J. D.  Key
 
 
Jennifer D. Key
 BSc(Hons) (Rand) MPhil PhD (Lond) 
 Professor Emeritus of Mathematical Sciences,
School of Mathematical and Statistical Sciences, Clemson University.
Honorary Professor 
Aberystwyth University  or
IMPACS Aberystwyth,
 University of KwaZulu-Natal, 
University of the Western Cape.
Research Interests:
  Finite geometries, combinatorial designs, 
error-correcting codes, and groups. 
 See also 
Applicable Algebra Laboratory
Sample Publications:
- ``Designs and Their Codes," joint with  E. F. Assmus, Jr
(obituary), Cambridge 
University Press Tracts in Mathematics, No. 103, 1992.
(View 
Table of Contents 
and Preface. View errata files:
1992 (first printing) or
1993 (second printing).)
(CUP web site) 
- 
Designs and codes: an update, joint with E. F. Assmus, Jr,
Designs, Codes and Cryptography, 9 (1996), 7-27
View   
 or for the table of contents,
View 
-  Computational results for the
known biplanes of order 9, joint with V.D. Tonchev, in
Geometry, Combinatorial Designs, and Related Structures,
Editors: J.W.P. Hirschfeld and S. Magliveras and M.J. de Resmini,
Cambridge University Press, Cambridge,
London Math. Soc. Lecture Note Series 245 (1997),  113-122.
View 
-  Codes and finite geometries,
joint with E. F. Assmus, Jr,
INRIA Report, No. 2027, September 1993  (88 pages) 
(
View   
Table of Contents and Introduction) or 
read (ps)
or
read (pdf) chapter 
 joint with E. F. Assmus, Jr., on ``Polynomial 
Codes and Finite Geometries" in 
``Handbook of Coding Theory", Volume 2, Chapter 16, pages 1269--1343,
edited by  V.S. Pless and   W.C. Hufffman (Elsevier, 1998)
-  
 Small sets of even type and codewords, joint with M. J. de Resmini,
 J. Geom., 61 (1998), 83--104
View 
-  Bases of minimum-weight vectors for codes from designs,
 joint with S. Gao, 
Finite Fields and their Applications, 4 (1998) 1-15  
View 
-  Minimum weight and dimension formulas for some geometric codes,
 joint with  Neil J. Calkin  and Marialuisa J. de Resmini,
Des. Codes Cryptogr., 17 (1999), 105--120,
View   and 
to view some polynomial functions giving the dimension of the dual code
of the design of points and subspaces of dimension r over the field of
order q, as described in this paper, see 
polynomials and 
more.
-  Some error-correcting codes and their  applications, Chapter 19
of ``Applied Mathematical Modeling: A Multidisciplinary Approach",
D. R. Shier and K. T. Wallenius (Eds.), CRC Press, Boca Raton, FL, 1999
View 
- 
Geometric codes over fields of odd prime power order, 
joint with  K. L. Clark ,
Congr. Numer. 137 (1999), 177 - 186
View 
-  Rigidity theorems for a class of affine resolvable designs,
joint with K. Mackenzie Fleming,
J. Combin. Math. & Combin. Comput. 35 (2000), 147--160
View 
-  Ternary dual codes of the planes of order nine,
 joint with  M. J. de Resmini,
J. Statist. Plann. Inference, 95 (2001), 229 -- 236
View 
-  
Minimum-weight codewords as generators of generalized Reed-Muller codes,
joint with Peng Ding,
IEEE Trans. Inform. Theory, 46 (2000), 2152 --2158
View 
-  Some applications of Magma in designs and codes,
 J. Symbolic Comput., 31 (2001), 37-53
View 
- 
Subcodes of
projective generalized Reed-Muller codes spanned 
by  minimum-weight vectors, joint with Peng Ding,
 Des. Codes Cryptogr., 26 (2002), 197--211
View 
-  Codes, designs and groups from the Janko groups J1 and J2,
joint with J. Moori,
J. Combin. Math. & Combin. Comput. 40 (2002), 143--159
View 
-  Dual codes of translation planes,
joint with K. L. Clark and M. J. de Resmini,
European J. Combin., 23 (2002), 529--538
View 
-  Dual codes of projective planes of order 25,
joint with K. L. Clark, L. D. Hatfield and H. N. Ward,
Advanmath in Geometry,  3 (2003) Special Issue, 140--152
View 
-  Permutation decoding for the binary codes from triangular
graphs,
joint with J. Moori and B.G. Rodrigues,
European J. Combin., 25 (2004), 113--123
View 
-  Binary codes from graphs on triples,
joint with J. Moori and B.G. Rodrigues,
Discrete Math., 282 (2004), 171--182
View 
-  Binary codes from graphs on triples and permutation decoding,
joint with J. Moori and B.G. Rodrigues,
Ars Combin., 79 (2006), 11--19
View 
-  Partial permutation decoding for codes from finite planes,
 joint with T.P. McDonough and V.C. Mavron,
European J. Combin., 26 (2005), 665--682
View 
-  Partial permutation decoding for codes from 
Paley graphs,
joint with J. Limbupasiriporn,
Congr. Numer. 170 (2004), 143--155
View 
-  Information sets and partial permutation decoding for
  codes from finite geometries,
 joint with T.P. McDonough and V.C. Mavron,
Finite Fields Applic., 12 (2006), 232--247
View 
-  Recent developments in permutation decoding,
Notices of the South African Mathematical Society, April (2006)
View 
-  
Binary codes from rectangular lattice graphs and permutation decoding,
joint with P. Seneviratne,
 European J. Combin., 28 (2007), 121--126
View 
-  An upper bound for the minimum weight of the dual codes of
 desarguesian  planes,
 joint with T.P. McDonough and V.C. Mavron,
European J. Combin., 30 (2009), 220--229
View 
-  Minimum words of codes from affine planes, joint with D. Ghinelli and
M. J. de Resmini, J. Geom. 91 (2008), 43-51
View 
-  Graphs, designs and codes related to the n-cube, joint with W. Fish and
E. Mwambene, Discrete Math. 309 (2009), 3255-3269
View 
-  Binary codes from the line graph of the n-cube,
joint with W. Fish and E. Mwambene, 
J.  Symbolic Comput. 45 (2010) 800--812
View 
-  Codes associated with triangular graphs, and permutation decoding, joint
 with J. Moori and B. Rodrigues,
Int. J. Information and Coding Theory, Vol. 1, No. 3, (2010), 334-349
View 
-  Codes from lattice and related graphs, and permutation decoding,
joint
 with  B. Rodrigues,
Discrete Appl. Math., Vol. 158, (2010), 1807-1815
View 
-  Codes from  incidence matrices and line graphs of Paley graphs,
joint
 with  Dina Ghinelli,
Adv. Math. Commun., Vol. 5, (2011), 93--108
View 
-  Codes from  incidence matrices of graphs,
joint
 with  P. Dankelmann and B.G. Rodrigues,
Des. Codes Crytogr., Vol. 68, (2013), 393-393
View ,
 Online 
-  Hulls of codes from  incidence matrices of connected regular graphs,
joint
 with  Dina Ghinelli and   T. P. McDonough,
Des. Codes Crytogr., Vol. 70 (2014), 35-54
View ,
 Online 
-  Partial permutation decoding for simplex codes,
joint
 with  W. Fish and E. Mwambene,
Adv. Math. Commun., Vol. 6, (2012), 505-516
View ,
 Online 
-  A characterization of graphs by codes from their incidence matrices,
joint
 with  P. Dankelmann and B.G. Rodrigues,
Electron. J. Combinatorics 20(3) (2013), #P18
View
-  Codes associated with the odd graphs, joint with W. Fish and
E. Mwambene, Discrete Math. 315-316 (2014), 102-111
View 
- Codes from Hall planes of even order,
joint with
T.P. McDonough and V.C. Mavron,
J. Geom. 105 (2014), 33-41
View
-  Binary codes from reflexive graphs on 3-sets, joint with W. Fish and
E. Mwambene, 
Adv. Math. Commun. 9 (2015), 211-232
View 
-  Partial permutation decoding for MacDonald codes, joint 
with P. Seneviratne,
Appl. Algebra Engrg. Comm. Comput. 27 (2016), 399-412
View 
- Improved partial permutation decoding for Reed-Muller codes,
joint with
T.P. McDonough and V.C. Mavron,
Discrete Math. 340 (2017), 722-728
View
-   LCD codes from adjacency matrices of graphs,
joint with B. G. Rodrigues,
Appl. Algebra Engrg. Comm. Comput. 29 (3) (2018), 227-244
 DOI: 
10.1007/s00200-017-0339-6
View
-   Special LCD codes from Peisert and generalized Peisert graphs,
joint with B. G. Rodrigues,
Graphs Combin. 35 (2019), 633-652
 DOI:
https://doi.org/10.1007/s00373-019-02019-0
  View
-   Binary codes from $m$-ary $n$-cubes $Q^m_n$,
  joint with B. G. Rodrigues,
Adv. Math. Commun.
  
 DOI:
https://doi:10.3934/amc.2020079
  
    View
-  Special LCD codes from products of graphs,
  joint with W. Fish and E. Mwambene,
  Appl. Algebra Engrg. Comm. Comput.
  
 DOI:
  https://doi.org/10.1007/s00200-021-00517-4
  
    View
 
 
Some designs from my Magma files:
-  Projective planes of order 9:
Hughes ,
derived (Hall) ,
dual derived .
- 
Projective planes of order 25:
Hughes ;
 translation planes:
derived (Hall),
 S3,
 S4,
 S5,
 A1,
 A2,
 A3,
 A4,
 A5,
 A6,
 A7,
 A8,
 B1,
 B2,
 B3,
 B4,
 B5,
 B6,
 B7,
 B8.
- 
Biplanes on 56 points:
biplanes .
- 
Dimension of code of finite geometry design:
Magma functions .
- 
Some symmetric designs with parameters of finite geometry designs:
 rank and group ,
designs ,
extended designs ,
sample run .
- 
Affine resolvable 2-(27,9,4) designs of Lam and Tonchev:
 weight distribution for 68 dual designs ,
designs 2-9 ,
designs 10-19 ,
designs 20-29 ,
designs 30-39,
designs 40-49, 
designs 50-59 ,
designs 60-68 .
- 
Janko groups and designs:
codes  or 
J1  or
J2 . 
New (2007/8):
Codes from the Janko groups: 2008 (text) or
pdf . A 6-PD-set of size 404 for J2 on [100,36,16] binary code:
6-PD-set.
- 
PD-sets for some codes:
 [126,56,6]  or 
[126,70,5]  or
[126,78,5]  and
more  and
RMcodes 
and
basis set
- 
Tame search (Rome 2008)
 BBH1_16  
BBH2_17  
BBS4_21  
DBBH2_18  
DBBS4_22  
DDEMP_9  
DDSF_13  
DEMP_8  
DHALL_5  
DJOHN_20  
DJOWK_7  
DLMRH_11  
DMATH_15  
DSFP_12  
HALL_4  
JOHN_19  
JOWK_6  
LMRH_10  
MATH_14  
SEMI2_2  
SEMI4_3  
Hughes9.m  
Hall9.m  
DHall9.m
- Simplex codes (2011)
 simplex   and a run for n=6 at
simp6LOG  ;  31 matrimath for a 30-PD-set for S_8
sim8_31.m  ;
Field extension construction:
ext_field.m
- Peisert graph decoding
 P49.m 
and a run 
run49.txt
Update paper Rome .
(Paper given in Rome June 2001 Quaderni del Seminario:
link to Rome )
Fq7 (Toulouse May 2003)
UWA (Aberystwyth June 2003)
PPD (Gregynog May 2004)
CU04 (Clemson October 2004)
AMS05 (AMS special session, University of Delaware, April 2005)
In U.K.
PMB05 (Pietermaritzburg, 2005)
SAMS05 
Cork06 (Cork 2006)
AMS_SS06 
VA07 (Charlottesville, VA, 2007)
CU07
SAMS07 
Combinatorics2008 (Lake Garda, June 2008)
ALCOMA2010 (Thurnau, 2010)
IRSEE3_2011 (Irsee 2011)
3ICMCTA_2011 (Cardona Castle, September 2011)
ICM Satellite 2014 (ICM Satellite Conference on Algebraic Coding Theory, August 2014)
CIMPA AIMS 2015 (CIMPA Research School on Algebraic Representation Theory, 
July 2015)
>
  
 
 email: 
keyj@clemson.edu
email: 
keyj@clemson.edu
Home page: http://www.math.clemson.edu/~keyj