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32.
Cyclic codes are an important class of linear codes, whose weight distribution have been extensively studied. So far, most of previous results obtained were for cyclic codes with no more than three nonzeros. Recently, the authors of [37] constructed a class of cyclic codes with arbitrary number of nonzeros, and computed the weight distribution for several cases. In this paper, we determine the weight distribution for a new family of such codes. This is achieved by introducing certain new methods, such as the theory of Jacobi sums over finite fields and subtle treatment of some complicated combinatorial identities. 相似文献
33.
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35.
In this article, we focus on cyclic and negacyclic codes of length 2p^s over the ring R = Fp^m + uFp^m, where p is an odd prime. On the basis of the works of Dinh (in J.Algebra 324,940-950,2010), we use the Chinese Remainder Theorem to establish the algebraic structure of cyclic and negacyclic codes of length 2p^s over the ring Fp^m + uFp^m in terms of polynomial generators. Furthermore, we obtain the number of codewords in each of those cyclic and negacyclic codes. 相似文献
36.
利用已知弹性函数级联上高非线性度多输出布尔函数的方法构造(n,m,t)弹性函数,其非线性度为2^n-1-2^n-l/2-1+2^l/2.nlmax(n-l,m,t),在相同条件下改进了Kurosawa的非线性度2^n-1-2^n-l/2-1.特别地,本文构造了两类具体的向量弹性函数,得到两个不同的非线性度.本文所得函数的非线性度在大多数情况下是比较好的. 相似文献
37.
38.
J. Domscheit S. Trmnen B. Aengenvoort H. Hübel R. A. Bark M. Bergstrm A. Bracco R. Chapman D. M. Cullen C. Fahlander S. Frattini A. Grgen G. B. Hagemann A. Harsmann B. Herskind H. J. Jensen S. L. King S. Lenzi D. Napoli S. W.
degrd C. M. Petrache H. Ryde U. J. van Severen G. Sletten P. O. Tjm C. Ur 《Nuclear Physics A》1999,660(4):1211-392
High-spin states in 163Lu have been investigated using the Euroball spectrometer array. The previously known superdeformed band has been extended at low and high energies, and its connection to the normal-deformed states has been established. From its decay the mixing amplitude and interaction strength between superdeformed and normal states are derived. In addition, a new band with a similar dynamic moment of inertia has been found. The experimental results are compared to cranking calculations which suggest that the superdeformed bands in this mass region correspond to shapes with a pronounced triaxiality (γ≈±20°). 相似文献
39.
H. W. Schffer P. H. Mokler R. W. Dunford C. Kozhuharov A. Krmer A. E. Livingston T. Ludziejewski H. -T. Prinz P. Rymuza L. Sarkadi Z. Stachura Th. Sthlker P. Swiat A. Warczak 《Physics letters. A》1999,260(6):331-494
The photon energy differential shape of the second order matrix element for the two-photon (2E1) decay of the 1s2s1S0 level in He-like gold has been measured. The results are in agreement with a recent fully relativistic calculation. The corresponding 2E1 matrix element deviates from those in lighter He-like systems due to the strong central field in a heavy two-electron ion. 相似文献
40.
The minimum number of rows in covering arrays (equivalently, surjective codes) and radius-covering arrays (equivalently, surjective codes with a radius) has been determined precisely only in special cases. In this paper, explicit constructions for numerous best known covering arrays (upper bounds) are found by a combination of combinatorial and computational methods. For radius-covering arrays, explicit constructions from covering codes are developed. Lower bounds are improved upon using connections to orthogonal arrays, partition matrices, and covering codes, and in specific cases by computation. Consequently for some parameter sets the minimum size of a covering array is determined precisely. For some of these, a complete classification of all inequivalent covering arrays is determined, again using computational techniques. Existence tables for up to 10 columns, up to 8 symbols, and all possible strengths are presented to report the best current lower and upper bounds, and classifications of inequivalent arrays. 相似文献