1,720,997 research outputs found
Prediction of Soil Properties with PLSR and vis-NIR Spectroscopy: Application to Mediterranean Soils from Southern Italy
No full textA geostatistical sensor data fusion approach for delineating homogeneous management zones in Precision Agriculture
No full textApplication of Precision Agriculture requires an accurate assessment of fine-resolution spatial variation. At present, advances in proximal sensing and spatial data analysis are available to characterize soil systems and detect changes in physical or chemical properties useful to understand and manage the variation within fields in a site-specific way. The objective of this work was to verify the suitability of geostatistical techniques to fuse data measured with different geophysical sensors for delineating homogeneous within-field zones for Precision Agriculture. A geophysical survey, using electromagnetic induction (EMI) and ground penetrating radar (GPR), was carried out at Montecorvino Rovella in the southern Apennines (Salerno, Italy). Both sensors (EMI and GPR) enabled the assessment of variation of soil dielectric properties both laterally and vertically. The study area is a 5 ha terraced olive grove under organic cropping. The sensor surveys were carried out along the terraces and over the entire field. The multi-sensor data were analyzed using geostatistical techniques to estimate synthetic scale-dependent regionalized factors. The results allowed the division of the study area into smaller areas, characterized by different properties that could impact agronomic management. In particular, a large area was delineated in the northern part of the grove, where apparent soil electrical conductivity and radar attenuation were greater. Through soil profiling it was shown that soils of the northern macro-area refer to deep, well developed, clayey Luvic Phaezem, whereas soils of the southern macro-area are shallower and less developed, sandy loam Leptic Calcisol. The proposed geostatistical approach effectively combined the complementary 2D EMI and 3D GPR measurements, to delineate areas characterized by different soil horizontal and vertical conditions. This within-olive grove partition might be advantageously used for site-specific tillage and fertilization
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
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
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
Frontier-Line Analysis
Full text linkMaximum carbon storage
The globe is warming, and scientists are now agreed that the cause is the increased concentration of CO2 in the atmosphere in the last 100 years or so. Much of that extra CO2 has come from our burning fossil fuels to heat our buildings and generate electricity. Manufacturing industry and transport have played their parts. So too has agriculture. The clearance of forests, land drainage and cultivation for
arable crops have led to the oxidation of carbon in the soil and the release of huge quantities of carbon as CO2. The International Panel on Climate Change (IPCC) reckons that the globe will soon be 1.5 degrees C warmer than before industrialization. Delegates at the recent meeting COP27 wished to limit that increase by 2050, but they failed to agree on cuts to emissions to achieve it. Worse, if emissions continue at the current rate then an increase to 2 degrees C is likely sometime this century. Such warming is predicted to
have dire consequences: a rise in sea level globally, submergence of island nations and coastal settlements,
increased flooding in some regions and drought in others, more wild fires etc. If we are to avoid such ills and prevent global warming's exceeding L5'c then we need to limit the net increase in CO2 in the atmosphere to zero. Scientists, stake-holders and politicians are therefore turning their attention to the capture and storage of gases and sequestration of carbon; their aim is 'net zero' emissions. The capture and storage of CO2 at source from factories and power stations are matters of technology.
Those from the atmosphere must depend on Nature -by photosynthesis, and on land by storage of carbon in the soil. The soil could store more carbon than it does by more judicious land use and sound management. In that way the soil would provide a more long-lasting store of carbon than that in the vegetation; and it would also improve the soil as a medium for plant growth and ecosystems services such as greater storage of water and reduced run-off, erosion and flooding. The question then is: could the soil store in the long term more c than it does at present while at the same time sustaining its productive use? We know from long-term field experiments that for any given form of land management the amount of carbon in the soil reaches an equilibrium in which gains balance losses, and some experiments seem to show that there is a maximum amount that the soil can store (West & Six, 2007). The soil gains carbon initially as organic residues or manure, largely as only partly decomposed particles. Those are mineralized rapidly by soil organisms, and approximately 90% of the carbon is lost within 30 years (Basile-Doelsch et al 2020). Much of the rest decomposes more slowly into smaller molecules that bind to mineral surfaces where they are protected
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