Implementation of new equipment for the laboratory exercises – Testing of low-voltage electrical installations

This study was supported by the Ministry of Education, Science and Technological Development of the Republic of Serbia, and these results are parts of the Grant No. 451-03-68/2022-14/200132 with University of Kragujevac - Faculty of Technical Sciences Čačak.This paper presents the new equipment that is used for laboratory exercises in the subject of Electrical installations and lighting at the undergraduate academic and professional studies in the Faculty of Technical Sciences in Čačak. Multifunctional electrical installation safety testers for testing domestic and industrial electrical installations were presented. A demonstration board that provides simulation of different types of faults in electrical installations is also presented. As an illustrative example, the paper presents the procedure and results obtained during the realization of the exercise - Measurement of ground fault loop impedance in TT and TN earthing systems and checking the conditions for automatic disconnection of supply.Publishe

Comparative analysis of objective techniques for criteria weighing in two MCDM methods on example of an air conditioner selection

This paper deals with comparative analysis of two different types of objective techniques for criteria weighing: Entropy and CRITIC and two MCDM methods: MOORA and SAW on example of an air conditioner selection. We used six variants for calculation of normalized performance ratings. Results showed that the decision of the best air conditioner was basically independent of the MCDM method used, despite the applied technique for determination of criteria weights. Complete ranking within all of the combinations of methods and techniques with diverse ratio calculation variants showed that the best ranked air conditioner was A7, while the worst ones were A5 and A9. Significant positive correlation was obtained for almost all the pairs of variants in all the combinations except for the MOORA - CRITIC combination with SAW - Entropy combination to have the highest correlations between variants (p < 0.01)

THE CHOICE OF COMPACT FLUORESCENT LIGHT BULBS USING THE METHOD OF SAW AND CP

Multi-criteria analysis allows making decision in conflict conditions, when there are multiple alternatives and criteria, some of which should be maximized and some minimized. Therefore, in solving multicriteria tasks should use flexible instruments, by character of pure mathematical optimization techniques. The paper discusses choice of compact fluorescent light bulbs through multi-criteria decision-making methods, specifically in this case, the method of SAW and the method compromise programming (CP)

Cluster analysis of knowledge sources in standardized electrical engineering subfields

The paper presents a cluster analysis of innovation of knowledge sources based on the standards in the field of Electrical Engineering. Both local (SRPS) and global (ISO) knowledge sources have been analysed with the aim of innovating a Knowledge Base (KB). The results presented indicate a means/possibility of grouping the subfields within a cluster. They also point to a trend or intensity of knowledge source innovation for the purpose of innovating the KB that accompanies innovations. The study provides the possibility of predicting necessary financial resources in the forthcoming period by means of original mathematical relations. Furthermore, the cluster analysis facilitates the comparison of the innovation intensity in this and other (sub)fields. Future work relates to the monitoring of the knowledge source innovation by means of KB engineering and improvement of the methodology of prediction using neural networks

Cluster analysis of knowledge sources in standardized electrical engineering subfields

The paper presents a cluster analysis of innovation of knowledge sources based on the standards in the field of Electrical Engineering. Both local (SRPS) and global (ISO) knowledge sources have been analysed with the aim of innovating a Knowledge Base (KB). The results presented indicate a means/possibility of grouping the subfields within a cluster. They also point to a trend or intensity of knowledge source innovation for the purpose of innovating the KB that accompanies innovations. The study provides the possibility of predicting necessary financial resources in the forthcoming period by means of original mathematical relations. Furthermore, the cluster analysis facilitates the comparison of the innovation intensity in this and other (sub)fields. Future work relates to the monitoring of the knowledge source innovation by means of KB engineering and improvement of the methodology of prediction using neural networks

Artificial neural network model for predicting air pollution. Case study of the Moravica district, Serbia

© 2018 Technical University of Wroclaw. All rights reserved. An example of artificial neural network model for predicting air pollution has been presented. The research was conducted in Serbia, the Moravica District, on the territory of two municipalities (Lucani and Ivanjica) and the town Cacak. The level of air pollution was classified by a neural network model according to the input data: municipality, site, year, levels of soot, sulfur dioxide (SO2), nitrogen dioxide (NO2) and particulate matter. The model was evaluated using a lift chart and a root mean square error (RMSE) has been determined, whose value was 0.0635. A multilayer perceptron has also been created and trained with a back propagation algorithm. The neural network was tested with the data mining extensions (DMX) queries. The results have been obtained for air pollution based on new input data that can be used to predict the level of pollution in future if new measurements are carried out. A web-based application was designed for displaying the results

Multi-criteria decision making method of minimal suitable values

This paper presents a conceptual and mathematical model of a multi-criteria decision making process in which the information about decision maker's preferences is expressed in the form of minimal suitable values