Volume 13 (2020): Edition 1 (September 2020)

Parametric study and analysis of microstrip patch antenna with multiple slit positions is presented in this research contribution. This work is aimed to design a microstrip patch antenna, which can able resonate dual-band frequencies (i.e. 3.5 GHz and 5.3 GHz) with a trade-off between the geometrical parameters. The proposed antenna designed using the multiple slits on the patch, RT Duroid 5880 as substrate material, and with a defected ground structure. Owing to the geometrical miniaturization this antenna will be capable to work at sophisticated communication systems where size of the communication system is a desired parameter.

The paper presents a comparison of the two languages Python and R related to the classification tools and demonstrates the differences in their syntax and graphical output. It indicates the functionality of R and Python packages {dendextend} and scipy.cluster as effective tools for the dendrogram modelling by the algorithms of sorting and ranking datasets. R and Python programming languages have been tested on a sample dataset including marine geological measurements. The work aims to detect how bathymetric data change along the 25 bathymetric profiles digitized across the Mariana Trench. The methodology includes performed hierarchical cluster analysis with dendrograms and plotted clustermap with marginal dendrograms. The statistical libraries include Matplotlib, SciPy, NumPy, Pandas by Python and {dendextend}, {pvclust}, {magrittr} by R. The dendrograms were compared by the model-simulated clusters of the bathymetric ranges. The results show three distinct groups of the profiles sorted by the elevation ranges with maximal depths detected in a group of profiles 19-21. The dendrogram visualization in a cluster analysis demonstrates the effective representation of the data sorting, grouping and classifying by the machine learning algorithms. The programming codes presented in this study enable to sort a dataset in a similar research aimed to group data based on the similarity of attributes. Effective visualization by dendrograms is a useful modelling tool for the geospatial management where data ranking is required. Plotting dendrograms by R, comparing to Python, presented functional and sophisticated algorithms, refined design control and fine graphical data output. The interdisciplinary nature of this work consists in application of the coding algorithms for spatial data analysis.

The purpose of scientific research in this paper is to control the movement of solenoid actuators, by analyzing the applied signal. The actuator in a system is the execution element. The optimization of the system consists in finding new solutions for motion control for solenoid actuators, by designing and experimental realization of a static converter, also called alternating voltage inverter (VTA), which would become proposals for patents, or the realization of new experimental research stands. By analyzing the signal in this paper, it will be possible to design, experiment and test different types of VTA (with Arduino development boards, Raspberry Pi single board computers, logic gates) that will improve the reliability, future operation of thermal power plants.

The analysis technique of EEG signals is developing promptly with the evolution of Brain Computer- Interfaces science. The processing and classification algorithm of EEG signals includes three states: pre-processing, feature extraction and classification. The article discusses both conventional and recent processing techniques of EEG signals at the phases of preprocessing, feature extraction and classification. Finally, analyze popular research directions in the future.

The purpose of scientific research in this paper is to improve the operation of thermal power plants. The experimental stand for the study was made for testing, verifying and adjusting the dynamic parameters of the electromechanical actuators that are integrated in the gas valve component. In order to improve the performance of the thermal power plants by increasing the energetic, mechanical, electrical efficiency, this will be achieved through an alternating-alternative static converter, experimentally realizing the single-phase alternating voltage variable module. System optimization is to find new solutions for controlling the linear motion of electromechanical actuators, including the choice of working principles that would become patent proposals, or new research stands.