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Remote workshop for practical knowledge improvement in electrical engineering education: Computer control of electrical technology
No full textSimulation of Induction Traction Drive with Supercapacitor Energy Storage System Test Bench
No full textThis paper describes the application of supercapacitor energy storage system for induction traction drive test bench that replaces a real electric public transport for performing testing and researches. The suitability and usages of such bench for research circumstances are explained and the importance of the development of software mathematical model for performing simulations, which should be done before physical implementation measures, is reasoned. Also the working principle of the bench and applied components is described. A virtual model of the bench was built and simulations performed by using Matlab/Simulink software. The basic topology of the virtual bench model is described as well. The calculation part of this work shows the scaling of supercapacitor energy storage system by setting up different limits of working voltage range in order to adjust them to test bench parameters whereas the modelling part compares two simulation cases – the application of lesser supercapacitors and the application of more supercapacitors with the same common nominal voltage. Also autonomous mode simulations were performed. Simulation results are analyzed and recommendations for the application of the supercapacitor energy storage system, with respect to initial supercapacitor circuit voltage, are given
Simulation of Induction Traction Drive with Supercapacitor Energy Storage System Test Bench
No full textThe paper describes the application of supercapacitor energy storage system for induction traction drive test bench that replaces a real electric public transport for performing testing and researches. The suitability and usage of such bench for research purposes is explained and the importance of the development of software mathematical model for performing simulations to be done before physical implementation measures is reasoned. The working principle of the bench and applied components are described. A virtual model of the bench was built and simulations were performed using Matlab/Simulink software. The basic topology of the virtual bench model is described as well. The calculations of this work show the scaling of supercapacitor energy storage system by setting different limits of working voltage range in order to adjust them to test bench parameters, whereas the modelling compares two simulation cases – the application of less supercapacitors and the application of more supercapacitors with the same common rated voltage. The autonomous mode simulations were also performed. Simulation results are analyzed and recommendations for the application of the supercapacitor energy storage system, with respect to initial supercapacitor circuit voltage, are given
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Power Measurement and Data Logger Device with High-Resolution for Industrial DC-Grid Application
No full textAbstract – power and energy measurement and monitoring is a key leading factor for many industries in terms of energy and cost efficiency evaluation. Due to trends of Smart Grid concept application in industrial environment, including decentralized DC-Grid implementation, for precise evaluation - faster and lower cost measurement equipment is needed. Manufacturing industry use lot of industrial robots that have dynamic load characteristics, and to know their consumption faster measurement equipment is needed. This paper gives brief description of developed power measurement equipment, its structure and interconnection to industrial PROFInet network. Further as a testing method steady state and dynamic loads are selected and analyzed. For testing, specially created industrial DC-Grid testing environment and equipment has been used. Testing results shows that selected method and idea is working, and it is able to measure dynamic loads with high resolution. For other industrial load types, discussion rises, about how detailed resolution is needed in industrial SmartGrids, as energy forecast is a new trend in robotic industry, and manufacturing planning
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Smart City Street Lighting System Quality and Control Issues To Increase Energy Efficiency and Safety
No full textAccording to standards, the lighting system is one of the key elements to provide safety on city roads, defined by quality parameters. LED technology and movement detection sensor interaction bring about new regulation techniques, creating an energy-efficient smart LED lighting system concept. This paper reveals extensive comparative data analysis of Dialux simulation results before the project implementation phase and in-situ quality parameter measurements for various street profiles and LED luminary power types. After the project implementation phase, more than 1000 measurement points are reached. Further, energy efficiency increase issues in smart lighting systems are described in terms of LED luminary dimming profile analysis and future dynamic control application modes. The first findings clearly show that in most cases light output in simulation results is lower than in real situations; therefore, LED luminary power can be decreased, allowing for higher energy savings in first luminary maintenance years, keeping the same defined ME class or safety level. Let us suppose that the traffic intensity data are obtained from smart system sensors. In that case, the ME class can be dynamically selected during different night times, thus increasing safety and providing extra energy savings using the same system elements, as well as leading to better ROI values
Power Measurement and Data Logger with High-Resolution for Industrial DC-Grid Application
No full textPower and energy measurement and monitoring is a key factor for many industries in terms of energy and cost efficiency evaluation. Due to trends of Smart Grid concept application in industrial environment, including decentralized DC-Grid implementation, for precise evaluation – faster and low-cost measurement equipment is needed. Manufacturing industry widely uses industrial robots that have dynamic load characteristics for which faster measurement equipment is needed
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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