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The paper aims to highlight some aspects regarding the cooling system of the 330 MW synchronous generators, used in the schemes of the technological flow of electricity production in high-power power plants. The 330 MW synchronous generators are characterized by the fact that they use direct cooling systems with water for the stator windings and hydrogen in the rotor windings with the mention that the cooling of the rotor windings is carried out in a closed circuit. [ABSTRACT FROM AUTHOR]

Educational accreditation guarantees the quality of the educational processes, products and services. Both the National Evaluation and Accreditation Agency (NEAA) in Bulgaria and Romanian Agency for Quality Assurance in Higher Education (ARACIS) in Romania are members of the European Association for Quality Assurance in Higher Education ENQA). They follow strict professional standards, methodologies, procedures, and criteria. It is common that the quality management systems in universities are based on ISO 9001. The specific standard for educational organizations such as universities and research institutes ISO 21001 is far less popular than ISO 9001. The purpose of this paper is to highlight opportunities for improvement of the internal quality management systems of educational organizations based on international standards. [ABSTRACT FROM AUTHOR]

The paper presents the study and analysis with finite elements of the hook of a hoist, as well as the load capacity of the hook varying the cross-sections. The selected sections were constant over time and then the sizes of two different sections were changed. The hoist hook is modelled using SOLIDWORKS software. Von Mises stress analyses were performed. To validate the stress distribution model for its correctness, he used the theory of curved beams. The obtained results were compared with those determined by analytical calculation and it was found that the deviations are at least 5%. The finite element analysis method can be used for different material types and different loadings. [ABSTRACT FROM AUTHOR]

The adoption of standards to ensure the quality of electricity delivered to medium and low voltage consumers was a desire of our country realized in 2004, with the ratification of the Association Agreement of Romania with the European Union, directive 89/336 EEC. The quality of the electricity distribution service to consumers connected to the electricity distribution networks is regulated by the Performance Standard approved by the National Energy Regulatory Authority (ANRE). In this sense, the paper aims to highlight the main parameters that characterize the quality of electricity supplied to consumers connected to the electricity distribution networks. [ABSTRACT FROM AUTHOR]

The paper presents the analysis and diagnosis of cables for data transmission in telecommunications. Among these data transmission cables, the paper presents the optical cable and the UTP cable. For these cables, following the analysis and diagnosis, the defects that appeared were fixed. At the same time, the services provided through the repaired cables were also checked. [ABSTRACT FROM AUTHOR]

The paper describes a numerical method that can be used to identify the number of fatigue cycles and the tests made to determinate the stress amplitude on the lever pin of a Kaplan turbine runner blade operating mechanism. For these purposes, were used measured data recorded for a period of two years, on the hydro units from a Romanian power plant. To process the fatigue cycles data obtained from measurements was used an algorithm specifically designed for this purpose. The number of fatigue cycles obtained by this method, can be used to analyze the fatigue lifetime of the lever pin from the runner blade operating mechanism. [ABSTRACT FROM AUTHOR]

The paper presents the modeling and simulation of the electromagnetic field in the insulation of medium voltage electric cables. The work also includes the mathematical and finite element model of the electromagnetic field for the medium voltage electric cable. This study presents how, with the help of the finite element method, an approximate solution, accepted in practice, can be obtained for a certain phenomenon defined by a series of specific differential equations. [ABSTRACT FROM AUTHOR]

The paper presents, based on the study and the experience of the authors in the field, some considerations, especially from an application aspect, useful in building a photovoltaic system for supplying electricity to an isolated apiary, as well as simulations for such a system, made with the PVGIS program . The main highperforming electric machines of today with relatively high energy consumption from an isolated beehive are identified, as well as their specific mode of use, during a calendar year, an essential factor for establishing the installed power of such a photovoltaic system and a its effective technical-economic design. [ABSTRACT FROM AUTHOR]

This paper presents the mathematical model and simulation of shielding gas flow in electric arc welding in a shielding gas environment, with the aim of determining the convective heat exchange coefficient by simulation. Electrical conduction analysis offers the possibility to determine current density and specific heat power distributions in regions of complex geometrical shape, which practically cannot be determined in any other way. The presented method allows to obtain material properties, and especially their temperature dependence, which cannot be determined directly, experimentally, such as those of the electric arc. [ABSTRACT FROM AUTHOR]

This paper proposes the conception, design and optimization of an individual exhaustion system for use in a welding laboratory. The verification of the system will consist of experiments to exhaust the fume emitted during manual welding with coated electrode, so that the fume emission reaches minimum values in order to obtain a performance function of the exhaust system. Optimisation of the method has resulted in the retention of 60% of the total dust emitted during welding, and attempts are being made by optimising the filter system or the position of the welder to make this percentage even higher. [ABSTRACT FROM AUTHOR]

Over operation time, there are a number of internal and external factors that change the characteristics of dielectric materials that are part of the electrical equipment. In areas with high pollution, an important requirement is the acidic chemical compounds in the soil in which the power cables are laid, which penetrate the insulation by infiltration, resulting in changes in the parameters of electrical insulation and causing a decrease in operating time. The paper is focused on the analysis, through a series of experimental determinations, of the effects of stresses to which the power cables laid in acidic environments are subjected, by simulating the operating conditions in the laboratory, obtaining concrete results. It also describes the direct current test installation used in the laboratory and presents the two stages of testing the cable sample inserted in the electrolyte, the first being a stage of accelerating the degradation of the insulation by supplying higher voltages to require insulation, and the second stage being the testing in the absence of the electric field, under the direct action of the chemical compounds from the installation tank. Given that in alternating current, the electric field causes an additional heating of the dielectric due to energy losses by electric polarization, the test is performed in direct current, precisely to be able to monitor the variation of insulation resistance in relation to temperature and losses through conduction currents, as a result of the Joule–Lenz effect and not as a result of the dielectric polarization process. At the same time, the power of the direct current source used is lower compared to that of an alternative current test source and does not contribute to the generation of electrical discharges during testing. [ABSTRACT FROM AUTHOR]

When it comes to road traffic, there are rules to follow and laws to respect that have the role of contributing to human safety. Ever since 1868, when the first traffic light was invented, traffic lights had the purpose of supporting the safety of people in traffic. Over time, traffic light systems have evolved in different directions, using increasingly advanced power supply, timing and control solutions. Most of the traffic light systems nowadays are oriented, from the point of view of technological development, towards streamlining road traffic, towards optimizing current consumption or towards the use of reliable components for operation in the external environment. In this paper, we propose a pedestrian-oriented traffic light system model. The idea is based on the fact that part of the road accidents that occur at pedestrian crossings with traffic lights are caused by the pedestrian who lives in the "century of speed". [ABSTRACT FROM AUTHOR]

The paper presents a study on the reception quality in Resita of the Radio Resita station, equipped with a Harris DX 10 type transmitter. Measurements were made regarding the reception quality, in the open air and semi-enclosed spaces, in several points in Resita considered representative using an appropriate device and two radio receivers of different classes. [ABSTRACT FROM AUTHOR]

The paper presents an automatic system for adjusting the speed of a direct current motor, the components of the automatic system as well as the implemented program. This elaborate automatic system has been tested for different temperatures at the system inlet. Following the realization and testing of the automatic system for adjusting the speed of a direct current motor, it was found that it comes into action because it is observed that when the temperature applied to the input increases and the speed increases, so the developed automatic system follows the prescribed values. This system can be successfully applied to cooling a car radiator, as high temperatures are encountered. This automatic system can also be implemented in other applications, both industrial and home, being easily adapted for dedicated uses. [ABSTRACT FROM AUTHOR]

The paper had as a reference element the major importance that synchronous generators with a unit power of 330 MW still have on the stability of the National Power System. It is well known that in the near future it is necessary to replace energy capacities based on burning coal with renewable sources. However, this objective is conditioned by a certain time horizon. Until the realization of these energy capacities, a continuous efficiency of the technological flow schemes that are included in the configuration of power plants is necessary. [ABSTRACT FROM AUTHOR]

In this work are analyzed the causes of failure of the electrical power cables laid in areas with high pollution level. The research was mainly aimed at identifying the effects of acidic water with sterile content on the insulation of electrical cables with low natural aging degree (recently pictured) and analyzing the results of the pH measurements of the water samples in the vicinity of the cable routes, harvested during the performance of the defectoscopy operations, in three different areas. The case presentation describes in detail the stages of prelocation and location of the fault at a medium voltage cable posed in the "Saint Helena" Wind Park in Coronin, jud. Caras-Severin, an area where the measured pH values recorded the highest acidity content in the soil water. The cable broke down as a result of the penetration of the polymeric insulation next to the shrinkable sleeve, caused by contact with acidic water containing sterile. [ABSTRACT FROM AUTHOR]

This paper present the algorithm for calculating the electric arc as a heat source in the arc welding processes, but also the dependence between it and the calorific value developed, because the quality of welded seams has a decisive influence in terms of reliability of welded structures. [ABSTRACT FROM AUTHOR]

The paper presents a solution for optimizing the electric arc welding process by modifying in small steps one of the parameters of the welding regime: the tension of the electric arc welding, for corner-welded joints. Accurate knowledge of the value range of a welding parameter leads to the avoidance of stress concentrators that may occur but also to defects in welded joints. [ABSTRACT FROM AUTHOR]

After a short presentation of the high voltage overhead power line Resita - Iaz, the paper studies the defects on this overhead power line, their causes, and how the line is protected from defects and how the defects were resolved. Finally, a solution is proposed to improve the protection against defects of the high voltage overhead power line Resita - Iaz, justifying the proposed solution. [ABSTRACT FROM AUTHOR]

The current paper presents a modal-based damage identification method that uses a one-layer neural network based on Bayesian regularization to estimate the location and severity of transverse cracks present in cantilever beams. A feedforward neural network is created, and it is trained by employing the relative frequency shift curves (RFS) for known damage positions and depths. The RFS values are plotted by using the squared modal curvature for the first eight weak-axis vibration modes and an enhanced method for assessing the severity for cracks of different depths. Training data were obtained for specific damage positions, by removing the transverse crack with a step of 10 mm along the cantilever beam. The ANN system is trained both to depict the location and severity of transverse cracks present in cantilever beams, and the results obtained are evaluated using data generated from FEM analysis. [ABSTRACT FROM AUTHOR]

This paper presents the comparison of the natural frequencies obtained for circular plates of different thicknesses and materials, with diverse boundary conditions. Modal analysis is performed by using the ANSYS simulation software. The results obtained in this study, have targeted the behavior of plates regarding the material, constraining methods and the eigenfrequencies in relation to the vibration modes. According to the results obtained from the modal analysis study, one can conclude that as the thickness of the steel plate decreases, its modal behavior is similar to that of a membrane. [ABSTRACT FROM AUTHOR]

We live in times where everything we do is on fast-forward, from our most simple to our most complex activity. More than that, we are all into multi-tasking thinking and doing, therefore a system that would ease all up would be more than welcome into our lives. With that in mind, we thought considering a system design that could be helpful with enjoying simple routines right in the comfort of our own homes, where we can escape this rush century. The system we implemented is a design, hardware and software, which can be adjusted, with required architectural changes, for a real home. For proposed design we used the "fashionable" IoT principles, electronic components and a software application. [ABSTRACT FROM AUTHOR]

This paper introduces device dedicated to the excitation of beam-like structures for damage detection issues. The vibration-based damage detection system consists of two subsystems, one used for actuation and the second for acquiring and processing the measured signal. The actuation is produced by an electromagnetic force induced by an induction coil controlled by a driver. The force can get a sinusoidal or a swept-sine evolution in the frequency range 1 to 1600 Hz. By controlling the individual vibration modes, we ensure a good signal-to-noise ratio, and, therefore, an accurate frequency estimation. The test procedure is presented in detail in this paper. It is verified by applying it to a cantilever beam with a constant cross-section in the absence and the presence of a small added mass. The small frequency changes are precisely identified. [ABSTRACT FROM AUTHOR]

The paper presents a series of aspects related to online engineering education in Romanian universities. Considering the existing material base as well as the level of knowledge and training of the participants in the online education: teachers, students, are presented ways of carrying out the teaching / course activity as well as the development of the applied activities (laboratory, seminar and project) both of the authors and of some colleagues. The issue of online examination will also be approached. Based on their own experiences but also following discussions with colleagues and students, the authors' conclusions on the advantages and disadvantages of this alternative learning system and its prospects for use as a permanent alternative method are presented. [ABSTRACT FROM AUTHOR]

We present a method to create representations that permit observing the frequency evolution in time, which is often necessary in industrial applications. The algorithm is implemented in the MS Excel and a generated signal with known parameters for observing the conformity between real and expected results is analyzed. The use of this algorithm is simple and it can be easily understood because limited data is involved. We also highlight how the signal is represented on the portions close to the moment in which the frequency change occurs. [ABSTRACT FROM AUTHOR]

Current software development directions open up a world of possibilities, especially in the engineering field. Present paper is meant to highlight the advantages and in particular the ease of using virtual instrumentation facilities, with a proper and adequate design and implementation of desired instrument. In this idea we bring into discussion a design for virtual instrument which can be used for data acquisition that can be stored for further simulations according to the needs required by the process in discussion. [ABSTRACT FROM AUTHOR]

The paper presents studies for increasing the autonomy of an electric bicycle by using a flexible / semi-flexible photovoltaic panel for charging the electric bicycle battery while it is stationary. [ABSTRACT FROM AUTHOR]

The paper presents a case study on the operating regime in charge of single-phase transformers. The case study relates to a functional model that has in its configuration a single-phase electric transformer with an apparent power of 250 VA and a transformation ratio of 230 / 27V. The monitoring of the electrical parameters in the load operation of the single-phase electric transformer was done by means of an electronic measuring block fed from an independent voltage source. [ABSTRACT FROM AUTHOR]

In the context of actual production, more and more adapted to the principles of Industry 4.0, the machines have to interact with other machines and with persons, and transmit in real time information that is processed and used to manage the production chains. The most important challenge is to make the machines working whit low or without human intervention. To this aim, it is necessary to find features that can be used for self-assessment of the machine condition and evaluation of the production processes in terms of finished and intermediate products. In this paper we present the strategy to acquire data from a CNC milling machine via a piezoelectric accelerometer and use this data to ensure the machine's autonomous functioning by involving an advanced algorithm. The machine condition and production evolution is transmitted to other machines and devices in order to take, also autonomous, decisions about their functioning. [ABSTRACT FROM AUTHOR]

The paper presents a qualitative comparative study between 3 of the main types of three-phase rectifiers ordered used in the supply of electromechanical and thermal consumers such as DC motors and DC electric arc. As the quality parameters, the critical control angle of the αcr rectifier and the switching angle γ were considered. [ABSTRACT FROM AUTHOR]

In the presented paper we tried to highlight the importance of the medium voltage electric cables in power transistors through electrical networks distribution to medium voltage consumers. Starting from consideration, the paper summarizes the prophylactic checks through which it is possible to monitor the evolution over time of the insulation condition of the power lines in the cable. [ABSTRACT FROM AUTHOR]

The paper aims at presenting how to coordinate intervention teams in the event of failure regimes in electric power distribution installations to domestic and industrial low voltage consumers. The work was theoretically and practically supported by an application implemented within the Faculty of Engineering and coordinated by the author. [ABSTRACT FROM AUTHOR]

The elaborate paper aimed studying the idling operating regime of an electrical transformer, single-phase, with apparent rating power of 250 VA, assembled on a working stand entering in the configuration of the Laboratory machines and electric drives within the Faculty of Engineering and Sustainable Development. [ABSTRACT FROM AUTHOR]

The paper proposes to carry out tests on the behavior of the turbine case with action arranged in the same tree line with the impeller of an electric generator with 330 MW power unit.The case study aims turbine operating after switching load with steam inlet only in medium pressure turbine body. [ABSTRACT FROM AUTHOR]

Given the fact that in the distribution process of electricity to final consumers, some situations arise where electricity can not be charged by distribution system operator due to objective reasons and it is required an estimate calculation in a fixed amount. The calculation of the recovery of the amount of electricity can be done according to some procedures developed by the operators of distribution and also approved by the competent authority. [ABSTRACT FROM AUTHOR]

In this paper we present a procedure for evaluating the isolation of the fixed coil wrapping for a hydro generator, by monitoring the level of partial discharges (PD). The evaluation is aiming to establish the maintenance work that is to be done, with the purpose of restoring the initial performance parameters of the hydro generator. By using this method we can highlight the status of the fixed coil wrapping of a hydro generator, this constituting a good warranty of a correct evaluation of the parameters for the isolation. [ABSTRACT FROM AUTHOR]

In this paper we present a procedure for evaluating the isolation of the fixed coil wrapping for a hydro generator, by monitoring the level of partial discharges (PD). The evaluation is aiming to establish the maintenance work that is to be done, with the purpose of restoring the initial performance parameters of the hydro generator. By using this method we can highlight the status of the fixed coil wrapping of a hydro generator, this constituting a good warranty of a correct evaluation of the parameters for the isolation. [ABSTRACT FROM AUTHOR]

The paper aims to conduct a case study on the influence of the supply voltage variation on the parameters of electric power cables of low voltage consumers . The argument which was the basis for the study, was the fact that the voltage variation is a parameter of quality of electricity supplied by the network operator and respecting the limits of its variation is regulated both by performance standards , and by the electricity supply contract between electricity suppliers and consumers, consumption per seat basis. [ABSTRACT FROM AUTHOR]

In this paper there is presented a study regarding the analysis of the dynamic behavior of column type structures with additional mass. By this analysis, we have followed the determining of the natural frequencies and modal shapes via the analytical computing and the simulating with the finite element method (FEM) in the ANSYS program. The results obtained regarding the computed natural frequencies are highlighted in tables and in graphics, whereas concerning the modal shapes for the 9 modes that were analytically and through FEM determined, these are drafted with the help of the MathCad, respectively ANSYS programs. [ABSTRACT FROM AUTHOR]