<abstract xmlns="http://www.w3.org/1999/xhtml">

Several precision technologies require video measuring systems that perform fast an extensive number of routine measurements and deliver high accuracy outcome. The quality of achievement is intrinsically determined by the measurement technique where with the applications that operate these systems are designed. The paper advances a simplified and at the same time comprehensive approach, proposing a new video distance measuring method using a single camera. It is designed to assess the distance at which the visual task is from the camera, using three adjacent focus positions. Practically, the method involves two stages: calibration and measurement. Calibration is realized only once for each camera type and involves setting the measuring range for all positions of the focus lens where maximum clarity is obtained. Distance measurement involves the use of the maximum sharpness position of the lens and the correlation with the sharpness values of the positions next to the maximum sharpness position.
</abstract>

Video Distance Measurement Method Based on Three Focus Positions

<abstract xmlns="http://www.w3.org/1999/xhtml">

Measurement and control systems in maritime engineering applications are quite similar to those in shore based engineering applications except for some unique features which differentiate between each of them. These features are either related to the specific nature and purpose of the maritime application (Various types of commercial ships, oil/gas rigs and others) or linked to the harsh environmental conditions such as salinity, corrosion and vibration which usually exist in higher levels than shore based applications. Accordingly and due to such a specific nature of maritime engineering applications, more requirements should be considered to ensure reliability and stability for measurement and control process avoiding any negative effects that might be associated with such a unique engineering environment. As was discussed in (Abotaleb, 2021), smart transmitters based on hybrid analogue-digital (HART) and digital (Foundation Fieldbus and Profibus PA) communication protocols with additional diagnostic information, they might be a possible wired alternative for analogue transmitters (mostly based on 4-20 mA analogue standard). Similarly, wireless HART protocol can be an alternative for 4-20 mA analogue transmitters. This article will discuss the possibility of replacing classical 4-20 mA analogue transmitters with wireless HART smart transmitters on commercial ships as an example for maritime engineering application. The first section of the discussion will include a theoretical background for the basic principles of wireless HART protocol among other wireless technologies used in industrial automation. The second section of the article will discuss the possibility of utilising wireless HART protocol in the most common measurement and control systems on any commercial ship in order to discover the degree to which wireless HART can be fully or partially integrated with maritime engineering applications. Afterwards, better realization for such a concept will be rendered by an analytical planning case study conducted for tank level measurement system on different types of commercial ships. Based on both the theoretical and the analytical sections, the experimental section will manifest the importance of some of the necessary key elements to implement a reliable wireless HART network. These key elements are RSSI levels, supply voltage stability and the capability of wireless HART adapters to integrate between wired HART protocol and wireless HART network.
</abstract>

Towards Reliability and Safety Improvement of Measurement and Control Processes on Ships: Implementation of Wireless Hart Protocol

<abstract xmlns="http://www.w3.org/1999/xhtml">

Practical applications in electrical engineering often deal with analog signals, but there are employed also digital circuits and microcontrollers. Sometimes it is easier or cheaper to improvise DA and AD converters instead of using dedicated ones. This paper is a comparative analysis of how accurate the analog signals can be generated from digital systems, like Field Programmable Gate Arrays (FPGAs) using only additional passive circuits. For this analysis, different FPGAs families were tested. Two alternatives of generating analog signals were considered in this study: PWM and R2R network. The analysis has been performed for a common frequency band, from 100 Hz to 30 kHz, using a virtual instrument for building an automated test system. At 10 kHz the PWM module obtains better THD values, reaching even 0.013% and at 30 kHz the R2R module obtains better THD values, reaching even 0.222%.
</abstract>

Distortion Analysis for Programmable Analog Signals Generated Using FPGA

<abstract xmlns="http://www.w3.org/1999/xhtml">

Polymers are materials widely used in many important technologies and applications because of their optical, physical, mechanical, thermal and chemical properties. Polyethylene terephthalate (PET) foil is often used as an insulating material in printed electronics, flexible circuitry, displays, industrial applications, graphic films, or for clinical and healthcare applications. A big inconvenience of PET film is the low surface tension which also implies a low wettability, resulting in poor coating adhesion and poor printing properties. In order to eliminate this disadvantage, a surface treatment was used by means of a dielectric barrier discharge (DBD) operating in ambient air at atmospheric pressure which consisted of a high voltage AC source and two circular metal electrodes 60 mm in diameter. The paper aims are to treat two different PET film substrates designed in this work as PET 1, without thermal treatment, and PET 2 which is heat stabilized. The effect of plasma exposure was assessed by determining the water contact angle by means of an Ossila goniometer and by measuring the surface tension with a special ink. The considered foils were exposed to different DBD treatment times (0.2, 0.5, 1, 5, 10, 30 s) and the evolution of the water contact angle overtime after treatment up to 96 hours was monitored. It was found that the water contact angle of the untreated PET 1 and PET 2 was 74° and 73.5°, respectively, and after 30 s DBD treatment time it decreased to 30.9° and 30°, respectively.
</abstract>

DBD System Operating in Ambient Air for Surface Treatment of Polyethylene Terephthalate Films

<abstract xmlns="http://www.w3.org/1999/xhtml">

Nonlinear systems exhibit complex dynamic behaviour, including quasi-periodic and chaotic. The present contribution presents a composed analogue and discrete-time structure, based on second-order nonlinear building blocks with periodic oscillatory behaviour, that can be used for complex signal generation. The chosen feedback connection of the two modules aims at obtaining a more complex nonlinear dynamic behaviour than that of the building blocks. Performing a parameter scan, it is highlighted that the resulting nonlinear system has a quasi-periodic behaviour for large ranges of parameter values. The nonlinear system attractor projections are obtained by simulation and statistical numerical results are presented, both confirming the possible use of the designed system as a noise generator.
</abstract>

“Gheorghe Asachi” Technical University of Iaşi

“Grigore T. Popa” University of Medicine and Pharmacy of Iaşi

Connecting Analog and Discrete Nonlinear Systems for Noise Generation

<abstract xmlns="http://www.w3.org/1999/xhtml">

The new requirements for point-of-load converters include the dynamic behavior, leading to the need for improvements in the control system for the conventional buck converter. Usually, the regulator design, in order to secure stability at parameter or mode variation, aims a zero steady-state error and a phase margin over 60 degrees. The design based on Venable’s K-factor method (Venable, 1983) helps achieve this topic. A more modern control design method based on State Space is used progressively on digital platforms. This paper extends the merits of the State Space based design procedure with an analogous mode implementation.
</abstract>

Analogous Mode Implementation of State Space Based Control of Buck Converter

AHEAD OF PRINT

Volume 68 (2022): Issue 4 (December 2022)

Volume 68 (2022): Issue 3 (September 2022)

Bulletin of the Polytechnic Institute of Iași. Electrical Engineering, Power Engineering, Electronics Section

Volume 67 (2021): Issue 4 (December 2021)

Volume 67 (2021): Issue 3 (September 2021)

Volume 67 (2021): Issue 2 (June 2021)

Volume 67 (2021): Issue 1 (March 2021)

 The journal Buletinul Institutului Politehnic din Iaşi, Electrotehnicã. Energeticã. Electronicã (Bulletin of thE Polytechnic Institute of Iasi, Electrical Engineering, Power Engineering, Electronics section) is publishing papers that present the research work in the broad area of Electrical Engineering, Power Engineering, Electronics, Automatic Control and Computer Science. The proposed topics of the published papers cover not only classical fields of Electrical and Computer Engineering Science, but also subjects in areas that show a rapid process of maturation. The journal is an effective mean of disseminating the recently obtained results, of promoting interdisciplinary research and also an opportunity for young researchers to present their relevant scientific work.  Authors are invited to submit papers to one of the following subject areas: Electrical Engineering Power Engineering Electronics Automatic Control Computer Science  The journal Buletinul Institutului Politehnic din Iaşi, Electrotehnicã. Energeticã. Electronicã is publishing mainly original research but, good quality focused review articles that scrutinize state of art, that highlight newly emerging trends or propose future directions for developing areas, are also welcomed after consulting the editor.  All articles are subject to a blind review assessing the content, scientific relevance, novelty and originality of research, quality of presentation, text structure and style, referencing, and the overall contribution of the article. Based on the review, the editor reserves the right to reject the paper or request the author to adjust it according to the reviewers suggestions.  The journal Buletinul Institutului Politehnic din Iaşi, Electrotehnicã. Energeticã. Electronicã is jointly coordinated by the Faculty of Electrical Engineering, Faculty of Electronics, Telecommunications and Information Technology and Faculty of Automatic Control and Computer Engineering of “Gheorghe Asachi” Technical University of Iași.  Plagiarism and Archiving Policy  Archiving  Sciendo archives the contents of this journal in System's 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. 

Bulletin of the Polytechnic Institute of Iași. Electrical Engineering, Power Engineering, Electronics Section

Bulletin of the Polytechnic Institute of Iași. Electrical Engineering, Power Engineering, Electronics Section

Video Distance Measurement Method Based on Three Focus Positions

Towards Reliability and Safety Improvement of Measurement and Control Processes on Ships: Implementation of Wireless Hart Protocol

Distortion Analysis for Programmable Analog Signals Generated Using FPGA

DBD System Operating in Ambient Air for Surface Treatment of Polyethylene Terephthalate Films

Connecting Analog and Discrete Nonlinear Systems for Noise Generation

Analogous Mode Implementation of State Space Based Control of Buck Converter

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