Numero
Veckobladet om forskning,
undervisning och
administration, m.m.
Nummer 38 · 18 november 2004 · Årgång 34      
NADA

ram

The Automatic Control group at S3, KTH welcomes you to the following defense of dissertation:

Design and analysis of feedback structures in
chemical plants and biochemical systems

Respondent: Henning Schmidt

December 7th, 13:00
kollegiesalen, Valhallavägen 79

Opponent: Prof Frank Allgöwer, Universität Stuttgart
Advisor: Doc Elling W Jacobsen

***

The Automatic Control group at S3, KTH welcomes you to the following defense of dissertation:

Experiment Design with Applications in
Identification for Control

Respondent: Henrik Jansson

December 3rd, 10:00
kollegiesalen, Valhallavägen 79

Opponent: Paul Van den Hof, Delft University of Technology
Advisor: Prof. Håkan Hjalmarsson

Abstract on next page

 

Welcome to Wireless Seminar
Electromagnetic fields and possible health effects - present and future research in Sweden

Prof Göran Grimvall, Royal Institute of Technology

Friday 19 November at 14.30
Wireless@KTH, Isafjordsgatan 30b, Kista

Read more: www.wireless.kth.se

Irina Radulescu


Information från systemgruppen om en planerad driftstörning

Lördagen den 27 november med start kl 10:00
kommer underhåll att utföras på Nadas AFS-servrar. Under det att arbetet pågår kommer många unix-datorer på Nada att vara ur funktion. Tjänster som e-post och WWW-servrar kommer också att påverkas.

***

Maintenance work on the AFS servers at Nada will be done on 27 November starting at 10:00 am. Most UNIX computers at Nada will be inoperable during this time. Other services, like E-mail and WWW servers, will also be affected.

Åsa Andersson

 


OMÖJLIGA FIGURER
seminarium på KTH den 25 november kl. 18-20 i Sing-Sing, Lindstedtsvägen 30.

“Figurer som ej kan existera, utan är en drift med perspektivet” står det i uppslagsboken. Men är det sant? Är Reutersvärds trappor och Eschers vattenfall omöjliga?

Birger Ljung, skulptör och professor i ekonomisk styrning på Industriell ekonomi, resonerar kring och visar (!) Reutersvärds omöjliga figur byggd i aluminium. Moderator är Roland Ljungberg, konstnär och prefekt för Instituinen för färg och form, Konstfack.

Filosofiska fragment är en öppen seminarieserie arrangerad av Institutionen för industriell ekonomi och organisation, KTH, som också bjuder på lättare förtäring

Alla seminarier i Filosofiska fragment är kostnadsfria.


ram
ram

The Automatic Control group at S3, KTH welcomes you to the following defense of dissertation:

Design and analysis of
feedback structures in chemical plants
and biochemical systems

Respondent: Henning Schmidt

December 7th, 13:00
kollegiesalen, Valhallavägen 79

Opponent: Prof Frank Allgöwer, Universität Stuttgart
Advisor: Doc Elling W Jacobsen

Abstract:
This thesis deals with modelling, analysis, and design of interactions between subsystems in chemical process plants and intracellular biochemical processes. In the first part, the focus is on the selection of decentralized feedback control structures for plants in the chemical process industry, with the aim of achieving a desired performance in the presence of interactions. The second part focuses on modelling and analysis of complex biochemical networks, with the aim of unravelling the impact of interactions between genes, proteins, and metabolites on cell functions.

Decentralized control is almost the de-facto standard for control of large-scale systems, and in particular for systems in the process industry. An important task in the design of a decentralized control system is the selection of the control configuration, the so-called input-output pairing, which effectively decides the subsystems. Previous research addressing this problem has primarily focused on the effect of interactions on stability. In this thesis, the problem of selecting control configurations that can deliver a desired control performance is addressed. It is shown that existing measures of interactions, such as the relative gain array (RGA), are poor for selecting configurations for performance due to their inherent assumption of perfect control. Furthermore, several model based tools for the selection of control configurations based on performance considerations are proposed.

Central functions in the cell are often linked to complex dynamic behaviors, such as sustained oscillations and multistability, in a biochemical reaction network. Determination of the specific interactions underlying such behaviors is important, for example, to determine sensitivity, robustness, and modelling requirements of given cell functions. A method for identifying the feedback connections and involved subsystems, within a biochemical network, that are the main sources of a complex dynamic behavior is proposed. The effectiveness of the method is illustrated on examples involving cell cycle control, circadian rhythms and glycolytic oscillations. Also, a method for identifying structured dynamic models of biochemical networks, based on experimental data, is proposed. The method is based on results from system identification theory, using time-series measurement data of expression profiles and concentrations of the involved biochemical components. Finally, in order to reduce the complexity of obtained network models, a method for decomposing large-scale networks into biologically meaningful subnetworks is proposed.

WELCOME!


The Automatic Control group at S3, KTH welcomes you to the following defense of dissertation:

Experiment Design with Applications in Identification for Control

Respondent: Henrik Jansson

December 3rd, 10:00
kollegiesalen, Valhallavägen 79

Opponent: Paul Van den Hof, Delft University of Technology, Advisor: Prof. Håkan Hjalmarsson

Abstract:
The main part of this thesis focuses on optimal experiment design for system identification within the prediction error framework.

A rather flexible framework for translating optimal experiment design into tractable convex programs is presented. The design variables are the spectral properties of the external excitations. The framework allows for any linear and finite-dimensional parametrization of the design spectrum or a partial expansion thereof. This includes both continuous and discrete spectra. Constraints on these spectra can be included in the design formulation, either in terms of power bounds or as frequency wise constraints. As quality constraints, general linear functions of the asymptotic covariance matrix of the estimated parameters can be included. Here, different types of
frequency-by-frequency constraints on the frequency function estimate are expected to be an important contribution to the area of identification and control.

For a certain class of linearly parameterized frequency functions it is possible to derive variance expressions that are exact for finite sample sizes. Based on these variance expressions it is shown that the optimization over the square of the Discrete Fourier Transform (DFT) coefficients of the input leads to convex optimization problems.

The optimal input design are compared to the use of standard identification input signals for two benchmark problems. The results show significant benefits of appropriate input designs.

Knowledge of the location of non-minimum phase zeros is very useful when designing controllers. Both analytical and numerical results on input design for accurate identification of non-minimum phase zeros are presented.

A method is presented for the computation of an upper bound on the maximum over the frequencies of a worst case quality measure, e.g. the worst case performance achieved by a controller in an ellipsoidal uncertainty region. This problem has until now been solved by using a frequency gridding and, here, this is avoided by using the Kalman-Yakubovich-Popov-lemma.

The last chapter studies experiment design from the perspective of controller tuning based on experimental data. Iterative Feedback Tuning (IFT) is an algorithm that utilizes sensitivity information from closed-loop experiments for controller tuning. This method is experimentally costly when multivariable systems are considered. Several methods are proposed to reduce the experimental time by approximating the gradient of the cost function. One of these methods uses the same technique of shifting the order of operators as is used in IFT for scalar systems. This method is further analyzed and sufficient conditions for local convergence are derived.

WELCOME!


ram
ram


 

Numero är institutionstidningen vid Nada - institutionen för numerisk analys och datalogi, KTH. Numero utkommer normalt på torsdags-förmiddagar under teminstid. Manus måste lämnas in före kl.12 på onsdagar.Manus, tips, förslag och andra bidrag till Numero kan lämnas på något av följande sätt:

Bidrag för artiklar och notiser bör i största möjliga mån vara färdigformulerade och korrekturlästa. Varje Numeronummer utkommer i två former:

Numeroredaktionen består av Maria Engström. Ansvarig utgivare är Ingrid Melinder. Numeros innehåll uttrycker inte institutionens officiella ståndpunkt annat än då detta anges.

 

ram
ram
Kalendarium
ram

ram

18 November

kl 15.00-16.30

“Entreprenörer från ett entreprenöriellt universitet”, Svante Littmarck och Sven Grahn. Bottenplanet i Sing Sing, INDEK

ram
ram

18 November

kl. 15.15

examensarbeten i datalogi: Building Consensus Trees using Gene Sequences - A Phylogenetic Approach. Steffansson, Pär. NTRUEncrypt and Lattice Attacks.
Rosenberg, Daniel, rum 4523

ram
ram

19 November

kl. 13.00


kl. 14.30

Doctoral Thesis, A Component Framework for Autonomous Mobile Robots, Anders Orebäck, kollegiesalen

Wireless Seminar Electromagnetic fields and possible health effects - present and future research in Sweden, Prof Göran Grimvall, Royal Institute of Technology
Wireless@KTH, Isafjordsgatan 30b, Kista

ram
ram

22 November

kl. 13:15



kl 18.30

TCS-Seminar, Difunctorial Semantics of Object Calculus: Towards Algebra of Objects, Johan Glimming, TCS, room 1537

populärvetenskapliga föreläsningar på AlbaNova. “Solvinden och kometer - laddade möten” professor Henrik Cederquist, Oskar Kleins auditorium

ram
ram

25 November

kl. 10.00

Seminarium om Språkverkstaden och studenternas språkkunskaper, Spelbomskan, Aula Magna

ram

25 November

kl. 18-20

seminarium OMÖJLIGA FIGURER, Birger Ljung, skulptör och professor i ekonomisk styrning på Industriell ekonomi i Sing-Sing, Lindstedtsvägen 30.

ram

26 November

kl 14.15,

Doctoral thesis, A new Kernel method for object recognition: Spin Glass-Markov random fields, Barbara Caputo, sal F2, Lindstedtsvägen 28

ram
ram

3 December

kl. 10.00

13.15

Defense of dissertation: Experiment Design with Applications in Identification for Control, Henrik Jansson, kollegiesalen, Valhallavägen 79

Doctoral Thesis, On Knowing Who Knows - An Alternative Approach to Knowledge Management, Kristina Groth, kollegiesalen

ram
ram

7 December

kl. 13:00

Defense of dissertation: Design and analysis of feedback structures in chemical plants and biochemical systems, Henning Schmidt, kollegiesalen, Valhallavägen 79

ram
ram

9 December

kl. 12.00 - 13.00


12.00 - 13.00, Seminar: HUMAINE: towards a sound foundation for emotion-oriented computing, Prof Roddy Cowie, DSV, floor 7, Forum-building, Kista

ram

16-17 December


Grid Computing and Beyond A symposium and a gala dinner in celebration of Professor S. Lennart Johnsson’s 60th birthday

 

ram
"Love doesn't make the world go round.  Love just makes the ride worthwhile."

Franklin P. Adams

ram