__Curriculum Vita__

**James A. Davis**

2214 Grainmill Court

Richmond, VA 23233

(804) 289-8094 (W)

(804) 747-5858 (H)

**EDUCATION:**

Ph.D. Mathematics, University of Virginia, August, 1987.
Dissertation: "Difference sets in abelian 2-groups";

Advisor: Dr. Harold Ward.

B.S. Mathematics with Honors, Magna cum laude, Lafayette
College, May, 1983.

**EMPLOYMENT:**

Professor,
University of Richmond, 2001-Present.

Associate Professor, University of Richmond, 1994-2001.

Assistant Professor, University of Richmond, 1988-1994.

Visiting Assistant Professor, Lafayette College, August 1987-1988.

Teaching Assistant, University of Virginia, August 1983-1987.

Summer Actuary
Intern, Provident Mutual Life Insurance Company, Summer
of 1982.

**DESCRIPTION
OF RESEARCH:**

Use of
algebraic and number theoretic tools to construct combinatorial structures in
Design Theory and Coding

Theory.

**RECENT
PUBLICATIONS OF NOTE:**

The
following selection of papers illustrates publications of note over the past
few years. A complete list of

publications
is included later in the Curriculum Vita.

**A Unifying
Construction for Difference Sets, with J.Jedwab,
Journal of Combinatorial Theory, Series A,**

**Vol. 80
No.1, 13-78, Oct. 1997.**

The
following review appeared in Math Reviews MR 98g#05021:

The paper under
review clearly ranks as one of the most important papers in the general area of
difference sets

ever
written. I will just mention the most striking results that make it important:
It contains the first new

parameter
family of difference sets found since 1977. It gives a unifying theory which
allows one to produce a

difference
set with $(\nu,n)>1$ in
every abelian group which is known to contain such a
difference set. Not

only was
this true at the time of writing the paper, but it also holds for the new
families of difference sets which

were
subsequently discovered by Y. Q. Chen [Finite Fields Appl. 3 (1997), no. 3,
234--256 1459826; Des.

Codes Cryptogr. 13 (1998), no. 3, 247--250
1601576]. It characterises a certain class of groups
containing

McFarland
difference sets. It allows a transparent treatment of the family of Hadamard difference sets, whereas

the best
previous description (in terms of binary arrays and binary supplementary
quadruples) was still rather

cumbersome.
In particular, the celebrated characterization theorem for those abelian 2-groups which contain a

difference
set (a problem which took decades to settle) becomes a trivial corollary. It
gives a unified way of

constructing
semiregular relative difference sets in virtually all
the known cases, and it gives many new

examples.

Reviewer:
Jungnickel, Dieter (D-AGSB)

**Peak-to-mean
power control in OFDM, Golay complementary sequences
and Reed-Muller codes, with**

**J.Jedwab****, IEEE Transactions on Information Theory, Vol. 45,
2397-2417, 1999.**

OFDM is a
proposed transmission scheme designed to provide more reliable and quicker
communication

between
mobile devices. This paper demonstrates that the use of Golay
complementary sequences

simultaneously
controls the required transmission power and provides efficient
error-correcting capabilities

through the
use of Reed-Muller codes. Also addressed in the paper are flexible
implementation possibilities

obtained by
trading off code rate, power control, and error correction capability.
The problems considered in

this paper
arose during my sabbatical year 1995-96 at Hewlett-Packard Laboratories, and it
illustrates the

usefulness
of theoretical mathematics in answering applied problems in communication
engineering.

**Hadamard**** Difference Sets in Nonabelian 2-Groups, with J.Iiams,
Journal of Algebra, 199, 62-87, 1998.**

This paper
uses representation theory to construct Hadamard difference sets in nonabelian
2-groups. This

collection
of difference sets has the property that the asymptotic value of the exponent
is 2^(3t+2) for a group

of order
2^(4t+2). For abelian groups of order 2^(4t+2), the exponent is bounded by 2^(2t+2), so these

examples
clearly demonstrate that nonabelian groups will allow
difference sets with very different algebraic

properties
than their abelian counterparts. In addition,
this paper provides tools for using representation theory

to identify
subsets which will have desirable properties for constructing difference sets.

**New Families of Semi-Regular Relative Difference Sets, with J.Jedwab and M.Mowbray, Designs,
Codes,**

**and
Cryptography 13, 131-146, 1998.**

This paper
combines direct product difference sets from projective planes with relative
difference sets in

2-groups to
construct relative difference sets in larger groups. These examples
include some of the first

examples in
the literature of large forbidden subgroup semi-regular relative difference
sets in groups whose

order is not
a prime power. Discussing semi-regular relative difference sets in
general, A.Pott wrote in "A

survey of
relative difference sets", *Groups, Difference Sets, and the Monster*,
(K.T.Arasu et. al., eds.),

195-232, de Gruyter, New York, 1996: "It is, in my opinion,
one of the most interesting questions about

relative
difference sets to find all possible groups G which contain such a difference
set ..." This paper is

of interest
because the family of combinatorial objects constructed had not even been
discovered at the

time Pott
wrote his survey.

**Constructions
of Low Rank Relative Difference Sets in 2-groups Using Galois Rings, with
Q.Xiang, Finite**

**Fields
and their Applications 6, 130-145, 2000.**

Galois Rings
have been powerful tools over the past few years in constructing designs and
codes with good

properties.
This paper demonstrates that Galois Rings can be used to construct relative
difference sets in groups

with lower
rank than any previous constructions. The best known previous results
required a rank of 2t for a

group of
order 2^(3t) and forbidden subgroup of order 2^t, and
this paper only requires a rank of (3/2)t for the

same
parameters. In addition, we use results from quadratic forms to compute
the exact value for a parameter

in the
Galois Ring, and this allows us to determine the exact range of parameters of
the partial difference sets in

the Galois
Ring constructed by Y.Q.Chen, D.K.Ray-Chaudhuri,
and Q.Xiang in "Constructions of partial

difference
sets using Galois rings, II", *J. Combin.Theory Ser. A*, 76, 179-196,
1996.

**RECENT
PRESENTATIONS OF NOTE:**

The
following selection of presentations illustrates talks of note over the past
five years. A complete list of

presentations
is included later in the Curriculum Vita.

**A Unifying
Construction for Difference Sets, parts 1 and 2, NATO conference on difference
sets,**

**sequences,
and their correlation properties, Bad Windsheim,
Germany, August 4 & 5, 1998**

These two
hour-long invited talks were designed to provide an introduction to my joint
work

with J.
Jedwab. Approximately 75 experts and students in the audience.

**Golay**** complementary sequences and Reed-Muller codes, NATO conference on
difference sets, sequences,**

**and their
correlation properties, Bad Windsheim, Germany,
August 6, 1998**

This one
hour lecture gave an overview of my joint work with J.Jedwab
to approximately 75 experts and

students in
the audience.

**From the Kirkman schoolgirl problem to error
correcting codes: different views of difference sets, The**

**University
of Wales at Aberystwyth colloquium, May, 1996.**

This
colloquium lecture presented topics from several papers, indicating the
connections between difference

sets and
coding theory.

**Denniston**** Partial Difference Sets, The
National University of Singapore, June, 2000.**

This seminar
talk presented my joint work with Qing Xiang, covering the connections between Hadamard

difference
sets, Singer difference sets, and Denniston partial difference sets.

**UNDERGRADUATE
HONORS THESES DIRECTED:**

Crossover
property of the nonperiodic autocorrelation function
of quaternary sequences, Michael Pohl, 2007.

Relative
difference sets in 2-groups: a group cohomological viewpoint, Brian Wyman,
2005.

Difference sets, symmetric
designs, and coding theory: a look at the incidence matrices for several difference sets,

Kate
Nieswand, 2000.

On some new constructions of difference sets, Sarah Spence, 1997.

Generalizations of the mod4 construction of the Nordstrom-Robinson Code,
Tim Frey, 1995.

Topics in cyclotomic and quadratic fields, Pam
Mellinger, 1993.

A new view of
McFarland difference sets, John Polhill, 1993.

**SUMMER
RESEARCH** **PROJECTS DIRECTED:**

Sequences with the shared autocorrelation property,** **Corneliu
Bodea, Calina Copos, Matt Der, David Oneal, Summer 2008.

Sponsored by the National Science Foundation.

Sequences with the shared autocorrelation property, Calina Copos, Matt
Der, David Oneal, and Lauren Vanson,

Summer 2007. Sponsored by the National Science Foundation.

Reversible difference sets in 2-groups, Ryan Daut, Summer
2005. Sponsored by the National Security Agency.

A search for new
partial difference sets, Peter Magliaro and Adam Weaver, Summer
2003. Sponsored by the

National Security Agency.

Partial
difference sets in new groups, Tiffany Broadbent and Ed Kenney, Summer 2002. Sponsored by the
University

of Richmond Undergraduate Research Committee, Collaborative Research
Grant.

Difference sets
in 2-groups and their associated codes,Mohammed
Abouzaid and Jamie Bigelow, Summer, 2000.

Sponsored by Hewlett-Packard.

Construction of
New Asymptotic Classes of Binary Sequences Based on Existing Asymptotic
Classes, Anthony

Kirilusha and Ganesh Narayanaswamy,
summer 1999. Sponsored by Hewlett-Packard.

Intersections of
Golay codes with higher order Kerdock
codes, Mohammed Abouzaid and Nick Gurski, summer

1999.
Sponsored by Hewlett-Packard.

An examination
of codewords with optimal merit factor, Mike
Cammarano and Anthony Kirilusha, summer, 1998.

Sponsored by Hewlett-Packard.

Octary codewords with peak power 3.2^m, Katie Nieswand
and Kara Wagner, summer, 1998. Sponsored by

Hewlett-Packard.

Using the Quantum Computer to break and Elliptic Curve Cryptosystem, Jodie Eicher and Yaw Opoku,

summer,
1997. This won the Student Research Symposium Natural Science Award at the
University of Richmond

in spring,
1998. Sponsored by Hewlett-Packard.

Power control in
Golay cosets, Mike Cammarano and Meredith Walker, summer, 1997. Sponsored by

Hewlett-Packard.

Coding theory
over Galois Rings, Sarah Spence and Brian McKeever, Summer,
1995. This won a poster

presentation
at the annual Joint Math meetings of the American Mathematical Society and the
Mathematics

Association
of America in January, 1996.

**PH.D.
DISSERTATION DIRECTED:**

Constructing
partial difference sets using Galois Rings, John Polhill, University of
Virginia, 1999.

**GRANTS:**

National Science
Foundation, LURE, 2008-2011, $100,000

National** **Science Foundation, LURE, 2007-2011,
$1,500,000.

National
Security Agency Grant, salary, travel expenses, and support for undergraduate
research, January

2003-December
2005.

University of
Richmond Undergraduate Research Commmittee
Collaborative Grant, salary and travel for me

and two
students, summer 2002.

Hewlett-Packard Grant for Leave of Absence, academic year 2000-2001, paying
salary, moving expenses, cost

of living
expenses, and benefits.

Hewlett-Packard
Grant for undergraduate summer research institute, May 1997-August 2000, to
fund 4 students

full time
working on applied problems.

Hewlett-Packard sabbatical
Grant, August 1995-August 1996, funded move to England, half salary, other

expenses for
the academic year.

National Security Agency Young Investigator Grant, June 1995-June 1997,
summer salary and travel.

University of
Richmond Summer Research Grant, Summer 1994, salary.

National Security Agency Young Investigator Grant, June 1992-June 1994,
summer salary and travel.

Hewlett-Packard equipment grant (50 graphing calculators and supporting
equipment), summer 1993.

University of
Richmond Summer Research Grant, Summer 1989, salary.

**GRANTED PATENTS:**

K.K.
Smith, J. Jedwab, J.A. Davis, D. Banks and S.R. Wyatt, System for error
correction coding and decoding,

U.S.
Patent No. 7418644, 26 Aug 2008.

D. Banks, J. Davis, and J. Jedwab, Identifying uncorrectable codewords
in a Reed-Solomon decoder for

errors and erasures, US Patent No.
7278086, 2 October 2007.

J. Davis, K. Eldredge, J. Jedwab, G. Seroussi, and K. Smith, MRAM with controller, US Patent No. 7266732,

4
September 2007.

S.M.
Brandenberger, T. Munden,
J. Jedwab, J. Davis, and D. Banks, System and method for

configuring
a solid-state storage device with error correction coding, U.S. Patent No.
7,210,077, 24 Apr 2007.

J.
Jedwab, J.A. Davis and G. Seroussi, Method for error
correction decoding in a magnetoresistive

Solid-state storage device, U.S. Patent No. 7,149,949,
12 Dec 2006.

J.A.
Davis, J. Jedwab, S. Morley, K.G. Paterson, F.A. Perner,
K.K. Smith and S.R. Wyatt, Manufacturing

Test
for a fault tolerant magnetoresistive solid-state
storage device, U.S. Patent No. 7,149,948, 12 Dec 2006.

J.
Jedwab, J.A. Davis, K.G. Paterson and G. Seroussi,
Manufacturing test for a fault tolerant

magnetoresistive solid-state storage device, U.S. Patent No. 7107508,
12 Sep 2006.

J.A.
Davis, J. Jedwab, S. Morley, and K.G. Paterson, Magnetoresistive
solid-state storage device and

Data
storage methods therewith, U.S. Patent No. 7,107,507, 12 Sep 2006.

Error correction coding and decoding in a solid-state storage device, (with
J. Jedwab);

U.S. Patent No.
7,036,068, 25 April 2006.

Method for error correction decoding
in an MRAM device (historical erasures), (with J. Jedwab,

K.G. Paterson, and G. Seroussi); U.S. Patent No. 6,990,622, 24 Jan
2006.

Data storage method for
use in a magnetoresistive solid-state storage device,
(with J. Jedwab,

K.G. Paterson, G. Seroussi
and K. Smith);

Allocation of sparing resources in a magnetoresistive solid-state storage device, (with Jedwab);

U.S. Patent No. 6,973,604, 6 Dec
2005.

Methods and
apparatus for encoding and decoding data, European patent application No. 97 3

10252.8-2209
(with Jedwab); US patent 6,373,859, granted April 16, 2002.

Method and
apparatus for decoding data, (with Jedwab and Paterson); US patent 6,487,258,
granted

November 26,
2002.

System and
Method for Transmitting Data, US patent 6,119, 263, granted September 12, 2000.

**PENDING
PATENTS:**

Method and
apparatus for decoding COFDM-data, European patent application No. 98 3 10269.0
(with

Jedwab and
Paterson).

Complementary CRC polynomials, European patent application No. 97 3 02
946.5 (with Mowbray).

Error correction
coding and decoding in a solid-state storage device (with Jedwab,

McIntyre,Paterson,Perner,Seroussi, and Smith), US Patent
application

No.
2003/0023923.

Fault tolerant magnetoresistive solid-state storage device (with Eldredge,Jedwab,

McCarthy,Morley,Paterson,Perner,Smith, and Wyatt), US Patent
application

No.
2003/0023922.

**HONORS AND** **AWARDS:**

University of Richmond Outstanding Mentor Award, 2004.

University of
Richmond Distinguished Educator, 2000.

Roger Francis and Mary Saunders Richardson Chair of Mathematics,
1998-present.

President's
Fellowship for graduate study, University of Virginia, l983-86.

Phi Beta Kappa, l983.

Francis Shunks Downs Award for leadership, awarded by the President
of Lafayette College, 1983.

**PUBLICATIONS:**

Shared
Autocorrelation property of sequences, with C. Bodea, C. Copos, M. Der, and D.
O'Neal,

IEEE Transactions on Information Theory, Vol. 57 issue 6, 3805-3809, June 2011.

On the nonexistence of a projective (75,4,12,5) set in
PG(3,7), with A. Chan and J. Jedwab, Journal

Of Geometry, vol. 97 pp. 29-44, 2010.

Novel
Classes of Minimal Delay and Low PAPR Rate 1/2 Complex Orthogonal Designs, with S. Adams, N. Karst, M. K. Murugan,

B. Lee, IEEE Trans. on Inf. Th., Vol. 57 issue 4, 2254-2262, April 2011.

Difference set constructions of DRADs and
association schemes, with J. Polhill, J. Comb. Th. (A),

Vol. 117 Issue 5, 598-605, July 2010.

G-perfect Nonlinear Functions, with L. Poinsot,
Designs, Codes and Cryptography 46:1 January 2008

The design of the IEEE 802.12 coding scheme, with S.
Crouch and J. Jedwab, IEEE Transactions on

Communications, October 2007

Proof of the Barker
array conjecture, with J. Jedwab and K. Smith, Proceedings of the AMS,

Vol.
135, 2011-2018, 2007.

New amorphic
association schemes, with Q. Xiang, Finite Fields and their Applications, Vol.
12,

595-612,
2006.

Negative Latin
square type partial difference sets in nonelementary abelian 2-groups, with Q.
Xiang,

J. London
Math. Soc., Vol. 70 issue 1, 125-141, 2004.

Exponential
numbers of inequivalent difference sets in
Z_{2^{s+1}}^2, with D. Smeltzer, *Journal of*

*Combinatorial
Designs*,
Vol. 11 number 4, 249-259, 2003.

A Family of
partial difference sets with Denniston parameters in nonelementary abelian 2-groups,
with

Q.Xiang, *The European Journal of Combinatorics*, Vol. 00, 1-8, 2000.

Constructions of
low rank relative difference sets in 2-groups using Galois rings, with Q.Xiang, *Finite Fields*

*and their
Applications 6*, 130-145, 2000.

A unified
approach to difference sets with gcd(v,n)>1, with J. Jedwab, in T.Helleseth et al.,eds., NATO

Science
Series C, Difference Sets, Sequences and Their Correlation Properties, Vol.
542, Kluwer Academic

Publishers,
editor A. Pott and others, 85-112, Dordrecht.

Codes, correlations
and power control in OFDM, with J.Jedwab and K.Paterson, in T.Helleseth et al.,
eds.,

NATO Science
Series C, Difference Sets, Sequences and Their Correlation Properties, Vol.
542, Kluwer

Academic
Publishers, editor A. Pott and others, 113-132, Dordrecht.

A new family of
relative difference sets in 2-groups, with J. Jedwab, *Designs, Codes, and
Cryptography*

Memorial
Volume for Ed Assmus, Vol. 17, 305-312, 1999.

Peak-to-mean power control in OFDM, Golay
complementary sequences and Reed-Muller codes, with

J.Jedwab, *IEEE Transactions on Information Theory*, Vol. 45, 2397-2417, 1999.

Some recent
developments in difference sets, with J.Jedwab, in K. Quinn, B. Webb, F.
Holroyd and

C. Rowley,
eds., Pitman Research Notes in Mathematics,Combinatorial
Designs and their Applications,

Addison
Wesley Longman, 83-102, 1999.

A unifying
construction for difference sets, with J.Jedwab, *Journal
of Combinatorial Theory Series (A)*,

Vol. 80
No.1, 13-78, Oct. 1997.

Hadamard difference sets in nonabelian 2-groups, with J.Iiams, *Journal of
Algebra*, 199, 62-87, 1998.

Nested Hadamard difference sets, with J. Jedwab, *Journal** of Statistical Planning and
Inference*, vol. 62,

13-20, 1997.

Finding cyclic redundancy check polynomials for multilevel systems, with M.Mowbray and S.Crouch,

*IEEE
Transactions on Communications*, October, 1998, Vol. 46, Number 10, 1250-1253.

Peak-to-Mean power control and error correction for OFDM transmission using
Golay sequences and

Reed-Muller
codes, with J.Jedwab, *Electronics Letters*,
Vol. 33 No.4, 267-268, 13 February 1997.

New families of semi-regular relative difference sets, with J.Jedwab and M.Mowbray, *Designs,*

*Codes,
and Cryptography* 13, 131-146, 1998.

New semi-regular
divisible difference sets, *Discrete Mathematics*, 188, 99-109, 1998.

Construction of
relative difference sets in 2-groups using the simplex code, with S.Sehgal, *Designs,*

* Codes, and Cryptography*, 11, 1-11, 1997.

Recursive
construction for families of difference sets, with J. Jedwab, *Bulletin of
the ICA*, vol. 13,

p. 128,
1995, Research announcement.

Partial
difference sets in p-groups, *Archiv Mathematik*, 63, 103-110, 1994.

A Survey of Hadamard difference sets, with J. Jedwab, In K.T. Arasu
et.al., editors, *Groups, Difference*

*Sets, and
the Monster*, 145-156, de Gruyter, Berlin-New York, 1996.

Exponent bounds
for a family of abelian difference sets, with K.T.Arasu, J.Jedwab, S.L. Ma, and
R.

McFarland,
In K.T. Arasu et.al., editors, *Groups, Difference Sets, and the Monster*,
145-156, de Gruyter,

Berlin-New
York, 1996.

A nonexistence
result for abelian Menon
difference sets using perfect binary arrays, with K.T.Arasu

and J.Jedwab, *Combinatorica*,
15 (3), 311-317, 1995.

A construction
of difference sets in high exponent 2-groups using representation theory, with
K. Smith,

*Journal
of Algebraic Combinatorics*, Vol. 3, 137-151, 1994.

A note on new
semiregular divisible difference sets, with J. Jedwab, *Designs, Codes, and
Cryptography*, 3,

379-381,
1993.

Almost
difference sets and reversible divisible difference sets, *Archiv Mathematik*,
Vol. 59, 595-602, 1992.

Reply to
`Comment on ``Nonexistence of certain perfect binary arrays'' and
``Nonexistence of perfect binary

arrays,'' ',
with J.Jedwab, *Electronics Letters*, vol. 29 p.
1002, 1993.

A summary of Menon difference sets, with J. Jedwab, *Congressus
Numerantium*, vol. 93, 203-207, 1993.

Nonexistence of certain perfect binary arrays, with J.Jedwab, *Electronics
letters*, 29 No.1, 99-100, Jan.1992.

New
constructions on Menon difference sets, with K.T. Arasu,
J. Jedwab, and S.K. Sehgal, *Journal of*

*Combinatorial
Theory Series A*, Vol. 64 No.2, 329-336, Nov. 1993.

New constructions of divisible designs, *Discrete Mathematics*, Vol.
120, 261-268, 1993.

An exponent
bound for relative difference sets in p-groups, *Ars Combinatoria*, 34,
318-320, 1992.

Construction of
relative difference sets in p-groups, *Discrete Mathematics*, 103, 7-15,
1992.

A note on
products of relative difference sets, *Designs,
Codes, and Cryptography*, 1, 117-119, 1991.

A note on
intersection numbers of difference sets, with K.T. Arasu, D.Jungnickel,
and A.Pott, *European*

*Journal
of Combinatorics*, 11, 95-98,1990.

Some
nonexistence results on divisible difference sets, with K.T.Arasu,
D.Jungnickel, and A.Pott,

*Combinatorica*, 11, 1-8, 1991.

A generalization
of Kraemer's result on difference sets, *Journal of Combinatorial Theory
Series A*, March,

1992,
187-192.

A result on
Dillon's conjecture, *Journal of Combinatorial Theory Series A*, July 1991, 238-242.

A note on nonabelian (64,28,12) difference
sets, *Ars Combinatoria*, 32, 311-314, 1991.

Difference sets
in nonabelian 2-groups, *Coding Theory and Design
Theory*, Part II, IMA, v.21, 65-69,

Springer-Verlag.

Difference sets
in abelian 2-groups, *Journal of Combinatorial
Theory Series A*, July, 1991, 262-286.

**SUBMISSIONS
TO INTERNATIONAL NETWORKING STANDARDS:**

Low
complexity decoding for power controlled OFDM codes, with J. Jedwab and K.G.
Paterson,

ETSI BRAN
Working Group 3 (Hiperlan Type 2) Temporary Document 3hpl081a, March-April
1998.

Options for
variable rate coding in OFDM using binary, quaternary and octary modulation,
with J. Jedwab,

A. Jones, K.
Paterson, and T. Wilkinson, ETSI BRAN Working Group 3 (Hiperlan
Type 2) Temporary

Document 50,
Sept 1997.

**EXPOSITORY** **ARTICLES:**

The most exciting
thing ever in mathematics, __New Book of Popular Science__, Grolier, 1994.

How do we know
that anything is true?, __New Book of Popular Science__,
Grolier, 1993.

From schoolgirls
to CDs to Outer Space, __New Book of Popular Science__, Grolier, 1992.

**PRESENTATIONS:**

Linear algebra is the answer to everything: an industrial research
mathematics problem, Bloomsburg University colloquim, April 2005.

Relative difference sets and cohomology, a preliminary study, University of
Delaware discrete mathematics seminar, October 2004.

Bluffhead and other games, Cool Math seminar, University of
Richmond, September 2004.

The mathematics of 100 base vg, Central Michigan University Colloquium,
February 2004.

The mathematics of 100 base vg, Simon Fraser University Colloquium, January
2004.

The mathematics of 100 base vg, National meeting of the American
Mathematical Society,

Phoenix,
January 2004.

Negative Latin
Square type partial difference sets in non-elementary abelian
groups,

The British
Combinatorial Conference, July, 2003.

Finite Geometry
meets Galois Rings: the search for Denniston Partial
Difference Sets,

University
of Richmond Colloquium, March, 2002.

Inequivalent difference sets, University of Delaware Combinatorics Seminar, October,
2001.

Finite Geometry
meets Galois Rings: Construction of Denniston Partial
Difference

Sets, The
National University of Ireland, Maynooth, October,
2000.

The XTR
Cryptosystem, University of Bristol/Hewlett-Packard

Cryptography
Seminar, February, 2001.

Denniston partial difference sets, The National University of Singapore, June, 2000.

Denniston partial difference sets, The Ohio State-Denison conference, May, 2000.

The game of SETS and coding theory, Greater Richmond Council of Teachers of
Mathematics, March, 2000.

Relative
difference sets and Galois Rings, conference in Augsburg, Germany, August,
1999.

Relative
difference sets in groups whose order is not a prime power, seminar at the
University of Delaware,

March, 1999.

Golay complementary sequences
and Reed-Muller codes, conference in Bad Windsheim,
Germany,

August 6,
1998.

Unifying
construction for difference sets, Part II, conference in Bad Windsheim,
Germany, August 5, 1998.

Unifying construction for difference sets, Part I, conference in Bad
Windsheim, Germany, August 4, 1998.

Beauty and the mathematician, Lunchtime forum, University of Richmond,
December, 1997.

Construction of
relative difference sets in groups of non-prime power order, British
Combinatorial

Conference,
July, 1997.

The Kirkman schoolgirl problem to error
correcting codes, Randolph-Macon College colloquium,

November,
1996.

The Kirkman schoolgirl problem to error
correcting codes, University of Richmond colloquium,

September,
1996.

From the Kirkman schoolgirl problem to error
correcting codes: different views of difference sets,

The
University of Wales at Aberystwyth colloquium, May, 1996.

A unifying
construction of difference sets, The Basic Research in Mathematical Sciences
(BRIMS)

colloquium,
Bristol, England, April, 1996.

A unifying
construction of difference sets, Institut fur Mathematik der Universitat Augsburg, Augsburg,

Germany, March, 1996.

A recursive
construction of Relative difference sets, Royal Holloway University, London,
England,

February, 1996.

A recursive
construction of Relative difference sets, Bose Memorial Conference, Ft. Collins
CO, June 1995.

A new family of
difference sets, National Security Agency, May 1995.

K-matrices
revisited, Special Session on Codes and Designs, University of Richmond, Nov,
1994.

Partial
difference sets in p-groups, The Ohio State University/Denison University
conference, March 1994.

If at first you
don't succeed... a search for difference sets, Virginia Commonwealth University

colloquium, November, 1993.

Partial results on partial difference sets, the British Combinatorial
Conference, July, 1993.

Nonexistence
results on difference sets, the conference on Difference Sets at Ohio State
University, May,

1993 (one
hour talk).

A survey of Menon difference sets-- the nonabelian case, Southeastern
Combinatorics conference, Feb. 1993.

Difference sets
and perfect binary arrays, William and Mary colloquium, Jan. 1993.

If at first you
don't succeed... a search for difference sets, Central Michigan University
colloquium, May, 1992.

If at first you
don't succeed... a search for difference sets, talk to Ohio State combinatorics
seminar, May, 1992.

New constructions of divisible designs, the conference at Denison
University, May, 1992.

Almost
difference sets and divisible difference sets with multiplier -1, special
session on Designs and Codes,

Joint
meeting of the MAA and AMS, Baltimore, January 1992.

Error Correcting
Codes, Sigma Xi lecture, University of Richmond, December, 1990.

Relative
Difference Sets in p-Groups, Oberwolfach, April, 1990.

Coding Theory, Hampden-Sydney colloquium, October, l988.

Character Theory Applied to Difference Sets, Design Theory Workshop, IMA,
June, l988.

Difference Sets
in Abelian 2-Groups, Joint National Meeting of the
AMS-MAA, January, l988.

Difference Sets
in Abelian 2-Groups, Wright State University
colloquium, January, l988.

Difference Sets
in Abelian 2-Groups, National Security Agency
seminar, January, l987.

**OTHER
CONFERENCES AND COLLABORATIONS:**

Codes and
Designs, Oberwolfach, March, 1998.

Trip to Technion University, Haifa, Israel to
collaborate with mathematicians, March, 1998.

**CLASSES
TAUGHT:**

100 level: Introduction to Statistics, Statistics for the Social
Sciences, Calculus with precalculus.

200 level: Discrete math, Calculus 1, Calculus 2, Multivariate
Calculus, Linear Algebra.

300 level: Abstract Algebra 1, Abstract Algebra 2, Coding
Theory, Cryptography.

**SERVICE:**

Chair,
hiring committee, 2001-2002.

Chair, General
Education Committee, 2001-2002.

Chair of Math
and Computer Science department, 1997-2000, spring 2005.

Ethyl Committee, 1994-present.

Chair, hiring committee, 1994-95.

Curriculum committee, 1993-95.

Colloquium
chair, 1991-94.

Freshman advisor, 1991-95, 2001-Present.

Calculus committee, 1990-94.

**PROFESSIONAL** **AFFILIATIONS:**

Mathematical
Association of America

American Mathematical Society.

Fellow,
Institute of Combinatorics and its Applications