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Yamalova, Diana
Publications (10 of 14) Show all publications
Yamalova, D. & Medvedev, A. (2019). Attractivity of the synchronous mode in hybrid observers for the impulsive Goodwin's oscillator subject to harmonic exogenous excitation. In: Proc. American Control Conference: ACC 2019. Paper presented at ACC 2019, July 10–12, Philadelphia, PA. American Automatic Control Council
Open this publication in new window or tab >>Attractivity of the synchronous mode in hybrid observers for the impulsive Goodwin's oscillator subject to harmonic exogenous excitation
2019 (English)In: Proc. American Control Conference: ACC 2019, American Automatic Control Council , 2019Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
American Automatic Control Council, 2019
National Category
Control Engineering
Identifiers
urn:nbn:se:uu:diva-382413 (URN)
Conference
ACC 2019, July 10–12, Philadelphia, PA
Note

to appear

Available from: 2019-04-25 Created: 2019-04-25 Last updated: 2019-05-07Bibliographically approved
Yamalova, D., Medvedev, A. & Zhusubaliyev, Z. (2019). Bifurcation analysis for non-local design of a hybrid observer for the impulsive Goodwin's oscillator.
Open this publication in new window or tab >>Bifurcation analysis for non-local design of a hybrid observer for the impulsive Goodwin's oscillator
2019 (English)In: Article in journal (Other academic) Submitted
National Category
Control Engineering
Identifiers
urn:nbn:se:uu:diva-382411 (URN)
Available from: 2019-04-25 Created: 2019-04-25 Last updated: 2019-05-07Bibliographically approved
Yamalova, D. & Medvedev, A. (2019). Hybrid observer with finite-memory output error correction for linear systems under intrinsic impulsive feedback. Automatica
Open this publication in new window or tab >>Hybrid observer with finite-memory output error correction for linear systems under intrinsic impulsive feedback
2019 (English)In: Automatica, ISSN 0005-1098, E-ISSN 1873-2836Article in journal (Other academic) Submitted
National Category
Control Engineering
Identifiers
urn:nbn:se:uu:diva-382412 (URN)
Available from: 2019-04-25 Created: 2019-04-25 Last updated: 2019-05-07Bibliographically approved
Yamalova, D. (2019). Hybrid observers for systems with intrinsic pulse-modulated feedback. (Doctoral dissertation). Uppsala: Acta Universitatis Upsaliensis
Open this publication in new window or tab >>Hybrid observers for systems with intrinsic pulse-modulated feedback
2019 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Dynamical processes resulting from the interaction of continuous and discrete dynamics are often encountered in living organisms. Time evolutions of such processes constitute continuous variables that are subject to instant changes at discrete points of time. Usually, these discrete events cannot be observed directly and have to be reconstructed from the accessible for measurement continuous variables.

Thus, the problem of hybrid state estimation from measurements of continuous outputs is important to and naturally arises in life sciences but, so far, scarcely covered in the existing literature.

This thesis deals with a special class of hybrid systems, where the continuous linear part is controlled by an intrinsic impulsive feedback that contributes discrete dynamics. The impacting pulsatile feedback signal is not available for measurement and, therefore, has to be reconstructed. To estimate all the elements of the hybrid state vector, an observation problem is considered.

The focus of the work is on a state observation problem for an analytically tractable example of a hybrid oscillator with rich nonlinear dynamics including, e.g., monostable and bistable high-periodic and quasiperiodic solutions as well as deterministic chaos. At the same time, the three-dimensional case of the considered hybrid oscillator constitutes a mathematical model of testosterone regulation in the male validated through system identification on human endocrine data. In a pulsatile endocrine regulation loop, one of the hormones (releasing hormone) is secreted in pulses from neurons in the hypothalamus of the brain. Thus a direct measurement of the concentration of this hormone in the human is not possible for ethical reasons and it has to be estimated in some manner from the available data, for instance by applying an observer.

It is desirable for an observer to guarantee asymptotic convergence of the state estimate to that of the observable plant from all feasible initial conditions at a highest possible rate. When the state estimation error is zero, the hybrid observer is in a synchronous mode characterized by the firings of the impulses in the observer feedback and those of the plant occurring simultaneously.

Therefore, the observer design problem can be formulated as synchronization of the plant states with those of the observer. This approach does not formally demand observability of the hybrid plant solution. Further, since the dynamics of the oscillator are highly nonlinear, the state estimation problem is considered with respect to particular solutions of the observed system, whose characteristics are assumed to be known, but not the initial conditions. The observer design problem for the impulsive Goodwin's oscillator consists of the selection of the observer structure and of assigning desired properties to a discrete map that captures the observer state transitions from one impulse firing to another through manipulating the degrees of freedom of the observer. 

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2019. p. 51
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1651-6214 ; 1812
Keywords
hybrid systems, impulsive systems, biomedical systems, Goodwin's oscillator, observers, time-delay
National Category
Control Engineering
Research subject
Electrical Engineering with specialization in Automatic Control
Identifiers
urn:nbn:se:uu:diva-382414 (URN)978-91-513-0665-0 (ISBN)
Public defence
2019-06-14, 2446, ITC, Lägerhyddsvägen 2, Uppsala, 09:15 (English)
Opponent
Supervisors
Available from: 2019-05-27 Created: 2019-04-25 Last updated: 2019-06-18
Yamalova, D. & Medvedev, A. (2018). Robustification of the synchronous mode in a hybrid observer for a continuous system under an intrinsic pulse-modulated feedback. In: Proc. 16th European Control Conference: . Paper presented at ECC 2018, June 12–15, Limassol, Cyprus (pp. 107-112). IEEE
Open this publication in new window or tab >>Robustification of the synchronous mode in a hybrid observer for a continuous system under an intrinsic pulse-modulated feedback
2018 (English)In: Proc. 16th European Control Conference, IEEE, 2018, p. 107-112Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
IEEE, 2018
National Category
Control Engineering
Identifiers
urn:nbn:se:uu:diva-354827 (URN)10.23919/ECC.2018.8550264 (DOI)000467725300018 ()978-3-9524-2698-2 (ISBN)
Conference
ECC 2018, June 12–15, Limassol, Cyprus
Available from: 2018-11-29 Created: 2018-06-22 Last updated: 2019-06-19Bibliographically approved
Yamalova, D. & Medvedev, A. (2017). Design of a hybrid observer for an oscillator with an intrinsic pulse-modulated feedback. In: Proc. American Control Conference: ACC 2017. Paper presented at ACC 2017, May 24–26, Seattle, WA (pp. 1175-1180). American Automatic Control Council
Open this publication in new window or tab >>Design of a hybrid observer for an oscillator with an intrinsic pulse-modulated feedback
2017 (English)In: Proc. American Control Conference: ACC 2017, American Automatic Control Council , 2017, p. 1175-1180Conference paper, Published paper (Refereed)
Place, publisher, year, edition, pages
American Automatic Control Council, 2017
National Category
Control Engineering
Identifiers
urn:nbn:se:uu:diva-316001 (URN)10.23919/ACC.2017.7963112 (DOI)000427033301037 ()978-1-5090-5992-8 (ISBN)
Conference
ACC 2017, May 24–26, Seattle, WA
Available from: 2017-07-03 Created: 2017-02-23 Last updated: 2018-08-02Bibliographically approved
Yamalova, D., Churilov, A. & Medvedev, A. (2017). Hybrid Observer for an Intrinsic Impulsive Feedback System. Paper presented at IFAC 2017, 20th IFAC World Congress, July 9–14, Toulouse, France. IFAC-PapersOnLine, 50(1), 4570-4575
Open this publication in new window or tab >>Hybrid Observer for an Intrinsic Impulsive Feedback System
2017 (English)In: IFAC-PapersOnLine, ISSN 1045-0823, E-ISSN 1797-318X, Vol. 50, no 1, p. 4570-4575Article in journal (Refereed) Published
Abstract [en]

This paper deals with continuous plants subject to intrinsic pulse-modulated feedback, thus exhibiting hybrid closed-loop dynamics. The system structure implements a hybrid oscillator and arises in living organisms, e.g. when episodically firing neurons control the production of hormones in endocrine glands. Hybrid observers reconstructing both the continuous and discrete states of the hybrid plant from only continuous measured outputs are considered. They excel over the existing solutions through the introduction of two co-ordinated feedbacks of the output estimation error: one correcting the continuous state estimates and another adjusting the discrete ones. Different types of the feedback operator to the discrete estimates are analyzed. The observer design problem is reduced to synchronization of the observer solution with that of the plant. The synchronous mode of the observer is rendered locally stable by the selection of the feedback gains. Numerical illustration of the design procedure and observer performance with respect to a pulse-modulated model of testosterone regulation is provided.

Keywords
Observers, hybrid systems, impulsive systems, periodic systems
National Category
Control Engineering
Identifiers
urn:nbn:se:uu:diva-342175 (URN)10.1016/j.ifacol.2017.08.733 (DOI)000423964800256 ()
Conference
IFAC 2017, 20th IFAC World Congress, July 9–14, Toulouse, France
Funder
Swedish Research Council, 2015-05256
Available from: 2017-10-18 Created: 2018-02-19 Last updated: 2018-08-17Bibliographically approved
Yamalova, D. & Medvedev, A. (2017). Hybrid observers for an impulsive Goodwin’s oscillator subject to continuous exogenous signals. In: 2017 IEEE 56Th Annual Conference on Decision and Control (Cdc): . Paper presented at CDC 2017, IEEE 56:th Annual Conference on Decision and Control, December 12–15,2017, Melbourne, Australia (pp. 2396-2401). Piscataway, NJ: IEEE
Open this publication in new window or tab >>Hybrid observers for an impulsive Goodwin’s oscillator subject to continuous exogenous signals
2017 (English)In: 2017 IEEE 56Th Annual Conference on Decision and Control (Cdc), Piscataway, NJ: IEEE, 2017, p. 2396-2401Conference paper, Published paper (Refereed)
Abstract [en]

This paper deals with the state estimation problemin an impulsive model of Goodwin’s oscillator forced by acontinuous exogenous signal. The continuous linear part of themodel is controlled by an intrinsic impulsive feedback thatcontributes discrete dynamics to the closed-loop system. Theimpacting pulsatile feedback signal is not available for mea-surement and, therefore, has to be reconstructed. To estimateall the elements of the hybrid state vector, an observationproblem is considered. Two hybrid observer structures areproposed and evaluated: one based on reconstructing both thestates of the Goodwin’s oscillator and those of the exogenoussystem and another assuming that the exogenous signal, or afunction of it, is known. The observer design is reduced to aproblem of synchronizing the impulsive sequence produced bythe observer with that of the plant. It utilizes a local approach ofassigning a guaranteed convergence rate to the local dynamicsof a synchronous mode through output error feedback. Thedynamics of the proposed observer schemes are analyzed bymeans of pointwise discrete (Poincar ́e) maps and illustrated bynumerical simulation for a case of bistability in the oscillator.

Place, publisher, year, edition, pages
Piscataway, NJ: IEEE, 2017
Series
Proceedings / IEEE Conference on Decision and Control, ISSN 0743-1546
National Category
Control Engineering
Identifiers
urn:nbn:se:uu:diva-342163 (URN)10.1109/CDC.2017.8264000 (DOI)000424696902052 ()978-1-5090-2873-3 (ISBN)
Conference
CDC 2017, IEEE 56:th Annual Conference on Decision and Control, December 12–15,2017, Melbourne, Australia
Funder
Swedish Research Council, 2015-05256
Available from: 2018-01-23 Created: 2018-02-19 Last updated: 2019-04-25Bibliographically approved
Yamalova, D. (2017). Hybrid observers for systems with intrinsic pulse-modulated feedback. (Licentiate dissertation). Uppsala University
Open this publication in new window or tab >>Hybrid observers for systems with intrinsic pulse-modulated feedback
2017 (English)Licentiate thesis, comprehensive summary (Other academic)
Abstract [en]

This licentiate thesis deals with a special class of hybrid systems, where the continuous linear part is controlled by an intrinsic impulsive feedback that contributes discrete dynamics. The impacting pulsatile feedback signal is not available for measurement and, therefore, has to be reconstructed. To estimate all the elements of the hybrid state vector, an observation problem is considered.

The motivation for the research performed in this thesis comes from mathematical modelling of pulsatile endocrine regulation, where one of the hormones (a releasing hormone) is secreted in pulses from neurons in the hypothalamus of the brain. Thus a direct measurement of the concentration of this hormone in the human is not possible for ethical reasons and has to be estimated.

Several hybrid observer structures are proposed and evaluated. The observer design is reduced to a problem of synchronizing the impulsive sequence produced by the observer with that of the plant. It utilizes a local approach of assigning, through the output error feedback in both the discrete and continuous parts of the plant model, a guaranteed convergence rate to the local dynamics of a synchronous mode. Performance of the proposed observer schemes is analyzed by means of pointwise discrete (Poincaré) maps.

The first two papers of the thesis address the effects of observer design degrees of freedom on the convergence of the hybrid state estimation error. A generalization of the proposed observation scheme to hybrid impulsive systems with a time delay in continuous part of the plant is investigated in Paper III and Paper IV.

Place, publisher, year, edition, pages
Uppsala University, 2017
Series
Information technology licentiate theses: Licentiate theses from the Department of Information Technology, ISSN 1404-5117 ; 2017-001
National Category
Control Engineering
Research subject
Electrical Engineering with specialization in Automatic Control
Identifiers
urn:nbn:se:uu:diva-316058 (URN)
Supervisors
Available from: 2017-02-10 Created: 2017-02-23 Last updated: 2017-02-23Bibliographically approved
Yamalova, D., Churilov, A. & Medvedev, A. (2015). Design degrees of freedom in a hybrid observer for a continuous plant under an intrinsic pulse-modulated feedback. In: : . Paper presented at MICNON 2015, June 24–26, Saint Petersburg, Russia (pp. 1080-1085).
Open this publication in new window or tab >>Design degrees of freedom in a hybrid observer for a continuous plant under an intrinsic pulse-modulated feedback
2015 (English)Conference paper, Published paper (Refereed)
Series
IFAC-PapersOnLine ; 48:11
National Category
Control Engineering
Identifiers
urn:nbn:se:uu:diva-315992 (URN)10.1016/j.ifacol.2015.09.337 (DOI)
Conference
MICNON 2015, June 24–26, Saint Petersburg, Russia
Available from: 2015-09-27 Created: 2017-02-23 Last updated: 2017-02-23Bibliographically approved
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