Electron-diffraction pattern with 'tenfold rotational symmetry' of Al-Fe alloyphase is assumed to be produced by periodic structure. One 3D periodic structure is presentedbased on so-called C polyhedra. The st...Electron-diffraction pattern with 'tenfold rotational symmetry' of Al-Fe alloyphase is assumed to be produced by periodic structure. One 3D periodic structure is presentedbased on so-called C polyhedra. The structure can be used as atomic model to describethe Al-Fe alloy phase. The Fourier transform patterns of the model are in good agreementwith the corresponding electron-diffraction patterns. Several other models with' tenfold symmetry' Fourier transform patterns have briefly been mentioned.展开更多
A new nonclassical crystallographic group (NCG) theoretical system is set up.This system can describe infinite kinds of nonclassical periodic structures,especially for those with locally n-fold rotational symmetries f...A new nonclassical crystallographic group (NCG) theoretical system is set up.This system can describe infinite kinds of nonclassical periodic structures,especially for those with locally n-fold rotational symmetries forbidden by the rules of the classical crystallography. The formal classification of NCGs is given.展开更多
为设计性能较好的伪随机数发生器,提出了一个满足修正的马罗驼(Marotto)定理的新二维离散混沌系统(2DCS)。利用离散广义混沌同步理论和2D-CS构造了一个广义同步混沌系统(2D-GCS);通过一个实数域到整数域的变换设计了一个混沌伪随机数生...为设计性能较好的伪随机数发生器,提出了一个满足修正的马罗驼(Marotto)定理的新二维离散混沌系统(2DCS)。利用离散广义混沌同步理论和2D-CS构造了一个广义同步混沌系统(2D-GCS);通过一个实数域到整数域的变换设计了一个混沌伪随机数生成器(CPRNG);利用美国联邦信息处理标准(federal information processing standards,FIPS)提出的FIPS 140-2检测包分别对CPRNG和RC4算法产生的1000个二进制序列的随机性进行检测,结果均通过了检测。检测结果的平均值和方差对比表明CPRNG和RC4算法产生的伪随机序列随机性能相当,相关性检测结果表明该CPRNG在不同的密钥扰动下产生的密钥各组序列几乎完全独立,设计的CPRNG能产生性能良好的伪随机数。展开更多
文摘Electron-diffraction pattern with 'tenfold rotational symmetry' of Al-Fe alloyphase is assumed to be produced by periodic structure. One 3D periodic structure is presentedbased on so-called C polyhedra. The structure can be used as atomic model to describethe Al-Fe alloy phase. The Fourier transform patterns of the model are in good agreementwith the corresponding electron-diffraction patterns. Several other models with' tenfold symmetry' Fourier transform patterns have briefly been mentioned.
文摘A new nonclassical crystallographic group (NCG) theoretical system is set up.This system can describe infinite kinds of nonclassical periodic structures,especially for those with locally n-fold rotational symmetries forbidden by the rules of the classical crystallography. The formal classification of NCGs is given.
文摘为设计性能较好的伪随机数发生器,提出了一个满足修正的马罗驼(Marotto)定理的新二维离散混沌系统(2DCS)。利用离散广义混沌同步理论和2D-CS构造了一个广义同步混沌系统(2D-GCS);通过一个实数域到整数域的变换设计了一个混沌伪随机数生成器(CPRNG);利用美国联邦信息处理标准(federal information processing standards,FIPS)提出的FIPS 140-2检测包分别对CPRNG和RC4算法产生的1000个二进制序列的随机性进行检测,结果均通过了检测。检测结果的平均值和方差对比表明CPRNG和RC4算法产生的伪随机序列随机性能相当,相关性检测结果表明该CPRNG在不同的密钥扰动下产生的密钥各组序列几乎完全独立,设计的CPRNG能产生性能良好的伪随机数。
