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991.
S. A. Kuliev 《Mechanics of Solids》2007,42(1):97-103
We consider a uniformly rotating isotropic plate whose cross-section is a two-connected domain bounded from the outside by a circle of radius R and from inside by an ellipse with semiaxes a and b. The rectilinear cuts coming to the ellipse are located symmetrically on the real axis OX. On the imaginary axis OY, two point masses m are located at the distances ±id from the center of the plate. Such a plate can be considered as a plate under the action of bulk forces (forces of inertia), X, Y, and under the action of two lumped tensile forces P = mdw 2 applied at the points ±id. 相似文献
992.
Coding techniques for improving the reliability of information storage on noisy magnetic recording channels are considered. It is assumed that the Lorentzian channel model applies and that the retrieved signal is perturbed with additive white Gaussian noise. The immunity against additive noise of state-of-the-art codes such as DC-free, runlength-limited, and trellis codes are assessed 相似文献
993.
Prony's method is usually used for the determination of poles from experimental data in the singularity expansion method (SEM) literature, It is the aim here to show that this is not the best method and that Jain's pencil-of-functions (POF) method can be generalized to provide a better method. An example of such a method is given. 相似文献
994.
Koo K.P. Bucholtz F. Dagenais D.M. Dandridge A. 《Photonics Technology Letters, IEEE》1989,1(12):464-466
A compact fiber-optic magnetometer constructed using a short piece of amorphous metal wire (5-cm long×100-μm diameter) as the magnetostrictive transducer is discussed. The inherently large ratio of length to cross-sectional area results in a low demagnetization along the axial direction. A magnetostrictive constant of 5×10-5 /Oe2, which is 10-50 times larger than the reported values for transducers made from Metglas ribbons, was measured. Minimum detectable magnetic fields on the order of 10-5 Oe/Hz1/2 at 1 Hz were achieved using a 5-cm-long sensing fiber 相似文献
995.
996.
X-ray, DSC and optical studies of a new class of substances with aromatic rings in the lateral branches are reported. The thermal behaviour of the substances is discussed. The X-ray measurements lead to a structural model of the SA phases consisting of layer structures with intercalating molecules. 相似文献
997.
The use of multigrid methods in complex fluid flow problems is still under development. In this paper a full multigrid procedure has been incorporated in a finite volume solution for predicting fully developed fluid flow in a streamwise periodic geometry. Steady computations in two-dimensional body fitted co-ordinates have shown considerable savings in computation time by this multigrid method. 相似文献
998.
The loss distributions in silica-based waveguides are successfully measured using a jaggedness-free optical reflectometer (OLCR). The OLCR reduces jagged fluctuations which appear in Rayleigh backscattering measurements undertaken with conventional OLCRs to within ±1 dB by averaging the wavelength-dependent Rayleigh backscatter signals. Constant loss distributions and a step-like loss increase in the waveguides were clearly observed 相似文献
999.
Lullo G. McKee A. McLean C.J. Bryce A.C. Button C. Marsh J.H. 《Electronics letters》1994,30(19):1623-1625
Electroabsorption optical modulators have been fabricated on GaInAs/GaInAsP multiquantum well structures whose bandgap had been increased by laser photoabsorption-induced disordering. Modulation depths of 20 dB have been obtained in material which has been bandgap blue shifted by as much as 120 nm, while samples shifted by 80 nm gave depths as high as 27 dB 相似文献
1000.
The authors present experimental results which indicate that a Dy 3+-doped Ga:La:S glass fibre amplifier may be operated efficiently at 1.3 μm with an optimum device length significantly shorter than a comparable Pr3+-doped glass fibre amplifier. Moreover, the efficiency exceeds that obtained from the Pr3+-doped ZBLAN devices currently available 相似文献