1,720,973 research outputs found
Advanced operational functionalities for a low voltage Microgrid test site
No full textThis work aims to describe the implementation of a renewable energy based Microgrid test site facility at the University of Genova (Italy) and to depict the advanced functionalities there implemented within the national supported project Smartgen. The developed advanced Distribution
Management System (DMS) is based on a Supervisory Control And Data Acquisition (SCADA) system for the remote monitoring of a Low Voltage Microgrid composed by a photovoltaic (PV) plant, an ion-lithium energy storage system, electrical load and a weather station. The implemented DMS is embedded with advanced functionalities which provide 36 hours forecasting of the load consumption and renewable generation. The forecasted data are also used to optimally program and manage the storage device. The proposed algorithms are described and also implementation aspects are reported within the paper
Dynamic models for Distributed Energy Resources in a Microgrid environment
No full textSecurity assessment issues on modern power systems become more and more important also because of the growing penetration of DG (Distributed Generation) sources on the electric power systems. Today their penetration is still marginal with respect to the overall system load, but in the future they can cover a significant part of the consumptions, which means that research on power system security assessment has to investigate the possible impacts of such a phenomenon on security issues. Moreover, these models are essential for Microgrid studies and evaluation of their performances. In order to assess the actual impacts of DG sources on operational security it is necessary to have adequate dynamic models of the sources themselves. This paper presents the dynamic models of several renewable and fossil fuel based Distributed Energy Resources (DER) implemented in a well-known time domain simulator for power systems. Some simulation results are discussed
Pseudo-measurements modeling using neural network and Fourier decomposition for distribution state estimation
No full textThis work aims to propose a pseudo-measurement modeling method for Distribution State Estimation (DSE) application embedded in a Distribution Management System (DMS). The entire system is already installed on the distribution MV network of Sanremo, in the North of Italy, within the Smartgen research project. The acquisition architecture consists of a SCADA system, which allows the data exchange from meters installed in the MV-LV substations. In order to satisfy the system observability conditions and to perform the State Estimation (SE) algorithm, real-time measures need to be integrate with the pseudo-measures of the non-monitored substations. The paper investigates a load modeling technique, based on Artificial Neural Network (ANN) and Fourier decomposition, that allow the generation of pseudo-measurements starting from the historical database of the monitored substations
Linee guida per la pianificazione e la realizzazione di impianti fotovoltaici di rilievo
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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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