The paper deals with the innovative ways of nonstandard, simplifying applications of the valid method for evaluating uncertainties in measurement results and with the definition of conditions of their usability. The evaluation of a substitute criterion for measurement accuracy by means of a relative difference between the measurand and its reference value is proposed. This nonstandard relative uncertainty is comparable with the overall relative standard uncertainty in the measurement result, and thus the evaluation of it enables other simplifications in the calculations of measurement result uncertainties. The use of the simplified evaluation of measurement results is illustrated in two experiments in measurement of the coefficient of thermal conductivity of an insulating material newly developed for the needs of building practice, namely measurement using commercial instruments, and measurement using a newly developed original measuring instrument.

This paper from the field of environmental chemistry offers an innovative use of sorbents in the treatment of waste industrial water. Various industrial activities, especially the use of technological fluids in machining, surface treatment of materials, ore extraction, pesticide use in agriculture, etc., create wastewater containing dangerous metals that cause serious health problems. This paper presents the results of studies of the natural zeolite clinoptilolite as a sorbent of copper cations. These results provide the measurement of the sorption kinetics as well as the observed parameters of sorption of copper cations from the aquatic environment to the clinoptilolite from a promising Slovak site. The effectiveness of the natural sorbent is also compared with that of certain known synthetic sorbents.

This work evaluates the possibility of identifying mechanical parameters, especially upper and lower yield points, by the analytical processing of specific elements of the topography of surfaces generated with abrasive waterjet technology. We developed a new system of equations, which are connected with each other in such a way that the result of a calculation is a comprehensive mathematical-physical model, which describes numerically as well as graphically the deformation process of material cutting using an abrasive waterjet. The results of our model have been successfully checked against those obtained by means of a tensile test. The main prospect for future applications of the method presented in this article concerns the identification of mechanical parameters associated with the prediction of material behavior. The findings of this study can contribute to a more detailed understanding of the relationships: material properties-tool properties-deformation properties.

In this study, a new generalized regression neural network model for predicting the curing characteristics of rubber blends with different contents of carbon black filler cured at various temperatures is proposed for the first time The carbon black contents in the rubber blend and cure temperature were used as input parameters, while the minimum and maximum elastic torque, scorch time, and optimal cure time, obtained from the analysis of 11 rheological cure curves registered at 10 various temperatures, were considered as output parameters of the model. A special pre-processing procedure of the experimental input and target data and the training algorithm is described. Less than 55% of the experimental data were used to significantly reduce the total number of input and target data points needed for training the model. Satisfactory agreement between the predicted and experimental data, with a maximum error in the prediction not exceeding 5%, was found. It is concluded that the generalized regression neural network is a powerful tool for intelligently modelling the curing process of rubber blends even in the case of a small dataset, and it can find a wide range of practical applications in the rubber industry.

Mobile robots with differential chassis are very often used because of simple construction and a smaller number of drive and sensors elements. For practical applications, it is necessary to know the kinematic and dynamic structure of the differential mobile robot. This paper deals with identification of the dynamics of the differential robotic platform, using differential kinematics. Electro-optical rpm sensors obtain required values such as speed of the driven wheels. Identification of dynamic system is used to determine the dynamic characteristics of power subsystem of developed EN 20 robot, whose control subsystem is created by single-chip microcontroller. Response of the dynamic system is monitored along with the peripheral velocity of the right and left drive wheels. Incremental encoders that work on optics principle measure the speeds of both wheels. It was necessary to calibrate the sensors and obtain constants for precise speed determination. The monitored system with the dumped oscillation characteristic is approximated by a system with the inertia of the 2 nd order. Dynamic system parameters are found. The system approximation is suitable for given evolution of circumferential speeds of the right and left wheels. This is confirmed by the quantitative determination coefficients R 2. The equations for calculating peripheral velocities of driving wheels are applied to the system of the differential equations for the differential chassis. A mathematical model of the mobile robot EN20 was obtained for testing control algorithms, where a robot is equipped with sensory systems and it is designed for interior conditions. Fuzzy controller with 49 interference rules is used to control the mobile robot. The real mobile robot path matches the path determined according to simulation model.

Wider use of alternative energy sources is a real requirement of sustainable economy – not only from the point of view of limited natural resources –, and there is a question what is the knowledge, the attitude of young generation. As there is a strong connection between the use of renewable energy and sustainability, the issues must be examined together. On the other hand it can be observed that there is a tendency that people are becoming more open and inquiring towards renewable energy sources, and environment protection is considered as a very important task. The main goals of the research were to examine the knowledge of the young generation taking part in higher education on sustainability and alternative energy, and to find out their attitudes to the use of different alternative energy sources. Also, our hypotheses said that the level of knowledge of sustainability and their attitudes to the environment issues are connected. We compared the results of two surveys carried out in 2014 among the students of a Hungarian and a Slovak higher educational institute. According to the primary results it can be stated that the increasing environmental awareness of young generation is visible, although as for the concepts of sustainability and their knowledge on alternative energy sources, as well as their expectations for the future, there was no significant correlation between their opinions in the Hungarian sample. It was proved that they have open minds towards environmental consciousness, and follow the renewable energy sources with attention. A bit more than a half of the sample has real knowledge on sustainability – we mean the three-pillars model here –, more the mail interview has higher knowledge and for the future they thought the question as a very important one. Considerable majority of the respondents, compared to their capabilities, try to live environmentally-sound life, will do more than one thing to save their environment, although also some negative responses slightly appeared in the received results. Primary results of the Slovak sample are similar; respondents do similar measures for environment at their households as their Hungarian colleagues, but with different priority. Concerning the knowledge of concept of “green economy”, “blue economy” and the “non-growth”, it can be summarized that the awareness is evident but in many cases, there is just few information and weak knowledge connected with the terminology and practical consequences. We think it is an important task of education to increase the awareness of young people on sustainable energy use and to let them accustomed to the thought of green economy and non-growth theories, since the expansion of knowledge may help in the development of a more positive attitude, which will then, hopefully, encourage their actions in the future.

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