My research interests are in mathematical control and systems theory, with emphasis on infinite-dimensional and nonlinear systems. Recent research topics include:

- infinite-dimensional control systems;
- sampled-data feedback systems;
- nonlinear systems and input-to-state stability theory;
- discontinuous and hysteretic feedback systems;
- control of non-negative systems including applications to mathematical biology;
- applications of control and systems theory to numerical analysis.

- Adam D. Mawby, Integral control of infinite-dimensional linear systems subject
to input hysteresis (2000), PDF
- James J. Coughlan, Absolute stability results for infinite-dimensional
discrete-time systems with applications to sampled-data integral
control (2007), PDF
- Zhenqing Ke, Sampled-data control: stabilization, tracking and disturbance
rejection (2008), PDF
- Elvijs Sarkans, Absolute stability and input-to-state stability
of Lur'e systems (2014), PDF
- Adam R. Bill, Nonnegative feedback systems in population ecology
(2016), PDF
- Max Gilmore, Control-theoretic analysis of forced dynamics (since 2016).

- Dr. Uwe Stroinski (1995-1996; EU funded
*Human Capital and Mobility*project, jointly with S. Townley) - Dr. Thomas Fliegner (1998-2001; EPSRC Research Grant, jointly with E.P. Ryan)
- Dr. Ilya Shvartsman (2004-2006; EPSRC Research Grant, jointly with E.P. Ryan)
- Dr. Bayu Jayawardhana (2006-2007; EPSRC Research Grant, jointly with E.P. Ryan)

C. Guiver, H. Logemann & B. Rüffer, Small-gain stability theorems for positive Lur’e inclusions, submitted for publication, 2017. PDF

C. Guiver, H. Logemann & M.R. Opmeer, Transfer functions of infinite-dimensional
systems: positive realness and stabilization, to appear in
*Mathematics of Control, Signals, and Systems*, 2017.
PDF

D. Franco, C. Guiver, H. Logemann & J. Perán,
Semi-global persistence and stability for a class of forced discrete-time
population models, *Physica D*, **360** (2017), 46-61.
PDF

C. Guiver, H. Logemann & S. Townley, Low-gain integral control for multi-input,
multi-output linear systems with input nonlinearities,
*IEEE Trans. Automatic Control*, **62** (2017), 4776-4783.
PDF

D. Franco, H. Logemann, J. Perán & J. Segura,
Dynamics of the discrete Seno population model: combined effects of
harvest timing and intensity on population stability,
*Applied Mathematical Modelling*, **48** (2017),
885-898.
PDF

A. Bill, C. Guiver, H. Logemann & S. Townley, The converging-input
converging-state property for Lur'e systems,
*Mathematics of Control, Signals, and Systems*, **29**
(2017).
PDF

E. Sarkans & H. Logemann, Input-to-state stability of discrete-time
Lur'e systems, *SIAM J. Control and Optimization*, **54** (2016),
1739-1768.
PDF

A. Bill, C. Guiver, H. Logemann & S. Townley, Stability of non-negative
Lur'e systems, *SIAM J. Control and Optimization*, **54** (2016),
1176-1211.
PDF

E. Sarkans & H. Logemann, Stability of higher-order discrete-time Lur’e
systems, *Linear Algebra and its Applications*, **506** (2016),
183-211.
PDF

E. Sarkans & H. Logemann, Input-to-state stability of Lur'e systems,
*Mathematics of Control, Signals, and Systems*, **27** (2015),
439-465.
PDF

C. Guiver, H. Logemann, R. Rebarber, A. Bill, B. Tenhumberg, D. Hodgson
& S. Townley, Integral control for population management, *J. Mathematical Biology*, **70** (2015), 1015-1063.
PDF

D. Franco, H. Logemann & J. Perán, Global stability of an age-structured
population model, *Systems and Control Letters*, **65** (2014), 30-36.
PDF

H. Logemann, Stabilization of well-posed infinite-dimensional
systems by dynamic sampled-data feedback,
*SIAM J. Control and Optimization*, **51** (2013), 1203-1231.
PDF

B. Jayawardhana, H. Logemann & E.P. Ryan,
The circle criterion and input-to-state stability: new perspectives on
a classical result, *IEEE Control Systems Magazine*, **31**
(August 2011), 32-67.
PDF

A. Ilchmann, Z. Ke & H. Logemann, Indirect sampled-data control with sampling
period adaptation, *Int. J. Control*, **84** (2011), 424-431.
PDF

A. Ilchmann, H. Logemann & E.P Ryan, Tracking with prescribed transient
performance for hysteretic systems, *SIAM J. Control and Optimization*,
**48** (2010). 4731-4752.
PDF

H. Logemann & E.P. Ryan, Volterra functional differential equations:
existence, uniqueness and continuation of solutions, *American Mathematical
Monthly*, **117** (2010), 490-511. PDF

J. Coughlan & H. Logemann, Absolute stability and integral control for
infinite-dimensional discrete-time systems, *Nonlinear
Analysis*, **71** (2009), 4769-4789.
PDF

Z. Ke, H. Logemann & R. Rebarber, A sampled-data servomechanism for stable
well-posed systems, *IEEE Trans. Automatic Control*, **54** (2009),
1123-1128.
PDF

Z. Ke, H. Logemann & R. Rebarber, Approximate tracking and disturbance rejection
for stable infinite-dimensional systems using sampled-data low-gain control,
*SIAM J. Control and Optimization*, **48** (2009), 641-671.
PDF

B. Jayawardhana, H. Logemann & E.P. Ryan,
Input-to-state stability of differential inclusions with applications
to hysteretic and quantized feedback systems, *SIAM J. Control and
Optimization*, **48** (2009), 1031-1054.
PDF

Z. Ke, H. Logemann & S. Townley, Adaptive sampled-data integral control of stable
infinite-dimensional linear systems, *Systems and Control Letters*, **58**
(2009), 233-240.
PDF

B. Jayawardhana, H. Logemann & E.P. Ryan, Infinite-dimensional feedback systems:
the circle criterion and input-to-state stability, *Communications
in Information and Systems*, **8** (2008), 403-434.
PDF

B. Jayawardhana, H. Logemann & E.P. Ryan, PID control of second-order systems
with hysteresis, *Int. J. Control*, **81** (2008), 1331-1342.
PDF

H. Logemann, E.P. Ryan & I. Shvartsman, A class of differential-delay systems
with hysteresis: asymptotic behaviour of solutions, *Nonlinear Analysis*,
**69** (2008), 363-391.
PDF

H. Logemann, E.P. Ryan & I. Shvartsman, Integral control of infinite-dimensional
systems in the presence of hysteresis: an input-output approach, *ESAIM:
Control, Optimisation and Calculus of Variations*, **13** (2007), 458-483.
PDF

J. Coughlan, A.T. Hill & H. Logemann, The Z-transform and linear multistep
stability, *IMA Journal of Numerical Analysis*, **27** (2007), 45-73.
PDF

T. Fliegner, H. Logemann & E.P. Ryan, Absolute stability and integral control,
*Int. J. Control*, **79** (2006), 311-326.
PDF

H. Logemann, R. Rebarber & S. Townley, Generalized sampled-data stabilization of well-posed
linear infinite-dimensional systems, *SIAM J. Control and Optimization*, **44**
(2005), 1345-1369.
PDF

H. Logemann & E.P. Ryan, Asymptotic behaviour of nonlinear systems, *American Mathematical
Monthly*, **111** (2004), 864-889.
PDF

R.F. Curtain, H. Logemann & O. Staffans, Absolute stability results in infinite
dimensions, *Proceedings of the Royal Society: Mathematical, Physical and Engineering
Sciences*, **460** (2004), 2171-2196.
PDF

H. Logemann & A.D. Mawby, Extending hysteresis operators
to spaces of piecewise continuous functions, *J. Math. Analysis and
Applications*, **282** (2003), 107-127.
PDF

H. Logemann, R. Rebarber & S. Townley, Stability of infinite-dimensional sampled-data
systems, *Trans. American Mathematical Society*, **355** (2003), 3301-3328.
PDF

R.F. Curtain, H. Logemann & O. Staffans, Stability results of Popov-type for
infinite-dimensional systems with applications to integral control, *Proc.
London Mathematical Society*, **86** (2003), 779-816.
PDF

H. Logemann & E.P. Ryan, Non-autonomous systems: asymptotic behaviour and weak invariance
principles, *J. Differential Equations*, **189** (2003), 440-460.
PDF

H. Logemann & E.P. Ryan, Systems with hysteresis in the feedback loop: existence, regularity
and asymptotic behaviour of solutions, *ESAIM: Control, Optimisation and Calculus of
Variations*, **9** (2003), 169-196.
PDF

H. Logemann & S. Townley, Adaptive low-gain integral control of multivariable
well-posed linear systems, *SIAM J. Control and Optimization*, **41**
(2003), 1722-1732.
PDF

T. Fliegner, H. Logemann & E.P. Ryan, Low-gain integral control of continous-time
linear systems subject to input and output nonlinearities, *Automatica*,
**39** (2003), 455-462.
PDF

H. Logemann & A.D. Mawby, Discrete-time and sampled-data low-gain integral control
of infinite-dimensional linear systems in the presence of input hysteresis,
*SIAM J. Control and Optimization*, **41** (2002), 113-140.
PDF

T. Fliegner, H. Logemann & E.P. Ryan, Discrete-time low-gain control of linear systems
with input/output nonlinearities, *Int. J. of Robust and Nonlinear Control*, **11**
(2001), 1127-1143.
PDF

T. Fliegner, H. Logemann & E.P. Ryan, Adaptive low-gain integral control of linear systems
with input/output nonlinearities, *Systems and Control Letters*, **44** (2001),
1-12.
PDF

T. Fliegner, H. Logemann & E.P. Ryan, Low-gain integral control of well-posed linear
infinite-dimensional systems with input and output nonlinearities, *J. Math. Analysis
and Applications*, **261** (2001), 307-336.
PDF

W. Desch, H. Logemann, E.P. Ryan & E. Sontag, Meagre functions and asymptotic behaviour
of dynamical systems, *Nonlinear Analysis: Theory, Methods and Applications*,
**44** (2001), 1087-1109.
PDF

H. Logemann & E.P. Ryan, Time-varying and adaptive discrete-time low-gain control
of infinite-dimensional linear systems subject to input nonlinearities, *Mathematics
of Control, Signals, and Systems*, **13** (2000), 293-317.
PDF

H. Logemann & R.F. Curtain, Absolute stability results for infinite-dimensional
well-posed systems with applications to low-gain control, *ESAIM: Control,
Optimisation and Calculus of Variations*, **5** (2000), 395-424.
PDF

H. Logemann & E.P. Ryan, Time-varying and adaptive integral control of
infinite-dimensional regular linear systems with input nonlinearities,
*SIAM J. Control and Optimization* **38** (2000), 1120-1144.
PDF

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[My Homepage] [Department of Mathematical Sciences] [University of Bath]