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31.
Taking the m-power of an entry is a well-defined operation on the unimodular vectors in An modulo addition operations, if n is at least 3, for an arbitrary commutative ring A and any integer m. 相似文献
32.
We prove that the sequence of finite reflecting branching Brownian motion forests defined by Burdzy and Le Gall ([1]) converges in probability to the “super-Brownian motion with reflecting historical paths.” This solves an open problem posed in [1], where only tightness was proved for the sequence of approximations. Several results on path behavior were proved in [1] for all subsequential limits–they obviously hold for the unique limit found in the present paper.Mathematics Subject Classification (2000): Primary 60H15, Secondary 35R60Supported in part by NSF Grant DMS-0071486, Israel Science Foundation Grants 12/98 and 116/01 - 10.0, and the U.S.-Israel Binational Science Foundation (grant No. 2000065). 相似文献
33.
Following Rose, a subgroup H of a group G is called contranormal, if G = H G . In certain sense, contranormal subgroups are antipodes to subnormal subgroups. It is well known that a finite group is nilpotent if and only if it has no proper contranormal subgroups. However, for the infinite groups this criterion is not valid. There are examples of non-nilpotent infinite groups whose subgroups are subnormal; in paricular, these groups have no contranormal subgroups. Nevertheless, for some classes of infinite groups, the absence of contranormal subgroups implies the nilpotency of the group. The current article is devoted to the search of such classes. Some new criteria of nilpotency in certain classes of infinite groups have been established. 相似文献
34.
Arcadiy V. Krasheninnikov Konstantin E. Kon’kov Leonid A. Openov Vladimir F. Elesin 《Czechoslovak Journal of Physics》1996,46(3):1197-1198
The effect of ion irradiation on the superconducting transition temperatureT c and resistivityρ ab (T) of YBa2Cu3O7-x films with different oxygen content (initial temperatureT c0≈90 K and 60 K) is studied experimentally. The dependenciesT c /T c0 on residual resistivityρ o are obtained in very wide range 0.2<T c /T c0 <1 andρ o μΩ·cm. The critical values ofρ o , corresponding to the vanishing of superconductivity, are found to be an order of magnitude larger then those predicted by theory ford-wave pairing. At 0.5÷0.6<T c /T c0<1 the experimental data are in close agreement with theoretical dependencies, obtained for the anisotropics-wave superconductor within the BCS-framework. 相似文献
35.
Galtchouk Leonid I. Pergamenshchikov Serge M. 《Statistical Inference for Stochastic Processes》2022,25(1):127-158
Statistical Inference for Stochastic Processes - We consider drift estimation problems for high dimension ergodic diffusion processes in nonparametric setting based on observations at discrete... 相似文献
36.
37.
In this paper we present an inertia result for Stein equations with
an indefinite right hand side. This result is applied to establish connnections
between the inertia of invertible hermitian block Toeplitz matrices and associated
orthogonal polynomials. 相似文献
38.
Endre Boros Khaled Elbassioni Vladimir Gurvich Leonid Khachiyan 《Mathematical Programming》2003,98(1-3):355-368
A result of Balas and Yu (1989) states that the number of maximal independent sets of a graph G is at most p+1, where is the number of pairs of vertices in G at distance 2, and p is the cardinality of a maximum induced matching in G. In this paper, we give an analogue of this result for hypergraphs and, more generally, for subsets of vectors in the product of n lattices =1××n, where the notion of an induced matching in G is replaced by a certain binary tree each internal node of which is mapped into . We show that our bounds may be nearly sharp for arbitrarily large hypergraphs and lattices. As an application, we prove that the number of maximal infeasible vectors x=1××n for a system of polymatroid inequalities does not exceed max{Q,logt/c(2Q,)}, where is the number of minimal feasible vectors for the system, , , and c(,) is the unique positive root of the equation 2c(c/log–1)=1. This bound is nearly sharp for the Boolean case ={0,1}n, and it allows for the efficient generation of all minimal feasible sets to a given system of polymatroid inequalities with quasi-polynomially bounded right-hand sides .
This research was supported by the National Science Foundation (Grant IIS-0118635), and by the Office of Naval Research (Grant N00014-92-J-1375). The second and third authors are also grateful for the partial support by DIMACS, the National Science Foundation's Center for Discrete Mathematics and Theoretical Computer Science.Mathematics Subject Classification (2000):20E28, 20G40, 20C20 相似文献
39.
Boris Golinskii Leonid Golinskii 《Journal of Mathematical Analysis and Applications》1998,220(2):1050
The known conditions due to G. Baxter, Ya. L. Geronimus, and B. L. Golinskii which guarantee the uniform boundedness and/or uniform asymptotic representation for orthonormal polynomials on the unit circle are under consideration. We show that these conditions are in general not necessary. We discuss the relation between the orthonormal polynomials on the unit circle, the best approximations, and absolutely convergent Fourier series. 相似文献
40.
Leonid V. Kulik Andrey V. Pivtsov Alexander V. Bogachev 《Applied magnetic resonance》2010,37(1-4):353-361
The Na+-translocating nicotinamide adenine dinucleotide (NADH):quinine oxidoreductase (Na+–NQR) is a component of respiratory chain of various bacteria and it generates a redox-driven transmembrane electrochemical Na+ potential. It contains four different flavin prosthetic groups, including two flavin mononucleotide (FMN) residues covalently bound to the subunits NqrB and NqrC. Na+–NQR from Vibrio harveyi was poised at different redox potentials to prepare two samples, containing either both FMNNqrB and FMNNqrC or only FMNNqrB in a paramagnetic state. These two samples were comparatively studied using pulse electron paramagnetic resonance (EPR), electron-nuclear double resonance (ENDOR), and electron-electron double resonance (ELDOR) spectroscopy. The echo-detected EPR spectra and electron spin relaxation properties were very similar for flavin radicals in both samples. The splitting of the outer peaks in the proton ENDOR spectra, assigned to the C(8α) methyl protons, allows to identify both radicals as anionic flavosemiquinones. The mean interspin distance of 20.7 Å between these radicals was determined by pulse ELDOR experiment, which allows to estimate the edge-to-edge distance (r e) between these flavin centers as: 11.7 Å < r e < 20.7 Å. The direct electron transfer between FMNNqrB and FMNNqrC during the physiological turnover of the Na+–NQR complex is suggested. 相似文献