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991.
第Ⅰ种强度不对称三态叠加多模叠加态光场N次方Y压缩—第一正交相位分量的压缩情况 总被引:2,自引:0,他引:2
根据量子力学中的线性叠加原理,构造了由三个强度不等的多模相干态光场|{Zj(A)}>q、|{Zj(B)}>q和|{Zj(C)}>q的线性叠加所组成的第Ⅰ种强度不对称三态叠加多模叠加态光场|ψl(ABC)>q.利用多模压缩态理论,研究了态|ψl(ABC)>q的第一正交方分量(即磁场分量)的广义非线性等幂次N次方Y压缩特性.结果发现:①在上述各多模相干态光场中各模的强度和各模的初始相位各不相等的情况下,态|ψl(ABC)>q的第一正交分量-磁场分量在一定的条件下,总可呈现出周期性变化的、任意等幂次的N次方Y压缩效应;②当上述各多模相干态光场的强度和各模的初始相位相等时,态|ψl(ABC)>q的磁场分量的N次方Y压缩现象消失,态|ψl(ABC)>q可恒处于等幂次N-Y最小测不准态. 相似文献
992.
993.
An efficient time-domain algorithm for plane non-linear flexural vibrations of multi-layered composite beams, which are driven into the inelastic range by severe transverse loadings, is presented. The influence of an axial static preload is considered in the sense of the quasi-linear second-order theory of structures. The inelastic parts of strain are treated as additional sources of selfstress in the linear elastic background-structure, driving the elastic response into the inelastic one. The efficiency of this exact formulation lies in the fact that linear solution techniques can be used in their most powerful form: Rubin's useful formulation for the quasi-static second-order transfer-matrix of linear elastic structures is applied in combination with modal analysis. Having in mind multi-metal beams, the classical lamination theory is assumed to be valid. Beams with overhang composed of ideal elastic-plastic and viscoplastic layers are studied as example structures. The fictitious sources of selfstress are calculated from the different material laws of the layers in a numerical time-stepping procedure, where a generalized midpoint-rule in combination with Crisfield's secant-Newton procedure is used. 相似文献
994.
In this paper we will introduce a new type of incidence matrices, namely “Fuzzy incidence matrices”. Also we introduce the fuzzy simplicial complexes in its fuzzy form. We will describe some types of foldings especially the folding of a physical character. 相似文献
995.
Stability theorems for projections and central symmetrization 总被引:3,自引:0,他引:3
H. Groemer 《Archiv der Mathematik》1991,56(4):394-399
996.
本文用超声相比较方法测定了高Tc超导体La1.85Sr0.15CuO4,La2CuO4和YBa2Cu3O7的纵波和横波声速,进而导出了它们的纵向模量、切变模量、杨氏模量、泊松比、德拜温度及定体比热。在La1.85Sr0.15CuO4样品上,还进行了压力实验,发现所有弹性模量都是随压强增加而增加。定体比热cV和泊松比σ在高压下则略有下降。德拜温度是随压强增加而增加的。 相似文献
997.
Brecht S.H. Gladd N.T. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1992,20(6):678-690
The structuring of plasma shells expanding into a magnetized plasma at velocities less than the Alfven speed is considered. The structuring phenomenon is studied with hybrid simulations. The hybrid simulations are conducted for two characteristic parameter sets: one set representative of magnetized ion experiments and one set representative of unmagnetized ion experiment. A complementary theoretical study of structuring instabilities using nonlocal, two fluid theory is discussed. Under the conditions representative of the laser-target experiments, the simulation observed structuring with azimuthal wavelengths similar to those observed in the experiment. Fluid theory, on the other hand, predicts that the most rapidly growing azimuthal modes are much shorter than observations, a result consistent with previous theoretical analyses 相似文献
998.
A. Dyulgerov N. Handjieva H. Saadi S. Popov I. Baranovska 《Journal of mass spectrometry : JMS》1992,27(7):795-798
The direct chemical ionization mass spectra with isobutane of 14 silylated iridoid glucosides of different structural types were studied. The dependence of the intensity of different peaks on the structure and stereochemistry of the investigated compounds is discussed. 相似文献
999.
This paper is concerned with a class of nonlinear delay partial difference equations with variable coefficients, which may
change sign. By making use of frequency measures, some new oscillatory criteria are established. This is the first time oscillation
of these partial difference equations is discussed by employing frequency measures.
相似文献
1000.