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701.
Dang Vu Giang Thomas I. Seidman 《Journal of Mathematical Analysis and Applications》2005,305(2):631-643
First, we systematize earlier results on the global stability of the model of population growth. Second, we investigate the effect of delay on the asymptotic behavior when the nonlinearity f is a unimodal function. Our results can be applied to several population models [Elements of Mathematical Ecology, 2001 [7]; Appl. Anal. 43 (1992) 109-124; Math. Comput. Modelling, in press; Funkt. Biol. Med. 256 (1982) 156-164; Math. Comput. Modelling 35 (2002) 719-731; Mat. Stos. 6 (1976) 25-40] because the function f does not need to be monotone or differentiable. Specifically, our results generalize earlier result of [Delay Differential Equations with Applications in Population Dynamics, 1993], since our function f may not be differentiable. 相似文献
702.
Given a spectrum X, we construct a spectral sequence of BP*BP-comodulesthat converges to BP*(LnX), where LnX is the Bousfield localizationof X with respect to the JohnsonWilson theory E(n)*.The E2-term of this spectral sequence consists of the derivedfunctors of an algebraic version of Ln. We show how to calculatethese derived functors, which are closely related to local cohomologyof BP*-modules with respect to the ideal In+1. 2000 MathematicsSubject Classification 55N22, 55P60, 16W30. 相似文献
703.
The constructions appearing in the formality theorem by Kontsevich [9] and Tamarkin [13] are first made locally. In these references, sufficient conditions are given to globalize the formality maps. Kontsevich formality maps satisfy these conditions. In this Letter, we show that Tamarkins maps can also be constructed so as to satify these conditions, thus can be globalized. 相似文献
704.
We introduce for a crossed module (T,G,) an invariant H
2
q
(T,G,) (q being a nonnegative integer) that generalizes the second Eilenberg–MacLane homology group with coefficients in Z
q
. We give for a q-perfect crossed module, the universal q-central extension via the non-abelian tensor product modulo q of two crossed modules, whose kernel is the mentioned invariant. 相似文献
705.
Marco A. Farinati 《Algebras and Representation Theory》2003,6(3):303-331
We study the derived invariance of the cohomology theories Hoch
*, H
* and HC
* associated with coalgebras over a field. We prove a theorem characterizing derived equivalences. As particular cases, it describes the two following situations: (1) f: CD a quasi-isomorphism of differential graded coalgebras, (2) the existence of a cotilting bicomodule
C
T
D
. In these two cases we construct a derived-Morita equivalence context, and consequently we obtain isomorphisms Hoch
*(C)Hoch
*(D) and H
*(C)H
*(D). Moreover, when we have a coassociative map inducing an isomorphism H
*(C)H
*(D) (for example, when there is a quasi-isomorphism f: CD), we prove that HC
*(C)HC
*(D). 相似文献
706.
We define a noncommutative analogue of invariant de Rham cohomology. More precisely, for a triple (A, H, M) consisting of a Hopf algebra H, an H-comodule algebra A, an H-module M, and a compatible grouplike element in H, we define the cyclic module of invariant chains on A with coefficients in M and call its cyclic homology the invariant cyclic homology of A with coefficients in M. We also develop a dual theory for coalgebras. Examples include cyclic cohomology of Hopf algebras defined by Connes–Moscovici and its dual theory. We establish various results and computations including one for the quantum group SL(q,2). 相似文献
707.
We derive an approximation of codimension-one integral cycles(and cycles modulo p) in a compact Riemannian manifold bymeans of piecewise regular cycles: we obtain both flat convergence andconvergence of the masses. The theorem is proved by using suitableprincipal bundles with a discrete group. As a byproduct, we give analternative proof of the main results, which does not use the regularitytheory for homology minimizers in a Riemannian manifold. This also givesa result of -convergence. 相似文献
708.
Allahtan Victor Gnedbaye 《K-Theory》1998,13(2):169-178
Leibniz homology is a noncommutative homology theory for Lie algebras. In this paper, we compute low-dimensional Leibniz homology of extended Lie algebras. 相似文献
709.
We compute the cyclic homology of the algebraR[t]/(P(t)) relative to an arbitrary integral domainR. As an application, we compute the cyclic homology of number rings.Supported by N.S.F. Grant No. DMS-8807203. 相似文献
710.
Eric M. Friedlander 《K-Theory》1994,8(3):271-285
We compute the algebraic cycle homology for codimension 1 cycles on a variety over a perfect field; our computation agrees with Nart's computation of Bloch's higher Chow groups for codimension 1 cycles. We interpret algebraic cycle homology in terms of sheaves for Voevodsky's h-topology and use this to adapt a recent result of Suslin-Voevodsky: we establish for a complex variety that algebraic cycle homology with Z/n coefficients is naturally isomorphic to singular homology with Z/n coefficients.Partially supported by the NSF and NSA Grant #MDA904-90-H-4006. 相似文献