Universität Stuttgart

Permanent URI for this communityhttps://elib.uni-stuttgart.de/handle/11682/1

Browse

Filters

Settings

Institute: search.filters.UBSInstitut.Institut für Systemtheorie und RegelungstechnikAuthor: search.filters.author.Allgöwer, Frank

Search Results

Now showing 1 - 10 of 21
  • Thumbnail Image
    ItemOpen Access
    Identification of models of heterogeneous cell populations from population snapshot data
    (2011) Hasenauer, Jan; Waldherr, Steffen; Doszczak, Malgorzata; Radde, Nicole; Scheurich, Peter; Allgöwer, Frank
    Background: Most of the modeling performed in the area of systems biology aims at achieving a quantitative description of the intracellular pathways within a "typical cell". However, in many biologically important situations even clonal cell populations can show a heterogeneous response. These situations require study of cell-to-cell variability and the development of models for heterogeneous cell populations. Results: In this paper we consider cell populations in which the dynamics of every single cell is captured by a parameter dependent differential equation. Differences among cells are modeled by differences in parameters which are subject to a probability density. A novel Bayesian approach is presented to infer this probability density from population snapshot data, such as flow cytometric analysis, which do not provide single cell time series data. The presented approach can deal with sparse and noisy measurement data. Furthermore, it is appealing from an application point of view as in contrast to other methods the uncertainty of the resulting parameter distribution can directly be assessed. Conclusions: The proposed method is evaluated using artificial experimental data from a model of the tumor necrosis factor signaling network. We demonstrate that the methods are computationally efficient and yield good estimation result even for sparse data sets.
  • Thumbnail Image
    ItemOpen Access
    Multivariable controller design for an industrial distillation column
    (1992) Allgöwer, Frank; Raisch, Jörg
    In this paper, we report our experience with the design of linear multivariable controllers for a staged binary distillation column with 40 trays. Controller design methods include H∞-minimization, DNA-design, CL-design and H2minimization. Results obtained at the real plant are shown.
  • Thumbnail Image
    ItemOpen Access
    Moment dynamics of Zirconia particle formation for optimizing particle size distribution
    (2019) Halter, Wolfgang; Eisele, Rahel; Rothenstein, Dirk; Bill, Joachim; Allgöwer, Frank
  • Thumbnail Image
    ItemOpen Access
    Validation and analysis of linear distillation models for controller design
    (1993) Amrhein, Michael; Allgöwer, Frank; Marquardt, Wolfgang
    It is a nontrivial task to decide whether a model describes the main dynamic characteristics of a process and to determine which model is to be preferred for controller design. Techniques for examining lineal models for controller design are described in Section 2. One focus of this paper is on tools for analysing multivariable processes in the frequency domain, for example, condition number and dynamic relative gain array (RGA) analysis. The latter tool is extended by the phase information of the RGA. A novel evaluation tool involving the singular directions over frequency of the respective processes is introduced. In Section 3, a new linear low-order model is compared to five models from the literature using the analysis tools introduced in Section 2. The new model directly exploits wave propagation phenomena, and, therefore, will be called the wave model. Finally, Section 4 shows briefly result of the H∞-coutrolled column where the controller is designed on the basis of the wave model. Simulations with a detailed nonlinear distillation model show that very good control action can be achieved with this model. Moreover, the linear model allows to predict the nonlinear closed loop behavior quite accurately.
  • Thumbnail Image
    ItemOpen Access
    Schneller sehen durch Regelungstechnik - Moderne Bildgebung in der Nanotechnologie
    (2004) Rieber, Jochen M.; Allgöwer, Frank; Stemmer, Andreas
    Die Nanotechnologie, also die Wissenschaft von Untersuchungen und Manipulationen im Nanometermaßstab, wird als eine der Schlüsseltechnologien des 21. Jahrhunderts angesehen. Wichtige Komponenten dieses aktuellen Forschungszweiges sind das Rastertunnelmikroskop und das Rasterkraftmikroskop, die den Blick in die Nanowelt erlauben. Dieser Artikel gibt einen einführenden Einblick in die Bildgebung der Nanowelt und versucht, den Beitrag von Systemtheorie und Regelungstechnik für die Nanotechnologie anhand der Regelung von Rasterkraftmikroskopen allgemeinverständlich zu beschreiben.
  • Thumbnail Image
    ItemOpen Access
    Chemical process control: a german perspective
    (1992) Allgöwer, Frank
    This paper focuses on developments in controller design that we think can have a significant impact on the solution of practical process control problems, and try to summarize the discussion in Germany on this subject.
  • Thumbnail Image
    ItemOpen Access
    Nonlinear control of an industrial distillation column by exact linearization
    (1989) Allgöwer, Frank; Sax, Antonius; Gilles, Ernst Dieter
    -
  • Thumbnail Image
    ItemOpen Access
    Nichtlinearer Reglerentwurf auf der Grundlage exakter Linearisierungstechniken
    (1993) Allgöwer, Frank; Gilles, Ernst Dieter
    Dem nichtlinearen Reglerentwurf mittels exakter Linearisierung liegt eine Zweischritt-Philosophie zugrunde: zuerst wird die nichtlineare Regelstrecke durch eine nichtlineare Rückführung exakt in ein lineares System überführt. Das exakt linearisierte System kann im zweiten Schritt mit linearen Reglerentwurfsverfahren so geregelt werden, daß Stabilität und gutes Regelverhalten erreicht werden. In diesem Übersichtsbeitrag wird eine Einführung und ein Überblick über das Gebiet der exakten Linearisierung gegeben. Anhand von Beispielen werden die Vorteile und Grenzen der Verfahren diskutiert.
  • Thumbnail Image
    ItemOpen Access
    Chemical process control : present status and future needs ; the view from European industry
    (1991) Schuler, Hans; Allgöwer, Frank; Gilles, Ernst Dieter
    Not only in Europe, chemical process control is characterized by a broad invasion of distributed control systems into chemical plants. The information integration from process control up to business management is a great challenge of today which follows from the overall computerization of production. Most of the recent progress in process automation results from the application of computer science paradigms to control systems, and of advanced developments in field instrumentation. Despite these advances and the considerable progress made in process control theory, there is only limited acceptance and application of modern advanced process control methodologies in industrial practice. This paper is an attempt to summarize the European discussion on the reasons for these facts.
  • Thumbnail Image
    ItemOpen Access
    H∞-control of differential-algebraic-equation systems
    (1998) Rehm, Ansgar; Allgöwer, Frank
    In this paper H∞ control of high index and non-regular linear differential-algebraic-equation systems is addressed. Based on a generalization of the bounded real lemma (BRL) to index one systems, all linear output feedback controllers in standard, ie non-descriptor, state space form solving the H∞ control problem can be characterized via biaffine matrix inequalities (BMIs). In a second step a congruence transformation and a subsequent change of variables show that certain linear matrix inequalities (LMIs) necessarily must hold in order to admit a solution of the H∞ control problem. However, these conditions are not sufficient. Necessary and sufficient conditions for the existence of a controller solving the H∞ control problem are derived as BMIs of reduced order compared to the original characterization via the BRL. The approach is illustrated by a simple example.