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991.
Using the symbolic computation program MAPLE, we compute several terms of an asymptotic expansion for the distribution function of the logistic midrange. 相似文献
992.
993.
994.
Under a one-sided dissipative Lipschitz condition on its drift, a stochastic evolution equation with additive noise of the
reaction-diffusion type is shown to have a unique stochastic stationary solution which pathwise attracts all other solutions.
A similar situation holds for each Galerkin approximation and each implicit Euler scheme applied to these Galerkin approximations.
Moreover, the stationary solution of the Euler scheme converges pathwise to that of the Galerkin system as the stepsize tends
to zero and the stationary solutions of the Galerkin systems converge pathwise to that of the evolution equation as the dimension
increases. The analysis is carried out on random partial and ordinary differential equations obtained from their stochastic
counterparts by subtraction of appropriate Ornstein-Uhlenbeck stationary solutions. 相似文献
995.
In this paper, we establish two general theorems for equivalence between the Meir–Keeler type contractive conditions and the contractive definitions involving gauge functions. One of these theorems is an extension of a recent result of Lim (On characterization of Meir–Keeler contractive maps, Nonlinear Anal. 46 (2001) 113–120). 相似文献
996.
Given a1,a2,...,an ∈ ℤ^d$, we examine the set, G, of all non-negative integer combinations of these ai. In particular, we examine the generating function f(z) = ∑b ∈ Gzb. We prove that one can write this generating function as a rational function using the neighborhood complex (sometimes called
the complex of maximal lattice-free bodies or the Scarf complex) on a particular lattice in ℤn. In the generic case, this follows from algebraic results of Bayer and Sturmfels. Here we prove it geometrically in all
cases, and we examine a generalization involving the neighborhood complex on an arbitrary lattice. 相似文献
997.
We briefly comment on different perspectives on (1) the role of mathematics education theories, (2) the issue of plurality and healthy heterogeneity versus consolidation; (3) underlying inquiry systems or the implicit role of philosophy in theories of mathematics education. This paper also outlines developments within the European research scene on theory usage in mathematics education research, which complement the discussion at the 29th PME research forum in Melbourne. 相似文献
998.
The concept of strong interactions need not be limited to the sector of physics taken by QCD. While this domain is investigated by RHIC, LHC will be able to probe potential new strong interactions simultaneously: Finding the precise mechanism for electroweak symmetry breaking is one of the prime problems of physics. Intricately linked to this point is the question after the true nature or even the existence of the Higgs boson. Here, we present stronly interacting theories providing an explanation for the hierarchy problem and leading to a light composite Higgs boson, favoured by experimental data. Our variation of the standard model is consistent with precision data. We achieve this accordance by using technifermions in a higher representation of their gauge group. Anomaly conditions require at least one extra lepton family for some of the theories whereby they contain a natural dark matter candidate. We can accurately determine the masses of said leptons from experimental data. 相似文献
999.
E. N. Popova V. E. Yudin N. V. Kukarkina T. A. Kostereva I. V. Gofman V. V. Kudryavtsev 《Russian Journal of Applied Chemistry》2006,79(3):439-444
A series of foamed organoplastics based on a combination of foamed fully aromatic polyimide binders and Arimid T polyimide felt were prepared. New composite foamed organoplastics reinforced with montmorillonite nanoparticles were prepared using commercially available aromatic monomers. 相似文献
1000.
O. V. Bakbardina I. Yu. Pukhnyarskaya M. A. Gazalieva S. D. Fazylov E. M. Makarov 《Russian Journal of Applied Chemistry》2006,79(10):1726-1728
S-Amino derivatives of O-alkyldithiocarbonic acid were prepared by oxidative condensation of certain alkaloids with sodium xanthates. Some of the compounds synthesized exhibit fungicidal activity. 相似文献