1,721,326 research outputs found
Wealth reallocation and sustainability under climate change
No full textClimate change is often described as the greatest environmental challenge of our time. In addition, a changing climate can reallocate natural capital, change the value of all forms of capital and lead to mass redistribution of wealth. Here we explain how the inclusive wealth framework provides a means to measure shifts in the amounts and distribution of wealth induced by climate change. Biophysical effects on prices, pre-existing institutions and socio-ecological changes related to shifts in climate cause wealth to change in ways not correlated with biophysical changes. This implies that sustainable development in the face of climate change requires a coherent approach that integrates biophysical and social measurement. Inclusive wealth provides a measure that indicates sustainability and has the added benefit of providing an organizational framework for integrating the multiple disciplines studying global change.Peer reviewe
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
High power, diode pumped, single frequency lasers
No full textThis thesis presents experimental and theoretical work on the development of high power (i.e. multi-Watt) single frequency lasers, with the main emphasis on using intra-cavity second harmonic generation to produce high power visible output. With such a laser, pumped by a beam shaped 20W diode bar, we have obtained over 3W of TEM00 single frequency output at 532nm. Because of the strong non-linear effects introduced into the resonator cavity by the frequency doubler, the behaviour of the laser can be significantly altered. In particular, there is the previously unreported phenomenon of mode-hopping suppression, where the non lasing modes are suppressed by the nonlinear loss (due to sum-frequency generation with the lasing mode). This allows the lasing mode to be smoothly tuned over many mode spacings simply by scanning the cavity length. Tuning ranges of up to 80GHz have been measured, and are in good agreement with theoretical calculations. There are also some less desirable consequences of the high nonlinear loss, such as parasitic lasing, self misalignment, and bidirectional lasing, that have had to be overcome in order to achieve efficient operation.Ring lasers can provide, arguably, the most robust and stable single frequency operation. However care must be taken in their design to minimise spatial hole burning. Even a small amount of residual spatial hole burning can cause multi-frequency operation in ring lasers. This thesis contains experimental measurements of spatial hole burning and compares these with a numerically calculated theory. Also, the technique of pump beam displacement to increase the single frequency performance of end-pumped ring lasers, suffering from residual spatial hole burning, is described.Thermal effects, such as thermal lensing and thermally induced birefringence often prove to be a major limiting factor in efficient operation of high power lasers. However these effects are dependent on several factors, such as the resonator design, and the heat sinking of the laser rod. Described in this thesis are the steps we have taken to minimize these effects in the designs of the high power lasers we have constructed
Magnetization switching and spin-dependent transport in REFe2 exchange spring multilayers
No full textEThOS - Electronic Theses Online ServiceGBUnited Kingdo
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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