Electrical drives with single-phase and three-phase induction motors have been dominant in electromechanical energy conversion in industrial, residential and automotive applications. So far the using of induction motor in these sectors has been a good choice because of its reliability, long life, simple structure, stability, etc. Technological progress in magnetic material technology, power electronics, integrated circuits and microcontrollers have enabled alternative motor technologies such as brushless direct current (BLDC) motors. BLDC motor possesses many advantages comparing with induction motor also DC motor. The using of intelligent control methods improves its performance. These reasons bring to an increasing of the application of this motor in many sectors.  The paper aims to show a way of increasing the efficiency of electrical drives through replacing the induction motor with the BLDC motor. In the paper is  compared a permanent magnet based three-phase brushless DC motor with single phase induction motor used in fan application in terms of efficiency. The analysis is specifically related to low power fan applications. Based on the experimental results presented in the paper is clearly noticed that BLDC motors used in fan application can increase efficiency and bring energy saving up to 35% compared to three-phase induction motors.

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In this paper the use of student's curiosity to explore the virtual reality models in the World Wide Web is proposed as a new learning approach of engineering.Students were randomly assigned in two groups of 15 persons: one group shall use a virtual model downloaded from Web for the case study and the other no. Both groups of students have completed the same work assignment and have received the same instructions.While the results did not show that the students who completed the work with the virtual model performed better than their colleagues, there was a promising trend in favor of the use of the model. Students using the virtual model reported a better appreciation of real environment. The virtual model, when compared to written text, has the potential to encourage students to spend more time learning material because it is engaging and realistic.

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