University
of Groningen
Home page of Ruth F. Curtain
Affiliation
Prof.dr.Ruth F. Curtain
University of Groningen
Department of Mathematics
P.O. Box 800
9700 AV Groningen
(The Netherlands)
IWI  building, room 321
Phone : +31 (0)50 3633985
Fax : +31 (0)50 3633800
Email : r.f.curtain@math.rug.nl
Biography and Research
Ruth F. Curtain was born in Melbourne,
Australia in 1941 and she
completed her early academic education (B.Sc. (Hons) 1962, Dip.Ed.
1963, M.A. Mathematics 1965) at the University of Melbourne. In 1966
she moved to the United States to study for a Ph.D. in Applied
Mathematics at Brown University, Providence, R.I., U.S.A. in 1969, and
subsequently as assistant Professor at Purdue University, (19701971).
The period 1971 to 1977 was spent at the University of Warwick, U.K.,
first, as a research fellow at the Control Centre and subsequently as
lecturer. She
joined the mathematics section in Groningen in 1977. Her research
interests lie
in the area of infinite dimensional systems theory and she has written
many research papers and three books, the latest with Hans Zwart: ``An
Introduction to Linear InfiniteDimensional Systems Theory'' (Springer
Verlag 1995). She has served as an associate editor for the
international journals Systems and Control Letters, Automatica,
Mathematics of
Control, Signals and Systems and for the Journal of Mathematical
Systems,
Estimation and Control and as an editor for Automatica. For
contributions to
the control theory of stochastic systems and infinitedimensional
systems she
was elected to the grade of Fellow in the IEEE. More about her current
research
interests can be found in Reciprocal
systems.
Farewell Lecture
On
retirement it is the custom that a professor deliver a farewell
address to colleagues, family and friends. The nature of the address
is a personal view of one's professional career at the university
and outside. On 12 September professor Curtain delivered her farewell
lecture with the title "An Australian looks back on 29 years at the
RUG". The lecture is a "sound and sight" presentation in Dutch and
accompanied by over 60 slides. Those interested can download a video
recording (Curtain.wmr) of the actual lecture in the main university
hall. Unfortunately, the colours of the slides are not visible, but
these can be seen in the pdf file "afscheid.pdf". English
speakers can follow the lecture using the English translation,
"Englishversion.pdf", interspersed with the slide titles and the pdf
file of the slides, "afscheid.pdf". Dutch speakers can do this in Dutch
using koppentext.pdf and "afscheid.df". The file "afscheidtext.tex" is
the plain unadulterated Dutch text.
Photo's of the day can be found at the link.......
 Curtain.wmv
 afscheid.pdf
 Englishversion.pdf
 koppentext.pdf
 afscheidtext.pdf

Administration
Recently the Faculty of Mathematics and the Natural
Sciences launched an
initiative to increase the number of women in the permanent scientific
staff. This was named the Rosalind Franklin Fellowship
programme and Professor Curtain coordinated this extremely successful
project that is documented in English
and in Dutch .
In the Netherlands the majority of Research Funding is coordinated
by the
Dutch Science Research Council. They are assisted in policy and funding
decisions by various subcommittees representing certain discipline
areas. In September 2003 she joined the committee responsible for
mathematics,
computing science and astronomy.
Publications
Papers Published in International Journals
 J.C. Oostveen and R.F. Curtain, Robustly stabilizing
controllers for dissipative infinitedimensional systems with colocated
actuators and sensors, Automatica, 36, 2000, 337348.
 J.C. Oostveen, R.F. Curtain and K. Ito, An approximation theory for strongly stablizing
solutions to the operator Riccati equation, SIAM J. Control
and Optimization, 38, 2000, 19091937.
 H.L. Logemann and R.F. Curtain, Absolute stability results for wellposed
infinitedimensional systems with applications to lowgain integral
control, ESIAM: Control, Optimization and Calculus of
variations, 5, 2000, 395424.
 R.F. Curtain and J.C. Oostveen, The Popov criterion
for strongly stable distributed parameter systems, International
Journal of Control, 74, 2001, 265280.
 A. Sasane and R.F. Curtain, Inertia
Theorems for Operator Lyapunov Inequalities, Systems and
Control Letters, 43, 2001, 127132.
 A. Sasane and R.F. Curtain,
Optimum Hankel Norm Approximation for the PritchardSalamon class of
infinitedimensional systems , J. Integral Equations and
Operator Theory, 39, 2001, 98126.
 R.F. Curtain and A. Sasane, Compactness and Nuclearity of the
Hankel operator and internal stability of infintedimensional linear
systems, Int. J. Control, 74, 12, 2001, 12601270.
 R.F. Curtain, Linear operator
inequalities for strongly stable weakly regular linear systems, Math.
Control Signals and Systems, 14, 2001, 299337.
 A. Sasane and R.F. Curtain, Hankel norm approximation for wellposed linear
systems, Systems and Control Letters, 48, 2003,
407414.
 R.F. Curtain, H.L. Logemann and O.J. Staffans, Stability results of Popovtype for wellposed
infinitedimensional systems with application to integral control
Proc. London Math.Soc., 86, 2003, 779816.
 R.F. Curtain, Riccati equations for
stable regular linear systems: the generic case, SIAM.
Journal of Control and Optim., 42, 2003, 16811702.
 R.F. Curtain, Regular linear systems
and their reciprocals: applications to Riccati equations, Systems
and Control Letters, 49, 2003, 8189.
 R.F. Curtain, M. Demetriou and K. Ito, Adaptive Compensators for Perturbed Positive Real
Infinite Dimensional Systems, Int. J, Applied Math. and
Computer Science, 13, No.4. pp. 441452, 2003.
 R.F. Curtain, H.L. Logemann and O.J. Staffans, Absolute stability in infinite
dimensions. Proc. Royal Soc. London, 460, 2004,
21712196.
 M.R. Opmeer and R.F. Curtain, New Riccati equations for wellposed linear
systems, Systems and Control Letters, 52, 339347, 2004.
 M.R. Opmeer and R.F. Curtain,
LGQbalancing for discretetime infinitedimensional systems. SIAM J.
Control and Optimization, 43 pp.11961221, 2004.
 M. Opmeer and R.F. Curtain,
The suboptimal Nehari problem for wellposed infinitedimensional
systems. SIAM J. Control and Optimization, 44
pp.9911018, 2005.
 M. Opmeer and R.F. Curtain,
Normalized coprime factorizations of wellposed infinitedimensional
systems, MCSS, to appear.
 O. Iftime and R.F Curtain and H.J. Zwart, A classification of the Algebraic Riccati
equations for infinitedimensional systems, Int. J. Control,
72 pp.505520, 2005.
 R.F. Curtain and G. Weiss,
Exponential stabilization of wellposed systems by colocated feedback,
SIAM, to appear.
 R.F. Curtain and G. Weiss,
Exponential stabilization of a Rayleigh beam using colocated control,
IEEE, to appear.
 R.F. Curtain, Robustly stabilizing
controllers with respect to leftcoprime factor perturbations for
infinitedimensional linear systems, Systems and Control Letters,
to appear.
 R.F. Curtain, A robust
LQGcontroller design for DPS, Int. J. Control, to appear.
Papers Published in Conference Proceedings
 R.F. Curtain and H.L. Logemann, A frequency domain
criterion for absolute stability of infinitedimensional systems with
applications to low gain control, Proc. MTNS 2000, (CDROM).
 A. Sasane and R.F. Curtain, Optimal Hankel Norm
Approximation for infinitedimensional systems, Proc. MTNS 2000,
(CDROM).
 R.F. Curtain and A. Sasane, Optimum Hankel Norm
Approximation for the Pritchard Salamon class of nonexponentially
stable infinitedimensional systems, Proc. 39 th IEEE Conference
on Decision and Control, Sydney, Australia, p. 45944599, 2000.
 J.C. Ooostveen and R.F. Curtain and K. Ito, An
approximation theory for strongly stabilizing solutions to the operator
LQ Riccati equation, Proc. 40 th IEEE Conference on Decision and
Control, Orlando, Florida, USA, 2001, p.123128.
 R.F. Curtain, Reciprocals of regular linear systems: a
survey. Proc. MTNS 2002, South Bend, Indiana, USA (CDROM or
www.nd.edu/ mtns).
 R.F. Curtain and A.J. Sasane, Explicit formulas for
Jspectral factors for wellposed linear systems. Proc. MTNS 2002,
South Bend, Indiana, USA (CDROM or www.nd.edu/ mtns).
 M. Opmeer and R.F. Curtain, LQGbalancing in infinite
dimensions Proc. MTNS 2002, South Bend, Indiana, USA (CDROM or
www.nd.edu/ mtns).
 R.F. Curtain, Recent results on reciprocals of wellposed
linear systems. Proc. MED'03, 11 th Mediterranean conference on Control
and Automation, Rhodes, Greece, IV1002, 2003. (CDROM).
 O.V. Iftime, R.F Curtain and H.J. Zwart, A
classification of the Algebraic Riccati equations for
infinitedimensional systems, Proceedings of the 42nd IEEE
Conference on Decision and Control, Hawaii, USA, pp. 18361841,
December 912, 2003 (CDROM).
 R.F. Curtain and M. Opmeer, The suboptimal Nehari
problem for stable infinitedimensional systems: bridging the gap.
Proc. 16 th Symposium on Mathematical Theory of Networks and Systems,
MTNS 2004. CDROM: ISBN 9056825178, Session WP5 (SYM6).
 R.F. Curtain and M. Opmeer, Normalized coprime
factorizations for state linear systems. Proceedings of the 5 th Asian
Control Conference, Melbourne, IEEE, 2004. (CDROM)
 R.F. Curtain, Robustly stabilizing controllers with
respect to leftcoprime factor perturbations for irrational transfer
functions, Proceedings of the 43 rd Conference on Decision and Control,
The Bahamas, IEEE, p.13581363, 2004. (CDROM)
 R.F. Curtain, Reciprocals of integrated nodes. Proceedings
of the 44 rd Conference on Decision and Control, Seville IEEE, 2005.
(CDROM)
Contributed chapters
 Ruth F. Curtain and Job.C. Oostveen, Normalized
Coprime Factorizations for Strongly Stabilizable Systems, in Fritz
Colonius, Uwe Helmke, Dieter Praetzel Wolters, Fabian Wirth (editors), Advances
in Mathematical Systems Theory: a volume in honor of Diederich
Hinrichsen, Birkhäuser, Boston, 2000, Chapter 13, p. 243254.
 Ruth F. Curtain, George Weiss and Martin Weiss, Stabilization of irrational transfer functions
with internal loop, p. 179208 in Systems, Approximation,
Singular integral operators and related topics, Int. workshop on
operator theory and applications, IWOTA 2000. Eds., Alexander A.
Borichev and Nikolai K. Nikolski, Vol. 129, 2001, in series Advances in
operator Theory and Applications, Birkhäuser.
 Ruth F. Curtain, On model reduction
for control design for distributed parameter systems, in Research
Directions in Distributer Parameter Systems, Ralph Smith and M.
Demetriou, (Editors), p.95 121,SIAM, Philadelphia, 2003.
Go back to:
Top of
this page
Systems and
Control Group
Department
of Mathematics and Computing Science
Staff