Browsing by Subject "Feedback control systems."

Now showing 1 - 7 of 7

Open Access
Algebraic theory of linear multivariable control systems
(1998) Çetin, Sevgi Babacan
The theory of linear multivariable systems stands out as tlie most developed and sophisticated among the topics of system theory. In the literature, many different solutions are presented to the linear midtivariable control problems using three main approaches : geometric approacli, fractional approach and polynomial model based approach. This thesis is a first draft for a textbook on linear multivariable control which contains a description of solutions to the most of the standard algebraic feedback control problems using simple linear algebra and a minimal amount of polynomial algebra. These problems are internal stabilization, disturbance decoupling by state feedback and measurement feedback, output stabilization, tracking with regulation in a scalar system, regulator problem with a single output channel and decentralized stabilization.
Open Access
Effects of feedback on financial forecasting
(1996) Dirimtekin, Serra
The objective of this study is to examine the effects o f feedback on financial forecasting. In particular, the effects o f simple outcome feedback and cahbration feedback as a type of perfonuance feedback on the accuracy of probabilistic forecasts of stock pi iccs and market indices in dichotomous format are analyzed. The study is conducted on subjects comprised of undergraduate and graduate students from the Faculty of Business Administration at Bilkent University. The results indicate that feedback, especially calibration feedback, has a considerable effect on the performance o f forecasters. ImpUcations of these findings for financial forecasting are discussed and directions for future research are given.
Open Access
High-gain sampled-data control of interconnected systems
(2002) Altunel, Haluk
Stabilization of interconnected systems using adaptive, decentralized, high-gain, sampled-data controllers is considered. Main applications of high-gain methodology to various systems under modeling uncertainties are reviewed. Then, sampled-data, high-gain and decentralized control techniques are combined to nd a solution to stabilization of interconnected systems, while satisfying the overall synchronization of the whole system. It is shown that overall system can be stabilized in continuous and discrete time domains by applying an adaptation mechanism for perturbations with unknown bounds.
Open Access
Linear quadratic control for harmonic signals
(2001) Köroğlu, Hakan
Open Access
Ripple-free deadbeat control of sampled-data systems
(1990) Mumcuoğlu, Erkan Ünal
In this thesis, we consider the ripple-free deadbeat control problem for linear, multivariable sampled-data systems represented by state-space models. Existing results concerning the deadbeat/ripple-free deadbeat regulation and tracking problems are based on controller configurations of either constant state-feedback or discrete dynamic output feedback. In the thesis, the problem is analyzed for two new sampled-data controllers, namely, generalized sampled-data hold functions and multirate-output controllers. Some necessary and sufficient solvability conditions for the problem are stated by theorems in time-domain and frequency domain in terms of the open-loop system parameters. Several special cases are also considered as corollaries.
Open Access
Stability analysis and controller design for the heat equation with time delayed feedback
(2010) Çalışkan, Sina Yamaç
In this thesis, the stability analysis for the system defined by the heat equation with time delayed feedback is performed. In the first part of the thesis, stability conditions in terms of LMI conditions which are obtained from the analysis in time domain, are explained. Necessary and sufficient conditions for stability are obtained using a frequency domain analysis. In the second part of the thesis, robust stability conditions are obtained for the system with parametric uncertainty. In the third part, an 퐻∞ controller design procedure is given for this type of plants described by the heat equation with time delayed feedback. Finally, the results are illustrated with simulations.
Open Access
Stability and dwell time analysis of switched time delay systems
(2007) Tapkan, Osman Siraceddin
In this thesis we deal with stability analysis of switched feedback system with time delays. We assume that, at any given time for each “candidate” system a controller is designed and a fixed feedback system is obtained until the next switching instant. We investigate the conservativeness of an LMI-based stability test for the time delay systems. This test is used for the dwell time analysis. After obtaining the limitations of this test, we find the exact bounds of allowable parameters appearing in the LMI-based test, in order to optimize the dwell time. For this purpose we consider simple first order systems and higher order systems separately. We also consider the LQR-based switched feedback controllers with time delays and investigate the effects of weighting matrices Q and R on the dwell time.