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971.
改进形态学相关算法以识别高相似度灰度图像 总被引:3,自引:3,他引:0
从形态学角度定义了灰度联合图像相似度,提出两种基于位表示法形态学相关算法的改进算法,通过提取位表示法的图像片边缘特征或二元化位表示法的图像片功率谱,以提高位表示法形态学相关算法对高相似度灰度图像的识别能力。 相似文献
972.
L. I. Arkhipova M. G. Lebedev Yu. N. Sadkov 《Computational Mathematics and Modeling》1991,2(3):351-356
Translated from Aktual'nye Voprosy Prikladnoi Matematiki, pp. 228–235, 1989. 相似文献
973.
ρ-混合序列加权和的完全收敛性及其应用 总被引:1,自引:1,他引:0
本文研究了ρ-混合序列加权和的一些强极限定理,利用最大值矩不等式,获得了ρ-混合序列加权和的完全收敛性.并将此结果应用于线性回归模型参数的最小二乘估计及非参数回归模型的权函数估计. 相似文献
974.
XU Yichao CHEN Minru & MA Songya Academy of Mathematics Systems Science Chinese Academy of Sciences Beijing China College of Mathematics Information Sciences Henan University Kaifeng China 《中国科学A辑(英文版)》2006,49(10):1392-1404
We known that the maximal connected holomorphic automorphism group Aut (D)(0) is a semi-direct product of the triangle group T(D) and the maximal connected isotropic subgroup Iso(D)(0) of a fixed point in the complex homogeneous bounded domain D and any complex homogeneous bounded domain is holomorphic isomorphic to a normal Siegel domain D(VN,F). In this paper, we give the explicit formula of any holomorphic automorphism in T(D(VN, F)) and Iso(D(VN,F))(0), where G(0) is the unit connected component of the Lie group G. 相似文献
975.
Haitao Zhang Shuxin Ouyang Zhaosheng Li Lifei Liu Tao Yu Jinhua Ye Zhigang Zou 《Journal of Physics and Chemistry of Solids》2006,67(12):2501-2505
Bi2O3/SrTiO3 composite powders have been prepared and their photocatalytic activities were investigated by photooxidation of methanol. These powders were characterized by UV-Visible diffuse reflectance spectra, SEM and X-ray diffraction (XRD). The results revealed that all the Bi2O3/SrTiO3 composite powders exhibited higher photocatalytic activity than pure SrTiO3, Bi2O3 and TiO2 (P25) under visible light irradiation (λ>440 nm). The effects of the Bi2O3 contents on the photocatalytic activities of the composite powders were examined, the photocatalytic activities increased with the content of Bi2O3 increasing to a maximum of 83% and then decreased under visible light irradiation. The effects of the calcination temperatures on the photocatalytic activities of the composite powders were also investigated. 相似文献
976.
Yu. A. Zarubin 《Fluid Dynamics》1991,26(1):75-81
A displacement model constructed on the assumption of the exchange of components between the volumes of the pore space moving and not moving in the direction of displacement is considered. The theoretical solution is shown to be in good agreement with the actual results of the displacement of oil by water. Criterial equations for predicting the interphase exchange coefficient and the relation between the nonmoving and moving volumes of the pore space are constructed on the basis of a series of experiments in uncemented porous media.Translated from Izvestiya Akademii Nauk SSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 91–97. January–February, 1991. 相似文献
977.
S. N. Vorob'ev Yu. B. Nechaev S. L. Prosvirnin 《Radiophysics and Quantum Electronics》1992,35(8):440-451
The mutual coupling of the radiating elements in microstrip antennas is studied using a rigorous electrodynamic approach in which the field singularities at the radiator edges are taken into account with analytic accuracy. A spectral method is employed in combination with a method of semi-inversion by extraction of the Green-function singularity. The degree of interaction of the elements of microstrip structures at the fundamental and higher current harmonicsis determined, and the applicability of various approximations is assessed.Radio-Astronomy Institute, Academy of Sciences of Ukraine. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 35, No. 8, pp. 688–701, August, 1992. 相似文献
978.
Malkov Yu. P. Davidyan A. A. Filippov Yu. E. Rotinyan M. A. 《Russian Journal of Applied Chemistry》2002,75(6):946-949
A plasmochemical technique for neutralizing ozone-destroying chladones and fluorine- and chlorine-containing wastes is considered. Experimental results obtained on applying this technique to neutralization of some halogen-containing substances are presented, together with the information gained on using the technological scheme of the process in designing and constructing an industrial installation for neutralizing wastes of a plant manufacturing polytetrafluoroethylene. 相似文献
979.
R. L. Safiullin L. R. Enikeeva S. Yu. Serenko V. D. Komissarov G. A. Tolstikov 《Russian Chemical Bulletin》1991,40(2):280-284
Alkanesulfonic peracids RSO4H effectively oxidize olefins to the corresponding epoxides. The kinetics and mechanism of this reaction are studied. It was shown that both the monomer and dimer form of the peracid act as oxidizing agents. The dependence of the weight constant of the reaction of monomer RSO4H with substituted acyclic olefins on the structure of the latter is described by the Taft equation. A linear correlation is established between log k2 and the inductive constants of the substituents on the oxygen atom in the peracid.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 333–337, February, 1991. 相似文献
980.
V. A. Batanov V. S. Petriv A. O. Radkevich A. L. Telyatnikov A. Yu. Volkov 《International Journal of Infrared and Millimeter Waves》1991,12(7):703-715
High power IR pumping beams self focusing and defocusing in NH3 Raman laser is investigated by numerical methods on the basis of the solution of nonlinear quasioptical equations. The analysis of self focusing have been done for a wide range of parameters of radiation and of active medium. Spatial evolution of the beam configuration have been investigated for different regimes of nonlinear diffraction. Developed model enables to allow exactly for the spectroscopic features of active molecules and may be applied to the analysis of the properties of powerful optically pumped FIR lasers. 相似文献