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991.
We introduce a new oriented evolving graph model inspired by biological networks. A node is added at each time step and is connected to the rest of the graph by random oriented edges emerging from older nodes. This leads to a statistical asymmetry between incoming and outgoing edges. We show that the model exhibits a percolation transition and discuss its universality. Below the threshold, the distribution of component sizes decreases algebraically with a continuously varying exponent depending on the average connectivity. We prove that the transition is of infinite order by deriving the exact asymptotic formula for the size of the giant component close to the threshold. We also present a thorough analysis of aging properties. We compute local-in-time profiles for the components of finite size and for the giant component, showing in particular that the giant component is always dense among the oldest nodes but invades only an exponentially small fraction of the young nodes close to the threshold. 相似文献
992.
R. Schumann 《Letters in Mathematical Physics》1996,37(3):249-271
We consider analytic properties of a class of dynamical systems which are defined by the action of certain homomorphism groups on von Neumann algebras if restricted to subalgebras. In particular, the analyticity of nuclear maps in the nuclear norm is shown. Furthermore, the statistical independence will be derived from nuclearity conditions. These results give new insight in the statistical independence of commuting algebras.This paper is a result of a collaboration with H. J. Borchers. 相似文献
993.
994.
Ti-49 at.% Ni thin films prepared by magnetron sputtering were annealed at 733-793 K for several time periods. Using small angle X-ray scattering, we have investigated the growth behavior of the crystalline particles in the TiNi films. We have obtained the size distribution of the samples annealed at 753 and 793 K for several time periods. The activation energy of growth of the crystalline particle was obtained. 相似文献
995.
996.
E. Buturović 《Letters in Mathematical Physics》1992,25(2):103-109
Some Kazama-Suzuki models admit a realization in terms of free bosons defined on a lattice. A criterion for such a realization and its construction are presented. Some examples are worked out.URA 14-36 du CNRS, associée à l'Ecole Normale Supérieure de Lyon et au Laboratoire d'Annecy-le-Vieux de Physique des Particules. 相似文献
997.
本文给出一个图形液晶显示模块同MCS-8098单片机的接口和控制技术。介绍了汉字信息处理和图形曲线显示的软件设计方法。 相似文献
998.
R. J. Gaboriaud 《Journal of Electronic Materials》1983,12(5):837-844
An essentially chemical thinning method for cross-sectional electron microscopy samples is described. This method can give
cross-sectional samples in less than three hours without ion milling. This technique has been applied to a silicon wafer that
had been amorphized by ion implantation and then partially annealed. An amorphous silicon layer as thin as 200 A was observed. 相似文献
999.
D.A Dawson 《Stochastic Processes and their Applications》1975,3(2):137-151
A formula is obtained for the global flow of information in a discrete Markov system which is defined on a locally finite graph. It is shown that the information flow is related to a random walk on the lattice of finite subgraphs of the graph. 相似文献
1000.