1,720,987 research outputs found
Mechanisms of compression in well-graded saprolitic soils
Full text linkSoils originating from weathering processes present considerable heterogeneity in their composition, which can make it difficult to analyse their behaviour in a systematic way. For the granitic saprolites discussed in this paper, based on a trend between soil density and weathering degree, there appears to be two different domains of behaviour, a granular domain and a clay matrix one, according to the degree of weathering reached. Recognition of these domains can reduce the apparent scatter of data for the engineering behaviour of weathered soils. A number of one-dimensional compression tests are presented for saprolitic soils from Hong Kong having different weathering degrees. In addition, isotropic and one-dimensional compression tests from the literature on other saprolites from Hong Kong and around the world were reanalysed and used to identify possible trends in the mechanisms of compression for these two domains. From practical considerations, the trends considered were between compressibility and common engineering grading descriptors. An attempt was also made to provide the physical explanations behind the behaviour observed, and the particle breakage was investigated in detail, both from a quantitative and qualitative point of view. It was found that the values of relative breakage (Hardin in ASCE J Geotech Geoenviron Eng 111(10):1177–1192, 1985), for a same stress level, might be very similar for soils having different compressibility values and different initial gradings. When studying particle breakage in further detail, it can be observed that it is linked to the amount of large particles and their characteristics. The maximum particle size, rather than the amount of fines in a mixture, may be a better predictor for differences in compressibility and breakage
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
Recent developments in equipment and interpretation of cone penetration test for soil characterization
No full textOver the last decades cone penetration testing has become the most widely used in-situ testing technique for stratigraphic profiling and site characterization. As a consequence of such extensive use, which has also rapidly spread to many new areas of application, a considerable amount of research has been carried out in terms of equipment, testing procedures, analysis of the penetration mechanisms and methods for data interpretation. This paper aims at providing a general picture of the major trends in CPT research carried out over the recent years, by presenting the most significant emerging innovations in instrumentation and the latest advances in the analysis of tests on sediments other than “standard” clays and sands and thus referred to as “non-standard” or “unusual” geomaterials. Attention is especially focused on intermediate sediments, such as silts, sandy silts, clayey sands and other sedimentary soils having very scattered grain size distributions and therefore potentially affected by partial drainage effects during cone penetration tests. The body of knowledge on such effects, as accumulated worldwide from both laboratory and field research, is reviewed and discussed, with special emphasis on the experimental results obtained from variable rate piezocone tests carried out in a few intermediate soil deposits in northern Italy. It is shown that the efforts of many researchers have mainly focused on the identification of cone penetration velocities required to ensure fully drained or fully undrained testing conditions, with reference to different soil classes or macrofabrics. Indeed, the preliminary identification of drainage conditions is a key step in order to avoid misinterpretation of field measurements and thus to develop interpretation procedures that could lead to a rational selection of soil parameters and economical design
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
Novel procedure for measuring the saturation of the pore-pressure system in piezocone tips
Full text linkUncertainty in the measurement of the cone penetration test with pore-water pressure measurement (i.e. piezocone testing CPTU) can be caused by an equipment malfunction, poor calibration and maintenance of sensors, but also by a lack of saturation of the piezocone. The standards allow for many different options in terms of filters, saturation fluids and methodologies. The novel device described herein aims at measuring in a very simple manner the degree of saturation of the piezocone prior to testing. Because the quality of pore-water pressure measurements can currently only be assessed a posteriori - that is, after the test has been completed, or at best while testing, the methodology proposed herein has the potential to provide quality benchmarks for CPTU. The tool measures a parameter inspired by the well-established Skempton coefficient B, which is routinely used to estimate the sample saturation prior to laboratory testing. Furthermore, by performing the same measurement after a CPTU test, it is possible to assess whether saturation was lost during cone penetration. The paper describes a set of preliminary results that show a clear correlation between the saturation degree of filters and/or of the overall pore-pressure measurement system and the B parameter proposed, thus providing a proof of concept in laboratory settings
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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