共查询到20条相似文献,搜索用时 0 毫秒
1.
Designs, Codes and Cryptography - Applications of permutation polynomials in cryptography are closely related to their cycle structures. For example, many block ciphers use permutation polynomials... 相似文献
2.
Mathematical Notes - We construct a family of flat isotropic nonhomogeneous tori in $$\mathbb{H}^n$$ and $$\mathbb{C}\mathrm{P}^{2n+1}$$ and find necessary and sufficient conditions for their... 相似文献
3.
Doklady Mathematics - An autonomous object moves at a constant speed along the shortest path, while bypassing an ordered collection of pairwise disjoint convex sets. The object is tracked by an... 相似文献
4.
Jan Bouwe van den Berg Federica Pasquotto Robert C. Vandervorst 《Mathematische Annalen》2009,343(2):247-284
Viterbo demonstrated that any (2n − 1)-dimensional compact hypersurface of contact type has at least one closed characteristic. This result proved the Weinstein conjecture for the standard symplectic
space (, ω). Various extensions of this theorem have been obtained since, all for compact hypersurfaces. In this paper we consider non-compact hypersurfaces coming from mechanical Hamiltonians, and prove an analogue of Viterbo’s result. The main result provides a strong connection
between the top half homology groups H
i
(M), i = n, . . . , 2n − 1, and the existence of closed characteristics in the non-compact case (including the compact case).
J. B. van den Berg is supported by NWO VENI grant 639.031.204. R. C. Vandervorst and F. Pasquotto are supported by NWO VIDI
grant 639.032.202. This research is also partially supported by the RTN project ‘Fronts-Singularities’. 相似文献
5.
We provide some new families of permutation polynomials of \({\mathbb {F}}_{q^{2n}}\) of the type \(x^rg(x^{s})\), where the integers r, s and the polynomial \(g \in {\mathbb {F}}_q[x]\) satisfy particular restrictions. Some generalizations of known permutation binomials and trinomials that involve a sort of symmetric polynomials are given. Other constructions are based on the study of algebraic curves associated to certain polynomials. In particular we generalize families of permutation polynomials constructed by Gupta–Sharma, Li–Helleseth, Li–Qu–Li–Fu. 相似文献
6.
On some classes of linear codes over $${\mathbb {Z}}_{2}{\mathbb {Z}}_{4}$$ and their covering radii
K. Chatouh K. Guenda T. Aaron Gulliver L. Noui 《Journal of Applied Mathematics and Computing》2017,53(1-2):201-222
In this paper, we define the simplex and MacDonald codes of types \(\alpha \) and \(\beta \) over \({\mathbb {Z}}_{2}{\mathbb {Z}}_{4}\). We also examine the covering radii of these codes. Further, we study the binary images of these codes and prove that the binary image of the simplex codes of type \(\alpha \) meets the Gilbert bound. 相似文献
7.
In this work, we focus on cyclic codes over the ring
\mathbbF2+u\mathbbF2+v\mathbbF2+uv\mathbbF2{{{\mathbb{F}}_2+u{\mathbb{F}}_2+v{\mathbb{F}}_2+uv{\mathbb{F}}_2}} , which is not a finite chain ring. We use ideas from group rings and works of AbuAlrub et.al. in (Des Codes Crypt 42:273–287,
2007) to characterize the ring
(\mathbbF2+u\mathbbF2+v\mathbbF2+uv\mathbbF2)/(xn-1){({{\mathbb{F}}_2+u{\mathbb{F}}_2+v{\mathbb{F}}_2+uv{\mathbb{F}}_2})/(x^n-1)} and cyclic codes of odd length. Some good binary codes are obtained as the images of cyclic codes over
\mathbbF2+u\mathbbF2+v\mathbbF2+uv\mathbbF2{{{\mathbb{F}}_2+u{\mathbb{F}}_2+v{\mathbb{F}}_2+uv{\mathbb{F}}_2}} under two Gray maps that are defined. We also characterize the binary images of cyclic codes over
\mathbbF2+u\mathbbF2+v\mathbbF2+uv\mathbbF2{{{\mathbb{F}}_2+u{\mathbb{F}}_2+v{\mathbb{F}}_2+uv{\mathbb{F}}_2}} in general. 相似文献
8.
Given an unbounded strongly pseudoconvex domain Ω and a continuous real valued function h defined on bΩ, we study the existence of a (maximal) plurisubharmonic function Φ on Ω such that Φ|b
Ω = h.
Supported by the MURST project “Geometric Properties of Real and Complex Manifolds”. 相似文献
9.
Any algebraic surface in which is fibered in cubics, so that the generic fibre is a twisted cubic, gives rise to a curve Γ in a suitable compactification
X of the space of smooth rational cubics of In this paper the case n = 4 is addressed and the corresponding space X is studied. We apply our results to complete the classification of smooth, rational surfaces in ruled in cubics.
This work is within the framework of the national research project “Geometry on Algebraic Varieties” Cofin 2006 of MIUR. 相似文献
10.
Aequationes mathematicae - In this paper, we consider the condition $$\sum _{i=0}^{n+1}\varphi _i(r_ix+q_iy)\in {\mathbb {Z}}$$ for real valued functions defined on a linear space V. We derive... 相似文献
11.
In an earlier paper the authors studied simplex codes of type α and β over
and obtained some known binary linear and nonlinear codes as Gray images of these codes. In this correspondence, we study weight distributions of simplex codes of type α and β over
The generalized Gray map is then used to construct binary codes. The linear codes meet the Griesmer bound and a few non-linear codes are obtained that meet the Plotkin/Johnson bound. We also give the weight hierarchies of the first order Reed-Muller codes over
The above codes are also shown to satisfy the chain condition.A part of this paper is contained in his Ph.D. Thesis from IIT Kanpur, India 相似文献
12.
Gianfranco Casnati 《Annali dell'Universita di Ferrara》2017,63(1):51-73
Let \(F\subseteq {\mathbb {P}^{3}}\) be a smooth determinantal quartic surface which is general in the Nöther–Lefschetz sense. In the present paper we give a complete classification of locally free sheaves \({\mathcal E}\) of rank 2 on F such that \(h^1(F,{\mathcal E}(th))=0\) for \(t\in \mathbb {Z}\). 相似文献
13.
14.
Given a hypersurface M of null scalar curvature in the unit sphere , n ≥ 4, such that its second fundamental form has rank greater than 2, we construct a singular scalar-flat hypersurface in as a normal graph over a truncated cone generated by M. Furthermore, this graph is 1-stable if the cone is strictly 1-stable. 相似文献
15.
Philippe Ellia 《Annali dell'Universita di Ferrara》2017,63(1):103-112
We give bounds on the rank of non uniform vector bundles on \(\mathbb {P}^n\) with a finite number of jumping lines. 相似文献
16.
Steffen Fröhlich Frank Müller 《Calculus of Variations and Partial Differential Equations》2009,35(4):497-515
We study orthonormal normal sections of two-dimensional immersions in , which are critical for a functional of total torsion and which we call Coulomb sections. In particular, we establish upper bounds for the torsion coefficients in the case of non-flat normal bundles. With these
notes we continue a foregoing paper on surfaces in 相似文献
17.
Todd Kemp 《Journal of Theoretical Probability》2017,30(2):397-451
This paper studies the empirical laws of eigenvalues and singular values for random matrices drawn from the heat kernel measures on the unitary groups \({\mathbb {U}}_N\) and the general linear groups \({\mathbb {GL}}_N\), for \(N\in {\mathbb {N}}\). It establishes the strongest known convergence results for the empirical eigenvalues in the \({\mathbb {U}}_N\) case, and the first known almost sure convergence results for the eigenvalues and singular values in the \({\mathbb {GL}}_N\) case. The limit noncommutative distribution associated with the heat kernel measure on \({\mathbb {GL}}_N\) is identified as the projection of a flow on an infinite-dimensional polynomial space. These results are then strengthened from variance estimates to \(L^p\) estimates for even integers p. 相似文献
18.
Irene I. Onnis 《Annali di Matematica Pura ed Applicata》2008,187(4):667-682
We classify the profile curves of all surfaces with constant mean curvature in the product space , which are invariant under the action of a 1-parameter subgroup of isometries.
The author was supported by INdAM (Italy) and Fapesp (Brazil). 相似文献
19.
In this paper we present a new characterization of Sobolev spaces on . Our characterizing condition is obtained via a quadratic multiscale expression which exploits the particular symmetry properties of Euclidean space. An interesting feature of our condition is that depends only on the metric of and the Lebesgue measure, so that one can define Sobolev spaces of any order of smoothness on any metric measure space. 相似文献
20.
Cristinel Mortici 《Optimization Letters》2010,4(3):457-464
The aim of this paper is to establish new bounds for ratios involving the volume of the unit ball in mathbbRn{mathbb{R}^{n}}. 相似文献