Search results for "Control Engineering"
showing 10 items of 435 documents
Adaptive output feedback neural network control of uncertain non-affine systems with unknown control direction
2014
Abstract This paper deals with the problem of adaptive output feedback neural network controller design for a SISO non-affine nonlinear system. Since in practice all system states are not available in output measurement, an observer is designed to estimate these states. In comparison with the existing approaches, the current method does not require any information about the sign of control gain. In order to handle the unknown sign of the control direction, the Nussbaum-type function is utilized. In order to approximate the unknown nonlinear function, neural network is firstly exploited, and then to compensate the approximation error and external disturbance a robustifying term is employed. …
H<inf>&#x221E;</inf> controller design for the synchronization of a hyper-chaotic system
2013
In this paper, the robust control on the synchronization of a hyper-chaotic system is investigated. Based on Lyapunov stability theory and linear matrix inequality techniques, the multi-dimensional and the single-dimensional robust H∞ synchronization controllers are constructed for the possible application in practical engineering. Some numerical simulations are provided to demonstrate the effectiveness of the presented controllers.
Influence of the Preparation Method on Planar Perovskite CH 3 NH 3 PbI 3-x Cl x Solar Cell Performance and Hysteresis
2017
The present research has been supported by the State Research Programme “LATENERGI” and National Research Programme “Multifunctional Materials and Composites, Photonics and Nanotechnology (IMIS2)”.
A Computer Control System for the Hydraulic Stand MZPK 100 for Biaxial Fatigue Testing
2006
This paper presents a two-channel digital control system for the hydraulic stand MZPK 100 designed for fatigue tests of cruciform specimens under biaxial tension-compression. In the past, the fatigue test stand MZPK 100 was provided with unreliable analog control power cubicles. Application of the computer with an analog and digital input-output signal path board, Matlab/Simulink software and a new control box equipped with the necessary electronic subassemblies (responsible for proper switching of the hydraulic supplier, command electrovalves, conditioning of signals from sensors and so on) enables replacement of the old analog system by a new two-channel digital control system. Nowadays, …
Optimal control circuitry design for the digital p53 dynamics in cancer cell and apoptosis
2009
AbstractExperimental work and theoretical models deduce a "digital" response of the p53 transcription factor when genomic integrity is damaged. The mutual influence of p53 and its antagonist, the Mdm2 oncogene, is closed in feedback. This paper proposes an aerospace architecture for translating the p53/Mdm2/DNA damage network into a digital circuitry in which the optimal control theory is applied for obtaining the requested dynamic evolutions of some considered cell species for repairing a DNA damage. The purpose of this paper is not to improve the analysis of the actual mathematical models but to demonstrate the usefulness of such digital circuitry design capable to predict and detect the …
Soft Sensor Transferability between Lines of a Sulfur Recovery Unit
2021
Abstract Soft Sensors (SSs) are mathematical models that allow real-time estimation of hard-to-measure variables as a function of easy-to-measure ones in an industrial process, emulating the behavior of existing sensors when they are, for instance, taken off for maintenance. The Sulfur Recovery Unit (SRU) from a refinery is taken in exam. Recurrent Neural Networks (RNN) can capture the nonlinearity of such process but present a high complexity training and a very time-consuming structure optimization. For this reason, strategies to use pre-existing models are here examined by testing the transferability of the SSs between two parallel lines of the process.
Drilling Systems: Stability and Hidden Oscillations
2013
There are many mathematical models of drilling systems Despite, huge efforts in constructing models that would allow for precise analysis, drilling systems, still experience breakdowns. Due to complexity of systems, engineers mostly use numerical analysis, which may lead to unreliable results. Nowadays, advances in computer engineering allow for simulations of complex dynamical systems in order to obtain information on the behavior of their trajectories. However, this simple approach based on construction of trajectories using numerical integration of differential equations describing dynamical systems turned out to be quite limited for investigation of stability and oscillations of these s…
A thermoeconomics-based approach to the integrated optimization of design and operation for decentralised energy systems and variable load conditions
2006
The many comprehensive approaches formulated for the optimization of large industrial energy systems have been rarely applied to small and medium scale units, because of the difficulties in handling a continuously variable energy demand and of the lower margins for energy and emissions saving. Today, the growing interest for decentralised energy systems in the civil sector stimulates major efforts for the optimization of such plants, with a particular focus on the control system and on a management strategy able to exploit the opportunities existing in the free energy market. In this paper a methodology is proposed for the optimization of design and operation of variable demand systems supp…
Design of a Permanent Magnet Synchronous Generator using Interactive Multiobjective Optimization
2017
We consider an analytical model of a permanent magnet synchronous generator and formulate a mixed-integer constrained multiobjective optimization problem with six objective functions. We demonstrate the usefulness of solving such a problem by applying an interactive multiobjective optimization method called NIMBUS. In the NIMBUS method, a decision is iteratively involved in the optimization process and directs the solution process in order to find her/his most preferred Pareto optimal solution for the problem. We also employ a commonly used noninteractive evolutionary multiobjective optimization method NSGA-II to generate a set of solutions that approximates the Pareto set and demonstrate t…
Cascade Controller Including Backstepping for Hydraulic-Mechanical Systems
2012
Abstract Development of a cascade controller structure including adaptive backstepping for a nonlinear hydraulic-mechanical system is considered in this paper where a dynamic friction (LuGre) model is included to obtain the necessary accuracy. The paper compares the performance of two variants of an adaptive backstepping tracking controller with earlier results. The new control architecture is analysed and enhanced tracking performance is demonstrated when including the extended friction model. The complexity of the backstepping procedure is significantly reduced due to the cascade structure. Hence, the proposed control structure is better suited to real-time implementation.