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  • 151.
    Hendeby, Gustaf
    et al.
    Linköping University.
    Gustafsson, Fredrik
    Linköping University.
    Wahlström, Niklas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Gunnarsson, Svante
    Linköping University.
    A Platform for Teaching Sensor Fusion Using a Smartphone2017Inngår i: International journal of engineering education, ISSN 0949-149X, Vol. 33, nr 2B, s. 781-789Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A platform for sensor fusion consisting of a standard smartphone equipped with the specially developed Sensor Fusion appis presented. The platform enables real-time streaming of data over WiFi to a computer where signal processingalgorithms, e.g., the Kalman filter, can be developed and executed in a Matlab framework. The platform is an excellenttool for educational purposes and enables learning activities where methods based on advanced theory can be implementedand evaluated at low cost. The article describes the app and a laboratory exercise developed around these new technologicalpossibilities. The laboratory session is part of a course in sensor fusion, a signal processing continuation course focused onmultiple sensor signal applications, where the goal is to give the students hands on experience of the subject. This is done byestimating the orientation of the smartphone, which can be easily visualized and also compared to the built-in filters in thesmartphone. The filter can accept any combination of sensor data from accelerometers, gyroscopes, and magnetometers toexemplify their importance. This way different tunings and tricks of important methods are easily demonstrated andevaluated on-line. The presented framework facilitates this in a way previously impossible.

  • 152.
    Hidayat, Egi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    On Identification of Biological Systems2014Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    System identification finds nowadays application in various areas of biological research as a tool of empiric mathematical modeling and model individualization. A fundamental challenge of system identification in biology awaits in the form of response variability. Furthermore, biological systems tend to exhibit high degree of nonlinearity as well as significant time delays. This thesis covers system identification approaches developed for the applications within two particular biomedical fields: neuroscience and endocrinology.

    The first topic of the thesis is parameter estimation of the classical Elementary Motion Detector (EMD) model in insect vision. There are two important aspects to be taken care of in the identification approach, namely the nonlinear dynamics of the individual EMD and the spatially distributed structure of multiple detectors producing a measurable neural response. Hence, the suggested identification method is comprised of two consecutive stages addressing each of the above aspects. Furthermore, visual stimulus design for high spatial excitation order has been investigated.

    The second topic is parameter estimation of mathematical model for testosterone regulation in the human male. The main challenges of this application are in the unavailability of input signal measurements and the presence of an unknown pulsatile feedback in the system resulting in a highly nonlinear closed-loop dynamics. Semi-blind identification method has been developed based on a recently proposed pulse-modulated model of pulsatile endocrine regulation.

    The two system identification problems treated in the thesis bear some resemblance in the sense that both involve measured signals that can be seen as square-integrable functions of time. This property is handled by transforming the signals into the Laguerre domain, i.e. by equivalently representing the functions with their infinite Laguerre series.

    Delarbeid
    1. Laguerre domain identification of continuous linear time-delay systems from impulse response data
    Åpne denne publikasjonen i ny fane eller vindu >>Laguerre domain identification of continuous linear time-delay systems from impulse response data
    2012 (engelsk)Inngår i: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 48, nr 11, s. 2902-2907Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    An expression for the Laguerre spectrum of the impulse response of a linear continuous time-invariant system with input or output delay is derived. A discrete state-space description of the time-delay system in the Laguerre shift operator is obtained opening up for the use of conventional identification techniques. A method for Laguerre domain identification of continuous time-delay systems from impulse response data is then proposed. Linear time-invariant systems resulting from cascading finite-dimensional dynamics with pure time delays are considered. Subspace identification is utilized for estimation of finitedimensional dynamics. An application to blind identification of a mathematical model of an endocrine system with pulsatile regulation is also provided.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-183832 (URN)10.1016/j.automatica.2012.06.077 (DOI)000310717100020 ()
    Tilgjengelig fra: 2012-07-15 Laget: 2012-11-02 Sist oppdatert: 2017-12-07bibliografisk kontrollert
    2. Identification of a pulsatile endocrine model from hormone concentration data
    Åpne denne publikasjonen i ny fane eller vindu >>Identification of a pulsatile endocrine model from hormone concentration data
    2012 (engelsk)Inngår i: 2012 IEEE INTERNATIONAL CONFERENCE ON CONTROL APPLICATIONS (CCA), 2012, s. 356-363Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    This paper presents two approaches to estimate parameters of a mathematical model of a bipartite endocrine axis. Secretion of one of the involved hormones is stimulated by the concentration of another one, with the latter secreted in a pulsatile manner. The system output can be modeled as the response of a linear time-invariant system to a train of Dirac delta functions with unknown weights and fired at unknown instants. The hormone mechanism in question appears often in animal and human endocrine systems, e. g. in the regulation of testosterone in the human male. The model has been introduced elsewhere and makes use of pulse-modulated feedback for describing pulsatile endocrine regulation. The first identification approach is based on the mathematical machinery of constrained nonlinear least-squares minimization, while the second one is based on Laguerre domain identification of continuous time-delay systems. Both algorithm perform reasonably well on actual biological data yielding accurate fitting of luteinizing hormone concentration profiles.

    Serie
    IEEE International Conference on Control Applications, ISSN 1085-1992
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-206782 (URN)000320336200046 ()978-1-4673-4505-7 (ISBN)
    Konferanse
    IEEE International Conference on Control Applications (CCA) part of 6th IEEE Multi-Conference on Systems and Control (IEEE MSC), OCT 03-05, 2012, Dubrovnik, CROATIA
    Tilgjengelig fra: 2013-09-04 Laget: 2013-09-04 Sist oppdatert: 2014-02-10bibliografisk kontrollert
    3. Laguerre domain modeling of continuous time delay in the face of finite-dimensional perturbation
    Åpne denne publikasjonen i ny fane eller vindu >>Laguerre domain modeling of continuous time delay in the face of finite-dimensional perturbation
    2014 (engelsk)Artikkel i tidsskrift (Annet vitenskapelig) Submitted
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-215697 (URN)
    Tilgjengelig fra: 2014-01-15 Laget: 2014-01-15 Sist oppdatert: 2014-02-14
    4. Laguerre Domain Identification of the Elementary Motion Detector Model in Insect Vision
    Åpne denne publikasjonen i ny fane eller vindu >>Laguerre Domain Identification of the Elementary Motion Detector Model in Insect Vision
    2013 (engelsk)Inngår i: Adaptation and Learning in Control and Signal Processing, International Federation of Automatic Control , 2013, s. 623-628Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    A Laguerre domain approach to the identification of the so-called Elementary Motion Detector (EMD) that is hypothesized to constitute the basis of biological motion vision in nearly all animals is proposed. Despite the vast popularity of the EMD concept in both biology and biologically inspired computer vision, the problem of estimating the dynamics of the EMD from experimental data has been poorly addressed. The choice of the Laguerre domain for the representation of the input and the output of the EMD is motivated by the pulse-modulated character of the visual stimuli produced by the CRT displays that are often used in animal experiments. An analytical expression for the Laguerre spectrum of the EMD output given the Laguerre spectrum of the input is derived and a parameter estimation algorithm of the system dynamics is developed. The feasibility of the approach is illustrated by simulation using actual visual stimuli from fly electrophysiology.

    sted, utgiver, år, opplag, sider
    International Federation of Automatic Control, 2013
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-211727 (URN)10.3182/20130703-3-FR-4038.00070 (DOI)978-3-902823-37-3 (ISBN)
    Konferanse
    11th IFAC International Workshop on Adaptation and Learning in Control and Signal Processing
    Tilgjengelig fra: 2013-11-29 Laget: 2013-11-29 Sist oppdatert: 2014-02-10bibliografisk kontrollert
    5. Identification of the elementary motion detector model in fly motion vision from intracellularly recorded neural data
    Åpne denne publikasjonen i ny fane eller vindu >>Identification of the elementary motion detector model in fly motion vision from intracellularly recorded neural data
    2014 (engelsk)Artikkel i tidsskrift (Annet vitenskapelig) Submitted
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-215693 (URN)
    Tilgjengelig fra: 2014-01-15 Laget: 2014-01-15 Sist oppdatert: 2014-02-14bibliografisk kontrollert
    6. Spatial excitation properties of sinusoidal grating stimuli in the identification of a layer of motion detectors
    Åpne denne publikasjonen i ny fane eller vindu >>Spatial excitation properties of sinusoidal grating stimuli in the identification of a layer of motion detectors
    2014 (engelsk)Artikkel i tidsskrift (Annet vitenskapelig) Submitted
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-215691 (URN)
    Tilgjengelig fra: 2014-01-15 Laget: 2014-01-15 Sist oppdatert: 2014-02-14bibliografisk kontrollert
  • 153.
    Hidayat, Egi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    On identification of endocrine systems2012Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    System identification finds nowadays application in various areas of biomedical research as a tool of empiric mathematical modeling and model individualization. Hormone regulation is a classical example of biological feedback where control theories, in general, and system identification, in particular, are indispensable in unraveling the regulation mechanisms and explicating the complex dynamical phenomena arising in endocrine systems.

    The main function of endocrine feedback regulation is to maintain the hormone levels within a particular physiological range as well as to sustain an appropriate hormone secretion pattern. Therefore, a natural operating mode of a closed-loop endocrine system is a stable periodic cycle. This property significantly reduces the repertoire of readily available identification techniques, not least due to the fact that the regulation (input) signal is immeasurable in many practical cases.

    There are two approaches to blind identification of hormone dynamics presented in this thesis. The first one is based on constrained nonlinear least-squares method. Weighting functions play an important role in satisfying the biological conditions on the identified model. The second approach is derived from a novel time-delay system identification method in Laguerre domain. In the latter, the time delay appears due to a specific input signal model and is estimated along with the finite-dimensional dynamics of hormone kinetics.

  • 154.
    Hidayat, Egi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Identification of a pulsatile endocrine model from hormone concentration data2012Inngår i: 2012 IEEE INTERNATIONAL CONFERENCE ON CONTROL APPLICATIONS (CCA), 2012, s. 356-363Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents two approaches to estimate parameters of a mathematical model of a bipartite endocrine axis. Secretion of one of the involved hormones is stimulated by the concentration of another one, with the latter secreted in a pulsatile manner. The system output can be modeled as the response of a linear time-invariant system to a train of Dirac delta functions with unknown weights and fired at unknown instants. The hormone mechanism in question appears often in animal and human endocrine systems, e. g. in the regulation of testosterone in the human male. The model has been introduced elsewhere and makes use of pulse-modulated feedback for describing pulsatile endocrine regulation. The first identification approach is based on the mathematical machinery of constrained nonlinear least-squares minimization, while the second one is based on Laguerre domain identification of continuous time-delay systems. Both algorithm perform reasonably well on actual biological data yielding accurate fitting of luteinizing hormone concentration profiles.

  • 155.
    Hidayat, Egi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Laguerre domain identification of continuous linear time delay systems from impulse response data2011Inngår i: Proc. 18th IFAC World Congress, International Federation of Automatic Control , 2011Konferansepaper (Fagfellevurdert)
  • 156.
    Hidayat, Egi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Laguerre domain identification of continuous linear time-delay systems from impulse response data2012Inngår i: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 48, nr 11, s. 2902-2907Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An expression for the Laguerre spectrum of the impulse response of a linear continuous time-invariant system with input or output delay is derived. A discrete state-space description of the time-delay system in the Laguerre shift operator is obtained opening up for the use of conventional identification techniques. A method for Laguerre domain identification of continuous time-delay systems from impulse response data is then proposed. Linear time-invariant systems resulting from cascading finite-dimensional dynamics with pure time delays are considered. Subspace identification is utilized for estimation of finitedimensional dynamics. An application to blind identification of a mathematical model of an endocrine system with pulsatile regulation is also provided.

  • 157.
    Hidayat, Egi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Nordström, Karin
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Fysiologi.
    Identification of the Reichardt elementary motion detector model2015Inngår i: Signal and Image Analysis for Biomedical and Life Sciences, Springer, 2015, s. 83-105Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    The classical Hassenstein-Reichardt mathematical elementary motion detector (EMD) model is treated analytically. The EMD is stimulated with drifting sinusoidal gratings, which are often used in motion vision research, thus enabling direct comparison with neural responses from motion-sensitive neurones in the fly brain. When sinusoidal gratings are displayed on a cathode ray tube monitor, they are modulated by the refresh rate of the monitor. This generates a pulsatile signature of the visual stimulus, which is also seen in the neural response. Such pulsatile signals make a Laguerre domain identification method for estimating the parameters of a single EMD suitable, allowing estimation of both finite and infinite-dimensional dynamics. To model the response of motion-sensitive neurones with large receptive fields, a pool of spatially distributed EMDs is considered, with the weights of the contributing EMDs fitted to the neural data by a sparse estimation method. Such an EMD-array is more reliably estimated by stimulating with multiple sinusoidal gratings, since these provide higher spatial excitation than a single sinusoidal grating. Consequently, a way of designing the visual stimuli for a certain order of spatial resolution is suggested.

  • 158. Hjalmarsson, Håkan
    et al.
    Mårtensson, Jonas
    Rojas, Cristian R.
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    On the accuracy in errors-in-variables identification compared to prediction-error identification2011Inngår i: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 47, nr 12, s. 2704-2712Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Errors-in-variables estimation problems for single-input-single-output systems with Gaussian signals are considered in this contribution. It is shown that the Fisher information matrix is monotonically increasing as a function of the input noise variance when the noise spectrum at the input is known and the corresponding noise variance is estimated. Furthermore, it is shown that Whittle's formula for the Fisher information matrix can be represented as a Gramian and this is used to provide a geometric representation of the asymptotic covariance matrix for asymptotically efficient estimators. Finally, the asymptotic covariance of the parameter estimates for the system dynamics is compared for the two cases: (i) when the model includes white measurement noise on the input and the variance of the noise is estimated, and (ii) when the model includes only measurement noise on the output. In both cases, asymptotically efficient estimators are assumed. An explicit expression for the difference is derived when the underlying system is subject only to measurement noise on the output.

  • 159.
    Holmberg, Björn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Towards markerless analysis of human motion2005Licentiatavhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    The topic for this thesis is the analysis of human movement, or more specifically, markerless analysis of human movement from video material. By markerless analysis is meant that the full image material is used as input in contrast with traditional marker systems that only use the positions of marker centers. The basic idea is to use more of the information in the images to improve the analysis.

    Starting of with the aim of markerless analysis an application is designed that use, to the subject added texture to estimate the position of the knee joint center in real images. The approach show the plausibility of using subject texture for estimation purposes.

    Another issue that is addressed is how one can generate synthetic image data. Using basic tools of graphics programming a virtual environment used to synthesize data is created. This environment is also used to evaluate some different camera solutions.

    One method to make three dimensional reconstruction from multiple images of an object is tested using the synthetic data. The method is based on a "brute force" approach and does not show good performance in terms of computing speed. With appropriate representations of the three dimensional objects, mathematical methods might speed up the analysis.

  • 160.
    Hong, Mei
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Relations between bias-eliminating least squares, the Frisch scheme and extended compensated least squares methods for identifying errors-in-variables systems2009Inngår i: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 45, nr 1, s. 277-282Artikkel i tidsskrift (Fagfellevurdert)
  • 161.
    Hong, Mei
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Schoukens, Johan
    Pintelon, Rik
    Accuracy analysis of time-domain maximum likelihood method and sample maximum likelihood method for errors-in-variables identification2008Inngår i: Proc. 17th IFAC World Congress, International Federation of Automatic Control , 2008Konferansepaper (Fagfellevurdert)
  • 162.
    Hong, Mei
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Soverini, Umberto
    Diversi, Roberto
    Comparison of three Frisch methods for errors-in-variables identification2008Inngår i: Proc. 17th IFAC World Congress, International Federation of Automatic Control , 2008Konferansepaper (Fagfellevurdert)
  • 163.
    Hong, Mei
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Zheng, Wei Xing
    A simplified form of the bias-eliminating least squares method for errors-in-variables identification2007Inngår i: IEEE Transactions on Automatic Control, ISSN 0018-9286, E-ISSN 1558-2523, Vol. 52, nr 9, s. 1754-1756Artikkel i tidsskrift (Fagfellevurdert)
  • 164.
    Hong, Mei
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Zheng, Wei Xing
    Accuracy analysis of bias-eliminating least squares estimates for errors-in-variables systems2007Inngår i: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 43, nr 9, s. 1590-1596Artikkel i tidsskrift (Fagfellevurdert)
  • 165. Huang, Xiaolin
    et al.
    Shi, Lei
    Pelckmans, Kristiaan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Suykens, Johan A. K.
    Asymmetric nu-tube support vector regression2014Inngår i: Computational Statistics & Data Analysis, ISSN 0167-9473, E-ISSN 1872-7352, Vol. 77, s. 371-382Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Finding a tube of small width that covers a certain percentage of the training data samples is a robust way to estimate a location: the values of the data samples falling outside the tube have no direct influence on the estimate. The well-known nu-tube Support Vector Regression (nu-SVR) is an effective method for implementing this idea in the context of covariates. However, the nu-SVR considers only one possible location of this tube: it imposes that the amount of data samples above and below the tube are equal. The method is generalized such that those outliers can be divided asymmetrically over both regions. This extension gives an effective way to deal with skewed noise in regression problems. Numerical experiments illustrate the computational efficacy of this extension to the nu-SVR.

  • 166.
    Ilis, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Implementering av en PSS i Trängslets kraftstation2013Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [sv]

    The purpose of this master thesis is to implement and validate a Power System Stabilizer (PSS) to a generator at Trängslet hydropower station in Dalarna, Sweden. Problems with local rotor oscillations can occur at the hydropower station when power is transferred on a new power line (130 kV) from Northern to Southern part of Dalarna. To ensure good operation properties on this power line Fortum Generation AB and Fortum Distribution AB wants to activate a PSS on a generator.

    There have been investigations in which situations and what equipment that contributes to rotor oscillations. When this is known the PSS is tuned to damp these oscillations by choosing a good set of parameters. The most important parameters for good performance are to choose amount of gain and phase compensation. The chosen set of parameters are verified with a test in the power station to ensure that the task is completed.

    Test results shows that the magnitude of the first swing in rotor oscillation is almost the double than what PSS/E shows, but good correlation five seconds after initialization of the disturbance. The inherent dampening performance of the generator is much better in reality than in simulation. The chosen set of parameters contributes to rotor oscillation dampening in a magnitude approximately equal to simulation results in PSS/E, why the conclusion has been made that the implementation of the PSS is successful. There has also been made simulations with different power outputs and amount of generators synchronized whose results shows that damping is greatly increased with the chosen PSS.

  • 167. Irizar, Ion
    et al.
    Zambrano, Jesús
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Carlsson, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Morrás, Mikel
    Aymerich, Enrique
    Robust tuning of bending-points detection algorithms in batch-operated processes: Application to autothermal thermophilic aerobic digesters2015Inngår i: Environmental Modelling & Software, ISSN 1364-8152, E-ISSN 1873-6726, Vol. 71, s. 148-158Artikkel i tidsskrift (Fagfellevurdert)
  • 168. Irshad, Yasir
    et al.
    Mossberg, Magnus
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    System identification in a networked environment using second order statistical properties2013Inngår i: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 49, nr 2, s. 652-659Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    System identification for networked control is considered. Due to the time-delays in the network, it can be difficult to work with a discrete-time model and a continuous-time model is therefore chosen. A covariance function based method that relies on the second order statistical properties of the output signal, where it is assumed that the input signal samples are from a discrete-time white noise sequence, is proposed for estimating the parameters. The method is easy to use since the actual time instants when new input signal levels are applied at the actuator do not have to be known. An analysis of the networked system and the effects of the time-delays is made, and the results of the analysis motivate and support the chosen approach. Numerical studies indicate that the method is robust to randomly distributed time-delays, packet drop-outs, and additive measurement noise.

  • 169.
    Ivanic, Boris
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    AVR for a synchronous generator with a six-phase PM alternator and rotating excitation system2013Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    Automatic voltage regulation is necessary for all power producing synchronous generators to ensure that the produced power have a constant and stable voltage level and to sustain grid stability. The aim of this thesis is to design and build an automatic voltage regulator for a synchronous generator. A six-phase permanent magnet alternator will be used to excite the rotor with solid-state relay controlled rotating bridge rectifier. The field current is regulated by a closed loop control system that is based on a programmable logic controller, PLC.

    Programing of the PLC is executed in the developing environment CoDeSys, IEC 61131-3, which is the international standard for programing PLC applications. Simulations for predicting the system behavior is done with a web based in-browser tool, circuitlab.com.

    The results show a good performance of the regulator and the closed loop system although there is room for improvement of the solid-state controlled rectifier system. 

  • 170.
    Jansson, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Dynamic Smooth Pursuit Gain Estimation from Eye Tracking Data2011Inngår i: Proc. 50th Conference on Decision and Control, Piscataway, NJ: IEEE , 2011Konferansepaper (Fagfellevurdert)
  • 171.
    Jansson, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik.
    Identification Techniques for Mathematical Modeling of the Human Smooth Pursuit System2015Doktoravhandling, monografi (Annet vitenskapelig)
    Abstract [en]

    This thesis proposes nonlinear system identification techniques for the mathematical modeling of the human smooth pursuit system (SPS) with application to motor symptom quantification in Parkinson's disease (PD). The SPS refers to the complex neuromuscular system in humans that governs the smooth pursuit eye movements (SPEM). Insight into the SPS and its operation is of importance in a wide and steadily expanding array of application areas and research fields. The ultimate purpose of the work in this thesis is to attain a deeper understanding and quantification of the SPS dynamics and thus facilitate the continued development of novel commercial products and medical devices. The main contribution of this thesis is in the derivation and evaluation of several techniques for SPS characterization. While attempts to mathematically model the SPS have been made in the literature before, several key aspects of the problem have been previously overlooked.This work is the first one to devise dynamical models intended for extended-time experiments and also to consider systematic visual stimuli design in the context of SPS modeling. The result is a handful of parametric mathematical models outperforming current State-of-the-Art models in terms of prediction accuracy for rich input signals. As a complement to the parametric dynamical models, a non-parametric technique involving the construction of individual statistical models pertaining to specific gaze trajectories is suggested. Both the parametric and non-parametric models are demonstrated to successfully distinguish between individuals or groups of individuals based on eye movements.Furthermore, a novel approach to Wiener system identification using Volterra series is proposed and analyzed. It is exploited to confirm that the SPS in healthy individuals is indeed nonlinear, but that the nonlinearity of the system is significantly stronger in PD subjects. The nonlinearity in healthy individuals appears to be well-modeled by a static output function, whereas the nonlinear behavior introduced to the SPS by PD is dynamical.

  • 172.
    Jansson, Daniel
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Mathematical modeling of the human smooth pursuit system2014Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This licentiate thesis concerns mathematical modeling and identification of the the human smooth pursuit system (SPS) and the application of the models to motor symptom quantification in Parkinson's disease (PD).

    The SPS is a complex neuromuscular system governing smooth pursuit eye movements (SPEM), and the task is to keep a moving target in the visual field.

    Diagnosing and quantifying the disease is done by interview and clinical observation which requires hours of interaction between the patient and a qualified clinician. Acquiring a better understanding of the SPS cast in mathematical models may be a first step towards developing a technology that allows for fast and automatic PD staging.

    Lately, the increased performance and accessibility of eye tracking technologies have generated a great deal of interest in the commercial sector. This thesis presents an effort towards developing more sophisticated data analysis techniques in an attempt to extract previously hidden information from the eye tracking data and to open up for new more advanced applications.

    The SPS relates gaze direction to visual stimuli and may thus be viewed as a dynamical system with an input and an output signal. This thesis considers various parametric and non-parametric black- and grey-box models, both linear and nonlinear, to portray the SPS. The models are evaluated to characterize the SPS in different individuals and to look for discrepancies between the SPS function of healthy controls and Parkinson patients. It is shown that disease does indeed impair the system and that the effects are distinguishable from those of healthy aging.

    Delarbeid
    1. Mathematical modeling and grey-box identification of the human smooth pursuit mechanism
    Åpne denne publikasjonen i ny fane eller vindu >>Mathematical modeling and grey-box identification of the human smooth pursuit mechanism
    2010 (engelsk)Inngår i: Proc. International Conference on Control Applications: CCA 2010, Piscataway, NJ: IEEE , 2010, s. 1023-1028Konferansepaper, Publicerat paper (Fagfellevurdert)
    sted, utgiver, år, opplag, sider
    Piscataway, NJ: IEEE, 2010
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-136531 (URN)10.1109/CCA.2010.5611079 (DOI)000286943900123 ()978-1-4244-5362-7 (ISBN)
    Tilgjengelig fra: 2010-12-13 Laget: 2010-12-13 Sist oppdatert: 2018-10-01bibliografisk kontrollert
    2. Visual stimulus design in parameter estimation of the human smooth pursuit system from eye-tracking data
    Åpne denne publikasjonen i ny fane eller vindu >>Visual stimulus design in parameter estimation of the human smooth pursuit system from eye-tracking data
    2013 (engelsk)Inngår i: Proc. American Control Conference: ACC 2013, American Automatic Control Council , 2013, s. 887-892Konferansepaper, Publicerat paper (Fagfellevurdert)
    sted, utgiver, år, opplag, sider
    American Automatic Control Council, 2013
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-213879 (URN)10.1109/ACC.2013.6579948 (DOI)000327210201010 ()978-1-4799-0177-7 (ISBN)
    Konferanse
    ACC 2013, June 17-19, Washington, DC
    Tilgjengelig fra: 2013-06-19 Laget: 2014-01-05 Sist oppdatert: 2014-07-25bibliografisk kontrollert
    3. Non-parametric analysis of eye-tracking data by anomaly detection
    Åpne denne publikasjonen i ny fane eller vindu >>Non-parametric analysis of eye-tracking data by anomaly detection
    2013 (engelsk)Inngår i: Proc. 12th European Control Conference, IEEE , 2013, s. 632-637Konferansepaper, Publicerat paper (Fagfellevurdert)
    sted, utgiver, år, opplag, sider
    IEEE, 2013
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-224182 (URN)000332509701005 ()978-3-033-03962-9 (ISBN)
    Konferanse
    ECC 2013, July 17-19, Zürich, Switzerland
    Tilgjengelig fra: 2013-07-19 Laget: 2014-05-05 Sist oppdatert: 2014-06-12bibliografisk kontrollert
    4. Parametric and non-parametric stochastic anomaly detection in analysis of eye-tracking data
    Åpne denne publikasjonen i ny fane eller vindu >>Parametric and non-parametric stochastic anomaly detection in analysis of eye-tracking data
    2013 (engelsk)Inngår i: Proc. 52nd Conference on Decision and Control, Piscataway, NJ: IEEE , 2013, s. 2532-2537Konferansepaper, Publicerat paper (Fagfellevurdert)
    sted, utgiver, år, opplag, sider
    Piscataway, NJ: IEEE, 2013
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-226160 (URN)10.1109/CDC.2013.6760261 (DOI)978-1-4673-5714-2 (ISBN)
    Konferanse
    CDC 2013, December 10-13, Florence, Italy
    Tilgjengelig fra: 2014-03-07 Laget: 2014-06-12 Sist oppdatert: 2014-06-12bibliografisk kontrollert
    5. Volterra modeling of the smooth pursuit system with application to motor symptoms characterization in Parkinson's disease
    Åpne denne publikasjonen i ny fane eller vindu >>Volterra modeling of the smooth pursuit system with application to motor symptoms characterization in Parkinson's disease
    2014 (engelsk)Inngår i: 2014 European Control Conference (ECC), IEEE , 2014, s. 1856-1861Konferansepaper, Publicerat paper (Fagfellevurdert)
    Abstract [en]

    A new way of modeling the Smooth Pursuit System (SPS) in humans by means of Volterra series expansion is suggested and utilized together with Gaussian Mixture Models (GMMs) to successfully distinguish between healthy controls and Parkinson patients based on their eye movements. To obtain parsimonious Volterra models, orthonormal function expansion of the Volterra kernels in Laguerre functions with the coefficients estimated by SParse Iterative Covariance-based Estimation (SPICE) is used. A combination of these two techniques is shown to greatly reduce the number of model parameters without significant performance loss. In fact, the resulting models outperform the Wiener models of previous research despite the significantly lower number of model parameters. Furthermore, the results of this study indicate that the nonlinearity of the system is likely to be dynamical in nature, rather than static which was previously presumed. The difference between the SPS in healthy controls and Parkinson patients is shown to lie largely in the higher order dynamics of the system. Finally, without the model reduction provided by SPICE, the GMM estimation fails, rendering the model unable to separate healthy controls from Parkinson patients.

    sted, utgiver, år, opplag, sider
    IEEE, 2014
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-226162 (URN)10.1109/ECC.2014.6862207 (DOI)000349955702026 ()978-3-9524269-1-3 (ISBN)
    Konferanse
    13th European Control Conference (ECC), JUN 24-27, 2014, Strasbourg, France
    Tilgjengelig fra: 2014-06-27 Laget: 2014-06-12 Sist oppdatert: 2015-04-17bibliografisk kontrollert
  • 173.
    Jansson, Daniel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Parametric and non-parametric stochastic anomaly detection in analysis of eye-tracking data2013Inngår i: Proc. 52nd Conference on Decision and Control, Piscataway, NJ: IEEE , 2013, s. 2532-2537Konferansepaper (Fagfellevurdert)
  • 174.
    Jansson, Daniel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Visual stimulus design in parameter estimation of the human smooth pursuit system from eye-tracking data2013Inngår i: Proc. American Control Conference: ACC 2013, American Automatic Control Council , 2013, s. 887-892Konferansepaper (Fagfellevurdert)
  • 175.
    Jansson, Daniel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Volterra modeling of the smooth pursuit system with application to motor symptoms characterization in Parkinson's disease2014Inngår i: 2014 European Control Conference (ECC), IEEE , 2014, s. 1856-1861Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A new way of modeling the Smooth Pursuit System (SPS) in humans by means of Volterra series expansion is suggested and utilized together with Gaussian Mixture Models (GMMs) to successfully distinguish between healthy controls and Parkinson patients based on their eye movements. To obtain parsimonious Volterra models, orthonormal function expansion of the Volterra kernels in Laguerre functions with the coefficients estimated by SParse Iterative Covariance-based Estimation (SPICE) is used. A combination of these two techniques is shown to greatly reduce the number of model parameters without significant performance loss. In fact, the resulting models outperform the Wiener models of previous research despite the significantly lower number of model parameters. Furthermore, the results of this study indicate that the nonlinearity of the system is likely to be dynamical in nature, rather than static which was previously presumed. The difference between the SPS in healthy controls and Parkinson patients is shown to lie largely in the higher order dynamics of the system. Finally, without the model reduction provided by SPICE, the GMM estimation fails, rendering the model unable to separate healthy controls from Parkinson patients.

  • 176.
    Jansson, Daniel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Axelson, Hans
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Klinisk neurofysiologi.
    Nyholm, Dag
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Neurologi.
    Stochastic anomaly detection in eye-tracking data for quantification of motor symptoms in Parkinson's disease2015Inngår i: Signal and Image Analysis for Biomedical and Life Sciences, Springer, 2015, s. 63-82Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Two methods for distinguishing between healthy controls and patients diagnosed with Parkinson's disease by means of recorded smooth pursuit eye movements are presented and evaluated. Both methods are based on the principles of stochastic anomaly detection and make use of orthogonal series approximation for probability distribution estimation. The first method relies on the identification of a Wiener model of the smooth pursuit system and attempts to find statistically significant differences between the estimated parameters in healthy controls and patients with Parkinson's disease. The second method applies the same statistical method to distinguish between the gaze trajectories of healthy and Parkinson subjects tracking visual stimuli. Both methods show promising results, where healthy controls and patients with Parkinson's disease are effectively separated in terms of the considered metric. The results are preliminary because of the small number of participating test subjects, but they are indicative of the potential of the presented methods as diagnosing or staging tools for Parkinson's disease.

  • 177.
    Jansson, Daniel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Axelson, Hans
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Klinisk neurofysiologi.
    Nyholm, Dag
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Neurologi.
    Stochastic anomaly detection in eye-tracking data for quantification of motor symptoms in Parkinson's disease2013Inngår i: International Symposium on Computational Models for Life Sciences: CMLS 2013, Melville, NY: American Institute of Physics (AIP), 2013, s. 98-107Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Two methods for distinguishing between healthy controls and patients diagnosed with Parkinson's disease by means of recorded smooth pursuit eye movements are presented and evaluated. Both methods are based on the principles of stochastic anomaly detection and make use of orthogonal series approximation for probability distribution estimation. The first method relies on the identification of a Wiener-type model of the smooth pursuit system and attempts to find statistically significant differences between the estimated parameters in healthy controls and patientts with Parkinson's disease. The second method applies the same statistical method to distinguish between the gaze trajectories of healthy and Parkinson subjects attempting to track visual stimuli. Both methods show promising results, where healthy controls and patients with Parkinson's disease are effectively separated in terms of the considered metric. The results are preliminary because of the small number of participating test subjects, but they are indicative of the potential of the presented methods as diagnosing or staging tools for Parkinson's disease.

  • 178.
    Jansson, Daniel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Stoica, Peter
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Axelson, Hans W.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Klinisk neurofysiologi.
    Mathematical modeling and grey-box identification of the human smooth pursuit mechanism2010Inngår i: Proc. International Conference on Control Applications: CCA 2010, Piscataway, NJ: IEEE , 2010, s. 1023-1028Konferansepaper (Fagfellevurdert)
  • 179.
    Jansson, Daniel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Rosén, Olov
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Non-parametric analysis of eye-tracking data by anomaly detection2013Inngår i: Proc. 12th European Control Conference, IEEE , 2013, s. 632-637Konferansepaper (Fagfellevurdert)
  • 180.
    Jansson, Daniel
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Rosén, Olov
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Parametric and nonparametric analysis of eye-tracking data by anomaly detection2015Inngår i: IEEE Transactions on Control Systems Technology, ISSN 1063-6536, E-ISSN 1558-0865, Vol. 23, nr 4, s. 1578-1586Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An approach to smooth pursuit eye movement's analysis by means of stochastic anomaly detection is presented and applied to the problem of distinguishing between patients diagnosed with Parkinson's disease and normal controls. Both parametric Wiener model-based techniques and nonparametric modeling utilizing a description of the involved probability density functions in orthonormal bases are considered. The necessity of proper visual stimuli design for the accuracy of mathematical modeling is highlighted and a formal method for producing such stimuli is suggested. The efficacy of the approach is demonstrated on experimental data collected by means of a commercial video-based eye tracker.

  • 181. Johansson, Dongni
    et al.
    Ericsson, Anders
    Johansson, Anders
    Medvedev, Alexander
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Nyholm, Dag
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Neurologi.
    Ohlsson, Fredrik
    Senek, Marina
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Neurologi.
    Spira, Jack
    Thomas, Ilias
    Westin, Jerker
    Bergquist, Filip
    Individualization of levodopa treatment using a microtablet dispenser and ambulatory accelerometry2018Inngår i: CNS Neuroscience & Therapeutics, ISSN 1755-5930, E-ISSN 1755-5949, Vol. 24, nr 5, s. 439-447Artikkel i tidsskrift (Fagfellevurdert)
  • 182.
    Karlsson, E
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi. AUTOMATIC CONTROL.
    Stoica, P
    Söderström, T
    Computing the Cramer-Rao lower bound for noisy input output systems2000Inngår i: Signal Processing, Vol. 37, nr 4, s. 511-521Artikkel i tidsskrift (Fagfellevurdert)
  • 183. Katoulis, E. C.
    et al.
    Ebdon-Parry, M.
    Lanshammar, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Vileikyte, L.
    Kulkarni, J.
    Boulton, A. J.
    Gait abnormalities in diabetic neuropathy1997Inngår i: Diabetes Care, ISSN 0149-5992, E-ISSN 1935-5548, Vol. 20, nr 12, s. 1904-1907Artikkel i tidsskrift (Fagfellevurdert)
  • 184.
    Knorn, Steffi
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Middleton, Richard H.
    Univ Newcastle, Ctr Complex Dynam Syst & Control, Callaghan, NSW 2308, Australia..
    Asymptotic and exponential stability of nonlinear two-dimensional continuous-discrete Roesser models2016Inngår i: Systems & control letters (Print), ISSN 0167-6911, E-ISSN 1872-7956, Vol. 93, s. 35-42Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sufficient conditions guaranteeing Lyapunov stability, asymptotic stability and exponential stability of nonlinear two-dimensional continuous-discrete systems are proposed. Special attention is paid to neutrally stable systems such as some two-dimensional system descriptions of vehicle platoons, which may be stable or asymptotically stable but never exponentially stable. Our conditions for Lyapunov stability and asymptotic stability only require the corresponding two-dimensional Lyapunov function to have a negative semidefinite divergence. They are thus suitable for the analysis of non-exponential versions of 2D stability. Examples are given to illustrate the results.

  • 185. Kok, Manon
    et al.
    Khoshfetrat Pakazad, Sina
    Schön, Thomas B.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Hansson, Anders
    Hol, Jeroen D.
    A scalable and distributed solution to the inertial motion capture problem2016Inngår i: Proc. 19th International Conference on Information Fusion, IEEE, 2016, s. 1348-1355Konferansepaper (Fagfellevurdert)
  • 186. Kok, Manon
    et al.
    Schön, Thomas B.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Magnetometer calibration using inertial sensors2016Inngår i: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 16, nr 14, s. 5679-5689Artikkel i tidsskrift (Fagfellevurdert)
  • 187.
    Kreiberg, David
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Statistiska institutionen.
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Yang-Wallentin, Fan
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Statistiska institutionen.
    Errors-in-variables identification using covariance matching and structural equation modeling2013Inngår i: Proc. 52nd Conference on Decision and Control, Piscataway, NJ: IEEE , 2013, s. 5852-5857Konferansepaper (Fagfellevurdert)
  • 188.
    Kreiberg, David
    et al.
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Statistiska institutionen.
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Yang-Wallentin, Fan
    Uppsala universitet, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Samhällsvetenskapliga fakulteten, Statistiska institutionen.
    Errors-in-variables system identification using structural equation modeling2016Inngår i: Automatica, ISSN 0005-1098, E-ISSN 1873-2836, Vol. 66, s. 218-230Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Errors-in-variables (EIV) identification refers to the problem of consistently estimating linear dynamic systems whose output and input variables are affected by additive noise. Various solutions have been presented for identifying such systems. In this study, EIV identification using Structural Equation Modeling (SEM) is considered. Two schemes for how EIV Single-Input Single-Output (SISO) systems can be formulated as SEMs are presented. The proposed formulations allow for quick implementation using standard SEM software. By simulation examples, it is shown that compared to existing procedures, here represented by the covariance matching (CM) approach, SEM-based estimation provide parameter estimates of similar quality.

  • 189.
    Kung, Enoch
    et al.
    Hong Kong Univ Sci & Technol, Elect & Comp Engn, Kowloon, Hong Kong, Peoples R China..
    Dey, Subhrakanti
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Shi, Ling
    Hong Kong Univ Sci & Technol, Elect & Comp Engn, Kowloon, Hong Kong, Peoples R China..
    Optimal Stealthy Attack under KL Divergence and Countermeasure with Randomized Threshold2017Inngår i: IFAC-PapersOnLine, Elsevier, 2017, Vol. 50, nr 1, s. 9496-9501Konferansepaper (Fagfellevurdert)
    Abstract [en]

    In a cyber-physical system, there are potential sources of malicious attacks that can damage the estimation quality in an underlying network control system. The attacker aims to maximize these damages while the estimator attempts to minimize them. In this paper we define an attack's stealth based on the KL divergence and obtain an optimal attack. Furthermore, we suggest one method in which the estimator may limit the damage to the system while imposing on any attack a probability for it to be non-stealthy. (C) 2017, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved.

  • 190.
    Larsson, E K
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik. AUTOMATIC CONTROL.
    Söderström, T
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Continuous-time AR parameter estimation by using properties of sampled systems2002Inngår i: Proc. 15th IFAC World Congress, Barcelona, Spain, 2002Konferansepaper (Fagfellevurdert)
  • 191. Larsson, Erik K.
    et al.
    Mossberg, Magnus
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Estimation of Continuous-time Stochastic System Parameters2008Inngår i: Identification of Continuous-time Models from Sampled Data, London: Springer-Verlag , 2008, s. 31-66Kapittel i bok, del av antologi (Fagfellevurdert)
  • 192.
    Larsson, Erik K.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Mossberg, Magnus
    Söderström, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Identification of Continuous-Time ARX Models From Irregularly Sampled Data2007Inngår i: IEEE Transactions on Automatic Control, ISSN 0018-9286, E-ISSN 1558-2523, Vol. 52, nr 3, s. 417-427Artikkel i tidsskrift (Fagfellevurdert)
  • 193. Lau, Katrina
    et al.
    Goodwin, Graham C.
    Cea, Mauricio
    Wigren, Torbjörn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Linear and nonlinear decoupling for inner loop power control in 3G mobile communications2011Konferansepaper (Fagfellevurdert)
  • 194.
    Leong, Alex S
    et al.
    Department of Electical Engineering, Paderborn University, Tyskland.
    Quevedo, Daniel E
    Department of Electrical Engineering, Paderborn University, Tyskland.
    Tanaka, Takashi
    Royal Inst Technol, Sch Elect Engn, Dept Automat Control, Stockholm, Sweden.
    Dey, Subhrakanti
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Ahlén, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    Event-Based Transmission Scheduling and LQG Control Over a Packet Dropping Link2017Inngår i: 20th IFAC World Congress / [ed] Denis Dochain, Didier Henrion, Dimitri Peaucelle, Elsevier, 2017, s. 8945-8950Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper studies a joint transmission scheduling and controller design problem, which minimizes a linear combination of the control cost and expected energy usage of the sensor. Assuming that the sensor transmission decisions are event-based and determined using the random estimation error covariance information available to the controller, we show a separation in the design of the transmission scheduler and controller. The optimal controller is given as the solution to an LQG-type problem, while the optimal transmission policy is a threshold policy on the estimation error covariance at the controller.

  • 195.
    Lindholm, Karin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. IWR, Ruprecht-Karls-Universität Heidelberg, Germany.
    High Flying, Electrifying: Assessment and Extension of a Kite Model for Power Production2015Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    This thesis has its starting point in an existing computer model of an electricity generating kite, from Heidelberg University. The modelled kite has an area of 500 m2 and is tethered to a generator at sea. A control unit steers the kite in an optimised trajectory. The design and trajectory that maximise mean power output per loop had been found using the optimisation software MUSCOD-II.

    Firstly, the model is investigated in order to find possible adjustments to make it closer to reality. Then a method to take the economic aspect into account in the optimisation has been developed.

    The most important findings in the model survey concerned wind speed. The original model overrated the wind speed at high altitudes and it used a mean wind speed instead of including yearly variations. Adjustments are made and a new objective function aiming at maximising the yearly average power output per invested Euro is used.

    Furthermore, the revised model has a preset wind speed range within which the kite can operate, and a maximum power output of the generator (the nominal power) which is found through optimisation with respect of cost. Cable strength and other production limitations are included as well.

    Using cost estimations for relevant parts, the revised optimisation model results in a system with a tethering cable about half the original length, and a steadier power output over the loop. The yearly production sums up to 16.8 GWh, as compared to the original model which would have given 42.9 GWh yearly.

  • 196.
    Lindsten, Fredrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Bunch, Pete
    Särkkä, Simo
    Schön, Thomas B.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Godsill, Simon J.
    Rao–Blackwellized particle smoothers for conditionally linear Gaussian models2016Inngår i: IEEE Journal on Selected Topics in Signal Processing, ISSN 1932-4553, E-ISSN 1941-0484, Vol. 10, nr 2, s. 353-365Artikkel i tidsskrift (Fagfellevurdert)
  • 197. Lingvall, Andreas
    et al.
    Björkman, Mattias
    Wigren, Torbjörn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Avdelningen för systemteknik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Reglerteknik.
    Color vision based road estimation for automotive safety systems2000Inngår i: Proc. 7th, World Congress on Intelligent Transport Systems (ITS), 2000Konferansepaper (Fagfellevurdert)
  • 198.
    Lundvall, Alex
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Björklund, Jonas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Elektricitetslära.
    Optimering av reglering för pumpapplikation2019Independent thesis Basic level (professional degree), 10 poäng / 15 hpOppgave
  • 199. Lv, Mingsong
    et al.
    Guan, Nan
    Ma, Ye
    Ji, Dong
    Knippel, Erwin
    Liu, Xue
    Yi, Wang
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Institutionen för informationsteknologi, Datorteknik.
    Speed planning for solar-powered electric vehicles2016Inngår i: Proc. 17th International Conference on Future Energy Systems, New York: ACM Press, 2016, artikkel-id 6Konferansepaper (Fagfellevurdert)
  • 200. Ma, Mingxiao
    et al.
    Teixeira, André
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Signaler och System.
    van den Berg, Jan
    Palensky, Peter
    Voltage Control in Distributed Generation under Measurement Falsification Attacks2017Inngår i: IFAC-PapersOnLine, ISSN 2405-8963, Vol. 50, nr 1, s. 8379-8384Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Low-voltage distribution grids experience a rising penetration of inverter-based, distributed generation. In order to not only contribute to but also solve voltage problems, these inverters are increasingly asked to participate in intelligent grid controls. Communicating inverters implement distributed voltage droop controls. The impact of cyber-attacks to the stability of such distributed grid controls is poorly researched and therefore addressed in this article. We characterize the potential impact of several attack scenarios by employing the positivity and diagonal dominance properties. In particular, we discuss measurement falsification scenarios where the attacker corrupts voltage measurement data received by the voltage droop controllers. Analytical, control-theoretic methods for assessing the impact on system stability and voltage magnitude are presented and validated via simulation.

1234567 151 - 200 of 522
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