In the article presented we deal with an innovative approach to collaborative work and learning. This approach is called trialogical learning and has emerged from several theories that describe the creation of new knowledge, e.g. Carl Bereiter’s knowledge building approach, Yrjö Engeström’s theory of expansive learning based on Activity Theory and Nonaka and Takeuchi’s model of organizational knowledge creation. Trialogical learning is not supposed to be a ”super-theory” on the basis of these background theories but it pinpoints certain kinds of phenomena which are prevalent and central nowadays: how people organize their work for developing some shared, concrete objects. Trialogical learning is a relative new approach in education area. Theoretical as well as practical aspects of this innovative learning approach started to be researched and developed in Finland, at the University in Helsinki. From this institution the idea is being distributed now in the (not only) European educational community, e.g. within the KP-Lab project. KP-Lab project presents a unifying view (knowledge-creation perspective) of human cognition based on an assumption that learning is not just individual knowledge acquisition or social interaction, but shared efforts of transforming ideas and social practices. The KP-Lab team from Technical University of Košice (TUK) is working within the Centre for Information Technologies, Faculty of Electrical Engineering and Informatics, cooperating also with the Faculty of Economics of the same university. TUK is involved in all technological workpackages, playing as such an important role in the technological aspects of the KP-Lab integrated research activities. .

This article describes the influence of the kind of membership function on the accuracy of fuzzy logic forecasting model in the local power system. Fuzzy logic approach overcomes some problems related to practical implementations of traditional modelling and forecasting methods. This qualitative method of load forecasting can incorporate imprecise and ambiguous information in reasoning. The combination of fuzzy logic and other deterministic or stochastic methods which has recently emerged as a highly promising approach for electric load forecasting is also discussed. This paper describes the prediction algorithms and methods employed and points out the benefits gained by the use of the method.

The performance of an HVDC link is significantly impacted by the relative strength of the AC system to which it is connected. However, the interaction between AC and DC systems and the associated problems are very much dependent on the strength of the AC system relative to the capacity of the DC link. This paper explores the effect of the DC control on recovery from commutation failures in an HVDC inverter following AC system fault in line commutated thyristor inverter feeding a weak AC system. The AC system fault to which the study system is subjected is a single phase ground fault. MATLAB Simulink is used for the simulation studies.

The dynamics neglected during the identification of the process, the variation of stator resistances and cyclic inductances induce a difference between the process and the nominal mathematical model. These drifts are due to the temperature, the saturation of the magnetic circuit and the skin effect. In this case, the traditional methods such as Bode design, Nyquist design, and Nichols chart design fail to satisfy robust stability and performance. To solve this problem, an efficient robust method called the H∞ design method is used. This approach permits to achieve a successfully designed control system, which is able to maintain stability and performance level in spite of uncertainties in system dynamics. In this article, we present the field orientation control (FOC) of the permanent magnets synchronous machine (PMSM) fed by a voltage source inverter with regulated currents on the d and q axes. The field orientation control consists in regulating the flux by one component of the current and the torque by the other component. So, it is necessary to consider a reference frame attached to the rotor with direct and quadrature axes and a control law that ensure the decoupling of the torque and flux. In the case of the permanent magnets synchronous machine, if the current id is maintained null, the stator reaction flux is in quadrature with the flux produced by the permanent magnets, then the torque becomes directly proportional to the current iq and the model of the machine becomes equivalent to that of the DC machine. As a result, the model of the PMS machine is divided into two independent SISO systems.

Temperature and the resulting thermal behavior of electric power generation and distribution equipment and industrial electrical systems and processes are the most critical factors in the reliability of any operation or facility. Temperature is by far the most measured quantity in any industrial environment. For these reasons, monitoring the thermal operating condition of electrical and electromechanical equipment is considered to be key to increasing operational reliability and decreasing electrical losses.

Cisco Networking Academy proves to be a viable project in the area of education of networking professionals. All educational materials are presented in English and students are required to study in English too. Our experience shown that it is worth for the students to have a localized curriculum as well. Official translations are extremely expensive. On the other hand, many Local Academies provide some form of translation of curricula to their students. We decided to develop an environment based on Web 2.0 technologies, to provide community tools for collaborative translation of curricula and its distribution to Academy students. The paper describes basic ideas of the developed solution and presents some results in the translation of the CCNA curricula.