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61.
In this note it is shown that every bounded linear operator T Э B(Y,Z)defined on a closed subspace Y of a Banach space X admits a generalized extension T Э B(X, V). Some examples of the applications are given; especially, a characterization of H.I. spaces is obtained. 相似文献
62.
Lasing features of dye—doped pendant drops added with polymer particles:spectral blueshift and intensity enhancement 下载免费PDF全文
When micrometre-sized polymer particles were added into a dye-doped pendant drop that acted as a quasi-two-dimensional circular resonator,we found a blueshift of the peak wavelength of its lasing spectrum.The lasing output was also enhanced by the particles.The spectral blueshift was explained by a model of dye lasing in a circular cavity.The model includes losses of the scattering particles,medium absorption,and radiation leakage,An optimum particle density for maximum lasing output was deduced.The results are consistent with our experimental findings. 相似文献
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Zhang Zhennan Ge Xiurun Li Yonghe 《Acta Mechanica Solida Sinica》2006,19(3):196-202
Only two macroscopic parameters are needed to describe the mechanical properties of linear elastic solids, i.e. the Poisson's ratio and Young's modulus. Correspondingly, there should be two microscopic parameters to determine the mechanical properties of material if the macroscopic mechanical properties of linear elastic solids are derived from the microscopic level. Enlightened by this idea, a multiscale mechanical model for material, the virtual multi-dimensional internal bonds (VMIB) model, is proposed by incorporating a shear bond into the virtual internal bond (VIB) model. By this modification, the VMIB model associates the macro mechanical properties of material with the microscopic mechanical properties of discrete structure and the corresponding relationship between micro and macro parameters is derived. The tensor quality of the energy density function, which contains coordinate vector, is mathematically proved. Prom the point of view of VMIB, the macroscopic nonlinear behaviors of material could be attributed to the evolution of virtual bond distribution density induced by the imposed deformation. With this theoretical hypothesis, as an application example, a uniaxial compressive failure of brittle material is simulated. Good agreement between the experimental results and the simulated ones is found. 相似文献
67.
INCREMENTAL HARMONIC BALANCE METHOD FOR AIRFOIL FLUTTER WITH MULTIPLE STRONG NONLINEARITIES 总被引:3,自引:0,他引:3
The incremental harmonic balance method was extended to analyze the flutter of systems with multiple structural strong nonlinearities. The strongly nonlinear cubic plunging and pitching stiffness terms were considered in the flutter equations of two-dimensional airfoil. First, the equations were transferred into matrix form, then the vibration process was divided into the persistent incremental processes of vibration moments. And the expression of their solutions could be obtained by using a certain amplitude as control parameter in the harmonic balance process, and then the bifurcation, limit cycle flutter phenomena and the number of harmonic terms were analyzed. Finally, numerical results calculated by the Runge-Kutta method were given to verify the results obtained by the proposed procedure. It has been shown that the incremental harmonic method is effective and precise in the analysis of strongly nonlinear flutter with multiple structural nonlinearities. 相似文献
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吴顺 《南昌大学学报(理科版)》1994,18(3):237-241
本文对n维理想玻了体进行了讨论,推导出了n维理想玻色气体的态密度和基本公式,并分析了玻色-爱因斯坦凝聚,以及它与维度的关系。 相似文献
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我校建筑经济设置的计算课程,按照教学大刚要求,珠算技术达标水平由原来的普通六级提高到五普通级,这就为教学工作提出了新的要求,增加了教学难度,为此,经过教学实践摸索,进行了因材施教.分类指导.普遍提高的教学方法的尝试,收到了较好的效果。 相似文献
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TheHAUSDORFFDIMENSIONANDMEASUREOFTHEGENERALIZEDMORANFRACTALSANDFOURIERSERIES¥RENFUThO;LIANGJINRONGAbstract:Thispaperstudiesth... 相似文献