Results 21 to 30 of about 1,288,795 (193)
Isomorphs of a class of Queueing systems [PDF]
International Journal of Mathematics and Mathematical Sciences, 1979 Restricted isomorphism between two queueing systems implies that they have equivalent distribution function for at least one (but not all) output elements (e.g. waiting time, queue size, idle time, etc.). Quasi‐isomorphism implies an approximate equivalence.
A. Ghosal, Sudhir Madan
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Isomorphism classes and stably isomorphisms of double Danielewski varieties
The interest in Danielewski varieties arose from the study of the Cancellation Problem. In this paper, we study the isomorphism classes and stably isomorphisms of double Danielewski varieties, and show that they are counterexamples of the Cancellation Problem.
Sun, Xiaosong, Zeng, Shuai
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The Isomorphism Problem on Classes of Automatic Structures [PDF]
2010 25th Annual IEEE Symposium on Logic in Computer Science, 2010 Automatic structures are finitely presented structures where the universe and all relations can be recognized by finite automata. It is known that the isomorphism problem for automatic structures is complete for $Σ^1_1$; the first existential level of the analytical hierarchy.
Dietrich Kuske +2 more
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The Structure of Local Rings with Singleton Basis and Their Enumeration
Mathematics, 2022 A local ring is an associative ring with unique maximal ideal. We associate with each Artinian local ring with singleton basis four invariants (positive integers) p,n,s,t.
Yousef Alkhamees, Sami Alabiad
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Equivalences between isomorphism classes on infinite graphs [PDF]
, 1992 summary:The paper studies some equivalence relations between isomorphism classes of countable graphs which correspond in a certain sense to various distances between isomorphism classes of finite ...
Zelinka, Bohdan
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Subgraph Isomorphism on Graph Classes that Exclude a Substructure [PDF]
Algorithmica, 2020 We study Subgraph Isomorphism on graph classes defined by a fixed forbidden graph. Although there are several ways for forbidding a graph, we observe that it is reasonable to focus on the minor relation since other well-known relations lead to either trivial or equivalent problems.
Hans L. Bodlaender +6 more
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The isomorphism class of C0 is not Borel [PDF]
Israel Journal of Mathematics, 2019 We show that the class of all Banach spaces which are isomorphic to $ c_{0} $ is a complete analytic set with respect to the Effros Borel structure of separable Banach spaces. The proof employs a recent Bourgain-Delbaen construction by Argyros, Gasparis and Motakis.
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On distances between isomorphism classes of graphs [PDF]
, 1991 summary:In 1986, Chartrand, Saba and Zou [3] defined a measure of the distance between (the isomorphism classes of) two graphs based on 'edge rotations'. Here, that measure and two related measures are explored.
Goddard, Wayne +3 more
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Generation of colored graphs with isomorphism rejection [PDF]
Известия Саратовского университета. Новая серия: Математика. Механика. Информатика, 2021 In the article we consider graphs whose vertices or edges are colored in a given number of colors — vertex and edge colorings. The study of colorings of graphs began in the middle of the 19th century, but the main attention is paid to proper ...
Razumovsky, Peter Vladimirovich +1 more
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Isomorphism Classes of A-Hypergeometric Systems [PDF]
Compositio Mathematica, 2001 Given a finite set A of integral vectors and a parameter vector, Gel'fand, Kapranov, and Zelevinskii defined a system of differential equations, called an A - hypergeometric (or a GKZ ...
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