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A comprehensive study on light signals of opportunity for subdecimetre unmodulated visible light positioning
No full textReceived signal strength visible light positioning-based precision drone landing system
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An on-body antenna for control of a wireless prosthesis in the 2.45 GHz industrial scientific and medical frequency band
No full textElectronic prostheses require a communication link to other on-body nodes, for example, for control signal extraction. This link can be made wireless to improve user experience compared to wired solutions. Even though ample on-body communication techniques have been described for wireless body area networks, in prosthetics, the efficiency of wireless links is often neglected, in particular when radio frequency (RF) antennas are used. This work aims to show the benefit of on-body RF antenna design for prosthetics, by developing a dedicated antenna for use in a lower arm prosthesis. Additionally, this work tries to fill a gap in literature, where some antennas for dedicated on-body RF communication are presented, but no antennas specific for communication along the arm exist. To this aim, numerical simulations are performed using a cylindrically layered arm model to design a novel, electrically small, capacitively loaded, meandered, 2.45 GHz monopole antenna. The antenna is fabricated using 3D printed polylactic acid and validated both in a static human arm channel and in a dynamic setting, where the human subject performs various tasks. This antenna outperforms an off-the-shelf printed circuit board (PCB) antenna by 18 dB and a rectangular patch antenna by 4 dB in terms of link budget at a separation distance of 20 cm, both in line of sight and non-LOS path loss experiments. Additionally, while performing four commonplace activities, the average power received increased by 20 dB in an on-body link established between two of our novel antennas rather than two of the PCB antennas. These results will aid in the development of wireless prostheses used by a growing number of amputees
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
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