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801.
Under idealized conditions, electroconvection in a nematic liquid crystal sets in at a well-defined threshold of the driving ac voltage. Fluctuating convection rolls of a small amplitude below that threshold have been observed recently. The measurement of the amplitude of these fluctuations is described in detail in this paper. It is based on averaging the light intensity signals using the structure function and a quantitative analysis of the light deflection. 相似文献
802.
The stressed state of a thick three-layer plate with two circular holes is studied. Resolving functions are expressed in terms of Kolosov-Muskhelishvili integral potentials and modified Bessel functions. The problem is reduced to solving an infinite set of linear algebraic equations.Translated from Teoreticheskaya i Prikladnaya Mekhanika, No. 18, pp. 25–28, 1987. 相似文献
803.
804.
The determination of the past and the future of a physical system are complementary aims of measurements. An optimal determination of the past of a system can be achieved by an informationally complete set of physical quantities. Such a set is always strongly noncommutative. An optimal determination of the future of a physical system can be obtained by a Boolean complete set of quantities. The two aims can be reconciled to a reasonable degree with using unsharp measurements.This work was partly supported by the Bundesministerium für Forschung und Technologie, Bonn, the Research Institute for Theoretical Physics, Helsinki, and the University of Turku Foundation, Turku. 相似文献
805.
In the absence of gamma-ray observations from space in the eighties, interest has turned to ground-based observations in the TeV energy region. The best established sources are the Crab Nebula, Cygnus X-3 and Hercules X-1. 相似文献
806.
A. Hertz 《Graphs and Combinatorics》1989,5(1):149-157
We consider the graphs that can be obtained by deleting in a Meyniel graphG all the edges induced by an arbitrary set of nodes. These graphs will be called Slim and we prove that they are perfect. We study relations between Slim graphs and other well known classes of perfect graphs; particularly we show that the perfection of Slim graphs gives a proof to the conjecture of M. Preissmann that Meyniel graphs are locally perfect. 相似文献
807.
Large fault-tolerant interconnection networks 总被引:5,自引:0,他引:5
This paper deals with reliability and fault-tolerant properties of networks. We first survey general reliability properties of networks, in particular those concerning diameter vulnerability. Then we study in details reliability properties of some families of networks in particular de Bruijn and Kautz networks and their generalizations which appear as very good fault-tolerant networks. 相似文献
808.
W. Richard Strark 《Mathematical Logic Quarterly》1989,35(4):311-320
809.
810.
V. V. Tokarchuk 《Journal of Applied Mathematics and Mechanics》1989,53(6):708-715
The Langevin dynamics and fluctuational-dissipative relationships for the hydrodynamic fluctuations for systems which are described in the third Barnett order with respect to the gradients of the hydrodynamic variables are generalized on the basis of a kinetic approach. 相似文献