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> Reviewers https://eejournal.ktu.lt/index.php/elt/article/view/28549 Elektronika ir Elektrotechnika Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 85 85 Analysis of Non-Uniform Current Distribution in Multi-Fingered and Low-Voltage-Triggered LVTSCR https://eejournal.ktu.lt/index.php/elt/article/view/25352 <p>Laterally Diffused Metal Oxide Semiconductor Silicon-Controlled Rectifier (LDMOS-SCR) is usually used in Electrostatic Discharge (ESD) protection. LDMOS-SCR discharges current by parasitic SCR, but the MOS in it cannot work when parasitic SCR is stabilized. To further enhance the Electrostatic Discharge (ESD) discharging capability of LDMOS-SCR, a novel high failure current LDMOS-SCR with 12 V operation voltage is fabricated and verified in a 0.18-um high-voltage Bipolar-CMOS-DMOS (BCD) process. Compared with conventional LDMOS-SCR, the novel LDMOS-SCR (LDMOS-SCR-R) introduced a heavily doped p-type region, which is located between the heavily doped n-type and p-type regions of Cathode and is connected with the gate. The adding p-well resistance can drop the voltage on the gate, and the gate with p-well resistance also has resistance and capacitance coupling effect. According to the results of the transmission line pulse test (TLP), the voltage applied to the gate by increasing the p-well resistance plays a major role in the device working mechanism. Under the same device size, LDMOS-SCR-R has higher <em>I<sub>t2</sub></em> (8.6 A) than conventional LDMOS (2.21 A) or LDMOS-SCR (6.62 A) in TLP results. Compared with LDMOS-SCR, the failure current of LDMOS-SCR-R increases by 30 %, and the FOM of LDMOS-SCR-R increases by 34 %. The response of LDMOS-SCR-R is also faster than that of LDMOS-SCR under larger current conditions. In addition, the phenomenon in TLP results is consistent with simulation results. The proposed LDMOS-SCR-R can effectively increase failure current without affecting the device’s design window, and the additional p-type region will not increase the layout area.</p> Zijie Zhou Xiangliang Jin Yang Wang Peng Dong Yan Peng Jun Luo Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 41 47 10.5755/j02.eie.25352 Editorial Board https://eejournal.ktu.lt/index.php/elt/article/view/28544 Elektronika ir Elektrotechnika Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 2 3 IoT-based Dairy Supply Chain - An Ontological Approach https://eejournal.ktu.lt/index.php/elt/article/view/27612 <p>Emerging digital transformation in industry is noticeable among others in Supply Chain Management (SCM). For instance, applying new-generation digitalized technologies in the Dairy Supply Chain (DSC) enables an increase of manufacturing productivity, improves planning and forecasting, and also enhances competitive capabilities according to Industry 4.0 assumptions. It is worth mentioning, that in modern DSC, high visibility of raw materials, components, products, and processes by all contributors on all stages of DSC is crucial. This article focuses on the transparency aspect of the DSC supported by IoT-based technologies enabling interoperability among all DSC participants. The paper addresses the problem of effective integration of heterogeneous data sources, i.e., deployed new technological IoT solutions with traditional SCM systems and a third-party software component. The main objective of this report is to propose the IoT-based DSC model comprising four chain stages: milk production, milk transportation, milk processing, and dairy products distribution. Moreover, the comprehensive DSC domain ontology as a knowledge model is formulated and described. The ontology aims on improvement of the DSC management efficiency by facilitating interoperability within DSC. The applicability of the proposed ontological model is verified using a sustainable-oriented case study, which estimates the environmental footprint at the milk transportation stage of the DSC.</p> Bartosz Jachimczyk Rafal Tkaczyk Tomasz Piotrowski Sven Johansson Wlodek Kulesza Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 71 83 10.5755/j02.eie.27612 Analysis, Design, and Actual Fabrication of a Hybrid Microstrip-SIW Bandpass Filter Based on Cascaded Hardware Integration at X-Band https://eejournal.ktu.lt/index.php/elt/article/view/27479 <p>In this paper, the Microstrip-Substrate Integrated Waveguide (M-SIW) bandpass filter is designed, simulated, and fabricated based on the theoretical analysis. The Substrate Integrated Waveguide (SIW) highpass filter and the microstrip lowpass filter are combined in a hybrid design to achieve the M-SIW bandpass filter in the X-band. This design is more comprehensible and easier to achieve a bandpass filter at a desired frequency. The SIW highpass filter and the microstrip lowpass filter are connected in series to achieve the bandpass filter. To the measured results of the fabricated M-SIW bandpass filter, the center frequency is 10.20 GHz and the bandwidth is 2.40 GHz. When the analytical and measurement results are compared, the frequency change in the cut-off frequency is 6.02 % and the frequency change in the bandwidth is 8.74 %. It is generally seen that analytical, simulation, and measurement results are compatible with each other. The M-SIW bandpass filter can be broadly used in radar, Worldwide Interoperability for Microwave Access (WiMAX), and satellite technologies. The filters are simulated in Computer Simulation Technology (CST) Studio Suite.</p> Kemal Guvenli Sibel Yenikaya Mustafa Secmen Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 23 28 10.5755/j02.eie.27479 Design and Manufacture of a Multiband Rectangular Spiral-Shaped Microstrip Antenna Using EM-Driven and Machine Learning https://eejournal.ktu.lt/index.php/elt/article/view/27583 <p>This paper presents a multiband rectangular microstrip antenna using spiral-shaped configurations. The antenna has been designed by combining two configurations of microstrip and spiral with consideration of careful selection of the substrate material, the dimension of the rectangular microstrip, the distance between the turned spiral, and the number of turns of the spiral. The efficiency and accuracy have been improved using machine learning algorithms as well. Machine learning has been studied to model the proposed antenna based on the performance requirements, which requires a sufficient training data to improve the accuracy. Three different machine learning models are applied to improve the accuracy and generalization performance and compared to simulation and measurement results. Simulation, measurement, and machine learning results confirm that the proposed antenna is a new electrically small and operating over a wide range of high-frequency bands between 1 GHz–4 GHz. Machine learning models have the best prediction ability with a mean square error (MSE) of 0.03, and 0.05. The antenna structure and size are compatible and suitable for several multi-band wireless mobile systems operating in L-band and S-band. The results, such as directivity, Half-Power Beamwidth, Voltage Standing Wave Ratio (VSWR), and S-parameter curves, are analysed and compared with the numerical formulation for both spiral and microstrip antennas.</p> Ashrf Aoad Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 29 40 10.5755/j02.eie.27583 Non-Linear Load Characterisation Using Orthogonal Apparent Power Decompositions https://eejournal.ktu.lt/index.php/elt/article/view/25861 <p>There is no generally accepted definition for apparent power components in circuits with non-sinusoidal conditions. The decomposition of apparent power has been the subject of many discussions and is still an open topic. Over the years, a number of apparent power decompositions have been proposed and analysed, usually in the context of compensation. These analyses were performed by means of simulations or by calculating quantities using measurements on a simple test circuit. Here, we present a unique system capable of simultaneous apparent power decompositions for non-sinusoidal conditions in real-time. The system can calculate power components related to various power decompositions. The system’s capabilities are demonstrated on non-linear load characterization.</p> Marko A. Dimitrijevic Dejan Stevanovic Vanco B. Litovski Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 12 22 10.5755/j02.eie.25861 Title https://eejournal.ktu.lt/index.php/elt/article/view/28543 Elektronika ir Elektrotechnika Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 1 1 Deep Learning Framework with ECG Feature-Based Kernels for Heart Disease Classification https://eejournal.ktu.lt/index.php/elt/article/view/27642 <p>Heart disease classification with high accuracy can support the physician’s correct decision on patients. This paper proposes a kernel size calculation based on P, Q, R, and S waves of one heartbeat to enhance classification accuracy in a deep learning framework. In addition, Electrocardiogram (ECG) signals were filtered using wavelet transform with dmey wavelet, in which the shape of the dmey is closed to that of one heartbeat. With this selected dmey, each heartbeat was standardized with 300 samples for calculation of kernel sizes so that it contains most features in each heartbeat. Therefore, in this research, with 103,459 heart rhythms from the MIT-BIH Arrhythmia Database, the proposed approach for calculation of kernel sizes is effective with seven convolutional layers and other fully connected layers in a Deep Neural Network (DNN). In particular, with five types of heart disease, the result of the high classification accuracy is about 99.4 %. It means that the proposed kernel size calculation in the convolutional layers can achieve good classification performance and it may be developed for classifying different types of disease.</p> Thanh-Nghia Nguyen Thanh-Hai Nguyen Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 48 59 10.5755/j02.eie.27642 A Novel Fitting Model for Practical AIS Abnormal Data Repair in Inland River https://eejournal.ktu.lt/index.php/elt/article/view/27661 <p>Affected by the environment of inland waterway, an Automatic Identification System (AIS) collects lots of abnormal data, which significantly reduces the inland river navigation performance using AIS data. To this end, this paper aims to restore the AIS data by repairing the lost data points. By analysing enormous abnormal AIS data, the abnormal data were firstly divided into three types, i.e., the erroneous data, short-time lost data, and long-time lost data. Then, a cubic spline interpolation method was employed to deal with the erroneous data and short-time lost data. Meanwhile, a least square support vector machine method was utilized to repair the long-time lost data. Finally, field experiments were carried out to validate the applicability of the proposed method, and it is shown that the fitting model can repair the AIS data with an accuracy of more than 90 %.</p> Wei He Xinlong Liu Xiumin Chu Zhiyuan Wang Pawel Fracz Zhixiong Li Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 60 70 10.5755/j02.eie.27661 Optimization of VFD Operations for Transporting Equipment of Packages https://eejournal.ktu.lt/index.php/elt/article/view/26584 <p>This study is focused on the efficiency of automated transferring system of packages equipped by variable-frequency drive (VFD) and servo drive motor. It was found that rotation frequency of induction motors and linear speed of servo drive decisively affected the unit efficiency that operates in the periodic mode. The system duty cycle was divided in two separate parts taking into account time spans needed to complete the specific tasks by each separate equipment of the system. In order to reduce the power usage of the system, the duration of each part of cycle was extended. Lowered electricity consumption leads to the extension of each cycle’s stage operating times. Frequencies of motors and linear speed of servo drive motors were optimized depending on cycle stages duration. Optimized frequency and linear speed values were calculated and loaded into motors controllers, and the efficiency of each separate equipment was measured, as well as total efficiency of the system. Experimental system debugging using optimized parameters proved that system efficiency increases up to 60 %, and that is closely matched with calculated values.</p> Lione Urmoniene Jelena Dikun Jolanta Januteniene Copyright (c) 2021 Elektronika ir Elektrotechnika 2021-02-25 2021-02-25 27 1 4 11 10.5755/j02.eie.26584