Three-level secret sharing schemes from the twisted cubic

Three-level secret sharing schemes arising from the vector space construction over a finite field F are presented. Compared to the previously known schemes, they allow a larger number of participants with respect to the size of F. The key tool is the twisted cubic of PG(3,F).     

A stochastic model for a general load‐sharing system under overload condition

A load‐sharing parallel system functions if at least one unit in the system is functioning and the surviving units share the load. In most of research on load‐sharing system, the performance of the system has been studied only for the case when the lifetimes of components in the system follow exponential distributions. In this paper a load‐sharing parallel system is considered when the lifetimes of the units in the system are any continuous random variables. The reliability function of the system is derived and the problem of load allocation is also considered. Copyright © 2009 John Wiley & Sons, Ltd.     

Constructions for Anonymous Secret Sharing Schemes Using Combinatorial Designs

In an anonymous secret sharing scheme the secret can be reconstructed without knowledge ofwhich participants hold which shares.In this paper some constructions of anonymous secret sharing schemeswith 2 thresholds by using combinatorial designs are given.Let v(t,w,q)denote the minimum size of the setof shares of a perfect anonymous(t,w)threshold secret sharing scheme with q secrets.In this paper we provethat v(t,w,q)=(q)if t and w are fixed and that the lower bound of the size of the set of shares in[4]is notoptimal under certain condition.     

双联行星轮角度偏差对系统均载特性的影响

为了研究双联行星齿轮在实际设计参数下,其相对角度偏差对复合行星传动系统动力学特性的影响,采用集中参数法建立了3K-I型行星齿轮动力学模型,模型中将双联行星齿轮的相对角度偏差转化为啮合副齿侧间隙的变化,考虑了双联齿轮角度偏差、轮齿侧隙和时变啮合刚度等非线性因素,采用龙格库塔法求解了系统的时域响应并计算其均载系数。分析了不同工况、偏差下系统的动态特性。结果表明,存在双联行星轮角度偏差时,轻载下更容易发生齿轮的脱齿与冲击,系统的均载系数随着双联行星轮角度偏差差值及系统的负载降低而增大,各组行星轮角度偏差分布越集中,角度偏差对系统均载特性的影响越小;角度偏差分布同号时,对系统中某一对齿轮的承载影响明显;角度偏差分布异号时,对系统均载特性的影响最大。     

Detection of Cheaters in Vector Space Secret Sharing Schemes

A perfect secret sharing scheme is a method of distributing shares of a secret among a set P of participants in such a way that only qualified subsets of P can reconstruct the secret from their shares and non-qualified subsets have absolutely no information on the value of the secret. In a secret sharing scheme, some participants could lie about the value of their shares in order to obtain some illicit benefit. Therefore, the security against cheating is an important issue in the implementation of secret sharing schemes. Two new secret sharing schemes in which cheaters are detected with high probability are presented in this paper. The first one has information rate equal to 1/2 and can be implemented not only in threshold structures, but in a more general family of access structures. We prove that the information rate of this scheme is almost optimal among all schemes with the same security requirements. The second scheme we propose is a threshold scheme in which cheaters are detected with high probability even if they know the secret. The information rate is in this case 1/3 In both schemes, the probability of cheating successfully is a fixed value that is determined by the size of the secret.     

滋长阶小于1的亚纯函数唯一性

§ 1.ＩｎｔｒｏｄｕｃｔｉｏｎａｎｄＭａｉｎＲｅｓｕｌｔｓ　ＢｙａｍｅｒｏｍｏｒｐｈｉｃｆｕｎｃｔｉｏｎｗｅａｌｗａｙｓｍｅａｎａｍｅｒｏｍｏｒｐｈｉｃｆｕｎｃｔｉｏｎｉｎｔｈｅｃｏｍｐｌｅｘｐｌａｎｅＣ .ＷｅａｓｓｕｍｅｔｈａｔｔｈｅｒｅａｄｅｒｉｓｆａｍｉｌｉａｒｗｉｔｈＮｅｖａｎｌｉｎｎａｔｈｅｏｒｙｔｈａｔｃａｎｂｅｆｏｕｎｄ ,ｆｏｒｉｎｓｔａｎｃｅ ,ｉｎ [1 ] .Ｗｅｓａｙｔｈａｔｔｗｏｍｅｒｏｍｏｒｐｈｉｃｆｕｎｃｔｉｏｎｓｆａｎｄ ｇｓｈａｒｅｔｈｅｖａｌｕｅａ∈ Ｃｐｒｏｖｉｄｅｄｔｈ…     

关于亚纯函数的唯一性定理

本文研究亚纯函数的唯一性问题,证明的结果与Ｈ．Ｕｅｄａ的一个工作相关。     

CICC型超导体运行电流的设计

使用超导电性恢复温度模型分析了 CICC型超导体的稳定性与界限电流的关系 ,推导出表明导体运行电流位于下界限电流区域的门限临界电流的表达式 ,给出了 HT- 7U极向场 PF线圈导体的一种设计方案的计算结果。     

Analysis of the M/M/1 Queue with Processor Sharing via Spectral Theory

We show in this paper that the computation of the distribution of the sojourn time of an arbitrary customer in a M/M/1 with the processor sharing discipline (abbreviated to M/M/1 PS queue) can be formulated as a spectral problem for a self-adjoint operator. This approach allows us to improve the existing results for this queue in two directions. First, the orthogonal structure underlying the M/M/1 PS queue is revealed. Second, an integral representation of the distribution of the sojourn time of a customer entering the system while there are n customers in service is obtained.