1,720,957 research outputs found

    Design Of The Overhead Line Section Of The Transmission System

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    This paper describes a basic summary about the transmission and distribution systems and their overhead lines in Czech Republic. In detail it also describes area around Ústí nad Labem which is very technically interesting for the design and the calculation of the overhead lines at voltage level of 400 kV. Therefore, the paper gives the proposals of the most suitable solution how to connect significant power energy source to the transmission system

    Potential of non-frequency ancillary services for a distribution system operator

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    This thesis provides a basic overview of the ancillary services in a transmission system. It summarizes changes regarding the implementation of European directives SOGL and EBGL. It describes in detail a portfolio of non-frequency ancillary services used in the distribution systems. It evaluates the demand of E.ON distribution system potential for those services in particular locations. Practical part is focused on a potential of reactive power management in this distribution area. It evaluates reactive power flow into transmission system and indicates the most critical substations. This thesis also covers analysis of existing resources in this distribution area and assign their possible potential in reactive power management

    Complex design of the overhead line section of the transmission system

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    The aim of thesis is a design of overhead lines of transmission system under specific weather conditions in given area. Furthermore, it gives a summary about the transmission and distribution systems and describes basics of overhead lines, used conductors and pylons in Czech Republic. It also presents the issue of climate conditions having a eminent influence on overhead lines. Moreover, theoretical part of thesis contains conductor mechanics and also mentions asymmetric state of overhead lines. Practical part deals with a design of specific part of overhead lines at voltage level of 400 kV and generally evaluates area where lines would be operated. In this area the new power energy source is hypothetically planned and therefore thesis analyzes possible variants of connection this source to transmission system. For one of these variants there are the calculations of two sections of the overhead lines under different weather conditions in more detail. The results bring longitudinal profile and assembling table for each section and they demonstrate the major impact of icing on the overhead lines

    Potential Of Non-Frequency Ancillary Services For A Distribution System Operator

    No full text
    This paper provides a basic overview of the ancillary services in a transmission system. It summarizes changes regarding the implementation of European directives SOGL and EBGL. It describes in detail a portfolio of non-frequency ancillary services used in the distribution systems. It evaluates the demand of E.ON distribution system potential for those services in particular locations. This paper also covers analysis of existing resources in the area of this distribution system

    Potential Of Non-Frequency Ancillary Services For A Distribution System Operator

    No full text
    This paper provides a basic overview of the ancillary services in a transmission system. It summarizes changes regarding the implementation of European directives SOGL and EBGL. It describes in detail a portfolio of non-frequency ancillary services used in the distribution systems. It evaluates the demand of E.ON distribution system potential for those services in particular locations. This paper also covers analysis of existing resources in the area of this distribution system

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

    Variations on the Author

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    “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

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We 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

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods
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