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991.
Z. Kryžius 《Lithuanian Mathematical Journal》1985,25(3):243-250
992.
993.
Maximal semigroups dominated by a 0–1 matrix of a certain type are determined. The 0–1 matrices that dominate maximal bounded
and maximal commuting semigroups are given. Also semigroup modules over maximal semigroups dominated by a 0–1 matrix are discussed. 相似文献
994.
995.
Alžbeta Krutošiková 《Chemistry of Heterocyclic Compounds》1995,31(10):1219-1221
Department of Organic Chemistry, Slovak Technical University, 812 37 Bratislava, Slovak Republic. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1390–1392, October, 1995. Original article submitted August 24, 1995. 相似文献
996.
The purpose of this paper is to present the application of the Laser Doppler Vibrometer as a nonintrusive measurement instrument to detect shape and location of damage in fresco paintings. The paper discusses performance of the measurement instrument and outlines a measurement procedure capable of nonintrusive diagnostic of the state of conservation of works of art, based on frequency response analysis of wall surface vibration induced by acoustic excitation.The procedure for the measurement of wall surface vibration is described. A 2D map of surface vibration amplitude is produced by scanning the measurement point across the surface. This pseudo-image is then processed by image analysis techniques to determine the position and the shape of damaged areas. Experiments are performed on an artificial fresco with induced damage and on a real painting inside a church. 相似文献
997.
Miklavž Mastinšek 《Semigroup Forum》2002,66(1):140-150
Stability conditions for functional differential equations of the form: du(t)/dt = Au(t) + bAu(t ? h) + (a* Au)(t) are studied, where A is the infinitesimal generator of an analytic semigroup in a Hilbert space, b ≠ 0 and the convolution term contains a square integrable real function a ≠ 0. Norm discontinuity of the solution semigroup of the equation with discrete delay is avoided by studying the inverse of the characteristic operator. Sufficient and necessary conditions for the uniform exponential stability of the solution semigroup are obtained. The results are applied to a retarded partial integrodifferential equation. 相似文献
998.
The contradictions between the fluorescence and difference absorption data on primary processes of photosynthesis have been elucidated taking into account light absorption by the excited states as well as nonlinear processes taking place in the chromatophore samples excited selectively by picosecond light pulses. 相似文献
999.
H. G. Bohlen W. von Oertzen A. Blažević B. Gebauer S. M. Grimes R. Kalpakchieva T. N. Massey S. Thummerer 《Physics of Atomic Nuclei》2002,65(4):603-606
Excited states of 11Be have been studied with several transfer reactions. Nine states between 3.96 and 25.0 MeV excitation energy show the characteristic energy dependence of a rotational band. The deduced large moment of inertia is consistent with a 2α structure with large deformation. In 12Be four high-lying states observed at 7.3, 10.7, 14.6, and 21.7 MeV in the reaction 9Be(15N,12N)12Be, also form a rotational band with almost the same moment of inertia; tentative spin assignments of 2+–8+ are used. 相似文献
1000.