Degree Type
Dissertation
Date of Award
1983
Degree Name
Doctor of Philosophy
Department
Computer Science
Abstract
A hierarchy of data structures, called the hypertree hierarchy, is presented which has strings and trees as its smallest two elements. A generalized frontiering operation is presented. Grammars, automata and regular expressions are extended to this hierarchy. These are shown to be equivalent and the resulting languages are called regular. This leads to a hierarchy of regular languages on the hypertree hierarchy. These are projected onto the set of strings by the frontier operation resulting in a true hierarchy of string languages. This hierarchy is called the (IO) algebraic language hierarchy. It has regular languages, context free languages and macro languages as its first three levels. It is contained in the set of context sensitive languages but is not equal to it. Other characterizations are presented.
DOI
https://doi.org/10.31274/rtd-180813-8555
Publisher
Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/
Copyright Owner
William Allen Baldwin
Copyright Date
1983
Language
en
Proquest ID
AAI8407048
File Format
application/pdf
File Size
345 pages
Recommended Citation
Baldwin, William Allen, "Hypertrees: a study in language specification " (1983). Retrospective Theses and Dissertations. 8449.
https://lib.dr.iastate.edu/rtd/8449