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21.
A method of detecting the magnetic field variation is proposed and implemented experimentally. The method employs the rotation
of the speckle pattern of light transmitted through an optical fiber that is placed into a longitudinal magnetic field and
the recording of a holographic grating in a photorefractive crystal using the speckle field. The possibility of detecting
the shape of a 0.15-s magnetic field pulse is demonstrated experimentally. 相似文献
22.
Lanin AA Voronin AA Sokolov VI Fedotov IV Fedotov AB Akhmanov AS Panchenko VY Zheltikov AM 《Optics letters》2011,36(10):1788-1790
Slow-light effects induced by stimulated Raman scattering in polymer waveguides on a printed circuit board are shown to enable a widely tunable delay of broadband optical signals, suggesting an advantageous platform for optical information processing and ultrafast optical waveform transformation. 相似文献
23.
Voronin AA Fedotov IV Doronina-Amitonova LV Ivashkina OI Zots MA Fedotov AB Anokhin KV Zheltikov AM 《Optics letters》2011,36(4):508-510
Light-assisted ionization accompanying coherent anti-Stokes Raman scattering (CARS) of ultrashort laser pulses in brain tissue is shown to manifest itself in a detectable blueshift of the anti-Stokes signal. This blueshift can serve as an indicator of ionization processes in CARS-based neuroimaging. 相似文献
24.
Evgenii?A.?PetrovEmail author Aleksei?A.?Dovgoshey 《Journal of Mathematical Sciences》2014,198(4):392-411
It was proved by R. Gomory and T. Hu in 1961 that, for every finite nonempty ultrametric space (X, d), the inequaliy \( \left| {\mathrm{Sp}(X)} \right|\leq \left| X \right|-1 \), where Sp(X) = {d(x, y) : x, y ∈ X, x ≠ y} , holds. We characterize the spaces X for which the equality is attained by the structural properties of some graphs and show that the set of isometric types of such X is dense in the Gromov–Hausdorff space of the isometric types of compact ultrametric spaces. 相似文献
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N. N. Kalmykov G. V. Kulikov Aleksei A. Silaev A. A. Silaev V. P. Sulakov 《Moscow University Physics Bulletin》2007,62(5):320-323
There is evidence for possible clustering in the arrival directions of extensive air showers (EASs). A program for analyzing EAS arrival directions has been developed to investigate this problem and the database of the Moscow State University EAS array for 1982–1989 has been analyzed. The distributions in equatorial coordinates have been derived for cosmic rays with energies E ≥ 2 × 1015 eV and zenith angles <40°. The uniformity of the derived distributions is verified using various statistical tests. 相似文献
30.
We consider strongly monotone continuous planar vector fields with a finite number of fixed points. The fixed points fall into three classes, attractors, repellers and saddles. Naturally, the relative positions of the fixed points must obey a set of restrictions imposed by monotonicity. The study of these restrictions is the main goal of the paper. With any given vector field, we associate a matrix describing the arrangement of the fixed points on the plane. We then use these matrices to formulate simple necessary and sufficient conditions which allow one to determine whether a finite set of attractors, repellers and saddles at given positions on the plane can be realized as the fixed point set of a strongly monotone vector field. 相似文献