Search results for "Fuzzy control system"
showing 10 items of 96 documents
Nonlinear fuzzy control of a fed-batch reactor for penicillin production
2012
Abstract The process of penicillin production is characterized by nonlinearities and parameter uncertainties that make it difficult to control. In the paper the development and testing of a multivariable fuzzy control system that makes use of type-2 fuzzy sets for the control of pH and temperature are described. The performance of the type-2 fuzzy logic control system (T2FLCS) is compared by simulation with that of a type-1 fuzzy logic control system (T1FLCS) and that of a control system with traditional proportional-integral-derivative (PID) controllers proposed in the literature. The fuzzy controllers are optimized using an ANFIS algorithm. The best results are obtained with the T2FLCS pa…
Experimental Comparison of Type-1 and Type-2 Fuzzy Logic Controllers for the Control of Level and Temperature in a Vessel
2011
Abstract The objective of this experimental study is to compare the performance of type-1 and type-2 fuzzy logic controllers on a real system where the control of liquid level and temperature are considered. By the use of genetic algorithms it is possible to optimize the fuzzy sets of each fuzzy controller assuring high control performance. The experimental results show that a better control in terms of robustness can be achieved by type-2 fuzzy logic controllers.
A genetic algorithm for the design of a fuzzy controller for active queue management
2003
Active queue management (AQM) policies are those\ud policies of router queue management that allow for the detection of network congestion, the notification of such occurrences to the\ud hosts on the network borders, and the adoption of a suitable control\ud policy. This paper proposes the adoption of a fuzzy proportional\ud integral (FPI) controller as an active queue manager for Internet\ud routers. The analytical design of the proposed FPI controller is\ud carried out in analogy with a proportional integral (PI) controller,\ud which recently has been proposed for AQM. A genetic algorithm is\ud proposed for tuning of the FPI controller parameters with respect\ud to optimal disturbance rej…
Observer-based finite-time fuzzy H∞ control for discrete-time systems with stochastic jumps and time-delays
2014
This paper is concerned with the problem of observer-based finite-time H ∞ control for a family of discrete-time Markovian jump nonlinear systems with time-delays represented by Takagi-Sugeno (T-S) model. The main contribution of this paper is to design an observer-based finite-time H ∞ controller such that the resulting closed-loop system is stochastic finite-time bounded and satisfies a prescribed H ∞ disturbance attenuation level over the given finite-time interval. Sufficient criteria on stochastic finite-time H ∞ stabilization via observer-based fuzzy state feedback are presented for the solvability of the problem, which can be tackled by a feasibility problem in terms of linear matrix…
Fuzzy filter design for discrete-time delayed systems with distributed probabilistic sensor faults
2013
In this paper, the problem of distributed fuzzy filter design has been solved for T-S fuzzy systems with time-varying delays and multiple probabilistic packet losses. Our attention is paid to designing the distributed fuzzy filters to guarantee the filtering error dynamic system to be mean-square asymptotically stable with an average ℋ∞ performance. Sufficient conditions for the obtained filtering error dynamic system are proposed by applying a comparison model and the scaled small gain theorem. Based on the measurements and estimates of the system states for each sensor and its neighbors, the solution of the parameters of the distributed fuzzy filters is characterized in terms of the feasi…
Applying Cathegorical Metrics on Fuzzy Systems
2007
This work analyzes the categorical metrics usage on a very specific subset of Intelligent Systems: Fuzzy Systems. Several characteristics for such systems must be carefully evaluated when metrics and indicators are defined, in order to consider the fuzzy essence as part of the evaluation result. A set of metrics and indicators are defined and applied to the classical inverted pendulum problem. The paper does not intend to provide an exhaustive analysis of the quality evaluation on soft computing problem. It just presents a way to start the study of quality measure in that area.
D-stability for discrete-time t-s fuzzy descriptor systems with multiple delays
2014
In this work, the D-stability problem is considered for a class of discrete-time Takagi-Sugeno (T-S) fuzzy descriptor systems with multiple state delays. In terms of linear matrix inequality, sufficient conditions are proposed to ensure that all poles of the descriptor T-S fuzzy system are located within a disk contained in the unit circle. Moreover, a sufficient condition is presented such that the singular system is regular, causal and D-stable in spite of multiple state delays. Finally, an example is given to show the effectiveness and advantages of the proposed techniques Refereed/Peer-reviewed
How can we apply the models of the quality of life and the quality of life management in an economy based on knowledge?
2017
The scientific substantiations of quality have been applied to models that pertain to mathematical statistics, the probability theory, the information theory, fuzzy systems, graphic methods, time series, and algebraic and numerical methods. To these, this article aims to present a new method of applying mathematical modelling in an economy based on knowledge, by using the concept of the definite integral, the composite function, and mathematical optimisation. The research methods used in the realisation of this article are bibliographic research, creation of new models, and problem-solving. Mathematical modelling, the simulation of the quality of life, etc. are methods and techniques of bot…
Fuzzy Integral Imaging Camera Calibration for Real Scale 3D Reconstructions
2014
In this paper, we present a quantitative analysis of the error in the reconstruction of a 3D scene which has been captured with Synthetic Aperture Integral Imaging system. The 3D information is obtained from 2D images for which the camera parameters are unknown. The model used for calibrating the Integral Imaging camera setup is based on fuzzy systems. These systems provide the opportunity for modeling of conditions which are inherently imprecisely defined. We demonstrate that the error in the 3D reconstruction not only depends on the number of cameras, but also to their relative positions. Our model is applied to a set of images captured experimentally from a real object. A true-color real…
Design of temperature control system using conventional PID and Intelligent Fuzzy Logic controller
2015
In this paper, we present the design of temperature control for industrial heat treating furnace by using Intelligent Fuzzy Logic and PID controllers. Temperature control is important in heating processes as it can disqualify materials in terms of their physical properties when not well performed. Obviously PID temperature controller is the most used in industries to control non-linear processes. Consequently, it has been found that the output response from Fuzzy Logic is very accurate in terms of overshoot and steady state error when compared to that of PID. Moreover, both temperature controllers are modeled and simulated using MATLAB software.