David Bevan is an English mathematician, computer scientist and software developer.
He is known for Bevan's theorem, which gives the asymptotic enumeration of grid classes of permutations
and for his work on
enumerating the class of permutations avoiding the pattern 1324.
He is also known for devising
weighted reference counting, an approach to computer
memory management
Memory management is a form of resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when ...
that is suitable for use in
distributed systems
A distributed system is a system whose components are located on different networked computers, which communicate and coordinate their actions by passing messages to one another from any system. Distributed computing is a field of computer sci ...
.
Work and research
Bevan is a lecturer in
combinatorics
Combinatorics is an area of mathematics primarily concerned with counting, both as a means and an end in obtaining results, and certain properties of finite structures. It is closely related to many other areas of mathematics and has many appl ...
in the department of
Mathematics and Statistics
Mathematics is an area of knowledge that includes the topics of numbers, formulas and related structures, shapes and the spaces in which they are contained, and quantities and their changes. These topics are represented in modern mathematics ...
at the
University of Strathclyde
The University of Strathclyde ( gd, Oilthigh Shrath Chluaidh) is a public research university located in Glasgow, Scotland. Founded in 1796 as the Andersonian Institute, it is Glasgow's second-oldest university, having received its royal chart ...
.
He has degrees in mathematics and computer science from the
University of Oxford
, mottoeng = The Lord is my light
, established =
, endowment = £6.1 billion (including colleges) (2019)
, budget = £2.145 billion (2019–20)
, chancellor ...
and a degree in theology from the
London School of Theology
The London School of Theology (LST), formerly London Bible College, is a British interdenominational evangelical theological college based in Northwood within the London Borough of Hillingdon.
History
During the 1930s A. J. Vereker, secreta ...
. He received his PhD in mathematics from
The Open University
The Open University (OU) is a British public research university and the largest university in the United Kingdom by number of students. The majority of the OU's undergraduate students are based in the United Kingdom and principally study off- ...
in 2015; his thesis, ''On the growth of permutation classes'', was supervised by Robert Brignall.
In 1987, as a research scientist at
GEC's
Hirst Research Centre
The Hirst Research Centre, also known as the GEC Hirst Research Centre or GEC Research Laboratories, was established in 1919 at Wembley, Middlesex, by the General Electric Company.
History
Formally opened in 1923, the site at East Lane, Wembley ...
in Wembley, he developed an approach to computer
memory management
Memory management is a form of resource management applied to computer memory. The essential requirement of memory management is to provide ways to dynamically allocate portions of memory to programs at their request, and free it for reuse when ...
, called
weighted reference counting, that is suitable for use in
distributed systems
A distributed system is a system whose components are located on different networked computers, which communicate and coordinate their actions by passing messages to one another from any system. Distributed computing is a field of computer sci ...
.
During the 1990s, while working for the
Summer Institute of Linguistics
SIL International (formerly known as the Summer Institute of Linguistics) is an evangelical Christian non-profit organization whose main purpose is to study, develop and document languages, especially those that are lesser-known, in order to ex ...
in
Papua New Guinea
Papua New Guinea (abbreviated PNG; , ; tpi, Papua Niugini; ho, Papua Niu Gini), officially the Independent State of Papua New Guinea ( tpi, Independen Stet bilong Papua Niugini; ho, Independen Stet bilong Papua Niu Gini), is a country i ...
, he developed a computer program, called ''FindPhone'', that was widely used by field linguists to analyse phonetic data in order to understand the
phonology
Phonology is the branch of linguistics that studies how languages or dialects systematically organize their sounds or, for sign languages, their constituent parts of signs. The term can also refer specifically to the sound or sign system of a ...
of
minority languages
A minority language is a language spoken by a minority of the population of a territory. Such people are termed linguistic minorities or language minorities. With a total number of 196 sovereign states recognized internationally (as of 2019) and ...
.
While employed by
Pitney Bowes
Pitney Bowes Inc. is an American technology company most known for its postage meters and other mailing equipment and services, and with expansions into e-commerce, software, and other technologies. The company was founded by Arthur Pitney, who i ...
, he was a major contributor to the development of the
FreeType text rendering library.
Bevan's mathematical research has concerned areas of
enumerative combinatorics
Enumerative combinatorics is an area of combinatorics that deals with the number of ways that certain patterns can be formed. Two examples of this type of problem are counting combinations and counting permutations. More generally, given an infin ...
, particularly in relation to
permutation classes.
He established that the growth rate of a monotone grid class of permutations is equal to the square of the
spectral radius
In mathematics, the spectral radius of a square matrix is the maximum of the absolute values of its eigenvalues. More generally, the spectral radius of a bounded linear operator is the supremum of the absolute values of the elements of its spectru ...
of a related
bipartite graph
In the mathematical field of graph theory, a bipartite graph (or bigraph) is a graph whose vertices can be divided into two disjoint and independent sets U and V, that is every edge connects a vertex in U to one in V. Vertex sets U and V are ...
.
He has also determined bounds on the growth rate of
the class of permutations avoiding the pattern 1324.
In the Acknowledgements sections of his journal articles, he often includes the Latin phrase
Soli Deo gloria.
Selected publications
*
*
*
*
References
External links
David Bevan's page at the University of Strathclyde
{{DEFAULTSORT:Bevan, David
Combinatorialists
21st-century English mathematicians
English mathematicians
English computer scientists
Academics of the University of Strathclyde
Alumni of The Queen's College, Oxford
Alumni of the London School of Theology
Alumni of the Open University
1961 births
Living people