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61.
有序二叉决策图在防火墙规则库设计中的应用 总被引:2,自引:0,他引:2
在防火墙规则库的设计中利用有序二叉决策图(ordered binary decision diagram,OBDD)来表示防火墙的访问控制规则集,改变了传统的顺序存储规则的规则库设计方法,以增加预处理时间为代价,有效地提高了规则的匹配速度,从而提高了防火墙的性能及其安全性. 相似文献
62.
戴小花 《南昌大学学报(理科版)》2005,29(3):219-223
定义了V-赋值的比较,给出了定理2.2:若Aω是关于Av的中间集,则(ω,A)≥(v,Γ)。研究了布尔V-幺半群,得到:若Γ为布尔V-幺半群,则(v,Γ)是形式有限的。证明了:设(B,M)为环R的非浅显Manis赋值对,则B为实环当且仅当R为实环。进一步,给出一个反例用来说明,命题2对于V-赋值对而言未必成立。 相似文献
63.
Nested spaces of multivariate periodic functions forming a non-stationary multiresolution analysis are investigated. The scaling
functions of these spaces are fundamental polynomials of Lagrange interpolation on a sparse grid. The approach based on Boolean
sums leads to sample and wavelet spaces of significantly lower dimension and good approximation order. The algorithms for
complete decomposition and reconstruction are of simple structure and low complexity.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
64.
分析了布尔偏导数与布尔差分的关系,给出了基于布尔偏导数的组合电路双故障测试集的方程,引入了奇集合的概念.在此基础上提出了基于布尔偏导数的组合电路双故障检测的新方法.实例表明该方法具有思路清晰、操作简单及易于掌握的优点. 相似文献
65.
K. Keremedis 《Algebra Universalis》1998,39(3-4):163-169
We show that the axiom of choice AC is equivalent to the statement Any quotient group of any abelian group has a selector. We also show that the multiple choice axiom MC is equivalent to the assertion: Any filter
in any Boolean ring
has a well ordered filterbase.
Received October 3, 1996; accepted in final form May 1, 1998. 相似文献
66.
Milo S. Kurili 《Mathematical Logic Quarterly》2004,50(6):594-602
If κ is an infinite cardinal, a complete Boolean algebra B is called κ‐supported if for each sequence 〈bβ : β < κ〉 of elements of B the equality α<κ β>α bβ = equation/tex2gif-inf-5.gif β∈A bβ holds. Combinatorial and forcing equivalents of this property are given and compared with the other forcing related properties of Boolean algebras (distributivity, caliber, etc.). The set of regular cardinals κ for which B is not κ‐supported is investigated. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
67.
Regina Aragn 《Mathematical Logic Quarterly》1995,41(4):485-504
We consider the theory Thprin of Boolean algebras with a principal ideal, the theory Thmax of Boolean algebras with a maximal ideal, the theory Thac of atomic Boolean algebras with an ideal where the supremum of the ideal exists, and the theory Thsa of atomless Boolean algebras with an ideal where the supremum of the ideal exists. First, we find elementary invariants for Thprin and Thsa. If T is a theory in a first order language and α is a linear order with least element, then we let Sentalg(T) be the Lindenbaum-Tarski algebra with respect to T, and we let intalg(α) be the interval algebra of α. Using rank diagrams, we show that Sentalg(Thprin) ? intalg(ω4), Sentalg(Thmax) ? intalg(ω3) ? Sentalg(Thac), and Sentalg(Thsa) ? intalg(ω2 + ω2). For Thmax and Thac we use Ershov's elementary invariants of these theories. We also show that the algebra of formulas of the theory Tx of Boolean algebras with finitely many ideals is atomic. 相似文献
68.
S.Winker在文〔1〕中给出了Robbins代数成为Boolean代数的一个较弱的条件。本文将讨论Heyting代数成为Boolean代数的条件,我们发现Heying代数成为Boolean代数的条件与Robbins代数成为Boolean代数的条件相似,从而提示了Heyting代数与Robbins代数之间具有一定的关系。 相似文献
69.
70.
This paper concerns classification by Boolean functions. We investigate the classification accuracy obtained by standard classification techniques on unseen points (elements of the domain, {0,1}n, for some n) that are similar, in particular senses, to the points that have been observed as training observations. Explicitly, we use a new measure of how similar a point x∈{0,1}n is to a set of such points to restrict the domain of points on which we offer a classification. For points sufficiently dissimilar, no classification is given. We report on experimental results which indicate that the classification accuracies obtained on the resulting restricted domains are better than those obtained without restriction. These experiments involve a number of standard data-sets and classification techniques. We also compare the classification accuracies with those obtained by restricting the domain on which classification is given by using the Hamming distance. 相似文献