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991.
992.
Babushri Srinivas Kedukodi Syam Prasad Kuncham Satyanarayana Bhavanari 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2009,13(10):933-944
In this paper, we present the notions of equiprime fuzzy ideal, 3-prime fuzzy ideal and c-prime fuzzy ideal of a nearring.
We characterize these fuzzy ideals using level subsets and fuzzy points. If f: N → M is an onto nearring homomorphism, we show that the map defines a one-to-one correspondence between the set of all f-invariant (alternatively with sup property) equiprime (3-prime and c-prime, respectively) fuzzy ideals of N and the set of all equiprime (3-prime and c-prime, respectively) fuzzy ideals of M. Finally, we define fuzzy cosets determined by generalized fuzzy ideals; obtain fundamental results and isomorphism theorems. 相似文献
993.
Roughness based on fuzzy ideals 总被引:1,自引:0,他引:1
B. Davvaz 《Information Sciences》2006,176(16):2417-2437
The theory of rough set, proposed by Pawlak and the theory of fuzzy set, proposed by Zadeh are complementary generalizations of classical set theory. Many sets are naturally endowed with two binary operations: addition and multiplication. One concept which does this is a ring. This paper concerns a relationship between rough sets, fuzzy sets and ring theory. It is a continuation of ideas presented by Kuroki and Wang [N. Kuroki, P.P. Wang, The lower and upper approximations in a fuzzy group, Inform. Sci. 90 (1996) 203-220]. We consider a ring as a universal set and we assume that the knowledge about objects is restricted by a fuzzy ideal. In fact, we apply the notion of fuzzy ideal of a ring for definitions of the lower and upper approximations in a ring. Some characterizations of the above approximations are made and some examples are presented. 相似文献
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Let J be a strongly stable monomial ideal in S=K[x0,…,xn] and let Mf(J) be the family of all homogeneous ideals I in S such that the set of all terms outside J is a K-vector basis of the quotient S/I. We show that an ideal I belongs to Mf(J) if and only if it is generated by a special set of polynomials, the J-marked basis of I, that in some sense generalizes the notion of reduced Gröbner basis and its constructive capabilities. Indeed, although not every J-marked basis is a Gröbner basis with respect to some term order, a sort of reduced form modulo I∈Mf(J) can be computed for every homogeneous polynomial, so that a J-marked basis can be characterized by a Buchberger-like criterion. Using J-marked bases, we prove that the family Mf(J) can be endowed, in a very natural way, with a structure of an affine scheme that turns out to be homogeneous with respect to a non-standard grading and flat in the origin (the point corresponding to J), thanks to properties ofJ-marked bases analogous to those of Gröbner bases about syzygies. 相似文献
996.
The use of thresholding to separate objects in an image is analyzed in the light of a notion that ‘objects are in the eye of the beholder’, i.e. the existence of objects in an image is subjective rather than objective. Interpretation of the term ‘semantic’ as an association of an observed entity with an (other) entity which can be used for communication, is combined with Whorf's hypothesis on influence of language on reasoning, to yield a thresholding method. The method is based on minimizing the ambiguity which results from the different contexts (local and global) in which grey levels are classified as dark or bright. Examples are supplied and compared to thresholds which are optimal in the L2 norm. 相似文献
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近似理想格上的全同态加密方案 总被引:1,自引:0,他引:1
构造高效、安全的全同态加密方案目前仍然是一个公开问题.通过扩展近似GCD到近似理想格的方法,首先构造一个基于整数上部分近似理想格问题(PAILP)的有点同态加密方案,并使用Gentry的引导技术将其转换到全同态加密方案.归约有点同态加密方案的安全性到求解部分近似理想格问题;其次,构造基于PAILP的批全同态加密方案和基于近似理想格(AILP)的全同态加密方案;最后,实现基于PAILP/AILP的全同态加密方案,并通过计算实验,其结果表明,所提方案比已有方案性能更好. 相似文献
1000.