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This paper presents a method for mapping and analysis of electromagnetic background in an urban area. The uniqueness of our environment causes the inability to simulate electromagnetic fields of the real world as there is an unknown amount of sources and a near infinite amount of obstacles that could obscure the traveling wave or bounce it in a different direction altogether. The proposed method allows mapping an area of 64 hectares in less than 24 hours using only one person, antenna, software-defined radio, laptop, and optionally external drive to store data, which ensures the possibility of having multiple setups to multiply results. The general analysis of gathered data consists of three parts. The first is the compression ratio, a valuable byproduct of data compression for long-term storage. The second uses geographical locations to determine variance by distance, in a straight line and a cluster. The final tool for analysis is a Pearson's and Kendall's correlations to a baseline measurement to find potential errors and/or anomalies within a data set.

Electromagnetic compatibility is a significant problem for electronic system developers, especially cabling, which is often the weakest link of the assembly, therefore a bigger emphasis is put on its securing. Recently, a significant progress has been achieved in synthetic electromagnetically lossy materials. Therefore, new cable designs using these cable sheath materials can be soon expected both in applied research and in development. At the same time, reliable measurements of such shielding effectiveness are needed, especially in terms of the far field. While most publications about synthetic electromagnetic lossy materials deal with their measurement via coaxial transmission lines (the ASTM method), far-field measurements have not been sufficiently discussed. In this paper, several phenomena related to this topic are discussed, further, an experiment testing two different cable specimens is realized and the results are compared. The paper discusses fundamental issues of far EM field generated by power supply cables fed by radio frequency interferences.

The power frequency magnetic field immunity test is a common test applied to a large variety of devices that must be checked for electromagnetic compatibility. Implementing this test is not difficult since it involves working with frequencies at which the generated magnetic field can be considered quasi-stationary. Considering the high price level of devices intended for use in electromagnetic compatibility laboratories, it may be worth contemplating assembling the equipment for this test on one's own. This paper includes a discussion on the requirements given by the relevant standards and their implications for the design of the test signal generator. Additionally, a complete design process for such equipment is provided, along with a discussion on the possibility of further improvements. The design of the test coil is adapted to allow its excitation from a powerful low-frequency amplifier, which opens up possibilities for the use of more advanced drivers. However, the test coil can also be powered using a normal mains transformer, simplifying the design of the entire device

This paper discusses the use of the terrestrial multi-frame photogrammetry method. This method is applied to a group of plants in a natural environment of a greenhouse. Image data is captured by two sensing devices with different types of lenses. Image data is used for the realistic 3D reconstruction of objects into a 3D model. In this experiment, we work primarily with the created point cloud.

This paper presents the results of our experiment, which consisted in measurement of the shielding effectiveness of a camera enclosure that was designed and constructed in order to increase thesusceptibility of a camera against external electromagnetic fields. All activities, from defining of requirements to final design and measurements, were performed in the Laboratory of Electromagnetic Compatibility at the Faculty of Applied Informatics of Tomas Bata University in Zlín. The hereby described approach allowed to utilize standardized laboratory equipment that is normally used for device susceptibility test to radiated electric field. The measurement was made inside a semi-anechoic room additionally damped by absorbers placed on its floor. When configuring the experiment, relevant EMC standards EN 55016 and EN 61000-4-3 were considered. Although the uncertainty tolerances, allowed by the relevant standards, were quite high for measurements in such rooms, the results obtained by the experiment matched the theoretical expectations quite satisfactorily. © 2021 Petr Skočík et al., published by Sciendo.

This paper presents the results of our experiment, which consisted in measurement of the shielding effectiveness of a camera enclosure that was designed and constructed in order to increase thesusceptibility of a camera against external electromagnetic fields. All activities, from defining of requirements to final design and measurements, were performed in the Laboratory of Electromagnetic Compatibility at the Faculty of Applied Informatics of Tomas Bata University in Zlín. The hereby described approach allowed to utilize standardized laboratory equipment that is normally used for device susceptibility test to radiated electric field. The measurement was made inside a semi-anechoic room additionally damped by absorbers placed on its floor. When configuring the experiment, relevant EMC standards EN 55016 and EN 61000-4-3 were considered. Although the uncertainty tolerances, allowed by the relevant standards, were quite high for measurements in such rooms, the results obtained by the experiment matched the theoretical expectations quite satisfactorily. © 2021 Petr Skočík et al., published by Sciendo.

This paper describes a voltage controlled amplifier with linearized response to the controlling voltage and discusses its harmonic distortion. As a controlling element, a JFET transistor has been utilized. The design of the amplifier has been made with the aid of Maple mathematical software and National Instruments Multisim circuit simulator. During the simulations, it was found that the controlling transistor would probably introduce significant distortion into the signal path. Therefore a set of measurements on real circuit was made in order to verify that the SPICE model of the transistor provided relevant results during the simulation. Both, the simulated and the really measured parameters of the amplifier are discussed within the framework of this paper. ©2020 IEEE

This paper describes a voltage controlled amplifier with linearized response to the controlling voltage and discusses its harmonic distortion. As a controlling element, a JFET transistor has been utilized. The design of the amplifier has been made with the aid of Maple mathematical software and National Instruments Multisim circuit simulator. During the simulations, it was found that the controlling transistor would probably introduce significant distortion into the signal path. Therefore a set of measurements on real circuit was made in order to verify that the SPICE model of the transistor provided relevant results during the simulation. Both, the simulated and the really measured parameters of the amplifier are discussed within the framework of this paper.

The paper describes electronic vibration monitoring module (EVM) that can be used as standalone diagnostic system or as a part of a complex modular concept of engine electronic control (EEC/FADEC) with aircraft health monitoring system. We present a new generation of EVM for modern small turboprop engines and their vibration diagnostics which has been developed by Unis, a.s. in cooperation with Brno University of Technology and Tomas Bata University in Zlin. © 2020 University of West Bohemia.

This paper describes a voltage controlled amplifier with linearized response to the controlling voltage and discusses its harmonic distortion. As a controlling element, a JFET transistor has been utilized. The design of the amplifier has been made with the aid of Maple mathematical software and National Instruments Multisim circuit simulator. During the simulations, it was found that the controlling transistor would probably introduce significant distortion into the signal path. Therefore a set of measurements on real circuit was made in order to verify that the SPICE model of the transistor provided relevant results during the simulation. Both, the simulated and the really measured parameters of the amplifier are discussed within the framework of this paper.

This paper describes a voltage controlled amplifier with linearized response to the controlling voltage and discusses its harmonic distortion. As a controlling element, a JFET transistor has been utilized. The design of the amplifier has been made with the aid of Maple mathematical software and National Instruments Multisim circuit simulator. During the simulations, it was found that the controlling transistor would probably introduce significant distortion into the signal path. Therefore a set of measurements on real circuit was made in order to verify that the SPICE model of the transistor provided relevant results during the simulation. Both, the simulated and the really measured parameters of the amplifier are discussed within the framework of this paper. ©2020 IEEE

The paper describes electronic vibration monitoring module (EVM) that can be used as standalone diagnostic system or as a part of a complex modular concept of engine electronic control (EEC/FADEC) with aircraft health monitoring system. We present a new generation of EVM for modern small turboprop engines and their vibration diagnostics which has been developed by Unis, a.s. in cooperation with Brno University of Technology and Tomas Bata University in Zlin. © 2020 University of West Bohemia.

The paper aims at the investigation of a liquid electrolyte effect on electromagnetic radiation. The liquid electrolyte could represent an interesting solution against electromagnetic interference for devices using transparent covers, such as security cameras. Currently, the way how to protect transparent areas is a fine metallic grid or polymer material; however, this solution could reduce the transparency through the protected part. The paper describes different types of electrolytes and compares their shielding effectiveness. The experiment includes a plastic packing, metallic electrodes, liquids, laboratory power supply, a coaxial transmission line with receiving and transmitting conductors, source of electromagnetic radiation, and test receiver. The liquid consists of weak and strong acids and bases, such as acetic acid, sulfuric acid or sodium chloride which have different conductivity. There are also various materials for electrodes affecting the conductivity and consequently, the ability of the electrolyte to eliminate the effects of electromagnetic interference. The kind of electrode affects the amount of received and delivered ions between anode and cathode. Shielding effectiveness of electrolyte depends on more unstable parameters compared to conventional metal materials. Temperature and concentration of solution affect the electrolyte conductivity; thereby, the reproducibility could be problematic. Strong electrolytes initially have a rapid increase in conductivity; however, high amounts of ions cause their interaction and decrease in conductivity. Weak electrolytes have a similar course, but the conductivity achieves many times lower values. Measurement is provided according to the ASTM D4935 methods, and it involves a discontinued inner and flanged outer conductor. Samples and the conductors are isolated from external sources of electromagnetic interference by special absorbent materials. The conclusion describes the contribution of the paper. © 2019 I

Active filters based on RC components together with operational amplifiers are quite common functional blocks to be met across different branches of electronics design. During the past, their topology has settled on several well-known and effective solutions. As an example, Sallen-Key or Multiple Feedback topology can be named. The designers can find a huge number of “cookbooks”. According to them they can find help with designing their filters. However, the theory described in these cookbooks usually fits ideal operational amplifiers in a good manner, but, unfortunately, the real parameters of the operational amplifiers may spoil the real behaviour of the design significantly. This problem occurs especially at very high frequencies that are typical for injection of electromagnetic interferences into low frequency signal lines. The authors of this paper have tested several antialiasing (low-pass) filter designs and provide results of measurement at real filters compared to the simulations. Moreover, they provide a discussion on why the results of the simulation do not fit the real behaviour of the filters and suggest improvements in the design of the low pass filters in that way so their utility value was improved. © 2019, Danube Adria Association for Automation and Manufacturing, DAAAM. All rights reserved.

The paper aims at the investigation of a liquid electrolyte effect on electromagnetic radiation. The liquid electrolyte could represent an interesting solution against electromagnetic interference for devices using transparent covers, such as security cameras. Currently, the way how to protect transparent areas is a fine metallic grid or polymer material; however, this solution could reduce the transparency through the protected part. The paper describes different types of electrolytes and compares their shielding effectiveness. The experiment includes a plastic packing, metallic electrodes, liquids, laboratory power supply, a coaxial transmission line with receiving and transmitting conductors, source of electromagnetic radiation, and test receiver. The liquid consists of weak and strong acids and bases, such as acetic acid, sulfuric acid or sodium chloride which have different conductivity. There are also various materials for electrodes affecting the conductivity and consequently, the ability of the electrolyte to eliminate the effects of electromagnetic interference. The kind of electrode affects the amount of received and delivered ions between anode and cathode. Shielding effectiveness of electrolyte depends on more unstable parameters compared to conventional metal materials. Temperature and concentration of solution affect the electrolyte conductivity; thereby, the reproducibility could be problematic. Strong electrolytes initially have a rapid increase in conductivity; however, high amounts of ions cause their interaction and decrease in conductivity. Weak electrolytes have a similar course, but the conductivity achieves many times lower values. Measurement is provided according to the ASTM D4935 methods, and it involves a discontinued inner and flanged outer conductor. Samples and the conductors are isolated from external sources of electromagnetic interference by special absorbent materials. The conclusion describes the contribution of the paper. © 2019 I

Currently, shielding effectiveness represents a fundamental property of materials designed to resist electromagnetic fields effect. There are many materials suitable for shielding; however, the authors decided to use recyclable plastic materials whose surface was provided with gold or carbon nano-layer. The experiment aimed at determining the influence of conductive material nano-layers and application to commercially available security products.

In order to deepen students' practical knowledge and understanding of the “Computer Networks” subject, a Monitoring Network System was developed that is able to read, collect and distribute data describing real technological processes. The Monitoring System design is based on Client/Server architecture. The model is represented by the real chemical reactor, which was created for the study of the enzymatic hydrolysis of potentially hazardous chrome-tanned wastes generated during leather manufacturing. Final system should be implemented at the university to the graduates and the system should be modular with possible communication support. The setup of the monitoring system comes with all needed explanation and procedures. © 2018, World Scientific and Engineering Academy and Society. All rights reserved.

In recent years, electromagnetic interference has become a severe problem for electronic and electric devices design. That has led to an increase in demand for electromagnetic protection. However, there still exists a lot of devices sensitive to electromagnetic field effect, and one of them is security camera representing a crucial factor in the security area. The paper deals with the design of electromagnetically shielding grid for security cameras lenses. The basis of the experiment is the CST Microwave Studio simulation tool used to obtain the theoretical shielding effectiveness results which are subsequently verified by practical measurements using coaxial lines. © 2018 IEEE.

Electromagnetic interference has become a severe problem for electronic and electrical devices, especially for security cameras which are significantly sensitive to electromagnetic field effects. Therefore, there was born an idea to create shielding enclosure which protects these devices against the radiated field. This task was realized by the evolutionary algorithm included in the computational process of optimizing shielding effectiveness. © 2018 IEEE.

This document provides real data obtained inside the semi anechoic room Frankonia SAC 3 plus that is certified for measurement of electromagnetic interferences and performing of electromagnetic susceptibility tests in the range from 30 MHz up to 18 GHz. The hereby presented data describe the response of the semi anechoic room to the electric field driven inside. The frequency range of the experiment was from 10 MHz to 80 MHz where the standing waves are most likely to occur. © 2018 The Authors

Radiation patterns of antennas are among their most important characteristics. A popular method to obtain these consists in measurements inside anechoic chambers. However, in common engineering practice, small laboratories are usually equipped with only one shielded chamber. Such chambers are basically semi anechoic, providing a possibility of their modification to a fully anechoic version by placing appropriate absorbers on their reflective floor. Unfortunately, the systematic placement of absorbers on the floor of the chamber and their re-extraction increases the laboratory operating costs as it is time consuming and, moreover, there is a risk of mechanical wear or damage of the absorbers. Therefore, the authors of this paper decided to explore how great the impact of absorbers placed on the floor of the semi anechoic chamber is in case of measurement of radiation patterns of antennas operating at frequencies of 1 GHz and higher. Description of the experiment and its results are provided within the framework of this paper. © Published under licence by IOP Publishing Ltd.

The article presents a brief insight into the university research of efficient methods aimed at revealing counterfeit electronic components. Methods like multichannel curve tracing, component internal structure X-raying, system on chip optical inspection with higher magnification microscopy and Scanning Electron Microscopy combined with Element Energy Dispersive Spectroscopy (EDS) are powerful means for authenticity verification. Comparative analysis results serve as an illustration of cases where various features differences can warn not to let a particular component delivery penetrate the assembly process. © 2018 Institute of Physics Publishing. All rights reserved.

Electromagnetic interference has become a major problem for the design of electronic and electric devices, especially security device, where the great emphasis is placed on the reliability. Currently, the boxes of security device are mostly produced using plastic material. However, this material is not able to protect devices against electromagnetic interference, and this leads to efforts to find new ways and materials suitable for protecting the devices. In addition to the electromagnetic immunity requirements, the weight and ductility of the material must take into account. One of the variant how to protect equipment describes this paper focusing on the combination of a commercially available product and nano-layers of gold. The commercial product consists of rubber and ferrite. The advantage of this variant is material flexibility and relatively satisfying resistance to electromagnetic interference. The combining different types of materials can increase the electromagnetic immunity; however, it can lead to an increase in the weight of the final product or a worsening of the ability to model the material as needed. The fundamental structural element of the design was a commercial material combining rubber and ferrite, the structure of which the layer of gold was applied which is expensive but electrically conductive and presents an interesting aesthetic variation. The composite material was tested in the frequency range from 10 MHz up to 2 GHz which is the range corresponding to the European standards. The purpose of the paper is to determine the effect of the composite materials regarding electromagnetic immunity. © 2018 Electromagnetics Academy. All rights reserved.

In the last years, a large growth of radio-frequency electromagnetic interference was detected, especially in the frequency bands from 0.8 GHz up to 6 GHz. Tests of immunity of electrical devices must be carried out, because this type of interference can significantly affect their functionality. The aim of this paper is to explain the issue of electromagnetic susceptibility and describe the conditions of testing the immunity of electronic devices against the radio-frequency electromagnetic field according to the relevant electromagnetic compatibility standards. Also, sample electromagnetic immunity tests on the basic set of the intrusion and hold-up alarm system will be presented. © 2018, World Scientific and Engineering Academy and Society. All rights reserved.

Together with the rise of importance of devices employing wireless networks based on the principle of radio frequency data transfers, also the discussion on harmfulness of the electromagnetic radiation has occurred. The authors of this paper obviously cannot provide unambiguous answers to stop this discussion. On the other way, they can provide the reader of this paper with real data obtained by measurements processed inside a semi anechoic chamber that were performed at several wireless alarm peripherals. The measured values are compared to the technical and hygienic standards so the reader can form an idea of the amount of the radiated energy. Moreover, examples of waterfall diagrams of spectra generated by the devices are also listed in this paper. © 2018 De Gruyter Open Ltd. All Rights Reserved.

Immunity tests to radiated electromagnetic field are one of the most common tests performed within the framework of the electromagnetic compatibility. These tests are performed inside a shielded chamber provided the requirements given by the appropriate standards are kept. As the levels of the generated fields can be high and the output power of the transmitting amplifiers cannot be infinite, it is necessary to achieve a good performance of the transmitting antenna. By means of the real experiment the author of this paper shows how the height of the antenna placed above the conductive floor can affect the antenna’s voltage standing waves ratio and how this phenomenon affects the parameters of the whole measurement system. © Springer International Publishing AG 2018.

In recent years, electromagnetic interference has become a severe problem for electronic and electric devices design. That has led to an increase in demand for electromagnetic protection. However, there still exists a lot of devices sensitive to electromagnetic field effect, and one of them is security camera representing a crucial factor in the security area. The paper deals with the design of electromagnetically shielding grid for security cameras lenses. The basis of the experiment is the CST Microwave Studio simulation tool used to obtain the theoretical shielding effectiveness results which are subsequently verified by practical measurements using coaxial lines. © 2018 IEEE.

Class-D audio amplifiers seem to be a perspective way of development of electronics as they can obtain excellent power efficiency together with good performance characteristics. Moreover, they can be easily integrated on a single chip, resulting in clear, comprehensive and non-reckless construction of the audio amplifier. Because the power efficiency is considerably high, some designs even do not need any heat sink, since the heat dissipation can be fully provided by the chip package. In this paper a construction of such an amplifier, being based on the integrated circuit TPA3122, is described. This construction has been developed at Tomas Bata University in Zlin, using conventional component base. Moreover, the paper provides a comparison of the measured performance of the amplifier to the theoretical values provided by the manufacturer of the chip. © 2018, Danube Adria Association for Automation and Manufacturing, DAAAM. All rights reserved.

Electromagnetic interference has become a severe problem for electronic and electrical devices, especially for security cameras which are significantly sensitive to electromagnetic field effects. Therefore, there was born an idea to create shielding enclosure which protects these devices against the radiated field. This task was realized by the evolutionary algorithm included in the computational process of optimizing shielding effectiveness. © 2018 IEEE.

Together with the rise of importance of devices employing wireless networks based on the principle of radio frequency data transfers, also the discussion on harmfulness of the electromagnetic radiation has occurred. The authors of this paper obviously cannot provide unambiguous answers to stop this discussion. On the other way, they can provide the reader of this paper with real data obtained by measurements processed inside a semi anechoic chamber that were performed at several wireless alarm peripherals. The measured values are compared to the technical and hygienic standards so the reader can form an idea of the amount of the radiated energy. Moreover, examples of waterfall diagrams of spectra generated by the devices are also listed in this paper. © 2018 De Gruyter Open Ltd. All Rights Reserved.

The article presents a brief insight into the university research of efficient methods aimed at revealing counterfeit electronic components. Methods like multichannel curve tracing, component internal structure X-raying, system on chip optical inspection with higher magnification microscopy and Scanning Electron Microscopy combined with Element Energy Dispersive Spectroscopy (EDS) are powerful means for authenticity verification. Comparative analysis results serve as an illustration of cases where various features differences can warn not to let a particular component delivery penetrate the assembly process. © 2018 Institute of Physics Publishing. All rights reserved.

In order to deepen students' practical knowledge and understanding of the “Computer Networks” subject, a Monitoring Network System was developed that is able to read, collect and distribute data describing real technological processes. The Monitoring System design is based on Client/Server architecture. The model is represented by the real chemical reactor, which was created for the study of the enzymatic hydrolysis of potentially hazardous chrome-tanned wastes generated during leather manufacturing. Final system should be implemented at the university to the graduates and the system should be modular with possible communication support. The setup of the monitoring system comes with all needed explanation and procedures. © 2018, World Scientific and Engineering Academy and Society. All rights reserved.

Currently, shielding effectiveness represents a fundamental property of materials designed to resist electromagnetic fields effect. There are many materials suitable for shielding; however, the authors decided to use recyclable plastic materials whose surface was provided with gold or carbon nano-layer. The experiment aimed at determining the influence of conductive material nano-layers and application to commercially available security products.

This document provides real data obtained inside the semi anechoic room Frankonia SAC 3 plus that is certified for measurement of electromagnetic interferences and performing of electromagnetic susceptibility tests in the range from 30 MHz up to 18 GHz. The hereby presented data describe the response of the semi anechoic room to the electric field driven inside. The frequency range of the experiment was from 10 MHz to 80 MHz where the standing waves are most likely to occur. © 2018 The Authors

Immunity tests to radiated electromagnetic field are one of the most common tests performed within the framework of the electromagnetic compatibility. These tests are performed inside a shielded chamber provided the requirements given by the appropriate standards are kept. As the levels of the generated fields can be high and the output power of the transmitting amplifiers cannot be infinite, it is necessary to achieve a good performance of the transmitting antenna. By means of the real experiment the author of this paper shows how the height of the antenna placed above the conductive floor can affect the antenna’s voltage standing waves ratio and how this phenomenon affects the parameters of the whole measurement system. © Springer International Publishing AG 2018.

Electromagnetic interference has become a major problem for the design of electronic and electric devices, especially security device, where the great emphasis is placed on the reliability. Currently, the boxes of security device are mostly produced using plastic material. However, this material is not able to protect devices against electromagnetic interference, and this leads to efforts to find new ways and materials suitable for protecting the devices. In addition to the electromagnetic immunity requirements, the weight and ductility of the material must take into account. One of the variant how to protect equipment describes this paper focusing on the combination of a commercially available product and nano-layers of gold. The commercial product consists of rubber and ferrite. The advantage of this variant is material flexibility and relatively satisfying resistance to electromagnetic interference. The combining different types of materials can increase the electromagnetic immunity; however, it can lead to an increase in the weight of the final product or a worsening of the ability to model the material as needed. The fundamental structural element of the design was a commercial material combining rubber and ferrite, the structure of which the layer of gold was applied which is expensive but electrically conductive and presents an interesting aesthetic variation. The composite material was tested in the frequency range from 10 MHz up to 2 GHz which is the range corresponding to the European standards. The purpose of the paper is to determine the effect of the composite materials regarding electromagnetic immunity. © 2018 Electromagnetics Academy. All rights reserved.

In the last years, a large growth of radio-frequency electromagnetic interference was detected, especially in the frequency bands from 0.8 GHz up to 6 GHz. Tests of immunity of electrical devices must be carried out, because this type of interference can significantly affect their functionality. The aim of this paper is to explain the issue of electromagnetic susceptibility and describe the conditions of testing the immunity of electronic devices against the radio-frequency electromagnetic field according to the relevant electromagnetic compatibility standards. Also, sample electromagnetic immunity tests on the basic set of the intrusion and hold-up alarm system will be presented. © 2018, World Scientific and Engineering Academy and Society. All rights reserved.

Radiation patterns of antennas are among their most important characteristics. A popular method to obtain these consists in measurements inside anechoic chambers. However, in common engineering practice, small laboratories are usually equipped with only one shielded chamber. Such chambers are basically semi anechoic, providing a possibility of their modification to a fully anechoic version by placing appropriate absorbers on their reflective floor. Unfortunately, the systematic placement of absorbers on the floor of the chamber and their re-extraction increases the laboratory operating costs as it is time consuming and, moreover, there is a risk of mechanical wear or damage of the absorbers. Therefore, the authors of this paper decided to explore how great the impact of absorbers placed on the floor of the semi anechoic chamber is in case of measurement of radiation patterns of antennas operating at frequencies of 1 GHz and higher. Description of the experiment and its results are provided within the framework of this paper. © Published under licence by IOP Publishing Ltd.

Perception of image perceptions is one of the most important features of every person. With the help of our eyesight, we can perceive the world around us, acquiring information about our surroundings and recognize different objects in them. Thanks to the recipes of our eye, we can capture it clear information and transferred information to the brain where this information is further processed and evaluated. Based on that, we can recognize what we see.The detection of various objects or shapes in an image is a very important element of all operations involving Image Processing. It is not only used in the processing of Medical Imagery data, (e.g. searching for structures in tomographic images); but also, in the Security field, (e.g. access control); as well as in the human sector - i.e. in cameras and cameras, (e.g. face detection, smiles, etc.). This article deals with possible detection methods of objects in images.

High-speed cameras are expanding into science laboratories in many disciplines. For example, they can be used for monitoring of the impact testing course, widely spread in evaluation of materials. Usually, they exhibit a slight delay between the trigger pulse was applied and the recording was started. For many applications, this delay may be critical. The authors of this paper have faced two problems: The need to determine the delay in total and the need to check whether it varies in time or not. Therefore, the hereby described device was designed. It allows measurement of the delay of the camera's start in the range from 1 to 999 ms with the step of 0.1 ms. © 2017 IEEE.

As the importance of wireless networks based on radio frequencies increases in time, a space for discussion on harmfulness of the electromagnetic radiation has occurred. On the one hand there are studies showing that a direct influence of non-ionizing electromagnetic waves on the human organism was not confirmed until a certain intensity has been reached. On the other hand, critical voices appear, warning that even low intensities of non-ionizing electromagnetic fields are harmful to the human body, if it is exposed to the radiation for a prolonged time. The authors of this paper have no ambition to resolve this dispute. However, they provide data on the intensity of the electromagnetic fields generated by several components of electronic security system that are operating on the basis of the wireless network. The data have been gained in a specialized workplace and will allow the reader to imagine how intensive the radio signals generated by the battery-operated devices are compared to the current hygienic and technical limits. © The Authors, published by EDP Sciences, 2017.

Voltage-Amplifier stages are the basic components of commonly used high gain amplifiers the bias and other parameters of whose are set by the external negative feedback. The typical device that uses the voltage-Amplifier stage is the operational amplifier. Similar constructions can also be created on the basis of discrete transistors. From the circuit designer's point of view, the voltage-Amplifier stage defines the crucial parameters of the whole unit-the amplification factor, dominant pole of its transfer function and the slew rate. In this paper the proposal on construction of the voltage-Amplifier stage based on discrete transistors is described. When connected between the input differential amplifier and the output stage, it allows creating of cheap amplifier for HiFi applications with considerable performance. © The Authors, published by EDP Sciences, 2017.

As they are spread across almost all applications based on electrical circuits, frequency filters form one of the most complex issues on electronic devices. There exist a great number of different design methods based on various approaches. A large group of these filters is based on active components, namely amplifiers, that are equipped with the appropriate feedback to achieve the desired transfer function. In terms of applications operating at audible frequencies it became to be a rule that one or two operational amplifiers are applied, taking into consideration that their input impedance and amplification factor are infinitely high, whilst their output impedance is infinitely low. The simulation results presented in this paper show that these considerations may not be so strict. That means the input impedance may be in tens of kiloohms and the amplification factor of 40 dB without the feedback loop can do enough. Moreover, the operational amplifiers may be replaced by a simple circuit consisting of two transistors, as it is shown in this paper. This should be considered when calculating manufacturing costs of several designs. In this paper, a detailed description of a band pass filter for a third octave equalizer is presented. However, it is obvious, that the same approach can be applied in other designs. © ECMS Zita Zoltay Paprika, Péter Horák, Kata Váradi,Péter Tamás Zwierczyk, Ágnes Vidovics-Dancs, János Péter Rádics (Editors).

Algorithms - used for the identification and verification of individuals through fingerprint recognition technology have long been extensively used in Forensic Science and in the private sector. This work is concerned with the verification of the reliability of biometric systems that use fingerprints for their activities. Further, the eFinger programme is used to study similarities between men, women's and family members' fingerprints. © ECMS Zita Zoltay Paprika, Péter Horák, Kata Váradi,Péter Tamás Zwierczyk, Ágnes Vidovics-Dancs, János Péter Rádics (Editors).

Perception of image perceptions is one of the most important features of every person. With the help of our eyesight, we can perceive the world around us, acquiring information about our surroundings and recognize different objects in them. Thanks to the recipes of our eye, we can capture it clear information and transferred information to the brain where this information is further processed and evaluated. Based on that, we can recognize what we see.The detection of various objects or shapes in an image is a very important element of all operations involving Image Processing. It is not only used in the processing of Medical Imagery data, (e.g. searching for structures in tomographic images); but also, in the Security field, (e.g. access control); as well as in the human sector - i.e. in cameras and cameras, (e.g. face detection, smiles, etc.). This article deals with possible detection methods of objects in images.

As the importance of wireless networks based on radio frequencies increases in time, a space for discussion on harmfulness of the electromagnetic radiation has occurred. On the one hand there are studies showing that a direct influence of non-ionizing electromagnetic waves on the human organism was not confirmed until a certain intensity has been reached. On the other hand, critical voices appear, warning that even low intensities of non-ionizing electromagnetic fields are harmful to the human body, if it is exposed to the radiation for a prolonged time. The authors of this paper have no ambition to resolve this dispute. However, they provide data on the intensity of the electromagnetic fields generated by several components of electronic security system that are operating on the basis of the wireless network. The data have been gained in a specialized workplace and will allow the reader to imagine how intensive the radio signals generated by the battery-operated devices are compared to the current hygienic and technical limits. © The Authors, published by EDP Sciences, 2017.

As they are spread across almost all applications based on electrical circuits, frequency filters form one of the most complex issues on electronic devices. There exist a great number of different design methods based on various approaches. A large group of these filters is based on active components, namely amplifiers, that are equipped with the appropriate feedback to achieve the desired transfer function. In terms of applications operating at audible frequencies it became to be a rule that one or two operational amplifiers are applied, taking into consideration that their input impedance and amplification factor are infinitely high, whilst their output impedance is infinitely low. The simulation results presented in this paper show that these considerations may not be so strict. That means the input impedance may be in tens of kiloohms and the amplification factor of 40 dB without the feedback loop can do enough. Moreover, the operational amplifiers may be replaced by a simple circuit consisting of two transistors, as it is shown in this paper. This should be considered when calculating manufacturing costs of several designs. In this paper, a detailed description of a band pass filter for a third octave equalizer is presented. However, it is obvious, that the same approach can be applied in other designs. © ECMS Zita Zoltay Paprika, Péter Horák, Kata Váradi,Péter Tamás Zwierczyk, Ágnes Vidovics-Dancs, János Péter Rádics (Editors).

Algorithms - used for the identification and verification of individuals through fingerprint recognition technology have long been extensively used in Forensic Science and in the private sector. This work is concerned with the verification of the reliability of biometric systems that use fingerprints for their activities. Further, the eFinger programme is used to study similarities between men, women's and family members' fingerprints. © ECMS Zita Zoltay Paprika, Péter Horák, Kata Váradi,Péter Tamás Zwierczyk, Ágnes Vidovics-Dancs, János Péter Rádics (Editors).