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911.
In this paper, we characterize a class of graphs which can be embedded on a boolean cube. Some of the graphs in this class are identified with the well known graphs such asmulti-dimensional mesh of trees, tree of meshes, etc. We suggest (i) an embedding of anr-dimensional mesh of trees ofn
r
(r+1)–rn
r–1
nodes on a boolean cube of (2n)
r
nodes, and (ii) an embedding of a tree of meshes with 2n
2 logn+n
2 nodes on a boolean cube withn
2 exp2 (log (2 logn+1)]) nodes. 相似文献
912.
Arch D. Robison 《BIT Numerical Mathematics》1990,30(1):51-61
We discuss several improvements to an algorithm for computing the rewriting number of a group. Our improvements speed up the computation by a couple of orders of magnitude. With the faster algorithm, we have shown that the rewriting number of the symmetric groupS
5 is 8.Supported by a fellowship from the Shell Oil Company Foundation. 相似文献
913.
Saharon Shelah 《Algebra Universalis》2005,54(1):91-96
We show that if μ is a compact cardinal then the depth of ultraproducts of less than μ many Boolean algebras is at most μ
plus the ultraproduct of the depths of those Boolean algebras.
Received May 18, 2004; accepted in final form December 9, 2004. 相似文献
914.
We have measured the permeability of rhodamine-6G across Cx43 hemichannels reconstituted on a pipette tip. Cx43 hemichannels
were overexpressed in Sf9 cells, and affinity-purified. The hemichannels were reconstituted in a lipid bilayer on a pipette
tip by the tip-dip method. R6G in the pipette permeated across the channels into the bath. The permeability of R6G was quantified
by measuring R6G concentration in the bath after several hours by surface enhanced Raman spectroscopy (SERS) with 100 nm silver
colloid particles. The ratio of the permeability of dye to salt, as extracted by this combined electrical-SERS technique,
is compatible with similar ratios for other dyes across whole gap junction channels. The results for the permeability ratio
were further compared to fluorescence measurements. The novel combination of patch and SERS techniques can be extended to
quantifying the transport of biologically significant non-fluorescent molecules, such as cAMP and IP3, across 1 nm sized pores,
such as the gap junction channel. 相似文献
915.
Anis Rezgui 《Acta Appl Math》2005,89(1-3):271-286
In this work we study partial differential operators of infinite order on spaces of entire functions, generalizing some of
the results presented in [2] and [5] to the new spaces introduced in [3]. 相似文献
916.
Seán Dineen 《Mathematische Annalen》2006,334(2):395-412
Using tensor products and a generalised spectrum, we extend to infinite dimensional domains classical results on the ideals
generated by a finite or countable set of elements in a Fréchet algebra. 相似文献
917.
The Weierstrass semigroup H(P) is well known and has been studied. Recently there has been a renewed interest in these semigroups because of applications in coding theory. Generalizations of the Weierstrass semigroup H(P) to n-tuples P1,…,Pn have been made and studied. We will state and study another possible generalization. 相似文献
918.
We prove that the class of finite dimensional selfinjective algebras over a field which admit Galois coverings by the repetitive
algebras of the quasitilted algebras, with Galois groups generated by compositions of the Nakayama automorphisms with strictly
positive automorphisms, is invariant under stable and derived equivalences.
Dedicated to Claus Michael Ringel on the occasion of his sixtieth birthday 相似文献
919.
Armengol Gasull 《Journal of Differential Equations》2005,213(2):255-288
The generic isolated bifurcations for one-parameter families of smooth planar vector fields {Xμ} which give rise to periodic orbits are: the Andronov-Hopf bifurcation, the bifurcation from a semi-stable periodic orbit, the saddle-node loop bifurcation and the saddle loop bifurcation. In this paper we obtain the dominant term of the asymptotic behaviour of the period of the limit cycles appearing in each of these bifurcations in terms of μ when we are near the bifurcation. The method used to study the first two bifurcations is also used to solve the same problem in another two situations: a generalization of the Andronov-Hopf bifurcation to vector fields starting with a special monodromic jet; and the Hopf bifurcation at infinity for families of polynomial vector fields. 相似文献
920.
A nonparametric statistical model of small diffusion type is compared with its discretization by a stochastic Euler difference
scheme. It is shown that the discrete and continuous models are asymptotically equivalent in the sense of Le Cam's deficiency
distance for statistical experiments, when the discretization step decreases with the noise intensity ε.
Received: 12 April 1996 / Revised version: 29 October 1997 相似文献