I-图的可扩性

如果连通图I中任意n条点不交的边都包含在一个完美匹配中,就称I是n-可扩的.证明了真I图I(n,j,k)是1-可扩的;当n≠3j或者3k时,真I-图是2-可扩的.     

Faster Subtree Isomorphism

We study the subtree isomorphism problem: Given trees H and G, find a subtree of G which is isomorphic to H or decide that there is no such subtree. We give an O((k^1.5/log k)n)-time algorithm for this problem, where k and n are the number of vertices in H and G, respectively. This improves over the O(k^1.5n) algorithms of Chung and Matula. We also give a randomized (Las Vegas) O(k^1.376n)-time algorithm for the decision problem.     

Isomorphism in Wavelets

Journal of Fourier Analysis and Applications - Two scaling functions $$\varphi _A$$ and $$\varphi _B$$ for Parseval frame wavelets are algebraically isomorphic, $$\varphi _A \simeq \varphi _B$$, if...     

Isomorphism of spiral polygons

We call two polygonsisomorphic if there is a one-to-one mapping between theirpoints (not vertices) that preserves visibility. In this paper we establish necessary and sufficient conditions for two spiral polygons to be isomorphic, and give anO(n ² ) algorithm to detect such isomorphism. We also show that the continuous graph of visibility on the points of a spiral polygon is an (uncountably infinite) interval graph, and that no other polygons have this property. This research was supported by the Natural Sciences and Engineering Research Council of Canada under Research Grant Number OGP0046218 and a Post-Graduate Scholarship.     

Isomorphism of random walks

We show that any two aperiodic, recurrent random walks on the integers whose jump distributions have finite seventh moment, are isomorphic as infinite measure preserving transformations. The method of proof involved uses a notion of equivalence of renewal sequences, and the “relative” isomorphism of Bernoulli shifts respecting a common state lumping with the same conditional entropy. We also prove an analogous result for random walks on the two dimensional integer lattice.     

Isomorphism is equality

The setting of this work is dependent type theory extended with the univalence axiom. We prove that, for a large class of algebraic structures, isomorphic instances of a structure are equal—in fact, isomorphism is in bijective correspondence with equality. The class of structures includes monoids whose underlying types are “sets”, and also posets where the underlying types are sets and the ordering relations are pointwise “propositional”. For monoids on sets equality coincides with the usual notion of isomorphism from universal algebra, and for posets of the kind mentioned above equality coincides with order isomorphism.     

Isomorphism on Hypergroups

ＩｓｏｍｏｒｐｈｉｓｍｏｎＨｙｐｅｒｇｒｏｕｐｓ钟育彬ＩｓｏｍｏｒｐｈｉｓｍｏｎＨｙｐｅｒｇｒｏｕｐｓ￥ＺｈｏｎＹｕＢｉｎ（Ｄｅｐｔ．ｏｆＭａｔｈｓ．，ＧｕａｎｇｚｈｏｕＴｅａｃｈｅｒｓＣｏｌｌｅｇｅ）Ａｂｓｔｒａｃｔ：Ｔｈｉｓｐｅｐｅｒｇｉｖｅｓｓ...     

超模的同构定理

本文利用模论导出超模的三个同构定理,同时,给出超模的Jordan-Holder定理,最后,探讨了超模的基本关系∈~*,并研究其性质．     

Isomorphism rigidity of commuting automorphisms

Let , and let and be two zero-entropy -actions on compact abelian groups by commuting automorphisms. We show that if all lower rank subactions of and have completely positive entropy, then any measurable equivariant map from to is an affine map. In particular, two such actions are measurably conjugate if and only if they are algebraically conjugate.

     

超环的模糊同构定理

引入超环的正规模糊超理想概念,利用其刻画超环的模糊同构定理.     

Isomorphism of generalized matrix rings

An isomorphism problem is considered for generalized matrix rings with values in a given ring R. An exhaustive answer is given for the case of a commutative domain R and a commutative local ring R.     

Isomorphism of Borel full groups

Suppose that and are Polish groups which act in a Borel fashion on Polish spaces and . Let and denote the corresponding orbit equivalence relations, and and the corresponding Borel full groups. Modulo the obvious counterexamples, we show that .