二元叠加码M_q~c(n,k,d)的性质

二元叠加码M_q~c(n,k,d)是二元叠加码M_q(n,k,d)的补阵,利用有限域F_2上向量的计算法则研究了二元叠加码M_q~c(n,k,d)的线性性质并证明了M_q~c(n,k,d)的析取(disjunct)性.     

二元叠加码M(i:d,k,n)的检纠错性质

对于自然数i,d,k,n,0i≤dkn,矩阵M(i:d,k,n)是一个基于有限集[n]={1,2,…,n}上两个不同子集相交关系的二元叠加码,研究了二元叠加码M(i:d,k,n)的汉明距离,给出了它的检错性和纠错性.     

二元叠加码M_q(n,k,d)码的平均汉明距离和均方差

根据二元叠加码(Binary Superimposed Code)M_q(n,k,d)的定义及有限域F_q上n维向量空间的k维子空间的维数性质定义了一个高斯组合函数,利用这个组合函数研究了M_q(n,k,d)码的平均汉明(Hamming)距离和它的均方差问题,给出了计算公式.     

二元码M_q(n,d,k)的检错性和纠错性

二元码Mq(n,d,k)是一个非适应性分组测试(NGT)算法的数学模型,是一个d-disjunct矩阵.二元码的汉明距离(Hamming)决定着码的检错性和纠错性,通过计算二元码Mq(n,d,k)的汉明距离,得到了它的检错性和纠错性.     

基于矩阵M_q(n,k,d)的可纠错非适应性群测

二元矩阵M_q(n,k,d)是一个非适应性分组测试(NGT)算法的数学模型,它是一个d-析取矩阵.在矩阵M_q(n,k,d)的基础上研究它的子矩阵M_q(n.k,d,z)的检纠错性质.     

二元叠加码M_q(n,k,d)的线性性质

二元叠加码M_q(n,k,d)是一个非适应性分组测试算法的数学模型,它是一个d-disjunct矩阵.利用有限域F_2上向量的计算法则研究了二元叠加码M_q(n,k,d)的线性性质,分别得到了M_q(n,k,d)存在线性性质和不存在线性性质的条件,为进一步研究M_q(n,k,d)提供了依据.     

一类二元容错码的扩展和算法

d-析取矩阵是非适应性群测(NGT)算法和二元叠加码最有效的数学模型,研究了d-析取矩阵M_q(n,k,d)的扩展码M_q~*(n,k,d)的析取性和容错性.     

二元叠加码M_q(n,k,d)的推广及其性质

利用有限域F_q上n维向量空间中子空间的相交关系定义了一个(0,1)-矩阵M_q(i:n,k,d),它是矩阵M_q(n,k,d)的推广.最后证明了这个矩阵M_q(i:n,k,d)是一个d-析取矩阵并且具有强容错能力.     

一个BSC码的扩展和它的性质

二元叠加码M_q(n,k,d)是一个非适应性分组测试(NGT)算法的数学模型,它是一个d-析取矩阵.将二元叠加码M_q(n,k,d)扩展到M_q(n,k,d,α)并研究了它的性质.     

基于二元叠加码M_q(n,k,d)的随机Pooling设计

以2002年Ngo Hung Q.和DU Ding-Zhu构作的二元叠加码M_q(n,k,d)为基础生成一个随机Pooling设计,研究了这个随机Pooling设计的参数和性质.     

一个二元叠加码M_q(t,k,d)生成的二元等重码

研究了二元叠加码Mq(t,k,d)也是一个二元等重码,给出了它成为最佳等重码的条件,研究了它的检错性.     

The Nonexistence of Ternary [38, 6, 23] Codes

It has been shown by Bogdanova and Boukliev [1] that there exist a ternary [38,5,24] code and a ternary [37,5,23] code. But it is unknown whether or not there exist a ternary [39,6,24] code and a ternary [38,6,23] code. The purpose of this paper is to prove that (1) there is no ternary [39,6,24] code and (2) there is no ternary [38,6,23] code using the nonexistence of ternary [39,6,24] codes. Since it is known (cf. Brouwer and Sloane [2] and Hamada and Watamori [14]) that (i) n₃(6,23) = 38> or 39 and d₃(38,6) = 22 or 23 and (ii) n₃(6,24) = 39 or 40 and d₃(39,6) = 23 or 24, this implies that n₃(6,23) = 39, d₃(38,6) = 22, n₃(6,24) = 40 and d₃(39,6) = 23, where n3<>(k,d) and d<>3(n,k) denote the smallest value of n and the largest value of d, respectively, for which there exists an [n,k,d] code over the Galois field GF(3).     

A New Table of Binary/Ternary Mixed Covering Codes

A table of upper bounds for K3,2(n1,n2;R), the minimum number of codewords in a covering code with n1 ternary coordinates, n2 binary coordinates, and covering radius R, in the range n = n1 + n2 13, R 3, is presented. Explicit constructions of codes are given to prove the new bounds and verify old bounds. These binary/ternary covering codes can be used as systems for the football pool game. The results include a new binary code with covering radius 1 proving K2(13,1) 736, and the following upper bound for the football pool problem for 9 matches: K3(9,1) 1356.     

n维单形的纳斯必特—彼得洛维奇不等式

利用优超理论将平面上关于三角形的纳斯必特彼得洛维奇不等式推广到 n维欧几里得空间中的 n维单形上 ,得到N 2n( N -1 ) d+nN ≤∑Nk=1sd+ak∑Ni=1,i≠ kak≤ N -nn +nn-1 ( d+1 ) ,式中 ai i=1 ,… ,N ;N =n( n+1 )2 为 n维单形 ∑A的棱长 ,d为任一非负实数 ,s=1n∑Ni=1ai     

利用有限向量空间的子空间构作二元(s,l)叠加码

一个二元叠加码(s,l)-码在许多领域有着极为广泛的应用.利用有限域F_q上的向量空间的子空间构作了矩阵M_q(m,d,k),并证明了它是一个(s,l)一码,计算了(s,l)-码的参数.     

The Nonexistence of Ternary [50,5,32] Codes

It is unknown (cf. Hill and Newton [8] or Hamada [3]) whether or not there exists a ternary [50,5,32] code meeting the Griesmer bound. The purpose of this paper is to prove the nonexistence of ternary [50,5,32] codes. Since there exists a ternary [51,5,32] code, this implies that n3(5,32) = 51, where n3(k,d) denotes the smallest value of n for which there exists a ternary [n,k,d] code.     

广义分数可扩图

研究一类广义分数可扩图即分数(n,k,d)-图的性质.图G是分数(n,k,d)-图即删去G的任意n个顶点后的剩余子图G′含有k-对集,且G′的任意k-对集都可扩充成G′的分数亏格-d对集.得到了分数(n,k,d)-图分别添加边和顶点的一系列递推关系.     

Shape Dimension and Intrinsic Metric from Samples of Manifolds

We introduce the adaptive neighborhood graph as a data structure for modeling a smooth manifold M embedded in some Euclidean space R^d. We assume that M is known to us only through a finite sample P \subset M, as is often the case in applications. The adaptive neighborhood graph is a geometric graph on P. Its complexity is at most \min{2^{^O(k)n, n²}, where n = |P| and k = dim M, as opposed to the n^{\lceil d/2 \rceil} complexity of the Delaunay triangulation, which is often used to model manifolds. We prove that we can correctly infer the connected components and the dimension of M from the adaptive neighborhood graph provided a certain standard sampling condition is fulfilled. The running time of the dimension detection algorithm is d2^{O(k^{7} log k)} for each connected component of M. If the dimension is considered constant, this is a constant-time operation, and the adaptive neighborhood graph is of linear size. Moreover, the exponential dependence of the constants is only on the intrinsic dimension k, not on the ambient dimension d. This is of particular interest if the co-dimension is high, i.e., if k is much smaller than d, as is the case in many applications. The adaptive neighborhood graph also allows us to approximate the geodesic distances between the points in P.     

奇数方幂和的通项公式

In this paper, by using superposition method, we aim to show that ∑^n i=1 （2/- 1）^2k-1 is the product of n2 and a rational polynomial in n2 with degree k- 1, and that ∑^ni=1 （2i - 1）^2k is the product of n（2n - 1）（2n ＋ 1） and a rational polynomial in （2n - 1）（2n ＋ 1） with degree k - 1. Moreover, recurrence formulas to compute the coefficients of the corresponding rational polynomials are also obtained.