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1.
This is a review of two electrical equivalent circuits for multi-element magnetostatic wave transducers. The two circuit models are identified as a transmission line and a two terminal model. Both models have been extended to all three principal MSW modes of propagation to the point where computer programs have been written to plot phase and amplitude response as measured by commercial network analyzers. A review is provided of the basic assumptions, similarities and differences, advantages and disadvantages, and limitations of the two models. The useful range of them covers many cases of practical interest in the one to twelve Ghz frequency range.  相似文献   
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Several off-the-shelf animation software packages provide extensive capabilities, obviating the need for studios to develop their own software, except for highly specialized effects and interfaces. These capabilities make it feasible for a university to educate students in animation production without years of software development. The author discusses The UTS School of Cinema-Television and The USC Computer Animation Laboratory in particular  相似文献   
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The applicability of pseudoscalar functions, in general, and of the Osipov–Pickup–Dunmur chirality index, in particular, as consistent chirality measures is discussed. It is shown that due to the presence of chiral zeros these functions are unsuited to measure the chirality of objects described by more than two independent parameters.  相似文献   
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Summary Magnetic fields of the brain were recorded preceding selfinitiated finger, foot, toe movements, stimulus-triggered finger and toe movements, and speech. Slow magnetic-field shifts were found with morphology similar to coincident electrical potentials, but with very different distributions. Inferences from the data about localization of cerebral generators were discussed. These studies were supported by grants from the B.C. Research Council and N.S.E.R.C. of Canada.  相似文献   
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The coverages of adsorbed oxygen and CO on an Ir(111) surface have been determined using X-ray photoelectron spectroscopy (XPS) during the steady-state catalytic production of CO2. Correlating the coverages of the reacting adsorbates with the rate of CO2 production allows the kinetics of the CO oxidation reaction to be determined. The reaction is found to obey a Langmuir-Hinshelwood rate expression of the form RCO22 = k0[CO][O]exp(?EakT), where RCO2 is the rate of CO2 production, k0 is the pre-exponential factor of the reaction rate coefficient, [CO] and [O] are the surface coverages of CO and oxygen, respectively, and Ea is the activation energy for the oxidation reaction. The activation energy for this catalytic oxidation reaction is found to be approximately 9 kcalmole.  相似文献   
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Different failure modes of silicon are observed. Experimental results are not able to explain these variations clearly and therefore numerical simulations have been performed. In order to reduce high computational costs a simplified method to introduce weakened areas on silicon chips is presented. (© 2010 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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An analysis of modulated molecular beam mass spectrometry applied to linear systems, developed previously [H.-C. Chang and W.H. Weinberg, J. Chem. Phys. 66 (1977)], has been extended to include the important case of coupled mass transfer and chemical reaction. Three different cases have been considered explicitly, namely, (1) bulk diffusion and surface reaction, (2) bulk diffusion and bulk reaction, and (3) surface diffusion with reaction in a surface boundary zone. The possibility of the occurrence of stable chemical oscillations has been demonstrated for the case of bulk diffusion and surface reaction.  相似文献   
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