1,721,019 research outputs found
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
The Throughput Analysis of the DECT Access for Data Services
No full textThis paper investigates the ability of the DECT system to provide a cellular transmission service for data traffic composed of short messages. At first, the DECT performance is investigated in a single cell environment. Its access mechanism is analyzed in detail, discussing the overhead of the different procedures and measuring their quantitative effects. Then, the performance in the cellular environment specified by the ETSI is considered. The simulation results show a relatively small degradation in throughput, with respect to the single cell case, due to co-channel interferenc
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
CPRMA: the Centralized Packet Reservation Multiple Access for Local Wireless Communications
No full textPacket switched technology has been demonstrated attractive for use in cellular radio systems with short propagation delay, not only for data but also for voice. In fact, packet voice can efficiently exploit speech on-off activity to improve bandwidth use over TDMA. Such an approach has been first suggested by Goodman, Valenzuela, Gayliard and Ramaamurthi (1982), where packet reservation multiple access, an adaptation to the cellular environment of the reservation ALOHA protocol, has been introduced. However, R-ALOHA is based on a fixed frame scheme. For this reason, it cannot thoroughly exploit the natural advantages implied by the very short propagation delay encountered in microcellular systems, such as, for instance, the immediate retransmission of packets lost because of the interference noise from adjacent cells. We present the centralized PRMA, a natural enhancement of PRMA, that assigns to the base station a central role in scheduling the transmissions of terminals. As a consequence, packet retransmissions and the different delay constraints that emerge from voice and data integration, can easily be dealt with. We also propose a different reservation channel that avoids the bottleneck effect present in PRMA. Preliminary simulation results show a sensible gain, with respect to PRMA, in the maximum number of voice channels that can be accommodated and indicate the optimality of the approac
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