42,079 research outputs found
Coprime Factor Reduction of H-infinity Controllers
We consider the efficient solution of the coprime factorization based H infinity controller approximation problems by using frequency-weighted balancing related model reduction approaches. It is shown that for a class of frequency-weighted performance preserving coprime factor reduction as well as for a relative error coprime factor reduction method, the computation of the frequency-weighted controllability and observability grammians can be done by solving Lyapunov equations of the order of the controller. The new approach can be used in conjunction with accuracy enhancing square-root and balancing-free techniques developed for the balancing related coprime factors based model reduction
General computational approach for optimal fault detection
We propose a new computational approach to solve the optimal fault detection
problem in the most general setting. The proposed procedure is free of any technical assumptions
and is applicable to both proper and non-proper systems. This procedure forms the basis of
an integrated numerically reliable state-space algorithm, which relies on powerful descriptor
systems techniques to solve the underlying computational subproblems. The new algorithm has
been implemented into a Fault Detection Toolbox for Matlab
Computational issues in fault detection filter design
We discuss computational issues encountered in the design of residual generators for dynamic inversion based fault detection filters. The two main computational problems in determining a proper and stable residual generator are the computation of an appropriate leftinverse of the fault-system and the computation of coprime factorizations with proper and stable factors. We discuss numerically reliable approaches for both of these computations relying on matrix pencil approaches and recursive pole assignment techniques for descriptor systems. The proposed computational approach to design fault detection filters is completely general and can easily handle even unstable and/or improper systems
Analytic approximation of energy resolution in cascaded gaseous detectors
An approximate formula has been derived for gain fluctuations in cascaded
gaseous detectors such as GEM-s, based on the assumption that the charge
collection, avalanche formation and extraction steps are independent cascaded
processes. In order to test the approximation experimentally, a setup involving
a standard GEM layer has been constructed to measure the energy resolution for
5.9 keV gamma particles. The formula reasonably traces both the charge
collection as well as the extraction process dependence of the energy
resolution. Such analytic approximation for gain fluctuations can be applied to
multi-GEM detectors where it aids the interpretation of measurements as well as
simulations.Comment: 6 pages, 10 figures, submitted to Adv. in High Energy Phy
A Periodic Systems Toolbox for MATLAB
The recently developed Periodic Systems Toolbox for MATLAB is described. The basic approach to develop this toolbox was to exploit the powerful object manipulation features of MATLAB via flexible andfunctionally rich high level m-functions, while simultaneously enforcing highly efficient and numerically sound computations via the mex-function technology of MATLAB to solve critical numerical problems.The m-functions based user interfaces ensure user-friendliness in operating with the functions of this toolbox via an object oriented approach to handle periodic system descriptions. The mex-functions are based on Fortran implementations of recently developed structure exploiting and structure preserving numerical algorithms for periodic systems which completely avoid forming of lifted representations
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