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The Micro-Electronics Cloud Alliance (MECA) is a European project in which eight higher education institutions and 8 enterprises are developing e-learning materials in the field of micro- and nanoelectronics. Ss. Cyril and Methodius... more
The Micro-Electronics Cloud Alliance (MECA) is a European project in which eight higher education institutions and 8 enterprises are developing e-learning materials in the field of micro- and nanoelectronics. Ss. Cyril and Methodius University — Skopje, Macedonia as a partner organization in the project participates in almost all project activities such as, need analysis, specification and development of the cloud teaching system, development of courses, conduction of pilot tests and local dissemination. The focus is on common MSc degree level courses development for the new skills needed in the multidisciplinary sector of micro- and nanotechnology. The paper describes the development of two courses (MEMS Sensors and Actuators, and Semiconductor Device Modelling and Simulation) for learning microelectronics with open educational resources shared in the cloud.
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This paper presents the modeling of a dynamic system through the System Identification Process, respectively of a wheeled mobile robot running on a flat factory terrain. The system control relies on the same control algorithms applied in... more
This paper presents the modeling of a dynamic system through the System Identification Process, respectively of a wheeled mobile robot running on a flat factory terrain. The system control relies on the same control algorithms applied in industrial controllers, Decoupled PID control and Model Predictive Control (MPC). The simulation results, and the comparison between these control algorithms, subjected to the same identified model, are presented at the end of each section.
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In this paper, we present the dynamic modelling of two differential wheeled mobile robot, and also propose an easily implementable control strategy, for stabilizing the nonlinear and nonholonomic WMR system around the desired final... more
In this paper, we present the dynamic modelling of two differential wheeled mobile robot, and also propose an easily implementable control strategy, for stabilizing the nonlinear and nonholonomic WMR system around the desired final posture. The asymptotic stability is approached by using two PI controllers. The dynamic model of WMR is used in the simulation environment of Matlab/Simulink, for testing the proposed stabilizing control strategy. The validity of control strategy is verified by the simulation results. Key words: wheeled mobile robot; dynamic modelling; nonholonomic robots; stabilization control; linear controller REFERENCES: [1] G. M. Dimirovski: “Vuk and Georgi: An Adventure into Active Systems via Mechatronics, Robotics and Manufacturing Engineering” (Plenary Lecture). In: SISY2013. Proceedings of the IEEE 11 th International Conference on Intelligent Systems and Informatics – Remembering Miomir K. Vukobratovic, (I. J. Rudas, B. Borovac, J. Fodor, General Chairs; I. St...
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Abstract A class of generalized interconnected systems, possessing similar linear structure and non linear unmatched interconnections, is studied in this paper. Hence a new topic of similarity systems research is presented. Dynamic... more
Abstract A class of generalized interconnected systems, possessing similar linear structure and non linear unmatched interconnections, is studied in this paper. Hence a new topic of similarity systems research is presented. Dynamic compensators are designed so that the closed-loop systems of the original systems and the compensators are asymptotically stable and have no impulse effect. Compensators also possess similar structures and are realized easily, so that a destroyed compensator is easily reproduced.
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Abstract Paper presents a case-study of task-oriented and set-point-oriented (combustion and heating regulation) process controls in complex industrial furnaces. An experiment in iterative development and design of control and supervision... more
Abstract Paper presents a case-study of task-oriented and set-point-oriented (combustion and heating regulation) process controls in complex industrial furnaces. An experiment in iterative development and design of control and supervision of a complex process of pipe/tubes heat processing in a large, 20 MW, four-zone, gas-fired, tunnel furnace under changing load has been elaborated. Three families of multi-variable models have been developed and identified on the grounds of experimental step and PRBS tests. Iterative identification has been applied to arrive at feasible and realistic design solutions for this multivariable process control problem. On the supervisory task-control level, the solution sought has been derived in terms of a supervisory production-rule, fuzzy-Petri-net based controller that generates commands to lower regulation control level.
ABSTRACT In societal system disputes and in direct conflict of interests, in particular, the decision making faces a basic situation resembles a combat-like situation (Figure 1). For each of the opponents ('players') has... more
ABSTRACT In societal system disputes and in direct conflict of interests, in particular, the decision making faces a basic situation resembles a combat-like situation (Figure 1). For each of the opponents ('players') has in mind and carries out own missions in the societal environment (Figure 2) Furthermore, two or more parties need to make decisions with fully or partially conflicting objectives when involved in a dispute or open conflict. And yet, by and large, decisions must be made under risk, uncertainty, and incomplete or fuzzy information based on adaptive perception knowledge (Figure 3), which may imply large amounts of linguistic and probabilistic information with missing data. In the case of two opponents, the synergy of fuzzy approach and matrix games seems rather effective for modelling such multi-criteria conflicting situations. This synergy is feasible provide the game equilibrium stability concept is conceived in compliance with an adequate uncertainty preference scheme of decision making. In the case of two scenarios or states of a conflict, the preference scheme for a given participating decision-maker has to include components for handling cases of one state strict preference over another state, equal preference between the states, and also uncertainty preference. The fuzzy modelling based procedure is employed to take into account some of the subjective attitudes of the decision makers that are difficult to model using classical game theory.
Research Interests: Mathematics and Elsevier
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Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. We describe several predictive control approaches for high consumption industrial furnace... more
Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. We describe several predictive control approaches for high consumption industrial furnace control. These furnaces are major consumers in production industries, and reducing their fuel consumption and optimizing the quality of the products is one of the most important engineer tasks. In order to demonstrate the benefits from implementation of the advanced predictive control algorithms, we have compared several major criteria for furnace control. On the basis of the analysis, some important conclusions have been drawn. 1.
In this paper we present results from prediction of data for ozone (O 3) concentrations in ambient air by using the modelling techniques of support vector ma chines (SVM) and radial basis neural networks (RBF NN). The predictions are... more
In this paper we present results from prediction of data for ozone (O 3) concentrations in ambient air by using the modelling techniques of support vector ma chines (SVM) and radial basis neural networks (RBF NN). The predictions are performed for two sho rt periods of time: for 24 hours and for one week in August and in December in 2005, in Skopje, Maced onia. The built SVM models use different kinds of kernels: polynomial and Gaussian kernels and the be st values of the free parameters of SVM kernels are chosen by examining a range of values for each of t he free parameters. This is the first attempt in Macedonia for prediction of concentrations of any a ir parameters in the ambient air. Povzetek: Podana je analiza ravni ozona v Makedonij i z metodami strojnega ucenja.
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Kalman filtering is a method for estimating state variables of a dynamic systems recursively from noise-contaminated measurements. For systems with nonlinear dynamics, a natural extension of the Linear Kalman Filter (LKF), called Extended... more
Kalman filtering is a method for estimating state variables of a dynamic systems recursively from noise-contaminated measurements. For systems with nonlinear dynamics, a natural extension of the Linear Kalman Filter (LKF), called Extended Kalman filter (EKF) is used. The Kalman filter represents one of the most popular estimation techniques for integrating signals from navigation systems, like Inertial Navigation System (INS) and Global Positioning System (GPS). However, a significant difficulty in designing a Kalman Filter (refers to both LKF and EKF) can often be traced to incomplete a priori information about R and Q matrices. It has been shown that incorrect a priori information can lead to practical divergence of the filter. The use of fuzzy-rule based adaptation scheme to cope with divergence problem is explored. The Fuzzy Logic Adaptive Controller (FLAC) was implemented in Integrated INS/GPS Navigation Systems to detect the uncertainties, adapt the Kalman Filter on-line and p...
This paper presents some results of European projects for improvement and innovation of engineering education. It summarizes the application of performance support systems, previously used only for company training, in higher education... more
This paper presents some results of European projects for improvement and innovation of engineering education. It summarizes the application of performance support systems, previously used only for company training, in higher education and discusses its advantages. The development of distributed in four European countries performance-centred learning system for information technology, telecommunication, and microelectronics is also presented. As the practice in engineering education is crucial, virtual laboratories with demonstrations, animations and simulations were developed as well as laboratories with remote access to real experiments. Finally, our recent work on the creation of microelectronics Cloud system in nine European countries is presented by an example of building cloud nodes at an installation site.
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A completed case study on fuzzy logic control of thermal processes has been carried out using a professional laboratory oven for industrial purpose as an experimental test rig. It involved system engineering design analysis, control... more
A completed case study on fuzzy logic control of thermal processes has been carried out using a professional laboratory oven for industrial purpose as an experimental test rig. It involved system engineering design analysis, control synthesis, and implementation as well as application software and signal interface design and development. The resulting expertise and lessons learned are reported in this contribution. The structure of PD type of fuzzy logic controllers is closely discussed along with synthesis issues of membership functions and knowledge rule base. Special software was developed using Microsoft Visual Studio, C++ and Visual basic for GUI for a standard PC platform. The application software designed and implemented has four modules: FIS editor, Rule Editor, Membership Function Editor and Fuzzy Controller with Rule Viewer. Quality and performance of the overall fuzzy process control system have been investigated and validated to fulfill the required quality specifications.
Research Interests: Design and Implementation
The majority of the approaches to the fault detection in rotational machines assume constant and known operating conditions. These assumptions are often violated in practice. Therefore, in this paper we propose a set of features that can... more
The majority of the approaches to the fault detection in rotational machines assume constant and known operating conditions. These assumptions are often violated in practice. Therefore, in this paper we propose a set of features that can be utilized to reveal faults in gearboxes while being robust to fluctuations in operating speed and load. The proposed feature set comprises values of two information cost functions calculated from the coefficients of the wavelet packet transform accompanied by the maximal value of the spectral kurtosis. The fault detection capabilities of the proposed feature set were evaluated on a two–stage gearbox operating under different rotational speeds and loads with different types of mechanical faults.
In this paper, we discuss an improved version of the conventional PID (Proportional–Integral–Derivative) controller, the Dynamically Updated PID (DUPID) controller. The DUPID is a control solution which preserves the advantages of the PID... more
In this paper, we discuss an improved version of the conventional PID (Proportional–Integral–Derivative) controller, the Dynamically Updated PID (DUPID) controller. The DUPID is a control solution which preserves the advantages of the PID controller and tends to improve them by introducing a quadratic error model in the PID control structure. The quadratic error model is constructed over a window of past error points. The objective is to use the model to give the conventional PID controller the awareness needed to battle the effects caused by the variation of the parameters. The quality of the predictions that the model is able to deliver depends on the appropriate selection of data used for its construction. In this regard, the paper discusses two algorithms, named 1D (one dimensional) and 2D (two dimensional) DUPID. Appropriate to their names, the former selects data based on one coordinate, whereas the latter selects the data based on two coordinates. Both these versions of the D...
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Abstract Analysis of complex systems such as non-technical system that are employed in modelling and analysis various aspects and issue of management and resolution of conflicts, and in investigating the stability of international... more
Abstract Analysis of complex systems such as non-technical system that are employed in modelling and analysis various aspects and issue of management and resolution of conflicts, and in investigating the stability of international regional and global systems. Theory of graphs and binary matrices appear to be most suitable tools for modelling the overall structure of complex systems, in general, and of systemic hierarchies, in particular. A systematic methodology has been developed for computer simulation analysis and synthesis of system hierarchies. This methodology is an improved extension ofWarfield 's technique.
Abstract An applications oriented control systems engineering approach for a class of well- posed thermal systems, e.g. industrial furnaces and ovens, that is consistent with most of theoretical results in systems and control sciences has... more
Abstract An applications oriented control systems engineering approach for a class of well- posed thermal systems, e.g. industrial furnaces and ovens, that is consistent with most of theoretical results in systems and control sciences has been elaborated and tested in designing controls for several industrial-scale furnaces. It provides a methodology for iterative learning and resolving process identification and control design for multi-variable systems within a discrete convolution framework and using truncated k-time sequence matrices of characteristic input-output modes as well as their characteristic patterns and singular characteristic patterns, starting with standard non-parametric process time-domain models identified under operating conditions. Within computer process control environment and for practical engineering and maintenance reasons, digital implementations are sought in terms of partial steady-state decoupling and two-term laws or combination of certain MIMO and SISO controls. The pusher furnace in Skopje Steelworks is used to illustrate this methodological approach
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The min–max robust control synthesis for uncertain nonlinear systems is solved using Takagi–Sugeno fuzzy model and fuzzy state observer. Existence conditions are derived for the output feedback min–max control in the sense of Lyapunov... more
The min–max robust control synthesis for uncertain nonlinear systems is solved using Takagi–Sugeno fuzzy model and fuzzy state observer. Existence conditions are derived for the output feedback min–max control in the sense of Lyapunov asymptotic stability and formulated in terms of linear matrix inequalities. The convex optimization algorithm is used to obtain the minimum upper bound on performance and the optimum parameters of min–max controller. The closed-loop system is asymptotically stable under the worst case disturbances and uncertainty. Benchmark of inverted pendulum plant is used to demonstrate the robust performance within a much larger equilibrium region of attraction achieved by the proposed design.
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This paper is oriented toward presenting the advanced predictive control methods in thermal processes which have been developed and/or practically implemented at the ASE Institute in FEEIT Skopje. The thermal processes usually have high... more
This paper is oriented toward presenting the advanced predictive control methods in thermal processes which have been developed and/or practically implemented at the ASE Institute in FEEIT Skopje. The thermal processes usually have high fuel consumption and therefore the optimization of the fuel costs is extremely important. With reducing of these costs we dramatically reduce the costs of the final product. In such direction, the advanced control methods for thermal processes usually lean toward faster response and increased robustness, in this case, using predictive techniques.
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Abstract A design of fuzzy model-based predictive control for industrial furnaces has been derived and applied to the model of three-zone 25 MW RZS pusher furnace at Skopje Steelworks. The fuzzy-neural variant of Takagi-Sugeno fuzzy... more
Abstract A design of fuzzy model-based predictive control for industrial furnaces has been derived and applied to the model of three-zone 25 MW RZS pusher furnace at Skopje Steelworks. The fuzzy-neural variant of Takagi-Sugeno fuzzy model, as an adaptive neuro-fuzzy implementation, is employed as a predictor in a predictive controller. In order to build the predictive controller the adaptation of the fuzzy model using dynamic process information is carried out. Optimization procedure employing a simplified gradient technique is used to calculate predictions of the future control actions.
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In this paper we present a complete solution for remote automation of the hydro-system Studencica in Kicevo. With the implementation of the system for control and data acquisition, we have significantly reduced the expenses for... more
In this paper we present a complete solution for remote automation of the hydro-system Studencica in Kicevo. With the implementation of the system for control and data acquisition, we have significantly reduced the expenses for maintenance of the system.
The modern SCADA system (Supervisory Control And Data Acquisition) is used to improve the effiecency of the power plant by collecting data for process values using sensors and transdusers, display this data on the plant display and... more
The modern SCADA system (Supervisory Control And Data Acquisition) is used to improve the effiecency of the power plant by collecting data for process values using sensors and transdusers, display this data on the plant display and sending the commands to actuators. Using the historical data the model of the power plant can be created. Alarm processing and archiving. Trends. Security in modern SCADA systems. Implementation of modern SCADA system.
... con dition, all of the terms involved in time delay must be enlarged to a scalar function on current system states by using Razumikhin Theorem (Hale ... (8) can stabilize the closed-loop system (l), where II = 1 (AP + I PAT) + 2£EET +... more
... con dition, all of the terms involved in time delay must be enlarged to a scalar function on current system states by using Razumikhin Theorem (Hale ... (8) can stabilize the closed-loop system (l), where II = 1 (AP + I PAT) + 2£EET + 2£AdA + 2£EdEI + Q1, MJ is the square root of ...
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Abstract This paper addresses the issues of passivity and feedback passivation of switched nonlinear systems via multiple storage functions. The concept of storage-like functions for switched systems is presented. A sufficient condition... more
Abstract This paper addresses the issues of passivity and feedback passivation of switched nonlinear systems via multiple storage functions. The concept of storage-like functions for switched systems is presented. A sufficient condition for passivity of switched nonlinear systems is given via multiple storage functions under some switching signal. Then, the result is extended to find conditions under which a switched system is feedback equivalent to a passive switched system. Furthermore, passivity of switched cascade systems is ...
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ABSTRACT The min-max robust control synthesis for uncertain nonlinear systems is solved using Takagi-Sugeno fuzzy model and fuzzy state observer. Existence conditions are derived for the output feedback min-max control in the sense of... more
ABSTRACT The min-max robust control synthesis for uncertain nonlinear systems is solved using Takagi-Sugeno fuzzy model and fuzzy state observer. Existence conditions are derived for the output feedback min-max control in the sense of Lyapunov asymptotic stability and formulated in terms of linear matrix inequalities. The convex optimization algorithm is used to obtain the minimum upper bound on performance and the optimum parameters of mini-max controller. The close-loop system is asymptotically stable under the worst case disturbances and uncertainty. Benchmark of inverted pendulum plant is used to demonstrate the robust performance within a much larger equilibrium region of attraction achieved by the proposed design.
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ABSTRACT A set of linear multivariable models for a 20 MW, large industrial, gas-fired furnace, used in the production of welded steel pipes, has been developed and identified on the grounds of experimental step and PRBS tests.... more
ABSTRACT A set of linear multivariable models for a 20 MW, large industrial, gas-fired furnace, used in the production of welded steel pipes, has been developed and identified on the grounds of experimental step and PRBS tests. Uncertainty within models is represented in terms of delays and steady-state gains. Iterative identification and control design investigation has been applied to arrive at a feasible and realistic solution for this multivariable process control problem. Extensive simulation experiments were carried out using the convolution-based simulation language, and a comparison analysis of several control system design strategies has led to a couple of implementable alternatives. A robust multivariable computer process control has been synthesised that gives satisfactory transient responses and minimal fuel consumption during furnace load changes. Stability property or ultimate boundedness of outputs has been preserved within all designs, both the ideal nonfeasible and the realistic feasible ones
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Abstract The problem of quadratic stability for a class of uncertain nonlinear systems using Takagi-Sugeno fuzzy model is solved and certain relaxed conditions are derived. Firstly, a new robust quadratic stability condition via designing... more
Abstract The problem of quadratic stability for a class of uncertain nonlinear systems using Takagi-Sugeno fuzzy model is solved and certain relaxed conditions are derived. Firstly, a new robust quadratic stability condition via designing state feedback controller for TS fuzzy system with uncertainties is derived. This condition is represented in the form of LMI and it is shown to be less conservative than similar known relaxed quadratic stabilization conditions in recent literature. Secondly, a dynamic output feedback control design for complex ...