1,720,954 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
Experimental and analytical tools for rapid development of digital imaging-based elasto-tomography technology
Get PDFBreast cancer is the second most common cancer in the world and has the highest cancer mortality rate in women. Presently, 1 of every 4 women carry an increased risk of breast cancer, of which, 6% are below the minimum screening age of 45. Early detection via regular screening not only reduces mortality rates, but also decreases overall treatment expenditure. X-ray mammography is the clinical standard breast cancer screening technique. However, due to significant limitations, such as unacceptable rates of false positive and false negative results, exposure to ionizing radiation, and discomfort and pain due to the compression of the breast it is not recommended for women under 45 years of age. These women also often have denser breast tissues, which further reduce mammography efficacy and diagnostic capability.
Digital imaged elasto-tomography (DIET) has been developed to overcome some of the limitations of current techniques and mammography in particular. The digital imaged elasto-tomography (DIET) concept is based on non-invasive, pain-free, vibration based analysis of local tissue stiffness, a form of elastographic reconstruction from actuation motion. This technique enables early detection of breast cancer, as it is not restricted in the ages of women who could utilize it for screening. Thus, combined with effective treatment, it could reduce mortality, particularly for younger women. More specifically, recent analysis showing annual mammography down to 40 years of age would save many more lives than current screening, indicating a system like DIET, safely offering screening to any age, could significantly improve breast cancer mortality. DIET is a novel method and technology, but is not yet at a stage suitable for a large randomised clinical trial. However, its development could be significantly enhanced by a series of tools to improve the speed and repeatability of DIET technology development. Currently, DIET is developed primary by executing pilot clinical testing of human volunteers. This experimental approach is slow, not repeatable as technology progresses and thus not necessarily optima, as well as placing a burden on diagnosed volunteer patients. In particular, repeating trials is not possible, limiting the ability to accurately assess technological changes.
The productivity of DIET technology development could thus be enhanced in three main areas: a) development of realistic and accurate tissue mimicking breast phantoms; b) validation of the surface measurement algorithms to quantify their error and thus to quantify the limits of diagnostic algorithms; and c) development of finite element models to accurately mimic breast phantoms to avoid repeated phantom experiments. The first would allow repeatable phantom trials in lieu of relying on volunteers. The second would enable more accurate assessment of errors and their impact on surface motion diagnostics. Equally, it would also allow assessment of whether improvements in sensing or actuation would make a clinical differences. The final, third element would further improve productivity by replacing phantom tests with models to generate “data”. The overall outcome is significantly enhanced development pathways.
In this thesis, mechanical properties of three different materials; agar, gelatine, and silicone used to emulate the mechanical behavior of real breast tissue are measured to assess their suitability for use in phantoms in systems assessing tissue mechanics for diagnostics. The stiffness ratio of adipose to tumor between the phantom materials and real human tissues were compared. Hyperelastic parameters of Neo-Hookean, Mooney Rivil, and Ogden models were obtained for the selected silicone material due to its appropriate mechanical properties, reliability, and repeatability. Finally, silicone based three homogenous phantoms of selected material were fabricated with different sizes of tumor.
Finite element models of breast shaped phantoms were developed using ABAQUS software. The geometry of the model was constructed with the same dimensions from fabricated phantoms. The mechanical properties were modeled by using the Neo-Hookean hyperelastic material model. Results showed good to strong correlation ranging from 0.7 to 1.0 in all cases with over 90% having a value over 0.9.Overall, the comparison of the DIET experimental data and the FE model data showed good agreement.
A single point laser Doppler vibrometer was used to validate the optical flow motion measuring algorithm used in DIET experimental data. Results show excellent validation with errors less than 6 % for healthy phantom, and errors less than 8 % for 10 mm and 20 mm inclusions. Overall results show the optical flow algorithm is validated with relatively small errors compared to a gold-standard, non-contact laser measurement.
Finally, because of the validation effectiveness and accuracy of finite element modeling compared to DIET experimental data. Six new phantoms were modeled with different tumor positions. This analysis assess the impact of tumor position on diagnosis of breast cancer using surface motions and basic elastography assumptions, which should further impact and encourage the development of DIET.
Overall, all 3 goals are accomplished. The results of this thesis provide means to dramatically speed up development of the DIET system. More generally, they provide significant results to enable elastographic technology development
Large deforamation of thin-walled tubular structure
Get PDFIn automobile and aerospace industries, thin-walled tubular structures have been widely used as key components to improve energy absorption capacity under axial compressive loads, which play an important role in improving the vehicle crashworthiness without increasing body weight. In this project, low carbon steel has been used to study the effect of loading rate onto sheet metal. Metallurgical study carried out to identify microstructure, chemical composition and hardness test of low carbon steel. From tension test at 0.001/s strain rate, stress-strain curve develop to identify the mechanical properties. Johnson –Cook model technique is adopted and parameters of Johnson – Cook model (A, B, C, m and n) have been extracted and use in FE simulation. Strain gauge rosette inserted on the center of the tube to determine strain at specific points on the structure. Wood of 10mm inserted at the top and bottom of the tube to avoid localized buckling. Then, axial compression test has been conducted experimental and FE simulation to validate the results
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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