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961.
Abderrazak Bouaziz 《Journal of Functional Analysis》2009,257(10):3203-3217
We study the possibility of factoring a covariant distribution on reductive Lie algebras as finite sum of products of an invariant distribution by a covariant polynomial. 相似文献
962.
A self-transverse immersion of a smooth manifold M8k in has a double point self-intersection set which is the image of an immersion of a smooth four-dimensional manifold, cobordent to P4, P2×P2, P4+P2×P2 or a boundary. We will prove that for any value of k>1 the double point self-intersection set is a boundary. If k=1, then there exists an immersion of P2×P2×P2×P2 in with double point manifold boundary and odd number of triple points. In particular any immersion of oriented manifold in this dimension has double point manifold cobordant to a boundary. 相似文献
963.
In this paper we give conditions on an implication algebra A so that two congruences θ
1, θ
2 on A permute, i.e. θ
1 ∘ θ
2 = θ
2 ∘ θ
1. We also provide simpler conditions for permutability in finite implication algebras. Finally we present some applications
of these characterizations.
The support of Universidad Nacional del Sur and CONICET is gratefully acknowledged. 相似文献
964.
It is well-known that on a versal deformation of the Takens–Bogdanov bifurcation is possible to find dynamical systems that
undergo saddle-node, Hopf, and homoclinic bifurcations. In this document a nonlinear control system in the plane is considered,
whose nominal vector field has a double-zero eigenvalue, and then the idea is to find under which conditions there exists
a scalar control law such that be possible establish a priori, that the closed-loop system undergoes any of the three bifurcations: saddle-node, Hopf or homoclinic. We will say then that
such system undergoes the controllable Takens–Bogdanov bifurcation. Applications of this result to the averaged forced van der Pol oscillator, a population dynamics, and adaptive control systems
are discussed. 相似文献
965.
966.
K.R. Kazmi M.I. Bhat Naeem Ahmad 《Journal of Computational and Applied Mathematics》2009,233(2):361-371
In this paper, we give the notion of M-proximal mapping, an extension of P-proximal mapping given in [X.P. Ding, F.Q. Xia, A new class of completely generalized quasi-variational inclusions in Banach spaces, J. Comput. Appl. Math. 147 (2002) 369–383], for a nonconvex, proper, lower semicontinuous and subdifferentiable functional on Banach space and prove its existence and Lipschitz continuity. Further, we consider a system of generalized implicit variational inclusions in Banach spaces and show its equivalence with a system of implicit Wiener–Hopf equations using the concept of M-proximal mappings. Using this equivalence, we propose a new iterative algorithm for the system of generalized implicit variational inclusions. Furthermore, we prove the existence of solution of the system of generalized implicit variational inclusions and discuss the convergence and stability analysis of the iterative algorithm. 相似文献
967.
The concept of (f, σ)-pair (B, H)is introduced, where B and H are Hopf algebras. A braided tensor category which is a tensor subcategory of the category ^HM of left H-comodules through an (f, σ)-pair is constructed. In particularly, a Yang-Baxter equation is got. A Hopf algebra is constructed as well in the Yetter-Drinfel'd category H^HYD by twisting the multiplication of B. 相似文献
968.
969.
Shengle Fang Minghui Jiang 《Communications in Nonlinear Science & Numerical Simulation》2009,14(12):4292-4303
In this paper, we investigate the stability and Hopf bifurcation of a new regulated logistic growth with discrete and distributed delays. By choosing the discrete delay τ as a bifurcation parameter, we prove that the system is locally asymptotically stable in a range of the delay and Hopf bifurcation occurs as τ crosses a critical value. Furthermore, explicit algorithm for determining the direction of the Hopf bifurcation and the stability of the bifurcating periodic solutions is derived by normal form theorem and center manifold argument. Finally, an illustrative example is also given to support the theoretical results. 相似文献
970.
In this paper, we present some results on the bounded derived category of Artin algebras, and in particular on the indecomposable
objects in these categories, using homological properties. Given a complex X
*, we consider the set and we define the application . We give relationships between some homological properties of an algebra and the respective application l. On the other hand, using homological properties again, we determine two subcategories of the bounded derived category of
an algebra, which turn out to be the bounded derived categories of quasi-tilted algebras. As a consequence of these results
we obtain new characterizations of quasi-tilted and quasi-tilted gentle algebras.
Presented by Raymundo Bautista. 相似文献