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Global Warming perspectives and new solutions- Editorial
No full textThe Editorial of The Special Issue of The International Journal of Global Warming, "Global Warming perspectives and new solutions
“Recent Advances in Energy Research”
Full text linkThe worldwide scarcity of fossil fuels regarding primary energy demand together with growing environmental concerns have raised new challenges to the world economy, and led to changes in the energy paradigm. Industry, services, researchers, and the Academy are challenged to envisage new solutions through setting up new conversion processes, designing new power systems, and investigating and developing new energy sources and vectors
and Development, from the Individual Researcher to research Empires
Full text linkThis paper is dated: it was written at the time of the celebration of the 20 years of activity of the Évora Geophysics Centre (CGE). It comprises a brief appraisal of the evolution of scientific research in Europe and in the United States of America, together with a special reference to the development of the Portuguese scientific system. The size distribution of scientific teams in the whole system is addressed, and it is shown that at a state of optimal performance there is room for all team sizes ranging from the individual investigator to research empires. Similarly, we note that research dynamics evolve in time with periods of strong creation intensity that alternate with periods of extension and quiescence. We also note that the new perspectives for the European Research Area, with policies that push strongly to the development side, may be risky in the long term as they might lessen creation, which is the base for sustainability and development. Finally, we briefly address the challenges ahead both for the Portuguese scientific system and the CGE
Special Issue “Sustainable Energy Sources and Developing Clean Energy Technologies”
Full text linkEnergy and sustainability are issues in the global agenda. The concern for the impacts
of energy use, which adds to the alarm for the scarcity of primary sources of energy, has triggered new research on sustainable primary energy sources and on c1ean and efficient energy systems and processes. Due to the current global warming, the link between energy and environment became inescapable in such a way that researchers have to deal both with efficiency and environmental impacts. In the last few years, forums worldwide have addressed these global issues from different perspectives.
This Special issue of the International Journal of Green Energy inc1udes selected
papers devoted mainly to sustainable energy sources and developing c1ean energy technologies.
The guest editors are grateful to the authors who contributed to this special issue and
to all colleagues that participated in the review process
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
Teorias de electrificação das nuvens
No full textEste trabalho tem como objetivo avaliar as várias teorias que têm vindo a ser propostas ao longo dos últimos anos, na
tentativa de encontrar uma explicação consensual e coerente para uma questão que permanece ainda hoje por
resolver: “Porque e Como se eletrificam as nuvens de tempestade.” É revisto todo o processo global que ocorre na
atmosfera, desde a molécula neutra à formação da tempestade, passando pela formação de iões (ionização) e
separação de cargas na atmosfera. Surge desde logo a questão de como se mantém carregado e quem são os
geradores de corrente de alimentação deste circuito. É analisada a primeira teoria proposta por Wilson, e as várias
que se seguiram por alguns autores, na tentativa de resolver as lacunas que a teria de Wilson não conseguia preencher.
A origem da densidade de corrente, constantemente presente na atmosfera, ficou conhecida como o problema
fundamental da eletricidade atmosférica. A primeira tentativa para resolver este problema foi sugerida por C. T. R.
Wilson em 1920 e desde então que este assunto tem sido alvo de muitos estudos por parte da comunidade científica,
entre os quais se destacam Harrison, Kasernir, Ogawa e Wilson, largamente citados neste trabalho. Em resumo
podemos atualmente constatar que a radiação cósmica, a ionização que ocorre na ionosfera (fotoionização) e as
tempestades constituem os três geradores principais no circuito elétrico global. É analisado também o modo como as
alterações climáticas podem perturbar este sistema elétrico pois os parâmetros elétricos atmosféricos podem ser bons
indicadores de modificações no clima elétrico planetário. As medições elétricas atmosféricas constituem assim uma
fonte promissora de informação ambiental. Por fim introduz‐se então a questão da eletrificação das nuvens
apresentando algumas teorias que, não respondendo totalmente à questão, pelo menos fornecem pequenos
contributos, que representam os passos em frente na sua clarificação. /ABSTRACT ‐ This work pretend evaluates
various theories that has been proposed along the last years, in attempt to found a consensual and coerent
explanation for one question that remains to resolve until now: “Why and how the thunderclouds become electrified.”
All the global process, that occur in atmosphere, is review, from the neutral molecule to the formation of the
tunderstorm, passing by ions formation (ionization) and charge separation in atmosphere. Soon arises the question
how remain charged and who are de generators of this circuit. It is analyzed the first theory proposed by Wilson, and
the others that were proposed later by many authors, trying to resolve the gaps that Wilson theory do not fill out.
The origin of current density, always present in atmosphere is known by Fundamental problem of atmospheric
electricity. The first attempt to resolve this problem was suggest by Wilson in 1920 and since then this subject has
been target of many studies by scientists, with distinction for Harrison, Kasemir, Ogawa and Wilson, largely cited in
this work. Briefly now we can stablish that cosmic radiation, ionization in ionosphere (fotoionization) and the
thunderstorms are the main three generators in global electric circuit. It is analyzed too the way how climate changes
might disturbed this electric system so the atmospheric electric parameters can be good indicators of changes in
planetary electric clime. Atmospheric electric measurements be a promising source of environmental information.
Finally we introduce the question about electrification of clouds presenting some theories that no give all the answers
but furnish littles contributes, representing some steps forward in the way of its clarification
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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