
Biography 
Born in Brisbane, Australia,
March 5,1943.
Married, with three children, Benjamin James, Michael Stuart, Sofia
Elisabetta.
Resident in Italy from 1998.
Principal research interests: Theory of Continued Fractions, Universal Algebra, Topos Theory, Category Theory (2categories, Enriched categories, categories, bicategories, distributive and extensive), Computational Algebra, Theory of Automata and of Concurrency.
In 1971 founder, with R.H. Street, of "The Sydney Category Seminar", still active to 2005.
Has participated, presenting works and as program committee member, at numerous Australian, Italian and international conferences.
Member of the editorial committee of the journals:
Bulletin of the Australian Mathematical Society, 19791982,
Theory and Applications of Category Theory, from 1995.
Has received research grants from the Australian Research Council, in the years 1986–1999. Has participated in projects COFIN MIUR (ex MURST): "Tecniche formali per la specifica, l'analisi, la verifica, la sintesi e la trasformazione di sistemi software", “Tipi di Ordine Superiore e Concorrenza” (TOSCA), “Metamodelli Computazionali” (COMETA).
Has held the positions of:
Research Associate, per Prof. Saunders Mac Lane, University of Chicago, in the period JanuaryMay 1970.
Lecturer in Pure mathematics, University of Sydney, N.S.W. Australia, 19701976.
Senior Lecturer in Pure mathematics, University of Sydney, 19771989.
Associate Professor, University of Sydney, 19891999.
Honorary Associate Professor, University of Sydney, from 1999.
Contract Professor, University of Insubria, for the corse of Algebra Computazionale, Corso di Laurea in Matematica, A.A.199899, 19992000, 20002001.
Associate Professor, at the University of Insubria, scientific sector INF01, from 20012002.


Representative
publications 
K. R. Matthews and R.F.C.
Walters. Some properties of the continued fraction expansion of (m/n)e^(1/q).
Cambridge Philosophical Society, 67:6774, 1970. R. H. Street
and R.F.C. Walters. Comprehensive factorization of a functor. Bull.
Amer. Math. Soc., 79:936941, 1973.
R.H. Street and R.F.C. Walters. Yoneda structures on 2categories.
Journal of Algebra, 50:350379, 1978.
R.F.C. Walters. Sheaves on sites as Cauchycomplete categories.
Journal of Pure and Applied Algebra, 24:95102, 1982.
R. Betti, A. Carboni, R.H. Street, and R.F.C. Walters. Variation
through enrichment. Journal of Pure and Applied Algebra, 29:109127,
1983.
M.S. Johnson and R.F.C. Walters. The nerve of an ncategory. Cahiers
de Top. et G'eom. Diff., 257282, 1987.
A. Carboni and R.F.C. Walters. Cartesian bicategories I. Journal
of Pure and Applied Algebra, 49:1132, 1987.
R.F.C. Walters. Categories and Computer Science. Cambridge University
Press, 1992.
S. Carmody and R.F.C. Walters. Computing quotients of actions of
a free category. Springer Lecture Notes in Mathematics, 1488:6378,
1991.
M.S. Johnson and R.F.C. Walters. Algebra objects and algebra families
for finite limit theories. Journal of Pure and Applied Algebra,
83:283293, 1992.
W. Khalil and R.F.C. Walters. An imperative language based on distributive
categories II. Informatique Th'eorique et Applications, 27, 503522,
1993.
A. Carboni, S. Lack, and R.F.C. Walters. Introduction to extensive
and distributive categories. Journal of Pure and Applied Algebra,
84:145158, 1993.
G. M. Kelly, S. Lack, and R.F.C. Walters. Coinverters in categories
with structure. Applied Categorical Structures, 1:95102, 1993.
M. Leeming, R.F.C. Walters, A new application of the ToddCoxeter
procedure: computing left adjoints of algebraic functors. Proceedings
CANT 1992, Ed W
Bosma, A van der Poorten, Mathematics and its Applications, 325:5373,
1995
W. Khalil, E. Wagner, R.F.C. Walters, Fixpoint semantics for programs
in distributive categories. Fundamenta Informaticae, 22:187202,
1995
S. Bloom, N. Sabadini, R.F.C. Walters, Matrices, machines and behaviors.
Applied Categorical Structures, 4, 343360, 1996
N. Sabadini, S. Vigna, R.F.C. Walters, A note on recursive functions,
Mathematical Structures in Computer Science, 6:127139, 1996.
P. Katis, N. Sabadini, R.F.C. Walters, Bicategories of processes.
Journal of Pure and Appled Algebra, 115:141178, 1997.
P. Katis, N. Sabadini, R.F.C. Walters, Span(Graph): an algebra
of transition systems, Proceedings AMAST '97, SLNCS 1349, 322336,
1997
R. Rosebrugh, N. Sabadini, R.F.C. Walters, Minimal realization
in bicategories of automata, MSCS, 8:93116, 1998
P. Katis, N. Sabadini, R.F.C. Walters, A formalisation of the IWIM
Model. in: Proc. COORDINATION 2000,(Eds.) Porto A., Roman G.C.,
LNCS 1906:267283, Springer Verlag, 2000.
P. Katis, N. Sabadini, R.F.C. Walters, On the algebra of systems
with feedback & boundary, Rendiconti del Circolo Matematico
di Palermo Serie II, Suppl. 63
(2000), 123156
P. Katis, R.F.C. Walters, The compact closed bicategory of left
adjoints, Math. Proc. Camb. Phil. Soc., 130, 7787, 2001.
F. Gadducci, U. Montanari, P. Katis, N. Sabadini, R.F.C. Walters,
Comparing Cospanspans & Tiles via a Hoarestyle process calculus,
152171,
ENTCS 62, TOSCA Udine November 2001.
P. Katis, N. Sabadini, R.F.C. Walters, Feedback, trace and fixedpoint
semantics , Theoret. Informatics Appl. 36:181194 (2002)
N. Sabadini, R.F.C. Walters, Hierarchical automata and P systems,
CATS ’03, ENTCS 78, 115, 2003.
M.R. Bush, M. Leeming, R.F.C. Walters, Computing left Kan extensions,
35/2 107126, J. Symbolic Computation, 2003.
P. Katis, N. Sabadini, R.F.C. Walters, Compositional minimization
in Span(Graph): Some examples, Electronic Notes in Theoretical Computer
Science 104C, pp. 181197, 2004.
A. Cherubini, N. Sabadini, R.F.C. Walters, Timing in the CospanSpan
Model, Electronic Notes in Theoretical Computer Science 104C, pp.
8197, 2004.
R. Rosebrugh, N. Sabadini, R.F.C. Walters, Generic commutative
separable algebras and cospans of graphs, Theory and Applications
of Categories, 15, 264177, 2005.
