<abstract xmlns="http://www.w3.org/1999/xhtml">UAS (Unmanned Aerial Systems) are commonly used in 3D (dull, dirty and dangerous) missions, because these are not endangering the operators life, while reduce maintenance costs and increase maneuvering capabilities. Despite of these advantages we should consider the possible vulnerabilities of this technology as well. Unmanned vehicles can be controlled via direct communication link, or they can work in a preprogrammed mode. Usually the preprogrammed mode is based on radio navigation systems, so we can draw a conclusion that both depend on the RF environment. In this paper I analyze a possibility to effectively evaluate the communication link of an UAS. Developers have to consider several key factors (type of operation, endurance, payload type and size, propulsion, communication link, etc.) during the development process. They are also responsible that the final product meets the predefined requirements. On the other side commercial UAS owners should have a possibility to compare and evaluate the UAS before the acquisition. Finally, operators and frequency management entities need tools to diagnose the possible sources of interference regarding the unmanned vehicles. To understand the consequences of interference in the RF spectrum we have to be able to measure the quality of the communication link in different usage scenarios. In my research I evaluate the usage of SDRs (Software Defined Radios) in RF Test and Evaluation processes. After analyzing the possibilities for a flexible testbed, I demonstrate the usability with some measurements in the GNU Radio signal processing framework.</abstract>

GNU Radio Based Testbed (GRaTe-BED) for Evaluating the Communication Link of Unmanned Aerial Systems

<abstract xmlns="http://www.w3.org/1999/xhtml">This paper focuses on the hardware development of an indoor ultrasound based robot localization system. The problems related to the ultrasound based distance measurements are presented and solutions are proposed related to Time of Flight measurements and measurement synchronization. An optimization based compensation method is introduced to attenuate the effect of the ambient temperature on the distance measurement precision. Experimental measurements were performed to analyze the applicability of the developed system and measurement methods.</abstract>

Ultrasound-Based Indoor Robot Localization Using Ambient Temperature Compensation

<abstract xmlns="http://www.w3.org/1999/xhtml">The proliferation of sensor networks employing wireless data transmission technologies has paved the way for the collection of large amounts of measurement data. Several research teams have used this opportunity to develop algorithms aimed at gaining information from sensor data. Motion detection is one of the most actively researched areas. In this article, we present a system for examining motion detection in a general environment. In other words, motion forms are not identified with various wearable sensors; instead, we use the data collected by the sensors of mobile phones kept with almost all members of society now.</abstract>

Development of Motion Detection Algorithms Based on Simultaneous Execution Using Mobile Phone Sensors

<abstract xmlns="http://www.w3.org/1999/xhtml">This paper presents an evaluation of different methods used to deliver virtual machines capable of being accessed remotely by thin-clients. The objective of the research was to provide a recommendation for building a cost-effective computer infrastructure for use in two scenarios: as a programming lab, and as an office infrastructure.We have found that different thin-client solutions based on single board computers are reliable solutions for commercially available thin client replacement, because they can run free Linux-based operating systems, can handle Remote Desktop Protocol, have lower acquisition costs, lower power consumption and offer almost the same computing performance.For providing remote desktops, there are several methods and virtualization platforms available. We benchmarked some of these platforms in order to choose the one best-suited for implementation. Our conclusion is that Microsoft Remote Desktop Services outperforms the virtualization based solutions, but it entails high license fees. Of the virtualization solutions tested, the VMW are ESXi based one is the most reliable choice.</abstract>

Evaluation of Different Thin-Client Based Virtual Classroom Architectures

<abstract xmlns="http://www.w3.org/1999/xhtml">The presence of a second reactive gas in the magnetron sputtering chamber makes the process much more complicated, and the process control much more difficult than in the case of a single reactive gas. Macroscopic models have been developed in order to explain the complex phenomena and to provide support for the process control. These models are able to explain the nonlinearities of the process and the strong coupling between the control channels.This paper introduces a model created with the intention to of gaining a good grasp of the process, especially regarding the conditions necessary to obtain the required stoichiometry of the film deposited on the substrate. For this purpose, we modelled the formation of the desired ternary compound both directly from the available particle fluxes and from intermediary compounds. The surface of the substrate is divided into eight dynamically variable regions, covered by different compounds, each exposed to the streams of five types of particles.We present the analytical model and provide simulation results in order to demonstrate its capability toof describeing the nonlinear phenomena, which that characterisze the two-gas sputtering process.</abstract>

Department of Electrical Engineering, Faculty of Technical and Human Sciences

Sapientia Hungarian University of Transylvania

Department of Mechanical Engineering, Faculty of Technical and Human Sciences

Macroscopic Thin Film Deposition Model for the Two-Reactive-Gas Sputtering Process

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Volume 15 (2023): Issue 1 (December 2023)

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Volume 10 (2018): Issue 1 (December 2018)

Volume 9 (2017): Issue 1 (December 2017)

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Acta Universitatis Sapientiae, Electrical and Mechanical Engineering

 Series Acta Universitatis Sapientiae, Electrical and Mechanical Engineering surveys in various fields of Electrical and Mechanical Engineering. All papers are peer-reviewed. The language of the journal is English.  Why submit Strict review, open access, various fields covered.  Why subscribe and read Series Acta Universitatis Sapientiae, Electrical and Mechanical Engineering publishes only original papers and surveys in various fields of Electrical and Mechanical Engineering. All papers are peer reviewed. Rejection Rate   40%   Archiving  Sciendo archives the contents of this journal in Portico - digital long-term preservation service of scholarly books, journals and collections.  Plagiarism Policy  The editorial board is participating in a growing community of Similarity Check System's users in order to ensure that the content published is original and trustworthy. Similarity Check is a medium that allows for comprehensive manuscripts screening, aimed to eliminate plagiarism and provide a high standard and quality peer-review process. 