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    Thermal protection implementation of the contact overheadline based on bay controllers of electric transport traction substations in the mining industry
    (Sankt-Peterburg : Inst., 2021) Lantsev, Dmitry; Frolov, Vladimir; Zverev, Sergej; Uhrlandt, Dirk; Valenta, Jiří
    The article presents the principle of thermal protection of the contact overheadlineand substantiates the possibility of practical implementation of this principle for rail electric transport in the mining industry. The algorithm for the implementation of modern digital protection of the contact overhead line as one of the functions of the controller is described. A mathematical model of thermal protection is proposed, which follows from the solution of the heat balance equation. The model takes into account the coefficient of the electrical networktopology, as well as the coefficient of consumption of the current-carrying core of the cable, which determines the reduction in the conducting section from contact erosion and the growth of oxide films. Corrections for air flows are introduced when receiving data from an external anemometer, via telemechanics protocol. The mathematical model was tested by writing a real thermal protection program in the C programming language for the bay controller, based on the circuitry of which is the STM32F407IGT6 microcontroller for the microcontroller unit. Verification tests were carried out on a serial bay controller in 2020. The graphs for comparing the calculated and actual values of temperatures, with different flow rates of the current-carrying conductor of the DC cable, are given. To obtain data, telemechanics protocols IEC 60870-104 and Modbus TCP, PLC Segnetics SMH4 were used.
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    Open-Access-Finanzierung
    (Bielefeld : Transcript, 2020) Kändler, Ulrike
    Öffentlich finanzierte Forschungsergebnisse sollen schnell, weltweit und uneingeschränkt zur Verfügung stehen, das ist das erklärte Ziel von Open Access.2 Mit dem freien Zugang sowie dem Verzicht auf Verkauf und Abonnementgebühren entfällt aber auch eine traditionelle Möglichkeit, die Produktion von Zeitschriften oder Büchern zu finanzieren. Dennoch gibt es wissenschaftliche Publikationen keineswegs umsonst: Vom Betrieb des hochschuleigenen Dokumentenservers bis hin zu komplexen verlegerischen Infrastrukturen und Dienstleistungen – auch im Open Access entstehen mehr oder weniger hohe Kosten, die irgendwie getragen werden müssen. Wer zahlt also für den freien Austausch des Wissens?
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    Research Information Infrastructure in Ukraine: First steps towards building a national CRIS
    (Amsterdam [u.a.] : Elsevier, 2022) Kaliuzhna, Nataliia; Auhunas, Sabina
    Development and implementation of Current Research Information Systems (CRIS) is one of the most transparent and practical approaches to curate research information on a national level. The process of building and implementing such systems is a complex and time consuming where successful results heavily depend on the established research information infrastructure of a country, the interoperability of the systems and the quality of the information which reside in them. The purpose of this paper is to analyse the existing Ukrainian Research Information Infrastructure and identify which databases could be reused and integrated with a national Ukrainian Current Research Information System (URIS). The analysis showed that there are functional databases and registries that collect data on research activities and could be used as a data sources for the URIS. In particular, the Unified State Electronic Database on Education is a potential data source on higher educational institutions, the National Repository of Academic Texts - on metadata on research output, internal database of the National Research Foundation of Ukraine and database on research projects maintained by Ukrainian Institute of Scientific Technical and Economic Information - on projects. Secondly, it was identified that Ukrainian research infrastructure lacks complete, up-to-date registry on researchers. Finally, we discussed the challenges and solutions for further steps in building national CRIS.