suggests that multiple experiments are needed to produce reliable estimates of half distance. 相似文献
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Arash Sarhangi Fard Navid M. Famili Patrick D. Anderson 《Computers & Chemical Engineering》2008,32(7):1471-1481
The main objective of the present work is to modify the traditional mapping method for the simulation of distributive mixing of multiphase flows in geometries involving moving parts such as, internal mixers or twin-screw extruders without a limitation on their geometrical periodicity. The periodicity condition, limits the results of traditional mapping method to tracking mapping mesh between specific discrete time intervals or distances for that geometry is repeated, hence, result is only for fixed orientation of rotors. Imaginary domain method is introduced to track mapping mesh from one state to the next free of geometrical periodicity limitations. In this work the method is introduced and its applicability and accuracy is discussed in details. A two-dimensional (2D) simulation of mixing of two Newtonian fluids with different viscosities in an intermeshing internal mixer is used as a test case study. In this example the key issues of ability to predict mixing state in details for all orientations of rotors is presented. To reduce diffusion errors of mapping method in the boundaries of the rotors, mapping mesh refinement technique that relies upon one single reference mesh is also presented. 相似文献
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Steven S. Ross 《网络电信》2008,(8):13-13
Perhaps the most powerful claim that advocates of fiber can make,on top of the massive bandwidthfiber makes possible today, is that fiber is future-proof. That is, the fiber that is laid today can be upgraded so that the same strands of glass can carry massively more bandwidth in the future. 相似文献
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The authors describe their scientific and clinical interests in developing the panel Trauma, Dissociation, and Conflict: The Space Where Neuroscience, Cognitive Science, and Psychoanalysis Overlap, given at the 22nd Annual Spring Meeting of the Division of Psychoanalysis of the American Psychological Association. They cite the influence of the panelists, Philip M. Bromberg, Wilma Bucci, and Joseph LeDoux, on their own work. Specializing in the treatment of chronic pain, Anderson has developed a relational intersubjective technique informed by this interdisciplinary approach. Gold's work has focused on the distinction between dissociative processes and repression in traumatic memory. The relevance of trauma, dissociation, and conflict, heightened since September 11, 2001, could not have been anticipated in the planning of the panel. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Anamaria Martins Christophe Ringeissen Anderson Santana 《Electronic Notes in Theoretical Computer Science》2003,86(2):77
The adaptation of software components developed for a specific application in order to generate reusable components often includes some kind of generalization. This generalization may be carried out, for instance, by the renaming of some identifiers or by its parameterization. In our work, we are specially interested in the generalization by parameterization of algebraic specification components. Generalization and some other transformations on algebraic specifications are being integrated in the FERUS tool. This tool was initially developed for the Common Algebraic Specification Language, called CASL, and we show in the paper its adaptation to the new version of the rule-based programming language ELAN. 相似文献