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Abstract. This research presents an adaptive neuro-fuzzy system which is used in the prediction of the distance between the pantograph and contact line of the electrical locomotives used in railway transportation. In railway transportation any incident that occurs in the electrical system can have major negative effects: traffic interrupts, equipment destroying. Therefore, a prediction as good as possible of such situations is very useful. In the paper was analyzing the possibility of modeling and prediction the variation of the distance between the pantograph and the contact line using intelligent techniques IntroductionThe problem of modeling is an important step in any activity that requires the identification of an engineering solution to a real problem. Solving a new problem involves: identifying and developing a model; using techniques to find an optimal solution based on the developed model (this can be done by simulation); using the optimal solution to the needs of the real problem Modeling and simulation are the use of statistical or dynamic (timely) models to obtain data and decision making information. Modeling and simulation help reduce costs and increase product and system quality. The modeling and simulation technique is cheaper and more secure than real-world experiments in many practical situations. It is also sometimes closer to reality than traditional experiments and allowing the configuration of environmental parameters to the values encountered in the application domain. Simulation is (often) much faster than a real process, allowing for an efficient analysis of different situations (the most unfavorable case.) Once is identified and developed a model, this can be used many times.The present paper uses modeling and simulation techniques based on fuzzy logic and neural calculus having the prediction of a time series, namely the variation in time of the catenary pantograph distance to electric locomotives. For the validation of the identified model, results of measurements of electrical quantities performed on a laboratory model were used. The catenary pantograph system has a dynamic oscillatory behavior and can be disturbed by certain turbulences during operation. It has been observed that at speeds of over 180 km / h the contact between the pantograph and the catenary can be interrupted and electric arcs can occur. There is no adequate mathematical model describing this behavior. Figure 1 shows the pantograph and figure 2 shows the aliasing of this movement.

Abstract. During the electric arc furnace operation appear disturbances, which can affect the other equipments that are connected to the same power network. So it is necessary to develop models for the electric arc which characterizes the electric arc behavior in order to identify methods and solutions through which the disturbances that appear in the power network can be reduced. This paper presents two proposed models used to simulate the electric arc behavior of a 3-phase electric arc furnace which were implemented using the Simulink toolbox of Matlab. In order to facilitate the analysis of the influence of the model parameters, graphical user interfaces were implemented. Then, the simulation results were compared with known results.

This paper describes the functioning of a hardening installation with electromagnetic induction from the point of view of generating harmonics in the power distribution. The authors modeled a simplified active filter in parallel configuration in scope of reducing the effects of the generated non-sinusoidal regime. Modeling and simulation were made using PSCAD-EMTDC tool.Index Terms-Electro thermal installation, harmonic currents, active filter, total harmonic distortion.

Abstract. The asynchronous searching techniques are characterized by the fact that each agent instantiates its variables in a concurrent way. Then, it sends the values of its variables to other agents directly connected to it by using messages. These asynchronous techniques have different behaviors in case of delays in sending messages. This article depicts the opportunity for synchronizing agents' execution in case of asynchronous techniques. It investigates and compares the behaviors of several asynchronous techniques in two cases: agents process the received messages asynchronously (the real situation from practice) and the synchronous case, when a synchronization of the agents' execution is done i.e. the agents perform a computing cycle in which they process a message from a message queue. After that, the synchronization is done by waiting for the other agents to finalize the processing of their messages. The experiments show that the synchronization of the agents' execution leads to lower costs in searching for solution. A solution for synchronizing the agents' execution is proposed for the analyzed asynchronous techniques.