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1.
A Cayley map is a Cayley graph embedded in an orientable surface such that. the local rotations at every vertex are identical. In this paper, balanced regular Cayley maps for cyclic groups, dihedral groups, and generalized quaternion groups are classified.  相似文献   
2.
一类广义Bent型S-Box的构造   总被引:1,自引:0,他引:1  
S-box是密码理论与实践中十分重要的一种装置 ,它的密码性能由其分量函数所决定 .于是 ,选择适当的分量函数来构造 S-box就成了一个重要的研究课题 .在一定意义上 ,Bent函数是最优良的密码函数 .本文通过函数序列半群和置换群来构造其任何非零线性组合为 Bent函数与线性函数之和的函数组 ,从而可由 Bent函数构造出具有高度非线性度和其他良好性状的 S-box  相似文献   
3.
验证力的平行四边形定则实验是最基本的实验之一.过去的教学表明,学生在物体共点力的合成与分解,力的平衡,以及物体受力分析等方面出现的问题,追究其根源,就是教师没有重视验证力的平行四边形定则实验.教师借故弹簧秤数量不足而且误差大,所以只做了演示实验或定性说明,导致学生对于力的矢量性理解不深刻.  相似文献   
4.
本文研究和讨论了作为多输出函数的N级模2~M背包变换平衡特性,给出了N级模2~M平衡背包变换的结构、计数和函数性质,指出了N级模2~M平衡背包变换本身作为密码变换函数存在着除了第M路外,所有各路的输出函数都是不完全函数的弱点,从而得出了背包变换是密码学弱函数的结论.  相似文献   
5.
Large-scale non-equilibrium molecular dynamics simulations are used to investigate the ejection of the metal under a shock loading. The present work focus on the dynamic process of ejection from the metal Cu and Al surface groove under shock loading, using parallel MD implementation and the Morse potential. The ejected mass coefficient and the size distribution of ejected particles (cluster for atoms) are investigated with changes of the half-angle or the depth of groove and shock strength.  相似文献   
6.
Some consistency problems existing in continuum field theories are briefly reviewed. Three arts of consistency problems are clarified based on the renewed basic laws for polar continua. The first art discusses the consistency problems between the basic laws for polar continua. The second art discusses the consistency problems between the basic laws for polar continua and for other nonpolar continua. The third art discusses the consistency problems between the basic laws for micropolar continuum theories and the dynamical equations for rigid body. The results presented here can help us to get a deeper understanding the structure of the basic laws for various continuum theories and the interrelations between them. In the meantime, these results obtained show clearly that the consistency problems could not be solved in the framework of traditional basic laws for continuum field theories.  相似文献   
7.
肖静  邓振波 《发光学报》2017,38(5):601-605
设计了基于Bphen∶LiF、Al和MoO3的杂化电荷注入层,并将其应用于有机电致发光器件中。实验研究表明,这种杂化层作为阳极修饰层是非常有效的,它可以增加器件中载流子注入的平衡性,提高器件的性能。相对参考器件,基于杂化阳极修饰层的电致发光器件的最大电流效率和最大功率效率均提高1.3倍左右。我们对器件性能及其提高的机理进行了分析。  相似文献   
8.
In this paper, the authors analyze the stability of a kind of discrete-time Hopfield neural network with asymptotical weighted matrix, which can be expressed as the product of a positive definite diagonal matrix and a symmetric matrix. We obtain that it has asymptotically stable equilibriums if the network is updated asynchronously, and asymptotically stable equilibriums or vibrating final stage with 2 period if updated synchronously. To prove these, Lassale's invariance principle in difference equation is applied.  相似文献   
9.
红塔系列香烟月均价格的时间序列分析   总被引:3,自引:1,他引:2  
本文利用时间序列的方法,对带有删失数据的红塔烟草系列的月度平均价格进行了统计分析。得到了一定置信水平下的时间序列模型。为进一步的定性分析提供了模型基础。  相似文献   
10.
We present first-principles studies on the transport properties of small sificon and aluminium clusters: Al2, Si2, Al4 and AlSi sandwiched between two Al (100) electrodes. The variation of the equilibrium conductance as a function of contact distance for these two-probe systems is probed. Our results show that the transport properties are dependent on both the specific nanostructure and the separation distance between the central molecule and the electrodes. For equilibrium transport properties, the clusters with the similar structure show similar transmission spectra at large distances, the small difference can be explained by the electron filling. For current-voltage characteristics, all the clusters show the metallic behaviour at lower bias, however very different non-linear behaviour can be observed at higher bias. For AlSi and Al2, when the distance between the central cluster and the electrodes is 3.5 A, large negative differential resistance (NDR) can be found in the bias range 0.8V~1.4V.  相似文献   
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