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Methoden zur Verifikation von modellierten Schneeausaperungsmustern - Schrägluftbilder, Satellitenbilder und räumlich hochaufgelöste LIDAR Daten
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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
Influence of crop and agricultural landscape on soil erosion by water in bioenergy crop production
Get PDFThe production of maize, currently the most important energy crop, often negatively impacts the environment when cultivated conventionally. When maize is grown on slopes or soils with low water infiltration capacity, the risk of soil and nutrient loss due to water erosion increases significantly. Water erosion and the associated eutrophication of water bodies present societal challenges. The projected increase in winter precipitation and extreme rainfall events due to climate change aggravate this problem further. Therefore, the current practice of maize cultivation has considerable potential for optimization in the future. Alternative strategies for biomass production and energy generation are urgently needed. These can involve changes in cultivation methods or the cultivation of less well-known new crops, with perennial crops being of particular interest. Perennial crops are particularly suitable for erosion reduction, nutrient conservation, and thus for water protection due to the lack of soil tillage and their deep and intensive rooting. The perennial crop Silphium perfoliatum (commonly known as "cup plant") is being discussed as a possible alternative to maize. In addition to its high yield potential, cup plant also serves as a food source for insects in the summer and, through its regrowth after harvest, acts as a catch crop. As part of two field experiments, the erosion reduction potential of maize cultivation using direct seeding and the cultivation of the perennial crop Cup plant was tested in comparison to conventional maize cultivation. Erosion processes from natural heavy rainfall events, as well as from heavy rainfall simulations, were quantified. A significant reduction in erosion processes was observed with the cultivation of cup plant compared to conventionally grown maize. The slope conditions provide an initial general overview of the potential erosion risks of a site based solely on the relief characteristics. Derived from this, large-scale aggregated overviews for visualizing focus areas, in this case, regions with or without relief-induced erosion risk, are also feasible. The relief characteristics can often be more easily and comprehensively derived from DEM on a larger scale than from large-scale modeling efforts. In the context of this study, a slope classification was conducted to establish initial foundations for potential decision-making aids for the cultivation of cup plant. During the evaluation of heavy rainfall simulations conducted in 2022 and 2023, input parameters for the erosion model EROSION-3D for the perennial cup plant were calculated. The input parameters derived from the heavy rainfall simulations were used to model the erosion reduction potential of alternative cultivation methods and crops using EROSION-3D for a test area. It was found that introducing the direct seeding method for maize could reduce soil erosion by about 50% during a rainfall event. In comparison, establishing cup plant would result in approximately 90% less soil erosion. The application of the EROSION-3D model aims to spatially and temporally capture erosion risks in a differentiated manner to provide important decision-making aids for various stakeholders (planning experts, environmental authorities, farmers). Well-parameterized soil erosion models are essential for innovative cropping systems and the anticipated small-scale field design due to agriculture’s digitization (robotics). Field-specific diversification within the field requires small-scale soil erosion modeling to capture soil redistribution processes within the fields. Due to their generalizing characteristics, physically-based erosion models like Erosion-3D are particularly significant and provide detailed results. In this context, a well-parameterized erosion model can quantify and assess the erosion reduction potentials of cup plant on field-specific risk areas (flow paths, depressions).Die Erzeugung von Mais als derzeit wichtigster Energiepflanze geht bei konventionellem Anbau vielfach mit negativen Wirkungen auf die Umwelt einher. Wird Mais in Hanglagen bzw. auf Böden mit geringer Wasserinfiltrationsleistung angebaut, steigt das Risiko von Boden- und Nährstoffverlusten durch Wassererosion deutlich an. Wassererosion und die damit verbundene Gewässereutrophierung stellen gesamtgesellschaftliche Herausforderungen dar. Die prognostizierten höheren Winterniederschläge sowie die durch den Klimawandel bedingte Zunahme von Niederschlagsextremen bewirken eine weitere Verschärfung dieses Problems. Die derzeitige Anbaupraxis von Mais bietet daher auch zukünftig erhebliches Optimierungspotenzial. Besonders für den Gewässerschutz eignen sich Dauerkulturen, da sie durch den Verzicht auf Bodenbearbeitung und ihre tiefe Durchwurzelung Bodenerosion reduzieren und Nährstoffe im Boden halten. Eine potenzielle Alternative zu Mais ist die Dauerkultur Durchwachsene Silphie (nachfolgend kurz „Silphie“) . Sie zeichnet sich nicht nur durch ein hohes Ertragspotenzial aus, sondern bietet im Sommer auch eine Nahrungsquelle für Insekten und fungiert nach der Ernte als Zwischenfrucht. Neben alternativen Kulturpflanzen ist auch die Verbesserung der Maisanbauverfahren auf Hängen entscheidend. Direktsaatverfahren könnten durch die ganzjährige Bodenbedeckung mit Pflanzen oder Mulchmaterial zur Verringerung von Nährstoffverlagerung und Bodenerosion beitragen. Im Rahmen von zwei Feldversuchen wurde das Erosionsminderungspotenzial von Maisanbau im Direktsaatverfahren und der Anbau der Dauerkultur Durchwachsene Silphie im Vergleich zum konventionellen Maisanbau getestet. Erosionsprozesse natürlicher Regen- und Starkregenereignisse sowie von Starkregensimulationen wurden quantifiziert. Eine deutliche Reduktion von Abtragsprozessen durch den Anbau der Durchwachsenen Silphie gegenüber konventionell angebautem Mais konnte beobachtet werden. Die Hangneigungsverhältnisse bieten einen ersten allgemeinen Überblick über mögliche Erosionsgefährdungen eines Standortes allein basierend auf den Reliefeigenschaften. Abgeleitet daraus sind auch großräumig aggregierte Übersichten zur Visualisierung von Schwerpunktgebieten, in diesem Fall von Regionen mit/ohne reliefbedingter Erosionsgefährdung realisierbar. Die Reliefeigenschaften sind aus Geländemodellen häufig einfacher und in größerem Maßstab flächendeckend abzuleiten, als großmaßstäbige Modellierungsarbeiten. Im Rahmen dieser Studie wurde eine Hangneigungsklassifizierung durchgeführt, um erste Grundlagen für potentielle Entscheidungshilfen zum Anbau der Silphie zu schaffen. Im Zuge der Auswertung von durchgeführten Starkregensimulationen der Jahre 2022 und 2023 konnten die Eingangsparameter für das Erosionsmodell EROSION-3D für die Dauerkultur Durchwachsene Silphie berechnet werden. Die durch die Starkregensimulationen berechneten Eingangsparameter wurden genutzt, um das Erosionsminderungspotenzial alternativer Anbaumethoden und –kulturen unter Anwendung von EROSION-3D für ein Testgebiet zu modellieren. Es zeigte sich, dass durch die Einführung des Direktsaatverfahrens für Mais eine Reduktion des Bodenabtrags bei einem Niederschlagsereignis um ca. 50 % zu erreichen wäre, während durch die Etablierung von Silphiebeständen ca. 90 % weniger Bodenabtrag stattfinden würde. Mit der Anwendung des Modells EROSION-3D wird das Ziel verfolgt, Erosionsrisiken räumlich und zeitlich differenziert zu erfassen, um wichtige Entscheidungshilfen für diverse Stakeholder (Fachplanung, Umweltverwaltung, Landwirte) bereitzustellen. Gut parametrisierte Bodenerosionsmodelle sind bezogen auf innovative Anbaustrukturen und die zu erwartende kleinräumige Feldgestaltung im Zuge der Digitalisierung (Robotik) der Landwirtschaft obligatorisch. Schlaginterne Felddiversifizierung bedarf kleinräumiger Erosionsmodellierungen, um schlaginterne Bodenumverteilungsprozesse zu erfassen. Aufgrund ihrer generalisierenden Eigenschaften sind physikalisch basierte Erosionsmodelle wie Erosion-3D dabei von besonderer Bedeutung und bieten detailreiche Ergebnisse. Auch in diesem Kontext kann ein gut parametrisiertes Erosionsmodell Erosionsminderungspotentiale der Silphie auf schlaginternen Risikogebieten (Abflussganglinien, Senken) quantifizieren und ausweisen
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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