Elektronika ir Elektrotechnika https://eejournal.ktu.lt/index.php/elt <div><em>ELEKTRONIKA IR ELEKTROTECHNIKA</em> (ISSN 1392-1215) is a peer-reviewed open access bimonthly research journal of Kaunas University of Technology.</div> <p>The research journal <em>ELEKTRONIKA IR ELEKTROTECHNIKA</em> publishes original research papers on featuring practical developments that might have a significant impact in the field of <em>electronics and electrical engineering</em>, and focuses on automation, robotics &amp; control; automotive electronics; electric vehicles; electrical engineering; electronic measurements; electronics; high frequency technologies, microwaves; micro &amp; nano-electronics; power electronics; renewable energy; signal technologies; telecommunications engineering. It is aimed not only to researchers of certain field , but also to the wider public.</p> <p><strong><em>WoS</em></strong><strong><em>: </em></strong><em>Impact</em> <em>Factor</em><em> 0.707 (</em><em>2019); </em><em>5-Year </em><em>Impact</em> <em>Factor</em> <em>0.656 (</em><em>2019) </em><strong><em>Scopus</em></strong><strong><em>:</em></strong> <em>SCImago</em> <em>Journal</em> <em>Rank</em><em> 0.18 (2019)</em></p> Kaunas University of Technology en-US Elektronika ir Elektrotechnika 1392-1215 <p>The copyright for the paper in this journal is retained by the author(s) with the first publication right granted to the journal. The authors agree to the <a href="https://creativecommons.org/licenses/by/4.0/" target="_blank" rel="noopener">Creative Commons Attribution 4.0 (CC BY 4.0)</a> agreement under which the paper in the Journal is licensed.</p> <p>By virtue of their appearance in this open access journal, papers are free to use with proper attribution in educational and other non-commercial settings with an acknowledgement of the initial publication in the journal.</p> A Novel Procedure for Quick Design of Off-Grid PV Water Pumping Systems for Irrigation https://eejournal.ktu.lt/index.php/elt/article/view/28503 <p>It is known that meteorological variables from meteorological online services can be used for the design of photovoltaic (PV) water pumping systems for irrigation. The software LORENTZ COMPASS in such a manner uses as inputs solar irradiation, precipitation, and ambient temperature collected by the NASA Langley Research Centre over a period of more than 20 years. This paper proposes a novel procedure that uses the sunshine duration, precipitation, and ambient temperature as inputs. These inputs were collected by Weather Online UK during a period of 25 years. The effects of different data collection periods and data availabilities on the design of the PV water pumping system are also analysed and discussed. Along with the meteorological data, the proposed procedure uses as inputs datasheets from manufacturers of pumping systems and PV modules. The procedure is based on the Sivkov model that correlates the global horizontal irradiation with the sunshine duration and the elevation angle of the Sun. A case study, i.e., an existing PV water pumping system designed using LORENTZ COMPASS is used as reference for purposes of comparison and validation of the procedure. The results of the comparison showed a high level of accuracy, and a number of interesting conclusions are drawn from them.</p> Dardan Klimenta Julijana Lekic Sanela Arsic Dragan Tasic Nikola Krstic Dragana Radosavljevic Copyright (c) 2021 Dardan Klimenta, Julijana Lekic, Sanela Arsic, Dragan Tasic, Nikola Krstic, Dragana Radosavljevic 2021-04-29 2021-04-29 27 2 64 77 10.5755/j02.eie.28503 Editorial Board https://eejournal.ktu.lt/index.php/elt/article/view/28993 Elektronika ir Elektrotechnika Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-04-29 2021-04-29 27 2 2 3 Convolutional Neural Network and Fuzzy Logic-based Hybrid Melanoma Diagnosis System https://eejournal.ktu.lt/index.php/elt/article/view/28843 <p>Studies on the detection of early stage melanoma have recently gained significant interest. Computer aided diagnosis systems based on neural networks, machine learning, convolutional neural networks (CNNs), and deep learning help early stage detection considerably. The colour and shapes of the images created by the pixels are crucial for the CNNs, as the pixels and associated pictures are interrelated just as a person’s fingerprint is unique. By observing this relationship, the pixel values of each picture with its neighborhoods were determined by a fuzzy logic-based system and a unique fingerprint matrix named Fuzzy Correlation Map (FCov-Map) was produced. The fuzzy logic system has four inputs and one output. The advantage of CNNs trained with fuzzy covariance maps is to eliminate both the limited availability of medical grade training data and the need for extensive image preprocessing. The fuzzy logic output is fed to the pretrained AlexNet CNN algorithm. To deliver a reliable result, a deep CNN needs a large amount of data to process. However, to obtain and use the required sufficient data for diseases is not cost- and time-effective. Therefore, the suggested fuzzy logic-based fuzzy correlation map is tackling this issue to solve the limitedness of training CNN data set.</p> Fikret Yalcinkaya Ali Erbas Copyright (c) 2021 Fikret Yalcinkaya, Ali Erbas 2021-04-29 2021-04-29 27 2 55 63 10.5755/j02.eie.28843 Detection of EMG Signals by Neural Networks Using Autoregression and Wavelet Entropy for Bruxism Diagnosis https://eejournal.ktu.lt/index.php/elt/article/view/28838 <p>Bruxism is known as the rhythmical clenching of the lower jaw (mandibular) by the contraction of the masticatory muscles and parafunctional grinding of the teeth. It affects patients’ quality of life adversely due to tooth wear, pain, and fatigue in the jaw muscles. Recently, effective diagnosis methods that use electromyography, electrocardiography, and electroencephalography have been developed for bruxism. However, these methods are not economical since they require specialization and can be performed in clinical conditions. Although using surface electromyography signals alone is an economical solution, it is difficult to identify fatigue and parafunctional movements of the jaw muscles via electromyography signals due to peripheral effects. In this study, to achieve an accurate diagnosis of bruxism economically with only electromyography measurements, a new approach based on Autoregression and Shannon Entropies of Discrete Wavelet Transform Energy Spectra to identify jaw muscle activities and fatigue conditions is proposed. By using Artificial Neural Networks in the proposed model, bruxism activities can be detected most accurately.</p> Temel Sonmezocak Serkan Kurt Copyright (c) 2021 Temel Sonmezocak, Serkan Kurt 2021-04-29 2021-04-29 27 2 11 21 10.5755/j02.eie.28838 Programmability of Connectivity Control https://eejournal.ktu.lt/index.php/elt/article/view/28819 <p>Network programmability and edge computing as key features of next generation communications enable innovative services. While the programmability is focused on the core network of the fifth-generation system, the edge computing moves the network intelligence to the radio access network. This paper presents a study on the programmability of connectivity control as a function of radio access network using Multi-access Edge Computing. The capability of using more than one radio access technology simultaneously enhances reliability and increases the throughput, especially in dense networks. Opening the radio access network interfaces for programmability of multi-connectivity enables analytics applications to control the device connections to multiple radio links simultaneously based on information of radio conditions, user location or specific policies. The research novelty is in opening the radio access network interfaces for edge applications to access connectivity control.</p> Ivaylo I. Atanasov Evelina N. Pencheva Copyright (c) 2021 Ivaylo I. Atanasov, Evelina N. Pencheva 2021-04-29 2021-04-29 27 2 78 85 10.5755/j02.eie.28819 WISE: MQTT-based Protocol for IP Device Provisioning and Abstraction in IoT Solutions https://eejournal.ktu.lt/index.php/elt/article/view/28826 <p>Although numerous consumer devices use Transmission Control Protocol/Internet Protocol (TCP/IP) protocol stack to connect and communicate over the Internet, their integration into a single Internet of Things (IoT) solution represents a challenge, primarily due to the lack of the standardized interoperability framework on the application layer. Devices produced by different manufacturers cannot operate together out of the box, thus raising the cost of system setup and maintenance. In this paper, a novel protocol is proposed that aims to bridge this gap. It is based on Message Queuing Telemetry Transport (MQTT) protocol and allows the seamless integration of different kinds of IP devices into the connected system. The proposed protocol is complete as it covers the aspects of device discovery and association in the IoT network. It provides mechanisms for IoT network maintenance and defines the abstract device model and communication patterns to enable system-wide device interoperability. The other goal of the protocol is to be portable to resource-constrained platforms. To validate the proposed protocol, it was integrated into the existing smart home hub, and for testing and validation purposes, prototype devices were developed.</p> Istvan Papp Roman Pavlovic Marija Antic Copyright (c) 2021 Istvan Papp, Roman Pavlovic, Marija Antic 2021-04-29 2021-04-29 27 2 86 95 10.5755/j02.eie.28826 Dynamic FPAA-based Mixed-Signal Processing Circuit for Thin-Film CdTe/Lead-Free Perovskite Photodetectors https://eejournal.ktu.lt/index.php/elt/article/view/28751 <p>New photodetector structure combining thinned CdTe film with lead-free perovskite photoelectric film was produced and investigated. This setting of the CdTe thickness results in photodetector parameters’ competitiveness to the state-of-the-art in the field of advanced photoelectric materials. The device shows a promising sensitivity of ~40 μA/W, maximum responsivity of 10.6 mA/W at 460 nm, equal rise and fall times of 30 ms, and high linearity (maximum linearization error is less than 0.6 %). However, the optoelectronic performance of CdTe/lead-free perovskite structures integrated with signal processing circuit remains unexplored. For this purpose, Field Programmable Analogue Array (FPAA)-based mixed-signal processing circuit is developed for pulse width modulated electrical signal with duty cycle controlled by the illumination degree of the detecting photoelement. This novel approach guarantees a smooth change of the electrical output at a smooth change of the input illumination between the light and dark switching states and can be practically applied as a precise position detector of moving objects. The paper represents a synergistic connection between microelectronics, electronics, and signal technology.</p> Ivailo M. Pandiev Mariya P. Aleksandrova Copyright (c) 2021 Ivailo M. Pandiev, Mariya P. Aleksandrova 2021-04-29 2021-04-29 27 2 22 30 10.5755/j02.eie.28751 Analysis of Charge Pump Topologies for High Voltage Mobile Microphone Applications https://eejournal.ktu.lt/index.php/elt/article/view/28827 <p>This paper presents a novel analysis of charge pump topologies for very high voltage capacitive drive micro electro-mechanical system microphones. For the application, the size and power consumption are sought to be minimized, and a voltage gain of 36 is achieved from a 5 V supply. The analysis compares known charge pump topologies, taking into consideration on resistance of transistors and parasitic capacitances of transistors and capacitors in a 180 nm silicon-on-insulator process. The analysis finds that the Pelliconi charge pump topology is optimal for generating very high bias voltages for micro electro-mechanical system microphones from a low supply voltage when the power consumption and area are limited by the application.</p> Jakob K. Toft Ivan H. H. Jorgensen Copyright (c) 2021 Jakob K. Toft, Ivan H. H. Jorgensen 2021-04-29 2021-04-29 27 2 31 39 10.5755/j02.eie.28827 Design of a Wireless Charging System for e-Scooter https://eejournal.ktu.lt/index.php/elt/article/view/28837 <p>This article deals with the design and practical evaluation of a wireless charging system for e-scooters. As wireless charging undertakes popularity, initially, the state of the art within application area is realized. Consequently, due to variability of the configuration of the whole system, several alternatives are discussed considering the utilization of the power converter stages. High attention is given to the construction of the coupling elements and calculation of the main circuit components of the considered power converters. The experimental part of the paper is supported by the measurements of key properties, i.e., the operational characteristics of the whole converter system together with coupling coils. Here, the efficiency characteristics, together with the output power characteristics in dependency on the mutual distance between the transmitting and receiving coils, are evaluated. Received results represent an adequate design approach and practical use of the proposed Wireless Power Transfer (WPT) e-scooter charging configuration.</p> Jakub Skorvaga Michal Frivaldsky Miroslav Pavelek Copyright (c) 2021 Jakub Skorvaga, Michal Frivaldsky, Miroslav Pavelek 2021-04-29 2021-04-29 27 2 40 48 10.5755/j02.eie.28837 Reviewers https://eejournal.ktu.lt/index.php/elt/article/view/28994 Elektronika ir Elektrotechnika Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-04-29 2021-04-29 27 2 97 97 Title https://eejournal.ktu.lt/index.php/elt/article/view/28992 Elektronika ir Elektrotechnika Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-04-29 2021-04-29 27 2 1 1 Textile Antenna for First-Person View Goggles https://eejournal.ktu.lt/index.php/elt/article/view/28841 <p>Unmanned Aerial Vehicles, also known as drones, are vehicles controlled remotely. First-Person View (FPV) technology allows these vehicles to have greater versatility and be more easily piloted. The antennas currently used for video transmission are bulky and uncomfortable, so there is a need for this volume to be reduced to increase portability, being this the focus of the paper. The antenna was developed in textile materials to reduce its size and weight, as these materials allow for a better comfort and a reduced footprint. This paper presents a microstrip array adapted for the frequencies used in FPV video transmission. The designed textile antenna was compared with a commercially available rigid antenna used for this transmission. The comparison shows promising results for the antenna made of textile materials. The main goal of increasing the comfort and portability of the FPV goggles was achieved.</p> Luis Andre Pedro Pinho Carolina Gouveia Caroline Loss Copyright (c) 2021 Luis Andre, Pedro Pinho, Carolina Gouveia, Caroline Loss 2021-04-29 2021-04-29 27 2 49 54 10.5755/j02.eie.28841 Model Predictive Control of Nonlinear MIMO Systems Based on Adaptive Orthogonal Polynomial Networks https://eejournal.ktu.lt/index.php/elt/article/view/28780 <p>This paper considers a new design of model predictive control based on specific models in the form of adaptive orthogonal polynomial networks, built around a specially tailored basis of generalized orthogonal functions. Polynomial model has a single layer structure and a smaller number of model parameters than classical neural networks, usually used for model predictive control design, leading to lower complexity and shorter calculation time. Desired property of adaptability of the model is achieved by using additional variable factors inside the orthogonal basis. The designed controller was applied in control of twin-rotor aero-dynamic system as a representative of nonlinear multiple input-multiple output systems and compared to the other state-of-the-art control algorithms.</p> Marko T. Milojkovic Andjela D. Djordjevic Stanisa Lj. Peric Miroslav B. Milovanovic Zoran H. Peric Nikola B. Dankovic Copyright (c) 2021 Marko T. Milojkovic, Andjela D. Djordjevic, Stanisa Lj. Peric, Miroslav B. Milovanovic, Zoran H. Peric, Nikola B. Dankovic 2021-04-29 2021-04-29 27 2 4 10 10.5755/j02.eie.28780