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A Kaehler manifold with the axiom of anti-invariant 2-spheres is a complex space form. 相似文献
996.
None of the existing standards, which express the needs of engineers, consider correlation properties of traffic noise. But the correlation properties of traffic noise often seem to have a fundamental importance in certain engineering fields of noise control, such as the design of barriers for sound insulation and the detection of voices in noisy out-of-doors situations. In this paper, firstly, the correlation properties in the time domain and the frequency characteristics of the sound intensity at an observation point are discussed in the general case: i.e., for arbitrary values of quantities such as the propagation characteristics of the traffic sound energy, the numbers of lanes of road and of types of vehicles, the mixture ratios of vehicle types, the average number and respective acoustic power distributions of vehicles travelling with specific velocities on each lane of the road, the lengths of the straight sections of the road and the distance from the observation point. Next, the equivalence problem of replacing the several lanes of the road by a representative single lane is also discussed in detail, as an application of the statistical method. Finally, the values obtained from the theoretical expressions for several kinds of correlation functions of lower and higher orders are compared with experimental values, as obtained by use of the digital simulation technique. 相似文献
997.
Proton magnetic resonance in the α- and β-phases of Mg2NiHx was observed between 210 K and 480 K. The experimental results support that the motional narrowing due to a reorientation process occurs above 250 K in Mg2NiH4. 相似文献
998.
999.
Yuji Yamaguchi 《Journal of Physics and Chemistry of Solids》1980,41(4):327-330
Magnetization measurements have been made of single crystals of europium iron garnet (EuIG), Ga-doped EuIG and Al-doped EuIG. Cubic anisotropy constants K1 and K2 have been evaluated from the magnetization curves. Temperature dependence and concentration dependence of the anisotropy are compared with the theory by Foglio and van Vleck. 相似文献
1000.
Emission spectra of intrinsic and impurity-trapped excitons and their side- bands have been measured in CsMnF3 by a polarized time-resolved spectroscopy. From a biexcitonic decay of an emission an exciton- exciton interaction was found to be very small in contrast with those of MnF2 and KMnF3. Multimagnon sidebands have been assigned with the aid of calculation of magnon density of states. 相似文献