Degree Type

Dissertation

Date of Award

2012

Degree Name

Doctor of Philosophy

Department

Mathematics

First Advisor

Sung Song

Abstract

We explore directed strongly regular graphs (DSRGs) and their connections to association schemes and finite incidence structures. More specically, we study flags and antiflags of finite

incidence structures to provide explicit constructions of DSRGs. By using this connection between the finite incidence structures and digraphs, we verify the existence and non-existence of $1\frac{1}{2}$-designs with certain parameters by the existence and non-existence of corresponding digraphs, and vice versa. We also classify DSRGs of given parameters according to isomorphism classes. Particularly, we examine the actions of automorphism groups to provide explicit

examples of isomorphism classes and connection to association schemes. We provide infinite families of vertex-transitive DSRGs in connection to non-commutative association schemes.

These graphs are obtained from tactical configurations and coset graphs.

Copyright Owner

Oktay Olmez

Language

en

File Format

application/pdf

File Size

85 pages

Included in

Mathematics Commons

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