1,721,109 research outputs found
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
Jahresvariation der chemischen Zusammensetzung und der Quellzuordnung von luftgetragenen Partikeln in Peking
No full textThis study is a systematic comprehensive investigation of PM exposure in Beijing. It provides a clear source apportionment of PM in all seasons, especially during haze episodes. The results show that secondary inorganic ion formation and biomass burning are the main sources for haze in summer and autumn, winter haze is dominated by a mixture of different sources especially by coal combustion, while spring haze is mainly caused by mineral dust. Backward trajectory analyses showed that the southerly industrial regions are the main sources of particles during haze in Beijing.Diese Arbeit ist eine systematische, umfassende Untersuchung der Partikelbelastung in Peking. Es wird eine vertiefte Kenntnis der Quellen von Partikeln in allen Jahreszeiten, vor allem während Dunstepisoden, erlangt. Die Quellzuordnung zeigte, dass sekundäre anorganische Ionenbildung und Biomasseverbrennung die Hauptquellen des Dunstes im Sommer und Herbst sind. Im Winter dominiert eine Vielzahl von Quellen, vor allem die Kohleverbrennung, und im Frühjahr ist die Hauptquelle Mineralstaub. Rückwärts-Trajektorien-Analysen zeigten, dass die südlichen Industriegebieten eine Hauptquelle der Partikel während Dunstepisoden in Peking sind
Einfluss von Bewirtschaftung und Renaturierung auf die Treibhausgasflüsse eines präalpinen Hochmoors
No full textI investigated the changes in greenhouse gas fluxes of a prealpine bog after restoration. Short- and long-term restoration was effective in GHG reduction and vegetation shift on former ditches. Long-term restoration on drier sites led to natural like vegetation and GHG balances. Rising water tables caused CH4 emissions, which were overcompensated by reduced CO2 releases and raised plant productivity. On a bog meadow, rewetting reduced the GHG emissions to the half up to neutral balances. Ending management and establishment of Sphagnum turned the sites into strong sinks for GHG.Die Renaturierung eines präalpinen Hochmoors führte rasch zur Reduktionen der Treibhausgasflüsse und einem Vegetationswechsel auf ehemaligen Gräben. Nach 15 Jahren waren auf allen Flächen naturnahe Vegetation und THG Bilanzen feststellbar. Auftretende CH4 Emissionen wurden durch verringerte CO2 Freisetzung und erhöhte Pflanzenproduktivität überkompensiert. Auf einer Hochmoorwiese senkte die Wiedervernässung die THG Emissionen um die Hälfte bis hin zur Neutralität. Das Nutzungsende und die Besiedlung mit Sphagnen machten die Flächen zu sicheren Senken für THGs
Flugzeuggetragene Beobachtungen von Ruß-Aerosolschichten in mittleren Breiten
No full textModel studies show that black carbon (BC) is, after CO2, the second strongest component of current global warming. In this study, microphysical and optical properties of BC-containing aerosol layers at mid-latitudes were investigated based on airborne in situ observations during the CONCERT 2011 field experiment. For the first time, the Single Particle Soot Photometer was operated onboard the research aircraft Falcon. Besides comprehensive results to BC in aerosol layers, this study shows the relevance of pyro-convective forest fires to the BC burden in the upper troposphere.Modellstudien zeigen, dass Ruß nach CO2 den zweitstärksten Beitrag zur globalen Erderwärmung aufweist. Basierend auf flugzeuggetragenen in-situ Beobachtungen und erstmals das Single Particle Soot Photometer auf dem Forschungsflugzeug Falcon verwendend, wurden in dieser Arbeit mikrophysikalische und optische Eigenschaften von rußenthaltenden Aerosolschichten in den mittleren Breiten untersucht. Neben umfassenden Informationen zu Ruß in Aerosolschichten verdeutlicht diese Arbeit unter anderem die Relevanz von pyro-konvektiven Waldbränden für die Rußbelastung in der oberen Troposphäre
Netto Ökosystemaustausch von CO<sub>2</sub> über einem naturbelassenen Windwurf in einem Fichtenbergwald des Nationalparks Bayerischer Wald
No full textNet ecosystem exchange of CO2 (NEE) was measured in a wind-throw-disturbed upland spruce forest in the Bavarian Forest National Park from 2009 to 2013, by the eddy covariance method. The results show that 1) low productive mountainous forest sites may switch from a carbon source to a carbon sink within relatively few years after disturbance, and 2) main uncertainties in process understanding originate from poorly resolved dynamics in soil respiration and succession of ground cover species development.Von 2009 bis 2013 wurde der Netto Ökosystemaustauch von CO2 über einem Windwurfgebiet im Bayerischen Wald mittels der Eddy Kovarianz Methode bestimmt. Die Ergebnisse zeigen, dass 1) sich Standorte an langsam wachsenden Bergwäldern innerhalb weniger Jahre nach einer Störung von einer Kohlenstoffquelle wieder in eine Senke umwandeln dürften und 2) die hauptsächlichen Unsicherheiten beim
Prozessverständnis in der Bodenrespiration und in der Entwicklung der Bodenvegetation begründet sind
Turbulenzstruktur im gestörten Nachlauf einer künstlichen Oberflächenmodifikation: ein Feldexperiment
No full text- …
