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951.
This paper presents procedures for constructing irreducible polynomials over GF(2s) with linearly independent roots (or normal polynomials or N-polynomials). For a suitably chosen initial N-polynomial F0(x)GF(2s) of degree n, polynomials Fk(x)GF(2s) of degrees n2k are constructed by iteratively applying the transformation x→x+x-1, and their roots are shown to form a normal basis of GF(2sn2k) over GF(2s). In addition, the sequences are shown to be trace compatible, i.e., the trace map TGF(2sn2k+1)/GF(2sn2k) fromGF(2sn2k+1) onto GF(2sn2k) maps the roots of Fk+1(x) onto those of Fk(x). 相似文献
952.
A new approach has been proposed to study the non-linear dynamics of local conformational distortions (kinks) activated in DNA polynucleotide chains that are inhomogeneous. The dependence of the dynamic characteristics of kinks on the chain composition has been obtained. The result has been applied to estimate the size, energy, density of energy, and velocity of kinks activated in chains having the binary sequence or the sequence similar to the sequences of promoters A1, A2, and A3 of the bacteriophage T7 genome. 相似文献
953.
Yuanyan Chen 《Computational Optimization and Applications》2008,41(3):337-348
This paper presents a recursive algorithm for constrained two-dimensional guillotine cutting problems of rectangular items.
The algorithm divides a stock plate into a sequence of small rectangular blocks. For the current block considered, it selects
an item, puts it at the left-bottom corner of the block, and determines the direction of the dividing cut that divides the
unoccupied region of the block into two smaller blocks for further consideration. The dividing cut is either along the upper
edge or along the right edge of the selected item. The upper bound obtained from the unconstrained solution is used to shorten
the searching space. The computational results on benchmark problems indicate that the algorithm can improve the solutions,
and is faster than other algorithms. 相似文献
954.
This paper proposes a self-adaptive optical flow method to detect moving objects in the video sequences. The method first estimates the original optical flow field with the optical flow algorithm, and then enhances the objects by a local mean algorithm, and finally filters out the noise with a self-adaptive threshold algorithm. The proposed method has a wide adaptivity to the size and the number of objects, and it also can effectively process the scenarios of complex background and that of the slight occlusion. Furthermore, it avoids the complicated and time-consuming preprocessing procedure. The results of the present method show that the moving objects can be detected effectively. 相似文献
955.
Szemerédi’s regularity lemma is a fundamental tool in graph theory: it has many applications to extremal graph theory, graph
property testing, combinatorial number theory, etc. The goal of this paper is to point out that Szemerédi’s lemma can be thought
of as a result in analysis. We show three different analytic interpretations.
Received: February 2006 Revision: April 2006 Accepted: April 2006 相似文献
956.
957.
Filomena Cianciaruso 《Journal of Mathematical Analysis and Applications》2006,322(1):329-335
Let be an operator, with X and Y Banach spaces, and f′ be Hölder continuous with exponent θ. The convergence of the sequence of Newton-Kantorovich approximations
958.
In the previous papers [J. Boos, T. Leiger, Dual pairs of sequence spaces, Int. J. Math. Math. Sci. 28 (2001) 9-23; J. Boos, T. Leiger, Dual pairs of sequence spaces. II, Proc. Estonian Acad. Sci. Phys. Math. 51 (2002) 3-17], the authors defined and investigated dual pairs (E,ES), where E is a sequence space, S is a BK-space on which a sum s is defined in the sense of Ruckle [W.H. Ruckle, Sequence Spaces, Pitman Advanced Publishing Program, Boston, 1981], and ES is the space of all factor sequences from E into S. In generalization of the SAK-property (weak sectional convergence) in the case of the dual pair (E,Eβ), the SK-property was introduced and studied. In this note we consider factor sequence spaces E|S|, where |S| is the linear span of , the closure of the unit ball of S in the FK-space ω of all scalar sequences. An FK-space E such that E|S| includes the f-dual Ef is said to have the SB-property. Our aim is to demonstrate, that in the duality (E,ES), the SB-property plays the same role as the AB-property in the case ES=Eβ. In particular, we show for FK-spaces, in which the subspace of all finitely non-zero sequences is dense, that the SB-property implies the SK-property. Moreover, in the context of the SB-property, a generalization of the well-known factorization theorem due to Garling [D.J.H. Garling, On topological sequence spaces, Proc. Cambridge Philos. Soc. 63 (1967) 997-1019] is given. 相似文献
959.
In this paper, we obtain a generalized Lucas polynomial sequence from the lattice paths for the Delannoy numbers by allowing weights on the steps (1,0),(0,1) and (1,1). These weighted lattice paths lead us to a combinatorial interpretation for such a Lucas polynomial sequence. The concept of Riordan arrays is extensively used throughout this paper. 相似文献
960.
R. F. Patterson 《Acta Mathematica Hungarica》2009,122(3):255-271
In this paper definitions for “bounded variation”, “subsequences”, “Pringsheim limit points”, and “stretchings” of a double sequence are presented. Using these definitions and the notion of regularity for four dimensional matrices, the following two questions will be answered. First, if there exists a four dimensional regular matrix A such that Ay = Σ k,l=1,1 ∞∞ a m,n,k,l y k,l is of bounded variation (BV) for every subsequence y of x, does it necessarily follow that x ∈ BV? Second, if there exists a four dimensional regular matrix A such that Ay ∈ BV for all stretchings y of x, does it necessarily follow that x ∈ BV? Also some natural implications and variations of the two Tauberian questions above will be presented. 相似文献