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201.
R. G. Stoneham 《BIT Numerical Mathematics》1970,10(4):481-500
In the computing literature, there are few detailed analytical studies of the global statistical characteristics of a class of multiplicative pseudo-random number generators.We comment briefly on normal numbers and study analytically the approximately uniform discrete distribution or (j,)-normality in the sense of Besicovitch for complete periods of fractional parts {x
0
1
i
/p} on [0, 1] fori=0, 1,..., (p–1)p–1–1, i.e. in current terminology, generators given byx
n+1
1
x
n mod p wheren=0, 1,..., (p–1)p
–1–1,p is any odd prime, (x
0,p)=1,
1 is a primitive root modp
2, and 1 is any positive integer.We derive the expectationsE(X, ),E(X
2, ),E(X
nXn+k); the varianceV(X, ), and the serial correlation coefficient k. By means of Dedekind sums and some results of H. Rademacher, we investigate the asymptotic properties of k for various lagsk and integers 1 and give numerical illustrations. For the frequently used case =1, we find comparable results to estimates of Coveyou and Jansson as well as a mathematical demonstration of a so-called rule of thumb related to the choice of
1 for small k.Due to the number of parameters in this class of generators, it may be possible to obtain increased control over the statistical behavior of these pseudo-random sequences both analytically as well as computationally. 相似文献
202.
203.
本文对提出的最大乘积型Fuzzy文法与最大乘积型Fuzzy自动机的关系作了详细讨论,得出了两个重要的结论。即:由给定的最大乘积型Fuzzy正规文法可构造一个最大乘积型Fuzzy自动机使得二者接受的语言集相同,反之亦然。从而达到自动识别语言的目的。 相似文献
204.
205.
Neutron skin thickness of 90Zr and symmetry energy constrained by charge exchange spin-dipole excitations 下载免费PDF全文
The charge exchange spin-dipole (SD) excitations of \begin{document}$ ^{90} $\end{document} ![]()
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Zr are studied using the Skyrme Hartee-Fock plus proton-neutron random phase approximation with SAMi-J interactions. The experimental value of the model-independent sum rule obtained from the SD strength distributions of \begin{document}$ ^{90} $\end{document} ![]()
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Zr(p, n)\begin{document}$ ^{90} $\end{document} ![]()
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Nb and \begin{document}$ ^{90} $\end{document} ![]()
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Zr(n, p)\begin{document}$ ^{90} $\end{document} ![]()
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Y is used to deduce the neutron skin thickness. The neutron skin thickness \begin{document}$ \Delta r_{np} $\end{document} ![]()
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of \begin{document}$ ^{90} $\end{document} ![]()
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Zr is extracted as \begin{document}$ 0.083\pm0.032 $\end{document} ![]()
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fm, which is similar to the results of other studies. Based on the correlation analysis of the neutron skin thickness \begin{document}$ \Delta r_{np} $\end{document} ![]()
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and the nuclear symmetry energy J as well as its slope parameter L, a constraint from the extracted \begin{document}$ \Delta r_{np} $\end{document} ![]()
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leads to the limitation of J to \begin{document}$ 29.2 \pm 2.6 $\end{document} ![]()
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MeV and L to \begin{document}$ 53.3 \pm 28.2 $\end{document} ![]()
![]()
MeV. 相似文献
206.
利用锥理论和非对称迭代法,讨论了随机单调减算子的随机不动点的存在唯一性,同时给出了迭代序列收敛于解的误差估计,改进和推广了某些已知结果. 相似文献
207.
以正则环为桥梁,研究了morphic-环与SF-环之间的关系.主要工作如下:(i)研究了SF-环成为morphic-环的若干条件;(ii)讨论了在一定条件下SF-环与morphic-环的等价性;(iii)给出了利用morphic-环对半单环在约化条件下的一个刻划. 相似文献
208.
209.
Daniel K. Benvenuti 《Discrete Mathematics》2010,310(21):2841-2846
A graph G on n vertices is said to be separable cost constant Hamiltonian (SC-Hamiltonian) if and only if G is Hamiltonian and for any cost matrix C=(c(i,j)) associated with G where all tours have the same cost, there exist vectors a=(a1,…,an) and b=(b1,…,bn) such that . In this paper we show that for symmetric digraphs strong Hamiltonicity is a necessary condition for SC-Hamiltonicity. As a surprising consequence, we prove that the symmetric digraph obtained from an undirected SC-Hamiltonian graph by edge duplication need not be SC-Hamiltonian. This settles a conjecture of Kabadi and Punnen. We then show that an undirected graph on an even number of nodes having an edge that appears in every Hamiltonian cycle cannot be SC-Hamiltonian. Using this we establish that multiple subdivision of an edge need not preserve SC-Hamiltonicity, disproving a previous claim. Further, we identify other necessary conditions for SC-Hamiltonicity and obtain new classes of SC-Hamiltonian graphs. 相似文献
210.
This note is devoted to introduce a new concept of conditionally dominated random variables.Under suitable restrict conditions,a general strong law of large numbers for arbitrary continuous random variables is obtained. 相似文献