1,720,956 research outputs found
Introduction to the issue on progress in solid-state, fiber, and tunable sources
No full textThe 42 papers in this special issue are focused on progress in solid-state, fiber, and tunable sources. The issue is dedicated to the memory of Theodore H. Maiman, who kicked off the rapid growth of solid-state laser development in 1960. The papers are organized into six subject areas: power scaling strategies; fiber lasers and amplifiers; thin-disk lasers; planar waveguide and thin slab lasers; tunable sources and nonlinear frequency conversion; and progress in laser materials
Ultrabroad mid-infrared tunable Cr:ZnSe channel waveguide laser
Get PDFOperation of a Cr:ZnSe external-cavity waveguide laser is demonstrated with a CW tuning range of 700 nm from 2077 to 2777 nm (36THz), the widest tuning range demonstrated by a waveguide laser. Narrow linewidths as low as 53 pm FWHM (3 GHz) are achieved and a maximum output power of 120 mW is attained at 2446 nm with over 15 mW available across the entire tunable range. A theoretical model is presented allowing the effect of changes to the system to be quantified in terms of laser performance, this allows the limitations of the architecture to be assessed. Good agreement is seen between the model and the experimental values obtained
Gain-switched operation of ultrafast laser inscribed waveguides in Cr:ZnSe
No full textWe report the first demonstration of a gain-switched chromium-doped zinc selenide channel waveguide laser. The guided-wave structure was produced by ultrafast laser inscription and exhibited output pulse energies up to 12 µJ . The laser exhibited narrow spectral output with a linewidth less than 1 nm. The beam quality was measured to be M2 = 7 with a highly multimode output profile. The laser had a maximum slope efficiency of 9.8% and no deleterious thermal effects were observed up to an average pump power of 3.3 W
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Get PDFWe 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
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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