1,721,011 research outputs found
Inclusiveness of Knowledge and Knowledge for Inclusiveness. Collaborative Digital Technology for Made in Italy. In: Martins N., Brandao D., "Advances in Design and Digital Communications", Proceedings of Digicom 2023, November 9-11 2023, Barcelos, Portugal
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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
Software defined networking applied to the heterogeneous infrastructure of Smart Grid
No full textThe increased need for power quality monitoring and active control of distribution grid necessitates the introduction of the Smart Grid (SG) approach, requiring an efficient ICT system for the monitoring and control of distribution grid state. The main obstacle to deployment of SG in real system is the lack of an efficient communication infrastructure. The use a heterogeneous network, which employs various technologies, appears to be the most promising solution. Nevertheless, the management of these communication systems has proven to be hard and error prone. In this paper, a Software Defined Networking (SDN) approach has been proposed to manage SG communication system applied to grid monitoring/supervision. The preliminary feasibility analysis is promising, although a more detailed modeling and analysis of the system is needed due to the extreme heterogeneity of the network
Harmonic Voltage Synchronization Using GPS Modules for Grid-Connected Power Converters
Full text linkVoltage-controlled inverters (VCI) for distributed energy resources allow operation in grid-connected and islanded conditions. Common techniques based on P-f, Q-V droop-control use sinusoidal voltage references for the VCIs, which brings unwanted circulating harmonic currents in case of connection to grids with distorted voltage. In fact, the voltages at the point of common coupling (PCC) of a sub-grid, like a microgrid, are typically distorted, and the related circulating currents pose potential issues in terms of distribution and converters losses, effectiveness of protections, and power quality. This paper proposes a strategy to synthesize, at the output of a VCI, the same harmonic voltage detected at the PCC to limit unnecessary harmonic current circulation. The proposed method uses global positioning system (GPS) modules to synchronize the harmonic voltage references of the VCIs with the PCC. To this end, low-bandwidth communication is exploited to broadcast the information to distributed VCIs. An experimental setup is implemented to test the proposed control using a hardware-in-the-loop approach for the modeling of the power stage. Several case studies are analyzed, showing the effectiveness of the proposed strategy in achieving power quality improvements: reduced load voltage harmonics, reduced circulating currents, reduced grid current harmonic content, and reduced power losses
Power-Based Control of Low-Voltage Microgrids
No full textThis paper presents a simple and robust control technique for distributed energy resources (DERs) in micro-grids. The technique utilizes the full potential of DERs during grid-connected and islanded operating modes. In grid-connected mode, the control pursues quasi-optimum operation of the microgrid so as to reduce the distribution losses and voltage deviations while fully exploiting renewable energy sources. In islanded mode, it effectively manages any available energy source, including storage devices, to ensure a safe and smooth autonomous operation of the microgrid. In addition, prompt adaptation to variations of the generated and absorbed power is ensured in each operating condition. The proposed control can be implemented by an Information and Communication Technology architecture, which is inherently flexible and scalable, allows plug-and-play integration of distributed energy sources, and does not involve time-critical communications
Circulating Harmonic Current Reduction in Distorted Voltage Conditions using GPS-based Synchronization
No full textVoltage-controlled inverters (VCI) for distributed energy resources allow operation in both grid-connected and islanded conditions. Common techniques based on P -f Q-V droop-control use sinusoidal voltage references for VCI, which brings to unwanted circulating harmonic currents in case of connection to grids with distorted voltage. In fact, the voltages at the point of common compiling (PCC) of a sub-grid, like a microgrid, are typically distorted and the resulting circulating currents pose potential issues in terms of additional distribution and converters losses, effectiveness of protections, and power quality. This paper proposes a strategy to synthesize, at the output of a VCI, the same voltage harmonics detected at the PCC. In this way, the related circulating harmonic currents are reduced. The proposed strategy uses global positioning system (GPS) modules to synchronize the harmonic voltage references of VCI with the PCC harmonic voltage. To this end, low-bandwidth communication is exploited to broadcast the required information to distributed VCI. Simulation and hardware-in-the-loop results show the effectiveness in reducing the circulating currents and also line impedance losses
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