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171.
Low-loss (<6 dB), flat-top, 16-wavelength, 100-GHz channel spacing DWDM (de)multiplexers are reported. The bulk-optics architecture used allows excellent thermal stability for operating temperature [-10, 60°C] 相似文献
172.
Tonchev V.D. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2002,48(4):975-977
It is proved that a class of q-ary (2n,n) formally self-dual codes obtained from symmetric matrices over GF (q), contains codes that meet the Varshamov-Gilbert bound. The codes are self-dual with respect to the symplectic inner product and yield quantum codes encoding one state with n q-ary qubits and having minimum distance proportional to n 相似文献
173.
Self-similarity in diffraction by a self-similar fractal screen 总被引:1,自引:0,他引:1
Lakhtakia A. Holter N. Varadan V. 《Antennas and Propagation, IEEE Transactions on》1987,35(2):236-239
Using the Sierpinski gasket as an example, it has been shown here that the paraxial Fraunhoffer-zone diffracted field of a self-similar fractal screen also exhibits self-similarity. This also establishes that fractal structures can be used with great profit in problems involving array syntheses. Recently, it has been shown that the Sierpinski gasket is itself a member of a much wider class of gaskets, and the potential for the use of fractal structures in electromagnetic (EM) problems may be vast indeed. 相似文献
174.
175.
176.
The mean convergence of various versions of a genetic algorithm are considered. A number of convergence statements are formulated
and relevant estimates are obtained. A hypothesis concerning the form of these estimates under variation of the structure
of a genetic algorithm is put forward.
Roman Riviyanovich Sharapov. Born 1981. Graduated from the Faculty of Mechanics and Mathematics, Ural State University, in 2003. Presently, a postgraduate
at the Department of Mathematical Economics at the same university. Scientific interests: genetic algorithms, neural networks,
and financial mathematics.
Aleksandr Vyacheslavovich Lapshin. Born 1980. Graduated from the Faculty of Mechanics and Mathematics, Ural State University, in 2003. Presently, a postgraduate
at the Department of Mathematical Economics at the same university. Scientific interests: financial mathematics, genetic algorithms,
and neural networks. 相似文献
177.
Androstenedione labeled with tritium at positions 1 and 2 was prepared. The molar radioactivity of the sample prepared using homogeneous catalysts was as high as 1.4-1.5 PBq mol-
1. [1,2-3H]Androst-4-ene-3,17-dione can be converted into the [1-3H]steroid with the molar radioactivity of 0.9 PBq mol-
1. 相似文献
178.
179.
Validity on the well-known Onsager reciprocal relations L 12=L 21 is verified in the kinetic theory of gases taking into account mass and heat transfer near the surface. Using an analytical solution to the ellipsoidal statistical equation (providing for the true Prandtl number), it is demonstrated that the Onsager relations are obeyed, at least to within exponential corrections of the type exp(−1/Kn) in the Knudsen number. 相似文献
180.